2 * f_mass_storage.c -- Mass Storage USB Composite Function
4 * Copyright (C) 2003-2008 Alan Stern
5 * Copyright (C) 2009 Samsung Electronics
6 * Author: Michal Nazarewicz <m.nazarewicz@samsung.com>
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions, and the following disclaimer,
14 * without modification.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. The names of the above-listed copyright holders may not be used
19 * to endorse or promote products derived from this software without
20 * specific prior written permission.
22 * ALTERNATIVELY, this software may be distributed under the terms of the
23 * GNU General Public License ("GPL") as published by the Free Software
24 * Foundation, either version 2 of that License or (at your option) any
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
28 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
29 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
31 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
32 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
33 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
34 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
35 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
36 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
37 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
42 * The Mass Storage Function acts as a USB Mass Storage device,
43 * appearing to the host as a disk drive or as a CD-ROM drive. In
44 * addition to providing an example of a genuinely useful composite
45 * function for a USB device, it also illustrates a technique of
46 * double-buffering for increased throughput.
48 * Function supports multiple logical units (LUNs). Backing storage
49 * for each LUN is provided by a regular file or a block device.
50 * Access for each LUN can be limited to read-only. Moreover, the
51 * function can indicate that LUN is removable and/or CD-ROM. (The
52 * later implies read-only access.)
54 * MSF is configured by specifying a fsg_config structure. It has the
57 * nluns Number of LUNs function have (anywhere from 1
58 * to FSG_MAX_LUNS which is 8).
59 * luns An array of LUN configuration values. This
60 * should be filled for each LUN that
61 * function will include (ie. for "nluns"
62 * LUNs). Each element of the array has
63 * the following fields:
64 * ->filename The path to the backing file for the LUN.
65 * Required if LUN is not marked as
67 * ->ro Flag specifying access to the LUN shall be
68 * read-only. This is implied if CD-ROM
69 * emulation is enabled as well as when
70 * it was impossible to open "filename"
72 * ->removable Flag specifying that LUN shall be indicated as
74 * ->cdrom Flag specifying that LUN shall be reported as
76 * ->nofua Flag specifying that FUA flag in SCSI WRITE(10,12)
77 * commands for this LUN shall be ignored.
79 * lun_name_format A printf-like format for names of the LUN
80 * devices. This determines how the
81 * directory in sysfs will be named.
82 * Unless you are using several MSFs in
83 * a single gadget (as opposed to single
84 * MSF in many configurations) you may
85 * leave it as NULL (in which case
86 * "lun%d" will be used). In the format
87 * you can use "%d" to index LUNs for
88 * MSF's with more than one LUN. (Beware
89 * that there is only one integer given
90 * as an argument for the format and
91 * specifying invalid format may cause
92 * unspecified behaviour.)
93 * thread_name Name of the kernel thread process used by the
94 * MSF. You can safely set it to NULL
95 * (in which case default "file-storage"
100 * release Information used as a reply to INQUIRY
101 * request. To use default set to NULL,
102 * NULL, 0xffff respectively. The first
103 * field should be 8 and the second 16
104 * characters or less.
106 * can_stall Set to permit function to halt bulk endpoints.
107 * Disabled on some USB devices known not
108 * to work correctly. You should set it
111 * If "removable" is not set for a LUN then a backing file must be
112 * specified. If it is set, then NULL filename means the LUN's medium
113 * is not loaded (an empty string as "filename" in the fsg_config
114 * structure causes error). The CD-ROM emulation includes a single
115 * data track and no audio tracks; hence there need be only one
116 * backing file per LUN. Note also that the CD-ROM block length is
117 * set to 512 rather than the more common value 2048.
120 * MSF includes support for module parameters. If gadget using it
121 * decides to use it, the following module parameters will be
124 * file=filename[,filename...]
125 * Names of the files or block devices used for
127 * ro=b[,b...] Default false, boolean for read-only access.
129 * Default true, boolean for removable media.
130 * cdrom=b[,b...] Default false, boolean for whether to emulate
132 * nofua=b[,b...] Default false, booleans for ignore FUA flag
133 * in SCSI WRITE(10,12) commands
134 * luns=N Default N = number of filenames, number of
136 * stall Default determined according to the type of
137 * USB device controller (usually true),
138 * boolean to permit the driver to halt
141 * The module parameters may be prefixed with some string. You need
142 * to consult gadget's documentation or source to verify whether it is
143 * using those module parameters and if it does what are the prefixes
144 * (look for FSG_MODULE_PARAMETERS() macro usage, what's inside it is
148 * Requirements are modest; only a bulk-in and a bulk-out endpoint are
149 * needed. The memory requirement amounts to two 16K buffers, size
150 * configurable by a parameter. Support is included for both
151 * full-speed and high-speed operation.
153 * Note that the driver is slightly non-portable in that it assumes a
154 * single memory/DMA buffer will be useable for bulk-in, bulk-out, and
155 * interrupt-in endpoints. With most device controllers this isn't an
156 * issue, but there may be some with hardware restrictions that prevent
157 * a buffer from being used by more than one endpoint.
160 * The pathnames of the backing files and the ro settings are
161 * available in the attribute files "file" and "ro" in the lun<n> (or
162 * to be more precise in a directory which name comes from
163 * "lun_name_format" option!) subdirectory of the gadget's sysfs
164 * directory. If the "removable" option is set, writing to these
165 * files will simulate ejecting/loading the medium (writing an empty
166 * line means eject) and adjusting a write-enable tab. Changes to the
167 * ro setting are not allowed when the medium is loaded or if CD-ROM
168 * emulation is being used.
170 * When a LUN receive an "eject" SCSI request (Start/Stop Unit),
171 * if the LUN is removable, the backing file is released to simulate
175 * This function is heavily based on "File-backed Storage Gadget" by
176 * Alan Stern which in turn is heavily based on "Gadget Zero" by David
177 * Brownell. The driver's SCSI command interface was based on the
178 * "Information technology - Small Computer System Interface - 2"
179 * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
180 * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
181 * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
182 * was based on the "Universal Serial Bus Mass Storage Class UFI
183 * Command Specification" document, Revision 1.0, December 14, 1998,
185 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
192 * The MSF is fairly straightforward. There is a main kernel
193 * thread that handles most of the work. Interrupt routines field
194 * callbacks from the controller driver: bulk- and interrupt-request
195 * completion notifications, endpoint-0 events, and disconnect events.
196 * Completion events are passed to the main thread by wakeup calls. Many
197 * ep0 requests are handled at interrupt time, but SetInterface,
198 * SetConfiguration, and device reset requests are forwarded to the
199 * thread in the form of "exceptions" using SIGUSR1 signals (since they
200 * should interrupt any ongoing file I/O operations).
202 * The thread's main routine implements the standard command/data/status
203 * parts of a SCSI interaction. It and its subroutines are full of tests
204 * for pending signals/exceptions -- all this polling is necessary since
205 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
206 * indication that the driver really wants to be running in userspace.)
207 * An important point is that so long as the thread is alive it keeps an
208 * open reference to the backing file. This will prevent unmounting
209 * the backing file's underlying filesystem and could cause problems
210 * during system shutdown, for example. To prevent such problems, the
211 * thread catches INT, TERM, and KILL signals and converts them into
214 * In normal operation the main thread is started during the gadget's
215 * fsg_bind() callback and stopped during fsg_unbind(). But it can
216 * also exit when it receives a signal, and there's no point leaving
217 * the gadget running when the thread is dead. At of this moment, MSF
218 * provides no way to deregister the gadget when thread dies -- maybe
219 * a callback functions is needed.
221 * To provide maximum throughput, the driver uses a circular pipeline of
222 * buffer heads (struct fsg_buffhd). In principle the pipeline can be
223 * arbitrarily long; in practice the benefits don't justify having more
224 * than 2 stages (i.e., double buffering). But it helps to think of the
225 * pipeline as being a long one. Each buffer head contains a bulk-in and
226 * a bulk-out request pointer (since the buffer can be used for both
227 * output and input -- directions always are given from the host's
228 * point of view) as well as a pointer to the buffer and various state
231 * Use of the pipeline follows a simple protocol. There is a variable
232 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
233 * At any time that buffer head may still be in use from an earlier
234 * request, so each buffer head has a state variable indicating whether
235 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
236 * buffer head to be EMPTY, filling the buffer either by file I/O or by
237 * USB I/O (during which the buffer head is BUSY), and marking the buffer
238 * head FULL when the I/O is complete. Then the buffer will be emptied
239 * (again possibly by USB I/O, during which it is marked BUSY) and
240 * finally marked EMPTY again (possibly by a completion routine).
242 * A module parameter tells the driver to avoid stalling the bulk
243 * endpoints wherever the transport specification allows. This is
244 * necessary for some UDCs like the SuperH, which cannot reliably clear a
245 * halt on a bulk endpoint. However, under certain circumstances the
246 * Bulk-only specification requires a stall. In such cases the driver
247 * will halt the endpoint and set a flag indicating that it should clear
248 * the halt in software during the next device reset. Hopefully this
249 * will permit everything to work correctly. Furthermore, although the
250 * specification allows the bulk-out endpoint to halt when the host sends
251 * too much data, implementing this would cause an unavoidable race.
252 * The driver will always use the "no-stall" approach for OUT transfers.
254 * One subtle point concerns sending status-stage responses for ep0
255 * requests. Some of these requests, such as device reset, can involve
256 * interrupting an ongoing file I/O operation, which might take an
257 * arbitrarily long time. During that delay the host might give up on
258 * the original ep0 request and issue a new one. When that happens the
259 * driver should not notify the host about completion of the original
260 * request, as the host will no longer be waiting for it. So the driver
261 * assigns to each ep0 request a unique tag, and it keeps track of the
262 * tag value of the request associated with a long-running exception
263 * (device-reset, interface-change, or configuration-change). When the
264 * exception handler is finished, the status-stage response is submitted
265 * only if the current ep0 request tag is equal to the exception request
266 * tag. Thus only the most recently received ep0 request will get a
267 * status-stage response.
269 * Warning: This driver source file is too long. It ought to be split up
270 * into a header file plus about 3 separate .c files, to handle the details
271 * of the Gadget, USB Mass Storage, and SCSI protocols.
