2 * f_mass_storage.c -- Mass Storage USB Composite Function
4 * Copyright (C) 2003-2008 Alan Stern
5 * Copyright (C) 2009 Samsung Electronics
6 * Author: Michal Nazarewicz <mina86@mina86.com>
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions, and the following disclaimer,
14 * without modification.
15 * 2. Redistributions in binary form must reproduce the above copyright
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17 * documentation and/or other materials provided with the distribution.
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19 * to endorse or promote products derived from this software without
20 * specific prior written permission.
22 * ALTERNATIVELY, this software may be distributed under the terms of the
23 * GNU General Public License ("GPL") as published by the Free Software
24 * Foundation, either version 2 of that License or (at your option) any
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
28 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
29 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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35 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
36 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
37 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
41 * The Mass Storage Function acts as a USB Mass Storage device,
42 * appearing to the host as a disk drive or as a CD-ROM drive. In
43 * addition to providing an example of a genuinely useful composite
44 * function for a USB device, it also illustrates a technique of
45 * double-buffering for increased throughput.
47 * For more information about MSF and in particular its module
48 * parameters and sysfs interface read the
49 * <Documentation/usb/mass-storage.txt> file.
53 * MSF is configured by specifying a fsg_config structure. It has the
56 * nluns Number of LUNs function have (anywhere from 1
58 * luns An array of LUN configuration values. This
59 * should be filled for each LUN that
60 * function will include (ie. for "nluns"
61 * LUNs). Each element of the array has
62 * the following fields:
63 * ->filename The path to the backing file for the LUN.
64 * Required if LUN is not marked as
66 * ->ro Flag specifying access to the LUN shall be
67 * read-only. This is implied if CD-ROM
68 * emulation is enabled as well as when
69 * it was impossible to open "filename"
71 * ->removable Flag specifying that LUN shall be indicated as
73 * ->cdrom Flag specifying that LUN shall be reported as
75 * ->nofua Flag specifying that FUA flag in SCSI WRITE(10,12)
76 * commands for this LUN shall be ignored.
80 * release Information used as a reply to INQUIRY
81 * request. To use default set to NULL,
82 * NULL, 0xffff respectively. The first
83 * field should be 8 and the second 16
86 * can_stall Set to permit function to halt bulk endpoints.
87 * Disabled on some USB devices known not
88 * to work correctly. You should set it
91 * If "removable" is not set for a LUN then a backing file must be
92 * specified. If it is set, then NULL filename means the LUN's medium
93 * is not loaded (an empty string as "filename" in the fsg_config
94 * structure causes error). The CD-ROM emulation includes a single
95 * data track and no audio tracks; hence there need be only one
96 * backing file per LUN.
98 * This function is heavily based on "File-backed Storage Gadget" by
99 * Alan Stern which in turn is heavily based on "Gadget Zero" by David
100 * Brownell. The driver's SCSI command interface was based on the
101 * "Information technology - Small Computer System Interface - 2"
102 * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
103 * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
104 * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
105 * was based on the "Universal Serial Bus Mass Storage Class UFI
106 * Command Specification" document, Revision 1.0, December 14, 1998,
108 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
114 * The MSF is fairly straightforward. There is a main kernel
115 * thread that handles most of the work. Interrupt routines field
116 * callbacks from the controller driver: bulk- and interrupt-request
117 * completion notifications, endpoint-0 events, and disconnect events.
118 * Completion events are passed to the main thread by wakeup calls. Many
119 * ep0 requests are handled at interrupt time, but SetInterface,
120 * SetConfiguration, and device reset requests are forwarded to the
121 * thread in the form of "exceptions" using SIGUSR1 signals (since they
122 * should interrupt any ongoing file I/O operations).
124 * The thread's main routine implements the standard command/data/status
125 * parts of a SCSI interaction. It and its subroutines are full of tests
126 * for pending signals/exceptions -- all this polling is necessary since
127 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
128 * indication that the driver really wants to be running in userspace.)
129 * An important point is that so long as the thread is alive it keeps an
130 * open reference to the backing file. This will prevent unmounting
131 * the backing file's underlying filesystem and could cause problems
132 * during system shutdown, for example. To prevent such problems, the
133 * thread catches INT, TERM, and KILL signals and converts them into
136 * In normal operation the main thread is started during the gadget's
137 * fsg_bind() callback and stopped during fsg_unbind(). But it can
138 * also exit when it receives a signal, and there's no point leaving
139 * the gadget running when the thread is dead. As of this moment, MSF
140 * provides no way to deregister the gadget when thread dies -- maybe
141 * a callback functions is needed.
143 * To provide maximum throughput, the driver uses a circular pipeline of
144 * buffer heads (struct fsg_buffhd). In principle the pipeline can be
145 * arbitrarily long; in practice the benefits don't justify having more
146 * than 2 stages (i.e., double buffering). But it helps to think of the
147 * pipeline as being a long one. Each buffer head contains a bulk-in and
148 * a bulk-out request pointer (since the buffer can be used for both
149 * output and input -- directions always are given from the host's
150 * point of view) as well as a pointer to the buffer and various state
153 * Use of the pipeline follows a simple protocol. There is a variable
154 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
155 * At any time that buffer head may still be in use from an earlier
156 * request, so each buffer head has a state variable indicating whether
157 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
158 * buffer head to be EMPTY, filling the buffer either by file I/O or by
159 * USB I/O (during which the buffer head is BUSY), and marking the buffer
160 * head FULL when the I/O is complete. Then the buffer will be emptied
161 * (again possibly by USB I/O, during which it is marked BUSY) and
162 * finally marked EMPTY again (possibly by a completion routine).
164 * A module parameter tells the driver to avoid stalling the bulk
165 * endpoints wherever the transport specification allows. This is
166 * necessary for some UDCs like the SuperH, which cannot reliably clear a
167 * halt on a bulk endpoint. However, under certain circumstances the
168 * Bulk-only specification requires a stall. In such cases the driver
169 * will halt the endpoint and set a flag indicating that it should clear
170 * the halt in software during the next device reset. Hopefully this
171 * will permit everything to work correctly. Furthermore, although the
172 * specification allows the bulk-out endpoint to halt when the host sends
173 * too much data, implementing this would cause an unavoidable race.
174 * The driver will always use the "no-stall" approach for OUT transfers.
176 * One subtle point concerns sending status-stage responses for ep0
177 * requests. Some of these requests, such as device reset, can involve
178 * interrupting an ongoing file I/O operation, which might take an
179 * arbitrarily long time. During that delay the host might give up on
180 * the original ep0 request and issue a new one. When that happens the
181 * driver should not notify the host about completion of the original
182 * request, as the host will no longer be waiting for it. So the driver
183 * assigns to each ep0 request a unique tag, and it keeps track of the
184 * tag value of the request associated with a long-running exception
185 * (device-reset, interface-change, or configuration-change). When the
186 * exception handler is finished, the status-stage response is submitted
187 * only if the current ep0 request tag is equal to the exception request
188 * tag. Thus only the most recently received ep0 request will get a
189 * status-stage response.
191 * Warning: This driver source file is too long. It ought to be split up
192 * into a header file plus about 3 separate .c files, to handle the details
193 * of the Gadget, USB Mass Storage, and SCSI protocols.
197 /* #define VERBOSE_DEBUG */
198 /* #define DUMP_MSGS */
200 #include <linux/blkdev.h>
201 #include <linux/completion.h>
202 #include <linux/dcache.h>
203 #include <linux/delay.h>
204 #include <linux/device.h>
205 #include <linux/fcntl.h>
206 #include <linux/file.h>
207 #include <linux/fs.h>
208 #include <linux/kref.h>
209 #include <linux/kthread.h>
210 #include <linux/limits.h>
211 #include <linux/rwsem.h>
212 #include <linux/slab.h>
213 #include <linux/spinlock.h>
214 #include <linux/string.h>
215 #include <linux/freezer.h>
216 #include <linux/module.h>
217 #include <linux/uaccess.h>
219 #include <linux/usb/ch9.h>
220 #include <linux/usb/gadget.h>
221 #include <linux/usb/composite.h>
223 #include "configfs.h"
226 /*------------------------------------------------------------------------*/
228 #define FSG_DRIVER_DESC "Mass Storage Function"
229 #define FSG_DRIVER_VERSION "2009/09/11"
231 static const char fsg_string_interface[] = "Mass Storage";
233 #include "storage_common.h"
234 #include "f_mass_storage.h"
236 /* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
237 static struct usb_string fsg_strings[] = {
238 {FSG_STRING_INTERFACE, fsg_string_interface},
242 static struct usb_gadget_strings fsg_stringtab = {
243 .language = 0x0409, /* en-us */
244 .strings = fsg_strings,
247 static struct usb_gadget_strings *fsg_strings_array[] = {
252 /*-------------------------------------------------------------------------*/
257 /* Data shared by all the FSG instances. */
259 struct usb_gadget *gadget;
260 struct usb_composite_dev *cdev;
261 struct fsg_dev *fsg, *new_fsg;
262 wait_queue_head_t fsg_wait;
264 /* filesem protects: backing files in use */
265 struct rw_semaphore filesem;
267 /* lock protects: state, all the req_busy's */
270 struct usb_ep *ep0; /* Copy of gadget->ep0 */
271 struct usb_request *ep0req; /* Copy of cdev->req */
272 unsigned int ep0_req_tag;
274 struct fsg_buffhd *next_buffhd_to_fill;
275 struct fsg_buffhd *next_buffhd_to_drain;
276 struct fsg_buffhd *buffhds;
277 unsigned int fsg_num_buffers;
280 u8 cmnd[MAX_COMMAND_SIZE];
283 struct fsg_lun *luns[FSG_MAX_LUNS];
284 struct fsg_lun *curlun;
286 unsigned int bulk_out_maxpacket;
287 enum fsg_state state; /* For exception handling */
288 unsigned int exception_req_tag;
290 enum data_direction data_dir;
292 u32 data_size_from_cmnd;
297 unsigned int can_stall:1;
298 unsigned int free_storage_on_release:1;
299 unsigned int phase_error:1;
300 unsigned int short_packet_received:1;
301 unsigned int bad_lun_okay:1;
302 unsigned int running:1;
303 unsigned int sysfs:1;
305 int thread_wakeup_needed;
306 struct completion thread_notifier;
307 struct task_struct *thread_task;
309 /* Callback functions. */
310 const struct fsg_operations *ops;
311 /* Gadget's private data. */
315 * Vendor (8 chars), product (16 chars), release (4
316 * hexadecimal digits) and NUL byte
318 char inquiry_string[8 + 16 + 4 + 1];
324 struct usb_function function;
325 struct usb_gadget *gadget; /* Copy of cdev->gadget */
326 struct fsg_common *common;
328 u16 interface_number;
330 unsigned int bulk_in_enabled:1;
331 unsigned int bulk_out_enabled:1;
333 unsigned long atomic_bitflags;
334 #define IGNORE_BULK_OUT 0
336 struct usb_ep *bulk_in;
337 struct usb_ep *bulk_out;
340 static inline int __fsg_is_set(struct fsg_common *common,
341 const char *func, unsigned line)
345 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
350 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
352 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
354 return container_of(f, struct fsg_dev, function);
357 typedef void (*fsg_routine_t)(struct fsg_dev *);
359 static int exception_in_progress(struct fsg_common *common)
361 return common->state > FSG_STATE_IDLE;
364 /* Make bulk-out requests be divisible by the maxpacket size */
365 static void set_bulk_out_req_length(struct fsg_common *common,
366 struct fsg_buffhd *bh, unsigned int length)
370 bh->bulk_out_intended_length = length;
371 rem = length % common->bulk_out_maxpacket;
373 length += common->bulk_out_maxpacket - rem;
374 bh->outreq->length = length;
378 /*-------------------------------------------------------------------------*/
380 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
384 if (ep == fsg->bulk_in)
386 else if (ep == fsg->bulk_out)
390 DBG(fsg, "%s set halt\n", name);
391 return usb_ep_set_halt(ep);
395 /*-------------------------------------------------------------------------*/
397 /* These routines may be called in process context or in_irq */
399 /* Caller must hold fsg->lock */
400 static void wakeup_thread(struct fsg_common *common)
402 smp_wmb(); /* ensure the write of bh->state is complete */
403 /* Tell the main thread that something has happened */
404 common->thread_wakeup_needed = 1;
405 if (common->thread_task)
406 wake_up_process(common->thread_task);
409 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
414 * Do nothing if a higher-priority exception is already in progress.
