2 * f_mass_storage.c -- Mass Storage USB Composite Function
4 * Copyright (C) 2003-2008 Alan Stern
5 * Copyright (C) 2009 Samsung Electronics
6 * Author: Michal Nazarewicz <mina86@mina86.com>
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions, and the following disclaimer,
14 * without modification.
15 * 2. Redistributions in binary form must reproduce the above copyright
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17 * documentation and/or other materials provided with the distribution.
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19 * to endorse or promote products derived from this software without
20 * specific prior written permission.
22 * ALTERNATIVELY, this software may be distributed under the terms of the
23 * GNU General Public License ("GPL") as published by the Free Software
24 * Foundation, either version 2 of that License or (at your option) any
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
28 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
29 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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35 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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37 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
41 * The Mass Storage Function acts as a USB Mass Storage device,
42 * appearing to the host as a disk drive or as a CD-ROM drive. In
43 * addition to providing an example of a genuinely useful composite
44 * function for a USB device, it also illustrates a technique of
45 * double-buffering for increased throughput.
47 * Function supports multiple logical units (LUNs). Backing storage
48 * for each LUN is provided by a regular file or a block device.
49 * Access for each LUN can be limited to read-only. Moreover, the
50 * function can indicate that LUN is removable and/or CD-ROM. (The
51 * later implies read-only access.)
53 * MSF is configured by specifying a fsg_config structure. It has the
56 * nluns Number of LUNs function have (anywhere from 1
57 * to FSG_MAX_LUNS which is 8).
58 * luns An array of LUN configuration values. This
59 * should be filled for each LUN that
60 * function will include (ie. for "nluns"
61 * LUNs). Each element of the array has
62 * the following fields:
63 * ->filename The path to the backing file for the LUN.
64 * Required if LUN is not marked as
66 * ->ro Flag specifying access to the LUN shall be
67 * read-only. This is implied if CD-ROM
68 * emulation is enabled as well as when
69 * it was impossible to open "filename"
71 * ->removable Flag specifying that LUN shall be indicated as
73 * ->cdrom Flag specifying that LUN shall be reported as
75 * ->nofua Flag specifying that FUA flag in SCSI WRITE(10,12)
76 * commands for this LUN shall be ignored.
80 * release Information used as a reply to INQUIRY
81 * request. To use default set to NULL,
82 * NULL, 0xffff respectively. The first
83 * field should be 8 and the second 16
86 * can_stall Set to permit function to halt bulk endpoints.
87 * Disabled on some USB devices known not
88 * to work correctly. You should set it
91 * If "removable" is not set for a LUN then a backing file must be
92 * specified. If it is set, then NULL filename means the LUN's medium
93 * is not loaded (an empty string as "filename" in the fsg_config
94 * structure causes error). The CD-ROM emulation includes a single
95 * data track and no audio tracks; hence there need be only one
96 * backing file per LUN.
99 * MSF includes support for module parameters. If gadget using it
100 * decides to use it, the following module parameters will be
103 * file=filename[,filename...]
104 * Names of the files or block devices used for
106 * ro=b[,b...] Default false, boolean for read-only access.
108 * Default false, boolean for removable media.
109 * cdrom=b[,b...] Default false, boolean for whether to emulate
111 * nofua=b[,b...] Default false, booleans for ignore FUA flag
112 * in SCSI WRITE(10,12) commands
113 * luns=N Default N = number of filenames, number of
115 * stall Default determined according to the type of
116 * USB device controller (usually true),
117 * boolean to permit the driver to halt
120 * The module parameters may be prefixed with some string. You need
121 * to consult gadget's documentation or source to verify whether it is
122 * using those module parameters and if it does what are the prefixes
123 * (look for FSG_MODULE_PARAMETERS() macro usage, what's inside it is
127 * Requirements are modest; only a bulk-in and a bulk-out endpoint are
128 * needed. The memory requirement amounts to two 16K buffers, size
129 * configurable by a parameter. Support is included for both
130 * full-speed and high-speed operation.
132 * Note that the driver is slightly non-portable in that it assumes a
133 * single memory/DMA buffer will be useable for bulk-in, bulk-out, and
134 * interrupt-in endpoints. With most device controllers this isn't an
135 * issue, but there may be some with hardware restrictions that prevent
136 * a buffer from being used by more than one endpoint.
139 * The pathnames of the backing files, the ro settings and nofua
140 * settings are available in the attribute files "file", "ro" and
141 * "nofua" in the lun<n> subdirectory of the gadget's sysfs directory.
142 * If the "removable" option is set, writing to these files will
143 * simulate ejecting/loading the medium (writing an empty line means
144 * eject) and adjusting a write-enable tab. Changes to the ro setting
145 * are not allowed when the medium is loaded or if CD-ROM emulation is
148 * When a LUN receive an "eject" SCSI request (Start/Stop Unit),
149 * if the LUN is removable, the backing file is released to simulate
153 * This function is heavily based on "File-backed Storage Gadget" by
154 * Alan Stern which in turn is heavily based on "Gadget Zero" by David
155 * Brownell. The driver's SCSI command interface was based on the
156 * "Information technology - Small Computer System Interface - 2"
157 * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
158 * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
159 * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
160 * was based on the "Universal Serial Bus Mass Storage Class UFI
161 * Command Specification" document, Revision 1.0, December 14, 1998,
163 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
169 * The MSF is fairly straightforward. There is a main kernel
170 * thread that handles most of the work. Interrupt routines field
171 * callbacks from the controller driver: bulk- and interrupt-request
172 * completion notifications, endpoint-0 events, and disconnect events.