275 /* #define VERBOSE_DEBUG */
276 /* #define DUMP_MSGS */
279 #include <linux/blkdev.h>
280 #include <linux/completion.h>
281 #include <linux/dcache.h>
282 #include <linux/delay.h>
283 #include <linux/device.h>
284 #include <linux/fcntl.h>
285 #include <linux/file.h>
286 #include <linux/fs.h>
287 #include <linux/kref.h>
288 #include <linux/kthread.h>
289 #include <linux/limits.h>
290 #include <linux/rwsem.h>
291 #include <linux/slab.h>
292 #include <linux/spinlock.h>
293 #include <linux/string.h>
294 #include <linux/freezer.h>
295 #include <linux/utsname.h>
297 #include <linux/usb/ch9.h>
298 #include <linux/usb/gadget.h>
300 #include "gadget_chips.h"
304 /*------------------------------------------------------------------------*/
306 #define FSG_DRIVER_DESC "Mass Storage Function"
307 #define FSG_DRIVER_VERSION "2009/09/11"
309 static const char fsg_string_interface[] = "Mass Storage";
312 #define FSG_NO_INTR_EP 1
313 #define FSG_NO_DEVICE_STRINGS 1
315 #define FSG_NO_INTR_EP 1
317 #include "storage_common.c"
320 /*-------------------------------------------------------------------------*/
325 /* FSF callback functions */
326 struct fsg_operations {
327 /* Callback function to call when thread exits. If no
328 * callback is set or it returns value lower then zero MSF
329 * will force eject all LUNs it operates on (including those
330 * marked as non-removable or with prevent_medium_removal flag
332 int (*thread_exits)(struct fsg_common *common);
334 /* Called prior to ejection. Negative return means error,
335 * zero means to continue with ejection, positive means not to
337 int (*pre_eject)(struct fsg_common *common,
338 struct fsg_lun *lun, int num);
339 /* Called after ejection. Negative return means error, zero
340 * or positive is just a success. */
341 int (*post_eject)(struct fsg_common *common,
342 struct fsg_lun *lun, int num);
346 /* Data shared by all the FSG instances. */
348 struct usb_gadget *gadget;
349 struct fsg_dev *fsg, *new_fsg;
350 wait_queue_head_t fsg_wait;
352 /* filesem protects: backing files in use */
353 struct rw_semaphore filesem;
355 /* lock protects: state, all the req_busy's */
358 struct usb_ep *ep0; /* Copy of gadget->ep0 */
359 struct usb_request *ep0req; /* Copy of cdev->req */
360 unsigned int ep0_req_tag;
362 struct fsg_buffhd *next_buffhd_to_fill;
363 struct fsg_buffhd *next_buffhd_to_drain;
364 struct fsg_buffhd buffhds[FSG_NUM_BUFFERS];
367 u8 cmnd[MAX_COMMAND_SIZE];
371 struct fsg_lun *luns;
372 struct fsg_lun *curlun;
374 unsigned int bulk_out_maxpacket;
375 enum fsg_state state; /* For exception handling */
376 unsigned int exception_req_tag;
378 enum data_direction data_dir;
380 u32 data_size_from_cmnd;
385 unsigned int can_stall:1;
386 unsigned int free_storage_on_release:1;
387 unsigned int phase_error:1;
388 unsigned int short_packet_received:1;
389 unsigned int bad_lun_okay:1;
390 unsigned int running:1;
392 int thread_wakeup_needed;
393 struct completion thread_notifier;
394 struct task_struct *thread_task;
396 /* Callback functions. */
397 const struct fsg_operations *ops;
398 /* Gadget's private data. */
401 /* Vendor (8 chars), product (16 chars), release (4
402 * hexadecimal digits) and NUL byte */
403 char inquiry_string[8 + 16 + 4 + 1];
411 struct fsg_lun_config {
412 const char *filename;
417 } luns[FSG_MAX_LUNS];
419 const char *lun_name_format;
420 const char *thread_name;
422 /* Callback functions. */
423 const struct fsg_operations *ops;
424 /* Gadget's private data. */
427 const char *vendor_name; /* 8 characters or less */
428 const char *product_name; /* 16 characters or less */
436 struct usb_function function;
437 struct usb_gadget *gadget; /* Copy of cdev->gadget */
438 struct fsg_common *common;
440 u16 interface_number;
442 unsigned int bulk_in_enabled:1;
443 unsigned int bulk_out_enabled:1;
445 unsigned long atomic_bitflags;
446 #define IGNORE_BULK_OUT 0
448 struct usb_ep *bulk_in;
449 struct usb_ep *bulk_out;
453 static inline int __fsg_is_set(struct fsg_common *common,
454 const char *func, unsigned line)
458 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
463 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
466 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
468 return container_of(f, struct fsg_dev, function);
472 typedef void (*fsg_routine_t)(struct fsg_dev *);
474 static int exception_in_progress(struct fsg_common *common)
476 return common->state > FSG_STATE_IDLE;
479 /* Make bulk-out requests be divisible by the maxpacket size */
480 static void set_bulk_out_req_length(struct fsg_common *common,
481 struct fsg_buffhd *bh, unsigned int length)
485 bh->bulk_out_intended_length = length;
486 rem = length % common->bulk_out_maxpacket;
488 length += common->bulk_out_maxpacket - rem;
489 bh->outreq->length = length;
492 /*-------------------------------------------------------------------------*/
494 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
498 if (ep == fsg->bulk_in)
500 else if (ep == fsg->bulk_out)
504 DBG(fsg, "%s set halt\n", name);
505 return usb_ep_set_halt(ep);
509 /*-------------------------------------------------------------------------*/
511 /* These routines may be called in process context or in_irq */
513 /* Caller must hold fsg->lock */
514 static void wakeup_thread(struct fsg_common *common)
516 /* Tell the main thread that something has happened */
517 common->thread_wakeup_needed = 1;
518 if (common->thread_task)
519 wake_up_process(common->thread_task);
523 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
527 /* Do nothing if a higher-priority exception is already in progress.
528 * If a lower-or-equal priority exception is in progress, preempt it
529 * and notify the main thread by sending it a signal. */
530 spin_lock_irqsave(&common->lock, flags);
531 if (common->state <= new_state) {
532 common->exception_req_tag = common->ep0_req_tag;
533 common->state = new_state;
534 if (common->thread_task)
535 send_sig_info(SIGUSR1, SEND_SIG_FORCED,
536 common->thread_task);
538 spin_unlock_irqrestore(&common->lock, flags);
542 /*-------------------------------------------------------------------------*/
544 static int ep0_queue(struct fsg_common *common)
548 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
549 common->ep0->driver_data = common;
550 if (rc != 0 && rc != -ESHUTDOWN) {
551 /* We can't do much more than wait for a reset */
552 WARNING(common, "error in submission: %s --> %d\n",
553 common->ep0->name, rc);
558 /*-------------------------------------------------------------------------*/
560 /* Bulk and interrupt endpoint completion handlers.
561 * These always run in_irq. */
563 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
565 struct fsg_common *common = ep->driver_data;
566 struct fsg_buffhd *bh = req->context;
568 if (req->status || req->actual != req->length)
569 DBG(common, "%s --> %d, %u/%u\n", __func__,
570 req->status, req->actual, req->length);
571 if (req->status == -ECONNRESET) /* Request was cancelled */
572 usb_ep_fifo_flush(ep);
574 /* Hold the lock while we update the request and buffer states */
576 spin_lock(&common->lock);
578 bh->state = BUF_STATE_EMPTY;
579 wakeup_thread(common);
580 spin_unlock(&common->lock);
583 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
585 struct fsg_common *common = ep->driver_data;
586 struct fsg_buffhd *bh = req->context;
588 dump_msg(common, "bulk-out", req->buf, req->actual);
589 if (req->status || req->actual != bh->bulk_out_intended_length)
590 DBG(common, "%s --> %d, %u/%u\n", __func__,
591 req->status, req->actual,
592 bh->bulk_out_intended_length);
593 if (req->status == -ECONNRESET) /* Request was cancelled */
594 usb_ep_fifo_flush(ep);
596 /* Hold the lock while we update the request and buffer states */
598 spin_lock(&common->lock);
600 bh->state = BUF_STATE_FULL;
601 wakeup_thread(common);
602 spin_unlock(&common->lock);
606 /*-------------------------------------------------------------------------*/
608 /* Ep0 class-specific handlers. These always run in_irq. */
610 static int fsg_setup(struct usb_function *f,
611 const struct usb_ctrlrequest *ctrl)
613 struct fsg_dev *fsg = fsg_from_func(f);
614 struct usb_request *req = fsg->common->ep0req;
615 u16 w_index = le16_to_cpu(ctrl->wIndex);
616 u16 w_value = le16_to_cpu(ctrl->wValue);
617 u16 w_length = le16_to_cpu(ctrl->wLength);
619 if (!fsg_is_set(fsg->common))
622 switch (ctrl->bRequest) {
624 case USB_BULK_RESET_REQUEST:
625 if (ctrl->bRequestType !=
626 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
628 if (w_index != fsg->interface_number || w_value != 0)
631 /* Raise an exception to stop the current operation
632 * and reinitialize our state. */
633 DBG(fsg, "bulk reset request\n");
634 raise_exception(fsg->common, FSG_STATE_RESET);
635 return DELAYED_STATUS;
637 case USB_BULK_GET_MAX_LUN_REQUEST:
638 if (ctrl->bRequestType !=
639 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
641 if (w_index != fsg->interface_number || w_value != 0)
643 VDBG(fsg, "get max LUN\n");
644 *(u8 *) req->buf = fsg->common->nluns - 1;
646 /* Respond with data/status */
647 req->length = min((u16)1, w_length);
648 return ep0_queue(fsg->common);
652 "unknown class-specific control req "
653 "%02x.%02x v%04x i%04x l%u\n",
654 ctrl->bRequestType, ctrl->bRequest,
655 le16_to_cpu(ctrl->wValue), w_index, w_length);
660 /*-------------------------------------------------------------------------*/
662 /* All the following routines run in process context */
665 /* Use this for bulk or interrupt transfers, not ep0 */
666 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
667 struct usb_request *req, int *pbusy,
668 enum fsg_buffer_state *state)
672 if (ep == fsg->bulk_in)
673 dump_msg(fsg, "bulk-in", req->buf, req->length);
675 spin_lock_irq(&fsg->common->lock);
677 *state = BUF_STATE_BUSY;
678 spin_unlock_irq(&fsg->common->lock);
679 rc = usb_ep_queue(ep, req, GFP_KERNEL);
682 *state = BUF_STATE_EMPTY;
684 /* We can't do much more than wait for a reset */
686 /* Note: currently the net2280 driver fails zero-length
687 * submissions if DMA is enabled. */
688 if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP &&
690 WARNING(fsg, "error in submission: %s --> %d\n",
695 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
697 if (!fsg_is_set(common))
699 start_transfer(common->fsg, common->fsg->bulk_in,
700 bh->inreq, &bh->inreq_busy, &bh->state);
704 static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
706 if (!fsg_is_set(common))
708 start_transfer(common->fsg, common->fsg->bulk_out,
709 bh->outreq, &bh->outreq_busy, &bh->state);
713 static int sleep_thread(struct fsg_common *common)
717 /* Wait until a signal arrives or we are woken up */
720 set_current_state(TASK_INTERRUPTIBLE);
721 if (signal_pending(current)) {
725 if (common->thread_wakeup_needed)
729 __set_current_state(TASK_RUNNING);
730 common->thread_wakeup_needed = 0;
735 /*-------------------------------------------------------------------------*/
737 static int do_read(struct fsg_common *common)
739 struct fsg_lun *curlun = common->curlun;
741 struct fsg_buffhd *bh;
744 loff_t file_offset, file_offset_tmp;
746 unsigned int partial_page;
749 /* Get the starting Logical Block Address and check that it's
751 if (common->cmnd[0] == READ_6)
752 lba = get_unaligned_be24(&common->cmnd[1]);
754 lba = get_unaligned_be32(&common->cmnd[2]);
756 /* We allow DPO (Disable Page Out = don't save data in the
757 * cache) and FUA (Force Unit Access = don't read from the
758 * cache), but we don't implement them. */
759 if ((common->cmnd[1] & ~0x18) != 0) {
760 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
764 if (lba >= curlun->num_sectors) {
765 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
768 file_offset = ((loff_t) lba) << 9;
770 /* Carry out the file reads */
771 amount_left = common->data_size_from_cmnd;
772 if (unlikely(amount_left == 0))
773 return -EIO; /* No default reply */
777 /* Figure out how much we need to read:
778 * Try to read the remaining amount.
