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/kstrtox.h>
180 #include <linux/kthread.h>
181 #include <linux/sched/signal.h>
182 #include <linux/limits.h>
183 #include <linux/pagemap.h>
184 #include <linux/rwsem.h>
185 #include <linux/slab.h>
186 #include <linux/spinlock.h>
187 #include <linux/string.h>
188 #include <linux/freezer.h>
189 #include <linux/module.h>
190 #include <linux/uaccess.h>
191 #include <asm/unaligned.h>
193 #include <linux/usb/ch9.h>
194 #include <linux/usb/gadget.h>
195 #include <linux/usb/composite.h>
197 #include <linux/nospec.h>
199 #include "configfs.h"
202 /*------------------------------------------------------------------------*/
204 #define FSG_DRIVER_DESC "Mass Storage Function"
205 #define FSG_DRIVER_VERSION "2009/09/11"
207 static const char fsg_string_interface[] = "Mass Storage";
209 #include "storage_common.h"
210 #include "f_mass_storage.h"
212 /* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
213 static struct usb_string fsg_strings[] = {
214 {FSG_STRING_INTERFACE, fsg_string_interface},
218 static struct usb_gadget_strings fsg_stringtab = {
219 .language = 0x0409, /* en-us */
220 .strings = fsg_strings,
223 static struct usb_gadget_strings *fsg_strings_array[] = {
228 /*-------------------------------------------------------------------------*/
233 /* Data shared by all the FSG instances. */
235 struct usb_gadget *gadget;
236 struct usb_composite_dev *cdev;
238 wait_queue_head_t io_wait;
239 wait_queue_head_t fsg_wait;
241 /* filesem protects: backing files in use */
242 struct rw_semaphore filesem;
244 /* lock protects: state and thread_task */
247 struct usb_ep *ep0; /* Copy of gadget->ep0 */
248 struct usb_request *ep0req; /* Copy of cdev->req */
249 unsigned int ep0_req_tag;
251 struct fsg_buffhd *next_buffhd_to_fill;
252 struct fsg_buffhd *next_buffhd_to_drain;
253 struct fsg_buffhd *buffhds;
254 unsigned int fsg_num_buffers;
257 u8 cmnd[MAX_COMMAND_SIZE];
260 struct fsg_lun *luns[FSG_MAX_LUNS];
261 struct fsg_lun *curlun;
263 unsigned int bulk_out_maxpacket;
264 enum fsg_state state; /* For exception handling */
265 unsigned int exception_req_tag;
268 enum data_direction data_dir;
270 u32 data_size_from_cmnd;
275 unsigned int can_stall:1;
276 unsigned int free_storage_on_release:1;
277 unsigned int phase_error:1;
278 unsigned int short_packet_received:1;
279 unsigned int bad_lun_okay:1;
280 unsigned int running:1;
281 unsigned int sysfs:1;
283 struct completion thread_notifier;
284 struct task_struct *thread_task;
286 /* Gadget's private data. */
289 char inquiry_string[INQUIRY_STRING_LEN];
293 struct usb_function function;
294 struct usb_gadget *gadget; /* Copy of cdev->gadget */
295 struct fsg_common *common;
297 u16 interface_number;
299 unsigned int bulk_in_enabled:1;
300 unsigned int bulk_out_enabled:1;
302 unsigned long atomic_bitflags;
303 #define IGNORE_BULK_OUT 0
305 struct usb_ep *bulk_in;
306 struct usb_ep *bulk_out;
309 static inline int __fsg_is_set(struct fsg_common *common,
310 const char *func, unsigned line)
314 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
319 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
321 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
323 return container_of(f, struct fsg_dev, function);
326 static int exception_in_progress(struct fsg_common *common)
328 return common->state > FSG_STATE_NORMAL;
331 /* Make bulk-out requests be divisible by the maxpacket size */
332 static void set_bulk_out_req_length(struct fsg_common *common,
333 struct fsg_buffhd *bh, unsigned int length)
337 bh->bulk_out_intended_length = length;
338 rem = length % common->bulk_out_maxpacket;
340 length += common->bulk_out_maxpacket - rem;
341 bh->outreq->length = length;
345 /*-------------------------------------------------------------------------*/
347 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
351 if (ep == fsg->bulk_in)
353 else if (ep == fsg->bulk_out)
357 DBG(fsg, "%s set halt\n", name);
358 return usb_ep_set_halt(ep);
362 /*-------------------------------------------------------------------------*/
364 /* These routines may be called in process context or in_irq */
366 static void __raise_exception(struct fsg_common *common, enum fsg_state new_state,
372 * Do nothing if a higher-priority exception is already in progress.
373 * If a lower-or-equal priority exception is in progress, preempt it
374 * and notify the main thread by sending it a signal.
376 spin_lock_irqsave(&common->lock, flags);
377 if (common->state <= new_state) {
378 common->exception_req_tag = common->ep0_req_tag;
379 common->state = new_state;
380 common->exception_arg = arg;
381 if (common->thread_task)
382 send_sig_info(SIGUSR1, SEND_SIG_PRIV,
383 common->thread_task);
385 spin_unlock_irqrestore(&common->lock, flags);
388 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
390 __raise_exception(common, new_state, NULL);
393 /*-------------------------------------------------------------------------*/
395 static int ep0_queue(struct fsg_common *common)
399 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
400 common->ep0->driver_data = common;
401 if (rc != 0 && rc != -ESHUTDOWN) {
402 /* We can't do much more than wait for a reset */
403 WARNING(common, "error in submission: %s --> %d\n",
404 common->ep0->name, rc);
410 /*-------------------------------------------------------------------------*/
412 /* Completion handlers. These always run in_irq. */
414 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
416 struct fsg_common *common = ep->driver_data;
417 struct fsg_buffhd *bh = req->context;
419 if (req->status || req->actual != req->length)
420 DBG(common, "%s --> %d, %u/%u\n", __func__,
421 req->status, req->actual, req->length);
422 if (req->status == -ECONNRESET) /* Request was cancelled */
423 usb_ep_fifo_flush(ep);
425 /* Synchronize with the smp_load_acquire() in sleep_thread() */
426 smp_store_release(&bh->state, BUF_STATE_EMPTY);
427 wake_up(&common->io_wait);
430 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
432 struct fsg_common *common = ep->driver_data;
433 struct fsg_buffhd *bh = req->context;
435 dump_msg(common, "bulk-out", req->buf, req->actual);
436 if (req->status || req->actual != bh->bulk_out_intended_length)
437 DBG(common, "%s --> %d, %u/%u\n", __func__,
438 req->status, req->actual, bh->bulk_out_intended_length);
439 if (req->status == -ECONNRESET) /* Request was cancelled */
440 usb_ep_fifo_flush(ep);
442 /* Synchronize with the smp_load_acquire() in sleep_thread() */
443 smp_store_release(&bh->state, BUF_STATE_FULL);
444 wake_up(&common->io_wait);
447 static int _fsg_common_get_max_lun(struct fsg_common *common)
449 int i = ARRAY_SIZE(common->luns) - 1;
451 while (i >= 0 && !common->luns[i])
457 static int fsg_setup(struct usb_function *f,
458 const struct usb_ctrlrequest *ctrl)
460 struct fsg_dev *fsg = fsg_from_func(f);
461 struct usb_request *req = fsg->common->ep0req;
462 u16 w_index = le16_to_cpu(ctrl->wIndex);
463 u16 w_value = le16_to_cpu(ctrl->wValue);
464 u16 w_length = le16_to_cpu(ctrl->wLength);
466 if (!fsg_is_set(fsg->common))
469 ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
472 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
474 switch (ctrl->bRequest) {
476 case US_BULK_RESET_REQUEST:
477 if (ctrl->bRequestType !=
478 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
480 if (w_index != fsg->interface_number || w_value != 0 ||
485 * Raise an exception to stop the current operation
486 * and reinitialize our state.
488 DBG(fsg, "bulk reset request\n");
489 raise_exception(fsg->common, FSG_STATE_PROTOCOL_RESET);
490 return USB_GADGET_DELAYED_STATUS;
492 case US_BULK_GET_MAX_LUN:
493 if (ctrl->bRequestType !=
494 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
496 if (w_index != fsg->interface_number || w_value != 0 ||
499 VDBG(fsg, "get max LUN\n");
500 *(u8 *)req->buf = _fsg_common_get_max_lun(fsg->common);
502 /* Respond with data/status */
503 req->length = min((u16)1, w_length);
504 return ep0_queue(fsg->common);
508 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
509 ctrl->bRequestType, ctrl->bRequest,
510 le16_to_cpu(ctrl->wValue), w_index, w_length);
515 /*-------------------------------------------------------------------------*/
517 /* All the following routines run in process context */
519 /* Use this for bulk or interrupt transfers, not ep0 */
520 static int start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
521 struct usb_request *req)
525 if (ep == fsg->bulk_in)
526 dump_msg(fsg, "bulk-in", req->buf, req->length);
528 rc = usb_ep_queue(ep, req, GFP_KERNEL);
531 /* We can't do much more than wait for a reset */
535 * Note: currently the net2280 driver fails zero-length
536 * submissions if DMA is enabled.
538 if (rc != -ESHUTDOWN &&
539 !(rc == -EOPNOTSUPP && req->length == 0))
540 WARNING(fsg, "error in submission: %s --> %d\n",
546 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
548 if (!fsg_is_set(common))
550 bh->state = BUF_STATE_SENDING;
551 if (start_transfer(common->fsg, common->fsg->bulk_in, bh->inreq))
552 bh->state = BUF_STATE_EMPTY;
556 static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
558 if (!fsg_is_set(common))
560 bh->state = BUF_STATE_RECEIVING;
561 if (start_transfer(common->fsg, common->fsg->bulk_out, bh->outreq))
562 bh->state = BUF_STATE_FULL;
566 static int sleep_thread(struct fsg_common *common, bool can_freeze,
567 struct fsg_buffhd *bh)
571 /* Wait until a signal arrives or bh is no longer busy */
574 * synchronize with the smp_store_release(&bh->state) in
575 * bulk_in_complete() or bulk_out_complete()
577 rc = wait_event_freezable(common->io_wait,
578 bh && smp_load_acquire(&bh->state) >=
581 rc = wait_event_interruptible(common->io_wait,
582 bh && smp_load_acquire(&bh->state) >=
584 return rc ? -EINTR : 0;
588 /*-------------------------------------------------------------------------*/
590 static int do_read(struct fsg_common *common)
592 struct fsg_lun *curlun = common->curlun;
594 struct fsg_buffhd *bh;
597 loff_t file_offset, file_offset_tmp;
602 * Get the starting Logical Block Address and check that it's
605 if (common->cmnd[0] == READ_6)
606 lba = get_unaligned_be24(&common->cmnd[1]);
608 if (common->cmnd[0] == READ_16)
609 lba = get_unaligned_be64(&common->cmnd[2]);
610 else /* READ_10 or READ_12 */
611 lba = get_unaligned_be32(&common->cmnd[2]);
614 * We allow DPO (Disable Page Out = don't save data in the
615 * cache) and FUA (Force Unit Access = don't read from the
616 * cache), but we don't implement them.