173 * Completion events are passed to the main thread by wakeup calls. Many
174 * ep0 requests are handled at interrupt time, but SetInterface,
175 * SetConfiguration, and device reset requests are forwarded to the
176 * thread in the form of "exceptions" using SIGUSR1 signals (since they
177 * should interrupt any ongoing file I/O operations).
179 * The thread's main routine implements the standard command/data/status
180 * parts of a SCSI interaction. It and its subroutines are full of tests
181 * for pending signals/exceptions -- all this polling is necessary since
182 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
183 * indication that the driver really wants to be running in userspace.)
184 * An important point is that so long as the thread is alive it keeps an
185 * open reference to the backing file. This will prevent unmounting
186 * the backing file's underlying filesystem and could cause problems
187 * during system shutdown, for example. To prevent such problems, the
188 * thread catches INT, TERM, and KILL signals and converts them into
191 * In normal operation the main thread is started during the gadget's
192 * fsg_bind() callback and stopped during fsg_unbind(). But it can
193 * also exit when it receives a signal, and there's no point leaving
194 * the gadget running when the thread is dead. At of this moment, MSF
195 * provides no way to deregister the gadget when thread dies -- maybe
196 * a callback functions is needed.
198 * To provide maximum throughput, the driver uses a circular pipeline of
199 * buffer heads (struct fsg_buffhd). In principle the pipeline can be
200 * arbitrarily long; in practice the benefits don't justify having more
201 * than 2 stages (i.e., double buffering). But it helps to think of the
202 * pipeline as being a long one. Each buffer head contains a bulk-in and
203 * a bulk-out request pointer (since the buffer can be used for both
204 * output and input -- directions always are given from the host's
205 * point of view) as well as a pointer to the buffer and various state
208 * Use of the pipeline follows a simple protocol. There is a variable
209 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
210 * At any time that buffer head may still be in use from an earlier
211 * request, so each buffer head has a state variable indicating whether
212 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
213 * buffer head to be EMPTY, filling the buffer either by file I/O or by
214 * USB I/O (during which the buffer head is BUSY), and marking the buffer
215 * head FULL when the I/O is complete. Then the buffer will be emptied
216 * (again possibly by USB I/O, during which it is marked BUSY) and
217 * finally marked EMPTY again (possibly by a completion routine).
219 * A module parameter tells the driver to avoid stalling the bulk
220 * endpoints wherever the transport specification allows. This is
221 * necessary for some UDCs like the SuperH, which cannot reliably clear a
222 * halt on a bulk endpoint. However, under certain circumstances the
223 * Bulk-only specification requires a stall. In such cases the driver
224 * will halt the endpoint and set a flag indicating that it should clear
225 * the halt in software during the next device reset. Hopefully this
226 * will permit everything to work correctly. Furthermore, although the
227 * specification allows the bulk-out endpoint to halt when the host sends
228 * too much data, implementing this would cause an unavoidable race.
229 * The driver will always use the "no-stall" approach for OUT transfers.
231 * One subtle point concerns sending status-stage responses for ep0
232 * requests. Some of these requests, such as device reset, can involve
233 * interrupting an ongoing file I/O operation, which might take an
234 * arbitrarily long time. During that delay the host might give up on
235 * the original ep0 request and issue a new one. When that happens the
236 * driver should not notify the host about completion of the original
237 * request, as the host will no longer be waiting for it. So the driver
238 * assigns to each ep0 request a unique tag, and it keeps track of the
239 * tag value of the request associated with a long-running exception
240 * (device-reset, interface-change, or configuration-change). When the
241 * exception handler is finished, the status-stage response is submitted
242 * only if the current ep0 request tag is equal to the exception request
243 * tag. Thus only the most recently received ep0 request will get a
244 * status-stage response.
246 * Warning: This driver source file is too long. It ought to be split up
247 * into a header file plus about 3 separate .c files, to handle the details
248 * of the Gadget, USB Mass Storage, and SCSI protocols.
252 /* #define VERBOSE_DEBUG */
253 /* #define DUMP_MSGS */
255 #include <linux/blkdev.h>
256 #include <linux/completion.h>
257 #include <linux/dcache.h>
258 #include <linux/delay.h>
259 #include <linux/device.h>
260 #include <linux/fcntl.h>
261 #include <linux/file.h>
262 #include <linux/fs.h>
263 #include <linux/kref.h>
264 #include <linux/kthread.h>
265 #include <linux/limits.h>
266 #include <linux/rwsem.h>
267 #include <linux/slab.h>
268 #include <linux/spinlock.h>
269 #include <linux/string.h>
270 #include <linux/freezer.h>
271 #include <linux/utsname.h>
273 #include <linux/usb/ch9.h>
274 #include <linux/usb/gadget.h>
275 #include <linux/usb/composite.h>
277 #include "gadget_chips.h"
280 /*------------------------------------------------------------------------*/
282 #define FSG_DRIVER_DESC "Mass Storage Function"
283 #define FSG_DRIVER_VERSION "2009/09/11"
285 static const char fsg_string_interface[] = "Mass Storage";
287 #define FSG_NO_DEVICE_STRINGS 1
289 #define FSG_NO_INTR_EP 1
291 #include "storage_common.c"
294 /*-------------------------------------------------------------------------*/
299 /* FSF callback functions */
300 struct fsg_operations {
302 * Callback function to call when thread exits. If no
303 * callback is set or it returns value lower then zero MSF
304 * will force eject all LUNs it operates on (including those
305 * marked as non-removable or with prevent_medium_removal flag
308 int (*thread_exits)(struct fsg_common *common);
311 * Called prior to ejection. Negative return means error,
312 * zero means to continue with ejection, positive means not to
315 int (*pre_eject)(struct fsg_common *common,
316 struct fsg_lun *lun, int num);
318 * Called after ejection. Negative return means error, zero
319 * or positive is just a success.