779 * But don't read more than the buffer size.
780 * And don't try to read past the end of the file.
781 * Finally, if we're not at a page boundary, don't read past
783 * If this means reading 0 then we were asked to read past
784 * the end of file. */
785 amount = min(amount_left, FSG_BUFLEN);
786 amount = min((loff_t) amount,
787 curlun->file_length - file_offset);
788 partial_page = file_offset & (PAGE_CACHE_SIZE - 1);
789 if (partial_page > 0)
790 amount = min(amount, (unsigned int) PAGE_CACHE_SIZE -
793 /* Wait for the next buffer to become available */
794 bh = common->next_buffhd_to_fill;
795 while (bh->state != BUF_STATE_EMPTY) {
796 rc = sleep_thread(common);
801 /* If we were asked to read past the end of file,
802 * end with an empty buffer. */
805 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
806 curlun->sense_data_info = file_offset >> 9;
807 curlun->info_valid = 1;
808 bh->inreq->length = 0;
809 bh->state = BUF_STATE_FULL;
813 /* Perform the read */
814 file_offset_tmp = file_offset;
815 nread = vfs_read(curlun->filp,
816 (char __user *) bh->buf,
817 amount, &file_offset_tmp);
818 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
819 (unsigned long long) file_offset,
821 if (signal_pending(current))
825 LDBG(curlun, "error in file read: %d\n",
828 } else if (nread < amount) {
829 LDBG(curlun, "partial file read: %d/%u\n",
830 (int) nread, amount);
831 nread -= (nread & 511); /* Round down to a block */
833 file_offset += nread;
834 amount_left -= nread;
835 common->residue -= nread;
836 bh->inreq->length = nread;
837 bh->state = BUF_STATE_FULL;
839 /* If an error occurred, report it and its position */
840 if (nread < amount) {
841 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
842 curlun->sense_data_info = file_offset >> 9;
843 curlun->info_valid = 1;
847 if (amount_left == 0)
848 break; /* No more left to read */
850 /* Send this buffer and go read some more */
852 if (!start_in_transfer(common, bh))
853 /* Don't know what to do if common->fsg is NULL */
855 common->next_buffhd_to_fill = bh->next;
858 return -EIO; /* No default reply */
862 /*-------------------------------------------------------------------------*/
864 static int do_write(struct fsg_common *common)
866 struct fsg_lun *curlun = common->curlun;
868 struct fsg_buffhd *bh;
870 u32 amount_left_to_req, amount_left_to_write;
871 loff_t usb_offset, file_offset, file_offset_tmp;
873 unsigned int partial_page;
878 curlun->sense_data = SS_WRITE_PROTECTED;
881 spin_lock(&curlun->filp->f_lock);
882 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
883 spin_unlock(&curlun->filp->f_lock);
885 /* Get the starting Logical Block Address and check that it's
887 if (common->cmnd[0] == WRITE_6)
888 lba = get_unaligned_be24(&common->cmnd[1]);
890 lba = get_unaligned_be32(&common->cmnd[2]);
892 /* We allow DPO (Disable Page Out = don't save data in the
893 * cache) and FUA (Force Unit Access = write directly to the
894 * medium). We don't implement DPO; we implement FUA by
895 * performing synchronous output. */
896 if (common->cmnd[1] & ~0x18) {
897 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
900 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
901 spin_lock(&curlun->filp->f_lock);
902 curlun->filp->f_flags |= O_SYNC;
903 spin_unlock(&curlun->filp->f_lock);
906 if (lba >= curlun->num_sectors) {
907 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
911 /* Carry out the file writes */
913 file_offset = usb_offset = ((loff_t) lba) << 9;
914 amount_left_to_req = common->data_size_from_cmnd;
915 amount_left_to_write = common->data_size_from_cmnd;
917 while (amount_left_to_write > 0) {
919 /* Queue a request for more data from the host */
920 bh = common->next_buffhd_to_fill;
921 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
923 /* Figure out how much we want to get:
924 * Try to get the remaining amount.
925 * But don't get more than the buffer size.
926 * And don't try to go past the end of the file.
927 * If we're not at a page boundary,
928 * don't go past the next page.
929 * If this means getting 0, then we were asked
930 * to write past the end of file.
931 * Finally, round down to a block boundary. */
932 amount = min(amount_left_to_req, FSG_BUFLEN);
933 amount = min((loff_t) amount, curlun->file_length -
935 partial_page = usb_offset & (PAGE_CACHE_SIZE - 1);
936 if (partial_page > 0)
938 (unsigned int) PAGE_CACHE_SIZE - partial_page);
943 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
944 curlun->sense_data_info = usb_offset >> 9;
945 curlun->info_valid = 1;
948 amount -= (amount & 511);
951 /* Why were we were asked to transfer a
957 /* Get the next buffer */
958 usb_offset += amount;
959 common->usb_amount_left -= amount;
960 amount_left_to_req -= amount;
961 if (amount_left_to_req == 0)
964 /* amount is always divisible by 512, hence by
965 * the bulk-out maxpacket size */
966 bh->outreq->length = amount;
967 bh->bulk_out_intended_length = amount;
968 bh->outreq->short_not_ok = 1;
969 if (!start_out_transfer(common, bh))
970 /* Don't know what to do if
971 * common->fsg is NULL */
973 common->next_buffhd_to_fill = bh->next;
977 /* Write the received data to the backing file */
978 bh = common->next_buffhd_to_drain;
979 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
980 break; /* We stopped early */
981 if (bh->state == BUF_STATE_FULL) {
983 common->next_buffhd_to_drain = bh->next;
984 bh->state = BUF_STATE_EMPTY;
986 /* Did something go wrong with the transfer? */
987 if (bh->outreq->status != 0) {
988 curlun->sense_data = SS_COMMUNICATION_FAILURE;
989 curlun->sense_data_info = file_offset >> 9;
990 curlun->info_valid = 1;
994 amount = bh->outreq->actual;
995 if (curlun->file_length - file_offset < amount) {
997 "write %u @ %llu beyond end %llu\n",
998 amount, (unsigned long long) file_offset,
999 (unsigned long long) curlun->file_length);
1000 amount = curlun->file_length - file_offset;
1003 /* Perform the write */
1004 file_offset_tmp = file_offset;
1005 nwritten = vfs_write(curlun->filp,
1006 (char __user *) bh->buf,
1007 amount, &file_offset_tmp);
1008 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
1009 (unsigned long long) file_offset,
1011 if (signal_pending(current))
1012 return -EINTR; /* Interrupted! */
1015 LDBG(curlun, "error in file write: %d\n",
1018 } else if (nwritten < amount) {
1019 LDBG(curlun, "partial file write: %d/%u\n",
1020 (int) nwritten, amount);
1021 nwritten -= (nwritten & 511);
1022 /* Round down to a block */
1024 file_offset += nwritten;
1025 amount_left_to_write -= nwritten;
1026 common->residue -= nwritten;
1028 /* If an error occurred, report it and its position */
1029 if (nwritten < amount) {
1030 curlun->sense_data = SS_WRITE_ERROR;
1031 curlun->sense_data_info = file_offset >> 9;
1032 curlun->info_valid = 1;
1036 /* Did the host decide to stop early? */
1037 if (bh->outreq->actual != bh->outreq->length) {
1038 common->short_packet_received = 1;
1044 /* Wait for something to happen */
1045 rc = sleep_thread(common);
1050 return -EIO; /* No default reply */
1054 /*-------------------------------------------------------------------------*/
1056 static int do_synchronize_cache(struct fsg_common *common)
1058 struct fsg_lun *curlun = common->curlun;
1061 /* We ignore the requested LBA and write out all file's
1062 * dirty data buffers. */
1063 rc = fsg_lun_fsync_sub(curlun);
1065 curlun->sense_data = SS_WRITE_ERROR;
1070 /*-------------------------------------------------------------------------*/
1072 static void invalidate_sub(struct fsg_lun *curlun)
1074 struct file *filp = curlun->filp;
1075 struct inode *inode = filp->f_path.dentry->d_inode;
1078 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
1079 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
1082 static int do_verify(struct fsg_common *common)
1084 struct fsg_lun *curlun = common->curlun;
1086 u32 verification_length;
1087 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1088 loff_t file_offset, file_offset_tmp;
1090 unsigned int amount;
1093 /* Get the starting Logical Block Address and check that it's
1095 lba = get_unaligned_be32(&common->cmnd[2]);
1096 if (lba >= curlun->num_sectors) {
1097 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1101 /* We allow DPO (Disable Page Out = don't save data in the
1102 * cache) but we don't implement it. */
1103 if (common->cmnd[1] & ~0x10) {
1104 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1108 verification_length = get_unaligned_be16(&common->cmnd[7]);
1109 if (unlikely(verification_length == 0))
1110 return -EIO; /* No default reply */
1112 /* Prepare to carry out the file verify */
1113 amount_left = verification_length << 9;
1114 file_offset = ((loff_t) lba) << 9;
1116 /* Write out all the dirty buffers before invalidating them */
1117 fsg_lun_fsync_sub(curlun);
1118 if (signal_pending(current))
1121 invalidate_sub(curlun);
1122 if (signal_pending(current))
1125 /* Just try to read the requested blocks */
1126 while (amount_left > 0) {
1128 /* Figure out how much we need to read:
1129 * Try to read the remaining amount, but not more than
1131 * And don't try to read past the end of the file.
