1 // SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
3 * f_mass_storage.c -- Mass Storage USB Composite Function
5 * Copyright (C) 2003-2008 Alan Stern
6 * Copyright (C) 2009 Samsung Electronics
7 * Author: Michal Nazarewicz <mina86@mina86.com>
12 * The Mass Storage Function acts as a USB Mass Storage device,
13 * appearing to the host as a disk drive or as a CD-ROM drive. In
14 * addition to providing an example of a genuinely useful composite
15 * function for a USB device, it also illustrates a technique of
16 * double-buffering for increased throughput.
18 * For more information about MSF and in particular its module
19 * parameters and sysfs interface read the
20 * <Documentation/usb/mass-storage.rst> file.
24 * MSF is configured by specifying a fsg_config structure. It has the
27 * nluns Number of LUNs function have (anywhere from 1
29 * luns An array of LUN configuration values. This
30 * should be filled for each LUN that
31 * function will include (ie. for "nluns"
32 * LUNs). Each element of the array has
33 * the following fields:
34 * ->filename The path to the backing file for the LUN.
35 * Required if LUN is not marked as
37 * ->ro Flag specifying access to the LUN shall be
38 * read-only. This is implied if CD-ROM
39 * emulation is enabled as well as when
40 * it was impossible to open "filename"
42 * ->removable Flag specifying that LUN shall be indicated as
44 * ->cdrom Flag specifying that LUN shall be reported as
46 * ->nofua Flag specifying that FUA flag in SCSI WRITE(10,12)
47 * commands for this LUN shall be ignored.
51 * release Information used as a reply to INQUIRY
52 * request. To use default set to NULL,
53 * NULL, 0xffff respectively. The first
54 * field should be 8 and the second 16
57 * can_stall Set to permit function to halt bulk endpoints.
58 * Disabled on some USB devices known not
59 * to work correctly. You should set it
62 * If "removable" is not set for a LUN then a backing file must be
63 * specified. If it is set, then NULL filename means the LUN's medium
64 * is not loaded (an empty string as "filename" in the fsg_config
65 * structure causes error). The CD-ROM emulation includes a single
66 * data track and no audio tracks; hence there need be only one
67 * backing file per LUN.
69 * This function is heavily based on "File-backed Storage Gadget" by
70 * Alan Stern which in turn is heavily based on "Gadget Zero" by David
71 * Brownell. The driver's SCSI command interface was based on the
72 * "Information technology - Small Computer System Interface - 2"
73 * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
74 * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
75 * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
76 * was based on the "Universal Serial Bus Mass Storage Class UFI
77 * Command Specification" document, Revision 1.0, December 14, 1998,
79 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
85 * The MSF is fairly straightforward. There is a main kernel
86 * thread that handles most of the work. Interrupt routines field
87 * callbacks from the controller driver: bulk- and interrupt-request
88 * completion notifications, endpoint-0 events, and disconnect events.
89 * Completion events are passed to the main thread by wakeup calls. Many
90 * ep0 requests are handled at interrupt time, but SetInterface,
91 * SetConfiguration, and device reset requests are forwarded to the
92 * thread in the form of "exceptions" using SIGUSR1 signals (since they
93 * should interrupt any ongoing file I/O operations).
95 * The thread's main routine implements the standard command/data/status
96 * parts of a SCSI interaction. It and its subroutines are full of tests
97 * for pending signals/exceptions -- all this polling is necessary since
98 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
99 * indication that the driver really wants to be running in userspace.)
100 * An important point is that so long as the thread is alive it keeps an
101 * open reference to the backing file. This will prevent unmounting
102 * the backing file's underlying filesystem and could cause problems
103 * during system shutdown, for example. To prevent such problems, the
104 * thread catches INT, TERM, and KILL signals and converts them into
107 * In normal operation the main thread is started during the gadget's
108 * fsg_bind() callback and stopped during fsg_unbind(). But it can
109 * also exit when it receives a signal, and there's no point leaving
110 * the gadget running when the thread is dead. As of this moment, MSF
111 * provides no way to deregister the gadget when thread dies -- maybe
112 * a callback functions is needed.
114 * To provide maximum throughput, the driver uses a circular pipeline of
115 * buffer heads (struct fsg_buffhd). In principle the pipeline can be
116 * arbitrarily long; in practice the benefits don't justify having more
117 * than 2 stages (i.e., double buffering). But it helps to think of the
118 * pipeline as being a long one. Each buffer head contains a bulk-in and
119 * a bulk-out request pointer (since the buffer can be used for both
120 * output and input -- directions always are given from the host's
121 * point of view) as well as a pointer to the buffer and various state
124 * Use of the pipeline follows a simple protocol. There is a variable
125 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
126 * At any time that buffer head may still be in use from an earlier
127 * request, so each buffer head has a state variable indicating whether
128 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
129 * buffer head to be EMPTY, filling the buffer either by file I/O or by
130 * USB I/O (during which the buffer head is BUSY), and marking the buffer
131 * head FULL when the I/O is complete. Then the buffer will be emptied
132 * (again possibly by USB I/O, during which it is marked BUSY) and
133 * finally marked EMPTY again (possibly by a completion routine).
135 * A module parameter tells the driver to avoid stalling the bulk
136 * endpoints wherever the transport specification allows. This is
137 * necessary for some UDCs like the SuperH, which cannot reliably clear a
138 * halt on a bulk endpoint. However, under certain circumstances the
139 * Bulk-only specification requires a stall. In such cases the driver
140 * will halt the endpoint and set a flag indicating that it should clear
141 * the halt in software during the next device reset. Hopefully this
142 * will permit everything to work correctly. Furthermore, although the
143 * specification allows the bulk-out endpoint to halt when the host sends
144 * too much data, implementing this would cause an unavoidable race.
145 * The driver will always use the "no-stall" approach for OUT transfers.
147 * One subtle point concerns sending status-stage responses for ep0
148 * requests. Some of these requests, such as device reset, can involve
149 * interrupting an ongoing file I/O operation, which might take an
150 * arbitrarily long time. During that delay the host might give up on
151 * the original ep0 request and issue a new one. When that happens the
152 * driver should not notify the host about completion of the original
153 * request, as the host will no longer be waiting for it. So the driver
154 * assigns to each ep0 request a unique tag, and it keeps track of the
155 * tag value of the request associated with a long-running exception
156 * (device-reset, interface-change, or configuration-change). When the
157 * exception handler is finished, the status-stage response is submitted
158 * only if the current ep0 request tag is equal to the exception request
159 * tag. Thus only the most recently received ep0 request will get a
160 * status-stage response.
162 * Warning: This driver source file is too long. It ought to be split up
163 * into a header file plus about 3 separate .c files, to handle the details
164 * of the Gadget, USB Mass Storage, and SCSI protocols.
168 /* #define VERBOSE_DEBUG */
169 /* #define DUMP_MSGS */
171 #include <linux/blkdev.h>
172 #include <linux/completion.h>
173 #include <linux/dcache.h>
174 #include <linux/delay.h>
175 #include <linux/device.h>
176 #include <linux/fcntl.h>
177 #include <linux/file.h>
178 #include <linux/fs.h>
179 #include <linux/kthread.h>
180 #include <linux/sched/signal.h>
181 #include <linux/limits.h>
182 #include <linux/pagemap.h>
183 #include <linux/rwsem.h>
184 #include <linux/slab.h>
185 #include <linux/spinlock.h>
186 #include <linux/string.h>
187 #include <linux/freezer.h>
188 #include <linux/module.h>
189 #include <linux/uaccess.h>
190 #include <asm/unaligned.h>
192 #include <linux/usb/ch9.h>
193 #include <linux/usb/gadget.h>
194 #include <linux/usb/composite.h>
196 #include <linux/nospec.h>
198 #include "configfs.h"
201 /*------------------------------------------------------------------------*/
203 #define FSG_DRIVER_DESC "Mass Storage Function"
204 #define FSG_DRIVER_VERSION "2009/09/11"
206 static const char fsg_string_interface[] = "Mass Storage";
208 #include "storage_common.h"
209 #include "f_mass_storage.h"
211 /* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
212 static struct usb_string fsg_strings[] = {
213 {FSG_STRING_INTERFACE, fsg_string_interface},
217 static struct usb_gadget_strings fsg_stringtab = {
218 .language = 0x0409, /* en-us */
219 .strings = fsg_strings,
222 static struct usb_gadget_strings *fsg_strings_array[] = {
227 /*-------------------------------------------------------------------------*/
232 /* Data shared by all the FSG instances. */
234 struct usb_gadget *gadget;
235 struct usb_composite_dev *cdev;
237 wait_queue_head_t io_wait;
238 wait_queue_head_t fsg_wait;
240 /* filesem protects: backing files in use */
241 struct rw_semaphore filesem;
243 /* lock protects: state and thread_task */
246 struct usb_ep *ep0; /* Copy of gadget->ep0 */
247 struct usb_request *ep0req; /* Copy of cdev->req */
248 unsigned int ep0_req_tag;
250 struct fsg_buffhd *next_buffhd_to_fill;
251 struct fsg_buffhd *next_buffhd_to_drain;
252 struct fsg_buffhd *buffhds;
253 unsigned int fsg_num_buffers;
256 u8 cmnd[MAX_COMMAND_SIZE];
259 struct fsg_lun *luns[FSG_MAX_LUNS];
260 struct fsg_lun *curlun;
262 unsigned int bulk_out_maxpacket;
263 enum fsg_state state; /* For exception handling */
264 unsigned int exception_req_tag;
267 enum data_direction data_dir;
269 u32 data_size_from_cmnd;
274 unsigned int can_stall:1;
275 unsigned int free_storage_on_release:1;
276 unsigned int phase_error:1;
277 unsigned int short_packet_received:1;
278 unsigned int bad_lun_okay:1;
279 unsigned int running:1;
280 unsigned int sysfs:1;
282 struct completion thread_notifier;
283 struct task_struct *thread_task;
285 /* Gadget's private data. */
288 char inquiry_string[INQUIRY_STRING_LEN];
292 struct usb_function function;
293 struct usb_gadget *gadget; /* Copy of cdev->gadget */
294 struct fsg_common *common;
296 u16 interface_number;
298 unsigned int bulk_in_enabled:1;
299 unsigned int bulk_out_enabled:1;
301 unsigned long atomic_bitflags;
302 #define IGNORE_BULK_OUT 0
304 struct usb_ep *bulk_in;
305 struct usb_ep *bulk_out;
308 static inline int __fsg_is_set(struct fsg_common *common,
309 const char *func, unsigned line)
313 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
318 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
320 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
322 return container_of(f, struct fsg_dev, function);
325 static int exception_in_progress(struct fsg_common *common)
327 return common->state > FSG_STATE_NORMAL;
330 /* Make bulk-out requests be divisible by the maxpacket size */
331 static void set_bulk_out_req_length(struct fsg_common *common,
332 struct fsg_buffhd *bh, unsigned int length)
336 bh->bulk_out_intended_length = length;
337 rem = length % common->bulk_out_maxpacket;
339 length += common->bulk_out_maxpacket - rem;
340 bh->outreq->length = length;
344 /*-------------------------------------------------------------------------*/
346 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
350 if (ep == fsg->bulk_in)
352 else if (ep == fsg->bulk_out)
356 DBG(fsg, "%s set halt\n", name);
357 return usb_ep_set_halt(ep);
361 /*-------------------------------------------------------------------------*/
363 /* These routines may be called in process context or in_irq */
365 static void __raise_exception(struct fsg_common *common, enum fsg_state new_state,
371 * Do nothing if a higher-priority exception is already in progress.