415 * If a lower-or-equal priority exception is in progress, preempt it
416 * and notify the main thread by sending it a signal.
418 spin_lock_irqsave(&common->lock, flags);
419 if (common->state <= new_state) {
420 common->exception_req_tag = common->ep0_req_tag;
421 common->state = new_state;
422 if (common->thread_task)
423 send_sig_info(SIGUSR1, SEND_SIG_FORCED,
424 common->thread_task);
426 spin_unlock_irqrestore(&common->lock, flags);
430 /*-------------------------------------------------------------------------*/
432 static int ep0_queue(struct fsg_common *common)
436 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
437 common->ep0->driver_data = common;
438 if (rc != 0 && rc != -ESHUTDOWN) {
439 /* We can't do much more than wait for a reset */
440 WARNING(common, "error in submission: %s --> %d\n",
441 common->ep0->name, rc);
447 /*-------------------------------------------------------------------------*/
449 /* Completion handlers. These always run in_irq. */
451 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
453 struct fsg_common *common = ep->driver_data;
454 struct fsg_buffhd *bh = req->context;
456 if (req->status || req->actual != req->length)
457 DBG(common, "%s --> %d, %u/%u\n", __func__,
458 req->status, req->actual, req->length);
459 if (req->status == -ECONNRESET) /* Request was cancelled */
460 usb_ep_fifo_flush(ep);
462 /* Hold the lock while we update the request and buffer states */
464 spin_lock(&common->lock);
466 bh->state = BUF_STATE_EMPTY;
467 wakeup_thread(common);
468 spin_unlock(&common->lock);
471 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
473 struct fsg_common *common = ep->driver_data;
474 struct fsg_buffhd *bh = req->context;
476 dump_msg(common, "bulk-out", req->buf, req->actual);
477 if (req->status || req->actual != bh->bulk_out_intended_length)
478 DBG(common, "%s --> %d, %u/%u\n", __func__,
479 req->status, req->actual, bh->bulk_out_intended_length);
480 if (req->status == -ECONNRESET) /* Request was cancelled */
481 usb_ep_fifo_flush(ep);
483 /* Hold the lock while we update the request and buffer states */
485 spin_lock(&common->lock);
487 bh->state = BUF_STATE_FULL;
488 wakeup_thread(common);
489 spin_unlock(&common->lock);
492 static int _fsg_common_get_max_lun(struct fsg_common *common)
494 int i = ARRAY_SIZE(common->luns) - 1;
496 while (i >= 0 && !common->luns[i])
502 static int fsg_setup(struct usb_function *f,
503 const struct usb_ctrlrequest *ctrl)
505 struct fsg_dev *fsg = fsg_from_func(f);
506 struct usb_request *req = fsg->common->ep0req;
507 u16 w_index = le16_to_cpu(ctrl->wIndex);
508 u16 w_value = le16_to_cpu(ctrl->wValue);
509 u16 w_length = le16_to_cpu(ctrl->wLength);
511 if (!fsg_is_set(fsg->common))
514 ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
517 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
519 switch (ctrl->bRequest) {
521 case US_BULK_RESET_REQUEST:
522 if (ctrl->bRequestType !=
523 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
525 if (w_index != fsg->interface_number || w_value != 0 ||
530 * Raise an exception to stop the current operation
531 * and reinitialize our state.
533 DBG(fsg, "bulk reset request\n");
534 raise_exception(fsg->common, FSG_STATE_RESET);
535 return USB_GADGET_DELAYED_STATUS;
537 case US_BULK_GET_MAX_LUN:
538 if (ctrl->bRequestType !=
539 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
541 if (w_index != fsg->interface_number || w_value != 0 ||
544 VDBG(fsg, "get max LUN\n");
545 *(u8 *)req->buf = _fsg_common_get_max_lun(fsg->common);
547 /* Respond with data/status */
548 req->length = min((u16)1, w_length);
549 return ep0_queue(fsg->common);
553 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
554 ctrl->bRequestType, ctrl->bRequest,
555 le16_to_cpu(ctrl->wValue), w_index, w_length);
560 /*-------------------------------------------------------------------------*/
562 /* All the following routines run in process context */
564 /* Use this for bulk or interrupt transfers, not ep0 */
565 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
566 struct usb_request *req, int *pbusy,
567 enum fsg_buffer_state *state)
571 if (ep == fsg->bulk_in)
572 dump_msg(fsg, "bulk-in", req->buf, req->length);
574 spin_lock_irq(&fsg->common->lock);
576 *state = BUF_STATE_BUSY;
577 spin_unlock_irq(&fsg->common->lock);
579 rc = usb_ep_queue(ep, req, GFP_KERNEL);
581 return; /* All good, we're done */
584 *state = BUF_STATE_EMPTY;
586 /* We can't do much more than wait for a reset */
589 * Note: currently the net2280 driver fails zero-length
590 * submissions if DMA is enabled.
592 if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP && req->length == 0))
593 WARNING(fsg, "error in submission: %s --> %d\n", ep->name, rc);
596 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
598 if (!fsg_is_set(common))
600 start_transfer(common->fsg, common->fsg->bulk_in,
601 bh->inreq, &bh->inreq_busy, &bh->state);
605 static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
607 if (!fsg_is_set(common))
609 start_transfer(common->fsg, common->fsg->bulk_out,
610 bh->outreq, &bh->outreq_busy, &bh->state);
614 static int sleep_thread(struct fsg_common *common, bool can_freeze)
618 /* Wait until a signal arrives or we are woken up */
622 set_current_state(TASK_INTERRUPTIBLE);
623 if (signal_pending(current)) {
627 if (common->thread_wakeup_needed)
631 __set_current_state(TASK_RUNNING);
632 common->thread_wakeup_needed = 0;
633 smp_rmb(); /* ensure the latest bh->state is visible */
638 /*-------------------------------------------------------------------------*/
640 static int do_read(struct fsg_common *common)
642 struct fsg_lun *curlun = common->curlun;
644 struct fsg_buffhd *bh;
647 loff_t file_offset, file_offset_tmp;
652 * Get the starting Logical Block Address and check that it's
655 if (common->cmnd[0] == READ_6)
656 lba = get_unaligned_be24(&common->cmnd[1]);
658 lba = get_unaligned_be32(&common->cmnd[2]);
661 * We allow DPO (Disable Page Out = don't save data in the
662 * cache) and FUA (Force Unit Access = don't read from the
663 * cache), but we don't implement them.
665 if ((common->cmnd[1] & ~0x18) != 0) {
666 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
670 if (lba >= curlun->num_sectors) {
671 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
674 file_offset = ((loff_t) lba) << curlun->blkbits;
676 /* Carry out the file reads */
677 amount_left = common->data_size_from_cmnd;
678 if (unlikely(amount_left == 0))
679 return -EIO; /* No default reply */
683 * Figure out how much we need to read:
684 * Try to read the remaining amount.
685 * But don't read more than the buffer size.
686 * And don't try to read past the end of the file.
688 amount = min(amount_left, FSG_BUFLEN);
689 amount = min((loff_t)amount,
690 curlun->file_length - file_offset);
692 /* Wait for the next buffer to become available */
693 bh = common->next_buffhd_to_fill;
694 while (bh->state != BUF_STATE_EMPTY) {
695 rc = sleep_thread(common, false);
701 * If we were asked to read past the end of file,
702 * end with an empty buffer.
706 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
707 curlun->sense_data_info =
708 file_offset >> curlun->blkbits;
709 curlun->info_valid = 1;
710 bh->inreq->length = 0;
711 bh->state = BUF_STATE_FULL;
715 /* Perform the read */
716 file_offset_tmp = file_offset;
717 nread = vfs_read(curlun->filp,
718 (char __user *)bh->buf,
719 amount, &file_offset_tmp);
720 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
721 (unsigned long long)file_offset, (int)nread);
722 if (signal_pending(current))
726 LDBG(curlun, "error in file read: %d\n", (int)nread);
728 } else if (nread < amount) {
729 LDBG(curlun, "partial file read: %d/%u\n",
731 nread = round_down(nread, curlun->blksize);
733 file_offset += nread;
734 amount_left -= nread;
735 common->residue -= nread;
738 * Except at the end of the transfer, nread will be
739 * equal to the buffer size, which is divisible by the
740 * bulk-in maxpacket size.
742 bh->inreq->length = nread;
743 bh->state = BUF_STATE_FULL;
745 /* If an error occurred, report it and its position */
746 if (nread < amount) {
747 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
748 curlun->sense_data_info =
749 file_offset >> curlun->blkbits;
750 curlun->info_valid = 1;
754 if (amount_left == 0)
755 break; /* No more left to read */
757 /* Send this buffer and go read some more */
759 if (!start_in_transfer(common, bh))
760 /* Don't know what to do if common->fsg is NULL */
762 common->next_buffhd_to_fill = bh->next;
765 return -EIO; /* No default reply */
769 /*-------------------------------------------------------------------------*/
771 static int do_write(struct fsg_common *common)
773 struct fsg_lun *curlun = common->curlun;
775 struct fsg_buffhd *bh;
777 u32 amount_left_to_req, amount_left_to_write;
778 loff_t usb_offset, file_offset, file_offset_tmp;
784 curlun->sense_data = SS_WRITE_PROTECTED;
787 spin_lock(&curlun->filp->f_lock);
788 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
789 spin_unlock(&curlun->filp->f_lock);
792 * Get the starting Logical Block Address and check that it's
795 if (common->cmnd[0] == WRITE_6)
796 lba = get_unaligned_be24(&common->cmnd[1]);
798 lba = get_unaligned_be32(&common->cmnd[2]);
801 * We allow DPO (Disable Page Out = don't save data in the
802 * cache) and FUA (Force Unit Access = write directly to the
803 * medium). We don't implement DPO; we implement FUA by
804 * performing synchronous output.
806 if (common->cmnd[1] & ~0x18) {
807 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
810 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
811 spin_lock(&curlun->filp->f_lock);
812 curlun->filp->f_flags |= O_SYNC;
813 spin_unlock(&curlun->filp->f_lock);
816 if (lba >= curlun->num_sectors) {
817 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
821 /* Carry out the file writes */
823 file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
824 amount_left_to_req = common->data_size_from_cmnd;
825 amount_left_to_write = common->data_size_from_cmnd;
827 while (amount_left_to_write > 0) {
829 /* Queue a request for more data from the host */
830 bh = common->next_buffhd_to_fill;
831 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
834 * Figure out how much we want to get:
835 * Try to get the remaining amount,
836 * but not more than the buffer size.
838 amount = min(amount_left_to_req, FSG_BUFLEN);
840 /* Beyond the end of the backing file? */
841 if (usb_offset >= curlun->file_length) {
844 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
845 curlun->sense_data_info =
846 usb_offset >> curlun->blkbits;
847 curlun->info_valid = 1;
851 /* Get the next buffer */
852 usb_offset += amount;
853 common->usb_amount_left -= amount;
854 amount_left_to_req -= amount;
855 if (amount_left_to_req == 0)
859 * Except at the end of the transfer, amount will be
860 * equal to the buffer size, which is divisible by
861 * the bulk-out maxpacket size.