618 if ((common->cmnd[1] & ~0x18) != 0) {
619 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
623 if (lba >= curlun->num_sectors) {
624 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
627 file_offset = ((loff_t) lba) << curlun->blkbits;
629 /* Carry out the file reads */
630 amount_left = common->data_size_from_cmnd;
631 if (unlikely(amount_left == 0))
632 return -EIO; /* No default reply */
636 * Figure out how much we need to read:
637 * Try to read the remaining amount.
638 * But don't read more than the buffer size.
639 * And don't try to read past the end of the file.
641 amount = min(amount_left, FSG_BUFLEN);
642 amount = min((loff_t)amount,
643 curlun->file_length - file_offset);
645 /* Wait for the next buffer to become available */
646 bh = common->next_buffhd_to_fill;
647 rc = sleep_thread(common, false, bh);
652 * If we were asked to read past the end of file,
653 * end with an empty buffer.
657 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
658 curlun->sense_data_info =
659 file_offset >> curlun->blkbits;
660 curlun->info_valid = 1;
661 bh->inreq->length = 0;
662 bh->state = BUF_STATE_FULL;
666 /* Perform the read */
667 file_offset_tmp = file_offset;
668 nread = kernel_read(curlun->filp, bh->buf, amount,
670 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
671 (unsigned long long)file_offset, (int)nread);
672 if (signal_pending(current))
676 LDBG(curlun, "error in file read: %d\n", (int)nread);
678 } else if (nread < amount) {
679 LDBG(curlun, "partial file read: %d/%u\n",
681 nread = round_down(nread, curlun->blksize);
683 file_offset += nread;
684 amount_left -= nread;
685 common->residue -= nread;
688 * Except at the end of the transfer, nread will be
689 * equal to the buffer size, which is divisible by the
690 * bulk-in maxpacket size.
692 bh->inreq->length = nread;
693 bh->state = BUF_STATE_FULL;
695 /* If an error occurred, report it and its position */
696 if (nread < amount) {
697 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
698 curlun->sense_data_info =
699 file_offset >> curlun->blkbits;
700 curlun->info_valid = 1;
704 if (amount_left == 0)
705 break; /* No more left to read */
707 /* Send this buffer and go read some more */
709 if (!start_in_transfer(common, bh))
710 /* Don't know what to do if common->fsg is NULL */
712 common->next_buffhd_to_fill = bh->next;
715 return -EIO; /* No default reply */
719 /*-------------------------------------------------------------------------*/
721 static int do_write(struct fsg_common *common)
723 struct fsg_lun *curlun = common->curlun;
725 struct fsg_buffhd *bh;
727 u32 amount_left_to_req, amount_left_to_write;
728 loff_t usb_offset, file_offset, file_offset_tmp;
734 curlun->sense_data = SS_WRITE_PROTECTED;
737 spin_lock(&curlun->filp->f_lock);
738 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
739 spin_unlock(&curlun->filp->f_lock);
742 * Get the starting Logical Block Address and check that it's
745 if (common->cmnd[0] == WRITE_6)
746 lba = get_unaligned_be24(&common->cmnd[1]);
748 if (common->cmnd[0] == WRITE_16)
749 lba = get_unaligned_be64(&common->cmnd[2]);
750 else /* WRITE_10 or WRITE_12 */
751 lba = get_unaligned_be32(&common->cmnd[2]);
754 * We allow DPO (Disable Page Out = don't save data in the
755 * cache) and FUA (Force Unit Access = write directly to the
756 * medium). We don't implement DPO; we implement FUA by
757 * performing synchronous output.
759 if (common->cmnd[1] & ~0x18) {
760 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
763 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
764 spin_lock(&curlun->filp->f_lock);
765 curlun->filp->f_flags |= O_SYNC;
766 spin_unlock(&curlun->filp->f_lock);
769 if (lba >= curlun->num_sectors) {
770 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
774 /* Carry out the file writes */
776 file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
777 amount_left_to_req = common->data_size_from_cmnd;
778 amount_left_to_write = common->data_size_from_cmnd;
780 while (amount_left_to_write > 0) {
782 /* Queue a request for more data from the host */
783 bh = common->next_buffhd_to_fill;
784 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
787 * Figure out how much we want to get:
788 * Try to get the remaining amount,
789 * but not more than the buffer size.
791 amount = min(amount_left_to_req, FSG_BUFLEN);
793 /* Beyond the end of the backing file? */
794 if (usb_offset >= curlun->file_length) {
797 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
798 curlun->sense_data_info =
799 usb_offset >> curlun->blkbits;
800 curlun->info_valid = 1;
804 /* Get the next buffer */
805 usb_offset += amount;
806 common->usb_amount_left -= amount;
807 amount_left_to_req -= amount;
808 if (amount_left_to_req == 0)
812 * Except at the end of the transfer, amount will be
813 * equal to the buffer size, which is divisible by
814 * the bulk-out maxpacket size.
816 set_bulk_out_req_length(common, bh, amount);
817 if (!start_out_transfer(common, bh))
818 /* Dunno what to do if common->fsg is NULL */
820 common->next_buffhd_to_fill = bh->next;
824 /* Write the received data to the backing file */
825 bh = common->next_buffhd_to_drain;
826 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
827 break; /* We stopped early */
829 /* Wait for the data to be received */
830 rc = sleep_thread(common, false, bh);
834 common->next_buffhd_to_drain = bh->next;
835 bh->state = BUF_STATE_EMPTY;
837 /* Did something go wrong with the transfer? */
838 if (bh->outreq->status != 0) {
839 curlun->sense_data = SS_COMMUNICATION_FAILURE;
840 curlun->sense_data_info =
841 file_offset >> curlun->blkbits;
842 curlun->info_valid = 1;
846 amount = bh->outreq->actual;
847 if (curlun->file_length - file_offset < amount) {
848 LERROR(curlun, "write %u @ %llu beyond end %llu\n",
849 amount, (unsigned long long)file_offset,
850 (unsigned long long)curlun->file_length);
851 amount = curlun->file_length - file_offset;
855 * Don't accept excess data. The spec doesn't say
856 * what to do in this case. We'll ignore the error.
858 amount = min(amount, bh->bulk_out_intended_length);
860 /* Don't write a partial block */
861 amount = round_down(amount, curlun->blksize);
865 /* Perform the write */
866 file_offset_tmp = file_offset;
867 nwritten = kernel_write(curlun->filp, bh->buf, amount,
869 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
870 (unsigned long long)file_offset, (int)nwritten);
871 if (signal_pending(current))
872 return -EINTR; /* Interrupted! */
875 LDBG(curlun, "error in file write: %d\n",
878 } else if (nwritten < amount) {
879 LDBG(curlun, "partial file write: %d/%u\n",
880 (int) nwritten, amount);
881 nwritten = round_down(nwritten, curlun->blksize);
883 file_offset += nwritten;
884 amount_left_to_write -= nwritten;
885 common->residue -= nwritten;
887 /* If an error occurred, report it and its position */
888 if (nwritten < amount) {
889 curlun->sense_data = SS_WRITE_ERROR;
890 curlun->sense_data_info =
891 file_offset >> curlun->blkbits;
892 curlun->info_valid = 1;
897 /* Did the host decide to stop early? */
898 if (bh->outreq->actual < bh->bulk_out_intended_length) {
899 common->short_packet_received = 1;
904 return -EIO; /* No default reply */
908 /*-------------------------------------------------------------------------*/
910 static int do_synchronize_cache(struct fsg_common *common)
912 struct fsg_lun *curlun = common->curlun;
915 /* We ignore the requested LBA and write out all file's
916 * dirty data buffers. */
917 rc = fsg_lun_fsync_sub(curlun);
919 curlun->sense_data = SS_WRITE_ERROR;
924 /*-------------------------------------------------------------------------*/
926 static void invalidate_sub(struct fsg_lun *curlun)
928 struct file *filp = curlun->filp;
929 struct inode *inode = file_inode(filp);
932 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
933 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
936 static int do_verify(struct fsg_common *common)
938 struct fsg_lun *curlun = common->curlun;
940 u32 verification_length;
941 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
942 loff_t file_offset, file_offset_tmp;
948 * Get the starting Logical Block Address and check that it's
951 lba = get_unaligned_be32(&common->cmnd[2]);
952 if (lba >= curlun->num_sectors) {
953 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
958 * We allow DPO (Disable Page Out = don't save data in the
959 * cache) but we don't implement it.
961 if (common->cmnd[1] & ~0x10) {
962 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
966 verification_length = get_unaligned_be16(&common->cmnd[7]);
967 if (unlikely(verification_length == 0))
968 return -EIO; /* No default reply */
970 /* Prepare to carry out the file verify */
971 amount_left = verification_length << curlun->blkbits;
972 file_offset = ((loff_t) lba) << curlun->blkbits;
974 /* Write out all the dirty buffers before invalidating them */
975 fsg_lun_fsync_sub(curlun);
976 if (signal_pending(current))
979 invalidate_sub(curlun);
980 if (signal_pending(current))
983 /* Just try to read the requested blocks */
984 while (amount_left > 0) {
986 * Figure out how much we need to read:
987 * Try to read the remaining amount, but not more than
989 * And don't try to read past the end of the file.
991 amount = min(amount_left, FSG_BUFLEN);
992 amount = min((loff_t)amount,
993 curlun->file_length - file_offset);
996 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
997 curlun->sense_data_info =
998 file_offset >> curlun->blkbits;
999 curlun->info_valid = 1;
1003 /* Perform the read */
1004 file_offset_tmp = file_offset;
1005 nread = kernel_read(curlun->filp, bh->buf, amount,
1007 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1008 (unsigned long long) file_offset,
1010 if (signal_pending(current))
1014 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1016 } else if (nread < amount) {
1017 LDBG(curlun, "partial file verify: %d/%u\n",
1018 (int)nread, amount);
1019 nread = round_down(nread, curlun->blksize);
1022 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1023 curlun->sense_data_info =
1024 file_offset >> curlun->blkbits;
1025 curlun->info_valid = 1;
1028 file_offset += nread;
1029 amount_left -= nread;
1035 /*-------------------------------------------------------------------------*/
1037 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1039 struct fsg_lun *curlun = common->curlun;
1040 u8 *buf = (u8 *) bh->buf;
1042 if (!curlun) { /* Unsupported LUNs are okay */
1043 common->bad_lun_okay = 1;
1045 buf[0] = TYPE_NO_LUN; /* Unsupported, no device-type */
1046 buf[4] = 31; /* Additional length */
1050 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1051 buf[1] = curlun->removable ? 0x80 : 0;
1052 buf[2] = 2; /* ANSI SCSI level 2 */
1053 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1054 buf[4] = 31; /* Additional length */
1055 buf[5] = 0; /* No special options */
1058 if (curlun->inquiry_string[0])
1059 memcpy(buf + 8, curlun->inquiry_string,
1060 sizeof(curlun->inquiry_string));
1062 memcpy(buf + 8, common->inquiry_string,
1063 sizeof(common->inquiry_string));
1067 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1069 struct fsg_lun *curlun = common->curlun;
1070 u8 *buf = (u8 *) bh->buf;
1075 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1077 * If a REQUEST SENSE command is received from an initiator
1078 * with a pending unit attention condition (before the target
1079 * generates the contingent allegiance condition), then the
1080 * target shall either:
1081 * a) report any pending sense data and preserve the unit
1082 * attention condition on the logical unit, or,
1083 * b) report the unit attention condition, may discard any
1084 * pending sense data, and clear the unit attention
1085 * condition on the logical unit for that initiator.