321 int (*post_eject)(struct fsg_common *common,
322 struct fsg_lun *lun, int num);
325 /* Data shared by all the FSG instances. */
327 struct usb_gadget *gadget;
328 struct usb_composite_dev *cdev;
329 struct fsg_dev *fsg, *new_fsg;
330 wait_queue_head_t fsg_wait;
332 /* filesem protects: backing files in use */
333 struct rw_semaphore filesem;
335 /* lock protects: state, all the req_busy's */
338 struct usb_ep *ep0; /* Copy of gadget->ep0 */
339 struct usb_request *ep0req; /* Copy of cdev->req */
340 unsigned int ep0_req_tag;
342 struct fsg_buffhd *next_buffhd_to_fill;
343 struct fsg_buffhd *next_buffhd_to_drain;
344 struct fsg_buffhd *buffhds;
347 u8 cmnd[MAX_COMMAND_SIZE];
351 struct fsg_lun *luns;
352 struct fsg_lun *curlun;
354 unsigned int bulk_out_maxpacket;
355 enum fsg_state state; /* For exception handling */
356 unsigned int exception_req_tag;
358 enum data_direction data_dir;
360 u32 data_size_from_cmnd;
365 unsigned int can_stall:1;
366 unsigned int free_storage_on_release:1;
367 unsigned int phase_error:1;
368 unsigned int short_packet_received:1;
369 unsigned int bad_lun_okay:1;
370 unsigned int running:1;
372 int thread_wakeup_needed;
373 struct completion thread_notifier;
374 struct task_struct *thread_task;
376 /* Callback functions. */
377 const struct fsg_operations *ops;
378 /* Gadget's private data. */
382 * Vendor (8 chars), product (16 chars), release (4
383 * hexadecimal digits) and NUL byte
385 char inquiry_string[8 + 16 + 4 + 1];
392 struct fsg_lun_config {
393 const char *filename;
398 } luns[FSG_MAX_LUNS];
400 /* Callback functions. */
401 const struct fsg_operations *ops;
402 /* Gadget's private data. */
405 const char *vendor_name; /* 8 characters or less */
406 const char *product_name; /* 16 characters or less */
413 struct usb_function function;
414 struct usb_gadget *gadget; /* Copy of cdev->gadget */
415 struct fsg_common *common;
417 u16 interface_number;
419 unsigned int bulk_in_enabled:1;
420 unsigned int bulk_out_enabled:1;
422 unsigned long atomic_bitflags;
423 #define IGNORE_BULK_OUT 0
425 struct usb_ep *bulk_in;
426 struct usb_ep *bulk_out;
429 static inline int __fsg_is_set(struct fsg_common *common,
430 const char *func, unsigned line)
434 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
439 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
441 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
443 return container_of(f, struct fsg_dev, function);
446 typedef void (*fsg_routine_t)(struct fsg_dev *);
448 static int exception_in_progress(struct fsg_common *common)
450 return common->state > FSG_STATE_IDLE;
453 /* Make bulk-out requests be divisible by the maxpacket size */
454 static void set_bulk_out_req_length(struct fsg_common *common,
455 struct fsg_buffhd *bh, unsigned int length)
459 bh->bulk_out_intended_length = length;
460 rem = length % common->bulk_out_maxpacket;
462 length += common->bulk_out_maxpacket - rem;
463 bh->outreq->length = length;
467 /*-------------------------------------------------------------------------*/
469 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
473 if (ep == fsg->bulk_in)
475 else if (ep == fsg->bulk_out)
479 DBG(fsg, "%s set halt\n", name);
480 return usb_ep_set_halt(ep);
484 /*-------------------------------------------------------------------------*/
486 /* These routines may be called in process context or in_irq */
488 /* Caller must hold fsg->lock */
489 static void wakeup_thread(struct fsg_common *common)
491 /* Tell the main thread that something has happened */
492 common->thread_wakeup_needed = 1;
493 if (common->thread_task)
494 wake_up_process(common->thread_task);
497 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
502 * Do nothing if a higher-priority exception is already in progress.
503 * If a lower-or-equal priority exception is in progress, preempt it
504 * and notify the main thread by sending it a signal.