1132 * If this means reading 0 then we were asked to read
1133 * past the end of file. */
1134 amount = min(amount_left, FSG_BUFLEN);
1135 amount = min((loff_t) amount,
1136 curlun->file_length - file_offset);
1138 curlun->sense_data =
1139 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1140 curlun->sense_data_info = file_offset >> 9;
1141 curlun->info_valid = 1;
1145 /* Perform the read */
1146 file_offset_tmp = file_offset;
1147 nread = vfs_read(curlun->filp,
1148 (char __user *) bh->buf,
1149 amount, &file_offset_tmp);
1150 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1151 (unsigned long long) file_offset,
1153 if (signal_pending(current))
1157 LDBG(curlun, "error in file verify: %d\n",
1160 } else if (nread < amount) {
1161 LDBG(curlun, "partial file verify: %d/%u\n",
1162 (int) nread, amount);
1163 nread -= (nread & 511); /* Round down to a sector */
1166 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1167 curlun->sense_data_info = file_offset >> 9;
1168 curlun->info_valid = 1;
1171 file_offset += nread;
1172 amount_left -= nread;
1178 /*-------------------------------------------------------------------------*/
1180 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1182 struct fsg_lun *curlun = common->curlun;
1183 u8 *buf = (u8 *) bh->buf;
1185 if (!curlun) { /* Unsupported LUNs are okay */
1186 common->bad_lun_okay = 1;
1188 buf[0] = 0x7f; /* Unsupported, no device-type */
1189 buf[4] = 31; /* Additional length */
1193 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1194 buf[1] = curlun->removable ? 0x80 : 0;
1195 buf[2] = 2; /* ANSI SCSI level 2 */
1196 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1197 buf[4] = 31; /* Additional length */
1198 buf[5] = 0; /* No special options */
1201 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1206 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1208 struct fsg_lun *curlun = common->curlun;
1209 u8 *buf = (u8 *) bh->buf;
1214 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1216 * If a REQUEST SENSE command is received from an initiator
1217 * with a pending unit attention condition (before the target
1218 * generates the contingent allegiance condition), then the
1219 * target shall either:
1220 * a) report any pending sense data and preserve the unit
1221 * attention condition on the logical unit, or,
1222 * b) report the unit attention condition, may discard any
1223 * pending sense data, and clear the unit attention
1224 * condition on the logical unit for that initiator.
1226 * FSG normally uses option a); enable this code to use option b).
1229 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1230 curlun->sense_data = curlun->unit_attention_data;
1231 curlun->unit_attention_data = SS_NO_SENSE;
1235 if (!curlun) { /* Unsupported LUNs are okay */
1236 common->bad_lun_okay = 1;
1237 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1241 sd = curlun->sense_data;
1242 sdinfo = curlun->sense_data_info;
1243 valid = curlun->info_valid << 7;
1244 curlun->sense_data = SS_NO_SENSE;
1245 curlun->sense_data_info = 0;
1246 curlun->info_valid = 0;
1250 buf[0] = valid | 0x70; /* Valid, current error */
1252 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1253 buf[7] = 18 - 8; /* Additional sense length */
1260 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1262 struct fsg_lun *curlun = common->curlun;
1263 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1264 int pmi = common->cmnd[8];
1265 u8 *buf = (u8 *) bh->buf;
1267 /* Check the PMI and LBA fields */
1268 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1269 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1273 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1274 /* Max logical block */
1275 put_unaligned_be32(512, &buf[4]); /* Block length */
1280 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1282 struct fsg_lun *curlun = common->curlun;
1283 int msf = common->cmnd[1] & 0x02;
1284 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1285 u8 *buf = (u8 *) bh->buf;
1287 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1288 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1291 if (lba >= curlun->num_sectors) {
1292 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1297 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1298 store_cdrom_address(&buf[4], msf, lba);
1303 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1305 struct fsg_lun *curlun = common->curlun;
1306 int msf = common->cmnd[1] & 0x02;
1307 int start_track = common->cmnd[6];
1308 u8 *buf = (u8 *) bh->buf;
1310 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1312 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1317 buf[1] = (20-2); /* TOC data length */
1318 buf[2] = 1; /* First track number */
1319 buf[3] = 1; /* Last track number */
1320 buf[5] = 0x16; /* Data track, copying allowed */
1321 buf[6] = 0x01; /* Only track is number 1 */
1322 store_cdrom_address(&buf[8], msf, 0);
1324 buf[13] = 0x16; /* Lead-out track is data */
1325 buf[14] = 0xAA; /* Lead-out track number */
1326 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1331 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1333 struct fsg_lun *curlun = common->curlun;
1334 int mscmnd = common->cmnd[0];
1335 u8 *buf = (u8 *) bh->buf;
1338 int changeable_values, all_pages;
1342 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1343 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1346 pc = common->cmnd[2] >> 6;
1347 page_code = common->cmnd[2] & 0x3f;
1349 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1352 changeable_values = (pc == 1);
1353 all_pages = (page_code == 0x3f);
1355 /* Write the mode parameter header. Fixed values are: default
1356 * medium type, no cache control (DPOFUA), and no block descriptors.
1357 * The only variable value is the WriteProtect bit. We will fill in
1358 * the mode data length later. */
1360 if (mscmnd == MODE_SENSE) {
1361 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1364 } else { /* MODE_SENSE_10 */
1365 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1367 limit = 65535; /* Should really be FSG_BUFLEN */
1370 /* No block descriptors */
1372 /* The mode pages, in numerical order. The only page we support
1373 * is the Caching page. */
1374 if (page_code == 0x08 || all_pages) {
1376 buf[0] = 0x08; /* Page code */
1377 buf[1] = 10; /* Page length */
1378 memset(buf+2, 0, 10); /* None of the fields are changeable */
1380 if (!changeable_values) {
1381 buf[2] = 0x04; /* Write cache enable, */
1382 /* Read cache not disabled */
1383 /* No cache retention priorities */
1384 put_unaligned_be16(0xffff, &buf[4]);
1385 /* Don't disable prefetch */
1386 /* Minimum prefetch = 0 */
1387 put_unaligned_be16(0xffff, &buf[8]);
1388 /* Maximum prefetch */
1389 put_unaligned_be16(0xffff, &buf[10]);
1390 /* Maximum prefetch ceiling */
1395 /* Check that a valid page was requested and the mode data length
1396 * isn't too long. */
1398 if (!valid_page || len > limit) {
1399 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1403 /* Store the mode data length */
1404 if (mscmnd == MODE_SENSE)
1407 put_unaligned_be16(len - 2, buf0);
1412 static int do_start_stop(struct fsg_common *common)
1414 struct fsg_lun *curlun = common->curlun;
1419 } else if (!curlun->removable) {
1420 curlun->sense_data = SS_INVALID_COMMAND;
1422 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1423 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1424 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1428 loej = common->cmnd[4] & 0x02;
1429 start = common->cmnd[4] & 0x01;
1431 /* Our emulation doesn't support mounting; the medium is
1432 * available for use as soon as it is loaded. */
1434 if (!fsg_lun_is_open(curlun)) {
1435 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1441 /* Are we allowed to unload the media? */
1442 if (curlun->prevent_medium_removal) {
1443 LDBG(curlun, "unload attempt prevented\n");
1444 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1451 /* Simulate an unload/eject */
1452 if (common->ops && common->ops->pre_eject) {
1453 int r = common->ops->pre_eject(common, curlun,
1454 curlun - common->luns);
1455 if (unlikely(r < 0))
1461 up_read(&common->filesem);
1462 down_write(&common->filesem);
1463 fsg_lun_close(curlun);
1464 up_write(&common->filesem);
1465 down_read(&common->filesem);
1467 return common->ops && common->ops->post_eject
1468 ? min(0, common->ops->post_eject(common, curlun,
1469 curlun - common->luns))
1474 static int do_prevent_allow(struct fsg_common *common)
1476 struct fsg_lun *curlun = common->curlun;
1479 if (!common->curlun) {
1481 } else if (!common->curlun->removable) {
1482 common->curlun->sense_data = SS_INVALID_COMMAND;
1486 prevent = common->cmnd[4] & 0x01;
1487 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1488 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1492 if (curlun->prevent_medium_removal && !prevent)
1493 fsg_lun_fsync_sub(curlun);
1494 curlun->prevent_medium_removal = prevent;
1499 static int do_read_format_capacities(struct fsg_common *common,
1500 struct fsg_buffhd *bh)
1502 struct fsg_lun *curlun = common->curlun;
1503 u8 *buf = (u8 *) bh->buf;
1505 buf[0] = buf[1] = buf[2] = 0;
1506 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1509 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1510 /* Number of blocks */