1087 * FSG normally uses option a); enable this code to use option b).
1090 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1091 curlun->sense_data = curlun->unit_attention_data;
1092 curlun->unit_attention_data = SS_NO_SENSE;
1096 if (!curlun) { /* Unsupported LUNs are okay */
1097 common->bad_lun_okay = 1;
1098 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1102 sd = curlun->sense_data;
1103 sdinfo = curlun->sense_data_info;
1104 valid = curlun->info_valid << 7;
1105 curlun->sense_data = SS_NO_SENSE;
1106 curlun->sense_data_info = 0;
1107 curlun->info_valid = 0;
1111 buf[0] = valid | 0x70; /* Valid, current error */
1113 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1114 buf[7] = 18 - 8; /* Additional sense length */
1120 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1122 struct fsg_lun *curlun = common->curlun;
1123 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1124 int pmi = common->cmnd[8];
1125 u8 *buf = (u8 *)bh->buf;
1128 /* Check the PMI and LBA fields */
1129 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1130 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1134 if (curlun->num_sectors < 0x100000000ULL)
1135 max_lba = curlun->num_sectors - 1;
1137 max_lba = 0xffffffff;
1138 put_unaligned_be32(max_lba, &buf[0]); /* Max logical block */
1139 put_unaligned_be32(curlun->blksize, &buf[4]); /* Block length */
1143 static int do_read_capacity_16(struct fsg_common *common, struct fsg_buffhd *bh)
1145 struct fsg_lun *curlun = common->curlun;
1146 u64 lba = get_unaligned_be64(&common->cmnd[2]);
1147 int pmi = common->cmnd[14];
1148 u8 *buf = (u8 *)bh->buf;
1150 /* Check the PMI and LBA fields */
1151 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1152 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1156 put_unaligned_be64(curlun->num_sectors - 1, &buf[0]);
1157 /* Max logical block */
1158 put_unaligned_be32(curlun->blksize, &buf[8]); /* Block length */
1160 /* It is safe to keep other fields zeroed */
1161 memset(&buf[12], 0, 32 - 12);
1165 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1167 struct fsg_lun *curlun = common->curlun;
1168 int msf = common->cmnd[1] & 0x02;
1169 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1170 u8 *buf = (u8 *)bh->buf;
1172 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1173 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1176 if (lba >= curlun->num_sectors) {
1177 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1182 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1183 store_cdrom_address(&buf[4], msf, lba);
1187 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1189 struct fsg_lun *curlun = common->curlun;
1190 int msf = common->cmnd[1] & 0x02;
1191 int start_track = common->cmnd[6];
1192 u8 *buf = (u8 *)bh->buf;
1196 format = common->cmnd[2] & 0xf;
1198 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1199 (start_track > 1 && format != 0x1)) {
1200 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1205 * Check if CDB is old style SFF-8020i
1206 * i.e. format is in 2 MSBs of byte 9
1207 * Mac OS-X host sends us this.
1210 format = (common->cmnd[9] >> 6) & 0x3;
1213 case 0: /* Formatted TOC */
1214 case 1: /* Multi-session info */
1215 len = 4 + 2*8; /* 4 byte header + 2 descriptors */
1216 memset(buf, 0, len);
1217 buf[1] = len - 2; /* TOC Length excludes length field */
1218 buf[2] = 1; /* First track number */
1219 buf[3] = 1; /* Last track number */
1220 buf[5] = 0x16; /* Data track, copying allowed */
1221 buf[6] = 0x01; /* Only track is number 1 */
1222 store_cdrom_address(&buf[8], msf, 0);
1224 buf[13] = 0x16; /* Lead-out track is data */
1225 buf[14] = 0xAA; /* Lead-out track number */
1226 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1231 len = 4 + 3*11; /* 4 byte header + 3 descriptors */
1232 memset(buf, 0, len); /* Header + A0, A1 & A2 descriptors */
1233 buf[1] = len - 2; /* TOC Length excludes length field */
1234 buf[2] = 1; /* First complete session */
1235 buf[3] = 1; /* Last complete session */
1238 /* fill in A0, A1 and A2 points */
1239 for (i = 0; i < 3; i++) {
1240 buf[0] = 1; /* Session number */
1241 buf[1] = 0x16; /* Data track, copying allowed */
1242 /* 2 - Track number 0 -> TOC */
1243 buf[3] = 0xA0 + i; /* A0, A1, A2 point */
1244 /* 4, 5, 6 - Min, sec, frame is zero */
1245 buf[8] = 1; /* Pmin: last track number */
1246 buf += 11; /* go to next track descriptor */
1248 buf -= 11; /* go back to A2 descriptor */
1250 /* For A2, 7, 8, 9, 10 - zero, Pmin, Psec, Pframe of Lead out */
1251 store_cdrom_address(&buf[7], msf, curlun->num_sectors);
1255 /* PMA, ATIP, CD-TEXT not supported/required */
1256 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1261 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1263 struct fsg_lun *curlun = common->curlun;
1264 int mscmnd = common->cmnd[0];
1265 u8 *buf = (u8 *) bh->buf;
1268 int changeable_values, all_pages;
1272 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1273 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1276 pc = common->cmnd[2] >> 6;
1277 page_code = common->cmnd[2] & 0x3f;
1279 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1282 changeable_values = (pc == 1);
1283 all_pages = (page_code == 0x3f);
1286 * Write the mode parameter header. Fixed values are: default
1287 * medium type, no cache control (DPOFUA), and no block descriptors.
1288 * The only variable value is the WriteProtect bit. We will fill in
1289 * the mode data length later.
1292 if (mscmnd == MODE_SENSE) {
1293 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1296 } else { /* MODE_SENSE_10 */
1297 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1299 limit = 65535; /* Should really be FSG_BUFLEN */
1302 /* No block descriptors */
1305 * The mode pages, in numerical order. The only page we support
1306 * is the Caching page.
1308 if (page_code == 0x08 || all_pages) {
1310 buf[0] = 0x08; /* Page code */
1311 buf[1] = 10; /* Page length */
1312 memset(buf+2, 0, 10); /* None of the fields are changeable */
1314 if (!changeable_values) {
1315 buf[2] = 0x04; /* Write cache enable, */
1316 /* Read cache not disabled */
1317 /* No cache retention priorities */
1318 put_unaligned_be16(0xffff, &buf[4]);
1319 /* Don't disable prefetch */
1320 /* Minimum prefetch = 0 */
1321 put_unaligned_be16(0xffff, &buf[8]);
1322 /* Maximum prefetch */
1323 put_unaligned_be16(0xffff, &buf[10]);
1324 /* Maximum prefetch ceiling */
1330 * Check that a valid page was requested and the mode data length
1334 if (!valid_page || len > limit) {
1335 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1339 /* Store the mode data length */
1340 if (mscmnd == MODE_SENSE)
1343 put_unaligned_be16(len - 2, buf0);
1347 static int do_start_stop(struct fsg_common *common)
1349 struct fsg_lun *curlun = common->curlun;
1354 } else if (!curlun->removable) {
1355 curlun->sense_data = SS_INVALID_COMMAND;
1357 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1358 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1359 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1363 loej = common->cmnd[4] & 0x02;
1364 start = common->cmnd[4] & 0x01;
1367 * Our emulation doesn't support mounting; the medium is
1368 * available for use as soon as it is loaded.
1371 if (!fsg_lun_is_open(curlun)) {
1372 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1378 /* Are we allowed to unload the media? */
1379 if (curlun->prevent_medium_removal) {
1380 LDBG(curlun, "unload attempt prevented\n");
1381 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1388 up_read(&common->filesem);
1389 down_write(&common->filesem);
1390 fsg_lun_close(curlun);
1391 up_write(&common->filesem);
1392 down_read(&common->filesem);
1397 static int do_prevent_allow(struct fsg_common *common)
1399 struct fsg_lun *curlun = common->curlun;
1402 if (!common->curlun) {
1404 } else if (!common->curlun->removable) {
1405 common->curlun->sense_data = SS_INVALID_COMMAND;
1409 prevent = common->cmnd[4] & 0x01;
1410 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1411 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1415 if (curlun->prevent_medium_removal && !prevent)
1416 fsg_lun_fsync_sub(curlun);
1417 curlun->prevent_medium_removal = prevent;
1421 static int do_read_format_capacities(struct fsg_common *common,
1422 struct fsg_buffhd *bh)
1424 struct fsg_lun *curlun = common->curlun;
1425 u8 *buf = (u8 *) bh->buf;
1427 buf[0] = buf[1] = buf[2] = 0;
1428 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1431 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1432 /* Number of blocks */
1433 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1434 buf[4] = 0x02; /* Current capacity */
1438 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1440 struct fsg_lun *curlun = common->curlun;
1442 /* We don't support MODE SELECT */
1444 curlun->sense_data = SS_INVALID_COMMAND;
1449 /*-------------------------------------------------------------------------*/
1451 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1455 rc = fsg_set_halt(fsg, fsg->bulk_in);
1457 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1459 if (rc != -EAGAIN) {
1460 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1465 /* Wait for a short time and then try again */
1466 if (msleep_interruptible(100) != 0)
1468 rc = usb_ep_set_halt(fsg->bulk_in);
1473 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1477 DBG(fsg, "bulk-in set wedge\n");
1478 rc = usb_ep_set_wedge(fsg->bulk_in);
1480 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1482 if (rc != -EAGAIN) {
1483 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1488 /* Wait for a short time and then try again */
1489 if (msleep_interruptible(100) != 0)
1491 rc = usb_ep_set_wedge(fsg->bulk_in);
1496 static int throw_away_data(struct fsg_common *common)
1498 struct fsg_buffhd *bh, *bh2;
1502 for (bh = common->next_buffhd_to_drain;
1503 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1504 bh = common->next_buffhd_to_drain) {
1506 /* Try to submit another request if we need one */
1507 bh2 = common->next_buffhd_to_fill;
1508 if (bh2->state == BUF_STATE_EMPTY &&
1509 common->usb_amount_left > 0) {
1510 amount = min(common->usb_amount_left, FSG_BUFLEN);
1513 * Except at the end of the transfer, amount will be
1514 * equal to the buffer size, which is divisible by
1515 * the bulk-out maxpacket size.
