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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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
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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.c"
234 /*-------------------------------------------------------------------------*/
239 /* FSF callback functions */
240 struct fsg_operations {
242 * Callback function to call when thread exits. If no
243 * callback is set or it returns value lower then zero MSF
244 * will force eject all LUNs it operates on (including those
245 * marked as non-removable or with prevent_medium_removal flag
248 int (*thread_exits)(struct fsg_common *common);
251 * Called prior to ejection. Negative return means error,
252 * zero means to continue with ejection, positive means not to
255 int (*pre_eject)(struct fsg_common *common,
256 struct fsg_lun *lun, int num);
258 * Called after ejection. Negative return means error, zero
259 * or positive is just a success.
261 int (*post_eject)(struct fsg_common *common,
262 struct fsg_lun *lun, int num);
265 /* Data shared by all the FSG instances. */
267 struct usb_gadget *gadget;
268 struct usb_composite_dev *cdev;
269 struct fsg_dev *fsg, *new_fsg;
270 wait_queue_head_t fsg_wait;
272 /* filesem protects: backing files in use */
273 struct rw_semaphore filesem;
275 /* lock protects: state, all the req_busy's */
278 struct usb_ep *ep0; /* Copy of gadget->ep0 */
279 struct usb_request *ep0req; /* Copy of cdev->req */
280 unsigned int ep0_req_tag;
282 struct fsg_buffhd *next_buffhd_to_fill;
283 struct fsg_buffhd *next_buffhd_to_drain;
284 struct fsg_buffhd *buffhds;
287 u8 cmnd[MAX_COMMAND_SIZE];
291 struct fsg_lun *luns;
292 struct fsg_lun *curlun;
294 unsigned int bulk_out_maxpacket;
295 enum fsg_state state; /* For exception handling */
296 unsigned int exception_req_tag;
298 enum data_direction data_dir;
300 u32 data_size_from_cmnd;
305 unsigned int can_stall:1;
306 unsigned int free_storage_on_release:1;
307 unsigned int phase_error:1;
308 unsigned int short_packet_received:1;
309 unsigned int bad_lun_okay:1;
310 unsigned int running:1;
312 int thread_wakeup_needed;
313 struct completion thread_notifier;
314 struct task_struct *thread_task;
316 /* Callback functions. */
317 const struct fsg_operations *ops;
318 /* Gadget's private data. */
322 * Vendor (8 chars), product (16 chars), release (4
323 * hexadecimal digits) and NUL byte
325 char inquiry_string[8 + 16 + 4 + 1];
332 struct fsg_lun_config {
333 const char *filename;
338 } luns[FSG_MAX_LUNS];
340 /* Callback functions. */
341 const struct fsg_operations *ops;
342 /* Gadget's private data. */
345 const char *vendor_name; /* 8 characters or less */
346 const char *product_name; /* 16 characters or less */
352 struct usb_function function;
353 struct usb_gadget *gadget; /* Copy of cdev->gadget */
354 struct fsg_common *common;
356 u16 interface_number;
358 unsigned int bulk_in_enabled:1;
359 unsigned int bulk_out_enabled:1;
361 unsigned long atomic_bitflags;
362 #define IGNORE_BULK_OUT 0
364 struct usb_ep *bulk_in;
365 struct usb_ep *bulk_out;
368 static inline int __fsg_is_set(struct fsg_common *common,
369 const char *func, unsigned line)
373 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
378 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
380 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
382 return container_of(f, struct fsg_dev, function);
385 typedef void (*fsg_routine_t)(struct fsg_dev *);
387 static int exception_in_progress(struct fsg_common *common)
389 return common->state > FSG_STATE_IDLE;
392 /* Make bulk-out requests be divisible by the maxpacket size */
393 static void set_bulk_out_req_length(struct fsg_common *common,
394 struct fsg_buffhd *bh, unsigned int length)
398 bh->bulk_out_intended_length = length;
399 rem = length % common->bulk_out_maxpacket;
401 length += common->bulk_out_maxpacket - rem;
402 bh->outreq->length = length;
406 /*-------------------------------------------------------------------------*/
408 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
412 if (ep == fsg->bulk_in)
414 else if (ep == fsg->bulk_out)
418 DBG(fsg, "%s set halt\n", name);
419 return usb_ep_set_halt(ep);
423 /*-------------------------------------------------------------------------*/
425 /* These routines may be called in process context or in_irq */
427 /* Caller must hold fsg->lock */
428 static void wakeup_thread(struct fsg_common *common)
430 /* Tell the main thread that something has happened */
431 common->thread_wakeup_needed = 1;
432 if (common->thread_task)
433 wake_up_process(common->thread_task);
436 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
441 * Do nothing if a higher-priority exception is already in progress.
442 * If a lower-or-equal priority exception is in progress, preempt it
443 * and notify the main thread by sending it a signal.
445 spin_lock_irqsave(&common->lock, flags);
446 if (common->state <= new_state) {
447 common->exception_req_tag = common->ep0_req_tag;
448 common->state = new_state;
449 if (common->thread_task)
450 send_sig_info(SIGUSR1, SEND_SIG_FORCED,
451 common->thread_task);
453 spin_unlock_irqrestore(&common->lock, flags);
457 /*-------------------------------------------------------------------------*/
459 static int ep0_queue(struct fsg_common *common)
463 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
464 common->ep0->driver_data = common;
465 if (rc != 0 && rc != -ESHUTDOWN) {
466 /* We can't do much more than wait for a reset */
467 WARNING(common, "error in submission: %s --> %d\n",
468 common->ep0->name, rc);
474 /*-------------------------------------------------------------------------*/
476 /* Completion handlers. These always run in_irq. */
478 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
480 struct fsg_common *common = ep->driver_data;
481 struct fsg_buffhd *bh = req->context;
483 if (req->status || req->actual != req->length)
484 DBG(common, "%s --> %d, %u/%u\n", __func__,
485 req->status, req->actual, req->length);
486 if (req->status == -ECONNRESET) /* Request was cancelled */
487 usb_ep_fifo_flush(ep);
489 /* Hold the lock while we update the request and buffer states */
491 spin_lock(&common->lock);
493 bh->state = BUF_STATE_EMPTY;
494 wakeup_thread(common);
495 spin_unlock(&common->lock);
498 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
500 struct fsg_common *common = ep->driver_data;
501 struct fsg_buffhd *bh = req->context;
503 dump_msg(common, "bulk-out", req->buf, req->actual);
504 if (req->status || req->actual != bh->bulk_out_intended_length)
505 DBG(common, "%s --> %d, %u/%u\n", __func__,
506 req->status, req->actual, bh->bulk_out_intended_length);
507 if (req->status == -ECONNRESET) /* Request was cancelled */
508 usb_ep_fifo_flush(ep);
510 /* Hold the lock while we update the request and buffer states */
512 spin_lock(&common->lock);
514 bh->state = BUF_STATE_FULL;
515 wakeup_thread(common);
516 spin_unlock(&common->lock);
519 static int fsg_setup(struct usb_function *f,
520 const struct usb_ctrlrequest *ctrl)
522 struct fsg_dev *fsg = fsg_from_func(f);
523 struct usb_request *req = fsg->common->ep0req;
524 u16 w_index = le16_to_cpu(ctrl->wIndex);
525 u16 w_value = le16_to_cpu(ctrl->wValue);
526 u16 w_length = le16_to_cpu(ctrl->wLength);
528 if (!fsg_is_set(fsg->common))
531 ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
534 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
536 switch (ctrl->bRequest) {
538 case US_BULK_RESET_REQUEST:
539 if (ctrl->bRequestType !=
540 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
542 if (w_index != fsg->interface_number || w_value != 0 ||
547 * Raise an exception to stop the current operation
548 * and reinitialize our state.
550 DBG(fsg, "bulk reset request\n");
551 raise_exception(fsg->common, FSG_STATE_RESET);
552 return DELAYED_STATUS;
554 case US_BULK_GET_MAX_LUN:
555 if (ctrl->bRequestType !=
556 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
558 if (w_index != fsg->interface_number || w_value != 0 ||
561 VDBG(fsg, "get max LUN\n");
562 *(u8 *)req->buf = fsg->common->nluns - 1;
564 /* Respond with data/status */
565 req->length = min((u16)1, w_length);
566 return ep0_queue(fsg->common);
570 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
571 ctrl->bRequestType, ctrl->bRequest,
572 le16_to_cpu(ctrl->wValue), w_index, w_length);
577 /*-------------------------------------------------------------------------*/
579 /* All the following routines run in process context */
581 /* Use this for bulk or interrupt transfers, not ep0 */
582 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
583 struct usb_request *req, int *pbusy,
584 enum fsg_buffer_state *state)
588 if (ep == fsg->bulk_in)
589 dump_msg(fsg, "bulk-in", req->buf, req->length);
591 spin_lock_irq(&fsg->common->lock);
593 *state = BUF_STATE_BUSY;
594 spin_unlock_irq(&fsg->common->lock);
595 rc = usb_ep_queue(ep, req, GFP_KERNEL);
598 *state = BUF_STATE_EMPTY;
600 /* We can't do much more than wait for a reset */
603 * Note: currently the net2280 driver fails zero-length
604 * submissions if DMA is enabled.
