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
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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
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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.h"
232 #include "f_mass_storage.h"
234 /* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
235 static struct usb_string fsg_strings[] = {
236 {FSG_STRING_INTERFACE, fsg_string_interface},
240 static struct usb_gadget_strings fsg_stringtab = {
241 .language = 0x0409, /* en-us */
242 .strings = fsg_strings,
245 static struct usb_gadget_strings *fsg_strings_array[] = {
250 /*-------------------------------------------------------------------------*/
255 /* Data shared by all the FSG instances. */
257 struct usb_gadget *gadget;
258 struct usb_composite_dev *cdev;
259 struct fsg_dev *fsg, *new_fsg;
260 wait_queue_head_t fsg_wait;
262 /* filesem protects: backing files in use */
263 struct rw_semaphore filesem;
265 /* lock protects: state, all the req_busy's */
268 struct usb_ep *ep0; /* Copy of gadget->ep0 */
269 struct usb_request *ep0req; /* Copy of cdev->req */
270 unsigned int ep0_req_tag;
272 struct fsg_buffhd *next_buffhd_to_fill;
273 struct fsg_buffhd *next_buffhd_to_drain;
274 struct fsg_buffhd *buffhds;
275 unsigned int fsg_num_buffers;
278 u8 cmnd[MAX_COMMAND_SIZE];
282 struct fsg_lun **luns;
283 struct fsg_lun *curlun;
285 unsigned int bulk_out_maxpacket;
286 enum fsg_state state; /* For exception handling */
287 unsigned int exception_req_tag;
289 enum data_direction data_dir;
291 u32 data_size_from_cmnd;
296 unsigned int can_stall:1;
297 unsigned int free_storage_on_release:1;
298 unsigned int phase_error:1;
299 unsigned int short_packet_received:1;
300 unsigned int bad_lun_okay:1;
301 unsigned int running:1;
302 unsigned int sysfs:1;
304 int thread_wakeup_needed;
305 struct completion thread_notifier;
306 struct task_struct *thread_task;
308 /* Callback functions. */
309 const struct fsg_operations *ops;
310 /* Gadget's private data. */
314 * Vendor (8 chars), product (16 chars), release (4
315 * hexadecimal digits) and NUL byte
317 char inquiry_string[8 + 16 + 4 + 1];
323 struct usb_function function;
324 struct usb_gadget *gadget; /* Copy of cdev->gadget */
325 struct fsg_common *common;
327 u16 interface_number;
329 unsigned int bulk_in_enabled:1;
330 unsigned int bulk_out_enabled:1;
332 unsigned long atomic_bitflags;
333 #define IGNORE_BULK_OUT 0
335 struct usb_ep *bulk_in;
336 struct usb_ep *bulk_out;
339 static inline int __fsg_is_set(struct fsg_common *common,
340 const char *func, unsigned line)
344 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
349 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
351 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
353 return container_of(f, struct fsg_dev, function);
356 typedef void (*fsg_routine_t)(struct fsg_dev *);
358 static int exception_in_progress(struct fsg_common *common)
360 return common->state > FSG_STATE_IDLE;
363 /* Make bulk-out requests be divisible by the maxpacket size */
364 static void set_bulk_out_req_length(struct fsg_common *common,
365 struct fsg_buffhd *bh, unsigned int length)
369 bh->bulk_out_intended_length = length;
370 rem = length % common->bulk_out_maxpacket;
372 length += common->bulk_out_maxpacket - rem;
373 bh->outreq->length = length;
377 /*-------------------------------------------------------------------------*/
379 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
383 if (ep == fsg->bulk_in)
385 else if (ep == fsg->bulk_out)
389 DBG(fsg, "%s set halt\n", name);
390 return usb_ep_set_halt(ep);
394 /*-------------------------------------------------------------------------*/
396 /* These routines may be called in process context or in_irq */
398 /* Caller must hold fsg->lock */
399 static void wakeup_thread(struct fsg_common *common)
401 smp_wmb(); /* ensure the write of bh->state is complete */
402 /* Tell the main thread that something has happened */
403 common->thread_wakeup_needed = 1;
404 if (common->thread_task)
405 wake_up_process(common->thread_task);
408 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
413 * Do nothing if a higher-priority exception is already in progress.
414 * If a lower-or-equal priority exception is in progress, preempt it
415 * and notify the main thread by sending it a signal.
417 spin_lock_irqsave(&common->lock, flags);
418 if (common->state <= new_state) {
419 common->exception_req_tag = common->ep0_req_tag;
420 common->state = new_state;
421 if (common->thread_task)
422 send_sig_info(SIGUSR1, SEND_SIG_FORCED,
423 common->thread_task);
425 spin_unlock_irqrestore(&common->lock, flags);
429 /*-------------------------------------------------------------------------*/
431 static int ep0_queue(struct fsg_common *common)
435 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
436 common->ep0->driver_data = common;
437 if (rc != 0 && rc != -ESHUTDOWN) {
438 /* We can't do much more than wait for a reset */
439 WARNING(common, "error in submission: %s --> %d\n",
440 common->ep0->name, rc);
446 /*-------------------------------------------------------------------------*/
448 /* Completion handlers. These always run in_irq. */
450 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
452 struct fsg_common *common = ep->driver_data;
453 struct fsg_buffhd *bh = req->context;
455 if (req->status || req->actual != req->length)
456 DBG(common, "%s --> %d, %u/%u\n", __func__,
457 req->status, req->actual, req->length);
458 if (req->status == -ECONNRESET) /* Request was cancelled */
459 usb_ep_fifo_flush(ep);
461 /* Hold the lock while we update the request and buffer states */
463 spin_lock(&common->lock);
465 bh->state = BUF_STATE_EMPTY;
466 wakeup_thread(common);
467 spin_unlock(&common->lock);
470 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
472 struct fsg_common *common = ep->driver_data;
473 struct fsg_buffhd *bh = req->context;
475 dump_msg(common, "bulk-out", req->buf, req->actual);
476 if (req->status || req->actual != bh->bulk_out_intended_length)
477 DBG(common, "%s --> %d, %u/%u\n", __func__,
478 req->status, req->actual, bh->bulk_out_intended_length);
479 if (req->status == -ECONNRESET) /* Request was cancelled */
480 usb_ep_fifo_flush(ep);
482 /* Hold the lock while we update the request and buffer states */
484 spin_lock(&common->lock);
486 bh->state = BUF_STATE_FULL;
487 wakeup_thread(common);
488 spin_unlock(&common->lock);
491 static int fsg_setup(struct usb_function *f,
492 const struct usb_ctrlrequest *ctrl)
494 struct fsg_dev *fsg = fsg_from_func(f);
495 struct usb_request *req = fsg->common->ep0req;
496 u16 w_index = le16_to_cpu(ctrl->wIndex);
497 u16 w_value = le16_to_cpu(ctrl->wValue);
498 u16 w_length = le16_to_cpu(ctrl->wLength);
500 if (!fsg_is_set(fsg->common))
503 ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
506 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
508 switch (ctrl->bRequest) {
510 case US_BULK_RESET_REQUEST:
511 if (ctrl->bRequestType !=
512 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
514 if (w_index != fsg->interface_number || w_value != 0 ||
519 * Raise an exception to stop the current operation
520 * and reinitialize our state.
522 DBG(fsg, "bulk reset request\n");
523 raise_exception(fsg->common, FSG_STATE_RESET);
524 return DELAYED_STATUS;
526 case US_BULK_GET_MAX_LUN:
527 if (ctrl->bRequestType !=
528 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
530 if (w_index != fsg->interface_number || w_value != 0 ||
533 VDBG(fsg, "get max LUN\n");
534 *(u8 *)req->buf = fsg->common->nluns - 1;
536 /* Respond with data/status */
537 req->length = min((u16)1, w_length);
538 return ep0_queue(fsg->common);
542 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
543 ctrl->bRequestType, ctrl->bRequest,
544 le16_to_cpu(ctrl->wValue), w_index, w_length);
549 /*-------------------------------------------------------------------------*/
551 /* All the following routines run in process context */
553 /* Use this for bulk or interrupt transfers, not ep0 */
554 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
555 struct usb_request *req, int *pbusy,
556 enum fsg_buffer_state *state)
560 if (ep == fsg->bulk_in)
561 dump_msg(fsg, "bulk-in", req->buf, req->length);
563 spin_lock_irq(&fsg->common->lock);
565 *state = BUF_STATE_BUSY;
566 spin_unlock_irq(&fsg->common->lock);
567 rc = usb_ep_queue(ep, req, GFP_KERNEL);
570 *state = BUF_STATE_EMPTY;
572 /* We can't do much more than wait for a reset */
575 * Note: currently the net2280 driver fails zero-length
576 * submissions if DMA is enabled.