506 spin_lock_irqsave(&common->lock, flags);
507 if (common->state <= new_state) {
508 common->exception_req_tag = common->ep0_req_tag;
509 common->state = new_state;
510 if (common->thread_task)
511 send_sig_info(SIGUSR1, SEND_SIG_FORCED,
512 common->thread_task);
514 spin_unlock_irqrestore(&common->lock, flags);
518 /*-------------------------------------------------------------------------*/
520 static int ep0_queue(struct fsg_common *common)
524 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
525 common->ep0->driver_data = common;
526 if (rc != 0 && rc != -ESHUTDOWN) {
527 /* We can't do much more than wait for a reset */
528 WARNING(common, "error in submission: %s --> %d\n",
529 common->ep0->name, rc);
535 /*-------------------------------------------------------------------------*/
537 /* Completion handlers. These always run in_irq. */
539 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
541 struct fsg_common *common = ep->driver_data;
542 struct fsg_buffhd *bh = req->context;
544 if (req->status || req->actual != req->length)
545 DBG(common, "%s --> %d, %u/%u\n", __func__,
546 req->status, req->actual, req->length);
547 if (req->status == -ECONNRESET) /* Request was cancelled */
548 usb_ep_fifo_flush(ep);
550 /* Hold the lock while we update the request and buffer states */
552 spin_lock(&common->lock);
554 bh->state = BUF_STATE_EMPTY;
555 wakeup_thread(common);
556 spin_unlock(&common->lock);
559 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
561 struct fsg_common *common = ep->driver_data;
562 struct fsg_buffhd *bh = req->context;
564 dump_msg(common, "bulk-out", req->buf, req->actual);
565 if (req->status || req->actual != bh->bulk_out_intended_length)
566 DBG(common, "%s --> %d, %u/%u\n", __func__,
567 req->status, req->actual, bh->bulk_out_intended_length);
568 if (req->status == -ECONNRESET) /* Request was cancelled */
569 usb_ep_fifo_flush(ep);
571 /* Hold the lock while we update the request and buffer states */
573 spin_lock(&common->lock);
575 bh->state = BUF_STATE_FULL;
576 wakeup_thread(common);
577 spin_unlock(&common->lock);
580 static int fsg_setup(struct usb_function *f,
581 const struct usb_ctrlrequest *ctrl)
583 struct fsg_dev *fsg = fsg_from_func(f);
584 struct usb_request *req = fsg->common->ep0req;
585 u16 w_index = le16_to_cpu(ctrl->wIndex);
586 u16 w_value = le16_to_cpu(ctrl->wValue);
587 u16 w_length = le16_to_cpu(ctrl->wLength);
589 if (!fsg_is_set(fsg->common))
592 ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
595 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
597 switch (ctrl->bRequest) {
599 case US_BULK_RESET_REQUEST:
600 if (ctrl->bRequestType !=
601 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
603 if (w_index != fsg->interface_number || w_value != 0 ||
608 * Raise an exception to stop the current operation
609 * and reinitialize our state.
611 DBG(fsg, "bulk reset request\n");
612 raise_exception(fsg->common, FSG_STATE_RESET);
613 return DELAYED_STATUS;
615 case US_BULK_GET_MAX_LUN:
616 if (ctrl->bRequestType !=
617 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
619 if (w_index != fsg->interface_number || w_value != 0 ||
622 VDBG(fsg, "get max LUN\n");
623 *(u8 *)req->buf = fsg->common->nluns - 1;
625 /* Respond with data/status */
626 req->length = min((u16)1, w_length);
627 return ep0_queue(fsg->common);
631 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
632 ctrl->bRequestType, ctrl->bRequest,
633 le16_to_cpu(ctrl->wValue), w_index, w_length);
638 /*-------------------------------------------------------------------------*/
640 /* All the following routines run in process context */
642 /* Use this for bulk or interrupt transfers, not ep0 */
643 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
644 struct usb_request *req, int *pbusy,
645 enum fsg_buffer_state *state)
649 if (ep == fsg->bulk_in)
650 dump_msg(fsg, "bulk-in", req->buf, req->length);
652 spin_lock_irq(&fsg->common->lock);
654 *state = BUF_STATE_BUSY;
655 spin_unlock_irq(&fsg->common->lock);
656 rc = usb_ep_queue(ep, req, GFP_KERNEL);
659 *state = BUF_STATE_EMPTY;
661 /* We can't do much more than wait for a reset */
664 * Note: currently the net2280 driver fails zero-length
665 * submissions if DMA is enabled.
667 if (rc != -ESHUTDOWN &&
668 !(rc == -EOPNOTSUPP && req->length == 0))
669 WARNING(fsg, "error in submission: %s --> %d\n",
674 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
676 if (!fsg_is_set(common))
678 start_transfer(common->fsg, common->fsg->bulk_in,
679 bh->inreq, &bh->inreq_busy, &bh->state);
683 static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
685 if (!fsg_is_set(common))
687 start_transfer(common->fsg, common->fsg->bulk_out,
688 bh->outreq, &bh->outreq_busy, &bh->state);
692 static int sleep_thread(struct fsg_common *common)
696 /* Wait until a signal arrives or we are woken up */
699 set_current_state(TASK_INTERRUPTIBLE);
700 if (signal_pending(current)) {
704 if (common->thread_wakeup_needed)
708 __set_current_state(TASK_RUNNING);
709 common->thread_wakeup_needed = 0;
714 /*-------------------------------------------------------------------------*/
716 static int do_read(struct fsg_common *common)
718 struct fsg_lun *curlun = common->curlun;
720 struct fsg_buffhd *bh;
723 loff_t file_offset, file_offset_tmp;
728 * Get the starting Logical Block Address and check that it's
731 if (common->cmnd[0] == READ_6)
732 lba = get_unaligned_be24(&common->cmnd[1]);
734 lba = get_unaligned_be32(&common->cmnd[2]);
737 * We allow DPO (Disable Page Out = don't save data in the
738 * cache) and FUA (Force Unit Access = don't read from the
739 * cache), but we don't implement them.