606 if (rc != -ESHUTDOWN &&
607 !(rc == -EOPNOTSUPP && req->length == 0))
608 WARNING(fsg, "error in submission: %s --> %d\n",
613 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
615 if (!fsg_is_set(common))
617 start_transfer(common->fsg, common->fsg->bulk_in,
618 bh->inreq, &bh->inreq_busy, &bh->state);
622 static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
624 if (!fsg_is_set(common))
626 start_transfer(common->fsg, common->fsg->bulk_out,
627 bh->outreq, &bh->outreq_busy, &bh->state);
631 static int sleep_thread(struct fsg_common *common)
635 /* Wait until a signal arrives or we are woken up */
638 set_current_state(TASK_INTERRUPTIBLE);
639 if (signal_pending(current)) {
643 if (common->thread_wakeup_needed)
647 __set_current_state(TASK_RUNNING);
648 common->thread_wakeup_needed = 0;
653 /*-------------------------------------------------------------------------*/
655 static int do_read(struct fsg_common *common)
657 struct fsg_lun *curlun = common->curlun;
659 struct fsg_buffhd *bh;
662 loff_t file_offset, file_offset_tmp;
667 * Get the starting Logical Block Address and check that it's
670 if (common->cmnd[0] == READ_6)
671 lba = get_unaligned_be24(&common->cmnd[1]);
673 lba = get_unaligned_be32(&common->cmnd[2]);
676 * We allow DPO (Disable Page Out = don't save data in the
677 * cache) and FUA (Force Unit Access = don't read from the
678 * cache), but we don't implement them.
680 if ((common->cmnd[1] & ~0x18) != 0) {
681 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
685 if (lba >= curlun->num_sectors) {
686 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
689 file_offset = ((loff_t) lba) << curlun->blkbits;
691 /* Carry out the file reads */
692 amount_left = common->data_size_from_cmnd;
693 if (unlikely(amount_left == 0))
694 return -EIO; /* No default reply */
698 * Figure out how much we need to read:
699 * Try to read the remaining amount.
700 * But don't read more than the buffer size.
701 * And don't try to read past the end of the file.
703 amount = min(amount_left, FSG_BUFLEN);
704 amount = min((loff_t)amount,
705 curlun->file_length - file_offset);
707 /* Wait for the next buffer to become available */
708 bh = common->next_buffhd_to_fill;
709 while (bh->state != BUF_STATE_EMPTY) {
710 rc = sleep_thread(common);
716 * If we were asked to read past the end of file,
717 * end with an empty buffer.
721 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
722 curlun->sense_data_info =
723 file_offset >> curlun->blkbits;
724 curlun->info_valid = 1;
725 bh->inreq->length = 0;
726 bh->state = BUF_STATE_FULL;
730 /* Perform the read */
731 file_offset_tmp = file_offset;
732 nread = vfs_read(curlun->filp,
733 (char __user *)bh->buf,
734 amount, &file_offset_tmp);
735 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
736 (unsigned long long)file_offset, (int)nread);
737 if (signal_pending(current))
741 LDBG(curlun, "error in file read: %d\n", (int)nread);
743 } else if (nread < amount) {
744 LDBG(curlun, "partial file read: %d/%u\n",
746 nread = round_down(nread, curlun->blksize);
748 file_offset += nread;
749 amount_left -= nread;
750 common->residue -= nread;
753 * Except at the end of the transfer, nread will be
754 * equal to the buffer size, which is divisible by the
755 * bulk-in maxpacket size.
757 bh->inreq->length = nread;
758 bh->state = BUF_STATE_FULL;
760 /* If an error occurred, report it and its position */
761 if (nread < amount) {
762 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
763 curlun->sense_data_info =
764 file_offset >> curlun->blkbits;
765 curlun->info_valid = 1;
769 if (amount_left == 0)
770 break; /* No more left to read */
772 /* Send this buffer and go read some more */
774 if (!start_in_transfer(common, bh))
775 /* Don't know what to do if common->fsg is NULL */
777 common->next_buffhd_to_fill = bh->next;
780 return -EIO; /* No default reply */
784 /*-------------------------------------------------------------------------*/
786 static int do_write(struct fsg_common *common)
788 struct fsg_lun *curlun = common->curlun;
790 struct fsg_buffhd *bh;
792 u32 amount_left_to_req, amount_left_to_write;
793 loff_t usb_offset, file_offset, file_offset_tmp;
799 curlun->sense_data = SS_WRITE_PROTECTED;
802 spin_lock(&curlun->filp->f_lock);
803 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
804 spin_unlock(&curlun->filp->f_lock);
807 * Get the starting Logical Block Address and check that it's
810 if (common->cmnd[0] == WRITE_6)
811 lba = get_unaligned_be24(&common->cmnd[1]);
813 lba = get_unaligned_be32(&common->cmnd[2]);
816 * We allow DPO (Disable Page Out = don't save data in the
817 * cache) and FUA (Force Unit Access = write directly to the
818 * medium). We don't implement DPO; we implement FUA by
819 * performing synchronous output.
821 if (common->cmnd[1] & ~0x18) {
822 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
825 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
826 spin_lock(&curlun->filp->f_lock);
827 curlun->filp->f_flags |= O_SYNC;
828 spin_unlock(&curlun->filp->f_lock);
831 if (lba >= curlun->num_sectors) {
832 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
836 /* Carry out the file writes */
838 file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
839 amount_left_to_req = common->data_size_from_cmnd;
840 amount_left_to_write = common->data_size_from_cmnd;
842 while (amount_left_to_write > 0) {
844 /* Queue a request for more data from the host */
845 bh = common->next_buffhd_to_fill;
846 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
849 * Figure out how much we want to get:
850 * Try to get the remaining amount,
851 * but not more than the buffer size.
853 amount = min(amount_left_to_req, FSG_BUFLEN);
855 /* Beyond the end of the backing file? */
856 if (usb_offset >= curlun->file_length) {
859 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
860 curlun->sense_data_info =
861 usb_offset >> curlun->blkbits;
862 curlun->info_valid = 1;
866 /* Get the next buffer */
867 usb_offset += amount;
868 common->usb_amount_left -= amount;
869 amount_left_to_req -= amount;
870 if (amount_left_to_req == 0)
874 * Except at the end of the transfer, amount will be
875 * equal to the buffer size, which is divisible by
876 * the bulk-out maxpacket size.
878 set_bulk_out_req_length(common, bh, amount);
879 if (!start_out_transfer(common, bh))
880 /* Dunno what to do if common->fsg is NULL */
882 common->next_buffhd_to_fill = bh->next;
886 /* Write the received data to the backing file */
887 bh = common->next_buffhd_to_drain;
888 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
889 break; /* We stopped early */
890 if (bh->state == BUF_STATE_FULL) {
892 common->next_buffhd_to_drain = bh->next;
893 bh->state = BUF_STATE_EMPTY;
895 /* Did something go wrong with the transfer? */
896 if (bh->outreq->status != 0) {
897 curlun->sense_data = SS_COMMUNICATION_FAILURE;
898 curlun->sense_data_info =
899 file_offset >> curlun->blkbits;
900 curlun->info_valid = 1;
904 amount = bh->outreq->actual;
905 if (curlun->file_length - file_offset < amount) {
907 "write %u @ %llu beyond end %llu\n",
908 amount, (unsigned long long)file_offset,
909 (unsigned long long)curlun->file_length);
910 amount = curlun->file_length - file_offset;
913 /* Don't accept excess data. The spec doesn't say
914 * what to do in this case. We'll ignore the error.