578 if (rc != -ESHUTDOWN &&
579 !(rc == -EOPNOTSUPP && req->length == 0))
580 WARNING(fsg, "error in submission: %s --> %d\n",
585 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
587 if (!fsg_is_set(common))
589 start_transfer(common->fsg, common->fsg->bulk_in,
590 bh->inreq, &bh->inreq_busy, &bh->state);
594 static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
596 if (!fsg_is_set(common))
598 start_transfer(common->fsg, common->fsg->bulk_out,
599 bh->outreq, &bh->outreq_busy, &bh->state);
603 static int sleep_thread(struct fsg_common *common)
607 /* Wait until a signal arrives or we are woken up */
610 set_current_state(TASK_INTERRUPTIBLE);
611 if (signal_pending(current)) {
615 if (common->thread_wakeup_needed)
619 __set_current_state(TASK_RUNNING);
620 common->thread_wakeup_needed = 0;
621 smp_rmb(); /* ensure the latest bh->state is visible */
626 /*-------------------------------------------------------------------------*/
628 static int do_read(struct fsg_common *common)
630 struct fsg_lun *curlun = common->curlun;
632 struct fsg_buffhd *bh;
635 loff_t file_offset, file_offset_tmp;
640 * Get the starting Logical Block Address and check that it's
643 if (common->cmnd[0] == READ_6)
644 lba = get_unaligned_be24(&common->cmnd[1]);
646 lba = get_unaligned_be32(&common->cmnd[2]);
649 * We allow DPO (Disable Page Out = don't save data in the
650 * cache) and FUA (Force Unit Access = don't read from the
651 * cache), but we don't implement them.
653 if ((common->cmnd[1] & ~0x18) != 0) {
654 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
658 if (lba >= curlun->num_sectors) {
659 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
662 file_offset = ((loff_t) lba) << curlun->blkbits;
664 /* Carry out the file reads */
665 amount_left = common->data_size_from_cmnd;
666 if (unlikely(amount_left == 0))
667 return -EIO; /* No default reply */
671 * Figure out how much we need to read:
672 * Try to read the remaining amount.
673 * But don't read more than the buffer size.
674 * And don't try to read past the end of the file.
676 amount = min(amount_left, FSG_BUFLEN);
677 amount = min((loff_t)amount,
678 curlun->file_length - file_offset);
680 /* Wait for the next buffer to become available */
681 bh = common->next_buffhd_to_fill;
682 while (bh->state != BUF_STATE_EMPTY) {
683 rc = sleep_thread(common);
689 * If we were asked to read past the end of file,
690 * end with an empty buffer.
694 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
695 curlun->sense_data_info =
696 file_offset >> curlun->blkbits;
697 curlun->info_valid = 1;
698 bh->inreq->length = 0;
699 bh->state = BUF_STATE_FULL;
703 /* Perform the read */
704 file_offset_tmp = file_offset;
705 nread = vfs_read(curlun->filp,
706 (char __user *)bh->buf,
707 amount, &file_offset_tmp);
708 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
709 (unsigned long long)file_offset, (int)nread);
710 if (signal_pending(current))
714 LDBG(curlun, "error in file read: %d\n", (int)nread);
716 } else if (nread < amount) {
717 LDBG(curlun, "partial file read: %d/%u\n",
719 nread = round_down(nread, curlun->blksize);
721 file_offset += nread;
722 amount_left -= nread;
723 common->residue -= nread;
726 * Except at the end of the transfer, nread will be
727 * equal to the buffer size, which is divisible by the
728 * bulk-in maxpacket size.
730 bh->inreq->length = nread;
731 bh->state = BUF_STATE_FULL;
733 /* If an error occurred, report it and its position */
734 if (nread < amount) {
735 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
736 curlun->sense_data_info =
737 file_offset >> curlun->blkbits;
738 curlun->info_valid = 1;
742 if (amount_left == 0)
743 break; /* No more left to read */
745 /* Send this buffer and go read some more */
747 if (!start_in_transfer(common, bh))
748 /* Don't know what to do if common->fsg is NULL */
750 common->next_buffhd_to_fill = bh->next;
753 return -EIO; /* No default reply */
757 /*-------------------------------------------------------------------------*/
759 static int do_write(struct fsg_common *common)
761 struct fsg_lun *curlun = common->curlun;
763 struct fsg_buffhd *bh;
765 u32 amount_left_to_req, amount_left_to_write;
766 loff_t usb_offset, file_offset, file_offset_tmp;
772 curlun->sense_data = SS_WRITE_PROTECTED;
775 spin_lock(&curlun->filp->f_lock);
776 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
777 spin_unlock(&curlun->filp->f_lock);
780 * Get the starting Logical Block Address and check that it's
783 if (common->cmnd[0] == WRITE_6)
784 lba = get_unaligned_be24(&common->cmnd[1]);
786 lba = get_unaligned_be32(&common->cmnd[2]);
789 * We allow DPO (Disable Page Out = don't save data in the
790 * cache) and FUA (Force Unit Access = write directly to the
791 * medium). We don't implement DPO; we implement FUA by
792 * performing synchronous output.
794 if (common->cmnd[1] & ~0x18) {
795 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
798 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
799 spin_lock(&curlun->filp->f_lock);
800 curlun->filp->f_flags |= O_SYNC;
801 spin_unlock(&curlun->filp->f_lock);
804 if (lba >= curlun->num_sectors) {
805 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
809 /* Carry out the file writes */
811 file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
812 amount_left_to_req = common->data_size_from_cmnd;
813 amount_left_to_write = common->data_size_from_cmnd;
815 while (amount_left_to_write > 0) {
817 /* Queue a request for more data from the host */
818 bh = common->next_buffhd_to_fill;
819 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
822 * Figure out how much we want to get:
823 * Try to get the remaining amount,
824 * but not more than the buffer size.
826 amount = min(amount_left_to_req, FSG_BUFLEN);
828 /* Beyond the end of the backing file? */
829 if (usb_offset >= curlun->file_length) {
832 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
833 curlun->sense_data_info =
834 usb_offset >> curlun->blkbits;
835 curlun->info_valid = 1;
839 /* Get the next buffer */
840 usb_offset += amount;
841 common->usb_amount_left -= amount;
842 amount_left_to_req -= amount;
843 if (amount_left_to_req == 0)
847 * Except at the end of the transfer, amount will be
848 * equal to the buffer size, which is divisible by
849 * the bulk-out maxpacket size.
851 set_bulk_out_req_length(common, bh, amount);
852 if (!start_out_transfer(common, bh))
853 /* Dunno what to do if common->fsg is NULL */
855 common->next_buffhd_to_fill = bh->next;
859 /* Write the received data to the backing file */
860 bh = common->next_buffhd_to_drain;
861 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
862 break; /* We stopped early */
863 if (bh->state == BUF_STATE_FULL) {
865 common->next_buffhd_to_drain = bh->next;
866 bh->state = BUF_STATE_EMPTY;
868 /* Did something go wrong with the transfer? */
869 if (bh->outreq->status != 0) {
870 curlun->sense_data = SS_COMMUNICATION_FAILURE;
871 curlun->sense_data_info =
872 file_offset >> curlun->blkbits;
873 curlun->info_valid = 1;
877 amount = bh->outreq->actual;
878 if (curlun->file_length - file_offset < amount) {
880 "write %u @ %llu beyond end %llu\n",
881 amount, (unsigned long long)file_offset,
882 (unsigned long long)curlun->file_length);
883 amount = curlun->file_length - file_offset;
886 /* Don't accept excess data. The spec doesn't say
887 * what to do in this case. We'll ignore the error.
889 amount = min(amount, bh->bulk_out_intended_length);
891 /* Don't write a partial block */
892 amount = round_down(amount, curlun->blksize);
896 /* Perform the write */
897 file_offset_tmp = file_offset;
898 nwritten = vfs_write(curlun->filp,
899 (char __user *)bh->buf,
900 amount, &file_offset_tmp);
901 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
902 (unsigned long long)file_offset, (int)nwritten);
903 if (signal_pending(current))
904 return -EINTR; /* Interrupted! */
907 LDBG(curlun, "error in file write: %d\n",
910 } else if (nwritten < amount) {
911 LDBG(curlun, "partial file write: %d/%u\n",
912 (int)nwritten, amount);
913 nwritten = round_down(nwritten, curlun->blksize);
915 file_offset += nwritten;
916 amount_left_to_write -= nwritten;
917 common->residue -= nwritten;
919 /* If an error occurred, report it and its position */
920 if (nwritten < amount) {
921 curlun->sense_data = SS_WRITE_ERROR;
922 curlun->sense_data_info =
923 file_offset >> curlun->blkbits;
924 curlun->info_valid = 1;
929 /* Did the host decide to stop early? */
930 if (bh->outreq->actual < bh->bulk_out_intended_length) {
931 common->short_packet_received = 1;
937 /* Wait for something to happen */
938 rc = sleep_thread(common);
943 return -EIO; /* No default reply */
947 /*-------------------------------------------------------------------------*/
949 static int do_synchronize_cache(struct fsg_common *common)
951 struct fsg_lun *curlun = common->curlun;
954 /* We ignore the requested LBA and write out all file's
955 * dirty data buffers. */
956 rc = fsg_lun_fsync_sub(curlun);
958 curlun->sense_data = SS_WRITE_ERROR;
963 /*-------------------------------------------------------------------------*/
965 static void invalidate_sub(struct fsg_lun *curlun)
967 struct file *filp = curlun->filp;
968 struct inode *inode = file_inode(filp);
971 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
972 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
975 static int do_verify(struct fsg_common *common)
977 struct fsg_lun *curlun = common->curlun;
979 u32 verification_length;
980 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
981 loff_t file_offset, file_offset_tmp;
987 * Get the starting Logical Block Address and check that it's
990 lba = get_unaligned_be32(&common->cmnd[2]);
991 if (lba >= curlun->num_sectors) {
992 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
997 * We allow DPO (Disable Page Out = don't save data in the
998 * cache) but we don't implement it.