741 if ((common->cmnd[1] & ~0x18) != 0) {
742 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
746 if (lba >= curlun->num_sectors) {
747 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
750 file_offset = ((loff_t) lba) << curlun->blkbits;
752 /* Carry out the file reads */
753 amount_left = common->data_size_from_cmnd;
754 if (unlikely(amount_left == 0))
755 return -EIO; /* No default reply */
759 * Figure out how much we need to read:
760 * Try to read the remaining amount.
761 * But don't read more than the buffer size.
762 * And don't try to read past the end of the file.
764 amount = min(amount_left, FSG_BUFLEN);
765 amount = min((loff_t)amount,
766 curlun->file_length - file_offset);
768 /* Wait for the next buffer to become available */
769 bh = common->next_buffhd_to_fill;
770 while (bh->state != BUF_STATE_EMPTY) {
771 rc = sleep_thread(common);
777 * If we were asked to read past the end of file,
778 * end with an empty buffer.
782 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
783 curlun->sense_data_info =
784 file_offset >> curlun->blkbits;
785 curlun->info_valid = 1;
786 bh->inreq->length = 0;
787 bh->state = BUF_STATE_FULL;
791 /* Perform the read */
792 file_offset_tmp = file_offset;
793 nread = vfs_read(curlun->filp,
794 (char __user *)bh->buf,
795 amount, &file_offset_tmp);
796 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
797 (unsigned long long)file_offset, (int)nread);
798 if (signal_pending(current))
802 LDBG(curlun, "error in file read: %d\n", (int)nread);
804 } else if (nread < amount) {
805 LDBG(curlun, "partial file read: %d/%u\n",
807 nread = round_down(nread, curlun->blksize);
809 file_offset += nread;
810 amount_left -= nread;
811 common->residue -= nread;
814 * Except at the end of the transfer, nread will be
815 * equal to the buffer size, which is divisible by the
816 * bulk-in maxpacket size.
818 bh->inreq->length = nread;
819 bh->state = BUF_STATE_FULL;
821 /* If an error occurred, report it and its position */
822 if (nread < amount) {
823 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
824 curlun->sense_data_info =
825 file_offset >> curlun->blkbits;
826 curlun->info_valid = 1;
830 if (amount_left == 0)
831 break; /* No more left to read */
833 /* Send this buffer and go read some more */
835 if (!start_in_transfer(common, bh))
836 /* Don't know what to do if common->fsg is NULL */
838 common->next_buffhd_to_fill = bh->next;
841 return -EIO; /* No default reply */
845 /*-------------------------------------------------------------------------*/
847 static int do_write(struct fsg_common *common)
849 struct fsg_lun *curlun = common->curlun;
851 struct fsg_buffhd *bh;
853 u32 amount_left_to_req, amount_left_to_write;
854 loff_t usb_offset, file_offset, file_offset_tmp;
860 curlun->sense_data = SS_WRITE_PROTECTED;
863 spin_lock(&curlun->filp->f_lock);
864 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
865 spin_unlock(&curlun->filp->f_lock);
868 * Get the starting Logical Block Address and check that it's
871 if (common->cmnd[0] == WRITE_6)
872 lba = get_unaligned_be24(&common->cmnd[1]);
874 lba = get_unaligned_be32(&common->cmnd[2]);
877 * We allow DPO (Disable Page Out = don't save data in the
878 * cache) and FUA (Force Unit Access = write directly to the
879 * medium). We don't implement DPO; we implement FUA by
880 * performing synchronous output.
882 if (common->cmnd[1] & ~0x18) {
883 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
886 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
887 spin_lock(&curlun->filp->f_lock);
888 curlun->filp->f_flags |= O_SYNC;
889 spin_unlock(&curlun->filp->f_lock);
892 if (lba >= curlun->num_sectors) {
893 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
897 /* Carry out the file writes */
899 file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
900 amount_left_to_req = common->data_size_from_cmnd;
901 amount_left_to_write = common->data_size_from_cmnd;
903 while (amount_left_to_write > 0) {
905 /* Queue a request for more data from the host */
906 bh = common->next_buffhd_to_fill;
907 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
910 * Figure out how much we want to get:
911 * Try to get the remaining amount,
912 * but not more than the buffer size.
914 amount = min(amount_left_to_req, FSG_BUFLEN);
916 /* Beyond the end of the backing file? */
917 if (usb_offset >= curlun->file_length) {
920 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
921 curlun->sense_data_info =
922 usb_offset >> curlun->blkbits;
923 curlun->info_valid = 1;
927 /* Get the next buffer */
928 usb_offset += amount;
929 common->usb_amount_left -= amount;
930 amount_left_to_req -= amount;
931 if (amount_left_to_req == 0)
935 * Except at the end of the transfer, amount will be
936 * equal to the buffer size, which is divisible by
937 * the bulk-out maxpacket size.
939 set_bulk_out_req_length(common, bh, amount);
940 if (!start_out_transfer(common, bh))
941 /* Dunno what to do if common->fsg is NULL */
943 common->next_buffhd_to_fill = bh->next;
947 /* Write the received data to the backing file */
948 bh = common->next_buffhd_to_drain;
949 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
950 break; /* We stopped early */
951 if (bh->state == BUF_STATE_FULL) {
953 common->next_buffhd_to_drain = bh->next;
954 bh->state = BUF_STATE_EMPTY;
956 /* Did something go wrong with the transfer? */
957 if (bh->outreq->status != 0) {
958 curlun->sense_data = SS_COMMUNICATION_FAILURE;
959 curlun->sense_data_info =
960 file_offset >> curlun->blkbits;
961 curlun->info_valid = 1;
965 amount = bh->outreq->actual;
966 if (curlun->file_length - file_offset < amount) {
968 "write %u @ %llu beyond end %llu\n",
969 amount, (unsigned long long)file_offset,
970 (unsigned long long)curlun->file_length);
971 amount = curlun->file_length - file_offset;
974 /* Don't accept excess data. The spec doesn't say
975 * what to do in this case. We'll ignore the error.