916 amount = min(amount, bh->bulk_out_intended_length);
918 /* Don't write a partial block */
919 amount = round_down(amount, curlun->blksize);
923 /* Perform the write */
924 file_offset_tmp = file_offset;
925 nwritten = vfs_write(curlun->filp,
926 (char __user *)bh->buf,
927 amount, &file_offset_tmp);
928 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
929 (unsigned long long)file_offset, (int)nwritten);
930 if (signal_pending(current))
931 return -EINTR; /* Interrupted! */
934 LDBG(curlun, "error in file write: %d\n",
937 } else if (nwritten < amount) {
938 LDBG(curlun, "partial file write: %d/%u\n",
939 (int)nwritten, amount);
940 nwritten = round_down(nwritten, curlun->blksize);
942 file_offset += nwritten;
943 amount_left_to_write -= nwritten;
944 common->residue -= nwritten;
946 /* If an error occurred, report it and its position */
947 if (nwritten < amount) {
948 curlun->sense_data = SS_WRITE_ERROR;
949 curlun->sense_data_info =
950 file_offset >> curlun->blkbits;
951 curlun->info_valid = 1;
956 /* Did the host decide to stop early? */
957 if (bh->outreq->actual < bh->bulk_out_intended_length) {
958 common->short_packet_received = 1;
964 /* Wait for something to happen */
965 rc = sleep_thread(common);
970 return -EIO; /* No default reply */
974 /*-------------------------------------------------------------------------*/
976 static int do_synchronize_cache(struct fsg_common *common)
978 struct fsg_lun *curlun = common->curlun;
981 /* We ignore the requested LBA and write out all file's
982 * dirty data buffers. */
983 rc = fsg_lun_fsync_sub(curlun);
985 curlun->sense_data = SS_WRITE_ERROR;
990 /*-------------------------------------------------------------------------*/
992 static void invalidate_sub(struct fsg_lun *curlun)
994 struct file *filp = curlun->filp;
995 struct inode *inode = file_inode(filp);
998 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
999 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
1002 static int do_verify(struct fsg_common *common)
1004 struct fsg_lun *curlun = common->curlun;
1006 u32 verification_length;
1007 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1008 loff_t file_offset, file_offset_tmp;
1010 unsigned int amount;
1014 * Get the starting Logical Block Address and check that it's
1017 lba = get_unaligned_be32(&common->cmnd[2]);
1018 if (lba >= curlun->num_sectors) {
1019 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1024 * We allow DPO (Disable Page Out = don't save data in the
1025 * cache) but we don't implement it.
1027 if (common->cmnd[1] & ~0x10) {
1028 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1032 verification_length = get_unaligned_be16(&common->cmnd[7]);
1033 if (unlikely(verification_length == 0))
1034 return -EIO; /* No default reply */
1036 /* Prepare to carry out the file verify */
1037 amount_left = verification_length << curlun->blkbits;
1038 file_offset = ((loff_t) lba) << curlun->blkbits;
1040 /* Write out all the dirty buffers before invalidating them */
1041 fsg_lun_fsync_sub(curlun);
1042 if (signal_pending(current))
1045 invalidate_sub(curlun);
1046 if (signal_pending(current))
1049 /* Just try to read the requested blocks */
1050 while (amount_left > 0) {
1052 * Figure out how much we need to read:
1053 * Try to read the remaining amount, but not more than
1055 * And don't try to read past the end of the file.
1057 amount = min(amount_left, FSG_BUFLEN);
1058 amount = min((loff_t)amount,
1059 curlun->file_length - file_offset);
1061 curlun->sense_data =
1062 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1063 curlun->sense_data_info =
1064 file_offset >> curlun->blkbits;
1065 curlun->info_valid = 1;
1069 /* Perform the read */
1070 file_offset_tmp = file_offset;
1071 nread = vfs_read(curlun->filp,
1072 (char __user *) bh->buf,
1073 amount, &file_offset_tmp);
1074 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1075 (unsigned long long) file_offset,
1077 if (signal_pending(current))
1081 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1083 } else if (nread < amount) {
1084 LDBG(curlun, "partial file verify: %d/%u\n",
1085 (int)nread, amount);
1086 nread = round_down(nread, curlun->blksize);
1089 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1090 curlun->sense_data_info =
1091 file_offset >> curlun->blkbits;
1092 curlun->info_valid = 1;
1095 file_offset += nread;
1096 amount_left -= nread;
1102 /*-------------------------------------------------------------------------*/
1104 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1106 struct fsg_lun *curlun = common->curlun;
1107 u8 *buf = (u8 *) bh->buf;
1109 if (!curlun) { /* Unsupported LUNs are okay */
1110 common->bad_lun_okay = 1;
1112 buf[0] = 0x7f; /* Unsupported, no device-type */
1113 buf[4] = 31; /* Additional length */
1117 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1118 buf[1] = curlun->removable ? 0x80 : 0;
1119 buf[2] = 2; /* ANSI SCSI level 2 */
1120 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1121 buf[4] = 31; /* Additional length */
1122 buf[5] = 0; /* No special options */
1125 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1129 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1131 struct fsg_lun *curlun = common->curlun;
1132 u8 *buf = (u8 *) bh->buf;
1137 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1139 * If a REQUEST SENSE command is received from an initiator
1140 * with a pending unit attention condition (before the target
1141 * generates the contingent allegiance condition), then the
1142 * target shall either:
1143 * a) report any pending sense data and preserve the unit
1144 * attention condition on the logical unit, or,
1145 * b) report the unit attention condition, may discard any
1146 * pending sense data, and clear the unit attention
1147 * condition on the logical unit for that initiator.
1149 * FSG normally uses option a); enable this code to use option b).
1152 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1153 curlun->sense_data = curlun->unit_attention_data;
1154 curlun->unit_attention_data = SS_NO_SENSE;
1158 if (!curlun) { /* Unsupported LUNs are okay */
1159 common->bad_lun_okay = 1;
1160 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1164 sd = curlun->sense_data;
1165 sdinfo = curlun->sense_data_info;
1166 valid = curlun->info_valid << 7;
1167 curlun->sense_data = SS_NO_SENSE;
1168 curlun->sense_data_info = 0;
1169 curlun->info_valid = 0;
1173 buf[0] = valid | 0x70; /* Valid, current error */
1175 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1176 buf[7] = 18 - 8; /* Additional sense length */
1182 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1184 struct fsg_lun *curlun = common->curlun;
1185 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1186 int pmi = common->cmnd[8];
1187 u8 *buf = (u8 *)bh->buf;
1189 /* Check the PMI and LBA fields */
1190 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1191 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1195 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1196 /* Max logical block */
1197 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1201 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1203 struct fsg_lun *curlun = common->curlun;
1204 int msf = common->cmnd[1] & 0x02;
1205 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1206 u8 *buf = (u8 *)bh->buf;
1208 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1209 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1212 if (lba >= curlun->num_sectors) {
1213 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1218 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1219 store_cdrom_address(&buf[4], msf, lba);
1223 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1225 struct fsg_lun *curlun = common->curlun;
1226 int msf = common->cmnd[1] & 0x02;
1227 int start_track = common->cmnd[6];
1228 u8 *buf = (u8 *)bh->buf;
1230 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1232 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1237 buf[1] = (20-2); /* TOC data length */
1238 buf[2] = 1; /* First track number */
1239 buf[3] = 1; /* Last track number */
1240 buf[5] = 0x16; /* Data track, copying allowed */
1241 buf[6] = 0x01; /* Only track is number 1 */
1242 store_cdrom_address(&buf[8], msf, 0);
1244 buf[13] = 0x16; /* Lead-out track is data */
1245 buf[14] = 0xAA; /* Lead-out track number */
1246 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1250 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1252 struct fsg_lun *curlun = common->curlun;
1253 int mscmnd = common->cmnd[0];
1254 u8 *buf = (u8 *) bh->buf;
1257 int changeable_values, all_pages;
1261 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1262 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1265 pc = common->cmnd[2] >> 6;
1266 page_code = common->cmnd[2] & 0x3f;
1268 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1271 changeable_values = (pc == 1);
1272 all_pages = (page_code == 0x3f);
1275 * Write the mode parameter header. Fixed values are: default
1276 * medium type, no cache control (DPOFUA), and no block descriptors.
1277 * The only variable value is the WriteProtect bit. We will fill in
1278 * the mode data length later.
1281 if (mscmnd == MODE_SENSE) {
1282 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1285 } else { /* MODE_SENSE_10 */
1286 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1288 limit = 65535; /* Should really be FSG_BUFLEN */
1291 /* No block descriptors */
1294 * The mode pages, in numerical order. The only page we support
1295 * is the Caching page.
1297 if (page_code == 0x08 || all_pages) {
1299 buf[0] = 0x08; /* Page code */
1300 buf[1] = 10; /* Page length */
1301 memset(buf+2, 0, 10); /* None of the fields are changeable */
1303 if (!changeable_values) {
1304 buf[2] = 0x04; /* Write cache enable, */
1305 /* Read cache not disabled */
1306 /* No cache retention priorities */
1307 put_unaligned_be16(0xffff, &buf[4]);
1308 /* Don't disable prefetch */
1309 /* Minimum prefetch = 0 */
1310 put_unaligned_be16(0xffff, &buf[8]);
1311 /* Maximum prefetch */
1312 put_unaligned_be16(0xffff, &buf[10]);
1313 /* Maximum prefetch ceiling */
1319 * Check that a valid page was requested and the mode data length
1323 if (!valid_page || len > limit) {
1324 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1328 /* Store the mode data length */
1329 if (mscmnd == MODE_SENSE)
1332 put_unaligned_be16(len - 2, buf0);
1336 static int do_start_stop(struct fsg_common *common)
1338 struct fsg_lun *curlun = common->curlun;
1343 } else if (!curlun->removable) {
1344 curlun->sense_data = SS_INVALID_COMMAND;
1346 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1347 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1348 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1352 loej = common->cmnd[4] & 0x02;
1353 start = common->cmnd[4] & 0x01;
1356 * Our emulation doesn't support mounting; the medium is
1357 * available for use as soon as it is loaded.