1000 if (common->cmnd[1] & ~0x10) {
1001 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1005 verification_length = get_unaligned_be16(&common->cmnd[7]);
1006 if (unlikely(verification_length == 0))
1007 return -EIO; /* No default reply */
1009 /* Prepare to carry out the file verify */
1010 amount_left = verification_length << curlun->blkbits;
1011 file_offset = ((loff_t) lba) << curlun->blkbits;
1013 /* Write out all the dirty buffers before invalidating them */
1014 fsg_lun_fsync_sub(curlun);
1015 if (signal_pending(current))
1018 invalidate_sub(curlun);
1019 if (signal_pending(current))
1022 /* Just try to read the requested blocks */
1023 while (amount_left > 0) {
1025 * Figure out how much we need to read:
1026 * Try to read the remaining amount, but not more than
1028 * And don't try to read past the end of the file.
1030 amount = min(amount_left, FSG_BUFLEN);
1031 amount = min((loff_t)amount,
1032 curlun->file_length - file_offset);
1034 curlun->sense_data =
1035 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1036 curlun->sense_data_info =
1037 file_offset >> curlun->blkbits;
1038 curlun->info_valid = 1;
1042 /* Perform the read */
1043 file_offset_tmp = file_offset;
1044 nread = vfs_read(curlun->filp,
1045 (char __user *) bh->buf,
1046 amount, &file_offset_tmp);
1047 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1048 (unsigned long long) file_offset,
1050 if (signal_pending(current))
1054 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1056 } else if (nread < amount) {
1057 LDBG(curlun, "partial file verify: %d/%u\n",
1058 (int)nread, amount);
1059 nread = round_down(nread, curlun->blksize);
1062 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1063 curlun->sense_data_info =
1064 file_offset >> curlun->blkbits;
1065 curlun->info_valid = 1;
1068 file_offset += nread;
1069 amount_left -= nread;
1075 /*-------------------------------------------------------------------------*/
1077 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1079 struct fsg_lun *curlun = common->curlun;
1080 u8 *buf = (u8 *) bh->buf;
1082 if (!curlun) { /* Unsupported LUNs are okay */
1083 common->bad_lun_okay = 1;
1085 buf[0] = 0x7f; /* Unsupported, no device-type */
1086 buf[4] = 31; /* Additional length */
1090 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1091 buf[1] = curlun->removable ? 0x80 : 0;
1092 buf[2] = 2; /* ANSI SCSI level 2 */
1093 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1094 buf[4] = 31; /* Additional length */
1095 buf[5] = 0; /* No special options */
1098 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1102 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1104 struct fsg_lun *curlun = common->curlun;
1105 u8 *buf = (u8 *) bh->buf;
1110 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1112 * If a REQUEST SENSE command is received from an initiator
1113 * with a pending unit attention condition (before the target
1114 * generates the contingent allegiance condition), then the
1115 * target shall either:
1116 * a) report any pending sense data and preserve the unit
1117 * attention condition on the logical unit, or,
1118 * b) report the unit attention condition, may discard any
1119 * pending sense data, and clear the unit attention
1120 * condition on the logical unit for that initiator.
1122 * FSG normally uses option a); enable this code to use option b).
1125 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1126 curlun->sense_data = curlun->unit_attention_data;
1127 curlun->unit_attention_data = SS_NO_SENSE;
1131 if (!curlun) { /* Unsupported LUNs are okay */
1132 common->bad_lun_okay = 1;
1133 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1137 sd = curlun->sense_data;
1138 sdinfo = curlun->sense_data_info;
1139 valid = curlun->info_valid << 7;
1140 curlun->sense_data = SS_NO_SENSE;
1141 curlun->sense_data_info = 0;
1142 curlun->info_valid = 0;
1146 buf[0] = valid | 0x70; /* Valid, current error */
1148 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1149 buf[7] = 18 - 8; /* Additional sense length */
1155 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1157 struct fsg_lun *curlun = common->curlun;
1158 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1159 int pmi = common->cmnd[8];
1160 u8 *buf = (u8 *)bh->buf;
1162 /* Check the PMI and LBA fields */
1163 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1164 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1168 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1169 /* Max logical block */
1170 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1174 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1176 struct fsg_lun *curlun = common->curlun;
1177 int msf = common->cmnd[1] & 0x02;
1178 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1179 u8 *buf = (u8 *)bh->buf;
1181 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1182 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1185 if (lba >= curlun->num_sectors) {
1186 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1191 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1192 store_cdrom_address(&buf[4], msf, lba);
1196 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1198 struct fsg_lun *curlun = common->curlun;
1199 int msf = common->cmnd[1] & 0x02;
1200 int start_track = common->cmnd[6];
1201 u8 *buf = (u8 *)bh->buf;
1203 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1205 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1210 buf[1] = (20-2); /* TOC data length */
1211 buf[2] = 1; /* First track number */
1212 buf[3] = 1; /* Last track number */
1213 buf[5] = 0x16; /* Data track, copying allowed */
1214 buf[6] = 0x01; /* Only track is number 1 */
1215 store_cdrom_address(&buf[8], msf, 0);
1217 buf[13] = 0x16; /* Lead-out track is data */
1218 buf[14] = 0xAA; /* Lead-out track number */
1219 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1223 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1225 struct fsg_lun *curlun = common->curlun;
1226 int mscmnd = common->cmnd[0];
1227 u8 *buf = (u8 *) bh->buf;
1230 int changeable_values, all_pages;
1234 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1235 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1238 pc = common->cmnd[2] >> 6;
1239 page_code = common->cmnd[2] & 0x3f;
1241 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1244 changeable_values = (pc == 1);
1245 all_pages = (page_code == 0x3f);
1248 * Write the mode parameter header. Fixed values are: default
1249 * medium type, no cache control (DPOFUA), and no block descriptors.
1250 * The only variable value is the WriteProtect bit. We will fill in
1251 * the mode data length later.
1254 if (mscmnd == MODE_SENSE) {
1255 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1258 } else { /* MODE_SENSE_10 */
1259 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1261 limit = 65535; /* Should really be FSG_BUFLEN */
1264 /* No block descriptors */
1267 * The mode pages, in numerical order. The only page we support
1268 * is the Caching page.
1270 if (page_code == 0x08 || all_pages) {
1272 buf[0] = 0x08; /* Page code */
1273 buf[1] = 10; /* Page length */
1274 memset(buf+2, 0, 10); /* None of the fields are changeable */
1276 if (!changeable_values) {
1277 buf[2] = 0x04; /* Write cache enable, */
1278 /* Read cache not disabled */
1279 /* No cache retention priorities */
1280 put_unaligned_be16(0xffff, &buf[4]);
1281 /* Don't disable prefetch */
1282 /* Minimum prefetch = 0 */
1283 put_unaligned_be16(0xffff, &buf[8]);
1284 /* Maximum prefetch */
1285 put_unaligned_be16(0xffff, &buf[10]);
1286 /* Maximum prefetch ceiling */
1292 * Check that a valid page was requested and the mode data length
1296 if (!valid_page || len > limit) {
1297 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1301 /* Store the mode data length */
1302 if (mscmnd == MODE_SENSE)
1305 put_unaligned_be16(len - 2, buf0);
1309 static int do_start_stop(struct fsg_common *common)
1311 struct fsg_lun *curlun = common->curlun;
1316 } else if (!curlun->removable) {
1317 curlun->sense_data = SS_INVALID_COMMAND;
1319 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1320 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1321 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1325 loej = common->cmnd[4] & 0x02;
1326 start = common->cmnd[4] & 0x01;
1329 * Our emulation doesn't support mounting; the medium is
1330 * available for use as soon as it is loaded.