863 set_bulk_out_req_length(common, bh, amount);
864 if (!start_out_transfer(common, bh))
865 /* Dunno what to do if common->fsg is NULL */
867 common->next_buffhd_to_fill = bh->next;
871 /* Write the received data to the backing file */
872 bh = common->next_buffhd_to_drain;
873 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
874 break; /* We stopped early */
875 if (bh->state == BUF_STATE_FULL) {
877 common->next_buffhd_to_drain = bh->next;
878 bh->state = BUF_STATE_EMPTY;
880 /* Did something go wrong with the transfer? */
881 if (bh->outreq->status != 0) {
882 curlun->sense_data = SS_COMMUNICATION_FAILURE;
883 curlun->sense_data_info =
884 file_offset >> curlun->blkbits;
885 curlun->info_valid = 1;
889 amount = bh->outreq->actual;
890 if (curlun->file_length - file_offset < amount) {
892 "write %u @ %llu beyond end %llu\n",
893 amount, (unsigned long long)file_offset,
894 (unsigned long long)curlun->file_length);
895 amount = curlun->file_length - file_offset;
898 /* Don't accept excess data. The spec doesn't say
899 * what to do in this case. We'll ignore the error.
901 amount = min(amount, bh->bulk_out_intended_length);
903 /* Don't write a partial block */
904 amount = round_down(amount, curlun->blksize);
908 /* Perform the write */
909 file_offset_tmp = file_offset;
910 nwritten = vfs_write(curlun->filp,
911 (char __user *)bh->buf,
912 amount, &file_offset_tmp);
913 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
914 (unsigned long long)file_offset, (int)nwritten);
915 if (signal_pending(current))
916 return -EINTR; /* Interrupted! */
919 LDBG(curlun, "error in file write: %d\n",
922 } else if (nwritten < amount) {
923 LDBG(curlun, "partial file write: %d/%u\n",
924 (int)nwritten, amount);
925 nwritten = round_down(nwritten, curlun->blksize);
927 file_offset += nwritten;
928 amount_left_to_write -= nwritten;
929 common->residue -= nwritten;
931 /* If an error occurred, report it and its position */
932 if (nwritten < amount) {
933 curlun->sense_data = SS_WRITE_ERROR;
934 curlun->sense_data_info =
935 file_offset >> curlun->blkbits;
936 curlun->info_valid = 1;
941 /* Did the host decide to stop early? */
942 if (bh->outreq->actual < bh->bulk_out_intended_length) {
943 common->short_packet_received = 1;
949 /* Wait for something to happen */
950 rc = sleep_thread(common, false);
955 return -EIO; /* No default reply */
959 /*-------------------------------------------------------------------------*/
961 static int do_synchronize_cache(struct fsg_common *common)
963 struct fsg_lun *curlun = common->curlun;
966 /* We ignore the requested LBA and write out all file's
967 * dirty data buffers. */
968 rc = fsg_lun_fsync_sub(curlun);
970 curlun->sense_data = SS_WRITE_ERROR;
975 /*-------------------------------------------------------------------------*/
977 static void invalidate_sub(struct fsg_lun *curlun)
979 struct file *filp = curlun->filp;
980 struct inode *inode = file_inode(filp);
983 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
984 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
987 static int do_verify(struct fsg_common *common)
989 struct fsg_lun *curlun = common->curlun;
991 u32 verification_length;
992 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
993 loff_t file_offset, file_offset_tmp;
999 * Get the starting Logical Block Address and check that it's
1002 lba = get_unaligned_be32(&common->cmnd[2]);
1003 if (lba >= curlun->num_sectors) {
1004 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1009 * We allow DPO (Disable Page Out = don't save data in the
1010 * cache) but we don't implement it.
1012 if (common->cmnd[1] & ~0x10) {
1013 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1017 verification_length = get_unaligned_be16(&common->cmnd[7]);
1018 if (unlikely(verification_length == 0))
1019 return -EIO; /* No default reply */
1021 /* Prepare to carry out the file verify */
1022 amount_left = verification_length << curlun->blkbits;
1023 file_offset = ((loff_t) lba) << curlun->blkbits;
1025 /* Write out all the dirty buffers before invalidating them */
1026 fsg_lun_fsync_sub(curlun);
1027 if (signal_pending(current))
1030 invalidate_sub(curlun);
1031 if (signal_pending(current))
1034 /* Just try to read the requested blocks */
1035 while (amount_left > 0) {
1037 * Figure out how much we need to read:
1038 * Try to read the remaining amount, but not more than
1040 * And don't try to read past the end of the file.
1042 amount = min(amount_left, FSG_BUFLEN);
1043 amount = min((loff_t)amount,
1044 curlun->file_length - file_offset);
1046 curlun->sense_data =
1047 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1048 curlun->sense_data_info =
1049 file_offset >> curlun->blkbits;
1050 curlun->info_valid = 1;
1054 /* Perform the read */
1055 file_offset_tmp = file_offset;
1056 nread = vfs_read(curlun->filp,
1057 (char __user *) bh->buf,
1058 amount, &file_offset_tmp);
1059 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1060 (unsigned long long) file_offset,
1062 if (signal_pending(current))
1066 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1068 } else if (nread < amount) {
1069 LDBG(curlun, "partial file verify: %d/%u\n",
1070 (int)nread, amount);
1071 nread = round_down(nread, curlun->blksize);
1074 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1075 curlun->sense_data_info =
1076 file_offset >> curlun->blkbits;
1077 curlun->info_valid = 1;
1080 file_offset += nread;
1081 amount_left -= nread;
1087 /*-------------------------------------------------------------------------*/
1089 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1091 struct fsg_lun *curlun = common->curlun;
1092 u8 *buf = (u8 *) bh->buf;
1094 if (!curlun) { /* Unsupported LUNs are okay */
1095 common->bad_lun_okay = 1;
1097 buf[0] = TYPE_NO_LUN; /* Unsupported, no device-type */
1098 buf[4] = 31; /* Additional length */
1102 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1103 buf[1] = curlun->removable ? 0x80 : 0;
1104 buf[2] = 2; /* ANSI SCSI level 2 */
1105 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1106 buf[4] = 31; /* Additional length */
1107 buf[5] = 0; /* No special options */
1110 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1114 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1116 struct fsg_lun *curlun = common->curlun;
1117 u8 *buf = (u8 *) bh->buf;
1122 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1124 * If a REQUEST SENSE command is received from an initiator
1125 * with a pending unit attention condition (before the target
1126 * generates the contingent allegiance condition), then the
1127 * target shall either:
1128 * a) report any pending sense data and preserve the unit
1129 * attention condition on the logical unit, or,
1130 * b) report the unit attention condition, may discard any
1131 * pending sense data, and clear the unit attention
1132 * condition on the logical unit for that initiator.
1134 * FSG normally uses option a); enable this code to use option b).
1137 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1138 curlun->sense_data = curlun->unit_attention_data;
1139 curlun->unit_attention_data = SS_NO_SENSE;
1143 if (!curlun) { /* Unsupported LUNs are okay */
1144 common->bad_lun_okay = 1;
1145 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1149 sd = curlun->sense_data;
1150 sdinfo = curlun->sense_data_info;
1151 valid = curlun->info_valid << 7;
1152 curlun->sense_data = SS_NO_SENSE;
1153 curlun->sense_data_info = 0;
1154 curlun->info_valid = 0;
1158 buf[0] = valid | 0x70; /* Valid, current error */
1160 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1161 buf[7] = 18 - 8; /* Additional sense length */
1167 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1169 struct fsg_lun *curlun = common->curlun;
1170 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1171 int pmi = common->cmnd[8];
1172 u8 *buf = (u8 *)bh->buf;
1174 /* Check the PMI and LBA fields */
1175 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1176 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1180 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1181 /* Max logical block */
1182 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1186 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1188 struct fsg_lun *curlun = common->curlun;
1189 int msf = common->cmnd[1] & 0x02;
1190 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1191 u8 *buf = (u8 *)bh->buf;
1193 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1194 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1197 if (lba >= curlun->num_sectors) {
1198 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1203 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1204 store_cdrom_address(&buf[4], msf, lba);
1208 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1210 struct fsg_lun *curlun = common->curlun;
1211 int msf = common->cmnd[1] & 0x02;
1212 int start_track = common->cmnd[6];
1213 u8 *buf = (u8 *)bh->buf;
1215 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1217 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1222 buf[1] = (20-2); /* TOC data length */
1223 buf[2] = 1; /* First track number */
1224 buf[3] = 1; /* Last track number */
1225 buf[5] = 0x16; /* Data track, copying allowed */
1226 buf[6] = 0x01; /* Only track is number 1 */
1227 store_cdrom_address(&buf[8], msf, 0);
1229 buf[13] = 0x16; /* Lead-out track is data */
1230 buf[14] = 0xAA; /* Lead-out track number */
1231 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1235 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1237 struct fsg_lun *curlun = common->curlun;
1238 int mscmnd = common->cmnd[0];
1239 u8 *buf = (u8 *) bh->buf;
1242 int changeable_values, all_pages;
1246 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1247 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1250 pc = common->cmnd[2] >> 6;
1251 page_code = common->cmnd[2] & 0x3f;
1253 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1256 changeable_values = (pc == 1);
1257 all_pages = (page_code == 0x3f);
1260 * Write the mode parameter header. Fixed values are: default
1261 * medium type, no cache control (DPOFUA), and no block descriptors.
1262 * The only variable value is the WriteProtect bit. We will fill in
1263 * the mode data length later.
1266 if (mscmnd == MODE_SENSE) {
1267 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1270 } else { /* MODE_SENSE_10 */
1271 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1273 limit = 65535; /* Should really be FSG_BUFLEN */
1276 /* No block descriptors */
1279 * The mode pages, in numerical order. The only page we support
1280 * is the Caching page.
1282 if (page_code == 0x08 || all_pages) {
1284 buf[0] = 0x08; /* Page code */
1285 buf[1] = 10; /* Page length */
1286 memset(buf+2, 0, 10); /* None of the fields are changeable */
1288 if (!changeable_values) {
1289 buf[2] = 0x04; /* Write cache enable, */
1290 /* Read cache not disabled */
1291 /* No cache retention priorities */
1292 put_unaligned_be16(0xffff, &buf[4]);
1293 /* Don't disable prefetch */
1294 /* Minimum prefetch = 0 */
1295 put_unaligned_be16(0xffff, &buf[8]);
1296 /* Maximum prefetch */
1297 put_unaligned_be16(0xffff, &buf[10]);
1298 /* Maximum prefetch ceiling */
1304 * Check that a valid page was requested and the mode data length
1308 if (!valid_page || len > limit) {
1309 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1313 /* Store the mode data length */
1314 if (mscmnd == MODE_SENSE)
1317 put_unaligned_be16(len - 2, buf0);
1321 static int do_start_stop(struct fsg_common *common)
1323 struct fsg_lun *curlun = common->curlun;
1328 } else if (!curlun->removable) {
1329 curlun->sense_data = SS_INVALID_COMMAND;
1331 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1332 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1333 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1337 loej = common->cmnd[4] & 0x02;
1338 start = common->cmnd[4] & 0x01;
1341 * Our emulation doesn't support mounting; the medium is
1342 * available for use as soon as it is loaded.