1360 if (!fsg_lun_is_open(curlun)) {
1361 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1367 /* Are we allowed to unload the media? */
1368 if (curlun->prevent_medium_removal) {
1369 LDBG(curlun, "unload attempt prevented\n");
1370 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1377 /* Simulate an unload/eject */
1378 if (common->ops && common->ops->pre_eject) {
1379 int r = common->ops->pre_eject(common, curlun,
1380 curlun - common->luns);
1381 if (unlikely(r < 0))
1387 up_read(&common->filesem);
1388 down_write(&common->filesem);
1389 fsg_lun_close(curlun);
1390 up_write(&common->filesem);
1391 down_read(&common->filesem);
1393 return common->ops && common->ops->post_eject
1394 ? min(0, common->ops->post_eject(common, curlun,
1395 curlun - common->luns))
1399 static int do_prevent_allow(struct fsg_common *common)
1401 struct fsg_lun *curlun = common->curlun;
1404 if (!common->curlun) {
1406 } else if (!common->curlun->removable) {
1407 common->curlun->sense_data = SS_INVALID_COMMAND;
1411 prevent = common->cmnd[4] & 0x01;
1412 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1413 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1417 if (curlun->prevent_medium_removal && !prevent)
1418 fsg_lun_fsync_sub(curlun);
1419 curlun->prevent_medium_removal = prevent;
1423 static int do_read_format_capacities(struct fsg_common *common,
1424 struct fsg_buffhd *bh)
1426 struct fsg_lun *curlun = common->curlun;
1427 u8 *buf = (u8 *) bh->buf;
1429 buf[0] = buf[1] = buf[2] = 0;
1430 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1433 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1434 /* Number of blocks */
1435 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1436 buf[4] = 0x02; /* Current capacity */
1440 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1442 struct fsg_lun *curlun = common->curlun;
1444 /* We don't support MODE SELECT */
1446 curlun->sense_data = SS_INVALID_COMMAND;
1451 /*-------------------------------------------------------------------------*/
1453 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1457 rc = fsg_set_halt(fsg, fsg->bulk_in);
1459 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1461 if (rc != -EAGAIN) {
1462 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1467 /* Wait for a short time and then try again */
1468 if (msleep_interruptible(100) != 0)
1470 rc = usb_ep_set_halt(fsg->bulk_in);
1475 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1479 DBG(fsg, "bulk-in set wedge\n");
1480 rc = usb_ep_set_wedge(fsg->bulk_in);
1482 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1484 if (rc != -EAGAIN) {
1485 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1490 /* Wait for a short time and then try again */
1491 if (msleep_interruptible(100) != 0)
1493 rc = usb_ep_set_wedge(fsg->bulk_in);
1498 static int throw_away_data(struct fsg_common *common)
1500 struct fsg_buffhd *bh;
1504 for (bh = common->next_buffhd_to_drain;
1505 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1506 bh = common->next_buffhd_to_drain) {
1508 /* Throw away the data in a filled buffer */
1509 if (bh->state == BUF_STATE_FULL) {
1511 bh->state = BUF_STATE_EMPTY;
1512 common->next_buffhd_to_drain = bh->next;
1514 /* A short packet or an error ends everything */
1515 if (bh->outreq->actual < bh->bulk_out_intended_length ||
1516 bh->outreq->status != 0) {
1517 raise_exception(common,
1518 FSG_STATE_ABORT_BULK_OUT);
1524 /* Try to submit another request if we need one */
1525 bh = common->next_buffhd_to_fill;
1526 if (bh->state == BUF_STATE_EMPTY
1527 && common->usb_amount_left > 0) {
1528 amount = min(common->usb_amount_left, FSG_BUFLEN);
1531 * Except at the end of the transfer, amount will be
1532 * equal to the buffer size, which is divisible by
1533 * the bulk-out maxpacket size.
1535 set_bulk_out_req_length(common, bh, amount);
1536 if (!start_out_transfer(common, bh))
1537 /* Dunno what to do if common->fsg is NULL */
1539 common->next_buffhd_to_fill = bh->next;
1540 common->usb_amount_left -= amount;
1544 /* Otherwise wait for something to happen */
1545 rc = sleep_thread(common);
1552 static int finish_reply(struct fsg_common *common)
1554 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1557 switch (common->data_dir) {
1559 break; /* Nothing to send */
1562 * If we don't know whether the host wants to read or write,
1563 * this must be CB or CBI with an unknown command. We mustn't
1564 * try to send or receive any data. So stall both bulk pipes
1565 * if we can and wait for a reset.
1567 case DATA_DIR_UNKNOWN:
1568 if (!common->can_stall) {
1570 } else if (fsg_is_set(common)) {
1571 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1572 rc = halt_bulk_in_endpoint(common->fsg);
1574 /* Don't know what to do if common->fsg is NULL */
1579 /* All but the last buffer of data must have already been sent */
1580 case DATA_DIR_TO_HOST:
1581 if (common->data_size == 0) {
1582 /* Nothing to send */
1584 /* Don't know what to do if common->fsg is NULL */
1585 } else if (!fsg_is_set(common)) {
1588 /* If there's no residue, simply send the last buffer */
1589 } else if (common->residue == 0) {
1590 bh->inreq->zero = 0;
1591 if (!start_in_transfer(common, bh))
1593 common->next_buffhd_to_fill = bh->next;
1596 * For Bulk-only, mark the end of the data with a short
1597 * packet. If we are allowed to stall, halt the bulk-in
1598 * endpoint. (Note: This violates the Bulk-Only Transport
1599 * specification, which requires us to pad the data if we
1600 * don't halt the endpoint. Presumably nobody will mind.)
1603 bh->inreq->zero = 1;
1604 if (!start_in_transfer(common, bh))
1606 common->next_buffhd_to_fill = bh->next;
1607 if (common->can_stall)
1608 rc = halt_bulk_in_endpoint(common->fsg);
1613 * We have processed all we want from the data the host has sent.
1614 * There may still be outstanding bulk-out requests.
1616 case DATA_DIR_FROM_HOST:
1617 if (common->residue == 0) {
1618 /* Nothing to receive */
1620 /* Did the host stop sending unexpectedly early? */
1621 } else if (common->short_packet_received) {
1622 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1626 * We haven't processed all the incoming data. Even though
1627 * we may be allowed to stall, doing so would cause a race.
1628 * The controller may already have ACK'ed all the remaining
1629 * bulk-out packets, in which case the host wouldn't see a
1630 * STALL. Not realizing the endpoint was halted, it wouldn't
1631 * clear the halt -- leading to problems later on.
1634 } else if (common->can_stall) {
1635 if (fsg_is_set(common))
1636 fsg_set_halt(common->fsg,
1637 common->fsg->bulk_out);
1638 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1643 * We can't stall. Read in the excess data and throw it
1647 rc = throw_away_data(common);
1654 static int send_status(struct fsg_common *common)
1656 struct fsg_lun *curlun = common->curlun;
1657 struct fsg_buffhd *bh;
1658 struct bulk_cs_wrap *csw;
1660 u8 status = US_BULK_STAT_OK;
1663 /* Wait for the next buffer to become available */
1664 bh = common->next_buffhd_to_fill;
1665 while (bh->state != BUF_STATE_EMPTY) {
1666 rc = sleep_thread(common);
1672 sd = curlun->sense_data;
1673 sdinfo = curlun->sense_data_info;
1674 } else if (common->bad_lun_okay)
1677 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1679 if (common->phase_error) {
1680 DBG(common, "sending phase-error status\n");
1681 status = US_BULK_STAT_PHASE;
1682 sd = SS_INVALID_COMMAND;
1683 } else if (sd != SS_NO_SENSE) {
1684 DBG(common, "sending command-failure status\n");
1685 status = US_BULK_STAT_FAIL;
1686 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1688 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1691 /* Store and send the Bulk-only CSW */
1692 csw = (void *)bh->buf;
1694 csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
1695 csw->Tag = common->tag;
1696 csw->Residue = cpu_to_le32(common->residue);
1697 csw->Status = status;
1699 bh->inreq->length = US_BULK_CS_WRAP_LEN;
1700 bh->inreq->zero = 0;
1701 if (!start_in_transfer(common, bh))
1702 /* Don't know what to do if common->fsg is NULL */
1705 common->next_buffhd_to_fill = bh->next;
1710 /*-------------------------------------------------------------------------*/
1713 * Check whether the command is properly formed and whether its data size
1714 * and direction agree with the values we already have.
1716 static int check_command(struct fsg_common *common, int cmnd_size,
1717 enum data_direction data_dir, unsigned int mask,
1718 int needs_medium, const char *name)
1721 int lun = common->cmnd[1] >> 5;
1722 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1724 struct fsg_lun *curlun;
1727 if (common->data_dir != DATA_DIR_UNKNOWN)
1728 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1730 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1731 name, cmnd_size, dirletter[(int) data_dir],
1732 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1735 * We can't reply at all until we know the correct data direction
1738 if (common->data_size_from_cmnd == 0)
1739 data_dir = DATA_DIR_NONE;
1740 if (common->data_size < common->data_size_from_cmnd) {
1742 * Host data size < Device data size is a phase error.