1511 put_unaligned_be32(512, &buf[4]); /* Block length */
1512 buf[4] = 0x02; /* Current capacity */
1517 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1519 struct fsg_lun *curlun = common->curlun;
1521 /* We don't support MODE SELECT */
1523 curlun->sense_data = SS_INVALID_COMMAND;
1528 /*-------------------------------------------------------------------------*/
1530 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1534 rc = fsg_set_halt(fsg, fsg->bulk_in);
1536 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1538 if (rc != -EAGAIN) {
1539 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1544 /* Wait for a short time and then try again */
1545 if (msleep_interruptible(100) != 0)
1547 rc = usb_ep_set_halt(fsg->bulk_in);
1552 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1556 DBG(fsg, "bulk-in set wedge\n");
1557 rc = usb_ep_set_wedge(fsg->bulk_in);
1559 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1561 if (rc != -EAGAIN) {
1562 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1567 /* Wait for a short time and then try again */
1568 if (msleep_interruptible(100) != 0)
1570 rc = usb_ep_set_wedge(fsg->bulk_in);
1575 static int pad_with_zeros(struct fsg_dev *fsg)
1577 struct fsg_buffhd *bh = fsg->common->next_buffhd_to_fill;
1578 u32 nkeep = bh->inreq->length;
1582 bh->state = BUF_STATE_EMPTY; /* For the first iteration */
1583 fsg->common->usb_amount_left = nkeep + fsg->common->residue;
1584 while (fsg->common->usb_amount_left > 0) {
1586 /* Wait for the next buffer to be free */
1587 while (bh->state != BUF_STATE_EMPTY) {
1588 rc = sleep_thread(fsg->common);
1593 nsend = min(fsg->common->usb_amount_left, FSG_BUFLEN);
1594 memset(bh->buf + nkeep, 0, nsend - nkeep);
1595 bh->inreq->length = nsend;
1596 bh->inreq->zero = 0;
1597 start_transfer(fsg, fsg->bulk_in, bh->inreq,
1598 &bh->inreq_busy, &bh->state);
1599 bh = fsg->common->next_buffhd_to_fill = bh->next;
1600 fsg->common->usb_amount_left -= nsend;
1606 static int throw_away_data(struct fsg_common *common)
1608 struct fsg_buffhd *bh;
1612 for (bh = common->next_buffhd_to_drain;
1613 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1614 bh = common->next_buffhd_to_drain) {
1616 /* Throw away the data in a filled buffer */
1617 if (bh->state == BUF_STATE_FULL) {
1619 bh->state = BUF_STATE_EMPTY;
1620 common->next_buffhd_to_drain = bh->next;
1622 /* A short packet or an error ends everything */
1623 if (bh->outreq->actual != bh->outreq->length ||
1624 bh->outreq->status != 0) {
1625 raise_exception(common,
1626 FSG_STATE_ABORT_BULK_OUT);
1632 /* Try to submit another request if we need one */
1633 bh = common->next_buffhd_to_fill;
1634 if (bh->state == BUF_STATE_EMPTY
1635 && common->usb_amount_left > 0) {
1636 amount = min(common->usb_amount_left, FSG_BUFLEN);
1638 /* amount is always divisible by 512, hence by
1639 * the bulk-out maxpacket size */
1640 bh->outreq->length = amount;
1641 bh->bulk_out_intended_length = amount;
1642 bh->outreq->short_not_ok = 1;
1643 if (!start_out_transfer(common, bh))
1644 /* Don't know what to do if
1645 * common->fsg is NULL */
1647 common->next_buffhd_to_fill = bh->next;
1648 common->usb_amount_left -= amount;
1652 /* Otherwise wait for something to happen */
1653 rc = sleep_thread(common);
1661 static int finish_reply(struct fsg_common *common)
1663 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1666 switch (common->data_dir) {
1668 break; /* Nothing to send */
1670 /* If we don't know whether the host wants to read or write,
1671 * this must be CB or CBI with an unknown command. We mustn't
1672 * try to send or receive any data. So stall both bulk pipes
1673 * if we can and wait for a reset. */
1674 case DATA_DIR_UNKNOWN:
1675 if (!common->can_stall) {
1677 } else if (fsg_is_set(common)) {
1678 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1679 rc = halt_bulk_in_endpoint(common->fsg);
1681 /* Don't know what to do if common->fsg is NULL */
1686 /* All but the last buffer of data must have already been sent */
1687 case DATA_DIR_TO_HOST:
1688 if (common->data_size == 0) {
1689 /* Nothing to send */
1691 /* If there's no residue, simply send the last buffer */
1692 } else if (common->residue == 0) {
1693 bh->inreq->zero = 0;
1694 if (!start_in_transfer(common, bh))
1696 common->next_buffhd_to_fill = bh->next;
1698 /* For Bulk-only, if we're allowed to stall then send the
1699 * short packet and halt the bulk-in endpoint. If we can't
1700 * stall, pad out the remaining data with 0's. */
1701 } else if (common->can_stall) {
1702 bh->inreq->zero = 1;
1703 if (!start_in_transfer(common, bh))
1704 /* Don't know what to do if
1705 * common->fsg is NULL */
1707 common->next_buffhd_to_fill = bh->next;
1709 rc = halt_bulk_in_endpoint(common->fsg);
1710 } else if (fsg_is_set(common)) {
1711 rc = pad_with_zeros(common->fsg);
1713 /* Don't know what to do if common->fsg is NULL */
1718 /* We have processed all we want from the data the host has sent.
1719 * There may still be outstanding bulk-out requests. */
1720 case DATA_DIR_FROM_HOST:
1721 if (common->residue == 0) {
1722 /* Nothing to receive */
1724 /* Did the host stop sending unexpectedly early? */
1725 } else if (common->short_packet_received) {
1726 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1729 /* We haven't processed all the incoming data. Even though
1730 * we may be allowed to stall, doing so would cause a race.
1731 * The controller may already have ACK'ed all the remaining
1732 * bulk-out packets, in which case the host wouldn't see a
1733 * STALL. Not realizing the endpoint was halted, it wouldn't
1734 * clear the halt -- leading to problems later on. */
1736 } else if (common->can_stall) {
1737 if (fsg_is_set(common))
1738 fsg_set_halt(common->fsg,
1739 common->fsg->bulk_out);
1740 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1744 /* We can't stall. Read in the excess data and throw it
1747 rc = throw_away_data(common);
1755 static int send_status(struct fsg_common *common)
1757 struct fsg_lun *curlun = common->curlun;
1758 struct fsg_buffhd *bh;
1759 struct bulk_cs_wrap *csw;
1761 u8 status = USB_STATUS_PASS;
1764 /* Wait for the next buffer to become available */
1765 bh = common->next_buffhd_to_fill;
1766 while (bh->state != BUF_STATE_EMPTY) {
1767 rc = sleep_thread(common);
1773 sd = curlun->sense_data;
1774 sdinfo = curlun->sense_data_info;
1775 } else if (common->bad_lun_okay)
1778 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1780 if (common->phase_error) {
1781 DBG(common, "sending phase-error status\n");
1782 status = USB_STATUS_PHASE_ERROR;
1783 sd = SS_INVALID_COMMAND;
1784 } else if (sd != SS_NO_SENSE) {
1785 DBG(common, "sending command-failure status\n");
1786 status = USB_STATUS_FAIL;
1787 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1789 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1792 /* Store and send the Bulk-only CSW */
1793 csw = (void *)bh->buf;
1795 csw->Signature = cpu_to_le32(USB_BULK_CS_SIG);
1796 csw->Tag = common->tag;
1797 csw->Residue = cpu_to_le32(common->residue);
1798 csw->Status = status;
1800 bh->inreq->length = USB_BULK_CS_WRAP_LEN;
1801 bh->inreq->zero = 0;
1802 if (!start_in_transfer(common, bh))
1803 /* Don't know what to do if common->fsg is NULL */
1806 common->next_buffhd_to_fill = bh->next;
1811 /*-------------------------------------------------------------------------*/
1813 /* Check whether the command is properly formed and whether its data size
1814 * and direction agree with the values we already have. */
1815 static int check_command(struct fsg_common *common, int cmnd_size,
1816 enum data_direction data_dir, unsigned int mask,
1817 int needs_medium, const char *name)
1820 int lun = common->cmnd[1] >> 5;
1821 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1823 struct fsg_lun *curlun;
1826 if (common->data_dir != DATA_DIR_UNKNOWN)
1827 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1829 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1830 name, cmnd_size, dirletter[(int) data_dir],
1831 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1833 /* We can't reply at all until we know the correct data direction
1835 if (common->data_size_from_cmnd == 0)
1836 data_dir = DATA_DIR_NONE;
1837 if (common->data_size < common->data_size_from_cmnd) {
1838 /* Host data size < Device data size is a phase error.
1839 * Carry out the command, but only transfer as much as
1840 * we are allowed. */
1841 common->data_size_from_cmnd = common->data_size;
1842 common->phase_error = 1;
1844 common->residue = common->data_size;
1845 common->usb_amount_left = common->data_size;
1847 /* Conflicting data directions is a phase error */
1848 if (common->data_dir != data_dir
1849 && common->data_size_from_cmnd > 0) {
1850 common->phase_error = 1;
1854 /* Verify the length of the command itself */
1855 if (cmnd_size != common->cmnd_size) {
1857 /* Special case workaround: There are plenty of buggy SCSI
1858 * implementations. Many have issues with cbw->Length
1859 * field passing a wrong command size. For those cases we
1860 * always try to work around the problem by using the length
1861 * sent by the host side provided it is at least as large
1862 * as the correct command length.