1345 if (!fsg_lun_is_open(curlun)) {
1346 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1352 /* Are we allowed to unload the media? */
1353 if (curlun->prevent_medium_removal) {
1354 LDBG(curlun, "unload attempt prevented\n");
1355 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1362 up_read(&common->filesem);
1363 down_write(&common->filesem);
1364 fsg_lun_close(curlun);
1365 up_write(&common->filesem);
1366 down_read(&common->filesem);
1371 static int do_prevent_allow(struct fsg_common *common)
1373 struct fsg_lun *curlun = common->curlun;
1376 if (!common->curlun) {
1378 } else if (!common->curlun->removable) {
1379 common->curlun->sense_data = SS_INVALID_COMMAND;
1383 prevent = common->cmnd[4] & 0x01;
1384 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1385 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1389 if (curlun->prevent_medium_removal && !prevent)
1390 fsg_lun_fsync_sub(curlun);
1391 curlun->prevent_medium_removal = prevent;
1395 static int do_read_format_capacities(struct fsg_common *common,
1396 struct fsg_buffhd *bh)
1398 struct fsg_lun *curlun = common->curlun;
1399 u8 *buf = (u8 *) bh->buf;
1401 buf[0] = buf[1] = buf[2] = 0;
1402 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1405 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1406 /* Number of blocks */
1407 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1408 buf[4] = 0x02; /* Current capacity */
1412 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1414 struct fsg_lun *curlun = common->curlun;
1416 /* We don't support MODE SELECT */
1418 curlun->sense_data = SS_INVALID_COMMAND;
1423 /*-------------------------------------------------------------------------*/
1425 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1429 rc = fsg_set_halt(fsg, fsg->bulk_in);
1431 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1433 if (rc != -EAGAIN) {
1434 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1439 /* Wait for a short time and then try again */
1440 if (msleep_interruptible(100) != 0)
1442 rc = usb_ep_set_halt(fsg->bulk_in);
1447 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1451 DBG(fsg, "bulk-in set wedge\n");
1452 rc = usb_ep_set_wedge(fsg->bulk_in);
1454 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1456 if (rc != -EAGAIN) {
1457 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1462 /* Wait for a short time and then try again */
1463 if (msleep_interruptible(100) != 0)
1465 rc = usb_ep_set_wedge(fsg->bulk_in);
1470 static int throw_away_data(struct fsg_common *common)
1472 struct fsg_buffhd *bh;
1476 for (bh = common->next_buffhd_to_drain;
1477 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1478 bh = common->next_buffhd_to_drain) {
1480 /* Throw away the data in a filled buffer */
1481 if (bh->state == BUF_STATE_FULL) {
1483 bh->state = BUF_STATE_EMPTY;
1484 common->next_buffhd_to_drain = bh->next;
1486 /* A short packet or an error ends everything */
1487 if (bh->outreq->actual < bh->bulk_out_intended_length ||
1488 bh->outreq->status != 0) {
1489 raise_exception(common,
1490 FSG_STATE_ABORT_BULK_OUT);
1496 /* Try to submit another request if we need one */
1497 bh = common->next_buffhd_to_fill;
1498 if (bh->state == BUF_STATE_EMPTY
1499 && common->usb_amount_left > 0) {
1500 amount = min(common->usb_amount_left, FSG_BUFLEN);
1503 * Except at the end of the transfer, amount will be
1504 * equal to the buffer size, which is divisible by
1505 * the bulk-out maxpacket size.
1507 set_bulk_out_req_length(common, bh, amount);
1508 if (!start_out_transfer(common, bh))
1509 /* Dunno what to do if common->fsg is NULL */
1511 common->next_buffhd_to_fill = bh->next;
1512 common->usb_amount_left -= amount;
1516 /* Otherwise wait for something to happen */
1517 rc = sleep_thread(common, true);
1524 static int finish_reply(struct fsg_common *common)
1526 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1529 switch (common->data_dir) {
1531 break; /* Nothing to send */
1534 * If we don't know whether the host wants to read or write,
1535 * this must be CB or CBI with an unknown command. We mustn't
1536 * try to send or receive any data. So stall both bulk pipes
1537 * if we can and wait for a reset.
1539 case DATA_DIR_UNKNOWN:
1540 if (!common->can_stall) {
1542 } else if (fsg_is_set(common)) {
1543 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1544 rc = halt_bulk_in_endpoint(common->fsg);
1546 /* Don't know what to do if common->fsg is NULL */
1551 /* All but the last buffer of data must have already been sent */
1552 case DATA_DIR_TO_HOST:
1553 if (common->data_size == 0) {
1554 /* Nothing to send */
1556 /* Don't know what to do if common->fsg is NULL */
1557 } else if (!fsg_is_set(common)) {
1560 /* If there's no residue, simply send the last buffer */
1561 } else if (common->residue == 0) {
1562 bh->inreq->zero = 0;
1563 if (!start_in_transfer(common, bh))
1565 common->next_buffhd_to_fill = bh->next;
1568 * For Bulk-only, mark the end of the data with a short
1569 * packet. If we are allowed to stall, halt the bulk-in
1570 * endpoint. (Note: This violates the Bulk-Only Transport
1571 * specification, which requires us to pad the data if we
1572 * don't halt the endpoint. Presumably nobody will mind.)
1575 bh->inreq->zero = 1;
1576 if (!start_in_transfer(common, bh))
1578 common->next_buffhd_to_fill = bh->next;
1579 if (common->can_stall)
1580 rc = halt_bulk_in_endpoint(common->fsg);
1585 * We have processed all we want from the data the host has sent.
1586 * There may still be outstanding bulk-out requests.
1588 case DATA_DIR_FROM_HOST:
1589 if (common->residue == 0) {
1590 /* Nothing to receive */
1592 /* Did the host stop sending unexpectedly early? */
1593 } else if (common->short_packet_received) {
1594 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1598 * We haven't processed all the incoming data. Even though
1599 * we may be allowed to stall, doing so would cause a race.
1600 * The controller may already have ACK'ed all the remaining
1601 * bulk-out packets, in which case the host wouldn't see a
1602 * STALL. Not realizing the endpoint was halted, it wouldn't
1603 * clear the halt -- leading to problems later on.
1606 } else if (common->can_stall) {
1607 if (fsg_is_set(common))
1608 fsg_set_halt(common->fsg,
1609 common->fsg->bulk_out);
1610 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1615 * We can't stall. Read in the excess data and throw it
1619 rc = throw_away_data(common);
1626 static int send_status(struct fsg_common *common)
1628 struct fsg_lun *curlun = common->curlun;
1629 struct fsg_buffhd *bh;
1630 struct bulk_cs_wrap *csw;
1632 u8 status = US_BULK_STAT_OK;
1635 /* Wait for the next buffer to become available */
1636 bh = common->next_buffhd_to_fill;
1637 while (bh->state != BUF_STATE_EMPTY) {
1638 rc = sleep_thread(common, true);
1644 sd = curlun->sense_data;
1645 sdinfo = curlun->sense_data_info;
1646 } else if (common->bad_lun_okay)
1649 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1651 if (common->phase_error) {
1652 DBG(common, "sending phase-error status\n");
1653 status = US_BULK_STAT_PHASE;
1654 sd = SS_INVALID_COMMAND;
1655 } else if (sd != SS_NO_SENSE) {
1656 DBG(common, "sending command-failure status\n");
1657 status = US_BULK_STAT_FAIL;
1658 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1660 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1663 /* Store and send the Bulk-only CSW */
1664 csw = (void *)bh->buf;
1666 csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
1667 csw->Tag = common->tag;
1668 csw->Residue = cpu_to_le32(common->residue);
1669 csw->Status = status;
1671 bh->inreq->length = US_BULK_CS_WRAP_LEN;
1672 bh->inreq->zero = 0;
1673 if (!start_in_transfer(common, bh))
1674 /* Don't know what to do if common->fsg is NULL */
1677 common->next_buffhd_to_fill = bh->next;
1682 /*-------------------------------------------------------------------------*/
1685 * Check whether the command is properly formed and whether its data size
1686 * and direction agree with the values we already have.
1688 static int check_command(struct fsg_common *common, int cmnd_size,
1689 enum data_direction data_dir, unsigned int mask,
1690 int needs_medium, const char *name)
1693 unsigned int lun = common->cmnd[1] >> 5;
1694 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1696 struct fsg_lun *curlun;
1699 if (common->data_dir != DATA_DIR_UNKNOWN)
1700 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1702 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1703 name, cmnd_size, dirletter[(int) data_dir],
1704 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1707 * We can't reply at all until we know the correct data direction
1710 if (common->data_size_from_cmnd == 0)
1711 data_dir = DATA_DIR_NONE;
1712 if (common->data_size < common->data_size_from_cmnd) {
1714 * Host data size < Device data size is a phase error.
1715 * Carry out the command, but only transfer as much as
1718 common->data_size_from_cmnd = common->data_size;
1719 common->phase_error = 1;
1721 common->residue = common->data_size;
1722 common->usb_amount_left = common->data_size;
1724 /* Conflicting data directions is a phase error */
1725 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1726 common->phase_error = 1;
1730 /* Verify the length of the command itself */
1731 if (cmnd_size != common->cmnd_size) {
1734 * Special case workaround: There are plenty of buggy SCSI
1735 * implementations. Many have issues with cbw->Length
1736 * field passing a wrong command size. For those cases we
1737 * always try to work around the problem by using the length
1738 * sent by the host side provided it is at least as large
1739 * as the correct command length.
1740 * Examples of such cases would be MS-Windows, which issues
1741 * REQUEST SENSE with cbw->Length == 12 where it should
1742 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1743 * REQUEST SENSE with cbw->Length == 10 where it should
1746 if (cmnd_size <= common->cmnd_size) {
1747 DBG(common, "%s is buggy! Expected length %d "
1748 "but we got %d\n", name,
1749 cmnd_size, common->cmnd_size);
1750 cmnd_size = common->cmnd_size;
1752 common->phase_error = 1;
1757 /* Check that the LUN values are consistent */
1758 if (common->lun != lun)
1759 DBG(common, "using LUN %u from CBW, not LUN %u from CDB\n",
1763 curlun = common->curlun;
1765 if (common->cmnd[0] != REQUEST_SENSE) {
1766 curlun->sense_data = SS_NO_SENSE;
1767 curlun->sense_data_info = 0;
1768 curlun->info_valid = 0;
1771 common->bad_lun_okay = 0;
1774 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1775 * to use unsupported LUNs; all others may not.
1777 if (common->cmnd[0] != INQUIRY &&
1778 common->cmnd[0] != REQUEST_SENSE) {
1779 DBG(common, "unsupported LUN %u\n", common->lun);
1785 * If a unit attention condition exists, only INQUIRY and
1786 * REQUEST SENSE commands are allowed; anything else must fail.