1743 * Carry out the command, but only transfer as much as
1746 common->data_size_from_cmnd = common->data_size;
1747 common->phase_error = 1;
1749 common->residue = common->data_size;
1750 common->usb_amount_left = common->data_size;
1752 /* Conflicting data directions is a phase error */
1753 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1754 common->phase_error = 1;
1758 /* Verify the length of the command itself */
1759 if (cmnd_size != common->cmnd_size) {
1762 * Special case workaround: There are plenty of buggy SCSI
1763 * implementations. Many have issues with cbw->Length
1764 * field passing a wrong command size. For those cases we
1765 * always try to work around the problem by using the length
1766 * sent by the host side provided it is at least as large
1767 * as the correct command length.
1768 * Examples of such cases would be MS-Windows, which issues
1769 * REQUEST SENSE with cbw->Length == 12 where it should
1770 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1771 * REQUEST SENSE with cbw->Length == 10 where it should
1774 if (cmnd_size <= common->cmnd_size) {
1775 DBG(common, "%s is buggy! Expected length %d "
1776 "but we got %d\n", name,
1777 cmnd_size, common->cmnd_size);
1778 cmnd_size = common->cmnd_size;
1780 common->phase_error = 1;
1785 /* Check that the LUN values are consistent */
1786 if (common->lun != lun)
1787 DBG(common, "using LUN %d from CBW, not LUN %d from CDB\n",
1791 curlun = common->curlun;
1793 if (common->cmnd[0] != REQUEST_SENSE) {
1794 curlun->sense_data = SS_NO_SENSE;
1795 curlun->sense_data_info = 0;
1796 curlun->info_valid = 0;
1799 common->bad_lun_okay = 0;
1802 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1803 * to use unsupported LUNs; all others may not.
1805 if (common->cmnd[0] != INQUIRY &&
1806 common->cmnd[0] != REQUEST_SENSE) {
1807 DBG(common, "unsupported LUN %d\n", common->lun);
1813 * If a unit attention condition exists, only INQUIRY and
1814 * REQUEST SENSE commands are allowed; anything else must fail.
1816 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1817 common->cmnd[0] != INQUIRY &&
1818 common->cmnd[0] != REQUEST_SENSE) {
1819 curlun->sense_data = curlun->unit_attention_data;
1820 curlun->unit_attention_data = SS_NO_SENSE;
1824 /* Check that only command bytes listed in the mask are non-zero */
1825 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1826 for (i = 1; i < cmnd_size; ++i) {
1827 if (common->cmnd[i] && !(mask & (1 << i))) {
1829 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1834 /* If the medium isn't mounted and the command needs to access
1835 * it, return an error. */
1836 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1837 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1844 /* wrapper of check_command for data size in blocks handling */
1845 static int check_command_size_in_blocks(struct fsg_common *common,
1846 int cmnd_size, enum data_direction data_dir,
1847 unsigned int mask, int needs_medium, const char *name)
1850 common->data_size_from_cmnd <<= common->curlun->blkbits;
1851 return check_command(common, cmnd_size, data_dir,
1852 mask, needs_medium, name);
1855 static int do_scsi_command(struct fsg_common *common)
1857 struct fsg_buffhd *bh;
1859 int reply = -EINVAL;
1861 static char unknown[16];
1865 /* Wait for the next buffer to become available for data or status */
1866 bh = common->next_buffhd_to_fill;
1867 common->next_buffhd_to_drain = bh;
1868 while (bh->state != BUF_STATE_EMPTY) {
1869 rc = sleep_thread(common);
1873 common->phase_error = 0;
1874 common->short_packet_received = 0;
1876 down_read(&common->filesem); /* We're using the backing file */
1877 switch (common->cmnd[0]) {
1880 common->data_size_from_cmnd = common->cmnd[4];
1881 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1885 reply = do_inquiry(common, bh);
1889 common->data_size_from_cmnd = common->cmnd[4];
1890 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1894 reply = do_mode_select(common, bh);
1897 case MODE_SELECT_10:
1898 common->data_size_from_cmnd =
1899 get_unaligned_be16(&common->cmnd[7]);
1900 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1904 reply = do_mode_select(common, bh);
1908 common->data_size_from_cmnd = common->cmnd[4];
1909 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1910 (1<<1) | (1<<2) | (1<<4), 0,
1913 reply = do_mode_sense(common, bh);
1917 common->data_size_from_cmnd =
1918 get_unaligned_be16(&common->cmnd[7]);
1919 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1920 (1<<1) | (1<<2) | (3<<7), 0,
1923 reply = do_mode_sense(common, bh);
1926 case ALLOW_MEDIUM_REMOVAL:
1927 common->data_size_from_cmnd = 0;
1928 reply = check_command(common, 6, DATA_DIR_NONE,
1930 "PREVENT-ALLOW MEDIUM REMOVAL");
1932 reply = do_prevent_allow(common);
1936 i = common->cmnd[4];
1937 common->data_size_from_cmnd = (i == 0) ? 256 : i;
1938 reply = check_command_size_in_blocks(common, 6,
1943 reply = do_read(common);
1947 common->data_size_from_cmnd =
1948 get_unaligned_be16(&common->cmnd[7]);
1949 reply = check_command_size_in_blocks(common, 10,
1951 (1<<1) | (0xf<<2) | (3<<7), 1,
1954 reply = do_read(common);
1958 common->data_size_from_cmnd =
1959 get_unaligned_be32(&common->cmnd[6]);
1960 reply = check_command_size_in_blocks(common, 12,
1962 (1<<1) | (0xf<<2) | (0xf<<6), 1,
1965 reply = do_read(common);
1969 common->data_size_from_cmnd = 8;
1970 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1971 (0xf<<2) | (1<<8), 1,
1974 reply = do_read_capacity(common, bh);
1978 if (!common->curlun || !common->curlun->cdrom)
1980 common->data_size_from_cmnd =
1981 get_unaligned_be16(&common->cmnd[7]);
1982 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1983 (3<<7) | (0x1f<<1), 1,
1986 reply = do_read_header(common, bh);
1990 if (!common->curlun || !common->curlun->cdrom)
1992 common->data_size_from_cmnd =
1993 get_unaligned_be16(&common->cmnd[7]);
1994 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1998 reply = do_read_toc(common, bh);
2001 case READ_FORMAT_CAPACITIES:
2002 common->data_size_from_cmnd =
2003 get_unaligned_be16(&common->cmnd[7]);
2004 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2006 "READ FORMAT CAPACITIES");
2008 reply = do_read_format_capacities(common, bh);
2012 common->data_size_from_cmnd = common->cmnd[4];
2013 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2017 reply = do_request_sense(common, bh);
2021 common->data_size_from_cmnd = 0;
2022 reply = check_command(common, 6, DATA_DIR_NONE,
2026 reply = do_start_stop(common);
2029 case SYNCHRONIZE_CACHE:
2030 common->data_size_from_cmnd = 0;
2031 reply = check_command(common, 10, DATA_DIR_NONE,
2032 (0xf<<2) | (3<<7), 1,
2033 "SYNCHRONIZE CACHE");
2035 reply = do_synchronize_cache(common);
2038 case TEST_UNIT_READY:
2039 common->data_size_from_cmnd = 0;
2040 reply = check_command(common, 6, DATA_DIR_NONE,
2046 * Although optional, this command is used by MS-Windows. We
2047 * support a minimal version: BytChk must be 0.
2050 common->data_size_from_cmnd = 0;
2051 reply = check_command(common, 10, DATA_DIR_NONE,
2052 (1<<1) | (0xf<<2) | (3<<7), 1,
2055 reply = do_verify(common);
2059 i = common->cmnd[4];
2060 common->data_size_from_cmnd = (i == 0) ? 256 : i;
2061 reply = check_command_size_in_blocks(common, 6,
2066 reply = do_write(common);
2070 common->data_size_from_cmnd =
2071 get_unaligned_be16(&common->cmnd[7]);
2072 reply = check_command_size_in_blocks(common, 10,
2074 (1<<1) | (0xf<<2) | (3<<7), 1,
2077 reply = do_write(common);
2081 common->data_size_from_cmnd =
2082 get_unaligned_be32(&common->cmnd[6]);
2083 reply = check_command_size_in_blocks(common, 12,
2085 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2088 reply = do_write(common);
2092 * Some mandatory commands that we recognize but don't implement.