372 * If a lower-or-equal priority exception is in progress, preempt it
373 * and notify the main thread by sending it a signal.
375 spin_lock_irqsave(&common->lock, flags);
376 if (common->state <= new_state) {
377 common->exception_req_tag = common->ep0_req_tag;
378 common->state = new_state;
379 common->exception_arg = arg;
380 if (common->thread_task)
381 send_sig_info(SIGUSR1, SEND_SIG_PRIV,
382 common->thread_task);
384 spin_unlock_irqrestore(&common->lock, flags);
387 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
389 __raise_exception(common, new_state, NULL);
392 /*-------------------------------------------------------------------------*/
394 static int ep0_queue(struct fsg_common *common)
398 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
399 common->ep0->driver_data = common;
400 if (rc != 0 && rc != -ESHUTDOWN) {
401 /* We can't do much more than wait for a reset */
402 WARNING(common, "error in submission: %s --> %d\n",
403 common->ep0->name, rc);
409 /*-------------------------------------------------------------------------*/
411 /* Completion handlers. These always run in_irq. */
413 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
415 struct fsg_common *common = ep->driver_data;
416 struct fsg_buffhd *bh = req->context;
418 if (req->status || req->actual != req->length)
419 DBG(common, "%s --> %d, %u/%u\n", __func__,
420 req->status, req->actual, req->length);
421 if (req->status == -ECONNRESET) /* Request was cancelled */
422 usb_ep_fifo_flush(ep);
424 /* Synchronize with the smp_load_acquire() in sleep_thread() */
425 smp_store_release(&bh->state, BUF_STATE_EMPTY);
426 wake_up(&common->io_wait);
429 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
431 struct fsg_common *common = ep->driver_data;
432 struct fsg_buffhd *bh = req->context;
434 dump_msg(common, "bulk-out", req->buf, req->actual);
435 if (req->status || req->actual != bh->bulk_out_intended_length)
436 DBG(common, "%s --> %d, %u/%u\n", __func__,
437 req->status, req->actual, bh->bulk_out_intended_length);
438 if (req->status == -ECONNRESET) /* Request was cancelled */
439 usb_ep_fifo_flush(ep);
441 /* Synchronize with the smp_load_acquire() in sleep_thread() */
442 smp_store_release(&bh->state, BUF_STATE_FULL);
443 wake_up(&common->io_wait);
446 static int _fsg_common_get_max_lun(struct fsg_common *common)
448 int i = ARRAY_SIZE(common->luns) - 1;
450 while (i >= 0 && !common->luns[i])
456 static int fsg_setup(struct usb_function *f,
457 const struct usb_ctrlrequest *ctrl)
459 struct fsg_dev *fsg = fsg_from_func(f);
460 struct usb_request *req = fsg->common->ep0req;
461 u16 w_index = le16_to_cpu(ctrl->wIndex);
462 u16 w_value = le16_to_cpu(ctrl->wValue);
463 u16 w_length = le16_to_cpu(ctrl->wLength);
465 if (!fsg_is_set(fsg->common))
468 ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
471 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
473 switch (ctrl->bRequest) {
475 case US_BULK_RESET_REQUEST:
476 if (ctrl->bRequestType !=
477 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
479 if (w_index != fsg->interface_number || w_value != 0 ||
484 * Raise an exception to stop the current operation
485 * and reinitialize our state.
487 DBG(fsg, "bulk reset request\n");
488 raise_exception(fsg->common, FSG_STATE_PROTOCOL_RESET);
489 return USB_GADGET_DELAYED_STATUS;
491 case US_BULK_GET_MAX_LUN:
492 if (ctrl->bRequestType !=
493 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
495 if (w_index != fsg->interface_number || w_value != 0 ||
498 VDBG(fsg, "get max LUN\n");
499 *(u8 *)req->buf = _fsg_common_get_max_lun(fsg->common);
501 /* Respond with data/status */
502 req->length = min((u16)1, w_length);
503 return ep0_queue(fsg->common);
507 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
508 ctrl->bRequestType, ctrl->bRequest,
509 le16_to_cpu(ctrl->wValue), w_index, w_length);
514 /*-------------------------------------------------------------------------*/
516 /* All the following routines run in process context */
518 /* Use this for bulk or interrupt transfers, not ep0 */
519 static int start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
520 struct usb_request *req)
524 if (ep == fsg->bulk_in)
525 dump_msg(fsg, "bulk-in", req->buf, req->length);
527 rc = usb_ep_queue(ep, req, GFP_KERNEL);
530 /* We can't do much more than wait for a reset */
534 * Note: currently the net2280 driver fails zero-length
535 * submissions if DMA is enabled.
537 if (rc != -ESHUTDOWN &&
538 !(rc == -EOPNOTSUPP && req->length == 0))
539 WARNING(fsg, "error in submission: %s --> %d\n",
545 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
547 if (!fsg_is_set(common))
549 bh->state = BUF_STATE_SENDING;
550 if (start_transfer(common->fsg, common->fsg->bulk_in, bh->inreq))
551 bh->state = BUF_STATE_EMPTY;
555 static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
557 if (!fsg_is_set(common))
559 bh->state = BUF_STATE_RECEIVING;
560 if (start_transfer(common->fsg, common->fsg->bulk_out, bh->outreq))
561 bh->state = BUF_STATE_FULL;
565 static int sleep_thread(struct fsg_common *common, bool can_freeze,
566 struct fsg_buffhd *bh)
570 /* Wait until a signal arrives or bh is no longer busy */
573 * synchronize with the smp_store_release(&bh->state) in
574 * bulk_in_complete() or bulk_out_complete()
576 rc = wait_event_freezable(common->io_wait,
577 bh && smp_load_acquire(&bh->state) >=
580 rc = wait_event_interruptible(common->io_wait,
581 bh && smp_load_acquire(&bh->state) >=
583 return rc ? -EINTR : 0;
587 /*-------------------------------------------------------------------------*/
589 static int do_read(struct fsg_common *common)
591 struct fsg_lun *curlun = common->curlun;
593 struct fsg_buffhd *bh;
596 loff_t file_offset, file_offset_tmp;
601 * Get the starting Logical Block Address and check that it's
604 if (common->cmnd[0] == READ_6)
605 lba = get_unaligned_be24(&common->cmnd[1]);
607 if (common->cmnd[0] == READ_16)
608 lba = get_unaligned_be64(&common->cmnd[2]);
609 else /* READ_10 or READ_12 */
610 lba = get_unaligned_be32(&common->cmnd[2]);
613 * We allow DPO (Disable Page Out = don't save data in the
614 * cache) and FUA (Force Unit Access = don't read from the
615 * cache), but we don't implement them.
617 if ((common->cmnd[1] & ~0x18) != 0) {
618 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
622 if (lba >= curlun->num_sectors) {
623 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
626 file_offset = ((loff_t) lba) << curlun->blkbits;
628 /* Carry out the file reads */
629 amount_left = common->data_size_from_cmnd;
630 if (unlikely(amount_left == 0))
631 return -EIO; /* No default reply */
635 * Figure out how much we need to read:
636 * Try to read the remaining amount.
637 * But don't read more than the buffer size.
638 * And don't try to read past the end of the file.
640 amount = min(amount_left, FSG_BUFLEN);
641 amount = min((loff_t)amount,
642 curlun->file_length - file_offset);
644 /* Wait for the next buffer to become available */
645 bh = common->next_buffhd_to_fill;
646 rc = sleep_thread(common, false, bh);
651 * If we were asked to read past the end of file,
652 * end with an empty buffer.
656 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
657 curlun->sense_data_info =
658 file_offset >> curlun->blkbits;
659 curlun->info_valid = 1;
660 bh->inreq->length = 0;
661 bh->state = BUF_STATE_FULL;
665 /* Perform the read */
666 file_offset_tmp = file_offset;
667 nread = kernel_read(curlun->filp, bh->buf, amount,
669 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
670 (unsigned long long)file_offset, (int)nread);
671 if (signal_pending(current))
675 LDBG(curlun, "error in file read: %d\n", (int)nread);
677 } else if (nread < amount) {
678 LDBG(curlun, "partial file read: %d/%u\n",
680 nread = round_down(nread, curlun->blksize);
682 file_offset += nread;
683 amount_left -= nread;
684 common->residue -= nread;
687 * Except at the end of the transfer, nread will be
688 * equal to the buffer size, which is divisible by the
689 * bulk-in maxpacket size.
691 bh->inreq->length = nread;
692 bh->state = BUF_STATE_FULL;
694 /* If an error occurred, report it and its position */
695 if (nread < amount) {
696 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
697 curlun->sense_data_info =
698 file_offset >> curlun->blkbits;
699 curlun->info_valid = 1;
703 if (amount_left == 0)
704 break; /* No more left to read */
706 /* Send this buffer and go read some more */
708 if (!start_in_transfer(common, bh))
709 /* Don't know what to do if common->fsg is NULL */
711 common->next_buffhd_to_fill = bh->next;
714 return -EIO; /* No default reply */
718 /*-------------------------------------------------------------------------*/
720 static int do_write(struct fsg_common *common)
722 struct fsg_lun *curlun = common->curlun;
724 struct fsg_buffhd *bh;
726 u32 amount_left_to_req, amount_left_to_write;
727 loff_t usb_offset, file_offset, file_offset_tmp;
733 curlun->sense_data = SS_WRITE_PROTECTED;
736 spin_lock(&curlun->filp->f_lock);
737 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
738 spin_unlock(&curlun->filp->f_lock);
741 * Get the starting Logical Block Address and check that it's
744 if (common->cmnd[0] == WRITE_6)
745 lba = get_unaligned_be24(&common->cmnd[1]);
747 if (common->cmnd[0] == WRITE_16)
748 lba = get_unaligned_be64(&common->cmnd[2]);
749 else /* WRITE_10 or WRITE_12 */
750 lba = get_unaligned_be32(&common->cmnd[2]);
753 * We allow DPO (Disable Page Out = don't save data in the
754 * cache) and FUA (Force Unit Access = write directly to the
755 * medium). We don't implement DPO; we implement FUA by
756 * performing synchronous output.
758 if (common->cmnd[1] & ~0x18) {
759 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
762 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
763 spin_lock(&curlun->filp->f_lock);
764 curlun->filp->f_flags |= O_SYNC;
765 spin_unlock(&curlun->filp->f_lock);
768 if (lba >= curlun->num_sectors) {
769 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
773 /* Carry out the file writes */
775 file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
776 amount_left_to_req = common->data_size_from_cmnd;
777 amount_left_to_write = common->data_size_from_cmnd;
779 while (amount_left_to_write > 0) {
781 /* Queue a request for more data from the host */
782 bh = common->next_buffhd_to_fill;
783 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
786 * Figure out how much we want to get:
787 * Try to get the remaining amount,
788 * but not more than the buffer size.