1333 if (!fsg_lun_is_open(curlun)) {
1334 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1340 /* Are we allowed to unload the media? */
1341 if (curlun->prevent_medium_removal) {
1342 LDBG(curlun, "unload attempt prevented\n");
1343 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1350 up_read(&common->filesem);
1351 down_write(&common->filesem);
1352 fsg_lun_close(curlun);
1353 up_write(&common->filesem);
1354 down_read(&common->filesem);
1359 static int do_prevent_allow(struct fsg_common *common)
1361 struct fsg_lun *curlun = common->curlun;
1364 if (!common->curlun) {
1366 } else if (!common->curlun->removable) {
1367 common->curlun->sense_data = SS_INVALID_COMMAND;
1371 prevent = common->cmnd[4] & 0x01;
1372 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1373 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1377 if (curlun->prevent_medium_removal && !prevent)
1378 fsg_lun_fsync_sub(curlun);
1379 curlun->prevent_medium_removal = prevent;
1383 static int do_read_format_capacities(struct fsg_common *common,
1384 struct fsg_buffhd *bh)
1386 struct fsg_lun *curlun = common->curlun;
1387 u8 *buf = (u8 *) bh->buf;
1389 buf[0] = buf[1] = buf[2] = 0;
1390 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1393 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1394 /* Number of blocks */
1395 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1396 buf[4] = 0x02; /* Current capacity */
1400 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1402 struct fsg_lun *curlun = common->curlun;
1404 /* We don't support MODE SELECT */
1406 curlun->sense_data = SS_INVALID_COMMAND;
1411 /*-------------------------------------------------------------------------*/
1413 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1417 rc = fsg_set_halt(fsg, fsg->bulk_in);
1419 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1421 if (rc != -EAGAIN) {
1422 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1427 /* Wait for a short time and then try again */
1428 if (msleep_interruptible(100) != 0)
1430 rc = usb_ep_set_halt(fsg->bulk_in);
1435 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1439 DBG(fsg, "bulk-in set wedge\n");
1440 rc = usb_ep_set_wedge(fsg->bulk_in);
1442 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1444 if (rc != -EAGAIN) {
1445 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1450 /* Wait for a short time and then try again */
1451 if (msleep_interruptible(100) != 0)
1453 rc = usb_ep_set_wedge(fsg->bulk_in);
1458 static int throw_away_data(struct fsg_common *common)
1460 struct fsg_buffhd *bh;
1464 for (bh = common->next_buffhd_to_drain;
1465 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1466 bh = common->next_buffhd_to_drain) {
1468 /* Throw away the data in a filled buffer */
1469 if (bh->state == BUF_STATE_FULL) {
1471 bh->state = BUF_STATE_EMPTY;
1472 common->next_buffhd_to_drain = bh->next;
1474 /* A short packet or an error ends everything */
1475 if (bh->outreq->actual < bh->bulk_out_intended_length ||
1476 bh->outreq->status != 0) {
1477 raise_exception(common,
1478 FSG_STATE_ABORT_BULK_OUT);
1484 /* Try to submit another request if we need one */
1485 bh = common->next_buffhd_to_fill;
1486 if (bh->state == BUF_STATE_EMPTY
1487 && common->usb_amount_left > 0) {
1488 amount = min(common->usb_amount_left, FSG_BUFLEN);
1491 * Except at the end of the transfer, amount will be
1492 * equal to the buffer size, which is divisible by
1493 * the bulk-out maxpacket size.
1495 set_bulk_out_req_length(common, bh, amount);
1496 if (!start_out_transfer(common, bh))
1497 /* Dunno what to do if common->fsg is NULL */
1499 common->next_buffhd_to_fill = bh->next;
1500 common->usb_amount_left -= amount;
1504 /* Otherwise wait for something to happen */
1505 rc = sleep_thread(common);
1512 static int finish_reply(struct fsg_common *common)
1514 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1517 switch (common->data_dir) {
1519 break; /* Nothing to send */
1522 * If we don't know whether the host wants to read or write,
1523 * this must be CB or CBI with an unknown command. We mustn't
1524 * try to send or receive any data. So stall both bulk pipes
1525 * if we can and wait for a reset.
1527 case DATA_DIR_UNKNOWN:
1528 if (!common->can_stall) {
1530 } else if (fsg_is_set(common)) {
1531 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1532 rc = halt_bulk_in_endpoint(common->fsg);
1534 /* Don't know what to do if common->fsg is NULL */
1539 /* All but the last buffer of data must have already been sent */
1540 case DATA_DIR_TO_HOST:
1541 if (common->data_size == 0) {
1542 /* Nothing to send */
1544 /* Don't know what to do if common->fsg is NULL */
1545 } else if (!fsg_is_set(common)) {
1548 /* If there's no residue, simply send the last buffer */
1549 } else if (common->residue == 0) {
1550 bh->inreq->zero = 0;
1551 if (!start_in_transfer(common, bh))
1553 common->next_buffhd_to_fill = bh->next;
1556 * For Bulk-only, mark the end of the data with a short
1557 * packet. If we are allowed to stall, halt the bulk-in
1558 * endpoint. (Note: This violates the Bulk-Only Transport
1559 * specification, which requires us to pad the data if we
1560 * don't halt the endpoint. Presumably nobody will mind.)
1563 bh->inreq->zero = 1;
1564 if (!start_in_transfer(common, bh))
1566 common->next_buffhd_to_fill = bh->next;
1567 if (common->can_stall)
1568 rc = halt_bulk_in_endpoint(common->fsg);
1573 * We have processed all we want from the data the host has sent.
1574 * There may still be outstanding bulk-out requests.
1576 case DATA_DIR_FROM_HOST:
1577 if (common->residue == 0) {
1578 /* Nothing to receive */
1580 /* Did the host stop sending unexpectedly early? */
1581 } else if (common->short_packet_received) {
1582 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1586 * We haven't processed all the incoming data. Even though
1587 * we may be allowed to stall, doing so would cause a race.
1588 * The controller may already have ACK'ed all the remaining
1589 * bulk-out packets, in which case the host wouldn't see a
1590 * STALL. Not realizing the endpoint was halted, it wouldn't
1591 * clear the halt -- leading to problems later on.
1594 } else if (common->can_stall) {
1595 if (fsg_is_set(common))
1596 fsg_set_halt(common->fsg,
1597 common->fsg->bulk_out);
1598 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1603 * We can't stall. Read in the excess data and throw it
1607 rc = throw_away_data(common);
1614 static int send_status(struct fsg_common *common)
1616 struct fsg_lun *curlun = common->curlun;
1617 struct fsg_buffhd *bh;
1618 struct bulk_cs_wrap *csw;
1620 u8 status = US_BULK_STAT_OK;
1623 /* Wait for the next buffer to become available */
1624 bh = common->next_buffhd_to_fill;
1625 while (bh->state != BUF_STATE_EMPTY) {
1626 rc = sleep_thread(common);
1632 sd = curlun->sense_data;
1633 sdinfo = curlun->sense_data_info;
1634 } else if (common->bad_lun_okay)
1637 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1639 if (common->phase_error) {
1640 DBG(common, "sending phase-error status\n");
1641 status = US_BULK_STAT_PHASE;
1642 sd = SS_INVALID_COMMAND;
1643 } else if (sd != SS_NO_SENSE) {
1644 DBG(common, "sending command-failure status\n");
1645 status = US_BULK_STAT_FAIL;
1646 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1648 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1651 /* Store and send the Bulk-only CSW */
1652 csw = (void *)bh->buf;
1654 csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
1655 csw->Tag = common->tag;
1656 csw->Residue = cpu_to_le32(common->residue);
1657 csw->Status = status;
1659 bh->inreq->length = US_BULK_CS_WRAP_LEN;
1660 bh->inreq->zero = 0;
1661 if (!start_in_transfer(common, bh))
1662 /* Don't know what to do if common->fsg is NULL */
1665 common->next_buffhd_to_fill = bh->next;
1670 /*-------------------------------------------------------------------------*/
1673 * Check whether the command is properly formed and whether its data size
1674 * and direction agree with the values we already have.
1676 static int check_command(struct fsg_common *common, int cmnd_size,
1677 enum data_direction data_dir, unsigned int mask,
1678 int needs_medium, const char *name)
1681 unsigned int lun = common->cmnd[1] >> 5;
1682 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1684 struct fsg_lun *curlun;
1687 if (common->data_dir != DATA_DIR_UNKNOWN)
1688 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1690 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1691 name, cmnd_size, dirletter[(int) data_dir],
1692 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1695 * We can't reply at all until we know the correct data direction
1698 if (common->data_size_from_cmnd == 0)
1699 data_dir = DATA_DIR_NONE;
1700 if (common->data_size < common->data_size_from_cmnd) {
1702 * Host data size < Device data size is a phase error.
1703 * Carry out the command, but only transfer as much as
1706 common->data_size_from_cmnd = common->data_size;
1707 common->phase_error = 1;
1709 common->residue = common->data_size;
1710 common->usb_amount_left = common->data_size;
1712 /* Conflicting data directions is a phase error */
1713 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1714 common->phase_error = 1;
1718 /* Verify the length of the command itself */
1719 if (cmnd_size != common->cmnd_size) {
1722 * Special case workaround: There are plenty of buggy SCSI
1723 * implementations. Many have issues with cbw->Length
1724 * field passing a wrong command size. For those cases we
1725 * always try to work around the problem by using the length
1726 * sent by the host side provided it is at least as large
1727 * as the correct command length.