2093 * They don't mean much in this setting. It's left as an exercise
2094 * for anyone interested to implement RESERVE and RELEASE in terms
2100 case SEND_DIAGNOSTIC:
2105 common->data_size_from_cmnd = 0;
2106 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2107 reply = check_command(common, common->cmnd_size,
2108 DATA_DIR_UNKNOWN, ~0, 0, unknown);
2110 common->curlun->sense_data = SS_INVALID_COMMAND;
2115 up_read(&common->filesem);
2117 if (reply == -EINTR || signal_pending(current))
2120 /* Set up the single reply buffer for finish_reply() */
2121 if (reply == -EINVAL)
2122 reply = 0; /* Error reply length */
2123 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2124 reply = min((u32)reply, common->data_size_from_cmnd);
2125 bh->inreq->length = reply;
2126 bh->state = BUF_STATE_FULL;
2127 common->residue -= reply;
2128 } /* Otherwise it's already set */
2134 /*-------------------------------------------------------------------------*/
2136 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2138 struct usb_request *req = bh->outreq;
2139 struct bulk_cb_wrap *cbw = req->buf;
2140 struct fsg_common *common = fsg->common;
2142 /* Was this a real packet? Should it be ignored? */
2143 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2146 /* Is the CBW valid? */
2147 if (req->actual != US_BULK_CB_WRAP_LEN ||
2148 cbw->Signature != cpu_to_le32(
2150 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2152 le32_to_cpu(cbw->Signature));
2155 * The Bulk-only spec says we MUST stall the IN endpoint
2156 * (6.6.1), so it's unavoidable. It also says we must
2157 * retain this state until the next reset, but there's
2158 * no way to tell the controller driver it should ignore
2159 * Clear-Feature(HALT) requests.
2161 * We aren't required to halt the OUT endpoint; instead
2162 * we can simply accept and discard any data received
2163 * until the next reset.
2165 wedge_bulk_in_endpoint(fsg);
2166 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2170 /* Is the CBW meaningful? */
2171 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~US_BULK_FLAG_IN ||
2172 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2173 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2175 cbw->Lun, cbw->Flags, cbw->Length);
2178 * We can do anything we want here, so let's stall the
2179 * bulk pipes if we are allowed to.
2181 if (common->can_stall) {
2182 fsg_set_halt(fsg, fsg->bulk_out);
2183 halt_bulk_in_endpoint(fsg);
2188 /* Save the command for later */
2189 common->cmnd_size = cbw->Length;
2190 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2191 if (cbw->Flags & US_BULK_FLAG_IN)
2192 common->data_dir = DATA_DIR_TO_HOST;
2194 common->data_dir = DATA_DIR_FROM_HOST;
2195 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2196 if (common->data_size == 0)
2197 common->data_dir = DATA_DIR_NONE;
2198 common->lun = cbw->Lun;
2199 if (common->lun >= 0 && common->lun < common->nluns)
2200 common->curlun = &common->luns[common->lun];
2202 common->curlun = NULL;
2203 common->tag = cbw->Tag;
2207 static int get_next_command(struct fsg_common *common)
2209 struct fsg_buffhd *bh;
2212 /* Wait for the next buffer to become available */
2213 bh = common->next_buffhd_to_fill;
2214 while (bh->state != BUF_STATE_EMPTY) {
2215 rc = sleep_thread(common);
2220 /* Queue a request to read a Bulk-only CBW */
2221 set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
2222 if (!start_out_transfer(common, bh))
2223 /* Don't know what to do if common->fsg is NULL */
2227 * We will drain the buffer in software, which means we
2228 * can reuse it for the next filling. No need to advance
2229 * next_buffhd_to_fill.
2232 /* Wait for the CBW to arrive */
2233 while (bh->state != BUF_STATE_FULL) {
2234 rc = sleep_thread(common);
2239 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2240 bh->state = BUF_STATE_EMPTY;
2246 /*-------------------------------------------------------------------------*/
2248 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2249 struct usb_request **preq)
2251 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2254 ERROR(common, "can't allocate request for %s\n", ep->name);
2258 /* Reset interface setting and re-init endpoint state (toggle etc). */
2259 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2261 struct fsg_dev *fsg;
2264 if (common->running)
2265 DBG(common, "reset interface\n");
2268 /* Deallocate the requests */
2272 for (i = 0; i < fsg_num_buffers; ++i) {
2273 struct fsg_buffhd *bh = &common->buffhds[i];
2276 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2280 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2285 /* Disable the endpoints */
2286 if (fsg->bulk_in_enabled) {
2287 usb_ep_disable(fsg->bulk_in);
2288 fsg->bulk_in_enabled = 0;
2290 if (fsg->bulk_out_enabled) {
2291 usb_ep_disable(fsg->bulk_out);
2292 fsg->bulk_out_enabled = 0;
2296 wake_up(&common->fsg_wait);
2299 common->running = 0;
2303 common->fsg = new_fsg;
2306 /* Enable the endpoints */
2307 rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
2310 rc = usb_ep_enable(fsg->bulk_in);
2313 fsg->bulk_in->driver_data = common;
2314 fsg->bulk_in_enabled = 1;
2316 rc = config_ep_by_speed(common->gadget, &(fsg->function),
2320 rc = usb_ep_enable(fsg->bulk_out);
2323 fsg->bulk_out->driver_data = common;
2324 fsg->bulk_out_enabled = 1;
2325 common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc);
2326 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2328 /* Allocate the requests */
2329 for (i = 0; i < fsg_num_buffers; ++i) {
2330 struct fsg_buffhd *bh = &common->buffhds[i];
2332 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2335 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2338 bh->inreq->buf = bh->outreq->buf = bh->buf;
2339 bh->inreq->context = bh->outreq->context = bh;
2340 bh->inreq->complete = bulk_in_complete;
2341 bh->outreq->complete = bulk_out_complete;
2344 common->running = 1;
2345 for (i = 0; i < common->nluns; ++i)
2346 common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
2351 /****************************** ALT CONFIGS ******************************/
2353 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2355 struct fsg_dev *fsg = fsg_from_func(f);
2356 fsg->common->new_fsg = fsg;
2357 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2358 return USB_GADGET_DELAYED_STATUS;
2361 static void fsg_disable(struct usb_function *f)
2363 struct fsg_dev *fsg = fsg_from_func(f);
2364 fsg->common->new_fsg = NULL;
2365 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2369 /*-------------------------------------------------------------------------*/
2371 static void handle_exception(struct fsg_common *common)
2375 struct fsg_buffhd *bh;
2376 enum fsg_state old_state;
2377 struct fsg_lun *curlun;
2378 unsigned int exception_req_tag;
2381 * Clear the existing signals. Anything but SIGUSR1 is converted
2382 * into a high-priority EXIT exception.
2386 dequeue_signal_lock(current, ¤t->blocked, &info);
2389 if (sig != SIGUSR1) {
2390 if (common->state < FSG_STATE_EXIT)
2391 DBG(common, "Main thread exiting on signal\n");
2392 raise_exception(common, FSG_STATE_EXIT);
2396 /* Cancel all the pending transfers */
2397 if (likely(common->fsg)) {
2398 for (i = 0; i < fsg_num_buffers; ++i) {
2399 bh = &common->buffhds[i];
2401 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2402 if (bh->outreq_busy)
2403 usb_ep_dequeue(common->fsg->bulk_out,
2407 /* Wait until everything is idle */
2410 for (i = 0; i < fsg_num_buffers; ++i) {
2411 bh = &common->buffhds[i];
2412 num_active += bh->inreq_busy + bh->outreq_busy;
2414 if (num_active == 0)
2416 if (sleep_thread(common))
2420 /* Clear out the controller's fifos */
2421 if (common->fsg->bulk_in_enabled)
2422 usb_ep_fifo_flush(common->fsg->bulk_in);
2423 if (common->fsg->bulk_out_enabled)
2424 usb_ep_fifo_flush(common->fsg->bulk_out);
2428 * Reset the I/O buffer states and pointers, the SCSI
2429 * state, and the exception. Then invoke the handler.
2431 spin_lock_irq(&common->lock);
2433 for (i = 0; i < fsg_num_buffers; ++i) {
2434 bh = &common->buffhds[i];
2435 bh->state = BUF_STATE_EMPTY;
2437 common->next_buffhd_to_fill = &common->buffhds[0];
2438 common->next_buffhd_to_drain = &common->buffhds[0];
2439 exception_req_tag = common->exception_req_tag;
2440 old_state = common->state;
2442 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2443 common->state = FSG_STATE_STATUS_PHASE;
2445 for (i = 0; i < common->nluns; ++i) {
2446 curlun = &common->luns[i];
2447 curlun->prevent_medium_removal = 0;
2448 curlun->sense_data = SS_NO_SENSE;
2449 curlun->unit_attention_data = SS_NO_SENSE;
2450 curlun->sense_data_info = 0;
2451 curlun->info_valid = 0;
2453 common->state = FSG_STATE_IDLE;
2455 spin_unlock_irq(&common->lock);
2457 /* Carry out any extra actions required for the exception */
2458 switch (old_state) {
2459 case FSG_STATE_ABORT_BULK_OUT:
2460 send_status(common);
2461 spin_lock_irq(&common->lock);
2462 if (common->state == FSG_STATE_STATUS_PHASE)
2463 common->state = FSG_STATE_IDLE;
2464 spin_unlock_irq(&common->lock);
2467 case FSG_STATE_RESET:
2469 * In case we were forced against our will to halt a
2470 * bulk endpoint, clear the halt now. (The SuperH UDC
2473 if (!fsg_is_set(common))
2475 if (test_and_clear_bit(IGNORE_BULK_OUT,
2476 &common->fsg->atomic_bitflags))
2477 usb_ep_clear_halt(common->fsg->bulk_in);
2479 if (common->ep0_req_tag == exception_req_tag)
2480 ep0_queue(common); /* Complete the status stage */
2483 * Technically this should go here, but it would only be
2484 * a waste of time. Ditto for the INTERFACE_CHANGE and
2485 * CONFIG_CHANGE cases.