790 amount = min(amount_left_to_req, FSG_BUFLEN);
792 /* Beyond the end of the backing file? */
793 if (usb_offset >= curlun->file_length) {
796 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
797 curlun->sense_data_info =
798 usb_offset >> curlun->blkbits;
799 curlun->info_valid = 1;
803 /* Get the next buffer */
804 usb_offset += amount;
805 common->usb_amount_left -= amount;
806 amount_left_to_req -= amount;
807 if (amount_left_to_req == 0)
811 * Except at the end of the transfer, amount will be
812 * equal to the buffer size, which is divisible by
813 * the bulk-out maxpacket size.
815 set_bulk_out_req_length(common, bh, amount);
816 if (!start_out_transfer(common, bh))
817 /* Dunno what to do if common->fsg is NULL */
819 common->next_buffhd_to_fill = bh->next;
823 /* Write the received data to the backing file */
824 bh = common->next_buffhd_to_drain;
825 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
826 break; /* We stopped early */
828 /* Wait for the data to be received */
829 rc = sleep_thread(common, false, bh);
833 common->next_buffhd_to_drain = bh->next;
834 bh->state = BUF_STATE_EMPTY;
836 /* Did something go wrong with the transfer? */
837 if (bh->outreq->status != 0) {
838 curlun->sense_data = SS_COMMUNICATION_FAILURE;
839 curlun->sense_data_info =
840 file_offset >> curlun->blkbits;
841 curlun->info_valid = 1;
845 amount = bh->outreq->actual;
846 if (curlun->file_length - file_offset < amount) {
847 LERROR(curlun, "write %u @ %llu beyond end %llu\n",
848 amount, (unsigned long long)file_offset,
849 (unsigned long long)curlun->file_length);
850 amount = curlun->file_length - file_offset;
854 * Don't accept excess data. The spec doesn't say
855 * what to do in this case. We'll ignore the error.
857 amount = min(amount, bh->bulk_out_intended_length);
859 /* Don't write a partial block */
860 amount = round_down(amount, curlun->blksize);
864 /* Perform the write */
865 file_offset_tmp = file_offset;
866 nwritten = kernel_write(curlun->filp, bh->buf, amount,
868 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
869 (unsigned long long)file_offset, (int)nwritten);
870 if (signal_pending(current))
871 return -EINTR; /* Interrupted! */
874 LDBG(curlun, "error in file write: %d\n",
877 } else if (nwritten < amount) {
878 LDBG(curlun, "partial file write: %d/%u\n",
879 (int) nwritten, amount);
880 nwritten = round_down(nwritten, curlun->blksize);
882 file_offset += nwritten;
883 amount_left_to_write -= nwritten;
884 common->residue -= nwritten;
886 /* If an error occurred, report it and its position */
887 if (nwritten < amount) {
888 curlun->sense_data = SS_WRITE_ERROR;
889 curlun->sense_data_info =
890 file_offset >> curlun->blkbits;
891 curlun->info_valid = 1;
896 /* Did the host decide to stop early? */
897 if (bh->outreq->actual < bh->bulk_out_intended_length) {
898 common->short_packet_received = 1;
903 return -EIO; /* No default reply */
907 /*-------------------------------------------------------------------------*/
909 static int do_synchronize_cache(struct fsg_common *common)
911 struct fsg_lun *curlun = common->curlun;
914 /* We ignore the requested LBA and write out all file's
915 * dirty data buffers. */
916 rc = fsg_lun_fsync_sub(curlun);
918 curlun->sense_data = SS_WRITE_ERROR;
923 /*-------------------------------------------------------------------------*/
925 static void invalidate_sub(struct fsg_lun *curlun)
927 struct file *filp = curlun->filp;
928 struct inode *inode = file_inode(filp);
931 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
932 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
935 static int do_verify(struct fsg_common *common)
937 struct fsg_lun *curlun = common->curlun;
939 u32 verification_length;
940 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
941 loff_t file_offset, file_offset_tmp;
947 * Get the starting Logical Block Address and check that it's
950 lba = get_unaligned_be32(&common->cmnd[2]);
951 if (lba >= curlun->num_sectors) {
952 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
957 * We allow DPO (Disable Page Out = don't save data in the
958 * cache) but we don't implement it.
960 if (common->cmnd[1] & ~0x10) {
961 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
965 verification_length = get_unaligned_be16(&common->cmnd[7]);
966 if (unlikely(verification_length == 0))
967 return -EIO; /* No default reply */
969 /* Prepare to carry out the file verify */
970 amount_left = verification_length << curlun->blkbits;
971 file_offset = ((loff_t) lba) << curlun->blkbits;
973 /* Write out all the dirty buffers before invalidating them */
974 fsg_lun_fsync_sub(curlun);
975 if (signal_pending(current))
978 invalidate_sub(curlun);
979 if (signal_pending(current))
982 /* Just try to read the requested blocks */
983 while (amount_left > 0) {
985 * Figure out how much we need to read:
986 * Try to read the remaining amount, but not more than
988 * And don't try to read past the end of the file.
990 amount = min(amount_left, FSG_BUFLEN);
991 amount = min((loff_t)amount,
992 curlun->file_length - file_offset);
995 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
996 curlun->sense_data_info =
997 file_offset >> curlun->blkbits;
998 curlun->info_valid = 1;
1002 /* Perform the read */
1003 file_offset_tmp = file_offset;
1004 nread = kernel_read(curlun->filp, bh->buf, amount,
1006 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1007 (unsigned long long) file_offset,
1009 if (signal_pending(current))
1013 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1015 } else if (nread < amount) {
1016 LDBG(curlun, "partial file verify: %d/%u\n",
1017 (int)nread, amount);
1018 nread = round_down(nread, curlun->blksize);
1021 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1022 curlun->sense_data_info =
1023 file_offset >> curlun->blkbits;
1024 curlun->info_valid = 1;
1027 file_offset += nread;
1028 amount_left -= nread;
1034 /*-------------------------------------------------------------------------*/
1036 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1038 struct fsg_lun *curlun = common->curlun;
1039 u8 *buf = (u8 *) bh->buf;
1041 if (!curlun) { /* Unsupported LUNs are okay */
1042 common->bad_lun_okay = 1;
1044 buf[0] = TYPE_NO_LUN; /* Unsupported, no device-type */
1045 buf[4] = 31; /* Additional length */
1049 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1050 buf[1] = curlun->removable ? 0x80 : 0;
1051 buf[2] = 2; /* ANSI SCSI level 2 */
1052 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1053 buf[4] = 31; /* Additional length */
1054 buf[5] = 0; /* No special options */
1057 if (curlun->inquiry_string[0])
1058 memcpy(buf + 8, curlun->inquiry_string,
1059 sizeof(curlun->inquiry_string));
1061 memcpy(buf + 8, common->inquiry_string,
1062 sizeof(common->inquiry_string));
1066 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1068 struct fsg_lun *curlun = common->curlun;
1069 u8 *buf = (u8 *) bh->buf;
1074 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1076 * If a REQUEST SENSE command is received from an initiator
1077 * with a pending unit attention condition (before the target
1078 * generates the contingent allegiance condition), then the
1079 * target shall either:
1080 * a) report any pending sense data and preserve the unit
1081 * attention condition on the logical unit, or,
1082 * b) report the unit attention condition, may discard any
1083 * pending sense data, and clear the unit attention
1084 * condition on the logical unit for that initiator.
1086 * FSG normally uses option a); enable this code to use option b).
1089 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1090 curlun->sense_data = curlun->unit_attention_data;
1091 curlun->unit_attention_data = SS_NO_SENSE;
1095 if (!curlun) { /* Unsupported LUNs are okay */
1096 common->bad_lun_okay = 1;
1097 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1101 sd = curlun->sense_data;
1102 sdinfo = curlun->sense_data_info;
1103 valid = curlun->info_valid << 7;
1104 curlun->sense_data = SS_NO_SENSE;
1105 curlun->sense_data_info = 0;
1106 curlun->info_valid = 0;
1110 buf[0] = valid | 0x70; /* Valid, current error */
1112 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1113 buf[7] = 18 - 8; /* Additional sense length */
1119 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1121 struct fsg_lun *curlun = common->curlun;
1122 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1123 int pmi = common->cmnd[8];
1124 u8 *buf = (u8 *)bh->buf;
1127 /* Check the PMI and LBA fields */
1128 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1129 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1133 if (curlun->num_sectors < 0x100000000ULL)
1134 max_lba = curlun->num_sectors - 1;
1136 max_lba = 0xffffffff;
1137 put_unaligned_be32(max_lba, &buf[0]); /* Max logical block */
1138 put_unaligned_be32(curlun->blksize, &buf[4]); /* Block length */
1142 static int do_read_capacity_16(struct fsg_common *common, struct fsg_buffhd *bh)
1144 struct fsg_lun *curlun = common->curlun;
1145 u64 lba = get_unaligned_be64(&common->cmnd[2]);
1146 int pmi = common->cmnd[14];
1147 u8 *buf = (u8 *)bh->buf;
1149 /* Check the PMI and LBA fields */
1150 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1151 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1155 put_unaligned_be64(curlun->num_sectors - 1, &buf[0]);
1156 /* Max logical block */
1157 put_unaligned_be32(curlun->blksize, &buf[8]); /* Block length */
1159 /* It is safe to keep other fields zeroed */
1160 memset(&buf[12], 0, 32 - 12);
1164 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1166 struct fsg_lun *curlun = common->curlun;
1167 int msf = common->cmnd[1] & 0x02;
1168 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1169 u8 *buf = (u8 *)bh->buf;
1171 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1172 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1175 if (lba >= curlun->num_sectors) {
1176 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1181 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1182 store_cdrom_address(&buf[4], msf, lba);
1186 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1188 struct fsg_lun *curlun = common->curlun;
1189 int msf = common->cmnd[1] & 0x02;
1190 int start_track = common->cmnd[6];
1191 u8 *buf = (u8 *)bh->buf;
1193 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1195 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1200 buf[1] = (20-2); /* TOC data length */
1201 buf[2] = 1; /* First track number */
1202 buf[3] = 1; /* Last track number */
1203 buf[5] = 0x16; /* Data track, copying allowed */
1204 buf[6] = 0x01; /* Only track is number 1 */
1205 store_cdrom_address(&buf[8], msf, 0);
1207 buf[13] = 0x16; /* Lead-out track is data */
1208 buf[14] = 0xAA; /* Lead-out track number */
1209 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1213 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1215 struct fsg_lun *curlun = common->curlun;
1216 int mscmnd = common->cmnd[0];
1217 u8 *buf = (u8 *) bh->buf;
1220 int changeable_values, all_pages;
1224 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1225 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1228 pc = common->cmnd[2] >> 6;
1229 page_code = common->cmnd[2] & 0x3f;
1231 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1234 changeable_values = (pc == 1);
1235 all_pages = (page_code == 0x3f);
1238 * Write the mode parameter header. Fixed values are: default
1239 * medium type, no cache control (DPOFUA), and no block descriptors.
1240 * The only variable value is the WriteProtect bit. We will fill in
1241 * the mode data length later.
1244 if (mscmnd == MODE_SENSE) {
1245 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1248 } else { /* MODE_SENSE_10 */
1249 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1251 limit = 65535; /* Should really be FSG_BUFLEN */
1254 /* No block descriptors */
1257 * The mode pages, in numerical order. The only page we support
1258 * is the Caching page.