1788 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1789 common->cmnd[0] != INQUIRY &&
1790 common->cmnd[0] != REQUEST_SENSE) {
1791 curlun->sense_data = curlun->unit_attention_data;
1792 curlun->unit_attention_data = SS_NO_SENSE;
1796 /* Check that only command bytes listed in the mask are non-zero */
1797 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1798 for (i = 1; i < cmnd_size; ++i) {
1799 if (common->cmnd[i] && !(mask & (1 << i))) {
1801 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1806 /* If the medium isn't mounted and the command needs to access
1807 * it, return an error. */
1808 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1809 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1816 /* wrapper of check_command for data size in blocks handling */
1817 static int check_command_size_in_blocks(struct fsg_common *common,
1818 int cmnd_size, enum data_direction data_dir,
1819 unsigned int mask, int needs_medium, const char *name)
1822 common->data_size_from_cmnd <<= common->curlun->blkbits;
1823 return check_command(common, cmnd_size, data_dir,
1824 mask, needs_medium, name);
1827 static int do_scsi_command(struct fsg_common *common)
1829 struct fsg_buffhd *bh;
1831 int reply = -EINVAL;
1833 static char unknown[16];
1837 /* Wait for the next buffer to become available for data or status */
1838 bh = common->next_buffhd_to_fill;
1839 common->next_buffhd_to_drain = bh;
1840 while (bh->state != BUF_STATE_EMPTY) {
1841 rc = sleep_thread(common, true);
1845 common->phase_error = 0;
1846 common->short_packet_received = 0;
1848 down_read(&common->filesem); /* We're using the backing file */
1849 switch (common->cmnd[0]) {
1852 common->data_size_from_cmnd = common->cmnd[4];
1853 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1857 reply = do_inquiry(common, bh);
1861 common->data_size_from_cmnd = common->cmnd[4];
1862 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1866 reply = do_mode_select(common, bh);
1869 case MODE_SELECT_10:
1870 common->data_size_from_cmnd =
1871 get_unaligned_be16(&common->cmnd[7]);
1872 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1876 reply = do_mode_select(common, bh);
1880 common->data_size_from_cmnd = common->cmnd[4];
1881 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1882 (1<<1) | (1<<2) | (1<<4), 0,
1885 reply = do_mode_sense(common, bh);
1889 common->data_size_from_cmnd =
1890 get_unaligned_be16(&common->cmnd[7]);
1891 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1892 (1<<1) | (1<<2) | (3<<7), 0,
1895 reply = do_mode_sense(common, bh);
1898 case ALLOW_MEDIUM_REMOVAL:
1899 common->data_size_from_cmnd = 0;
1900 reply = check_command(common, 6, DATA_DIR_NONE,
1902 "PREVENT-ALLOW MEDIUM REMOVAL");
1904 reply = do_prevent_allow(common);
1908 i = common->cmnd[4];
1909 common->data_size_from_cmnd = (i == 0) ? 256 : i;
1910 reply = check_command_size_in_blocks(common, 6,
1915 reply = do_read(common);
1919 common->data_size_from_cmnd =
1920 get_unaligned_be16(&common->cmnd[7]);
1921 reply = check_command_size_in_blocks(common, 10,
1923 (1<<1) | (0xf<<2) | (3<<7), 1,
1926 reply = do_read(common);
1930 common->data_size_from_cmnd =
1931 get_unaligned_be32(&common->cmnd[6]);
1932 reply = check_command_size_in_blocks(common, 12,
1934 (1<<1) | (0xf<<2) | (0xf<<6), 1,
1937 reply = do_read(common);
1941 common->data_size_from_cmnd = 8;
1942 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1943 (0xf<<2) | (1<<8), 1,
1946 reply = do_read_capacity(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,
1955 (3<<7) | (0x1f<<1), 1,
1958 reply = do_read_header(common, bh);
1962 if (!common->curlun || !common->curlun->cdrom)
1964 common->data_size_from_cmnd =
1965 get_unaligned_be16(&common->cmnd[7]);
1966 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1970 reply = do_read_toc(common, bh);
1973 case READ_FORMAT_CAPACITIES:
1974 common->data_size_from_cmnd =
1975 get_unaligned_be16(&common->cmnd[7]);
1976 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1978 "READ FORMAT CAPACITIES");
1980 reply = do_read_format_capacities(common, bh);
1984 common->data_size_from_cmnd = common->cmnd[4];
1985 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1989 reply = do_request_sense(common, bh);
1993 common->data_size_from_cmnd = 0;
1994 reply = check_command(common, 6, DATA_DIR_NONE,
1998 reply = do_start_stop(common);
2001 case SYNCHRONIZE_CACHE:
2002 common->data_size_from_cmnd = 0;
2003 reply = check_command(common, 10, DATA_DIR_NONE,
2004 (0xf<<2) | (3<<7), 1,
2005 "SYNCHRONIZE CACHE");
2007 reply = do_synchronize_cache(common);
2010 case TEST_UNIT_READY:
2011 common->data_size_from_cmnd = 0;
2012 reply = check_command(common, 6, DATA_DIR_NONE,
2018 * Although optional, this command is used by MS-Windows. We
2019 * support a minimal version: BytChk must be 0.
2022 common->data_size_from_cmnd = 0;
2023 reply = check_command(common, 10, DATA_DIR_NONE,
2024 (1<<1) | (0xf<<2) | (3<<7), 1,
2027 reply = do_verify(common);
2031 i = common->cmnd[4];
2032 common->data_size_from_cmnd = (i == 0) ? 256 : i;
2033 reply = check_command_size_in_blocks(common, 6,
2038 reply = do_write(common);
2042 common->data_size_from_cmnd =
2043 get_unaligned_be16(&common->cmnd[7]);
2044 reply = check_command_size_in_blocks(common, 10,
2046 (1<<1) | (0xf<<2) | (3<<7), 1,
2049 reply = do_write(common);
2053 common->data_size_from_cmnd =
2054 get_unaligned_be32(&common->cmnd[6]);
2055 reply = check_command_size_in_blocks(common, 12,
2057 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2060 reply = do_write(common);
2064 * Some mandatory commands that we recognize but don't implement.
2065 * They don't mean much in this setting. It's left as an exercise
2066 * for anyone interested to implement RESERVE and RELEASE in terms
2072 case SEND_DIAGNOSTIC:
2077 common->data_size_from_cmnd = 0;
2078 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2079 reply = check_command(common, common->cmnd_size,
2080 DATA_DIR_UNKNOWN, ~0, 0, unknown);
2082 common->curlun->sense_data = SS_INVALID_COMMAND;
2087 up_read(&common->filesem);
2089 if (reply == -EINTR || signal_pending(current))
2092 /* Set up the single reply buffer for finish_reply() */
2093 if (reply == -EINVAL)
2094 reply = 0; /* Error reply length */
2095 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2096 reply = min((u32)reply, common->data_size_from_cmnd);
2097 bh->inreq->length = reply;
2098 bh->state = BUF_STATE_FULL;
2099 common->residue -= reply;
2100 } /* Otherwise it's already set */
2106 /*-------------------------------------------------------------------------*/
2108 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2110 struct usb_request *req = bh->outreq;
2111 struct bulk_cb_wrap *cbw = req->buf;
2112 struct fsg_common *common = fsg->common;
2114 /* Was this a real packet? Should it be ignored? */
2115 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2118 /* Is the CBW valid? */
2119 if (req->actual != US_BULK_CB_WRAP_LEN ||
2120 cbw->Signature != cpu_to_le32(
2122 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2124 le32_to_cpu(cbw->Signature));
2127 * The Bulk-only spec says we MUST stall the IN endpoint
2128 * (6.6.1), so it's unavoidable. It also says we must
2129 * retain this state until the next reset, but there's
2130 * no way to tell the controller driver it should ignore
2131 * Clear-Feature(HALT) requests.
2133 * We aren't required to halt the OUT endpoint; instead
2134 * we can simply accept and discard any data received
2135 * until the next reset.
2137 wedge_bulk_in_endpoint(fsg);
2138 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2142 /* Is the CBW meaningful? */
2143 if (cbw->Lun >= ARRAY_SIZE(common->luns) ||
2144 cbw->Flags & ~US_BULK_FLAG_IN || cbw->Length <= 0 ||
2145 cbw->Length > MAX_COMMAND_SIZE) {
2146 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2148 cbw->Lun, cbw->Flags, cbw->Length);
2151 * We can do anything we want here, so let's stall the
2152 * bulk pipes if we are allowed to.
2154 if (common->can_stall) {
2155 fsg_set_halt(fsg, fsg->bulk_out);
2156 halt_bulk_in_endpoint(fsg);
2161 /* Save the command for later */
2162 common->cmnd_size = cbw->Length;
2163 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2164 if (cbw->Flags & US_BULK_FLAG_IN)
2165 common->data_dir = DATA_DIR_TO_HOST;
2167 common->data_dir = DATA_DIR_FROM_HOST;
2168 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2169 if (common->data_size == 0)
2170 common->data_dir = DATA_DIR_NONE;
2171 common->lun = cbw->Lun;
2172 if (common->lun < ARRAY_SIZE(common->luns))
2173 common->curlun = common->luns[common->lun];
2175 common->curlun = NULL;
2176 common->tag = cbw->Tag;
2180 static int get_next_command(struct fsg_common *common)
2182 struct fsg_buffhd *bh;
2185 /* Wait for the next buffer to become available */
2186 bh = common->next_buffhd_to_fill;
2187 while (bh->state != BUF_STATE_EMPTY) {
2188 rc = sleep_thread(common, true);
2193 /* Queue a request to read a Bulk-only CBW */
2194 set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
2195 if (!start_out_transfer(common, bh))
2196 /* Don't know what to do if common->fsg is NULL */
2200 * We will drain the buffer in software, which means we
2201 * can reuse it for the next filling. No need to advance
2202 * next_buffhd_to_fill.
2205 /* Wait for the CBW to arrive */
2206 while (bh->state != BUF_STATE_FULL) {
2207 rc = sleep_thread(common, true);
2212 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2213 bh->state = BUF_STATE_EMPTY;
2219 /*-------------------------------------------------------------------------*/
2221 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2222 struct usb_request **preq)
2224 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2227 ERROR(common, "can't allocate request for %s\n", ep->name);
2231 /* Reset interface setting and re-init endpoint state (toggle etc). */
2232 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2234 struct fsg_dev *fsg;
2237 if (common->running)
2238 DBG(common, "reset interface\n");
2241 /* Deallocate the requests */
2245 for (i = 0; i < common->fsg_num_buffers; ++i) {
2246 struct fsg_buffhd *bh = &common->buffhds[i];
2249 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2253 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2258 /* Disable the endpoints */
2259 if (fsg->bulk_in_enabled) {
2260 usb_ep_disable(fsg->bulk_in);
2261 fsg->bulk_in_enabled = 0;
2263 if (fsg->bulk_out_enabled) {
2264 usb_ep_disable(fsg->bulk_out);
2265 fsg->bulk_out_enabled = 0;
2269 wake_up(&common->fsg_wait);
2272 common->running = 0;
2276 common->fsg = new_fsg;
2279 /* Enable the endpoints */
2280 rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
2283 rc = usb_ep_enable(fsg->bulk_in);
2286 fsg->bulk_in->driver_data = common;
2287 fsg->bulk_in_enabled = 1;
2289 rc = config_ep_by_speed(common->gadget, &(fsg->function),
2293 rc = usb_ep_enable(fsg->bulk_out);
2296 fsg->bulk_out->driver_data = common;
2297 fsg->bulk_out_enabled = 1;
2298 common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc);
2299 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2301 /* Allocate the requests */
2302 for (i = 0; i < common->fsg_num_buffers; ++i) {
2303 struct fsg_buffhd *bh = &common->buffhds[i];
2305 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2308 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2311 bh->inreq->buf = bh->outreq->buf = bh->buf;
2312 bh->inreq->context = bh->outreq->context = bh;
2313 bh->inreq->complete = bulk_in_complete;
2314 bh->outreq->complete = bulk_out_complete;
2317 common->running = 1;
2318 for (i = 0; i < ARRAY_SIZE(common->luns); ++i)
2319 if (common->luns[i])
2320 common->luns[i]->unit_attention_data =
2326 /****************************** ALT CONFIGS ******************************/
2328 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2330 struct fsg_dev *fsg = fsg_from_func(f);
2331 fsg->common->new_fsg = fsg;
2332 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2333 return USB_GADGET_DELAYED_STATUS;
2336 static void fsg_disable(struct usb_function *f)
2338 struct fsg_dev *fsg = fsg_from_func(f);
2339 fsg->common->new_fsg = NULL;
2340 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2344 /*-------------------------------------------------------------------------*/
2346 static void handle_exception(struct fsg_common *common)
2350 struct fsg_buffhd *bh;
2351 enum fsg_state old_state;
2352 struct fsg_lun *curlun;
2353 unsigned int exception_req_tag;
2356 * Clear the existing signals. Anything but SIGUSR1 is converted
2357 * into a high-priority EXIT exception.