2487 /* for (i = 0; i < common->nluns; ++i) */
2488 /* common->luns[i].unit_attention_data = */
2489 /* SS_RESET_OCCURRED; */
2492 case FSG_STATE_CONFIG_CHANGE:
2493 do_set_interface(common, common->new_fsg);
2494 if (common->new_fsg)
2495 usb_composite_setup_continue(common->cdev);
2498 case FSG_STATE_EXIT:
2499 case FSG_STATE_TERMINATED:
2500 do_set_interface(common, NULL); /* Free resources */
2501 spin_lock_irq(&common->lock);
2502 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2503 spin_unlock_irq(&common->lock);
2506 case FSG_STATE_INTERFACE_CHANGE:
2507 case FSG_STATE_DISCONNECT:
2508 case FSG_STATE_COMMAND_PHASE:
2509 case FSG_STATE_DATA_PHASE:
2510 case FSG_STATE_STATUS_PHASE:
2511 case FSG_STATE_IDLE:
2517 /*-------------------------------------------------------------------------*/
2519 static int fsg_main_thread(void *common_)
2521 struct fsg_common *common = common_;
2524 * Allow the thread to be killed by a signal, but set the signal mask
2525 * to block everything but INT, TERM, KILL, and USR1.
2527 allow_signal(SIGINT);
2528 allow_signal(SIGTERM);
2529 allow_signal(SIGKILL);
2530 allow_signal(SIGUSR1);
2532 /* Allow the thread to be frozen */
2536 * Arrange for userspace references to be interpreted as kernel
2537 * pointers. That way we can pass a kernel pointer to a routine
2538 * that expects a __user pointer and it will work okay.
2543 while (common->state != FSG_STATE_TERMINATED) {
2544 if (exception_in_progress(common) || signal_pending(current)) {
2545 handle_exception(common);
2549 if (!common->running) {
2550 sleep_thread(common);
2554 if (get_next_command(common))
2557 spin_lock_irq(&common->lock);
2558 if (!exception_in_progress(common))
2559 common->state = FSG_STATE_DATA_PHASE;
2560 spin_unlock_irq(&common->lock);
2562 if (do_scsi_command(common) || finish_reply(common))
2565 spin_lock_irq(&common->lock);
2566 if (!exception_in_progress(common))
2567 common->state = FSG_STATE_STATUS_PHASE;
2568 spin_unlock_irq(&common->lock);
2570 if (send_status(common))
2573 spin_lock_irq(&common->lock);
2574 if (!exception_in_progress(common))
2575 common->state = FSG_STATE_IDLE;
2576 spin_unlock_irq(&common->lock);
2579 spin_lock_irq(&common->lock);
2580 common->thread_task = NULL;
2581 spin_unlock_irq(&common->lock);
2583 if (!common->ops || !common->ops->thread_exits
2584 || common->ops->thread_exits(common) < 0) {
2585 struct fsg_lun *curlun = common->luns;
2586 unsigned i = common->nluns;
2588 down_write(&common->filesem);
2589 for (; i--; ++curlun) {
2590 if (!fsg_lun_is_open(curlun))
2593 fsg_lun_close(curlun);
2594 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
2596 up_write(&common->filesem);
2599 /* Let fsg_unbind() know the thread has exited */
2600 complete_and_exit(&common->thread_notifier, 0);
2604 /*************************** DEVICE ATTRIBUTES ***************************/
2606 static DEVICE_ATTR(ro, 0644, fsg_show_ro, fsg_store_ro);
2607 static DEVICE_ATTR(nofua, 0644, fsg_show_nofua, fsg_store_nofua);
2608 static DEVICE_ATTR(file, 0644, fsg_show_file, fsg_store_file);
2610 static struct device_attribute dev_attr_ro_cdrom =
2611 __ATTR(ro, 0444, fsg_show_ro, NULL);
2612 static struct device_attribute dev_attr_file_nonremovable =
2613 __ATTR(file, 0444, fsg_show_file, NULL);
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 static inline void fsg_common_get(struct fsg_common *common)
2627 kref_get(&common->ref);
2630 static inline void fsg_common_put(struct fsg_common *common)
2632 kref_put(&common->ref, fsg_common_release);
2635 static struct fsg_common *fsg_common_init(struct fsg_common *common,
2636 struct usb_composite_dev *cdev,
2637 struct fsg_config *cfg)
2639 struct usb_gadget *gadget = cdev->gadget;
2640 struct fsg_buffhd *bh;
2641 struct fsg_lun *curlun;
2642 struct fsg_lun_config *lcfg;
2646 rc = fsg_num_buffers_validate();
2650 /* Find out how many LUNs there should be */
2652 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2653 dev_err(&gadget->dev, "invalid number of LUNs: %u\n", nluns);
2654 return ERR_PTR(-EINVAL);
2659 common = kzalloc(sizeof *common, GFP_KERNEL);
2661 return ERR_PTR(-ENOMEM);
2662 common->free_storage_on_release = 1;
2664 memset(common, 0, sizeof *common);
2665 common->free_storage_on_release = 0;
2668 common->buffhds = kcalloc(fsg_num_buffers,
2669 sizeof *(common->buffhds), GFP_KERNEL);
2670 if (!common->buffhds) {
2671 if (common->free_storage_on_release)
2673 return ERR_PTR(-ENOMEM);
2676 common->ops = cfg->ops;
2677 common->private_data = cfg->private_data;
2679 common->gadget = gadget;
2680 common->ep0 = gadget->ep0;
2681 common->ep0req = cdev->req;
2682 common->cdev = cdev;
2684 /* Maybe allocate device-global string IDs, and patch descriptors */
2685 if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
2686 rc = usb_string_id(cdev);
2687 if (unlikely(rc < 0))
2689 fsg_strings[FSG_STRING_INTERFACE].id = rc;
2690 fsg_intf_desc.iInterface = rc;
2694 * Create the LUNs, open their backing files, and register the
2695 * LUN devices in sysfs.