1863 * Examples of such cases would be MS-Windows, which issues
1864 * REQUEST SENSE with cbw->Length == 12 where it should
1865 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1866 * REQUEST SENSE with cbw->Length == 10 where it should
1869 if (cmnd_size <= common->cmnd_size) {
1870 DBG(common, "%s is buggy! Expected length %d "
1871 "but we got %d\n", name,
1872 cmnd_size, common->cmnd_size);
1873 cmnd_size = common->cmnd_size;
1875 common->phase_error = 1;
1880 /* Check that the LUN values are consistent */
1881 if (common->lun != lun)
1882 DBG(common, "using LUN %d from CBW, not LUN %d from CDB\n",
1886 if (common->lun >= 0 && common->lun < common->nluns) {
1887 curlun = &common->luns[common->lun];
1888 common->curlun = curlun;
1889 if (common->cmnd[0] != REQUEST_SENSE) {
1890 curlun->sense_data = SS_NO_SENSE;
1891 curlun->sense_data_info = 0;
1892 curlun->info_valid = 0;
1895 common->curlun = NULL;
1897 common->bad_lun_okay = 0;
1899 /* INQUIRY and REQUEST SENSE commands are explicitly allowed
1900 * to use unsupported LUNs; all others may not. */
1901 if (common->cmnd[0] != INQUIRY &&
1902 common->cmnd[0] != REQUEST_SENSE) {
1903 DBG(common, "unsupported LUN %d\n", common->lun);
1908 /* If a unit attention condition exists, only INQUIRY and
1909 * REQUEST SENSE commands are allowed; anything else must fail. */
1910 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1911 common->cmnd[0] != INQUIRY &&
1912 common->cmnd[0] != REQUEST_SENSE) {
1913 curlun->sense_data = curlun->unit_attention_data;
1914 curlun->unit_attention_data = SS_NO_SENSE;
1918 /* Check that only command bytes listed in the mask are non-zero */
1919 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1920 for (i = 1; i < cmnd_size; ++i) {
1921 if (common->cmnd[i] && !(mask & (1 << i))) {
1923 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1928 /* If the medium isn't mounted and the command needs to access
1929 * it, return an error. */
1930 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1931 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1939 static int do_scsi_command(struct fsg_common *common)
1941 struct fsg_buffhd *bh;
1943 int reply = -EINVAL;
1945 static char unknown[16];
1949 /* Wait for the next buffer to become available for data or status */
1950 bh = common->next_buffhd_to_fill;
1951 common->next_buffhd_to_drain = bh;
1952 while (bh->state != BUF_STATE_EMPTY) {
1953 rc = sleep_thread(common);
1957 common->phase_error = 0;
1958 common->short_packet_received = 0;
1960 down_read(&common->filesem); /* We're using the backing file */
1961 switch (common->cmnd[0]) {
1964 common->data_size_from_cmnd = common->cmnd[4];
1965 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1969 reply = do_inquiry(common, bh);
1973 common->data_size_from_cmnd = common->cmnd[4];
1974 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1978 reply = do_mode_select(common, bh);
1981 case MODE_SELECT_10:
1982 common->data_size_from_cmnd =
1983 get_unaligned_be16(&common->cmnd[7]);
1984 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1988 reply = do_mode_select(common, bh);
1992 common->data_size_from_cmnd = common->cmnd[4];
1993 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1994 (1<<1) | (1<<2) | (1<<4), 0,
1997 reply = do_mode_sense(common, bh);
2001 common->data_size_from_cmnd =
2002 get_unaligned_be16(&common->cmnd[7]);
2003 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2004 (1<<1) | (1<<2) | (3<<7), 0,
2007 reply = do_mode_sense(common, bh);
2010 case ALLOW_MEDIUM_REMOVAL:
2011 common->data_size_from_cmnd = 0;
2012 reply = check_command(common, 6, DATA_DIR_NONE,
2014 "PREVENT-ALLOW MEDIUM REMOVAL");
2016 reply = do_prevent_allow(common);
2020 i = common->cmnd[4];
2021 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
2022 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2026 reply = do_read(common);
2030 common->data_size_from_cmnd =
2031 get_unaligned_be16(&common->cmnd[7]) << 9;
2032 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2033 (1<<1) | (0xf<<2) | (3<<7), 1,
2036 reply = do_read(common);
2040 common->data_size_from_cmnd =
2041 get_unaligned_be32(&common->cmnd[6]) << 9;
2042 reply = check_command(common, 12, DATA_DIR_TO_HOST,
2043 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2046 reply = do_read(common);
2050 common->data_size_from_cmnd = 8;
2051 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2052 (0xf<<2) | (1<<8), 1,
2055 reply = do_read_capacity(common, bh);
2059 if (!common->curlun || !common->curlun->cdrom)
2061 common->data_size_from_cmnd =
2062 get_unaligned_be16(&common->cmnd[7]);
2063 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2064 (3<<7) | (0x1f<<1), 1,
2067 reply = do_read_header(common, bh);
2071 if (!common->curlun || !common->curlun->cdrom)
2073 common->data_size_from_cmnd =
2074 get_unaligned_be16(&common->cmnd[7]);
2075 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2079 reply = do_read_toc(common, bh);
2082 case READ_FORMAT_CAPACITIES:
2083 common->data_size_from_cmnd =
2084 get_unaligned_be16(&common->cmnd[7]);
2085 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2087 "READ FORMAT CAPACITIES");
2089 reply = do_read_format_capacities(common, bh);
2093 common->data_size_from_cmnd = common->cmnd[4];
2094 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2098 reply = do_request_sense(common, bh);
2102 common->data_size_from_cmnd = 0;
2103 reply = check_command(common, 6, DATA_DIR_NONE,
2107 reply = do_start_stop(common);
2110 case SYNCHRONIZE_CACHE:
2111 common->data_size_from_cmnd = 0;
2112 reply = check_command(common, 10, DATA_DIR_NONE,
2113 (0xf<<2) | (3<<7), 1,
2114 "SYNCHRONIZE CACHE");
2116 reply = do_synchronize_cache(common);
2119 case TEST_UNIT_READY:
2120 common->data_size_from_cmnd = 0;
2121 reply = check_command(common, 6, DATA_DIR_NONE,
2126 /* Although optional, this command is used by MS-Windows. We
2127 * support a minimal version: BytChk must be 0. */
2129 common->data_size_from_cmnd = 0;
2130 reply = check_command(common, 10, DATA_DIR_NONE,
2131 (1<<1) | (0xf<<2) | (3<<7), 1,
2134 reply = do_verify(common);
2138 i = common->cmnd[4];
2139 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
2140 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
2144 reply = do_write(common);
2148 common->data_size_from_cmnd =
2149 get_unaligned_be16(&common->cmnd[7]) << 9;
2150 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
2151 (1<<1) | (0xf<<2) | (3<<7), 1,
2154 reply = do_write(common);
2158 common->data_size_from_cmnd =
2159 get_unaligned_be32(&common->cmnd[6]) << 9;
2160 reply = check_command(common, 12, DATA_DIR_FROM_HOST,
2161 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2164 reply = do_write(common);
2167 /* Some mandatory commands that we recognize but don't implement.
2168 * They don't mean much in this setting. It's left as an exercise
2169 * for anyone interested to implement RESERVE and RELEASE in terms
2170 * of Posix locks. */
2174 case SEND_DIAGNOSTIC:
2179 common->data_size_from_cmnd = 0;
2180 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2181 reply = check_command(common, common->cmnd_size,
2182 DATA_DIR_UNKNOWN, 0xff, 0, unknown);
2184 common->curlun->sense_data = SS_INVALID_COMMAND;
2189 up_read(&common->filesem);
2191 if (reply == -EINTR || signal_pending(current))
2194 /* Set up the single reply buffer for finish_reply() */
2195 if (reply == -EINVAL)
2196 reply = 0; /* Error reply length */
2197 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2198 reply = min((u32) reply, common->data_size_from_cmnd);
2199 bh->inreq->length = reply;
2200 bh->state = BUF_STATE_FULL;
2201 common->residue -= reply;
2202 } /* Otherwise it's already set */
2208 /*-------------------------------------------------------------------------*/
2210 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2212 struct usb_request *req = bh->outreq;
2213 struct fsg_bulk_cb_wrap *cbw = req->buf;
2214 struct fsg_common *common = fsg->common;
2216 /* Was this a real packet? Should it be ignored? */
2217 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2220 /* Is the CBW valid? */
2221 if (req->actual != USB_BULK_CB_WRAP_LEN ||
2222 cbw->Signature != cpu_to_le32(
2224 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2226 le32_to_cpu(cbw->Signature));
2228 /* The Bulk-only spec says we MUST stall the IN endpoint
2229 * (6.6.1), so it's unavoidable. It also says we must
2230 * retain this state until the next reset, but there's
2231 * no way to tell the controller driver it should ignore
2232 * Clear-Feature(HALT) requests.
2234 * We aren't required to halt the OUT endpoint; instead
2235 * we can simply accept and discard any data received
2236 * until the next reset. */
2237 wedge_bulk_in_endpoint(fsg);
2238 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2242 /* Is the CBW meaningful? */
2243 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG ||
2244 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2245 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2247 cbw->Lun, cbw->Flags, cbw->Length);
2249 /* We can do anything we want here, so let's stall the
2250 * bulk pipes if we are allowed to. */
2251 if (common->can_stall) {
2252 fsg_set_halt(fsg, fsg->bulk_out);
2253 halt_bulk_in_endpoint(fsg);
2258 /* Save the command for later */
2259 common->cmnd_size = cbw->Length;
2260 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2261 if (cbw->Flags & USB_BULK_IN_FLAG)
2262 common->data_dir = DATA_DIR_TO_HOST;
2264 common->data_dir = DATA_DIR_FROM_HOST;
2265 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2266 if (common->data_size == 0)
2267 common->data_dir = DATA_DIR_NONE;
2268 common->lun = cbw->Lun;
2269 common->tag = cbw->Tag;
2274 static int get_next_command(struct fsg_common *common)
2276 struct fsg_buffhd *bh;
2279 /* Wait for the next buffer to become available */
2280 bh = common->next_buffhd_to_fill;
2281 while (bh->state != BUF_STATE_EMPTY) {
2282 rc = sleep_thread(common);
2287 /* Queue a request to read a Bulk-only CBW */
2288 set_bulk_out_req_length(common, bh, USB_BULK_CB_WRAP_LEN);
2289 bh->outreq->short_not_ok = 1;
2290 if (!start_out_transfer(common, bh))
2291 /* Don't know what to do if common->fsg is NULL */
2294 /* We will drain the buffer in software, which means we
2295 * can reuse it for the next filling. No need to advance
2296 * next_buffhd_to_fill. */
2298 /* Wait for the CBW to arrive */
2299 while (bh->state != BUF_STATE_FULL) {
2300 rc = sleep_thread(common);