2361 dequeue_signal_lock(current, ¤t->blocked, &info);
2364 if (sig != SIGUSR1) {
2365 if (common->state < FSG_STATE_EXIT)
2366 DBG(common, "Main thread exiting on signal\n");
2367 raise_exception(common, FSG_STATE_EXIT);
2371 /* Cancel all the pending transfers */
2372 if (likely(common->fsg)) {
2373 for (i = 0; i < common->fsg_num_buffers; ++i) {
2374 bh = &common->buffhds[i];
2376 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2377 if (bh->outreq_busy)
2378 usb_ep_dequeue(common->fsg->bulk_out,
2382 /* Wait until everything is idle */
2385 for (i = 0; i < common->fsg_num_buffers; ++i) {
2386 bh = &common->buffhds[i];
2387 num_active += bh->inreq_busy + bh->outreq_busy;
2389 if (num_active == 0)
2391 if (sleep_thread(common, true))
2395 /* Clear out the controller's fifos */
2396 if (common->fsg->bulk_in_enabled)
2397 usb_ep_fifo_flush(common->fsg->bulk_in);
2398 if (common->fsg->bulk_out_enabled)
2399 usb_ep_fifo_flush(common->fsg->bulk_out);
2403 * Reset the I/O buffer states and pointers, the SCSI
2404 * state, and the exception. Then invoke the handler.
2406 spin_lock_irq(&common->lock);
2408 for (i = 0; i < common->fsg_num_buffers; ++i) {
2409 bh = &common->buffhds[i];
2410 bh->state = BUF_STATE_EMPTY;
2412 common->next_buffhd_to_fill = &common->buffhds[0];
2413 common->next_buffhd_to_drain = &common->buffhds[0];
2414 exception_req_tag = common->exception_req_tag;
2415 old_state = common->state;
2417 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2418 common->state = FSG_STATE_STATUS_PHASE;
2420 for (i = 0; i < ARRAY_SIZE(common->luns); ++i) {
2421 curlun = common->luns[i];
2424 curlun->prevent_medium_removal = 0;
2425 curlun->sense_data = SS_NO_SENSE;
2426 curlun->unit_attention_data = SS_NO_SENSE;
2427 curlun->sense_data_info = 0;
2428 curlun->info_valid = 0;
2430 common->state = FSG_STATE_IDLE;
2432 spin_unlock_irq(&common->lock);
2434 /* Carry out any extra actions required for the exception */
2435 switch (old_state) {
2436 case FSG_STATE_ABORT_BULK_OUT:
2437 send_status(common);
2438 spin_lock_irq(&common->lock);
2439 if (common->state == FSG_STATE_STATUS_PHASE)
2440 common->state = FSG_STATE_IDLE;
2441 spin_unlock_irq(&common->lock);
2444 case FSG_STATE_RESET:
2446 * In case we were forced against our will to halt a
2447 * bulk endpoint, clear the halt now. (The SuperH UDC
2450 if (!fsg_is_set(common))
2452 if (test_and_clear_bit(IGNORE_BULK_OUT,
2453 &common->fsg->atomic_bitflags))
2454 usb_ep_clear_halt(common->fsg->bulk_in);
2456 if (common->ep0_req_tag == exception_req_tag)
2457 ep0_queue(common); /* Complete the status stage */
2460 * Technically this should go here, but it would only be
2461 * a waste of time. Ditto for the INTERFACE_CHANGE and
2462 * CONFIG_CHANGE cases.
2464 /* for (i = 0; i < common->ARRAY_SIZE(common->luns); ++i) */
2465 /* if (common->luns[i]) */
2466 /* common->luns[i]->unit_attention_data = */
2467 /* SS_RESET_OCCURRED; */
2470 case FSG_STATE_CONFIG_CHANGE:
2471 do_set_interface(common, common->new_fsg);
2472 if (common->new_fsg)
2473 usb_composite_setup_continue(common->cdev);
2476 case FSG_STATE_EXIT:
2477 case FSG_STATE_TERMINATED:
2478 do_set_interface(common, NULL); /* Free resources */
2479 spin_lock_irq(&common->lock);
2480 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2481 spin_unlock_irq(&common->lock);
2484 case FSG_STATE_INTERFACE_CHANGE:
2485 case FSG_STATE_DISCONNECT:
2486 case FSG_STATE_COMMAND_PHASE:
2487 case FSG_STATE_DATA_PHASE:
2488 case FSG_STATE_STATUS_PHASE:
2489 case FSG_STATE_IDLE:
2495 /*-------------------------------------------------------------------------*/
2497 static int fsg_main_thread(void *common_)
2499 struct fsg_common *common = common_;
2502 * Allow the thread to be killed by a signal, but set the signal mask
2503 * to block everything but INT, TERM, KILL, and USR1.
2505 allow_signal(SIGINT);
2506 allow_signal(SIGTERM);
2507 allow_signal(SIGKILL);
2508 allow_signal(SIGUSR1);
2510 /* Allow the thread to be frozen */
2514 * Arrange for userspace references to be interpreted as kernel
2515 * pointers. That way we can pass a kernel pointer to a routine
2516 * that expects a __user pointer and it will work okay.
2521 while (common->state != FSG_STATE_TERMINATED) {
2522 if (exception_in_progress(common) || signal_pending(current)) {
2523 handle_exception(common);
2527 if (!common->running) {
2528 sleep_thread(common, true);
2532 if (get_next_command(common))
2535 spin_lock_irq(&common->lock);
2536 if (!exception_in_progress(common))
2537 common->state = FSG_STATE_DATA_PHASE;
2538 spin_unlock_irq(&common->lock);
2540 if (do_scsi_command(common) || finish_reply(common))
2543 spin_lock_irq(&common->lock);
2544 if (!exception_in_progress(common))
2545 common->state = FSG_STATE_STATUS_PHASE;
2546 spin_unlock_irq(&common->lock);
2548 if (send_status(common))
2551 spin_lock_irq(&common->lock);
2552 if (!exception_in_progress(common))
2553 common->state = FSG_STATE_IDLE;
2554 spin_unlock_irq(&common->lock);
2557 spin_lock_irq(&common->lock);
2558 common->thread_task = NULL;
2559 spin_unlock_irq(&common->lock);
2561 if (!common->ops || !common->ops->thread_exits
2562 || common->ops->thread_exits(common) < 0) {
2565 down_write(&common->filesem);
2566 for (i = 0; i < ARRAY_SIZE(common->luns); --i) {
2567 struct fsg_lun *curlun = common->luns[i];
2568 if (!curlun || !fsg_lun_is_open(curlun))
2571 fsg_lun_close(curlun);
2572 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
2574 up_write(&common->filesem);
2577 /* Let fsg_unbind() know the thread has exited */
2578 complete_and_exit(&common->thread_notifier, 0);
2582 /*************************** DEVICE ATTRIBUTES ***************************/
2584 static ssize_t ro_show(struct device *dev, struct device_attribute *attr, char *buf)
2586 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2588 return fsg_show_ro(curlun, buf);
2591 static ssize_t nofua_show(struct device *dev, struct device_attribute *attr,
2594 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2596 return fsg_show_nofua(curlun, buf);
2599 static ssize_t file_show(struct device *dev, struct device_attribute *attr,
2602 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2603 struct rw_semaphore *filesem = dev_get_drvdata(dev);
2605 return fsg_show_file(curlun, filesem, buf);
2608 static ssize_t ro_store(struct device *dev, struct device_attribute *attr,
2609 const char *buf, size_t count)
2611 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2612 struct rw_semaphore *filesem = dev_get_drvdata(dev);
2614 return fsg_store_ro(curlun, filesem, buf, count);
2617 static ssize_t nofua_store(struct device *dev, struct device_attribute *attr,
2618 const char *buf, size_t count)
2620 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2622 return fsg_store_nofua(curlun, buf, count);
2625 static ssize_t file_store(struct device *dev, struct device_attribute *attr,
2626 const char *buf, size_t count)
2628 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2629 struct rw_semaphore *filesem = dev_get_drvdata(dev);
2631 return fsg_store_file(curlun, filesem, buf, count);
2634 static DEVICE_ATTR_RW(nofua);
2635 /* mode wil be set in fsg_lun_attr_is_visible() */
2636 static DEVICE_ATTR(ro, 0, ro_show, ro_store);
2637 static DEVICE_ATTR(file, 0, file_show, file_store);
2639 /****************************** FSG COMMON ******************************/
2641 static void fsg_common_release(struct kref *ref);
2643 static void fsg_lun_release(struct device *dev)
2645 /* Nothing needs to be done */
2648 void fsg_common_get(struct fsg_common *common)
2650 kref_get(&common->ref);
2652 EXPORT_SYMBOL_GPL(fsg_common_get);
2654 void fsg_common_put(struct fsg_common *common)
2656 kref_put(&common->ref, fsg_common_release);
2658 EXPORT_SYMBOL_GPL(fsg_common_put);
2660 /* check if fsg_num_buffers is within a valid range */
2661 static inline int fsg_num_buffers_validate(unsigned int fsg_num_buffers)
2663 #define FSG_MAX_NUM_BUFFERS 32
2665 if (fsg_num_buffers >= 2 && fsg_num_buffers <= FSG_MAX_NUM_BUFFERS)
2667 pr_err("fsg_num_buffers %u is out of range (%d to %d)\n",
2668 fsg_num_buffers, 2, FSG_MAX_NUM_BUFFERS);
2672 static struct fsg_common *fsg_common_setup(struct fsg_common *common)
2675 common = kzalloc(sizeof(*common), GFP_KERNEL);
2677 return ERR_PTR(-ENOMEM);
2678 common->free_storage_on_release = 1;
2680 common->free_storage_on_release = 0;
2682 init_rwsem(&common->filesem);
2683 spin_lock_init(&common->lock);
2684 kref_init(&common->ref);
2685 init_completion(&common->thread_notifier);
2686 init_waitqueue_head(&common->fsg_wait);
2687 common->state = FSG_STATE_TERMINATED;
2688 memset(common->luns, 0, sizeof(common->luns));
2693 void fsg_common_set_sysfs(struct fsg_common *common, bool sysfs)
2695 common->sysfs = sysfs;
2697 EXPORT_SYMBOL_GPL(fsg_common_set_sysfs);
2699 static void _fsg_common_free_buffers(struct fsg_buffhd *buffhds, unsigned n)
2702 struct fsg_buffhd *bh = buffhds;
2711 int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n)
2713 struct fsg_buffhd *bh, *buffhds;
2716 rc = fsg_num_buffers_validate(n);
2720 buffhds = kcalloc(n, sizeof(*buffhds), GFP_KERNEL);
2724 /* Data buffers cyclic list */
2727 goto buffhds_first_it;
2732 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2733 if (unlikely(!bh->buf))
2738 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
2739 common->fsg_num_buffers = n;
2740 common->buffhds = buffhds;
2746 * "buf"s pointed to by heads after n - i are NULL
2747 * so releasing them won't hurt
2749 _fsg_common_free_buffers(buffhds, n);
2753 EXPORT_SYMBOL_GPL(fsg_common_set_num_buffers);
2755 void fsg_common_remove_lun(struct fsg_lun *lun)