1260 if (page_code == 0x08 || all_pages) {
1262 buf[0] = 0x08; /* Page code */
1263 buf[1] = 10; /* Page length */
1264 memset(buf+2, 0, 10); /* None of the fields are changeable */
1266 if (!changeable_values) {
1267 buf[2] = 0x04; /* Write cache enable, */
1268 /* Read cache not disabled */
1269 /* No cache retention priorities */
1270 put_unaligned_be16(0xffff, &buf[4]);
1271 /* Don't disable prefetch */
1272 /* Minimum prefetch = 0 */
1273 put_unaligned_be16(0xffff, &buf[8]);
1274 /* Maximum prefetch */
1275 put_unaligned_be16(0xffff, &buf[10]);
1276 /* Maximum prefetch ceiling */
1282 * Check that a valid page was requested and the mode data length
1286 if (!valid_page || len > limit) {
1287 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1291 /* Store the mode data length */
1292 if (mscmnd == MODE_SENSE)
1295 put_unaligned_be16(len - 2, buf0);
1299 static int do_start_stop(struct fsg_common *common)
1301 struct fsg_lun *curlun = common->curlun;
1306 } else if (!curlun->removable) {
1307 curlun->sense_data = SS_INVALID_COMMAND;
1309 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1310 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1311 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1315 loej = common->cmnd[4] & 0x02;
1316 start = common->cmnd[4] & 0x01;
1319 * Our emulation doesn't support mounting; the medium is
1320 * available for use as soon as it is loaded.
1323 if (!fsg_lun_is_open(curlun)) {
1324 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1330 /* Are we allowed to unload the media? */
1331 if (curlun->prevent_medium_removal) {
1332 LDBG(curlun, "unload attempt prevented\n");
1333 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1340 up_read(&common->filesem);
1341 down_write(&common->filesem);
1342 fsg_lun_close(curlun);
1343 up_write(&common->filesem);
1344 down_read(&common->filesem);
1349 static int do_prevent_allow(struct fsg_common *common)
1351 struct fsg_lun *curlun = common->curlun;
1354 if (!common->curlun) {
1356 } else if (!common->curlun->removable) {
1357 common->curlun->sense_data = SS_INVALID_COMMAND;
1361 prevent = common->cmnd[4] & 0x01;
1362 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1363 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1367 if (curlun->prevent_medium_removal && !prevent)
1368 fsg_lun_fsync_sub(curlun);
1369 curlun->prevent_medium_removal = prevent;
1373 static int do_read_format_capacities(struct fsg_common *common,
1374 struct fsg_buffhd *bh)
1376 struct fsg_lun *curlun = common->curlun;
1377 u8 *buf = (u8 *) bh->buf;
1379 buf[0] = buf[1] = buf[2] = 0;
1380 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1383 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1384 /* Number of blocks */
1385 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1386 buf[4] = 0x02; /* Current capacity */
1390 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1392 struct fsg_lun *curlun = common->curlun;
1394 /* We don't support MODE SELECT */
1396 curlun->sense_data = SS_INVALID_COMMAND;
1401 /*-------------------------------------------------------------------------*/
1403 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1407 rc = fsg_set_halt(fsg, fsg->bulk_in);
1409 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1411 if (rc != -EAGAIN) {
1412 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1417 /* Wait for a short time and then try again */
1418 if (msleep_interruptible(100) != 0)
1420 rc = usb_ep_set_halt(fsg->bulk_in);
1425 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1429 DBG(fsg, "bulk-in set wedge\n");
1430 rc = usb_ep_set_wedge(fsg->bulk_in);
1432 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1434 if (rc != -EAGAIN) {
1435 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1440 /* Wait for a short time and then try again */
1441 if (msleep_interruptible(100) != 0)
1443 rc = usb_ep_set_wedge(fsg->bulk_in);
1448 static int throw_away_data(struct fsg_common *common)
1450 struct fsg_buffhd *bh, *bh2;
1454 for (bh = common->next_buffhd_to_drain;
1455 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1456 bh = common->next_buffhd_to_drain) {
1458 /* Try to submit another request if we need one */
1459 bh2 = common->next_buffhd_to_fill;
1460 if (bh2->state == BUF_STATE_EMPTY &&
1461 common->usb_amount_left > 0) {
1462 amount = min(common->usb_amount_left, FSG_BUFLEN);
1465 * Except at the end of the transfer, amount will be
1466 * equal to the buffer size, which is divisible by
1467 * the bulk-out maxpacket size.
1469 set_bulk_out_req_length(common, bh2, amount);
1470 if (!start_out_transfer(common, bh2))
1471 /* Dunno what to do if common->fsg is NULL */
1473 common->next_buffhd_to_fill = bh2->next;
1474 common->usb_amount_left -= amount;
1478 /* Wait for the data to be received */
1479 rc = sleep_thread(common, false, bh);
1483 /* Throw away the data in a filled buffer */
1484 bh->state = BUF_STATE_EMPTY;
1485 common->next_buffhd_to_drain = bh->next;
1487 /* A short packet or an error ends everything */
1488 if (bh->outreq->actual < bh->bulk_out_intended_length ||
1489 bh->outreq->status != 0) {
1490 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1497 static int finish_reply(struct fsg_common *common)
1499 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1502 switch (common->data_dir) {
1504 break; /* Nothing to send */
1507 * If we don't know whether the host wants to read or write,
1508 * this must be CB or CBI with an unknown command. We mustn't
1509 * try to send or receive any data. So stall both bulk pipes
1510 * if we can and wait for a reset.
1512 case DATA_DIR_UNKNOWN:
1513 if (!common->can_stall) {
1515 } else if (fsg_is_set(common)) {
1516 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1517 rc = halt_bulk_in_endpoint(common->fsg);
1519 /* Don't know what to do if common->fsg is NULL */
1524 /* All but the last buffer of data must have already been sent */
1525 case DATA_DIR_TO_HOST:
1526 if (common->data_size == 0) {
1527 /* Nothing to send */
1529 /* Don't know what to do if common->fsg is NULL */
1530 } else if (!fsg_is_set(common)) {
1533 /* If there's no residue, simply send the last buffer */
1534 } else if (common->residue == 0) {
1535 bh->inreq->zero = 0;
1536 if (!start_in_transfer(common, bh))
1538 common->next_buffhd_to_fill = bh->next;
1541 * For Bulk-only, mark the end of the data with a short
1542 * packet. If we are allowed to stall, halt the bulk-in
1543 * endpoint. (Note: This violates the Bulk-Only Transport
1544 * specification, which requires us to pad the data if we
1545 * don't halt the endpoint. Presumably nobody will mind.)
1548 bh->inreq->zero = 1;
1549 if (!start_in_transfer(common, bh))
1551 common->next_buffhd_to_fill = bh->next;
1552 if (common->can_stall)
1553 rc = halt_bulk_in_endpoint(common->fsg);
1558 * We have processed all we want from the data the host has sent.
1559 * There may still be outstanding bulk-out requests.
1561 case DATA_DIR_FROM_HOST:
1562 if (common->residue == 0) {
1563 /* Nothing to receive */
1565 /* Did the host stop sending unexpectedly early? */
1566 } else if (common->short_packet_received) {
1567 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1571 * We haven't processed all the incoming data. Even though
1572 * we may be allowed to stall, doing so would cause a race.
1573 * The controller may already have ACK'ed all the remaining
1574 * bulk-out packets, in which case the host wouldn't see a
1575 * STALL. Not realizing the endpoint was halted, it wouldn't
1576 * clear the halt -- leading to problems later on.
1579 } else if (common->can_stall) {
1580 if (fsg_is_set(common))
1581 fsg_set_halt(common->fsg,
1582 common->fsg->bulk_out);
1583 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1588 * We can't stall. Read in the excess data and throw it
1592 rc = throw_away_data(common);
1599 static void send_status(struct fsg_common *common)
1601 struct fsg_lun *curlun = common->curlun;
1602 struct fsg_buffhd *bh;
1603 struct bulk_cs_wrap *csw;
1605 u8 status = US_BULK_STAT_OK;
1608 /* Wait for the next buffer to become available */
1609 bh = common->next_buffhd_to_fill;
1610 rc = sleep_thread(common, false, bh);
1615 sd = curlun->sense_data;
1616 sdinfo = curlun->sense_data_info;
1617 } else if (common->bad_lun_okay)
1620 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1622 if (common->phase_error) {
1623 DBG(common, "sending phase-error status\n");
1624 status = US_BULK_STAT_PHASE;
1625 sd = SS_INVALID_COMMAND;
1626 } else if (sd != SS_NO_SENSE) {
1627 DBG(common, "sending command-failure status\n");
1628 status = US_BULK_STAT_FAIL;
1629 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1631 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1634 /* Store and send the Bulk-only CSW */
1635 csw = (void *)bh->buf;
1637 csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
1638 csw->Tag = common->tag;
1639 csw->Residue = cpu_to_le32(common->residue);
1640 csw->Status = status;
1642 bh->inreq->length = US_BULK_CS_WRAP_LEN;
1643 bh->inreq->zero = 0;
1644 if (!start_in_transfer(common, bh))
1645 /* Don't know what to do if common->fsg is NULL */
1648 common->next_buffhd_to_fill = bh->next;
1653 /*-------------------------------------------------------------------------*/
1656 * Check whether the command is properly formed and whether its data size
1657 * and direction agree with the values we already have.
1659 static int check_command(struct fsg_common *common, int cmnd_size,
1660 enum data_direction data_dir, unsigned int mask,
1661 int needs_medium, const char *name)
1664 unsigned int lun = common->cmnd[1] >> 5;
1665 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1667 struct fsg_lun *curlun;
1670 if (common->data_dir != DATA_DIR_UNKNOWN)
1671 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1673 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1674 name, cmnd_size, dirletter[(int) data_dir],
1675 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1678 * We can't reply at all until we know the correct data direction
1681 if (common->data_size_from_cmnd == 0)
1682 data_dir = DATA_DIR_NONE;
1683 if (common->data_size < common->data_size_from_cmnd) {
1685 * Host data size < Device data size is a phase error.
1686 * Carry out the command, but only transfer as much as
1689 common->data_size_from_cmnd = common->data_size;
1690 common->phase_error = 1;
1692 common->residue = common->data_size;
1693 common->usb_amount_left = common->data_size;
1695 /* Conflicting data directions is a phase error */
1696 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1697 common->phase_error = 1;
1701 /* Verify the length of the command itself */
1702 if (cmnd_size != common->cmnd_size) {
1705 * Special case workaround: There are plenty of buggy SCSI
1706 * implementations. Many have issues with cbw->Length
1707 * field passing a wrong command size. For those cases we
1708 * always try to work around the problem by using the length
1709 * sent by the host side provided it is at least as large
1710 * as the correct command length.
1711 * Examples of such cases would be MS-Windows, which issues
1712 * REQUEST SENSE with cbw->Length == 12 where it should
1713 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1714 * REQUEST SENSE with cbw->Length == 10 where it should
1717 if (cmnd_size <= common->cmnd_size) {
1718 DBG(common, "%s is buggy! Expected length %d "
1719 "but we got %d\n", name,
1720 cmnd_size, common->cmnd_size);
1721 cmnd_size = common->cmnd_size;
1723 common->phase_error = 1;
1728 /* Check that the LUN values are consistent */
1729 if (common->lun != lun)
1730 DBG(common, "using LUN %u from CBW, not LUN %u from CDB\n",
1734 curlun = common->curlun;
1736 if (common->cmnd[0] != REQUEST_SENSE) {
1737 curlun->sense_data = SS_NO_SENSE;
1738 curlun->sense_data_info = 0;
1739 curlun->info_valid = 0;
1742 common->bad_lun_okay = 0;
1745 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1746 * to use unsupported LUNs; all others may not.