2305 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2306 bh->state = BUF_STATE_EMPTY;
2312 /*-------------------------------------------------------------------------*/
2314 static int enable_endpoint(struct fsg_common *common, struct usb_ep *ep,
2315 const struct usb_endpoint_descriptor *d)
2319 ep->driver_data = common;
2320 rc = usb_ep_enable(ep, d);
2322 ERROR(common, "can't enable %s, result %d\n", ep->name, rc);
2326 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2327 struct usb_request **preq)
2329 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2332 ERROR(common, "can't allocate request for %s\n", ep->name);
2336 /* Reset interface setting and re-init endpoint state (toggle etc). */
2337 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2339 const struct usb_endpoint_descriptor *d;
2340 struct fsg_dev *fsg;
2343 if (common->running)
2344 DBG(common, "reset interface\n");
2347 /* Deallocate the requests */
2351 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2352 struct fsg_buffhd *bh = &common->buffhds[i];
2355 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2359 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2364 /* Disable the endpoints */
2365 if (fsg->bulk_in_enabled) {
2366 usb_ep_disable(fsg->bulk_in);
2367 fsg->bulk_in_enabled = 0;
2369 if (fsg->bulk_out_enabled) {
2370 usb_ep_disable(fsg->bulk_out);
2371 fsg->bulk_out_enabled = 0;
2375 wake_up(&common->fsg_wait);
2378 common->running = 0;
2382 common->fsg = new_fsg;
2385 /* Enable the endpoints */
2386 d = fsg_ep_desc(common->gadget,
2387 &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
2388 rc = enable_endpoint(common, fsg->bulk_in, d);
2391 fsg->bulk_in_enabled = 1;
2393 d = fsg_ep_desc(common->gadget,
2394 &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
2395 rc = enable_endpoint(common, fsg->bulk_out, d);
2398 fsg->bulk_out_enabled = 1;
2399 common->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
2400 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2402 /* Allocate the requests */
2403 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2404 struct fsg_buffhd *bh = &common->buffhds[i];
2406 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2409 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2412 bh->inreq->buf = bh->outreq->buf = bh->buf;
2413 bh->inreq->context = bh->outreq->context = bh;
2414 bh->inreq->complete = bulk_in_complete;
2415 bh->outreq->complete = bulk_out_complete;
2418 common->running = 1;
2419 for (i = 0; i < common->nluns; ++i)
2420 common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
2425 /****************************** ALT CONFIGS ******************************/
2428 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2430 struct fsg_dev *fsg = fsg_from_func(f);
2431 fsg->common->new_fsg = fsg;
2432 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2436 static void fsg_disable(struct usb_function *f)
2438 struct fsg_dev *fsg = fsg_from_func(f);
2439 fsg->common->new_fsg = NULL;
2440 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2444 /*-------------------------------------------------------------------------*/
2446 static void handle_exception(struct fsg_common *common)
2450 struct fsg_buffhd *bh;
2451 enum fsg_state old_state;
2452 struct fsg_lun *curlun;
2453 unsigned int exception_req_tag;
2455 /* Clear the existing signals. Anything but SIGUSR1 is converted
2456 * into a high-priority EXIT exception. */
2459 dequeue_signal_lock(current, ¤t->blocked, &info);
2462 if (sig != SIGUSR1) {
2463 if (common->state < FSG_STATE_EXIT)
2464 DBG(common, "Main thread exiting on signal\n");
2465 raise_exception(common, FSG_STATE_EXIT);
2469 /* Cancel all the pending transfers */
2470 if (likely(common->fsg)) {
2471 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2472 bh = &common->buffhds[i];
2474 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2475 if (bh->outreq_busy)
2476 usb_ep_dequeue(common->fsg->bulk_out,
2480 /* Wait until everything is idle */
2483 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2484 bh = &common->buffhds[i];
2485 num_active += bh->inreq_busy + bh->outreq_busy;
2487 if (num_active == 0)
2489 if (sleep_thread(common))
2493 /* Clear out the controller's fifos */
2494 if (common->fsg->bulk_in_enabled)
2495 usb_ep_fifo_flush(common->fsg->bulk_in);
2496 if (common->fsg->bulk_out_enabled)
2497 usb_ep_fifo_flush(common->fsg->bulk_out);
2500 /* Reset the I/O buffer states and pointers, the SCSI
2501 * state, and the exception. Then invoke the handler. */
2502 spin_lock_irq(&common->lock);
2504 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2505 bh = &common->buffhds[i];
2506 bh->state = BUF_STATE_EMPTY;
2508 common->next_buffhd_to_fill = &common->buffhds[0];
2509 common->next_buffhd_to_drain = &common->buffhds[0];
2510 exception_req_tag = common->exception_req_tag;
2511 old_state = common->state;
2513 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2514 common->state = FSG_STATE_STATUS_PHASE;
2516 for (i = 0; i < common->nluns; ++i) {
2517 curlun = &common->luns[i];
2518 curlun->prevent_medium_removal = 0;
2519 curlun->sense_data = SS_NO_SENSE;
2520 curlun->unit_attention_data = SS_NO_SENSE;
2521 curlun->sense_data_info = 0;
2522 curlun->info_valid = 0;
2524 common->state = FSG_STATE_IDLE;
2526 spin_unlock_irq(&common->lock);
2528 /* Carry out any extra actions required for the exception */
2529 switch (old_state) {
2530 case FSG_STATE_ABORT_BULK_OUT:
2531 send_status(common);
2532 spin_lock_irq(&common->lock);
2533 if (common->state == FSG_STATE_STATUS_PHASE)
2534 common->state = FSG_STATE_IDLE;
2535 spin_unlock_irq(&common->lock);
2538 case FSG_STATE_RESET:
2539 /* In case we were forced against our will to halt a
2540 * bulk endpoint, clear the halt now. (The SuperH UDC
2541 * requires this.) */
2542 if (!fsg_is_set(common))
2544 if (test_and_clear_bit(IGNORE_BULK_OUT,
2545 &common->fsg->atomic_bitflags))
2546 usb_ep_clear_halt(common->fsg->bulk_in);
2548 if (common->ep0_req_tag == exception_req_tag)
2549 ep0_queue(common); /* Complete the status stage */
2551 /* Technically this should go here, but it would only be
2552 * a waste of time. Ditto for the INTERFACE_CHANGE and
2553 * CONFIG_CHANGE cases. */
2554 /* for (i = 0; i < common->nluns; ++i) */
2555 /* common->luns[i].unit_attention_data = */
2556 /* SS_RESET_OCCURRED; */
2559 case FSG_STATE_CONFIG_CHANGE:
2560 do_set_interface(common, common->new_fsg);
2563 case FSG_STATE_EXIT:
2564 case FSG_STATE_TERMINATED:
2565 do_set_interface(common, NULL); /* Free resources */
2566 spin_lock_irq(&common->lock);
2567 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2568 spin_unlock_irq(&common->lock);
2571 case FSG_STATE_INTERFACE_CHANGE:
2572 case FSG_STATE_DISCONNECT:
2573 case FSG_STATE_COMMAND_PHASE:
2574 case FSG_STATE_DATA_PHASE:
2575 case FSG_STATE_STATUS_PHASE:
2576 case FSG_STATE_IDLE:
2582 /*-------------------------------------------------------------------------*/
2584 static int fsg_main_thread(void *common_)
2586 struct fsg_common *common = common_;
2588 /* Allow the thread to be killed by a signal, but set the signal mask
2589 * to block everything but INT, TERM, KILL, and USR1. */
2590 allow_signal(SIGINT);
2591 allow_signal(SIGTERM);
2592 allow_signal(SIGKILL);
2593 allow_signal(SIGUSR1);
2595 /* Allow the thread to be frozen */
2598 /* Arrange for userspace references to be interpreted as kernel
2599 * pointers. That way we can pass a kernel pointer to a routine
2600 * that expects a __user pointer and it will work okay. */
2604 while (common->state != FSG_STATE_TERMINATED) {
2605 if (exception_in_progress(common) || signal_pending(current)) {
2606 handle_exception(common);
2610 if (!common->running) {
2611 sleep_thread(common);
2615 if (get_next_command(common))
2618 spin_lock_irq(&common->lock);
2619 if (!exception_in_progress(common))
2620 common->state = FSG_STATE_DATA_PHASE;
2621 spin_unlock_irq(&common->lock);
2623 if (do_scsi_command(common) || finish_reply(common))
2626 spin_lock_irq(&common->lock);
2627 if (!exception_in_progress(common))
2628 common->state = FSG_STATE_STATUS_PHASE;
2629 spin_unlock_irq(&common->lock);
2631 if (send_status(common))
2634 spin_lock_irq(&common->lock);
2635 if (!exception_in_progress(common))
2636 common->state = FSG_STATE_IDLE;
2637 spin_unlock_irq(&common->lock);
2640 spin_lock_irq(&common->lock);
2641 common->thread_task = NULL;
2642 spin_unlock_irq(&common->lock);
2644 if (!common->ops || !common->ops->thread_exits
2645 || common->ops->thread_exits(common) < 0) {
2646 struct fsg_lun *curlun = common->luns;
2647 unsigned i = common->nluns;
2649 down_write(&common->filesem);
2650 for (; i--; ++curlun) {
2651 if (!fsg_lun_is_open(curlun))
2654 fsg_lun_close(curlun);
2655 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
2657 up_write(&common->filesem);
2660 /* Let fsg_unbind() know the thread has exited */
2661 complete_and_exit(&common->thread_notifier, 0);
2665 /*************************** DEVICE ATTRIBUTES ***************************/
2667 /* Write permission is checked per LUN in store_*() functions. */
2668 static DEVICE_ATTR(ro, 0644, fsg_show_ro, fsg_store_ro);
2669 static DEVICE_ATTR(nofua, 0644, fsg_show_nofua, fsg_store_nofua);
2670 static DEVICE_ATTR(file, 0644, fsg_show_file, fsg_store_file);
2673 /****************************** FSG COMMON ******************************/
2675 static void fsg_common_release(struct kref *ref);
2677 static void fsg_lun_release(struct device *dev)
2679 /* Nothing needs to be done */
2682 static inline void fsg_common_get(struct fsg_common *common)
2684 kref_get(&common->ref);
2687 static inline void fsg_common_put(struct fsg_common *common)
2689 kref_put(&common->ref, fsg_common_release);
2693 static struct fsg_common *fsg_common_init(struct fsg_common *common,
2694 struct usb_composite_dev *cdev,
2695 struct fsg_config *cfg)
2697 struct usb_gadget *gadget = cdev->gadget;
2698 struct fsg_buffhd *bh;
2699 struct fsg_lun *curlun;
2700 struct fsg_lun_config *lcfg;
2704 /* Find out how many LUNs there should be */
2706 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2707 dev_err(&gadget->dev, "invalid number of LUNs: %u\n", nluns);
2708 return ERR_PTR(-EINVAL);
2713 common = kzalloc(sizeof *common, GFP_KERNEL);
2715 return ERR_PTR(-ENOMEM);
2716 common->free_storage_on_release = 1;
2718 memset(common, 0, sizeof common);
2719 common->free_storage_on_release = 0;
2722 common->ops = cfg->ops;
2723 common->private_data = cfg->private_data;
2725 common->gadget = gadget;