2757 if (device_is_registered(&lun->dev))
2758 device_unregister(&lun->dev);
2762 EXPORT_SYMBOL_GPL(fsg_common_remove_lun);
2764 static void _fsg_common_remove_luns(struct fsg_common *common, int n)
2768 for (i = 0; i < n; ++i)
2769 if (common->luns[i]) {
2770 fsg_common_remove_lun(common->luns[i]);
2771 common->luns[i] = NULL;
2775 void fsg_common_remove_luns(struct fsg_common *common)
2777 _fsg_common_remove_luns(common, ARRAY_SIZE(common->luns));
2779 EXPORT_SYMBOL_GPL(fsg_common_remove_luns);
2781 void fsg_common_set_ops(struct fsg_common *common,
2782 const struct fsg_operations *ops)
2786 EXPORT_SYMBOL_GPL(fsg_common_set_ops);
2788 void fsg_common_free_buffers(struct fsg_common *common)
2790 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
2791 common->buffhds = NULL;
2793 EXPORT_SYMBOL_GPL(fsg_common_free_buffers);
2795 int fsg_common_set_cdev(struct fsg_common *common,
2796 struct usb_composite_dev *cdev, bool can_stall)
2798 struct usb_string *us;
2800 common->gadget = cdev->gadget;
2801 common->ep0 = cdev->gadget->ep0;
2802 common->ep0req = cdev->req;
2803 common->cdev = cdev;
2805 us = usb_gstrings_attach(cdev, fsg_strings_array,
2806 ARRAY_SIZE(fsg_strings));
2810 fsg_intf_desc.iInterface = us[FSG_STRING_INTERFACE].id;
2813 * Some peripheral controllers are known not to be able to
2814 * halt bulk endpoints correctly. If one of them is present,
2817 common->can_stall = can_stall &&
2818 gadget_is_stall_supported(common->gadget);
2822 EXPORT_SYMBOL_GPL(fsg_common_set_cdev);
2824 static struct attribute *fsg_lun_dev_attrs[] = {
2826 &dev_attr_file.attr,
2827 &dev_attr_nofua.attr,
2831 static umode_t fsg_lun_dev_is_visible(struct kobject *kobj,
2832 struct attribute *attr, int idx)
2834 struct device *dev = kobj_to_dev(kobj);
2835 struct fsg_lun *lun = fsg_lun_from_dev(dev);
2837 if (attr == &dev_attr_ro.attr)
2838 return lun->cdrom ? S_IRUGO : (S_IWUSR | S_IRUGO);
2839 if (attr == &dev_attr_file.attr)
2840 return lun->removable ? (S_IWUSR | S_IRUGO) : S_IRUGO;
2844 static const struct attribute_group fsg_lun_dev_group = {
2845 .attrs = fsg_lun_dev_attrs,
2846 .is_visible = fsg_lun_dev_is_visible,
2849 static const struct attribute_group *fsg_lun_dev_groups[] = {
2854 int fsg_common_create_lun(struct fsg_common *common, struct fsg_lun_config *cfg,
2855 unsigned int id, const char *name,
2856 const char **name_pfx)
2858 struct fsg_lun *lun;
2862 if (id >= ARRAY_SIZE(common->luns))
2865 if (common->luns[id])
2868 if (!cfg->filename && !cfg->removable) {
2869 pr_err("no file given for LUN%d\n", id);
2873 lun = kzalloc(sizeof(*lun), GFP_KERNEL);
2877 lun->name_pfx = name_pfx;
2879 lun->cdrom = !!cfg->cdrom;
2880 lun->ro = cfg->cdrom || cfg->ro;
2881 lun->initially_ro = lun->ro;
2882 lun->removable = !!cfg->removable;
2884 if (!common->sysfs) {
2885 /* we DON'T own the name!*/
2888 lun->dev.release = fsg_lun_release;
2889 lun->dev.parent = &common->gadget->dev;
2890 lun->dev.groups = fsg_lun_dev_groups;
2891 dev_set_drvdata(&lun->dev, &common->filesem);
2892 dev_set_name(&lun->dev, "%s", name);
2893 lun->name = dev_name(&lun->dev);
2895 rc = device_register(&lun->dev);
2897 pr_info("failed to register LUN%d: %d\n", id, rc);
2898 put_device(&lun->dev);
2903 common->luns[id] = lun;
2905 if (cfg->filename) {
2906 rc = fsg_lun_open(lun, cfg->filename);
2911 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2913 if (fsg_lun_is_open(lun)) {
2916 p = file_path(lun->filp, pathbuf, PATH_MAX);
2921 pr_info("LUN: %s%s%sfile: %s\n",
2922 lun->removable ? "removable " : "",
2923 lun->ro ? "read only " : "",
2924 lun->cdrom ? "CD-ROM " : "",
2931 if (device_is_registered(&lun->dev))
2932 device_unregister(&lun->dev);
2934 common->luns[id] = NULL;
2939 EXPORT_SYMBOL_GPL(fsg_common_create_lun);
2941 int fsg_common_create_luns(struct fsg_common *common, struct fsg_config *cfg)
2943 char buf[8]; /* enough for 100000000 different numbers, decimal */
2946 fsg_common_remove_luns(common);
2948 for (i = 0; i < cfg->nluns; ++i) {
2949 snprintf(buf, sizeof(buf), "lun%d", i);
2950 rc = fsg_common_create_lun(common, &cfg->luns[i], i, buf, NULL);
2955 pr_info("Number of LUNs=%d\n", cfg->nluns);
2960 _fsg_common_remove_luns(common, i);
2963 EXPORT_SYMBOL_GPL(fsg_common_create_luns);
2965 void fsg_common_set_inquiry_string(struct fsg_common *common, const char *vn,
2970 /* Prepare inquiryString */
2971 i = get_default_bcdDevice();
2972 snprintf(common->inquiry_string, sizeof(common->inquiry_string),
2973 "%-8s%-16s%04x", vn ?: "Linux",
2974 /* Assume product name dependent on the first LUN */
2975 pn ?: ((*common->luns)->cdrom
2977 : "File-Stor Gadget"),
2980 EXPORT_SYMBOL_GPL(fsg_common_set_inquiry_string);
2982 int fsg_common_run_thread(struct fsg_common *common)
2984 common->state = FSG_STATE_IDLE;
2985 /* Tell the thread to start working */
2986 common->thread_task =
2987 kthread_create(fsg_main_thread, common, "file-storage");
2988 if (IS_ERR(common->thread_task)) {
2989 common->state = FSG_STATE_TERMINATED;
2990 return PTR_ERR(common->thread_task);
2993 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
2995 wake_up_process(common->thread_task);
2999 EXPORT_SYMBOL_GPL(fsg_common_run_thread);
3001 static void fsg_common_release(struct kref *ref)
3003 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
3006 /* If the thread isn't already dead, tell it to exit now */
3007 if (common->state != FSG_STATE_TERMINATED) {
3008 raise_exception(common, FSG_STATE_EXIT);
3009 wait_for_completion(&common->thread_notifier);
3012 for (i = 0; i < ARRAY_SIZE(common->luns); ++i) {
3013 struct fsg_lun *lun = common->luns[i];
3017 if (device_is_registered(&lun->dev))
3018 device_unregister(&lun->dev);
3022 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
3023 if (common->free_storage_on_release)
3028 /*-------------------------------------------------------------------------*/
3030 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
3032 struct fsg_dev *fsg = fsg_from_func(f);
3033 struct fsg_common *common = fsg->common;
3034 struct usb_gadget *gadget = c->cdev->gadget;
3039 struct fsg_opts *opts;
3041 /* Don't allow to bind if we don't have at least one LUN */
3042 ret = _fsg_common_get_max_lun(common);
3044 pr_err("There should be at least one LUN.\n");
3048 opts = fsg_opts_from_func_inst(f->fi);
3049 if (!opts->no_configfs) {
3050 ret = fsg_common_set_cdev(fsg->common, c->cdev,
3051 fsg->common->can_stall);
3054 fsg_common_set_inquiry_string(fsg->common, NULL, NULL);
3055 ret = fsg_common_run_thread(fsg->common);
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);
3075 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
3080 /* Assume endpoint addresses are the same for both speeds */
3081 fsg_hs_bulk_in_desc.bEndpointAddress =
3082 fsg_fs_bulk_in_desc.bEndpointAddress;
3083 fsg_hs_bulk_out_desc.bEndpointAddress =
3084 fsg_fs_bulk_out_desc.bEndpointAddress;
3086 /* Calculate bMaxBurst, we know packet size is 1024 */
3087 max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15);
3089 fsg_ss_bulk_in_desc.bEndpointAddress =
3090 fsg_fs_bulk_in_desc.bEndpointAddress;
3091 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
3093 fsg_ss_bulk_out_desc.bEndpointAddress =
3094 fsg_fs_bulk_out_desc.bEndpointAddress;
3095 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
3097 ret = usb_assign_descriptors(f, fsg_fs_function, fsg_hs_function,
3105 ERROR(fsg, "unable to autoconfigure all endpoints\n");
3108 /* terminate the thread */
3109 if (fsg->common->state != FSG_STATE_TERMINATED) {
3110 raise_exception(fsg->common, FSG_STATE_EXIT);
3111 wait_for_completion(&fsg->common->thread_notifier);
3116 /****************************** ALLOCATE FUNCTION *************************/
3118 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
3120 struct fsg_dev *fsg = fsg_from_func(f);
3121 struct fsg_common *common = fsg->common;
3123 DBG(fsg, "unbind\n");
3124 if (fsg->common->fsg == fsg) {
3125 fsg->common->new_fsg = NULL;
3126 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
3127 /* FIXME: make interruptible or killable somehow? */
3128 wait_event(common->fsg_wait, common->fsg != fsg);
3131 usb_free_all_descriptors(&fsg->function);
3134 static inline struct fsg_lun_opts *to_fsg_lun_opts(struct config_item *item)
3136 return container_of(to_config_group(item), struct fsg_lun_opts, group);
3139 static inline struct fsg_opts *to_fsg_opts(struct config_item *item)
3141 return container_of(to_config_group(item), struct fsg_opts,
3145 CONFIGFS_ATTR_STRUCT(fsg_lun_opts);
3146 CONFIGFS_ATTR_OPS(fsg_lun_opts);
3148 static void fsg_lun_attr_release(struct config_item *item)
3150 struct fsg_lun_opts *lun_opts;
3152 lun_opts = to_fsg_lun_opts(item);
3156 static struct configfs_item_operations fsg_lun_item_ops = {
3157 .release = fsg_lun_attr_release,
3158 .show_attribute = fsg_lun_opts_attr_show,
3159 .store_attribute = fsg_lun_opts_attr_store,
3162 static ssize_t fsg_lun_opts_file_show(struct fsg_lun_opts *opts, char *page)
3164 struct fsg_opts *fsg_opts;
3166 fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3168 return fsg_show_file(opts->lun, &fsg_opts->common->filesem, page);
3171 static ssize_t fsg_lun_opts_file_store(struct fsg_lun_opts *opts,
3172 const char *page, size_t len)
3174 struct fsg_opts *fsg_opts;
3176 fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3178 return fsg_store_file(opts->lun, &fsg_opts->common->filesem, page, len);
3181 static struct fsg_lun_opts_attribute fsg_lun_opts_file =
3182 __CONFIGFS_ATTR(file, S_IRUGO | S_IWUSR, fsg_lun_opts_file_show,
3183 fsg_lun_opts_file_store);