1517 set_bulk_out_req_length(common, bh2, amount);
1518 if (!start_out_transfer(common, bh2))
1519 /* Dunno what to do if common->fsg is NULL */
1521 common->next_buffhd_to_fill = bh2->next;
1522 common->usb_amount_left -= amount;
1526 /* Wait for the data to be received */
1527 rc = sleep_thread(common, false, bh);
1531 /* Throw away the data in a filled buffer */
1532 bh->state = BUF_STATE_EMPTY;
1533 common->next_buffhd_to_drain = bh->next;
1535 /* A short packet or an error ends everything */
1536 if (bh->outreq->actual < bh->bulk_out_intended_length ||
1537 bh->outreq->status != 0) {
1538 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1545 static int finish_reply(struct fsg_common *common)
1547 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1550 switch (common->data_dir) {
1552 break; /* Nothing to send */
1555 * If we don't know whether the host wants to read or write,
1556 * this must be CB or CBI with an unknown command. We mustn't
1557 * try to send or receive any data. So stall both bulk pipes
1558 * if we can and wait for a reset.
1560 case DATA_DIR_UNKNOWN:
1561 if (!common->can_stall) {
1563 } else if (fsg_is_set(common)) {
1564 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1565 rc = halt_bulk_in_endpoint(common->fsg);
1567 /* Don't know what to do if common->fsg is NULL */
1572 /* All but the last buffer of data must have already been sent */
1573 case DATA_DIR_TO_HOST:
1574 if (common->data_size == 0) {
1575 /* Nothing to send */
1577 /* Don't know what to do if common->fsg is NULL */
1578 } else if (!fsg_is_set(common)) {
1581 /* If there's no residue, simply send the last buffer */
1582 } else if (common->residue == 0) {
1583 bh->inreq->zero = 0;
1584 if (!start_in_transfer(common, bh))
1586 common->next_buffhd_to_fill = bh->next;
1589 * For Bulk-only, mark the end of the data with a short
1590 * packet. If we are allowed to stall, halt the bulk-in
1591 * endpoint. (Note: This violates the Bulk-Only Transport
1592 * specification, which requires us to pad the data if we
1593 * don't halt the endpoint. Presumably nobody will mind.)
1596 bh->inreq->zero = 1;
1597 if (!start_in_transfer(common, bh))
1599 common->next_buffhd_to_fill = bh->next;
1600 if (common->can_stall)
1601 rc = halt_bulk_in_endpoint(common->fsg);
1606 * We have processed all we want from the data the host has sent.
1607 * There may still be outstanding bulk-out requests.
1609 case DATA_DIR_FROM_HOST:
1610 if (common->residue == 0) {
1611 /* Nothing to receive */
1613 /* Did the host stop sending unexpectedly early? */
1614 } else if (common->short_packet_received) {
1615 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1619 * We haven't processed all the incoming data. Even though
1620 * we may be allowed to stall, doing so would cause a race.
1621 * The controller may already have ACK'ed all the remaining
1622 * bulk-out packets, in which case the host wouldn't see a
1623 * STALL. Not realizing the endpoint was halted, it wouldn't
1624 * clear the halt -- leading to problems later on.
1627 } else if (common->can_stall) {
1628 if (fsg_is_set(common))
1629 fsg_set_halt(common->fsg,
1630 common->fsg->bulk_out);
1631 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1636 * We can't stall. Read in the excess data and throw it
1640 rc = throw_away_data(common);
1647 static void send_status(struct fsg_common *common)
1649 struct fsg_lun *curlun = common->curlun;
1650 struct fsg_buffhd *bh;
1651 struct bulk_cs_wrap *csw;
1653 u8 status = US_BULK_STAT_OK;
1656 /* Wait for the next buffer to become available */
1657 bh = common->next_buffhd_to_fill;
1658 rc = sleep_thread(common, false, bh);
1663 sd = curlun->sense_data;
1664 sdinfo = curlun->sense_data_info;
1665 } else if (common->bad_lun_okay)
1668 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1670 if (common->phase_error) {
1671 DBG(common, "sending phase-error status\n");
1672 status = US_BULK_STAT_PHASE;
1673 sd = SS_INVALID_COMMAND;
1674 } else if (sd != SS_NO_SENSE) {
1675 DBG(common, "sending command-failure status\n");
1676 status = US_BULK_STAT_FAIL;
1677 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1679 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1682 /* Store and send the Bulk-only CSW */
1683 csw = (void *)bh->buf;
1685 csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
1686 csw->Tag = common->tag;
1687 csw->Residue = cpu_to_le32(common->residue);
1688 csw->Status = status;
1690 bh->inreq->length = US_BULK_CS_WRAP_LEN;
1691 bh->inreq->zero = 0;
1692 if (!start_in_transfer(common, bh))
1693 /* Don't know what to do if common->fsg is NULL */
1696 common->next_buffhd_to_fill = bh->next;
1701 /*-------------------------------------------------------------------------*/
1704 * Check whether the command is properly formed and whether its data size
1705 * and direction agree with the values we already have.
1707 static int check_command(struct fsg_common *common, int cmnd_size,
1708 enum data_direction data_dir, unsigned int mask,
1709 int needs_medium, const char *name)
1712 unsigned int lun = common->cmnd[1] >> 5;
1713 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1715 struct fsg_lun *curlun;
1718 if (common->data_dir != DATA_DIR_UNKNOWN)
1719 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1721 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1722 name, cmnd_size, dirletter[(int) data_dir],
1723 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1726 * We can't reply at all until we know the correct data direction
1729 if (common->data_size_from_cmnd == 0)
1730 data_dir = DATA_DIR_NONE;
1731 if (common->data_size < common->data_size_from_cmnd) {
1733 * Host data size < Device data size is a phase error.
1734 * Carry out the command, but only transfer as much as
1737 common->data_size_from_cmnd = common->data_size;
1738 common->phase_error = 1;
1740 common->residue = common->data_size;
1741 common->usb_amount_left = common->data_size;
1743 /* Conflicting data directions is a phase error */
1744 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1745 common->phase_error = 1;
1749 /* Verify the length of the command itself */
1750 if (cmnd_size != common->cmnd_size) {
1753 * Special case workaround: There are plenty of buggy SCSI
1754 * implementations. Many have issues with cbw->Length
1755 * field passing a wrong command size. For those cases we
1756 * always try to work around the problem by using the length
1757 * sent by the host side provided it is at least as large
1758 * as the correct command length.
1759 * Examples of such cases would be MS-Windows, which issues
1760 * REQUEST SENSE with cbw->Length == 12 where it should
1761 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1762 * REQUEST SENSE with cbw->Length == 10 where it should
1765 if (cmnd_size <= common->cmnd_size) {
1766 DBG(common, "%s is buggy! Expected length %d "
1767 "but we got %d\n", name,
1768 cmnd_size, common->cmnd_size);
1769 cmnd_size = common->cmnd_size;
1771 common->phase_error = 1;
1776 /* Check that the LUN values are consistent */
1777 if (common->lun != lun)
1778 DBG(common, "using LUN %u from CBW, not LUN %u from CDB\n",
1782 curlun = common->curlun;
1784 if (common->cmnd[0] != REQUEST_SENSE) {
1785 curlun->sense_data = SS_NO_SENSE;
1786 curlun->sense_data_info = 0;
1787 curlun->info_valid = 0;
1790 common->bad_lun_okay = 0;
1793 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1794 * to use unsupported LUNs; all others may not.
1796 if (common->cmnd[0] != INQUIRY &&
1797 common->cmnd[0] != REQUEST_SENSE) {
1798 DBG(common, "unsupported LUN %u\n", common->lun);
1804 * If a unit attention condition exists, only INQUIRY and
1805 * REQUEST SENSE commands are allowed; anything else must fail.