1748 if (common->cmnd[0] != INQUIRY &&
1749 common->cmnd[0] != REQUEST_SENSE) {
1750 DBG(common, "unsupported LUN %u\n", common->lun);
1756 * If a unit attention condition exists, only INQUIRY and
1757 * REQUEST SENSE commands are allowed; anything else must fail.
1759 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1760 common->cmnd[0] != INQUIRY &&
1761 common->cmnd[0] != REQUEST_SENSE) {
1762 curlun->sense_data = curlun->unit_attention_data;
1763 curlun->unit_attention_data = SS_NO_SENSE;
1767 /* Check that only command bytes listed in the mask are non-zero */
1768 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1769 for (i = 1; i < cmnd_size; ++i) {
1770 if (common->cmnd[i] && !(mask & (1 << i))) {
1772 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1777 /* If the medium isn't mounted and the command needs to access
1778 * it, return an error. */
1779 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1780 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1787 /* wrapper of check_command for data size in blocks handling */
1788 static int check_command_size_in_blocks(struct fsg_common *common,
1789 int cmnd_size, enum data_direction data_dir,
1790 unsigned int mask, int needs_medium, const char *name)
1793 common->data_size_from_cmnd <<= common->curlun->blkbits;
1794 return check_command(common, cmnd_size, data_dir,
1795 mask, needs_medium, name);
1798 static int do_scsi_command(struct fsg_common *common)
1800 struct fsg_buffhd *bh;
1802 int reply = -EINVAL;
1804 static char unknown[16];
1808 /* Wait for the next buffer to become available for data or status */
1809 bh = common->next_buffhd_to_fill;
1810 common->next_buffhd_to_drain = bh;
1811 rc = sleep_thread(common, false, bh);
1815 common->phase_error = 0;
1816 common->short_packet_received = 0;
1818 down_read(&common->filesem); /* We're using the backing file */
1819 switch (common->cmnd[0]) {
1822 common->data_size_from_cmnd = common->cmnd[4];
1823 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1827 reply = do_inquiry(common, bh);
1831 common->data_size_from_cmnd = common->cmnd[4];
1832 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1836 reply = do_mode_select(common, bh);
1839 case MODE_SELECT_10:
1840 common->data_size_from_cmnd =
1841 get_unaligned_be16(&common->cmnd[7]);
1842 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1846 reply = do_mode_select(common, bh);
1850 common->data_size_from_cmnd = common->cmnd[4];
1851 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1852 (1<<1) | (1<<2) | (1<<4), 0,
1855 reply = do_mode_sense(common, bh);
1859 common->data_size_from_cmnd =
1860 get_unaligned_be16(&common->cmnd[7]);
1861 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1862 (1<<1) | (1<<2) | (3<<7), 0,
1865 reply = do_mode_sense(common, bh);
1868 case ALLOW_MEDIUM_REMOVAL:
1869 common->data_size_from_cmnd = 0;
1870 reply = check_command(common, 6, DATA_DIR_NONE,
1872 "PREVENT-ALLOW MEDIUM REMOVAL");
1874 reply = do_prevent_allow(common);
1878 i = common->cmnd[4];
1879 common->data_size_from_cmnd = (i == 0) ? 256 : i;
1880 reply = check_command_size_in_blocks(common, 6,
1885 reply = do_read(common);
1889 common->data_size_from_cmnd =
1890 get_unaligned_be16(&common->cmnd[7]);
1891 reply = check_command_size_in_blocks(common, 10,
1893 (1<<1) | (0xf<<2) | (3<<7), 1,
1896 reply = do_read(common);
1900 common->data_size_from_cmnd =
1901 get_unaligned_be32(&common->cmnd[6]);
1902 reply = check_command_size_in_blocks(common, 12,
1904 (1<<1) | (0xf<<2) | (0xf<<6), 1,
1907 reply = do_read(common);
1911 common->data_size_from_cmnd =
1912 get_unaligned_be32(&common->cmnd[10]);
1913 reply = check_command_size_in_blocks(common, 16,
1915 (1<<1) | (0xff<<2) | (0xf<<10), 1,
1918 reply = do_read(common);
1922 common->data_size_from_cmnd = 8;
1923 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1924 (0xf<<2) | (1<<8), 1,
1927 reply = do_read_capacity(common, bh);
1931 if (!common->curlun || !common->curlun->cdrom)
1933 common->data_size_from_cmnd =
1934 get_unaligned_be16(&common->cmnd[7]);
1935 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1936 (3<<7) | (0x1f<<1), 1,
1939 reply = do_read_header(common, bh);
1943 if (!common->curlun || !common->curlun->cdrom)
1945 common->data_size_from_cmnd =
1946 get_unaligned_be16(&common->cmnd[7]);
1947 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1951 reply = do_read_toc(common, bh);
1954 case READ_FORMAT_CAPACITIES:
1955 common->data_size_from_cmnd =
1956 get_unaligned_be16(&common->cmnd[7]);
1957 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1959 "READ FORMAT CAPACITIES");
1961 reply = do_read_format_capacities(common, bh);
1965 common->data_size_from_cmnd = common->cmnd[4];
1966 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1970 reply = do_request_sense(common, bh);
1973 case SERVICE_ACTION_IN_16:
1974 switch (common->cmnd[1] & 0x1f) {
1976 case SAI_READ_CAPACITY_16:
1977 common->data_size_from_cmnd =
1978 get_unaligned_be32(&common->cmnd[10]);
1979 reply = check_command(common, 16, DATA_DIR_TO_HOST,
1980 (1<<1) | (0xff<<2) | (0xf<<10) |
1982 "READ CAPACITY(16)");
1984 reply = do_read_capacity_16(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 common->data_size_from_cmnd =
2065 get_unaligned_be32(&common->cmnd[10]);
2066 reply = check_command_size_in_blocks(common, 16,
2068 (1<<1) | (0xff<<2) | (0xf<<10), 1,
2071 reply = do_write(common);
2075 * Some mandatory commands that we recognize but don't implement.
2076 * They don't mean much in this setting. It's left as an exercise
2077 * for anyone interested to implement RESERVE and RELEASE in terms
2083 case SEND_DIAGNOSTIC:
2087 common->data_size_from_cmnd = 0;
2088 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2089 reply = check_command(common, common->cmnd_size,
2090 DATA_DIR_UNKNOWN, ~0, 0, unknown);
2092 common->curlun->sense_data = SS_INVALID_COMMAND;
2097 up_read(&common->filesem);
2099 if (reply == -EINTR || signal_pending(current))
2102 /* Set up the single reply buffer for finish_reply() */
2103 if (reply == -EINVAL)
2104 reply = 0; /* Error reply length */
2105 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2106 reply = min((u32)reply, common->data_size_from_cmnd);
2107 bh->inreq->length = reply;
2108 bh->state = BUF_STATE_FULL;
2109 common->residue -= reply;
2110 } /* Otherwise it's already set */
2116 /*-------------------------------------------------------------------------*/
2118 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2120 struct usb_request *req = bh->outreq;
2121 struct bulk_cb_wrap *cbw = req->buf;
2122 struct fsg_common *common = fsg->common;
2124 /* Was this a real packet? Should it be ignored? */
2125 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2128 /* Is the CBW valid? */
2129 if (req->actual != US_BULK_CB_WRAP_LEN ||
2130 cbw->Signature != cpu_to_le32(
2132 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2134 le32_to_cpu(cbw->Signature));
2137 * The Bulk-only spec says we MUST stall the IN endpoint
2138 * (6.6.1), so it's unavoidable. It also says we must
2139 * retain this state until the next reset, but there's
2140 * no way to tell the controller driver it should ignore
2141 * Clear-Feature(HALT) requests.
2143 * We aren't required to halt the OUT endpoint; instead
2144 * we can simply accept and discard any data received
2145 * until the next reset.
2147 wedge_bulk_in_endpoint(fsg);
2148 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2152 /* Is the CBW meaningful? */
2153 if (cbw->Lun >= ARRAY_SIZE(common->luns) ||
2154 cbw->Flags & ~US_BULK_FLAG_IN || cbw->Length <= 0 ||
2155 cbw->Length > MAX_COMMAND_SIZE) {
2156 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2158 cbw->Lun, cbw->Flags, cbw->Length);
2161 * We can do anything we want here, so let's stall the
2162 * bulk pipes if we are allowed to.
2164 if (common->can_stall) {
2165 fsg_set_halt(fsg, fsg->bulk_out);
2166 halt_bulk_in_endpoint(fsg);
2171 /* Save the command for later */
2172 common->cmnd_size = cbw->Length;
2173 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2174 if (cbw->Flags & US_BULK_FLAG_IN)
2175 common->data_dir = DATA_DIR_TO_HOST;
2177 common->data_dir = DATA_DIR_FROM_HOST;
2178 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2179 if (common->data_size == 0)
2180 common->data_dir = DATA_DIR_NONE;
2181 common->lun = cbw->Lun;
2182 if (common->lun < ARRAY_SIZE(common->luns))
2183 common->curlun = common->luns[common->lun];
2185 common->curlun = NULL;
2186 common->tag = cbw->Tag;
2190 static int get_next_command(struct fsg_common *common)
2192 struct fsg_buffhd *bh;
2195 /* Wait for the next buffer to become available */
2196 bh = common->next_buffhd_to_fill;
2197 rc = sleep_thread(common, true, bh);
2201 /* Queue a request to read a Bulk-only CBW */
2202 set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
2203 if (!start_out_transfer(common, bh))
2204 /* Don't know what to do if common->fsg is NULL */
2208 * We will drain the buffer in software, which means we
2209 * can reuse it for the next filling. No need to advance
2210 * next_buffhd_to_fill.