977 amount = min(amount, bh->bulk_out_intended_length);
979 /* Don't write a partial block */
980 amount = round_down(amount, curlun->blksize);
984 /* Perform the write */
985 file_offset_tmp = file_offset;
986 nwritten = vfs_write(curlun->filp,
987 (char __user *)bh->buf,
988 amount, &file_offset_tmp);
989 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
990 (unsigned long long)file_offset, (int)nwritten);
991 if (signal_pending(current))
992 return -EINTR; /* Interrupted! */
995 LDBG(curlun, "error in file write: %d\n",
998 } else if (nwritten < amount) {
999 LDBG(curlun, "partial file write: %d/%u\n",
1000 (int)nwritten, amount);
1001 nwritten = round_down(nwritten, curlun->blksize);
1003 file_offset += nwritten;
1004 amount_left_to_write -= nwritten;
1005 common->residue -= nwritten;
1007 /* If an error occurred, report it and its position */
1008 if (nwritten < amount) {
1009 curlun->sense_data = SS_WRITE_ERROR;
1010 curlun->sense_data_info =
1011 file_offset >> curlun->blkbits;
1012 curlun->info_valid = 1;
1017 /* Did the host decide to stop early? */
1018 if (bh->outreq->actual < bh->bulk_out_intended_length) {
1019 common->short_packet_received = 1;
1025 /* Wait for something to happen */
1026 rc = sleep_thread(common);
1031 return -EIO; /* No default reply */
1035 /*-------------------------------------------------------------------------*/
1037 static int do_synchronize_cache(struct fsg_common *common)
1039 struct fsg_lun *curlun = common->curlun;
1042 /* We ignore the requested LBA and write out all file's
1043 * dirty data buffers. */
1044 rc = fsg_lun_fsync_sub(curlun);
1046 curlun->sense_data = SS_WRITE_ERROR;
1051 /*-------------------------------------------------------------------------*/
1053 static void invalidate_sub(struct fsg_lun *curlun)
1055 struct file *filp = curlun->filp;
1056 struct inode *inode = filp->f_path.dentry->d_inode;
1059 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
1060 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
1063 static int do_verify(struct fsg_common *common)
1065 struct fsg_lun *curlun = common->curlun;
1067 u32 verification_length;
1068 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1069 loff_t file_offset, file_offset_tmp;
1071 unsigned int amount;
1075 * Get the starting Logical Block Address and check that it's
1078 lba = get_unaligned_be32(&common->cmnd[2]);
1079 if (lba >= curlun->num_sectors) {
1080 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1085 * We allow DPO (Disable Page Out = don't save data in the
1086 * cache) but we don't implement it.
1088 if (common->cmnd[1] & ~0x10) {
1089 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1093 verification_length = get_unaligned_be16(&common->cmnd[7]);
1094 if (unlikely(verification_length == 0))
1095 return -EIO; /* No default reply */
1097 /* Prepare to carry out the file verify */
1098 amount_left = verification_length << curlun->blkbits;
1099 file_offset = ((loff_t) lba) << curlun->blkbits;
1101 /* Write out all the dirty buffers before invalidating them */
1102 fsg_lun_fsync_sub(curlun);
1103 if (signal_pending(current))
1106 invalidate_sub(curlun);
1107 if (signal_pending(current))
1110 /* Just try to read the requested blocks */
1111 while (amount_left > 0) {
1113 * Figure out how much we need to read:
1114 * Try to read the remaining amount, but not more than
1116 * And don't try to read past the end of the file.
1118 amount = min(amount_left, FSG_BUFLEN);
1119 amount = min((loff_t)amount,
1120 curlun->file_length - file_offset);
1122 curlun->sense_data =
1123 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1124 curlun->sense_data_info =
1125 file_offset >> curlun->blkbits;
1126 curlun->info_valid = 1;
1130 /* Perform the read */
1131 file_offset_tmp = file_offset;
1132 nread = vfs_read(curlun->filp,
1133 (char __user *) bh->buf,
1134 amount, &file_offset_tmp);
1135 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1136 (unsigned long long) file_offset,
1138 if (signal_pending(current))
1142 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1144 } else if (nread < amount) {
1145 LDBG(curlun, "partial file verify: %d/%u\n",
1146 (int)nread, amount);
1147 nread = round_down(nread, curlun->blksize);
1150 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1151 curlun->sense_data_info =
1152 file_offset >> curlun->blkbits;
1153 curlun->info_valid = 1;
1156 file_offset += nread;
1157 amount_left -= nread;
1163 /*-------------------------------------------------------------------------*/
1165 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1167 struct fsg_lun *curlun = common->curlun;
1168 u8 *buf = (u8 *) bh->buf;
1170 if (!curlun) { /* Unsupported LUNs are okay */
1171 common->bad_lun_okay = 1;
1173 buf[0] = 0x7f; /* Unsupported, no device-type */
1174 buf[4] = 31; /* Additional length */
1178 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1179 buf[1] = curlun->removable ? 0x80 : 0;
1180 buf[2] = 2; /* ANSI SCSI level 2 */
1181 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1182 buf[4] = 31; /* Additional length */
1183 buf[5] = 0; /* No special options */
1186 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1190 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1192 struct fsg_lun *curlun = common->curlun;
1193 u8 *buf = (u8 *) bh->buf;
1198 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1200 * If a REQUEST SENSE command is received from an initiator
1201 * with a pending unit attention condition (before the target
1202 * generates the contingent allegiance condition), then the
1203 * target shall either:
1204 * a) report any pending sense data and preserve the unit
1205 * attention condition on the logical unit, or,
1206 * b) report the unit attention condition, may discard any
1207 * pending sense data, and clear the unit attention
1208 * condition on the logical unit for that initiator.