1807 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1808 common->cmnd[0] != INQUIRY &&
1809 common->cmnd[0] != REQUEST_SENSE) {
1810 curlun->sense_data = curlun->unit_attention_data;
1811 curlun->unit_attention_data = SS_NO_SENSE;
1815 /* Check that only command bytes listed in the mask are non-zero */
1816 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1817 for (i = 1; i < cmnd_size; ++i) {
1818 if (common->cmnd[i] && !(mask & (1 << i))) {
1820 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1825 /* If the medium isn't mounted and the command needs to access
1826 * it, return an error. */
1827 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1828 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1835 /* wrapper of check_command for data size in blocks handling */
1836 static int check_command_size_in_blocks(struct fsg_common *common,
1837 int cmnd_size, enum data_direction data_dir,
1838 unsigned int mask, int needs_medium, const char *name)
1841 common->data_size_from_cmnd <<= common->curlun->blkbits;
1842 return check_command(common, cmnd_size, data_dir,
1843 mask, needs_medium, name);
1846 static int do_scsi_command(struct fsg_common *common)
1848 struct fsg_buffhd *bh;
1850 int reply = -EINVAL;
1852 static char unknown[16];
1856 /* Wait for the next buffer to become available for data or status */
1857 bh = common->next_buffhd_to_fill;
1858 common->next_buffhd_to_drain = bh;
1859 rc = sleep_thread(common, false, bh);
1863 common->phase_error = 0;
1864 common->short_packet_received = 0;
1866 down_read(&common->filesem); /* We're using the backing file */
1867 switch (common->cmnd[0]) {
1870 common->data_size_from_cmnd = common->cmnd[4];
1871 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1875 reply = do_inquiry(common, bh);
1879 common->data_size_from_cmnd = common->cmnd[4];
1880 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1884 reply = do_mode_select(common, bh);
1887 case MODE_SELECT_10:
1888 common->data_size_from_cmnd =
1889 get_unaligned_be16(&common->cmnd[7]);
1890 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1894 reply = do_mode_select(common, bh);
1898 common->data_size_from_cmnd = common->cmnd[4];
1899 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1900 (1<<1) | (1<<2) | (1<<4), 0,
1903 reply = do_mode_sense(common, bh);
1907 common->data_size_from_cmnd =
1908 get_unaligned_be16(&common->cmnd[7]);
1909 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1910 (1<<1) | (1<<2) | (3<<7), 0,
1913 reply = do_mode_sense(common, bh);
1916 case ALLOW_MEDIUM_REMOVAL:
1917 common->data_size_from_cmnd = 0;
1918 reply = check_command(common, 6, DATA_DIR_NONE,
1920 "PREVENT-ALLOW MEDIUM REMOVAL");
1922 reply = do_prevent_allow(common);
1926 i = common->cmnd[4];
1927 common->data_size_from_cmnd = (i == 0) ? 256 : i;
1928 reply = check_command_size_in_blocks(common, 6,
1933 reply = do_read(common);
1937 common->data_size_from_cmnd =
1938 get_unaligned_be16(&common->cmnd[7]);
1939 reply = check_command_size_in_blocks(common, 10,
1941 (1<<1) | (0xf<<2) | (3<<7), 1,
1944 reply = do_read(common);
1948 common->data_size_from_cmnd =
1949 get_unaligned_be32(&common->cmnd[6]);
1950 reply = check_command_size_in_blocks(common, 12,
1952 (1<<1) | (0xf<<2) | (0xf<<6), 1,
1955 reply = do_read(common);
1959 common->data_size_from_cmnd =
1960 get_unaligned_be32(&common->cmnd[10]);
1961 reply = check_command_size_in_blocks(common, 16,
1963 (1<<1) | (0xff<<2) | (0xf<<10), 1,
1966 reply = do_read(common);
1970 common->data_size_from_cmnd = 8;
1971 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1972 (0xf<<2) | (1<<8), 1,
1975 reply = do_read_capacity(common, bh);
1979 if (!common->curlun || !common->curlun->cdrom)
1981 common->data_size_from_cmnd =
1982 get_unaligned_be16(&common->cmnd[7]);
1983 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1984 (3<<7) | (0x1f<<1), 1,
1987 reply = do_read_header(common, bh);
1991 if (!common->curlun || !common->curlun->cdrom)
1993 common->data_size_from_cmnd =
1994 get_unaligned_be16(&common->cmnd[7]);
1995 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1996 (0xf<<6) | (3<<1), 1,
1999 reply = do_read_toc(common, bh);
2002 case READ_FORMAT_CAPACITIES:
2003 common->data_size_from_cmnd =
2004 get_unaligned_be16(&common->cmnd[7]);
2005 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2007 "READ FORMAT CAPACITIES");
2009 reply = do_read_format_capacities(common, bh);
2013 common->data_size_from_cmnd = common->cmnd[4];
2014 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2018 reply = do_request_sense(common, bh);
2021 case SERVICE_ACTION_IN_16:
2022 switch (common->cmnd[1] & 0x1f) {
2024 case SAI_READ_CAPACITY_16:
2025 common->data_size_from_cmnd =
2026 get_unaligned_be32(&common->cmnd[10]);
2027 reply = check_command(common, 16, DATA_DIR_TO_HOST,
2028 (1<<1) | (0xff<<2) | (0xf<<10) |
2030 "READ CAPACITY(16)");
2032 reply = do_read_capacity_16(common, bh);
2041 common->data_size_from_cmnd = 0;
2042 reply = check_command(common, 6, DATA_DIR_NONE,
2046 reply = do_start_stop(common);
2049 case SYNCHRONIZE_CACHE:
2050 common->data_size_from_cmnd = 0;
2051 reply = check_command(common, 10, DATA_DIR_NONE,
2052 (0xf<<2) | (3<<7), 1,
2053 "SYNCHRONIZE CACHE");
2055 reply = do_synchronize_cache(common);
2058 case TEST_UNIT_READY:
2059 common->data_size_from_cmnd = 0;
2060 reply = check_command(common, 6, DATA_DIR_NONE,
2066 * Although optional, this command is used by MS-Windows. We
2067 * support a minimal version: BytChk must be 0.
2070 common->data_size_from_cmnd = 0;
2071 reply = check_command(common, 10, DATA_DIR_NONE,
2072 (1<<1) | (0xf<<2) | (3<<7), 1,
2075 reply = do_verify(common);
2079 i = common->cmnd[4];
2080 common->data_size_from_cmnd = (i == 0) ? 256 : i;
2081 reply = check_command_size_in_blocks(common, 6,
2086 reply = do_write(common);
2090 common->data_size_from_cmnd =
2091 get_unaligned_be16(&common->cmnd[7]);
2092 reply = check_command_size_in_blocks(common, 10,
2094 (1<<1) | (0xf<<2) | (3<<7), 1,
2097 reply = do_write(common);
2101 common->data_size_from_cmnd =
2102 get_unaligned_be32(&common->cmnd[6]);
2103 reply = check_command_size_in_blocks(common, 12,
2105 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2108 reply = do_write(common);
2112 common->data_size_from_cmnd =
2113 get_unaligned_be32(&common->cmnd[10]);
2114 reply = check_command_size_in_blocks(common, 16,
2116 (1<<1) | (0xff<<2) | (0xf<<10), 1,
2119 reply = do_write(common);
2123 * Some mandatory commands that we recognize but don't implement.
2124 * They don't mean much in this setting. It's left as an exercise
2125 * for anyone interested to implement RESERVE and RELEASE in terms
2131 case SEND_DIAGNOSTIC:
2135 common->data_size_from_cmnd = 0;
2136 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2137 reply = check_command(common, common->cmnd_size,
2138 DATA_DIR_UNKNOWN, ~0, 0, unknown);
2140 common->curlun->sense_data = SS_INVALID_COMMAND;
2145 up_read(&common->filesem);
2147 if (reply == -EINTR || signal_pending(current))
2150 /* Set up the single reply buffer for finish_reply() */
2151 if (reply == -EINVAL)
2152 reply = 0; /* Error reply length */
2153 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2154 reply = min((u32)reply, common->data_size_from_cmnd);
2155 bh->inreq->length = reply;
2156 bh->state = BUF_STATE_FULL;
2157 common->residue -= reply;
2158 } /* Otherwise it's already set */
2164 /*-------------------------------------------------------------------------*/
2166 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2168 struct usb_request *req = bh->outreq;
2169 struct bulk_cb_wrap *cbw = req->buf;
2170 struct fsg_common *common = fsg->common;
2172 /* Was this a real packet? Should it be ignored? */
2173 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2176 /* Is the CBW valid? */
2177 if (req->actual != US_BULK_CB_WRAP_LEN ||
2178 cbw->Signature != cpu_to_le32(
2180 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2182 le32_to_cpu(cbw->Signature));
2185 * The Bulk-only spec says we MUST stall the IN endpoint
2186 * (6.6.1), so it's unavoidable. It also says we must
2187 * retain this state until the next reset, but there's
2188 * no way to tell the controller driver it should ignore
2189 * Clear-Feature(HALT) requests.
2191 * We aren't required to halt the OUT endpoint; instead
2192 * we can simply accept and discard any data received
2193 * until the next reset.
2195 wedge_bulk_in_endpoint(fsg);
2196 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2200 /* Is the CBW meaningful? */
2201 if (cbw->Lun >= ARRAY_SIZE(common->luns) ||
2202 cbw->Flags & ~US_BULK_FLAG_IN || cbw->Length <= 0 ||
2203 cbw->Length > MAX_COMMAND_SIZE) {
2204 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2206 cbw->Lun, cbw->Flags, cbw->Length);
2209 * We can do anything we want here, so let's stall the
2210 * bulk pipes if we are allowed to.
2212 if (common->can_stall) {
2213 fsg_set_halt(fsg, fsg->bulk_out);
2214 halt_bulk_in_endpoint(fsg);
2219 /* Save the command for later */
2220 common->cmnd_size = cbw->Length;
2221 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2222 if (cbw->Flags & US_BULK_FLAG_IN)
2223 common->data_dir = DATA_DIR_TO_HOST;
2225 common->data_dir = DATA_DIR_FROM_HOST;
2226 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2227 if (common->data_size == 0)
2228 common->data_dir = DATA_DIR_NONE;
2229 common->lun = cbw->Lun;
2230 if (common->lun < ARRAY_SIZE(common->luns))
2231 common->curlun = common->luns[common->lun];
2233 common->curlun = NULL;
2234 common->tag = cbw->Tag;
2238 static int get_next_command(struct fsg_common *common)
2240 struct fsg_buffhd *bh;
2243 /* Wait for the next buffer to become available */
2244 bh = common->next_buffhd_to_fill;
2245 rc = sleep_thread(common, true, bh);
2249 /* Queue a request to read a Bulk-only CBW */
2250 set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
2251 if (!start_out_transfer(common, bh))
2252 /* Don't know what to do if common->fsg is NULL */
2256 * We will drain the buffer in software, which means we
2257 * can reuse it for the next filling. No need to advance
2258 * next_buffhd_to_fill.
2261 /* Wait for the CBW to arrive */
2262 rc = sleep_thread(common, true, bh);
2266 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2267 bh->state = BUF_STATE_EMPTY;
2273 /*-------------------------------------------------------------------------*/
2275 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2276 struct usb_request **preq)
2278 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2281 ERROR(common, "can't allocate request for %s\n", ep->name);
2285 /* Reset interface setting and re-init endpoint state (toggle etc). */
2286 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2288 struct fsg_dev *fsg;
2291 if (common->running)
2292 DBG(common, "reset interface\n");
2295 /* Deallocate the requests */
2299 for (i = 0; i < common->fsg_num_buffers; ++i) {
2300 struct fsg_buffhd *bh = &common->buffhds[i];
2303 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2307 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2312 /* Disable the endpoints */
2313 if (fsg->bulk_in_enabled) {
2314 usb_ep_disable(fsg->bulk_in);
2315 fsg->bulk_in_enabled = 0;
2317 if (fsg->bulk_out_enabled) {
2318 usb_ep_disable(fsg->bulk_out);
2319 fsg->bulk_out_enabled = 0;
2323 wake_up(&common->fsg_wait);
2326 common->running = 0;
2330 common->fsg = new_fsg;
2333 /* Enable the endpoints */
2334 rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
2337 rc = usb_ep_enable(fsg->bulk_in);
2340 fsg->bulk_in->driver_data = common;
2341 fsg->bulk_in_enabled = 1;
2343 rc = config_ep_by_speed(common->gadget, &(fsg->function),
2347 rc = usb_ep_enable(fsg->bulk_out);
2350 fsg->bulk_out->driver_data = common;
2351 fsg->bulk_out_enabled = 1;
2352 common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc);
2353 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2355 /* Allocate the requests */
2356 for (i = 0; i < common->fsg_num_buffers; ++i) {
2357 struct fsg_buffhd *bh = &common->buffhds[i];
2359 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2362 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2365 bh->inreq->buf = bh->outreq->buf = bh->buf;
2366 bh->inreq->context = bh->outreq->context = bh;
2367 bh->inreq->complete = bulk_in_complete;
2368 bh->outreq->complete = bulk_out_complete;
2371 common->running = 1;
2372 for (i = 0; i < ARRAY_SIZE(common->luns); ++i)
2373 if (common->luns[i])
2374 common->luns[i]->unit_attention_data =
2380 /****************************** ALT CONFIGS ******************************/
2382 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2384 struct fsg_dev *fsg = fsg_from_func(f);
2386 __raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE, fsg);
2387 return USB_GADGET_DELAYED_STATUS;
2390 static void fsg_disable(struct usb_function *f)
2392 struct fsg_dev *fsg = fsg_from_func(f);
2394 /* Disable the endpoints */
2395 if (fsg->bulk_in_enabled) {
2396 usb_ep_disable(fsg->bulk_in);
2397 fsg->bulk_in_enabled = 0;
2399 if (fsg->bulk_out_enabled) {
2400 usb_ep_disable(fsg->bulk_out);
2401 fsg->bulk_out_enabled = 0;
2404 __raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE, NULL);
2408 /*-------------------------------------------------------------------------*/
2410 static void handle_exception(struct fsg_common *common)
2413 struct fsg_buffhd *bh;
2414 enum fsg_state old_state;
2415 struct fsg_lun *curlun;
2416 unsigned int exception_req_tag;
2417 struct fsg_dev *new_fsg;
2420 * Clear the existing signals. Anything but SIGUSR1 is converted
2421 * into a high-priority EXIT exception.