2697 curlun = kcalloc(nluns, sizeof(*curlun), GFP_KERNEL);
2698 if (unlikely(!curlun)) {
2702 common->luns = curlun;
2704 init_rwsem(&common->filesem);
2706 for (i = 0, lcfg = cfg->luns; i < nluns; ++i, ++curlun, ++lcfg) {
2707 curlun->cdrom = !!lcfg->cdrom;
2708 curlun->ro = lcfg->cdrom || lcfg->ro;
2709 curlun->initially_ro = curlun->ro;
2710 curlun->removable = lcfg->removable;
2711 curlun->dev.release = fsg_lun_release;
2712 curlun->dev.parent = &gadget->dev;
2713 /* curlun->dev.driver = &fsg_driver.driver; XXX */
2714 dev_set_drvdata(&curlun->dev, &common->filesem);
2715 dev_set_name(&curlun->dev, "lun%d", i);
2717 rc = device_register(&curlun->dev);
2719 INFO(common, "failed to register LUN%d: %d\n", i, rc);
2721 put_device(&curlun->dev);
2725 rc = device_create_file(&curlun->dev,
2727 ? &dev_attr_ro_cdrom
2731 rc = device_create_file(&curlun->dev,
2734 : &dev_attr_file_nonremovable);
2737 rc = device_create_file(&curlun->dev, &dev_attr_nofua);
2741 if (lcfg->filename) {
2742 rc = fsg_lun_open(curlun, lcfg->filename);
2745 } else if (!curlun->removable) {
2746 ERROR(common, "no file given for LUN%d\n", i);
2751 common->nluns = nluns;
2753 /* Data buffers cyclic list */
2754 bh = common->buffhds;
2755 i = fsg_num_buffers;
2756 goto buffhds_first_it;
2761 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2762 if (unlikely(!bh->buf)) {
2767 bh->next = common->buffhds;
2769 /* Prepare inquiryString */
2770 i = get_default_bcdDevice();
2771 snprintf(common->inquiry_string, sizeof common->inquiry_string,
2772 "%-8s%-16s%04x", cfg->vendor_name ?: "Linux",
2773 /* Assume product name dependent on the first LUN */
2774 cfg->product_name ?: (common->luns->cdrom
2775 ? "File-Stor Gadget"
2776 : "File-CD Gadget"),
2780 * Some peripheral controllers are known not to be able to
2781 * halt bulk endpoints correctly. If one of them is present,
2784 common->can_stall = cfg->can_stall &&
2785 !(gadget_is_at91(common->gadget));
2787 spin_lock_init(&common->lock);
2788 kref_init(&common->ref);
2790 /* Tell the thread to start working */
2791 common->thread_task =
2792 kthread_create(fsg_main_thread, common, "file-storage");
2793 if (IS_ERR(common->thread_task)) {
2794 rc = PTR_ERR(common->thread_task);
2797 init_completion(&common->thread_notifier);
2798 init_waitqueue_head(&common->fsg_wait);
2801 INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2802 INFO(common, "Number of LUNs=%d\n", common->nluns);
2804 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2805 for (i = 0, nluns = common->nluns, curlun = common->luns;
2808 char *p = "(no medium)";
2809 if (fsg_lun_is_open(curlun)) {
2812 p = d_path(&curlun->filp->f_path,
2818 LINFO(curlun, "LUN: %s%s%sfile: %s\n",
2819 curlun->removable ? "removable " : "",
2820 curlun->ro ? "read only " : "",
2821 curlun->cdrom ? "CD-ROM " : "",
2826 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
2828 wake_up_process(common->thread_task);
2833 common->nluns = i + 1;
2835 common->state = FSG_STATE_TERMINATED; /* The thread is dead */
2836 /* Call fsg_common_release() directly, ref might be not initialised. */
2837 fsg_common_release(&common->ref);
2841 static void fsg_common_release(struct kref *ref)
2843 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
2845 /* If the thread isn't already dead, tell it to exit now */
2846 if (common->state != FSG_STATE_TERMINATED) {
2847 raise_exception(common, FSG_STATE_EXIT);
2848 wait_for_completion(&common->thread_notifier);
2851 if (likely(common->luns)) {
2852 struct fsg_lun *lun = common->luns;
2853 unsigned i = common->nluns;
2855 /* In error recovery common->nluns may be zero. */
2856 for (; i; --i, ++lun) {
2857 device_remove_file(&lun->dev, &dev_attr_nofua);
2858 device_remove_file(&lun->dev,
2860 ? &dev_attr_ro_cdrom
2862 device_remove_file(&lun->dev,
2865 : &dev_attr_file_nonremovable);
2867 device_unregister(&lun->dev);
2870 kfree(common->luns);
2874 struct fsg_buffhd *bh = common->buffhds;
2875 unsigned i = fsg_num_buffers;
2878 } while (++bh, --i);
2881 kfree(common->buffhds);
2882 if (common->free_storage_on_release)
2887 /*-------------------------------------------------------------------------*/
2889 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
2891 struct fsg_dev *fsg = fsg_from_func(f);
2892 struct fsg_common *common = fsg->common;
2894 DBG(fsg, "unbind\n");
2895 if (fsg->common->fsg == fsg) {
2896 fsg->common->new_fsg = NULL;
2897 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2898 /* FIXME: make interruptible or killable somehow? */
2899 wait_event(common->fsg_wait, common->fsg != fsg);
2902 fsg_common_put(common);
2903 usb_free_all_descriptors(&fsg->function);
2907 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
2909 struct fsg_dev *fsg = fsg_from_func(f);
2910 struct usb_gadget *gadget = c->cdev->gadget;
2916 fsg->gadget = gadget;
2919 i = usb_interface_id(c, f);
2922 fsg_intf_desc.bInterfaceNumber = i;
2923 fsg->interface_number = i;
2925 /* Find all the endpoints we will use */
2926 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
2929 ep->driver_data = fsg->common; /* claim the endpoint */
2932 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
2935 ep->driver_data = fsg->common; /* claim the endpoint */
2938 /* Assume endpoint addresses are the same for both speeds */
2939 fsg_hs_bulk_in_desc.bEndpointAddress =
2940 fsg_fs_bulk_in_desc.bEndpointAddress;
2941 fsg_hs_bulk_out_desc.bEndpointAddress =
2942 fsg_fs_bulk_out_desc.bEndpointAddress;
2944 /* Calculate bMaxBurst, we know packet size is 1024 */
2945 max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15);
2947 fsg_ss_bulk_in_desc.bEndpointAddress =
2948 fsg_fs_bulk_in_desc.bEndpointAddress;
2949 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
2951 fsg_ss_bulk_out_desc.bEndpointAddress =
2952 fsg_fs_bulk_out_desc.bEndpointAddress;
2953 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
2955 ret = usb_assign_descriptors(f, fsg_fs_function, fsg_hs_function,
2963 ERROR(fsg, "unable to autoconfigure all endpoints\n");
2967 /****************************** ADD FUNCTION ******************************/
2969 static struct usb_gadget_strings *fsg_strings_array[] = {
2974 static int fsg_bind_config(struct usb_composite_dev *cdev,
2975 struct usb_configuration *c,
2976 struct fsg_common *common)
2978 struct fsg_dev *fsg;
2981 fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
2985 fsg->function.name = FSG_DRIVER_DESC;
2986 fsg->function.strings = fsg_strings_array;
2987 fsg->function.bind = fsg_bind;
2988 fsg->function.unbind = fsg_unbind;
2989 fsg->function.setup = fsg_setup;
2990 fsg->function.set_alt = fsg_set_alt;
2991 fsg->function.disable = fsg_disable;
2993 fsg->common = common;
2995 * Our caller holds a reference to common structure so we
2996 * don't have to be worry about it being freed until we return
2997 * from this function. So instead of incrementing counter now
2998 * and decrement in error recovery we increment it only when
2999 * call to usb_add_function() was successful.
3002 rc = usb_add_function(c, &fsg->function);
3006 fsg_common_get(fsg->common);
3011 /************************* Module parameters *************************/
3013 struct fsg_module_parameters {
3014 char *file[FSG_MAX_LUNS];
3015 bool ro[FSG_MAX_LUNS];
3016 bool removable[FSG_MAX_LUNS];
3017 bool cdrom[FSG_MAX_LUNS];
3018 bool nofua[FSG_MAX_LUNS];
3020 unsigned int file_count, ro_count, removable_count, cdrom_count;
3021 unsigned int nofua_count;
3022 unsigned int luns; /* nluns */
3023 bool stall; /* can_stall */
3026 #define _FSG_MODULE_PARAM_ARRAY(prefix, params, name, type, desc) \
3027 module_param_array_named(prefix ## name, params.name, type, \
3028 &prefix ## params.name ## _count, \
3030 MODULE_PARM_DESC(prefix ## name, desc)
3032 #define _FSG_MODULE_PARAM(prefix, params, name, type, desc) \
3033 module_param_named(prefix ## name, params.name, type, \
3035 MODULE_PARM_DESC(prefix ## name, desc)
3037 #define FSG_MODULE_PARAMETERS(prefix, params) \
3038 _FSG_MODULE_PARAM_ARRAY(prefix, params, file, charp, \
3039 "names of backing files or devices"); \
3040 _FSG_MODULE_PARAM_ARRAY(prefix, params, ro, bool, \
3041 "true to force read-only"); \
3042 _FSG_MODULE_PARAM_ARRAY(prefix, params, removable, bool, \
3043 "true to simulate removable media"); \
3044 _FSG_MODULE_PARAM_ARRAY(prefix, params, cdrom, bool, \
3045 "true to simulate CD-ROM instead of disk"); \
3046 _FSG_MODULE_PARAM_ARRAY(prefix, params, nofua, bool, \
3047 "true to ignore SCSI WRITE(10,12) FUA bit"); \
3048 _FSG_MODULE_PARAM(prefix, params, luns, uint, \
3049 "number of LUNs"); \
3050 _FSG_MODULE_PARAM(prefix, params, stall, bool, \
3051 "false to prevent bulk stalls")
3054 fsg_config_from_params(struct fsg_config *cfg,
3055 const struct fsg_module_parameters *params)
3057 struct fsg_lun_config *lun;
3060 /* Configure LUNs */
3062 min(params->luns ?: (params->file_count ?: 1u),
3063 (unsigned)FSG_MAX_LUNS);
3064 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3065 lun->ro = !!params->ro[i];
3066 lun->cdrom = !!params->cdrom[i];
3067 lun->removable = !!params->removable[i];
3069 params->file_count > i && params->file[i][0]
3074 /* Let MSF use defaults */
3075 cfg->vendor_name = 0;
3076 cfg->product_name = 0;
3079 cfg->private_data = NULL;
3082 cfg->can_stall = params->stall;
3085 static inline struct fsg_common *
3086 fsg_common_from_params(struct fsg_common *common,
3087 struct usb_composite_dev *cdev,
3088 const struct fsg_module_parameters *params)
3089 __attribute__((unused));
3090 static inline struct fsg_common *
3091 fsg_common_from_params(struct fsg_common *common,
3092 struct usb_composite_dev *cdev,
3093 const struct fsg_module_parameters *params)
3095 struct fsg_config cfg;
3096 fsg_config_from_params(&cfg, params);
3097 return fsg_common_init(common, cdev, &cfg);