2213 /* Wait for the CBW to arrive */
2214 rc = sleep_thread(common, true, bh);
2218 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2219 bh->state = BUF_STATE_EMPTY;
2225 /*-------------------------------------------------------------------------*/
2227 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2228 struct usb_request **preq)
2230 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2233 ERROR(common, "can't allocate request for %s\n", ep->name);
2237 /* Reset interface setting and re-init endpoint state (toggle etc). */
2238 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2240 struct fsg_dev *fsg;
2243 if (common->running)
2244 DBG(common, "reset interface\n");
2247 /* Deallocate the requests */
2251 for (i = 0; i < common->fsg_num_buffers; ++i) {
2252 struct fsg_buffhd *bh = &common->buffhds[i];
2255 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2259 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2264 /* Disable the endpoints */
2265 if (fsg->bulk_in_enabled) {
2266 usb_ep_disable(fsg->bulk_in);
2267 fsg->bulk_in_enabled = 0;
2269 if (fsg->bulk_out_enabled) {
2270 usb_ep_disable(fsg->bulk_out);
2271 fsg->bulk_out_enabled = 0;
2275 wake_up(&common->fsg_wait);
2278 common->running = 0;
2282 common->fsg = new_fsg;
2285 /* Enable the endpoints */
2286 rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
2289 rc = usb_ep_enable(fsg->bulk_in);
2292 fsg->bulk_in->driver_data = common;
2293 fsg->bulk_in_enabled = 1;
2295 rc = config_ep_by_speed(common->gadget, &(fsg->function),
2299 rc = usb_ep_enable(fsg->bulk_out);
2302 fsg->bulk_out->driver_data = common;
2303 fsg->bulk_out_enabled = 1;
2304 common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc);
2305 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2307 /* Allocate the requests */
2308 for (i = 0; i < common->fsg_num_buffers; ++i) {
2309 struct fsg_buffhd *bh = &common->buffhds[i];
2311 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2314 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2317 bh->inreq->buf = bh->outreq->buf = bh->buf;
2318 bh->inreq->context = bh->outreq->context = bh;
2319 bh->inreq->complete = bulk_in_complete;
2320 bh->outreq->complete = bulk_out_complete;
2323 common->running = 1;
2324 for (i = 0; i < ARRAY_SIZE(common->luns); ++i)
2325 if (common->luns[i])
2326 common->luns[i]->unit_attention_data =
2332 /****************************** ALT CONFIGS ******************************/
2334 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2336 struct fsg_dev *fsg = fsg_from_func(f);
2338 __raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE, fsg);
2339 return USB_GADGET_DELAYED_STATUS;
2342 static void fsg_disable(struct usb_function *f)
2344 struct fsg_dev *fsg = fsg_from_func(f);
2346 /* Disable the endpoints */
2347 if (fsg->bulk_in_enabled) {
2348 usb_ep_disable(fsg->bulk_in);
2349 fsg->bulk_in_enabled = 0;
2351 if (fsg->bulk_out_enabled) {
2352 usb_ep_disable(fsg->bulk_out);
2353 fsg->bulk_out_enabled = 0;
2356 __raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE, NULL);
2360 /*-------------------------------------------------------------------------*/
2362 static void handle_exception(struct fsg_common *common)
2365 struct fsg_buffhd *bh;
2366 enum fsg_state old_state;
2367 struct fsg_lun *curlun;
2368 unsigned int exception_req_tag;
2369 struct fsg_dev *new_fsg;
2372 * Clear the existing signals. Anything but SIGUSR1 is converted
2373 * into a high-priority EXIT exception.
2376 int sig = kernel_dequeue_signal();
2379 if (sig != SIGUSR1) {
2380 spin_lock_irq(&common->lock);
2381 if (common->state < FSG_STATE_EXIT)
2382 DBG(common, "Main thread exiting on signal\n");
2383 common->state = FSG_STATE_EXIT;
2384 spin_unlock_irq(&common->lock);
2388 /* Cancel all the pending transfers */
2389 if (likely(common->fsg)) {
2390 for (i = 0; i < common->fsg_num_buffers; ++i) {
2391 bh = &common->buffhds[i];
2392 if (bh->state == BUF_STATE_SENDING)
2393 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2394 if (bh->state == BUF_STATE_RECEIVING)
2395 usb_ep_dequeue(common->fsg->bulk_out,
2398 /* Wait for a transfer to become idle */
2399 if (sleep_thread(common, false, bh))
2403 /* Clear out the controller's fifos */
2404 if (common->fsg->bulk_in_enabled)
2405 usb_ep_fifo_flush(common->fsg->bulk_in);
2406 if (common->fsg->bulk_out_enabled)
2407 usb_ep_fifo_flush(common->fsg->bulk_out);
2411 * Reset the I/O buffer states and pointers, the SCSI
2412 * state, and the exception. Then invoke the handler.
2414 spin_lock_irq(&common->lock);
2416 for (i = 0; i < common->fsg_num_buffers; ++i) {
2417 bh = &common->buffhds[i];
2418 bh->state = BUF_STATE_EMPTY;
2420 common->next_buffhd_to_fill = &common->buffhds[0];
2421 common->next_buffhd_to_drain = &common->buffhds[0];
2422 exception_req_tag = common->exception_req_tag;
2423 new_fsg = common->exception_arg;
2424 old_state = common->state;
2425 common->state = FSG_STATE_NORMAL;
2427 if (old_state != FSG_STATE_ABORT_BULK_OUT) {
2428 for (i = 0; i < ARRAY_SIZE(common->luns); ++i) {
2429 curlun = common->luns[i];
2432 curlun->prevent_medium_removal = 0;
2433 curlun->sense_data = SS_NO_SENSE;
2434 curlun->unit_attention_data = SS_NO_SENSE;
2435 curlun->sense_data_info = 0;
2436 curlun->info_valid = 0;
2439 spin_unlock_irq(&common->lock);
2441 /* Carry out any extra actions required for the exception */
2442 switch (old_state) {
2443 case FSG_STATE_NORMAL:
2446 case FSG_STATE_ABORT_BULK_OUT:
2447 send_status(common);
2450 case FSG_STATE_PROTOCOL_RESET:
2452 * In case we were forced against our will to halt a
2453 * bulk endpoint, clear the halt now. (The SuperH UDC
2456 if (!fsg_is_set(common))
2458 if (test_and_clear_bit(IGNORE_BULK_OUT,
2459 &common->fsg->atomic_bitflags))
2460 usb_ep_clear_halt(common->fsg->bulk_in);
2462 if (common->ep0_req_tag == exception_req_tag)
2463 ep0_queue(common); /* Complete the status stage */
2466 * Technically this should go here, but it would only be
2467 * a waste of time. Ditto for the INTERFACE_CHANGE and
2468 * CONFIG_CHANGE cases.
2470 /* for (i = 0; i < common->ARRAY_SIZE(common->luns); ++i) */
2471 /* if (common->luns[i]) */
2472 /* common->luns[i]->unit_attention_data = */
2473 /* SS_RESET_OCCURRED; */
2476 case FSG_STATE_CONFIG_CHANGE:
2477 do_set_interface(common, new_fsg);
2479 usb_composite_setup_continue(common->cdev);
2482 case FSG_STATE_EXIT:
2483 do_set_interface(common, NULL); /* Free resources */
2484 spin_lock_irq(&common->lock);
2485 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2486 spin_unlock_irq(&common->lock);
2489 case FSG_STATE_TERMINATED:
2495 /*-------------------------------------------------------------------------*/
2497 static int fsg_main_thread(void *common_)
2499 struct fsg_common *common = common_;
2503 * Allow the thread to be killed by a signal, but set the signal mask
2504 * to block everything but INT, TERM, KILL, and USR1.
2506 allow_signal(SIGINT);
2507 allow_signal(SIGTERM);
2508 allow_signal(SIGKILL);
2509 allow_signal(SIGUSR1);
2511 /* Allow the thread to be frozen */
2515 while (common->state != FSG_STATE_TERMINATED) {
2516 if (exception_in_progress(common) || signal_pending(current)) {
2517 handle_exception(common);
2521 if (!common->running) {
2522 sleep_thread(common, true, NULL);
2526 if (get_next_command(common) || exception_in_progress(common))
2528 if (do_scsi_command(common) || exception_in_progress(common))
2530 if (finish_reply(common) || exception_in_progress(common))
2532 send_status(common);
2535 spin_lock_irq(&common->lock);
2536 common->thread_task = NULL;
2537 spin_unlock_irq(&common->lock);
2539 /* Eject media from all LUNs */
2541 down_write(&common->filesem);
2542 for (i = 0; i < ARRAY_SIZE(common->luns); i++) {
2543 struct fsg_lun *curlun = common->luns[i];
2545 if (curlun && fsg_lun_is_open(curlun))
2546 fsg_lun_close(curlun);
2548 up_write(&common->filesem);
2550 /* Let fsg_unbind() know the thread has exited */
2551 kthread_complete_and_exit(&common->thread_notifier, 0);
2555 /*************************** DEVICE ATTRIBUTES ***************************/
2557 static ssize_t ro_show(struct device *dev, struct device_attribute *attr, char *buf)
2559 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2561 return fsg_show_ro(curlun, buf);
2564 static ssize_t nofua_show(struct device *dev, struct device_attribute *attr,
2567 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2569 return fsg_show_nofua(curlun, buf);
2572 static ssize_t file_show(struct device *dev, struct device_attribute *attr,
2575 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2576 struct rw_semaphore *filesem = dev_get_drvdata(dev);
2578 return fsg_show_file(curlun, filesem, buf);
2581 static ssize_t ro_store(struct device *dev, struct device_attribute *attr,
2582 const char *buf, size_t count)
2584 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2585 struct rw_semaphore *filesem = dev_get_drvdata(dev);
2587 return fsg_store_ro(curlun, filesem, buf, count);
2590 static ssize_t nofua_store(struct device *dev, struct device_attribute *attr,
2591 const char *buf, size_t count)
2593 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2595 return fsg_store_nofua(curlun, buf, count);
2598 static ssize_t file_store(struct device *dev, struct device_attribute *attr,
2599 const char *buf, size_t count)
2601 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2602 struct rw_semaphore *filesem = dev_get_drvdata(dev);
2604 return fsg_store_file(curlun, filesem, buf, count);
2607 static DEVICE_ATTR_RW(nofua);
2608 /* mode wil be set in fsg_lun_attr_is_visible() */
2609 static DEVICE_ATTR(ro, 0, ro_show, ro_store);
2610 static DEVICE_ATTR(file, 0, file_show, file_store);
2612 /****************************** FSG COMMON ******************************/
2614 static void fsg_lun_release(struct device *dev)
2616 /* Nothing needs to be done */
2619 static struct fsg_common *fsg_common_setup(struct fsg_common *common)
2622 common = kzalloc(sizeof(*common), GFP_KERNEL);
2624 return ERR_PTR(-ENOMEM);
2625 common->free_storage_on_release = 1;