2424 int sig = kernel_dequeue_signal();
2427 if (sig != SIGUSR1) {
2428 spin_lock_irq(&common->lock);
2429 if (common->state < FSG_STATE_EXIT)
2430 DBG(common, "Main thread exiting on signal\n");
2431 common->state = FSG_STATE_EXIT;
2432 spin_unlock_irq(&common->lock);
2436 /* Cancel all the pending transfers */
2437 if (likely(common->fsg)) {
2438 for (i = 0; i < common->fsg_num_buffers; ++i) {
2439 bh = &common->buffhds[i];
2440 if (bh->state == BUF_STATE_SENDING)
2441 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2442 if (bh->state == BUF_STATE_RECEIVING)
2443 usb_ep_dequeue(common->fsg->bulk_out,
2446 /* Wait for a transfer to become idle */
2447 if (sleep_thread(common, false, bh))
2451 /* Clear out the controller's fifos */
2452 if (common->fsg->bulk_in_enabled)
2453 usb_ep_fifo_flush(common->fsg->bulk_in);
2454 if (common->fsg->bulk_out_enabled)
2455 usb_ep_fifo_flush(common->fsg->bulk_out);
2459 * Reset the I/O buffer states and pointers, the SCSI
2460 * state, and the exception. Then invoke the handler.
2462 spin_lock_irq(&common->lock);
2464 for (i = 0; i < common->fsg_num_buffers; ++i) {
2465 bh = &common->buffhds[i];
2466 bh->state = BUF_STATE_EMPTY;
2468 common->next_buffhd_to_fill = &common->buffhds[0];
2469 common->next_buffhd_to_drain = &common->buffhds[0];
2470 exception_req_tag = common->exception_req_tag;
2471 new_fsg = common->exception_arg;
2472 old_state = common->state;
2473 common->state = FSG_STATE_NORMAL;
2475 if (old_state != FSG_STATE_ABORT_BULK_OUT) {
2476 for (i = 0; i < ARRAY_SIZE(common->luns); ++i) {
2477 curlun = common->luns[i];
2480 curlun->prevent_medium_removal = 0;
2481 curlun->sense_data = SS_NO_SENSE;
2482 curlun->unit_attention_data = SS_NO_SENSE;
2483 curlun->sense_data_info = 0;
2484 curlun->info_valid = 0;
2487 spin_unlock_irq(&common->lock);
2489 /* Carry out any extra actions required for the exception */
2490 switch (old_state) {
2491 case FSG_STATE_NORMAL:
2494 case FSG_STATE_ABORT_BULK_OUT:
2495 send_status(common);
2498 case FSG_STATE_PROTOCOL_RESET:
2500 * In case we were forced against our will to halt a
2501 * bulk endpoint, clear the halt now. (The SuperH UDC
2504 if (!fsg_is_set(common))
2506 if (test_and_clear_bit(IGNORE_BULK_OUT,
2507 &common->fsg->atomic_bitflags))
2508 usb_ep_clear_halt(common->fsg->bulk_in);
2510 if (common->ep0_req_tag == exception_req_tag)
2511 ep0_queue(common); /* Complete the status stage */
2514 * Technically this should go here, but it would only be
2515 * a waste of time. Ditto for the INTERFACE_CHANGE and
2516 * CONFIG_CHANGE cases.
2518 /* for (i = 0; i < common->ARRAY_SIZE(common->luns); ++i) */
2519 /* if (common->luns[i]) */
2520 /* common->luns[i]->unit_attention_data = */
2521 /* SS_RESET_OCCURRED; */
2524 case FSG_STATE_CONFIG_CHANGE:
2525 do_set_interface(common, new_fsg);
2527 usb_composite_setup_continue(common->cdev);
2530 case FSG_STATE_EXIT:
2531 do_set_interface(common, NULL); /* Free resources */
2532 spin_lock_irq(&common->lock);
2533 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2534 spin_unlock_irq(&common->lock);
2537 case FSG_STATE_TERMINATED:
2543 /*-------------------------------------------------------------------------*/
2545 static int fsg_main_thread(void *common_)
2547 struct fsg_common *common = common_;
2551 * Allow the thread to be killed by a signal, but set the signal mask
2552 * to block everything but INT, TERM, KILL, and USR1.
2554 allow_signal(SIGINT);
2555 allow_signal(SIGTERM);
2556 allow_signal(SIGKILL);
2557 allow_signal(SIGUSR1);
2559 /* Allow the thread to be frozen */
2563 while (common->state != FSG_STATE_TERMINATED) {
2564 if (exception_in_progress(common) || signal_pending(current)) {
2565 handle_exception(common);
2569 if (!common->running) {
2570 sleep_thread(common, true, NULL);
2574 if (get_next_command(common) || exception_in_progress(common))
2576 if (do_scsi_command(common) || exception_in_progress(common))
2578 if (finish_reply(common) || exception_in_progress(common))
2580 send_status(common);
2583 spin_lock_irq(&common->lock);
2584 common->thread_task = NULL;
2585 spin_unlock_irq(&common->lock);
2587 /* Eject media from all LUNs */
2589 down_write(&common->filesem);
2590 for (i = 0; i < ARRAY_SIZE(common->luns); i++) {
2591 struct fsg_lun *curlun = common->luns[i];
2593 if (curlun && fsg_lun_is_open(curlun))
2594 fsg_lun_close(curlun);
2596 up_write(&common->filesem);
2598 /* Let fsg_unbind() know the thread has exited */
2599 kthread_complete_and_exit(&common->thread_notifier, 0);
2603 /*************************** DEVICE ATTRIBUTES ***************************/
2605 static ssize_t ro_show(struct device *dev, struct device_attribute *attr, char *buf)
2607 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2609 return fsg_show_ro(curlun, buf);
2612 static ssize_t nofua_show(struct device *dev, struct device_attribute *attr,
2615 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2617 return fsg_show_nofua(curlun, buf);
2620 static ssize_t file_show(struct device *dev, struct device_attribute *attr,
2623 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2624 struct rw_semaphore *filesem = dev_get_drvdata(dev);
2626 return fsg_show_file(curlun, filesem, buf);
2629 static ssize_t ro_store(struct device *dev, struct device_attribute *attr,
2630 const char *buf, size_t count)
2632 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2633 struct rw_semaphore *filesem = dev_get_drvdata(dev);
2635 return fsg_store_ro(curlun, filesem, buf, count);
2638 static ssize_t nofua_store(struct device *dev, struct device_attribute *attr,
2639 const char *buf, size_t count)
2641 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2643 return fsg_store_nofua(curlun, buf, count);
2646 static ssize_t file_store(struct device *dev, struct device_attribute *attr,
2647 const char *buf, size_t count)
2649 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2650 struct rw_semaphore *filesem = dev_get_drvdata(dev);
2652 return fsg_store_file(curlun, filesem, buf, count);
2655 static ssize_t forced_eject_store(struct device *dev,
2656 struct device_attribute *attr,
2657 const char *buf, size_t count)
2659 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2660 struct rw_semaphore *filesem = dev_get_drvdata(dev);
2662 return fsg_store_forced_eject(curlun, filesem, buf, count);
2665 static DEVICE_ATTR_RW(nofua);
2666 static DEVICE_ATTR_WO(forced_eject);
2669 * Mode of the ro and file attribute files will be overridden in
2670 * fsg_lun_dev_is_visible() depending on if this is a cdrom, or if it is a
2673 static DEVICE_ATTR_RW(ro);
2674 static DEVICE_ATTR_RW(file);
2676 /****************************** FSG COMMON ******************************/
2678 static void fsg_lun_release(struct device *dev)
2680 /* Nothing needs to be done */
2683 static struct fsg_common *fsg_common_setup(struct fsg_common *common)
2686 common = kzalloc(sizeof(*common), GFP_KERNEL);
2688 return ERR_PTR(-ENOMEM);
2689 common->free_storage_on_release = 1;
2691 common->free_storage_on_release = 0;
2693 init_rwsem(&common->filesem);
2694 spin_lock_init(&common->lock);
2695 init_completion(&common->thread_notifier);
2696 init_waitqueue_head(&common->io_wait);
2697 init_waitqueue_head(&common->fsg_wait);
2698 common->state = FSG_STATE_TERMINATED;
2699 memset(common->luns, 0, sizeof(common->luns));
2704 void fsg_common_set_sysfs(struct fsg_common *common, bool sysfs)
2706 common->sysfs = sysfs;
2708 EXPORT_SYMBOL_GPL(fsg_common_set_sysfs);
2710 static void _fsg_common_free_buffers(struct fsg_buffhd *buffhds, unsigned n)
2713 struct fsg_buffhd *bh = buffhds;
2722 int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n)
2724 struct fsg_buffhd *bh, *buffhds;
2727 buffhds = kcalloc(n, sizeof(*buffhds), GFP_KERNEL);
2731 /* Data buffers cyclic list */
2734 goto buffhds_first_it;
2739 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2740 if (unlikely(!bh->buf))
2745 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
2746 common->fsg_num_buffers = n;
2747 common->buffhds = buffhds;
2753 * "buf"s pointed to by heads after n - i are NULL
2754 * so releasing them won't hurt
2756 _fsg_common_free_buffers(buffhds, n);
2760 EXPORT_SYMBOL_GPL(fsg_common_set_num_buffers);
2762 void fsg_common_remove_lun(struct fsg_lun *lun)
2764 if (device_is_registered(&lun->dev))
2765 device_unregister(&lun->dev);
2769 EXPORT_SYMBOL_GPL(fsg_common_remove_lun);
2771 static void _fsg_common_remove_luns(struct fsg_common *common, int n)
2775 for (i = 0; i < n; ++i)
2776 if (common->luns[i]) {
2777 fsg_common_remove_lun(common->luns[i]);
2778 common->luns[i] = NULL;
2782 void fsg_common_remove_luns(struct fsg_common *common)
2784 _fsg_common_remove_luns(common, ARRAY_SIZE(common->luns));
2786 EXPORT_SYMBOL_GPL(fsg_common_remove_luns);
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,
2828 &dev_attr_forced_eject.attr,