1210 * FSG normally uses option a); enable this code to use option b).
1213 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1214 curlun->sense_data = curlun->unit_attention_data;
1215 curlun->unit_attention_data = SS_NO_SENSE;
1219 if (!curlun) { /* Unsupported LUNs are okay */
1220 common->bad_lun_okay = 1;
1221 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1225 sd = curlun->sense_data;
1226 sdinfo = curlun->sense_data_info;
1227 valid = curlun->info_valid << 7;
1228 curlun->sense_data = SS_NO_SENSE;
1229 curlun->sense_data_info = 0;
1230 curlun->info_valid = 0;
1234 buf[0] = valid | 0x70; /* Valid, current error */
1236 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1237 buf[7] = 18 - 8; /* Additional sense length */
1243 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1245 struct fsg_lun *curlun = common->curlun;
1246 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1247 int pmi = common->cmnd[8];
1248 u8 *buf = (u8 *)bh->buf;
1250 /* Check the PMI and LBA fields */
1251 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1252 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1256 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1257 /* Max logical block */
1258 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1262 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1264 struct fsg_lun *curlun = common->curlun;
1265 int msf = common->cmnd[1] & 0x02;
1266 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1267 u8 *buf = (u8 *)bh->buf;
1269 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1270 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1273 if (lba >= curlun->num_sectors) {
1274 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1279 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1280 store_cdrom_address(&buf[4], msf, lba);
1284 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1286 struct fsg_lun *curlun = common->curlun;
1287 int msf = common->cmnd[1] & 0x02;
1288 int start_track = common->cmnd[6];
1289 u8 *buf = (u8 *)bh->buf;
1291 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1293 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1298 buf[1] = (20-2); /* TOC data length */
1299 buf[2] = 1; /* First track number */
1300 buf[3] = 1; /* Last track number */
1301 buf[5] = 0x16; /* Data track, copying allowed */
1302 buf[6] = 0x01; /* Only track is number 1 */
1303 store_cdrom_address(&buf[8], msf, 0);
1305 buf[13] = 0x16; /* Lead-out track is data */
1306 buf[14] = 0xAA; /* Lead-out track number */
1307 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1311 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1313 struct fsg_lun *curlun = common->curlun;
1314 int mscmnd = common->cmnd[0];
1315 u8 *buf = (u8 *) bh->buf;
1318 int changeable_values, all_pages;
1322 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1323 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1326 pc = common->cmnd[2] >> 6;
1327 page_code = common->cmnd[2] & 0x3f;
1329 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1332 changeable_values = (pc == 1);
1333 all_pages = (page_code == 0x3f);
1336 * Write the mode parameter header. Fixed values are: default
1337 * medium type, no cache control (DPOFUA), and no block descriptors.
1338 * The only variable value is the WriteProtect bit. We will fill in
1339 * the mode data length later.
1342 if (mscmnd == MODE_SENSE) {
1343 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1346 } else { /* MODE_SENSE_10 */
1347 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1349 limit = 65535; /* Should really be FSG_BUFLEN */
1352 /* No block descriptors */
1355 * The mode pages, in numerical order. The only page we support
1356 * is the Caching page.
1358 if (page_code == 0x08 || all_pages) {
1360 buf[0] = 0x08; /* Page code */
1361 buf[1] = 10; /* Page length */
1362 memset(buf+2, 0, 10); /* None of the fields are changeable */
1364 if (!changeable_values) {
1365 buf[2] = 0x04; /* Write cache enable, */
1366 /* Read cache not disabled */
1367 /* No cache retention priorities */
1368 put_unaligned_be16(0xffff, &buf[4]);
1369 /* Don't disable prefetch */
1370 /* Minimum prefetch = 0 */
1371 put_unaligned_be16(0xffff, &buf[8]);
1372 /* Maximum prefetch */
1373 put_unaligned_be16(0xffff, &buf[10]);
1374 /* Maximum prefetch ceiling */
1380 * Check that a valid page was requested and the mode data length
1384 if (!valid_page || len > limit) {
1385 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1389 /* Store the mode data length */
1390 if (mscmnd == MODE_SENSE)
1393 put_unaligned_be16(len - 2, buf0);
1397 static int do_start_stop(struct fsg_common *common)
1399 struct fsg_lun *curlun = common->curlun;
1404 } else if (!curlun->removable) {
1405 curlun->sense_data = SS_INVALID_COMMAND;
1407 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1408 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1409 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1413 loej = common->cmnd[4] & 0x02;
1414 start = common->cmnd[4] & 0x01;
1417 * Our emulation doesn't support mounting; the medium is
1418 * available for use as soon as it is loaded.