2627 common->free_storage_on_release = 0;
2629 init_rwsem(&common->filesem);
2630 spin_lock_init(&common->lock);
2631 init_completion(&common->thread_notifier);
2632 init_waitqueue_head(&common->io_wait);
2633 init_waitqueue_head(&common->fsg_wait);
2634 common->state = FSG_STATE_TERMINATED;
2635 memset(common->luns, 0, sizeof(common->luns));
2640 void fsg_common_set_sysfs(struct fsg_common *common, bool sysfs)
2642 common->sysfs = sysfs;
2644 EXPORT_SYMBOL_GPL(fsg_common_set_sysfs);
2646 static void _fsg_common_free_buffers(struct fsg_buffhd *buffhds, unsigned n)
2649 struct fsg_buffhd *bh = buffhds;
2658 int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n)
2660 struct fsg_buffhd *bh, *buffhds;
2663 buffhds = kcalloc(n, sizeof(*buffhds), GFP_KERNEL);
2667 /* Data buffers cyclic list */
2670 goto buffhds_first_it;
2675 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2676 if (unlikely(!bh->buf))
2681 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
2682 common->fsg_num_buffers = n;
2683 common->buffhds = buffhds;
2689 * "buf"s pointed to by heads after n - i are NULL
2690 * so releasing them won't hurt
2692 _fsg_common_free_buffers(buffhds, n);
2696 EXPORT_SYMBOL_GPL(fsg_common_set_num_buffers);
2698 void fsg_common_remove_lun(struct fsg_lun *lun)
2700 if (device_is_registered(&lun->dev))
2701 device_unregister(&lun->dev);
2705 EXPORT_SYMBOL_GPL(fsg_common_remove_lun);
2707 static void _fsg_common_remove_luns(struct fsg_common *common, int n)
2711 for (i = 0; i < n; ++i)
2712 if (common->luns[i]) {
2713 fsg_common_remove_lun(common->luns[i]);
2714 common->luns[i] = NULL;
2718 void fsg_common_remove_luns(struct fsg_common *common)
2720 _fsg_common_remove_luns(common, ARRAY_SIZE(common->luns));
2722 EXPORT_SYMBOL_GPL(fsg_common_remove_luns);
2724 void fsg_common_free_buffers(struct fsg_common *common)
2726 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
2727 common->buffhds = NULL;
2729 EXPORT_SYMBOL_GPL(fsg_common_free_buffers);
2731 int fsg_common_set_cdev(struct fsg_common *common,
2732 struct usb_composite_dev *cdev, bool can_stall)
2734 struct usb_string *us;
2736 common->gadget = cdev->gadget;
2737 common->ep0 = cdev->gadget->ep0;
2738 common->ep0req = cdev->req;
2739 common->cdev = cdev;
2741 us = usb_gstrings_attach(cdev, fsg_strings_array,
2742 ARRAY_SIZE(fsg_strings));
2746 fsg_intf_desc.iInterface = us[FSG_STRING_INTERFACE].id;
2749 * Some peripheral controllers are known not to be able to
2750 * halt bulk endpoints correctly. If one of them is present,
2753 common->can_stall = can_stall &&
2754 gadget_is_stall_supported(common->gadget);
2758 EXPORT_SYMBOL_GPL(fsg_common_set_cdev);
2760 static struct attribute *fsg_lun_dev_attrs[] = {
2762 &dev_attr_file.attr,
2763 &dev_attr_nofua.attr,
2767 static umode_t fsg_lun_dev_is_visible(struct kobject *kobj,
2768 struct attribute *attr, int idx)
2770 struct device *dev = kobj_to_dev(kobj);
2771 struct fsg_lun *lun = fsg_lun_from_dev(dev);
2773 if (attr == &dev_attr_ro.attr)
2774 return lun->cdrom ? S_IRUGO : (S_IWUSR | S_IRUGO);
2775 if (attr == &dev_attr_file.attr)
2776 return lun->removable ? (S_IWUSR | S_IRUGO) : S_IRUGO;
2780 static const struct attribute_group fsg_lun_dev_group = {
2781 .attrs = fsg_lun_dev_attrs,
2782 .is_visible = fsg_lun_dev_is_visible,
2785 static const struct attribute_group *fsg_lun_dev_groups[] = {
2790 int fsg_common_create_lun(struct fsg_common *common, struct fsg_lun_config *cfg,
2791 unsigned int id, const char *name,
2792 const char **name_pfx)
2794 struct fsg_lun *lun;
2798 if (id >= ARRAY_SIZE(common->luns))
2801 if (common->luns[id])
2804 if (!cfg->filename && !cfg->removable) {
2805 pr_err("no file given for LUN%d\n", id);
2809 lun = kzalloc(sizeof(*lun), GFP_KERNEL);
2813 lun->name_pfx = name_pfx;
2815 lun->cdrom = !!cfg->cdrom;
2816 lun->ro = cfg->cdrom || cfg->ro;
2817 lun->initially_ro = lun->ro;
2818 lun->removable = !!cfg->removable;
2820 if (!common->sysfs) {
2821 /* we DON'T own the name!*/
2824 lun->dev.release = fsg_lun_release;
2825 lun->dev.parent = &common->gadget->dev;
2826 lun->dev.groups = fsg_lun_dev_groups;
2827 dev_set_drvdata(&lun->dev, &common->filesem);
2828 dev_set_name(&lun->dev, "%s", name);
2829 lun->name = dev_name(&lun->dev);
2831 rc = device_register(&lun->dev);
2833 pr_info("failed to register LUN%d: %d\n", id, rc);
2834 put_device(&lun->dev);
2839 common->luns[id] = lun;
2841 if (cfg->filename) {
2842 rc = fsg_lun_open(lun, cfg->filename);
2847 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2849 if (fsg_lun_is_open(lun)) {
2852 p = file_path(lun->filp, pathbuf, PATH_MAX);
2857 pr_info("LUN: %s%s%sfile: %s\n",
2858 lun->removable ? "removable " : "",
2859 lun->ro ? "read only " : "",
2860 lun->cdrom ? "CD-ROM " : "",
2867 if (device_is_registered(&lun->dev))
2868 device_unregister(&lun->dev);
2870 common->luns[id] = NULL;
2875 EXPORT_SYMBOL_GPL(fsg_common_create_lun);
2877 int fsg_common_create_luns(struct fsg_common *common, struct fsg_config *cfg)
2879 char buf[8]; /* enough for 100000000 different numbers, decimal */
2882 fsg_common_remove_luns(common);
2884 for (i = 0; i < cfg->nluns; ++i) {
2885 snprintf(buf, sizeof(buf), "lun%d", i);
2886 rc = fsg_common_create_lun(common, &cfg->luns[i], i, buf, NULL);
2891 pr_info("Number of LUNs=%d\n", cfg->nluns);
2896 _fsg_common_remove_luns(common, i);
2899 EXPORT_SYMBOL_GPL(fsg_common_create_luns);
2901 void fsg_common_set_inquiry_string(struct fsg_common *common, const char *vn,
2906 /* Prepare inquiryString */
2907 i = get_default_bcdDevice();
2908 snprintf(common->inquiry_string, sizeof(common->inquiry_string),
2909 "%-8s%-16s%04x", vn ?: "Linux",
2910 /* Assume product name dependent on the first LUN */
2911 pn ?: ((*common->luns)->cdrom
2913 : "File-Stor Gadget"),
2916 EXPORT_SYMBOL_GPL(fsg_common_set_inquiry_string);
2918 static void fsg_common_release(struct fsg_common *common)
2922 /* If the thread isn't already dead, tell it to exit now */
2923 if (common->state != FSG_STATE_TERMINATED) {
2924 raise_exception(common, FSG_STATE_EXIT);
2925 wait_for_completion(&common->thread_notifier);
2928 for (i = 0; i < ARRAY_SIZE(common->luns); ++i) {
2929 struct fsg_lun *lun = common->luns[i];
2933 if (device_is_registered(&lun->dev))
2934 device_unregister(&lun->dev);
2938 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
2939 if (common->free_storage_on_release)
2944 /*-------------------------------------------------------------------------*/
2946 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
2948 struct fsg_dev *fsg = fsg_from_func(f);
2949 struct fsg_common *common = fsg->common;
2950 struct usb_gadget *gadget = c->cdev->gadget;
2955 struct fsg_opts *opts;
2957 /* Don't allow to bind if we don't have at least one LUN */
2958 ret = _fsg_common_get_max_lun(common);
2960 pr_err("There should be at least one LUN.\n");
2964 opts = fsg_opts_from_func_inst(f->fi);
2965 if (!opts->no_configfs) {
2966 ret = fsg_common_set_cdev(fsg->common, c->cdev,
2967 fsg->common->can_stall);
2970 fsg_common_set_inquiry_string(fsg->common, NULL, NULL);
2973 if (!common->thread_task) {
2974 common->state = FSG_STATE_NORMAL;
2975 common->thread_task =
2976 kthread_create(fsg_main_thread, common, "file-storage");
2977 if (IS_ERR(common->thread_task)) {
2978 ret = PTR_ERR(common->thread_task);
2979 common->thread_task = NULL;
2980 common->state = FSG_STATE_TERMINATED;
2983 DBG(common, "I/O thread pid: %d\n",
2984 task_pid_nr(common->thread_task));
2985 wake_up_process(common->thread_task);
2988 fsg->gadget = gadget;
2991 i = usb_interface_id(c, f);
2994 fsg_intf_desc.bInterfaceNumber = i;
2995 fsg->interface_number = i;
2997 /* Find all the endpoints we will use */
2998 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
3003 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
3008 /* Assume endpoint addresses are the same for both speeds */
3009 fsg_hs_bulk_in_desc.bEndpointAddress =
3010 fsg_fs_bulk_in_desc.bEndpointAddress;
3011 fsg_hs_bulk_out_desc.bEndpointAddress =
3012 fsg_fs_bulk_out_desc.bEndpointAddress;
3014 /* Calculate bMaxBurst, we know packet size is 1024 */
3015 max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15);
3017 fsg_ss_bulk_in_desc.bEndpointAddress =
3018 fsg_fs_bulk_in_desc.bEndpointAddress;
3019 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
3021 fsg_ss_bulk_out_desc.bEndpointAddress =
3022 fsg_fs_bulk_out_desc.bEndpointAddress;
3023 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
3025 ret = usb_assign_descriptors(f, fsg_fs_function, fsg_hs_function,
3026 fsg_ss_function, fsg_ss_function);
3033 ERROR(fsg, "unable to autoconfigure all endpoints\n");
3036 /* terminate the thread */
3037 if (fsg->common->state != FSG_STATE_TERMINATED) {
3038 raise_exception(fsg->common, FSG_STATE_EXIT);
3039 wait_for_completion(&fsg->common->thread_notifier);
3044 /****************************** ALLOCATE FUNCTION *************************/
3046 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
3048 struct fsg_dev *fsg = fsg_from_func(f);
3049 struct fsg_common *common = fsg->common;
3051 DBG(fsg, "unbind\n");
3052 if (fsg->common->fsg == fsg) {
3053 __raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE, NULL);
3054 /* FIXME: make interruptible or killable somehow? */
3055 wait_event(common->fsg_wait, common->fsg != fsg);
3058 usb_free_all_descriptors(&fsg->function);
3061 static inline struct fsg_lun_opts *to_fsg_lun_opts(struct config_item *item)
3063 return container_of(to_config_group(item), struct fsg_lun_opts, group);
3066 static inline struct fsg_opts *to_fsg_opts(struct config_item *item)
3068 return container_of(to_config_group(item), struct fsg_opts,
3072 static void fsg_lun_attr_release(struct config_item *item)
3074 struct fsg_lun_opts *lun_opts;
3076 lun_opts = to_fsg_lun_opts(item);
3080 static struct configfs_item_operations fsg_lun_item_ops = {
3081 .release = fsg_lun_attr_release,
3084 static ssize_t fsg_lun_opts_file_show(struct config_item *item, char *page)
3086 struct fsg_lun_opts *opts = to_fsg_lun_opts(item);