2726 common->ep0 = gadget->ep0;
2727 common->ep0req = cdev->req;
2729 /* Maybe allocate device-global string IDs, and patch descriptors */
2730 if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
2731 rc = usb_string_id(cdev);
2732 if (unlikely(rc < 0))
2734 fsg_strings[FSG_STRING_INTERFACE].id = rc;
2735 fsg_intf_desc.iInterface = rc;
2738 /* Create the LUNs, open their backing files, and register the
2739 * LUN devices in sysfs. */
2740 curlun = kzalloc(nluns * sizeof *curlun, GFP_KERNEL);
2741 if (unlikely(!curlun)) {
2745 common->luns = curlun;
2747 init_rwsem(&common->filesem);
2749 for (i = 0, lcfg = cfg->luns; i < nluns; ++i, ++curlun, ++lcfg) {
2750 curlun->cdrom = !!lcfg->cdrom;
2751 curlun->ro = lcfg->cdrom || lcfg->ro;
2752 curlun->removable = lcfg->removable;
2753 curlun->dev.release = fsg_lun_release;
2754 curlun->dev.parent = &gadget->dev;
2755 /* curlun->dev.driver = &fsg_driver.driver; XXX */
2756 dev_set_drvdata(&curlun->dev, &common->filesem);
2757 dev_set_name(&curlun->dev,
2758 cfg->lun_name_format
2759 ? cfg->lun_name_format
2763 rc = device_register(&curlun->dev);
2765 INFO(common, "failed to register LUN%d: %d\n", i, rc);
2767 put_device(&curlun->dev);
2771 rc = device_create_file(&curlun->dev, &dev_attr_ro);
2774 rc = device_create_file(&curlun->dev, &dev_attr_file);
2777 rc = device_create_file(&curlun->dev, &dev_attr_nofua);
2781 if (lcfg->filename) {
2782 rc = fsg_lun_open(curlun, lcfg->filename);
2785 } else if (!curlun->removable) {
2786 ERROR(common, "no file given for LUN%d\n", i);
2791 common->nluns = nluns;
2794 /* Data buffers cyclic list */
2795 bh = common->buffhds;
2796 i = FSG_NUM_BUFFERS;
2797 goto buffhds_first_it;
2802 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2803 if (unlikely(!bh->buf)) {
2808 bh->next = common->buffhds;
2811 /* Prepare inquiryString */
2812 if (cfg->release != 0xffff) {
2815 i = usb_gadget_controller_number(gadget);
2819 WARNING(common, "controller '%s' not recognized\n",
2824 snprintf(common->inquiry_string, sizeof common->inquiry_string,
2825 "%-8s%-16s%04x", cfg->vendor_name ?: "Linux",
2826 /* Assume product name dependent on the first LUN */
2827 cfg->product_name ?: (common->luns->cdrom
2828 ? "File-Stor Gadget"
2829 : "File-CD Gadget"),
2833 /* Some peripheral controllers are known not to be able to
2834 * halt bulk endpoints correctly. If one of them is present,
2837 common->can_stall = cfg->can_stall &&
2838 !(gadget_is_at91(common->gadget));
2841 spin_lock_init(&common->lock);
2842 kref_init(&common->ref);
2845 /* Tell the thread to start working */
2846 common->thread_task =
2847 kthread_create(fsg_main_thread, common,
2848 cfg->thread_name ?: "file-storage");
2849 if (IS_ERR(common->thread_task)) {
2850 rc = PTR_ERR(common->thread_task);
2853 init_completion(&common->thread_notifier);
2854 init_waitqueue_head(&common->fsg_wait);
2858 INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2859 INFO(common, "Number of LUNs=%d\n", common->nluns);
2861 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2862 for (i = 0, nluns = common->nluns, curlun = common->luns;
2865 char *p = "(no medium)";
2866 if (fsg_lun_is_open(curlun)) {
2869 p = d_path(&curlun->filp->f_path,
2875 LINFO(curlun, "LUN: %s%s%sfile: %s\n",
2876 curlun->removable ? "removable " : "",
2877 curlun->ro ? "read only " : "",
2878 curlun->cdrom ? "CD-ROM " : "",
2883 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
2885 wake_up_process(common->thread_task);
2891 common->nluns = i + 1;
2893 common->state = FSG_STATE_TERMINATED; /* The thread is dead */
2894 /* Call fsg_common_release() directly, ref might be not
2896 fsg_common_release(&common->ref);
2901 static void fsg_common_release(struct kref *ref)
2903 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
2905 /* If the thread isn't already dead, tell it to exit now */
2906 if (common->state != FSG_STATE_TERMINATED) {
2907 raise_exception(common, FSG_STATE_EXIT);
2908 wait_for_completion(&common->thread_notifier);
2911 if (likely(common->luns)) {
2912 struct fsg_lun *lun = common->luns;
2913 unsigned i = common->nluns;
2915 /* In error recovery common->nluns may be zero. */
2916 for (; i; --i, ++lun) {
2917 device_remove_file(&lun->dev, &dev_attr_nofua);
2918 device_remove_file(&lun->dev, &dev_attr_ro);
2919 device_remove_file(&lun->dev, &dev_attr_file);
2921 device_unregister(&lun->dev);
2924 kfree(common->luns);
2928 struct fsg_buffhd *bh = common->buffhds;
2929 unsigned i = FSG_NUM_BUFFERS;
2932 } while (++bh, --i);
2935 if (common->free_storage_on_release)
2940 /*-------------------------------------------------------------------------*/
2943 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
2945 struct fsg_dev *fsg = fsg_from_func(f);
2946 struct fsg_common *common = fsg->common;
2948 DBG(fsg, "unbind\n");
2949 if (fsg->common->fsg == fsg) {
2950 fsg->common->new_fsg = NULL;
2951 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2952 /* FIXME: make interruptible or killable somehow? */
2953 wait_event(common->fsg_wait, common->fsg != fsg);
2956 fsg_common_put(common);
2957 usb_free_descriptors(fsg->function.descriptors);
2958 usb_free_descriptors(fsg->function.hs_descriptors);
2963 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
2965 struct fsg_dev *fsg = fsg_from_func(f);
2966 struct usb_gadget *gadget = c->cdev->gadget;
2970 fsg->gadget = gadget;
2973 i = usb_interface_id(c, f);
2976 fsg_intf_desc.bInterfaceNumber = i;
2977 fsg->interface_number = i;
2979 /* Find all the endpoints we will use */
2980 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
2983 ep->driver_data = fsg->common; /* claim the endpoint */
2986 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
2989 ep->driver_data = fsg->common; /* claim the endpoint */
2992 /* Copy descriptors */
2993 f->descriptors = usb_copy_descriptors(fsg_fs_function);
2994 if (unlikely(!f->descriptors))
2997 if (gadget_is_dualspeed(gadget)) {
2998 /* Assume endpoint addresses are the same for both speeds */
2999 fsg_hs_bulk_in_desc.bEndpointAddress =
3000 fsg_fs_bulk_in_desc.bEndpointAddress;
3001 fsg_hs_bulk_out_desc.bEndpointAddress =
3002 fsg_fs_bulk_out_desc.bEndpointAddress;
3003 f->hs_descriptors = usb_copy_descriptors(fsg_hs_function);
3004 if (unlikely(!f->hs_descriptors)) {
3005 usb_free_descriptors(f->descriptors);
3013 ERROR(fsg, "unable to autoconfigure all endpoints\n");
3018 /****************************** ADD FUNCTION ******************************/
3020 static struct usb_gadget_strings *fsg_strings_array[] = {
3025 static int fsg_bind_config(struct usb_composite_dev *cdev,
3026 struct usb_configuration *c,
3027 struct fsg_common *common)
3029 struct fsg_dev *fsg;
3032 fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
3036 fsg->function.name = FSG_DRIVER_DESC;
3037 fsg->function.strings = fsg_strings_array;
3038 fsg->function.bind = fsg_bind;
3039 fsg->function.unbind = fsg_unbind;
3040 fsg->function.setup = fsg_setup;
3041 fsg->function.set_alt = fsg_set_alt;
3042 fsg->function.disable = fsg_disable;
3044 fsg->common = common;
3045 /* Our caller holds a reference to common structure so we
3046 * don't have to be worry about it being freed until we return
3047 * from this function. So instead of incrementing counter now
3048 * and decrement in error recovery we increment it only when
3049 * call to usb_add_function() was successful. */
3051 rc = usb_add_function(c, &fsg->function);
3055 fsg_common_get(fsg->common);
3059 static inline int __deprecated __maybe_unused
3060 fsg_add(struct usb_composite_dev *cdev,
3061 struct usb_configuration *c,
3062 struct fsg_common *common)
3064 return fsg_bind_config(cdev, c, common);
3068 /************************* Module parameters *************************/
3071 struct fsg_module_parameters {
3072 char *file[FSG_MAX_LUNS];
3073 int ro[FSG_MAX_LUNS];
3074 int removable[FSG_MAX_LUNS];
3075 int cdrom[FSG_MAX_LUNS];
3076 int nofua[FSG_MAX_LUNS];
3078 unsigned int file_count, ro_count, removable_count, cdrom_count;
3079 unsigned int nofua_count;
3080 unsigned int luns; /* nluns */
3081 int stall; /* can_stall */
3085 #define _FSG_MODULE_PARAM_ARRAY(prefix, params, name, type, desc) \
3086 module_param_array_named(prefix ## name, params.name, type, \
3087 &prefix ## params.name ## _count, \
3089 MODULE_PARM_DESC(prefix ## name, desc)
3091 #define _FSG_MODULE_PARAM(prefix, params, name, type, desc) \
3092 module_param_named(prefix ## name, params.name, type, \
3094 MODULE_PARM_DESC(prefix ## name, desc)
3096 #define FSG_MODULE_PARAMETERS(prefix, params) \
3097 _FSG_MODULE_PARAM_ARRAY(prefix, params, file, charp, \
3098 "names of backing files or devices"); \
3099 _FSG_MODULE_PARAM_ARRAY(prefix, params, ro, bool, \
3100 "true to force read-only"); \
3101 _FSG_MODULE_PARAM_ARRAY(prefix, params, removable, bool, \
3102 "true to simulate removable media"); \
3103 _FSG_MODULE_PARAM_ARRAY(prefix, params, cdrom, bool, \
3104 "true to simulate CD-ROM instead of disk"); \
3105 _FSG_MODULE_PARAM_ARRAY(prefix, params, nofua, bool, \
3106 "true to ignore SCSI WRITE(10,12) FUA bit"); \
3107 _FSG_MODULE_PARAM(prefix, params, luns, uint, \
3108 "number of LUNs"); \
3109 _FSG_MODULE_PARAM(prefix, params, stall, bool, \
3110 "false to prevent bulk stalls")
3114 fsg_config_from_params(struct fsg_config *cfg,
3115 const struct fsg_module_parameters *params)
3117 struct fsg_lun_config *lun;
3120 /* Configure LUNs */
3122 min(params->luns ?: (params->file_count ?: 1u),
3123 (unsigned)FSG_MAX_LUNS);
3124 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3125 lun->ro = !!params->ro[i];
3126 lun->cdrom = !!params->cdrom[i];
3127 lun->removable = /* Removable by default */
3128 params->removable_count <= i || params->removable[i];
3130 params->file_count > i && params->file[i][0]
3135 /* Let MSF use defaults */
3136 cfg->lun_name_format = 0;
3137 cfg->thread_name = 0;
3138 cfg->vendor_name = 0;
3139 cfg->product_name = 0;
3140 cfg->release = 0xffff;
3143 cfg->private_data = NULL;
3146 cfg->can_stall = params->stall;
3149 static inline struct fsg_common *
3150 fsg_common_from_params(struct fsg_common *common,
3151 struct usb_composite_dev *cdev,
3152 const struct fsg_module_parameters *params)
3153 __attribute__((unused));
3154 static inline struct fsg_common *
3155 fsg_common_from_params(struct fsg_common *common,
3156 struct usb_composite_dev *cdev,
3157 const struct fsg_module_parameters *params)
3159 struct fsg_config cfg;
3160 fsg_config_from_params(&cfg, params);
3161 return fsg_common_init(common, cdev, &cfg);