1728 * Examples of such cases would be MS-Windows, which issues
1729 * REQUEST SENSE with cbw->Length == 12 where it should
1730 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1731 * REQUEST SENSE with cbw->Length == 10 where it should
1734 if (cmnd_size <= common->cmnd_size) {
1735 DBG(common, "%s is buggy! Expected length %d "
1736 "but we got %d\n", name,
1737 cmnd_size, common->cmnd_size);
1738 cmnd_size = common->cmnd_size;
1740 common->phase_error = 1;
1745 /* Check that the LUN values are consistent */
1746 if (common->lun != lun)
1747 DBG(common, "using LUN %u from CBW, not LUN %u from CDB\n",
1751 curlun = common->curlun;
1753 if (common->cmnd[0] != REQUEST_SENSE) {
1754 curlun->sense_data = SS_NO_SENSE;
1755 curlun->sense_data_info = 0;
1756 curlun->info_valid = 0;
1759 common->bad_lun_okay = 0;
1762 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1763 * to use unsupported LUNs; all others may not.
1765 if (common->cmnd[0] != INQUIRY &&
1766 common->cmnd[0] != REQUEST_SENSE) {
1767 DBG(common, "unsupported LUN %u\n", common->lun);
1773 * If a unit attention condition exists, only INQUIRY and
1774 * REQUEST SENSE commands are allowed; anything else must fail.
1776 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1777 common->cmnd[0] != INQUIRY &&
1778 common->cmnd[0] != REQUEST_SENSE) {
1779 curlun->sense_data = curlun->unit_attention_data;
1780 curlun->unit_attention_data = SS_NO_SENSE;
1784 /* Check that only command bytes listed in the mask are non-zero */
1785 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1786 for (i = 1; i < cmnd_size; ++i) {
1787 if (common->cmnd[i] && !(mask & (1 << i))) {
1789 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1794 /* If the medium isn't mounted and the command needs to access
1795 * it, return an error. */
1796 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1797 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1804 /* wrapper of check_command for data size in blocks handling */
1805 static int check_command_size_in_blocks(struct fsg_common *common,
1806 int cmnd_size, enum data_direction data_dir,
1807 unsigned int mask, int needs_medium, const char *name)
1810 common->data_size_from_cmnd <<= common->curlun->blkbits;
1811 return check_command(common, cmnd_size, data_dir,
1812 mask, needs_medium, name);
1815 static int do_scsi_command(struct fsg_common *common)
1817 struct fsg_buffhd *bh;
1819 int reply = -EINVAL;
1821 static char unknown[16];
1825 /* Wait for the next buffer to become available for data or status */
1826 bh = common->next_buffhd_to_fill;
1827 common->next_buffhd_to_drain = bh;
1828 while (bh->state != BUF_STATE_EMPTY) {
1829 rc = sleep_thread(common);
1833 common->phase_error = 0;
1834 common->short_packet_received = 0;
1836 down_read(&common->filesem); /* We're using the backing file */
1837 switch (common->cmnd[0]) {
1840 common->data_size_from_cmnd = common->cmnd[4];
1841 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1845 reply = do_inquiry(common, bh);
1849 common->data_size_from_cmnd = common->cmnd[4];
1850 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1854 reply = do_mode_select(common, bh);
1857 case MODE_SELECT_10:
1858 common->data_size_from_cmnd =
1859 get_unaligned_be16(&common->cmnd[7]);
1860 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1864 reply = do_mode_select(common, bh);
1868 common->data_size_from_cmnd = common->cmnd[4];
1869 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1870 (1<<1) | (1<<2) | (1<<4), 0,
1873 reply = do_mode_sense(common, bh);
1877 common->data_size_from_cmnd =
1878 get_unaligned_be16(&common->cmnd[7]);
1879 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1880 (1<<1) | (1<<2) | (3<<7), 0,
1883 reply = do_mode_sense(common, bh);
1886 case ALLOW_MEDIUM_REMOVAL:
1887 common->data_size_from_cmnd = 0;
1888 reply = check_command(common, 6, DATA_DIR_NONE,
1890 "PREVENT-ALLOW MEDIUM REMOVAL");
1892 reply = do_prevent_allow(common);
1896 i = common->cmnd[4];
1897 common->data_size_from_cmnd = (i == 0) ? 256 : i;
1898 reply = check_command_size_in_blocks(common, 6,
1903 reply = do_read(common);
1907 common->data_size_from_cmnd =
1908 get_unaligned_be16(&common->cmnd[7]);
1909 reply = check_command_size_in_blocks(common, 10,
1911 (1<<1) | (0xf<<2) | (3<<7), 1,
1914 reply = do_read(common);
1918 common->data_size_from_cmnd =
1919 get_unaligned_be32(&common->cmnd[6]);
1920 reply = check_command_size_in_blocks(common, 12,
1922 (1<<1) | (0xf<<2) | (0xf<<6), 1,
1925 reply = do_read(common);
1929 common->data_size_from_cmnd = 8;
1930 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1931 (0xf<<2) | (1<<8), 1,
1934 reply = do_read_capacity(common, bh);
1938 if (!common->curlun || !common->curlun->cdrom)
1940 common->data_size_from_cmnd =
1941 get_unaligned_be16(&common->cmnd[7]);
1942 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1943 (3<<7) | (0x1f<<1), 1,
1946 reply = do_read_header(common, bh);
1950 if (!common->curlun || !common->curlun->cdrom)
1952 common->data_size_from_cmnd =
1953 get_unaligned_be16(&common->cmnd[7]);
1954 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1958 reply = do_read_toc(common, bh);
1961 case READ_FORMAT_CAPACITIES:
1962 common->data_size_from_cmnd =
1963 get_unaligned_be16(&common->cmnd[7]);
1964 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1966 "READ FORMAT CAPACITIES");
1968 reply = do_read_format_capacities(common, bh);
1972 common->data_size_from_cmnd = common->cmnd[4];
1973 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1977 reply = do_request_sense(common, bh);
1981 common->data_size_from_cmnd = 0;
1982 reply = check_command(common, 6, DATA_DIR_NONE,
1986 reply = do_start_stop(common);
1989 case SYNCHRONIZE_CACHE:
1990 common->data_size_from_cmnd = 0;
1991 reply = check_command(common, 10, DATA_DIR_NONE,
1992 (0xf<<2) | (3<<7), 1,
1993 "SYNCHRONIZE CACHE");
1995 reply = do_synchronize_cache(common);
1998 case TEST_UNIT_READY:
1999 common->data_size_from_cmnd = 0;
2000 reply = check_command(common, 6, DATA_DIR_NONE,
2006 * Although optional, this command is used by MS-Windows. We
2007 * support a minimal version: BytChk must be 0.
2010 common->data_size_from_cmnd = 0;
2011 reply = check_command(common, 10, DATA_DIR_NONE,
2012 (1<<1) | (0xf<<2) | (3<<7), 1,
2015 reply = do_verify(common);
2019 i = common->cmnd[4];
2020 common->data_size_from_cmnd = (i == 0) ? 256 : i;
2021 reply = check_command_size_in_blocks(common, 6,
2026 reply = do_write(common);
2030 common->data_size_from_cmnd =
2031 get_unaligned_be16(&common->cmnd[7]);
2032 reply = check_command_size_in_blocks(common, 10,
2034 (1<<1) | (0xf<<2) | (3<<7), 1,
2037 reply = do_write(common);
2041 common->data_size_from_cmnd =
2042 get_unaligned_be32(&common->cmnd[6]);
2043 reply = check_command_size_in_blocks(common, 12,
2045 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2048 reply = do_write(common);
2052 * Some mandatory commands that we recognize but don't implement.
2053 * They don't mean much in this setting. It's left as an exercise
2054 * for anyone interested to implement RESERVE and RELEASE in terms
2060 case SEND_DIAGNOSTIC:
2065 common->data_size_from_cmnd = 0;
2066 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2067 reply = check_command(common, common->cmnd_size,
2068 DATA_DIR_UNKNOWN, ~0, 0, unknown);
2070 common->curlun->sense_data = SS_INVALID_COMMAND;
2075 up_read(&common->filesem);
2077 if (reply == -EINTR || signal_pending(current))
2080 /* Set up the single reply buffer for finish_reply() */
2081 if (reply == -EINVAL)
2082 reply = 0; /* Error reply length */
2083 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2084 reply = min((u32)reply, common->data_size_from_cmnd);
2085 bh->inreq->length = reply;
2086 bh->state = BUF_STATE_FULL;
2087 common->residue -= reply;
2088 } /* Otherwise it's already set */
2094 /*-------------------------------------------------------------------------*/
2096 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2098 struct usb_request *req = bh->outreq;
2099 struct bulk_cb_wrap *cbw = req->buf;
2100 struct fsg_common *common = fsg->common;
2102 /* Was this a real packet? Should it be ignored? */
2103 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2106 /* Is the CBW valid? */
2107 if (req->actual != US_BULK_CB_WRAP_LEN ||
2108 cbw->Signature != cpu_to_le32(
2110 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2112 le32_to_cpu(cbw->Signature));
2115 * The Bulk-only spec says we MUST stall the IN endpoint
2116 * (6.6.1), so it's unavoidable. It also says we must
2117 * retain this state until the next reset, but there's
2118 * no way to tell the controller driver it should ignore
2119 * Clear-Feature(HALT) requests.