2832 static umode_t fsg_lun_dev_is_visible(struct kobject *kobj,
2833 struct attribute *attr, int idx)
2835 struct device *dev = kobj_to_dev(kobj);
2836 struct fsg_lun *lun = fsg_lun_from_dev(dev);
2838 if (attr == &dev_attr_ro.attr)
2839 return lun->cdrom ? S_IRUGO : (S_IWUSR | S_IRUGO);
2840 if (attr == &dev_attr_file.attr)
2841 return lun->removable ? (S_IWUSR | S_IRUGO) : S_IRUGO;
2845 static const struct attribute_group fsg_lun_dev_group = {
2846 .attrs = fsg_lun_dev_attrs,
2847 .is_visible = fsg_lun_dev_is_visible,
2850 static const struct attribute_group *fsg_lun_dev_groups[] = {
2855 int fsg_common_create_lun(struct fsg_common *common, struct fsg_lun_config *cfg,
2856 unsigned int id, const char *name,
2857 const char **name_pfx)
2859 struct fsg_lun *lun;
2860 char *pathbuf = NULL, *p = "(no medium)";
2863 if (id >= ARRAY_SIZE(common->luns))
2866 if (common->luns[id])
2869 if (!cfg->filename && !cfg->removable) {
2870 pr_err("no file given for LUN%d\n", id);
2874 lun = kzalloc(sizeof(*lun), GFP_KERNEL);
2878 lun->name_pfx = name_pfx;
2880 lun->cdrom = !!cfg->cdrom;
2881 lun->ro = cfg->cdrom || cfg->ro;
2882 lun->initially_ro = lun->ro;
2883 lun->removable = !!cfg->removable;
2885 if (!common->sysfs) {
2886 /* we DON'T own the name!*/
2889 lun->dev.release = fsg_lun_release;
2890 lun->dev.parent = &common->gadget->dev;
2891 lun->dev.groups = fsg_lun_dev_groups;
2892 dev_set_drvdata(&lun->dev, &common->filesem);
2893 dev_set_name(&lun->dev, "%s", name);
2894 lun->name = dev_name(&lun->dev);
2896 rc = device_register(&lun->dev);
2898 pr_info("failed to register LUN%d: %d\n", id, rc);
2899 put_device(&lun->dev);
2904 common->luns[id] = lun;
2906 if (cfg->filename) {
2907 rc = fsg_lun_open(lun, cfg->filename);
2912 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2914 p = file_path(lun->filp, pathbuf, PATH_MAX);
2919 pr_info("LUN: %s%s%sfile: %s\n",
2920 lun->removable ? "removable " : "",
2921 lun->ro ? "read only " : "",
2922 lun->cdrom ? "CD-ROM " : "",
2929 if (device_is_registered(&lun->dev))
2930 device_unregister(&lun->dev);
2931 common->luns[id] = NULL;
2936 EXPORT_SYMBOL_GPL(fsg_common_create_lun);
2938 int fsg_common_create_luns(struct fsg_common *common, struct fsg_config *cfg)
2940 char buf[8]; /* enough for 100000000 different numbers, decimal */
2943 fsg_common_remove_luns(common);
2945 for (i = 0; i < cfg->nluns; ++i) {
2946 snprintf(buf, sizeof(buf), "lun%d", i);
2947 rc = fsg_common_create_lun(common, &cfg->luns[i], i, buf, NULL);
2952 pr_info("Number of LUNs=%d\n", cfg->nluns);
2957 _fsg_common_remove_luns(common, i);
2960 EXPORT_SYMBOL_GPL(fsg_common_create_luns);
2962 void fsg_common_set_inquiry_string(struct fsg_common *common, const char *vn,
2967 /* Prepare inquiryString */
2968 i = get_default_bcdDevice();
2969 snprintf(common->inquiry_string, sizeof(common->inquiry_string),
2970 "%-8s%-16s%04x", vn ?: "Linux",
2971 /* Assume product name dependent on the first LUN */
2972 pn ?: ((*common->luns)->cdrom
2974 : "File-Stor Gadget"),
2977 EXPORT_SYMBOL_GPL(fsg_common_set_inquiry_string);
2979 static void fsg_common_release(struct fsg_common *common)
2983 /* If the thread isn't already dead, tell it to exit now */
2984 if (common->state != FSG_STATE_TERMINATED) {
2985 raise_exception(common, FSG_STATE_EXIT);
2986 wait_for_completion(&common->thread_notifier);
2989 for (i = 0; i < ARRAY_SIZE(common->luns); ++i) {
2990 struct fsg_lun *lun = common->luns[i];
2994 if (device_is_registered(&lun->dev))
2995 device_unregister(&lun->dev);
2999 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
3000 if (common->free_storage_on_release)
3005 /*-------------------------------------------------------------------------*/
3007 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
3009 struct fsg_dev *fsg = fsg_from_func(f);
3010 struct fsg_common *common = fsg->common;
3011 struct usb_gadget *gadget = c->cdev->gadget;
3016 struct fsg_opts *opts;
3018 /* Don't allow to bind if we don't have at least one LUN */
3019 ret = _fsg_common_get_max_lun(common);
3021 pr_err("There should be at least one LUN.\n");
3025 opts = fsg_opts_from_func_inst(f->fi);
3026 if (!opts->no_configfs) {
3027 ret = fsg_common_set_cdev(fsg->common, c->cdev,
3028 fsg->common->can_stall);
3031 fsg_common_set_inquiry_string(fsg->common, NULL, NULL);
3034 if (!common->thread_task) {
3035 common->state = FSG_STATE_NORMAL;
3036 common->thread_task =
3037 kthread_create(fsg_main_thread, common, "file-storage");
3038 if (IS_ERR(common->thread_task)) {
3039 ret = PTR_ERR(common->thread_task);
3040 common->thread_task = NULL;
3041 common->state = FSG_STATE_TERMINATED;
3044 DBG(common, "I/O thread pid: %d\n",
3045 task_pid_nr(common->thread_task));
3046 wake_up_process(common->thread_task);
3049 fsg->gadget = gadget;
3052 i = usb_interface_id(c, f);
3055 fsg_intf_desc.bInterfaceNumber = i;
3056 fsg->interface_number = i;
3058 /* Find all the endpoints we will use */
3059 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
3064 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
3069 /* Assume endpoint addresses are the same for both speeds */
3070 fsg_hs_bulk_in_desc.bEndpointAddress =
3071 fsg_fs_bulk_in_desc.bEndpointAddress;
3072 fsg_hs_bulk_out_desc.bEndpointAddress =
3073 fsg_fs_bulk_out_desc.bEndpointAddress;
3075 /* Calculate bMaxBurst, we know packet size is 1024 */
3076 max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15);
3078 fsg_ss_bulk_in_desc.bEndpointAddress =
3079 fsg_fs_bulk_in_desc.bEndpointAddress;
3080 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
3082 fsg_ss_bulk_out_desc.bEndpointAddress =
3083 fsg_fs_bulk_out_desc.bEndpointAddress;
3084 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
3086 ret = usb_assign_descriptors(f, fsg_fs_function, fsg_hs_function,
3087 fsg_ss_function, fsg_ss_function);
3094 ERROR(fsg, "unable to autoconfigure all endpoints\n");
3097 /* terminate the thread */
3098 if (fsg->common->state != FSG_STATE_TERMINATED) {
3099 raise_exception(fsg->common, FSG_STATE_EXIT);
3100 wait_for_completion(&fsg->common->thread_notifier);
3105 /****************************** ALLOCATE FUNCTION *************************/
3107 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
3109 struct fsg_dev *fsg = fsg_from_func(f);
3110 struct fsg_common *common = fsg->common;
3112 DBG(fsg, "unbind\n");
3113 if (fsg->common->fsg == fsg) {
3114 __raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE, NULL);
3115 /* FIXME: make interruptible or killable somehow? */
3116 wait_event(common->fsg_wait, common->fsg != fsg);
3119 usb_free_all_descriptors(&fsg->function);
3122 static inline struct fsg_lun_opts *to_fsg_lun_opts(struct config_item *item)
3124 return container_of(to_config_group(item), struct fsg_lun_opts, group);
3127 static inline struct fsg_opts *to_fsg_opts(struct config_item *item)
3129 return container_of(to_config_group(item), struct fsg_opts,
3133 static void fsg_lun_attr_release(struct config_item *item)
3135 struct fsg_lun_opts *lun_opts;
3137 lun_opts = to_fsg_lun_opts(item);
3141 static struct configfs_item_operations fsg_lun_item_ops = {
3142 .release = fsg_lun_attr_release,
3145 static ssize_t fsg_lun_opts_file_show(struct config_item *item, char *page)
3147 struct fsg_lun_opts *opts = to_fsg_lun_opts(item);
3148 struct fsg_opts *fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3150 return fsg_show_file(opts->lun, &fsg_opts->common->filesem, page);
3153 static ssize_t fsg_lun_opts_file_store(struct config_item *item,
3154 const char *page, size_t len)
3156 struct fsg_lun_opts *opts = to_fsg_lun_opts(item);
3157 struct fsg_opts *fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3159 return fsg_store_file(opts->lun, &fsg_opts->common->filesem, page, len);
3162 CONFIGFS_ATTR(fsg_lun_opts_, file);
3164 static ssize_t fsg_lun_opts_ro_show(struct config_item *item, char *page)
3166 return fsg_show_ro(to_fsg_lun_opts(item)->lun, page);
3169 static ssize_t fsg_lun_opts_ro_store(struct config_item *item,
3170 const char *page, size_t len)
3172 struct fsg_lun_opts *opts = to_fsg_lun_opts(item);
3173 struct fsg_opts *fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3175 return fsg_store_ro(opts->lun, &fsg_opts->common->filesem, page, len);
3178 CONFIGFS_ATTR(fsg_lun_opts_, ro);
3180 static ssize_t fsg_lun_opts_removable_show(struct config_item *item,
3183 return fsg_show_removable(to_fsg_lun_opts(item)->lun, page);
3186 static ssize_t fsg_lun_opts_removable_store(struct config_item *item,
3187 const char *page, size_t len)
3189 return fsg_store_removable(to_fsg_lun_opts(item)->lun, page, len);
3192 CONFIGFS_ATTR(fsg_lun_opts_, removable);
3194 static ssize_t fsg_lun_opts_cdrom_show(struct config_item *item, char *page)
3196 return fsg_show_cdrom(to_fsg_lun_opts(item)->lun, page);
3199 static ssize_t fsg_lun_opts_cdrom_store(struct config_item *item,
3200 const char *page, size_t len)