3087 struct fsg_opts *fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3089 return fsg_show_file(opts->lun, &fsg_opts->common->filesem, page);
3092 static ssize_t fsg_lun_opts_file_store(struct config_item *item,
3093 const char *page, size_t len)
3095 struct fsg_lun_opts *opts = to_fsg_lun_opts(item);
3096 struct fsg_opts *fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3098 return fsg_store_file(opts->lun, &fsg_opts->common->filesem, page, len);
3101 CONFIGFS_ATTR(fsg_lun_opts_, file);
3103 static ssize_t fsg_lun_opts_ro_show(struct config_item *item, char *page)
3105 return fsg_show_ro(to_fsg_lun_opts(item)->lun, page);
3108 static ssize_t fsg_lun_opts_ro_store(struct config_item *item,
3109 const char *page, size_t len)
3111 struct fsg_lun_opts *opts = to_fsg_lun_opts(item);
3112 struct fsg_opts *fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3114 return fsg_store_ro(opts->lun, &fsg_opts->common->filesem, page, len);
3117 CONFIGFS_ATTR(fsg_lun_opts_, ro);
3119 static ssize_t fsg_lun_opts_removable_show(struct config_item *item,
3122 return fsg_show_removable(to_fsg_lun_opts(item)->lun, page);
3125 static ssize_t fsg_lun_opts_removable_store(struct config_item *item,
3126 const char *page, size_t len)
3128 return fsg_store_removable(to_fsg_lun_opts(item)->lun, page, len);
3131 CONFIGFS_ATTR(fsg_lun_opts_, removable);
3133 static ssize_t fsg_lun_opts_cdrom_show(struct config_item *item, char *page)
3135 return fsg_show_cdrom(to_fsg_lun_opts(item)->lun, page);
3138 static ssize_t fsg_lun_opts_cdrom_store(struct config_item *item,
3139 const char *page, size_t len)
3141 struct fsg_lun_opts *opts = to_fsg_lun_opts(item);
3142 struct fsg_opts *fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3144 return fsg_store_cdrom(opts->lun, &fsg_opts->common->filesem, page,
3148 CONFIGFS_ATTR(fsg_lun_opts_, cdrom);
3150 static ssize_t fsg_lun_opts_nofua_show(struct config_item *item, char *page)
3152 return fsg_show_nofua(to_fsg_lun_opts(item)->lun, page);
3155 static ssize_t fsg_lun_opts_nofua_store(struct config_item *item,
3156 const char *page, size_t len)
3158 return fsg_store_nofua(to_fsg_lun_opts(item)->lun, page, len);
3161 CONFIGFS_ATTR(fsg_lun_opts_, nofua);
3163 static ssize_t fsg_lun_opts_inquiry_string_show(struct config_item *item,
3166 return fsg_show_inquiry_string(to_fsg_lun_opts(item)->lun, page);
3169 static ssize_t fsg_lun_opts_inquiry_string_store(struct config_item *item,
3170 const char *page, size_t len)
3172 return fsg_store_inquiry_string(to_fsg_lun_opts(item)->lun, page, len);
3175 CONFIGFS_ATTR(fsg_lun_opts_, inquiry_string);
3177 static struct configfs_attribute *fsg_lun_attrs[] = {
3178 &fsg_lun_opts_attr_file,
3179 &fsg_lun_opts_attr_ro,
3180 &fsg_lun_opts_attr_removable,
3181 &fsg_lun_opts_attr_cdrom,
3182 &fsg_lun_opts_attr_nofua,
3183 &fsg_lun_opts_attr_inquiry_string,
3187 static const struct config_item_type fsg_lun_type = {
3188 .ct_item_ops = &fsg_lun_item_ops,
3189 .ct_attrs = fsg_lun_attrs,
3190 .ct_owner = THIS_MODULE,
3193 static struct config_group *fsg_lun_make(struct config_group *group,
3196 struct fsg_lun_opts *opts;
3197 struct fsg_opts *fsg_opts;
3198 struct fsg_lun_config config;
3203 num_str = strchr(name, '.');
3205 pr_err("Unable to locate . in LUN.NUMBER\n");
3206 return ERR_PTR(-EINVAL);
3210 ret = kstrtou8(num_str, 0, &num);
3212 return ERR_PTR(ret);
3214 fsg_opts = to_fsg_opts(&group->cg_item);
3215 if (num >= FSG_MAX_LUNS)
3216 return ERR_PTR(-ERANGE);
3217 num = array_index_nospec(num, FSG_MAX_LUNS);
3219 mutex_lock(&fsg_opts->lock);
3220 if (fsg_opts->refcnt || fsg_opts->common->luns[num]) {
3225 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
3231 memset(&config, 0, sizeof(config));
3232 config.removable = true;
3234 ret = fsg_common_create_lun(fsg_opts->common, &config, num, name,
3235 (const char **)&group->cg_item.ci_name);
3240 opts->lun = fsg_opts->common->luns[num];
3242 mutex_unlock(&fsg_opts->lock);
3244 config_group_init_type_name(&opts->group, name, &fsg_lun_type);
3246 return &opts->group;
3248 mutex_unlock(&fsg_opts->lock);
3249 return ERR_PTR(ret);
3252 static void fsg_lun_drop(struct config_group *group, struct config_item *item)
3254 struct fsg_lun_opts *lun_opts;
3255 struct fsg_opts *fsg_opts;
3257 lun_opts = to_fsg_lun_opts(item);
3258 fsg_opts = to_fsg_opts(&group->cg_item);
3260 mutex_lock(&fsg_opts->lock);
3261 if (fsg_opts->refcnt) {
3262 struct config_item *gadget;
3264 gadget = group->cg_item.ci_parent->ci_parent;
3265 unregister_gadget_item(gadget);
3268 fsg_common_remove_lun(lun_opts->lun);
3269 fsg_opts->common->luns[lun_opts->lun_id] = NULL;
3270 lun_opts->lun_id = 0;
3271 mutex_unlock(&fsg_opts->lock);
3273 config_item_put(item);
3276 static void fsg_attr_release(struct config_item *item)
3278 struct fsg_opts *opts = to_fsg_opts(item);
3280 usb_put_function_instance(&opts->func_inst);
3283 static struct configfs_item_operations fsg_item_ops = {
3284 .release = fsg_attr_release,
3287 static ssize_t fsg_opts_stall_show(struct config_item *item, char *page)
3289 struct fsg_opts *opts = to_fsg_opts(item);
3292 mutex_lock(&opts->lock);
3293 result = sprintf(page, "%d", opts->common->can_stall);
3294 mutex_unlock(&opts->lock);
3299 static ssize_t fsg_opts_stall_store(struct config_item *item, const char *page,
3302 struct fsg_opts *opts = to_fsg_opts(item);
3306 mutex_lock(&opts->lock);
3309 mutex_unlock(&opts->lock);
3313 ret = strtobool(page, &stall);
3315 opts->common->can_stall = stall;
3319 mutex_unlock(&opts->lock);
3324 CONFIGFS_ATTR(fsg_opts_, stall);
3326 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
3327 static ssize_t fsg_opts_num_buffers_show(struct config_item *item, char *page)
3329 struct fsg_opts *opts = to_fsg_opts(item);
3332 mutex_lock(&opts->lock);
3333 result = sprintf(page, "%d", opts->common->fsg_num_buffers);
3334 mutex_unlock(&opts->lock);
3339 static ssize_t fsg_opts_num_buffers_store(struct config_item *item,
3340 const char *page, size_t len)
3342 struct fsg_opts *opts = to_fsg_opts(item);
3346 mutex_lock(&opts->lock);
3351 ret = kstrtou8(page, 0, &num);
3355 ret = fsg_common_set_num_buffers(opts->common, num);
3361 mutex_unlock(&opts->lock);
3365 CONFIGFS_ATTR(fsg_opts_, num_buffers);
3368 static struct configfs_attribute *fsg_attrs[] = {
3369 &fsg_opts_attr_stall,
3370 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
3371 &fsg_opts_attr_num_buffers,
3376 static struct configfs_group_operations fsg_group_ops = {
3377 .make_group = fsg_lun_make,
3378 .drop_item = fsg_lun_drop,
3381 static const struct config_item_type fsg_func_type = {
3382 .ct_item_ops = &fsg_item_ops,
3383 .ct_group_ops = &fsg_group_ops,
3384 .ct_attrs = fsg_attrs,
3385 .ct_owner = THIS_MODULE,
3388 static void fsg_free_inst(struct usb_function_instance *fi)
3390 struct fsg_opts *opts;
3392 opts = fsg_opts_from_func_inst(fi);
3393 fsg_common_release(opts->common);
3397 static struct usb_function_instance *fsg_alloc_inst(void)
3399 struct fsg_opts *opts;
3400 struct fsg_lun_config config;
3403 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
3405 return ERR_PTR(-ENOMEM);
3406 mutex_init(&opts->lock);
3407 opts->func_inst.free_func_inst = fsg_free_inst;
3408 opts->common = fsg_common_setup(opts->common);
3409 if (IS_ERR(opts->common)) {
3410 rc = PTR_ERR(opts->common);
3414 rc = fsg_common_set_num_buffers(opts->common,
3415 CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS);
3417 goto release_common;
3419 pr_info(FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
3421 memset(&config, 0, sizeof(config));
3422 config.removable = true;
3423 rc = fsg_common_create_lun(opts->common, &config, 0, "lun.0",
3424 (const char **)&opts->func_inst.group.cg_item.ci_name);
3426 goto release_buffers;
3428 opts->lun0.lun = opts->common->luns[0];
3429 opts->lun0.lun_id = 0;
3431 config_group_init_type_name(&opts->func_inst.group, "", &fsg_func_type);
3433 config_group_init_type_name(&opts->lun0.group, "lun.0", &fsg_lun_type);
3434 configfs_add_default_group(&opts->lun0.group, &opts->func_inst.group);
3436 return &opts->func_inst;
3439 fsg_common_free_buffers(opts->common);
3441 kfree(opts->common);
3447 static void fsg_free(struct usb_function *f)
3449 struct fsg_dev *fsg;
3450 struct fsg_opts *opts;
3452 fsg = container_of(f, struct fsg_dev, function);
3453 opts = container_of(f->fi, struct fsg_opts, func_inst);
3455 mutex_lock(&opts->lock);
3457 mutex_unlock(&opts->lock);
3462 static struct usb_function *fsg_alloc(struct usb_function_instance *fi)
3464 struct fsg_opts *opts = fsg_opts_from_func_inst(fi);
3465 struct fsg_common *common = opts->common;
3466 struct fsg_dev *fsg;
3468 fsg = kzalloc(sizeof(*fsg), GFP_KERNEL);
3470 return ERR_PTR(-ENOMEM);
3472 mutex_lock(&opts->lock);
3474 mutex_unlock(&opts->lock);
3476 fsg->function.name = FSG_DRIVER_DESC;
3477 fsg->function.bind = fsg_bind;
3478 fsg->function.unbind = fsg_unbind;
3479 fsg->function.setup = fsg_setup;
3480 fsg->function.set_alt = fsg_set_alt;
3481 fsg->function.disable = fsg_disable;
3482 fsg->function.free_func = fsg_free;
3484 fsg->common = common;
3486 return &fsg->function;
3489 DECLARE_USB_FUNCTION_INIT(mass_storage, fsg_alloc_inst, fsg_alloc);
3490 MODULE_LICENSE("GPL");
3491 MODULE_AUTHOR("Michal Nazarewicz");
3493 /************************* Module parameters *************************/
3496 void fsg_config_from_params(struct fsg_config *cfg,
3497 const struct fsg_module_parameters *params,
3498 unsigned int fsg_num_buffers)
3500 struct fsg_lun_config *lun;
3503 /* Configure LUNs */
3505 min(params->luns ?: (params->file_count ?: 1u),
3506 (unsigned)FSG_MAX_LUNS);
3507 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3508 lun->ro = !!params->ro[i];
3509 lun->cdrom = !!params->cdrom[i];
3510 lun->removable = !!params->removable[i];
3512 params->file_count > i && params->file[i][0]
3517 /* Let MSF use defaults */
3518 cfg->vendor_name = NULL;
3519 cfg->product_name = NULL;
3522 cfg->private_data = NULL;
3525 cfg->can_stall = params->stall;
3526 cfg->fsg_num_buffers = fsg_num_buffers;
3528 EXPORT_SYMBOL_GPL(fsg_config_from_params);