2121 * We aren't required to halt the OUT endpoint; instead
2122 * we can simply accept and discard any data received
2123 * until the next reset.
2125 wedge_bulk_in_endpoint(fsg);
2126 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2130 /* Is the CBW meaningful? */
2131 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~US_BULK_FLAG_IN ||
2132 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2133 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2135 cbw->Lun, cbw->Flags, cbw->Length);
2138 * We can do anything we want here, so let's stall the
2139 * bulk pipes if we are allowed to.
2141 if (common->can_stall) {
2142 fsg_set_halt(fsg, fsg->bulk_out);
2143 halt_bulk_in_endpoint(fsg);
2148 /* Save the command for later */
2149 common->cmnd_size = cbw->Length;
2150 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2151 if (cbw->Flags & US_BULK_FLAG_IN)
2152 common->data_dir = DATA_DIR_TO_HOST;
2154 common->data_dir = DATA_DIR_FROM_HOST;
2155 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2156 if (common->data_size == 0)
2157 common->data_dir = DATA_DIR_NONE;
2158 common->lun = cbw->Lun;
2159 if (common->lun < common->nluns)
2160 common->curlun = common->luns[common->lun];
2162 common->curlun = NULL;
2163 common->tag = cbw->Tag;
2167 static int get_next_command(struct fsg_common *common)
2169 struct fsg_buffhd *bh;
2172 /* Wait for the next buffer to become available */
2173 bh = common->next_buffhd_to_fill;
2174 while (bh->state != BUF_STATE_EMPTY) {
2175 rc = sleep_thread(common);
2180 /* Queue a request to read a Bulk-only CBW */
2181 set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
2182 if (!start_out_transfer(common, bh))
2183 /* Don't know what to do if common->fsg is NULL */
2187 * We will drain the buffer in software, which means we
2188 * can reuse it for the next filling. No need to advance
2189 * next_buffhd_to_fill.
2192 /* Wait for the CBW to arrive */
2193 while (bh->state != BUF_STATE_FULL) {
2194 rc = sleep_thread(common);
2199 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2200 bh->state = BUF_STATE_EMPTY;
2206 /*-------------------------------------------------------------------------*/
2208 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2209 struct usb_request **preq)
2211 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2214 ERROR(common, "can't allocate request for %s\n", ep->name);
2218 /* Reset interface setting and re-init endpoint state (toggle etc). */
2219 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2221 struct fsg_dev *fsg;
2224 if (common->running)
2225 DBG(common, "reset interface\n");
2228 /* Deallocate the requests */
2232 for (i = 0; i < common->fsg_num_buffers; ++i) {
2233 struct fsg_buffhd *bh = &common->buffhds[i];
2236 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2240 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2245 /* Disable the endpoints */
2246 if (fsg->bulk_in_enabled) {
2247 usb_ep_disable(fsg->bulk_in);
2248 fsg->bulk_in->driver_data = NULL;
2249 fsg->bulk_in_enabled = 0;
2251 if (fsg->bulk_out_enabled) {
2252 usb_ep_disable(fsg->bulk_out);
2253 fsg->bulk_out->driver_data = NULL;
2254 fsg->bulk_out_enabled = 0;
2258 wake_up(&common->fsg_wait);
2261 common->running = 0;
2265 common->fsg = new_fsg;
2268 /* Enable the endpoints */
2269 rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
2272 rc = usb_ep_enable(fsg->bulk_in);
2275 fsg->bulk_in->driver_data = common;
2276 fsg->bulk_in_enabled = 1;
2278 rc = config_ep_by_speed(common->gadget, &(fsg->function),
2282 rc = usb_ep_enable(fsg->bulk_out);
2285 fsg->bulk_out->driver_data = common;
2286 fsg->bulk_out_enabled = 1;
2287 common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc);
2288 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2290 /* Allocate the requests */
2291 for (i = 0; i < common->fsg_num_buffers; ++i) {
2292 struct fsg_buffhd *bh = &common->buffhds[i];
2294 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2297 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2300 bh->inreq->buf = bh->outreq->buf = bh->buf;
2301 bh->inreq->context = bh->outreq->context = bh;
2302 bh->inreq->complete = bulk_in_complete;
2303 bh->outreq->complete = bulk_out_complete;
2306 common->running = 1;
2307 for (i = 0; i < common->nluns; ++i)
2308 if (common->luns[i])
2309 common->luns[i]->unit_attention_data =
2315 /****************************** ALT CONFIGS ******************************/
2317 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2319 struct fsg_dev *fsg = fsg_from_func(f);
2320 fsg->common->new_fsg = fsg;
2321 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2322 return USB_GADGET_DELAYED_STATUS;
2325 static void fsg_disable(struct usb_function *f)
2327 struct fsg_dev *fsg = fsg_from_func(f);
2328 fsg->common->new_fsg = NULL;
2329 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2333 /*-------------------------------------------------------------------------*/
2335 static void handle_exception(struct fsg_common *common)
2339 struct fsg_buffhd *bh;
2340 enum fsg_state old_state;
2341 struct fsg_lun *curlun;
2342 unsigned int exception_req_tag;
2345 * Clear the existing signals. Anything but SIGUSR1 is converted
2346 * into a high-priority EXIT exception.
2350 dequeue_signal_lock(current, ¤t->blocked, &info);
2353 if (sig != SIGUSR1) {
2354 if (common->state < FSG_STATE_EXIT)
2355 DBG(common, "Main thread exiting on signal\n");
2356 raise_exception(common, FSG_STATE_EXIT);
2360 /* Cancel all the pending transfers */
2361 if (likely(common->fsg)) {
2362 for (i = 0; i < common->fsg_num_buffers; ++i) {
2363 bh = &common->buffhds[i];
2365 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2366 if (bh->outreq_busy)
2367 usb_ep_dequeue(common->fsg->bulk_out,
2371 /* Wait until everything is idle */
2374 for (i = 0; i < common->fsg_num_buffers; ++i) {
2375 bh = &common->buffhds[i];
2376 num_active += bh->inreq_busy + bh->outreq_busy;
2378 if (num_active == 0)
2380 if (sleep_thread(common))
2384 /* Clear out the controller's fifos */
2385 if (common->fsg->bulk_in_enabled)
2386 usb_ep_fifo_flush(common->fsg->bulk_in);
2387 if (common->fsg->bulk_out_enabled)
2388 usb_ep_fifo_flush(common->fsg->bulk_out);
2392 * Reset the I/O buffer states and pointers, the SCSI
2393 * state, and the exception. Then invoke the handler.
2395 spin_lock_irq(&common->lock);
2397 for (i = 0; i < common->fsg_num_buffers; ++i) {
2398 bh = &common->buffhds[i];
2399 bh->state = BUF_STATE_EMPTY;
2401 common->next_buffhd_to_fill = &common->buffhds[0];
2402 common->next_buffhd_to_drain = &common->buffhds[0];
2403 exception_req_tag = common->exception_req_tag;
2404 old_state = common->state;
2406 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2407 common->state = FSG_STATE_STATUS_PHASE;
2409 for (i = 0; i < common->nluns; ++i) {
2410 curlun = common->luns[i];
2413 curlun->prevent_medium_removal = 0;
2414 curlun->sense_data = SS_NO_SENSE;
2415 curlun->unit_attention_data = SS_NO_SENSE;
2416 curlun->sense_data_info = 0;
2417 curlun->info_valid = 0;
2419 common->state = FSG_STATE_IDLE;
2421 spin_unlock_irq(&common->lock);
2423 /* Carry out any extra actions required for the exception */
2424 switch (old_state) {
2425 case FSG_STATE_ABORT_BULK_OUT:
2426 send_status(common);
2427 spin_lock_irq(&common->lock);
2428 if (common->state == FSG_STATE_STATUS_PHASE)
2429 common->state = FSG_STATE_IDLE;
2430 spin_unlock_irq(&common->lock);
2433 case FSG_STATE_RESET:
2435 * In case we were forced against our will to halt a
2436 * bulk endpoint, clear the halt now. (The SuperH UDC
2439 if (!fsg_is_set(common))
2441 if (test_and_clear_bit(IGNORE_BULK_OUT,
2442 &common->fsg->atomic_bitflags))
2443 usb_ep_clear_halt(common->fsg->bulk_in);
2445 if (common->ep0_req_tag == exception_req_tag)
2446 ep0_queue(common); /* Complete the status stage */
2449 * Technically this should go here, but it would only be
2450 * a waste of time. Ditto for the INTERFACE_CHANGE and
2451 * CONFIG_CHANGE cases.