3202 struct fsg_lun_opts *opts = to_fsg_lun_opts(item);
3203 struct fsg_opts *fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3205 return fsg_store_cdrom(opts->lun, &fsg_opts->common->filesem, page,
3209 CONFIGFS_ATTR(fsg_lun_opts_, cdrom);
3211 static ssize_t fsg_lun_opts_nofua_show(struct config_item *item, char *page)
3213 return fsg_show_nofua(to_fsg_lun_opts(item)->lun, page);
3216 static ssize_t fsg_lun_opts_nofua_store(struct config_item *item,
3217 const char *page, size_t len)
3219 return fsg_store_nofua(to_fsg_lun_opts(item)->lun, page, len);
3222 CONFIGFS_ATTR(fsg_lun_opts_, nofua);
3224 static ssize_t fsg_lun_opts_inquiry_string_show(struct config_item *item,
3227 return fsg_show_inquiry_string(to_fsg_lun_opts(item)->lun, page);
3230 static ssize_t fsg_lun_opts_inquiry_string_store(struct config_item *item,
3231 const char *page, size_t len)
3233 return fsg_store_inquiry_string(to_fsg_lun_opts(item)->lun, page, len);
3236 CONFIGFS_ATTR(fsg_lun_opts_, inquiry_string);
3238 static ssize_t fsg_lun_opts_forced_eject_store(struct config_item *item,
3239 const char *page, size_t len)
3241 struct fsg_lun_opts *opts = to_fsg_lun_opts(item);
3242 struct fsg_opts *fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3244 return fsg_store_forced_eject(opts->lun, &fsg_opts->common->filesem,
3248 CONFIGFS_ATTR_WO(fsg_lun_opts_, forced_eject);
3250 static struct configfs_attribute *fsg_lun_attrs[] = {
3251 &fsg_lun_opts_attr_file,
3252 &fsg_lun_opts_attr_ro,
3253 &fsg_lun_opts_attr_removable,
3254 &fsg_lun_opts_attr_cdrom,
3255 &fsg_lun_opts_attr_nofua,
3256 &fsg_lun_opts_attr_inquiry_string,
3257 &fsg_lun_opts_attr_forced_eject,
3261 static const struct config_item_type fsg_lun_type = {
3262 .ct_item_ops = &fsg_lun_item_ops,
3263 .ct_attrs = fsg_lun_attrs,
3264 .ct_owner = THIS_MODULE,
3267 static struct config_group *fsg_lun_make(struct config_group *group,
3270 struct fsg_lun_opts *opts;
3271 struct fsg_opts *fsg_opts;
3272 struct fsg_lun_config config;
3277 num_str = strchr(name, '.');
3279 pr_err("Unable to locate . in LUN.NUMBER\n");
3280 return ERR_PTR(-EINVAL);
3284 ret = kstrtou8(num_str, 0, &num);
3286 return ERR_PTR(ret);
3288 fsg_opts = to_fsg_opts(&group->cg_item);
3289 if (num >= FSG_MAX_LUNS)
3290 return ERR_PTR(-ERANGE);
3291 num = array_index_nospec(num, FSG_MAX_LUNS);
3293 mutex_lock(&fsg_opts->lock);
3294 if (fsg_opts->refcnt || fsg_opts->common->luns[num]) {
3299 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
3305 memset(&config, 0, sizeof(config));
3306 config.removable = true;
3308 ret = fsg_common_create_lun(fsg_opts->common, &config, num, name,
3309 (const char **)&group->cg_item.ci_name);
3314 opts->lun = fsg_opts->common->luns[num];
3316 mutex_unlock(&fsg_opts->lock);
3318 config_group_init_type_name(&opts->group, name, &fsg_lun_type);
3320 return &opts->group;
3322 mutex_unlock(&fsg_opts->lock);
3323 return ERR_PTR(ret);
3326 static void fsg_lun_drop(struct config_group *group, struct config_item *item)
3328 struct fsg_lun_opts *lun_opts;
3329 struct fsg_opts *fsg_opts;
3331 lun_opts = to_fsg_lun_opts(item);
3332 fsg_opts = to_fsg_opts(&group->cg_item);
3334 mutex_lock(&fsg_opts->lock);
3335 if (fsg_opts->refcnt) {
3336 struct config_item *gadget;
3338 gadget = group->cg_item.ci_parent->ci_parent;
3339 unregister_gadget_item(gadget);
3342 fsg_common_remove_lun(lun_opts->lun);
3343 fsg_opts->common->luns[lun_opts->lun_id] = NULL;
3344 lun_opts->lun_id = 0;
3345 mutex_unlock(&fsg_opts->lock);
3347 config_item_put(item);
3350 static void fsg_attr_release(struct config_item *item)
3352 struct fsg_opts *opts = to_fsg_opts(item);
3354 usb_put_function_instance(&opts->func_inst);
3357 static struct configfs_item_operations fsg_item_ops = {
3358 .release = fsg_attr_release,
3361 static ssize_t fsg_opts_stall_show(struct config_item *item, char *page)
3363 struct fsg_opts *opts = to_fsg_opts(item);
3366 mutex_lock(&opts->lock);
3367 result = sprintf(page, "%d", opts->common->can_stall);
3368 mutex_unlock(&opts->lock);
3373 static ssize_t fsg_opts_stall_store(struct config_item *item, const char *page,
3376 struct fsg_opts *opts = to_fsg_opts(item);
3380 mutex_lock(&opts->lock);
3383 mutex_unlock(&opts->lock);
3387 ret = kstrtobool(page, &stall);
3389 opts->common->can_stall = stall;
3393 mutex_unlock(&opts->lock);
3398 CONFIGFS_ATTR(fsg_opts_, stall);
3400 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
3401 static ssize_t fsg_opts_num_buffers_show(struct config_item *item, char *page)
3403 struct fsg_opts *opts = to_fsg_opts(item);
3406 mutex_lock(&opts->lock);
3407 result = sprintf(page, "%d", opts->common->fsg_num_buffers);
3408 mutex_unlock(&opts->lock);
3413 static ssize_t fsg_opts_num_buffers_store(struct config_item *item,
3414 const char *page, size_t len)
3416 struct fsg_opts *opts = to_fsg_opts(item);
3420 mutex_lock(&opts->lock);
3425 ret = kstrtou8(page, 0, &num);
3429 ret = fsg_common_set_num_buffers(opts->common, num);
3435 mutex_unlock(&opts->lock);
3439 CONFIGFS_ATTR(fsg_opts_, num_buffers);
3442 static struct configfs_attribute *fsg_attrs[] = {
3443 &fsg_opts_attr_stall,
3444 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
3445 &fsg_opts_attr_num_buffers,
3450 static struct configfs_group_operations fsg_group_ops = {
3451 .make_group = fsg_lun_make,
3452 .drop_item = fsg_lun_drop,
3455 static const struct config_item_type fsg_func_type = {
3456 .ct_item_ops = &fsg_item_ops,
3457 .ct_group_ops = &fsg_group_ops,
3458 .ct_attrs = fsg_attrs,
3459 .ct_owner = THIS_MODULE,
3462 static void fsg_free_inst(struct usb_function_instance *fi)
3464 struct fsg_opts *opts;
3466 opts = fsg_opts_from_func_inst(fi);
3467 fsg_common_release(opts->common);
3471 static struct usb_function_instance *fsg_alloc_inst(void)
3473 struct fsg_opts *opts;
3474 struct fsg_lun_config config;
3477 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
3479 return ERR_PTR(-ENOMEM);
3480 mutex_init(&opts->lock);
3481 opts->func_inst.free_func_inst = fsg_free_inst;
3482 opts->common = fsg_common_setup(opts->common);
3483 if (IS_ERR(opts->common)) {
3484 rc = PTR_ERR(opts->common);
3488 rc = fsg_common_set_num_buffers(opts->common,
3489 CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS);
3491 goto release_common;
3493 pr_info(FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
3495 memset(&config, 0, sizeof(config));
3496 config.removable = true;
3497 rc = fsg_common_create_lun(opts->common, &config, 0, "lun.0",
3498 (const char **)&opts->func_inst.group.cg_item.ci_name);
3500 goto release_buffers;
3502 opts->lun0.lun = opts->common->luns[0];
3503 opts->lun0.lun_id = 0;
3505 config_group_init_type_name(&opts->func_inst.group, "", &fsg_func_type);
3507 config_group_init_type_name(&opts->lun0.group, "lun.0", &fsg_lun_type);
3508 configfs_add_default_group(&opts->lun0.group, &opts->func_inst.group);
3510 return &opts->func_inst;
3513 fsg_common_free_buffers(opts->common);
3515 kfree(opts->common);
3521 static void fsg_free(struct usb_function *f)
3523 struct fsg_dev *fsg;
3524 struct fsg_opts *opts;
3526 fsg = container_of(f, struct fsg_dev, function);
3527 opts = container_of(f->fi, struct fsg_opts, func_inst);
3529 mutex_lock(&opts->lock);
3531 mutex_unlock(&opts->lock);
3536 static struct usb_function *fsg_alloc(struct usb_function_instance *fi)
3538 struct fsg_opts *opts = fsg_opts_from_func_inst(fi);
3539 struct fsg_common *common = opts->common;
3540 struct fsg_dev *fsg;
3542 fsg = kzalloc(sizeof(*fsg), GFP_KERNEL);
3544 return ERR_PTR(-ENOMEM);
3546 mutex_lock(&opts->lock);
3548 mutex_unlock(&opts->lock);
3550 fsg->function.name = FSG_DRIVER_DESC;
3551 fsg->function.bind = fsg_bind;
3552 fsg->function.unbind = fsg_unbind;
3553 fsg->function.setup = fsg_setup;
3554 fsg->function.set_alt = fsg_set_alt;
3555 fsg->function.disable = fsg_disable;
3556 fsg->function.free_func = fsg_free;
3558 fsg->common = common;
3560 return &fsg->function;
3563 DECLARE_USB_FUNCTION_INIT(mass_storage, fsg_alloc_inst, fsg_alloc);
3564 MODULE_LICENSE("GPL");
3565 MODULE_AUTHOR("Michal Nazarewicz");
3567 /************************* Module parameters *************************/
3570 void fsg_config_from_params(struct fsg_config *cfg,
3571 const struct fsg_module_parameters *params,
3572 unsigned int fsg_num_buffers)
3574 struct fsg_lun_config *lun;
3577 /* Configure LUNs */
3579 min(params->luns ?: (params->file_count ?: 1u),
3580 (unsigned)FSG_MAX_LUNS);
3581 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3582 lun->ro = !!params->ro[i];
3583 lun->cdrom = !!params->cdrom[i];
3584 lun->removable = !!params->removable[i];
3586 params->file_count > i && params->file[i][0]
3591 /* Let MSF use defaults */
3592 cfg->vendor_name = NULL;
3593 cfg->product_name = NULL;
3596 cfg->private_data = NULL;
3599 cfg->can_stall = params->stall;
3600 cfg->fsg_num_buffers = fsg_num_buffers;
3602 EXPORT_SYMBOL_GPL(fsg_config_from_params);