3185 static ssize_t fsg_lun_opts_ro_show(struct fsg_lun_opts *opts, char *page)
3187 return fsg_show_ro(opts->lun, page);
3190 static ssize_t fsg_lun_opts_ro_store(struct fsg_lun_opts *opts,
3191 const char *page, size_t len)
3193 struct fsg_opts *fsg_opts;
3195 fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3197 return fsg_store_ro(opts->lun, &fsg_opts->common->filesem, page, len);
3200 static struct fsg_lun_opts_attribute fsg_lun_opts_ro =
3201 __CONFIGFS_ATTR(ro, S_IRUGO | S_IWUSR, fsg_lun_opts_ro_show,
3202 fsg_lun_opts_ro_store);
3204 static ssize_t fsg_lun_opts_removable_show(struct fsg_lun_opts *opts,
3207 return fsg_show_removable(opts->lun, page);
3210 static ssize_t fsg_lun_opts_removable_store(struct fsg_lun_opts *opts,
3211 const char *page, size_t len)
3213 return fsg_store_removable(opts->lun, page, len);
3216 static struct fsg_lun_opts_attribute fsg_lun_opts_removable =
3217 __CONFIGFS_ATTR(removable, S_IRUGO | S_IWUSR,
3218 fsg_lun_opts_removable_show,
3219 fsg_lun_opts_removable_store);
3221 static ssize_t fsg_lun_opts_cdrom_show(struct fsg_lun_opts *opts, char *page)
3223 return fsg_show_cdrom(opts->lun, page);
3226 static ssize_t fsg_lun_opts_cdrom_store(struct fsg_lun_opts *opts,
3227 const char *page, size_t len)
3229 struct fsg_opts *fsg_opts;
3231 fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3233 return fsg_store_cdrom(opts->lun, &fsg_opts->common->filesem, page,
3237 static struct fsg_lun_opts_attribute fsg_lun_opts_cdrom =
3238 __CONFIGFS_ATTR(cdrom, S_IRUGO | S_IWUSR, fsg_lun_opts_cdrom_show,
3239 fsg_lun_opts_cdrom_store);
3241 static ssize_t fsg_lun_opts_nofua_show(struct fsg_lun_opts *opts, char *page)
3243 return fsg_show_nofua(opts->lun, page);
3246 static ssize_t fsg_lun_opts_nofua_store(struct fsg_lun_opts *opts,
3247 const char *page, size_t len)
3249 return fsg_store_nofua(opts->lun, page, len);
3252 static struct fsg_lun_opts_attribute fsg_lun_opts_nofua =
3253 __CONFIGFS_ATTR(nofua, S_IRUGO | S_IWUSR, fsg_lun_opts_nofua_show,
3254 fsg_lun_opts_nofua_store);
3256 static struct configfs_attribute *fsg_lun_attrs[] = {
3257 &fsg_lun_opts_file.attr,
3258 &fsg_lun_opts_ro.attr,
3259 &fsg_lun_opts_removable.attr,
3260 &fsg_lun_opts_cdrom.attr,
3261 &fsg_lun_opts_nofua.attr,
3265 static struct config_item_type fsg_lun_type = {
3266 .ct_item_ops = &fsg_lun_item_ops,
3267 .ct_attrs = fsg_lun_attrs,
3268 .ct_owner = THIS_MODULE,
3271 static struct config_group *fsg_lun_make(struct config_group *group,
3274 struct fsg_lun_opts *opts;
3275 struct fsg_opts *fsg_opts;
3276 struct fsg_lun_config config;
3281 num_str = strchr(name, '.');
3283 pr_err("Unable to locate . in LUN.NUMBER\n");
3284 return ERR_PTR(-EINVAL);
3288 ret = kstrtou8(num_str, 0, &num);
3290 return ERR_PTR(ret);
3292 fsg_opts = to_fsg_opts(&group->cg_item);
3293 if (num >= FSG_MAX_LUNS)
3294 return ERR_PTR(-ERANGE);
3296 mutex_lock(&fsg_opts->lock);
3297 if (fsg_opts->refcnt || fsg_opts->common->luns[num]) {
3302 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
3308 memset(&config, 0, sizeof(config));
3309 config.removable = true;
3311 ret = fsg_common_create_lun(fsg_opts->common, &config, num, name,
3312 (const char **)&group->cg_item.ci_name);
3317 opts->lun = fsg_opts->common->luns[num];
3319 mutex_unlock(&fsg_opts->lock);
3321 config_group_init_type_name(&opts->group, name, &fsg_lun_type);
3323 return &opts->group;
3325 mutex_unlock(&fsg_opts->lock);
3326 return ERR_PTR(ret);
3329 static void fsg_lun_drop(struct config_group *group, struct config_item *item)
3331 struct fsg_lun_opts *lun_opts;
3332 struct fsg_opts *fsg_opts;
3334 lun_opts = to_fsg_lun_opts(item);
3335 fsg_opts = to_fsg_opts(&group->cg_item);
3337 mutex_lock(&fsg_opts->lock);
3338 if (fsg_opts->refcnt) {
3339 struct config_item *gadget;
3341 gadget = group->cg_item.ci_parent->ci_parent;
3342 unregister_gadget_item(gadget);
3345 fsg_common_remove_lun(lun_opts->lun);
3346 fsg_opts->common->luns[lun_opts->lun_id] = NULL;
3347 lun_opts->lun_id = 0;
3348 mutex_unlock(&fsg_opts->lock);
3350 config_item_put(item);
3353 CONFIGFS_ATTR_STRUCT(fsg_opts);
3354 CONFIGFS_ATTR_OPS(fsg_opts);
3356 static void fsg_attr_release(struct config_item *item)
3358 struct fsg_opts *opts = to_fsg_opts(item);
3360 usb_put_function_instance(&opts->func_inst);
3363 static struct configfs_item_operations fsg_item_ops = {
3364 .release = fsg_attr_release,
3365 .show_attribute = fsg_opts_attr_show,
3366 .store_attribute = fsg_opts_attr_store,
3369 static ssize_t fsg_opts_stall_show(struct fsg_opts *opts, char *page)
3373 mutex_lock(&opts->lock);
3374 result = sprintf(page, "%d", opts->common->can_stall);
3375 mutex_unlock(&opts->lock);
3380 static ssize_t fsg_opts_stall_store(struct fsg_opts *opts, const char *page,
3386 mutex_lock(&opts->lock);
3389 mutex_unlock(&opts->lock);
3393 ret = strtobool(page, &stall);
3395 opts->common->can_stall = stall;
3399 mutex_unlock(&opts->lock);
3404 static struct fsg_opts_attribute fsg_opts_stall =
3405 __CONFIGFS_ATTR(stall, S_IRUGO | S_IWUSR, fsg_opts_stall_show,
3406 fsg_opts_stall_store);
3408 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
3409 static ssize_t fsg_opts_num_buffers_show(struct fsg_opts *opts, char *page)
3413 mutex_lock(&opts->lock);
3414 result = sprintf(page, "%d", opts->common->fsg_num_buffers);
3415 mutex_unlock(&opts->lock);
3420 static ssize_t fsg_opts_num_buffers_store(struct fsg_opts *opts,
3421 const char *page, size_t len)
3426 mutex_lock(&opts->lock);
3431 ret = kstrtou8(page, 0, &num);
3435 ret = fsg_num_buffers_validate(num);
3439 fsg_common_set_num_buffers(opts->common, num);
3443 mutex_unlock(&opts->lock);
3447 static struct fsg_opts_attribute fsg_opts_num_buffers =
3448 __CONFIGFS_ATTR(num_buffers, S_IRUGO | S_IWUSR,
3449 fsg_opts_num_buffers_show,
3450 fsg_opts_num_buffers_store);
3454 static struct configfs_attribute *fsg_attrs[] = {
3455 &fsg_opts_stall.attr,
3456 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
3457 &fsg_opts_num_buffers.attr,
3462 static struct configfs_group_operations fsg_group_ops = {
3463 .make_group = fsg_lun_make,
3464 .drop_item = fsg_lun_drop,
3467 static struct config_item_type fsg_func_type = {
3468 .ct_item_ops = &fsg_item_ops,
3469 .ct_group_ops = &fsg_group_ops,
3470 .ct_attrs = fsg_attrs,
3471 .ct_owner = THIS_MODULE,
3474 static void fsg_free_inst(struct usb_function_instance *fi)
3476 struct fsg_opts *opts;
3478 opts = fsg_opts_from_func_inst(fi);
3479 fsg_common_put(opts->common);
3483 static struct usb_function_instance *fsg_alloc_inst(void)
3485 struct fsg_opts *opts;
3486 struct fsg_lun_config config;
3489 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
3491 return ERR_PTR(-ENOMEM);
3492 mutex_init(&opts->lock);
3493 opts->func_inst.free_func_inst = fsg_free_inst;
3494 opts->common = fsg_common_setup(opts->common);
3495 if (IS_ERR(opts->common)) {
3496 rc = PTR_ERR(opts->common);
3500 rc = fsg_common_set_num_buffers(opts->common,
3501 CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS);
3505 pr_info(FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
3507 memset(&config, 0, sizeof(config));
3508 config.removable = true;
3509 rc = fsg_common_create_lun(opts->common, &config, 0, "lun.0",
3510 (const char **)&opts->func_inst.group.cg_item.ci_name);
3512 goto release_buffers;
3514 opts->lun0.lun = opts->common->luns[0];
3515 opts->lun0.lun_id = 0;
3516 config_group_init_type_name(&opts->lun0.group, "lun.0", &fsg_lun_type);
3517 opts->default_groups[0] = &opts->lun0.group;
3518 opts->func_inst.group.default_groups = opts->default_groups;
3520 config_group_init_type_name(&opts->func_inst.group, "", &fsg_func_type);
3522 return &opts->func_inst;
3525 fsg_common_free_buffers(opts->common);
3531 static void fsg_free(struct usb_function *f)
3533 struct fsg_dev *fsg;
3534 struct fsg_opts *opts;
3536 fsg = container_of(f, struct fsg_dev, function);
3537 opts = container_of(f->fi, struct fsg_opts, func_inst);
3539 mutex_lock(&opts->lock);
3541 mutex_unlock(&opts->lock);
3546 static struct usb_function *fsg_alloc(struct usb_function_instance *fi)
3548 struct fsg_opts *opts = fsg_opts_from_func_inst(fi);
3549 struct fsg_common *common = opts->common;
3550 struct fsg_dev *fsg;
3552 fsg = kzalloc(sizeof(*fsg), GFP_KERNEL);
3554 return ERR_PTR(-ENOMEM);
3556 mutex_lock(&opts->lock);
3558 mutex_unlock(&opts->lock);
3560 fsg->function.name = FSG_DRIVER_DESC;
3561 fsg->function.bind = fsg_bind;
3562 fsg->function.unbind = fsg_unbind;
3563 fsg->function.setup = fsg_setup;
3564 fsg->function.set_alt = fsg_set_alt;
3565 fsg->function.disable = fsg_disable;
3566 fsg->function.free_func = fsg_free;
3568 fsg->common = common;
3570 return &fsg->function;
3573 DECLARE_USB_FUNCTION_INIT(mass_storage, fsg_alloc_inst, fsg_alloc);
3574 MODULE_LICENSE("GPL");
3575 MODULE_AUTHOR("Michal Nazarewicz");
3577 /************************* Module parameters *************************/
3580 void fsg_config_from_params(struct fsg_config *cfg,
3581 const struct fsg_module_parameters *params,
3582 unsigned int fsg_num_buffers)
3584 struct fsg_lun_config *lun;
3587 /* Configure LUNs */
3589 min(params->luns ?: (params->file_count ?: 1u),
3590 (unsigned)FSG_MAX_LUNS);
3591 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3592 lun->ro = !!params->ro[i];
3593 lun->cdrom = !!params->cdrom[i];
3594 lun->removable = !!params->removable[i];
3596 params->file_count > i && params->file[i][0]
3601 /* Let MSF use defaults */
3602 cfg->vendor_name = NULL;
3603 cfg->product_name = NULL;
3606 cfg->private_data = NULL;
3609 cfg->can_stall = params->stall;
3610 cfg->fsg_num_buffers = fsg_num_buffers;
3612 EXPORT_SYMBOL_GPL(fsg_config_from_params);