2453 /* for (i = 0; i < common->nluns; ++i) */
2454 /* if (common->luns[i]) */
2455 /* common->luns[i]->unit_attention_data = */
2456 /* SS_RESET_OCCURRED; */
2459 case FSG_STATE_CONFIG_CHANGE:
2460 do_set_interface(common, common->new_fsg);
2461 if (common->new_fsg)
2462 usb_composite_setup_continue(common->cdev);
2465 case FSG_STATE_EXIT:
2466 case FSG_STATE_TERMINATED:
2467 do_set_interface(common, NULL); /* Free resources */
2468 spin_lock_irq(&common->lock);
2469 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2470 spin_unlock_irq(&common->lock);
2473 case FSG_STATE_INTERFACE_CHANGE:
2474 case FSG_STATE_DISCONNECT:
2475 case FSG_STATE_COMMAND_PHASE:
2476 case FSG_STATE_DATA_PHASE:
2477 case FSG_STATE_STATUS_PHASE:
2478 case FSG_STATE_IDLE:
2484 /*-------------------------------------------------------------------------*/
2486 static int fsg_main_thread(void *common_)
2488 struct fsg_common *common = common_;
2491 * Allow the thread to be killed by a signal, but set the signal mask
2492 * to block everything but INT, TERM, KILL, and USR1.
2494 allow_signal(SIGINT);
2495 allow_signal(SIGTERM);
2496 allow_signal(SIGKILL);
2497 allow_signal(SIGUSR1);
2499 /* Allow the thread to be frozen */
2503 * Arrange for userspace references to be interpreted as kernel
2504 * pointers. That way we can pass a kernel pointer to a routine
2505 * that expects a __user pointer and it will work okay.
2510 while (common->state != FSG_STATE_TERMINATED) {
2511 if (exception_in_progress(common) || signal_pending(current)) {
2512 handle_exception(common);
2516 if (!common->running) {
2517 sleep_thread(common);
2521 if (get_next_command(common))
2524 spin_lock_irq(&common->lock);
2525 if (!exception_in_progress(common))
2526 common->state = FSG_STATE_DATA_PHASE;
2527 spin_unlock_irq(&common->lock);
2529 if (do_scsi_command(common) || finish_reply(common))
2532 spin_lock_irq(&common->lock);
2533 if (!exception_in_progress(common))
2534 common->state = FSG_STATE_STATUS_PHASE;
2535 spin_unlock_irq(&common->lock);
2537 if (send_status(common))
2540 spin_lock_irq(&common->lock);
2541 if (!exception_in_progress(common))
2542 common->state = FSG_STATE_IDLE;
2543 spin_unlock_irq(&common->lock);
2546 spin_lock_irq(&common->lock);
2547 common->thread_task = NULL;
2548 spin_unlock_irq(&common->lock);
2550 if (!common->ops || !common->ops->thread_exits
2551 || common->ops->thread_exits(common) < 0) {
2552 struct fsg_lun **curlun_it = common->luns;
2553 unsigned i = common->nluns;
2555 down_write(&common->filesem);
2556 for (; i--; ++curlun_it) {
2557 struct fsg_lun *curlun = *curlun_it;
2558 if (!curlun || !fsg_lun_is_open(curlun))
2561 fsg_lun_close(curlun);
2562 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
2564 up_write(&common->filesem);
2567 /* Let fsg_unbind() know the thread has exited */
2568 complete_and_exit(&common->thread_notifier, 0);
2572 /*************************** DEVICE ATTRIBUTES ***************************/
2574 static ssize_t ro_show(struct device *dev, struct device_attribute *attr, char *buf)
2576 return fsg_show_ro(dev, attr, buf);
2579 static ssize_t nofua_show(struct device *dev, struct device_attribute *attr,
2582 return fsg_show_nofua(dev, attr, buf);
2585 static ssize_t file_show(struct device *dev, struct device_attribute *attr,
2588 return fsg_show_file(dev, attr, buf);
2591 static ssize_t ro_store(struct device *dev, struct device_attribute *attr,
2592 const char *buf, size_t count)
2594 return fsg_store_ro(dev, attr, buf, count);
2597 static ssize_t nofua_store(struct device *dev, struct device_attribute *attr,
2598 const char *buf, size_t count)
2600 return fsg_store_nofua(dev, attr, buf, count);
2603 static ssize_t file_store(struct device *dev, struct device_attribute *attr,
2604 const char *buf, size_t count)
2606 return fsg_store_file(dev, attr, buf, count);
2609 static DEVICE_ATTR_RW(ro);
2610 static DEVICE_ATTR_RW(nofua);
2611 static DEVICE_ATTR_RW(file);
2613 static struct device_attribute dev_attr_ro_cdrom = __ATTR_RO(ro);
2614 static struct device_attribute dev_attr_file_nonremovable = __ATTR_RO(file);
2617 /****************************** FSG COMMON ******************************/
2619 static void fsg_common_release(struct kref *ref);
2621 static void fsg_lun_release(struct device *dev)
2623 /* Nothing needs to be done */
2626 void fsg_common_get(struct fsg_common *common)
2628 kref_get(&common->ref);
2631 void fsg_common_put(struct fsg_common *common)
2633 kref_put(&common->ref, fsg_common_release);
2636 /* check if fsg_num_buffers is within a valid range */
2637 static inline int fsg_num_buffers_validate(unsigned int fsg_num_buffers)
2639 if (fsg_num_buffers >= 2 && fsg_num_buffers <= 4)
2641 pr_err("fsg_num_buffers %u is out of range (%d to %d)\n",
2642 fsg_num_buffers, 2, 4);
2646 static struct fsg_common *fsg_common_setup(struct fsg_common *common)
2649 common = kzalloc(sizeof(*common), GFP_KERNEL);
2651 return ERR_PTR(-ENOMEM);
2652 common->free_storage_on_release = 1;
2654 memset(common, 0, sizeof(*common));
2655 common->free_storage_on_release = 0;
2657 init_rwsem(&common->filesem);
2658 spin_lock_init(&common->lock);
2659 kref_init(&common->ref);
2660 init_completion(&common->thread_notifier);
2661 init_waitqueue_head(&common->fsg_wait);
2662 common->state = FSG_STATE_TERMINATED;
2667 void fsg_common_set_sysfs(struct fsg_common *common, bool sysfs)
2669 common->sysfs = sysfs;
2672 static void _fsg_common_free_buffers(struct fsg_buffhd *buffhds, unsigned n)
2675 struct fsg_buffhd *bh = buffhds;
2684 int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n)
2686 struct fsg_buffhd *bh, *buffhds;
2689 rc = fsg_num_buffers_validate(n);
2693 buffhds = kcalloc(n, sizeof(*buffhds), GFP_KERNEL);
2697 /* Data buffers cyclic list */
2700 goto buffhds_first_it;
2705 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2706 if (unlikely(!bh->buf))
2711 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
2712 common->fsg_num_buffers = n;
2713 common->buffhds = buffhds;
2719 * "buf"s pointed to by heads after n - i are NULL
2720 * so releasing them won't hurt
2722 _fsg_common_free_buffers(buffhds, n);
2727 static inline void fsg_common_remove_sysfs(struct fsg_lun *lun)
2729 device_remove_file(&lun->dev, &dev_attr_nofua);
2731 * device_remove_file() =>
2733 * here the attr (e.g. dev_attr_ro) is only used to be passed to:
2735 * sysfs_remove_file() =>
2737 * here e.g. both dev_attr_ro_cdrom and dev_attr_ro are in
2738 * the same namespace and
2739 * from here only attr->name is passed to:
2741 * sysfs_hash_and_remove()
2743 * attr->name is the same for dev_attr_ro_cdrom and
2745 * attr->name is the same for dev_attr_file and
2746 * dev_attr_file_nonremovable
2748 * so we don't differentiate between removing e.g. dev_attr_ro_cdrom
2751 device_remove_file(&lun->dev, &dev_attr_ro);
2752 device_remove_file(&lun->dev, &dev_attr_file);
2755 void fsg_common_remove_lun(struct fsg_lun *lun, bool sysfs)
2758 fsg_common_remove_sysfs(lun);
2759 device_unregister(&lun->dev);
2765 static void _fsg_common_remove_luns(struct fsg_common *common, int n)
2769 for (i = 0; i < n; ++i)
2770 if (common->luns[i]) {
2771 fsg_common_remove_lun(common->luns[i], common->sysfs);
2772 common->luns[i] = NULL;
2776 void fsg_common_remove_luns(struct fsg_common *common)
2778 _fsg_common_remove_luns(common, common->nluns);
2781 void fsg_common_free_luns(struct fsg_common *common)
2783 fsg_common_remove_luns(common);
2784 kfree(common->luns);
2785 common->luns = NULL;
2788 int fsg_common_set_nluns(struct fsg_common *common, int nluns)
2790 struct fsg_lun **curlun;
2792 /* Find out how many LUNs there should be */
2793 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2794 pr_err("invalid number of LUNs: %u\n", nluns);
2798 curlun = kcalloc(nluns, sizeof(*curlun), GFP_KERNEL);
2799 if (unlikely(!curlun))
2803 fsg_common_free_luns(common);
2805 common->luns = curlun;
2806 common->nluns = nluns;
2808 pr_info("Number of LUNs=%d\n", common->nluns);
2813 int fsg_common_set_cdev(struct fsg_common *common,
2814 struct usb_composite_dev *cdev, bool can_stall)
2816 struct usb_string *us;
2818 common->gadget = cdev->gadget;
2819 common->ep0 = cdev->gadget->ep0;
2820 common->ep0req = cdev->req;
2821 common->cdev = cdev;
2823 us = usb_gstrings_attach(cdev, fsg_strings_array,
2824 ARRAY_SIZE(fsg_strings));
2828 fsg_intf_desc.iInterface = us[FSG_STRING_INTERFACE].id;
2831 * Some peripheral controllers are known not to be able to
2832 * halt bulk endpoints correctly. If one of them is present,
2835 common->can_stall = can_stall && !(gadget_is_at91(common->gadget));
2840 struct fsg_common *fsg_common_init(struct fsg_common *common,
2841 struct usb_composite_dev *cdev,
2842 struct fsg_config *cfg)
2844 struct usb_gadget *gadget = cdev->gadget;
2845 struct fsg_lun **curlun_it;
2846 struct fsg_lun_config *lcfg;
2851 common = fsg_common_setup(common);
2854 fsg_common_set_sysfs(common, true);
2855 common->state = FSG_STATE_IDLE;
2857 rc = fsg_common_set_num_buffers(common, cfg->fsg_num_buffers);
2859 if (common->free_storage_on_release)
2863 common->ops = cfg->ops;
2864 common->private_data = cfg->private_data;
2866 rc = fsg_common_set_cdev(common, cdev, cfg->can_stall);
2870 rc = fsg_common_set_nluns(common, cfg->nluns);
2873 curlun_it = common->luns;
2875 for (i = 0, lcfg = cfg->luns; i < nluns; ++i, ++curlun_it, ++lcfg) {
2876 struct fsg_lun *curlun;
2878 curlun = kzalloc(sizeof(*curlun), GFP_KERNEL);
2884 *curlun_it = curlun;
2886 curlun->cdrom = !!lcfg->cdrom;
2887 curlun->ro = lcfg->cdrom || lcfg->ro;
2888 curlun->initially_ro = curlun->ro;
2889 curlun->removable = lcfg->removable;
2890 curlun->dev.release = fsg_lun_release;
2891 curlun->dev.parent = &gadget->dev;
2892 /* curlun->dev.driver = &fsg_driver.driver; XXX */
2893 dev_set_drvdata(&curlun->dev, &common->filesem);
2894 dev_set_name(&curlun->dev, "lun%d", i);
2895 curlun->name = dev_name(&curlun->dev);
2897 rc = device_register(&curlun->dev);
2899 INFO(common, "failed to register LUN%d: %d\n", i, rc);
2901 put_device(&curlun->dev);
2906 rc = device_create_file(&curlun->dev,
2908 ? &dev_attr_ro_cdrom
2912 rc = device_create_file(&curlun->dev,
2915 : &dev_attr_file_nonremovable);
2918 rc = device_create_file(&curlun->dev, &dev_attr_nofua);
2922 if (lcfg->filename) {
2923 rc = fsg_lun_open(curlun, lcfg->filename);
2926 } else if (!curlun->removable) {
2927 ERROR(common, "no file given for LUN%d\n", i);
2934 /* Prepare inquiryString */
2935 i = get_default_bcdDevice();
2936 snprintf(common->inquiry_string, sizeof common->inquiry_string,
2937 "%-8s%-16s%04x", cfg->vendor_name ?: "Linux",
2938 /* Assume product name dependent on the first LUN */
2939 cfg->product_name ?: ((*common->luns)->cdrom
2941 : "File-Stor Gadget"),
2945 /* Tell the thread to start working */
2946 common->thread_task =
2947 kthread_create(fsg_main_thread, common, "file-storage");
2948 if (IS_ERR(common->thread_task)) {
2949 rc = PTR_ERR(common->thread_task);
2954 INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2955 INFO(common, "Number of LUNs=%d\n", common->nluns);
2957 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2958 for (i = 0, nluns = common->nluns, curlun_it = common->luns;
2961 struct fsg_lun *curlun = *curlun_it;
2962 char *p = "(no medium)";
2963 if (fsg_lun_is_open(curlun)) {
2966 p = d_path(&curlun->filp->f_path,
2972 LINFO(curlun, "LUN: %s%s%sfile: %s\n",
2973 curlun->removable ? "removable " : "",
2974 curlun->ro ? "read only " : "",
2975 curlun->cdrom ? "CD-ROM " : "",
2980 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
2982 wake_up_process(common->thread_task);
2987 common->nluns = i + 1;
2989 common->state = FSG_STATE_TERMINATED; /* The thread is dead */
2990 /* Call fsg_common_release() directly, ref might be not initialised. */
2991 fsg_common_release(&common->ref);
2995 static void fsg_common_release(struct kref *ref)
2997 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
2999 /* If the thread isn't already dead, tell it to exit now */
3000 if (common->state != FSG_STATE_TERMINATED) {
3001 raise_exception(common, FSG_STATE_EXIT);
3002 wait_for_completion(&common->thread_notifier);
3005 if (likely(common->luns)) {
3006 struct fsg_lun **lun_it = common->luns;
3007 unsigned i = common->nluns;
3009 /* In error recovery common->nluns may be zero. */
3010 for (; i; --i, ++lun_it) {
3011 struct fsg_lun *lun = *lun_it;
3015 fsg_common_remove_sysfs(lun);
3018 device_unregister(&lun->dev);
3022 kfree(common->luns);
3025 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
3026 if (common->free_storage_on_release)
3031 /*-------------------------------------------------------------------------*/
3033 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
3035 struct fsg_dev *fsg = fsg_from_func(f);
3036 struct fsg_common *common = fsg->common;
3038 DBG(fsg, "unbind\n");
3039 if (fsg->common->fsg == fsg) {
3040 fsg->common->new_fsg = NULL;
3041 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
3042 /* FIXME: make interruptible or killable somehow? */
3043 wait_event(common->fsg_wait, common->fsg != fsg);
3046 fsg_common_put(common);
3047 usb_free_all_descriptors(&fsg->function);
3051 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
3053 struct fsg_dev *fsg = fsg_from_func(f);
3054 struct usb_gadget *gadget = c->cdev->gadget;
3060 fsg->gadget = gadget;
3063 i = usb_interface_id(c, f);
3066 fsg_intf_desc.bInterfaceNumber = i;
3067 fsg->interface_number = i;
3069 /* Find all the endpoints we will use */
3070 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
3073 ep->driver_data = fsg->common; /* claim the endpoint */
3076 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
3079 ep->driver_data = fsg->common; /* claim the endpoint */
3082 /* Assume endpoint addresses are the same for both speeds */
3083 fsg_hs_bulk_in_desc.bEndpointAddress =
3084 fsg_fs_bulk_in_desc.bEndpointAddress;
3085 fsg_hs_bulk_out_desc.bEndpointAddress =
3086 fsg_fs_bulk_out_desc.bEndpointAddress;
3088 /* Calculate bMaxBurst, we know packet size is 1024 */
3089 max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15);
3091 fsg_ss_bulk_in_desc.bEndpointAddress =
3092 fsg_fs_bulk_in_desc.bEndpointAddress;
3093 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
3095 fsg_ss_bulk_out_desc.bEndpointAddress =
3096 fsg_fs_bulk_out_desc.bEndpointAddress;
3097 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
3099 ret = usb_assign_descriptors(f, fsg_fs_function, fsg_hs_function,
3107 ERROR(fsg, "unable to autoconfigure all endpoints\n");
3111 /****************************** ADD FUNCTION ******************************/
3113 static int fsg_bind_config(struct usb_composite_dev *cdev,
3114 struct usb_configuration *c,
3115 struct fsg_common *common)
3117 struct fsg_dev *fsg;
3120 fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
3124 fsg->function.name = FSG_DRIVER_DESC;
3125 fsg->function.bind = fsg_bind;
3126 fsg->function.unbind = fsg_unbind;
3127 fsg->function.setup = fsg_setup;
3128 fsg->function.set_alt = fsg_set_alt;
3129 fsg->function.disable = fsg_disable;
3131 fsg->common = common;
3133 * Our caller holds a reference to common structure so we
3134 * don't have to be worry about it being freed until we return
3135 * from this function. So instead of incrementing counter now
3136 * and decrement in error recovery we increment it only when
3137 * call to usb_add_function() was successful.
3140 rc = usb_add_function(c, &fsg->function);
3144 fsg_common_get(fsg->common);
3149 /************************* Module parameters *************************/
3152 void fsg_config_from_params(struct fsg_config *cfg,
3153 const struct fsg_module_parameters *params,
3154 unsigned int fsg_num_buffers)
3156 struct fsg_lun_config *lun;
3159 /* Configure LUNs */
3161 min(params->luns ?: (params->file_count ?: 1u),
3162 (unsigned)FSG_MAX_LUNS);
3163 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3164 lun->ro = !!params->ro[i];
3165 lun->cdrom = !!params->cdrom[i];
3166 lun->removable = !!params->removable[i];
3168 params->file_count > i && params->file[i][0]
3173 /* Let MSF use defaults */
3174 cfg->vendor_name = NULL;
3175 cfg->product_name = NULL;
3178 cfg->private_data = NULL;
3181 cfg->can_stall = params->stall;
3182 cfg->fsg_num_buffers = fsg_num_buffers;