1421 if (!fsg_lun_is_open(curlun)) {
1422 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1428 /* Are we allowed to unload the media? */
1429 if (curlun->prevent_medium_removal) {
1430 LDBG(curlun, "unload attempt prevented\n");
1431 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1438 /* Simulate an unload/eject */
1439 if (common->ops && common->ops->pre_eject) {
1440 int r = common->ops->pre_eject(common, curlun,
1441 curlun - common->luns);
1442 if (unlikely(r < 0))
1448 up_read(&common->filesem);
1449 down_write(&common->filesem);
1450 fsg_lun_close(curlun);
1451 up_write(&common->filesem);
1452 down_read(&common->filesem);
1454 return common->ops && common->ops->post_eject
1455 ? min(0, common->ops->post_eject(common, curlun,
1456 curlun - common->luns))
1460 static int do_prevent_allow(struct fsg_common *common)
1462 struct fsg_lun *curlun = common->curlun;
1465 if (!common->curlun) {
1467 } else if (!common->curlun->removable) {
1468 common->curlun->sense_data = SS_INVALID_COMMAND;
1472 prevent = common->cmnd[4] & 0x01;
1473 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1474 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1478 if (curlun->prevent_medium_removal && !prevent)
1479 fsg_lun_fsync_sub(curlun);
1480 curlun->prevent_medium_removal = prevent;
1484 static int do_read_format_capacities(struct fsg_common *common,
1485 struct fsg_buffhd *bh)
1487 struct fsg_lun *curlun = common->curlun;
1488 u8 *buf = (u8 *) bh->buf;
1490 buf[0] = buf[1] = buf[2] = 0;
1491 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1494 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1495 /* Number of blocks */
1496 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1497 buf[4] = 0x02; /* Current capacity */
1501 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1503 struct fsg_lun *curlun = common->curlun;
1505 /* We don't support MODE SELECT */
1507 curlun->sense_data = SS_INVALID_COMMAND;
1512 /*-------------------------------------------------------------------------*/
1514 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1518 rc = fsg_set_halt(fsg, fsg->bulk_in);
1520 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1522 if (rc != -EAGAIN) {
1523 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1528 /* Wait for a short time and then try again */
1529 if (msleep_interruptible(100) != 0)
1531 rc = usb_ep_set_halt(fsg->bulk_in);
1536 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1540 DBG(fsg, "bulk-in set wedge\n");
1541 rc = usb_ep_set_wedge(fsg->bulk_in);
1543 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1545 if (rc != -EAGAIN) {
1546 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1551 /* Wait for a short time and then try again */
1552 if (msleep_interruptible(100) != 0)
1554 rc = usb_ep_set_wedge(fsg->bulk_in);
1559 static int throw_away_data(struct fsg_common *common)
1561 struct fsg_buffhd *bh;
1565 for (bh = common->next_buffhd_to_drain;
1566 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1567 bh = common->next_buffhd_to_drain) {
1569 /* Throw away the data in a filled buffer */
1570 if (bh->state == BUF_STATE_FULL) {
1572 bh->state = BUF_STATE_EMPTY;
1573 common->next_buffhd_to_drain = bh->next;
1575 /* A short packet or an error ends everything */
1576 if (bh->outreq->actual < bh->bulk_out_intended_length ||
1577 bh->outreq->status != 0) {
1578 raise_exception(common,
1579 FSG_STATE_ABORT_BULK_OUT);
1585 /* Try to submit another request if we need one */
1586 bh = common->next_buffhd_to_fill;
1587 if (bh->state == BUF_STATE_EMPTY
1588 && common->usb_amount_left > 0) {
1589 amount = min(common->usb_amount_left, FSG_BUFLEN);
1592 * Except at the end of the transfer, amount will be
1593 * equal to the buffer size, which is divisible by
1594 * the bulk-out maxpacket size.
1596 set_bulk_out_req_length(common, bh, amount);
1597 if (!start_out_transfer(common, bh))
1598 /* Dunno what to do if common->fsg is NULL */
1600 common->next_buffhd_to_fill = bh->next;
1601 common->usb_amount_left -= amount;
1605 /* Otherwise wait for something to happen */
1606 rc = sleep_thread(common);
1613 static int finish_reply(struct fsg_common *common)
1615 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1618 switch (common->data_dir) {
1620 break; /* Nothing to send */
1623 * If we don't know whether the host wants to read or write,
1624 * this must be CB or CBI with an unknown command. We mustn't
1625 * try to send or receive any data. So stall both bulk pipes
1626 * if we can and wait for a reset.
1628 case DATA_DIR_UNKNOWN:
1629 if (!common->can_stall) {
1631 } else if (fsg_is_set(common)) {
1632 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1633 rc = halt_bulk_in_endpoint(common->fsg);
1635 /* Don't know what to do if common->fsg is NULL */
1640 /* All but the last buffer of data must have already been sent */
1641 case DATA_DIR_TO_HOST:
1642 if (common->data_size == 0) {
1643 /* Nothing to send */
1645 /* Don't know what to do if common->fsg is NULL */
1646 } else if (!fsg_is_set(common)) {
1649 /* If there's no residue, simply send the last buffer */
1650 } else if (common->residue == 0) {
1651 bh->inreq->zero = 0;
1652 if (!start_in_transfer(common, bh))
1654 common->next_buffhd_to_fill = bh->next;
1657 * For Bulk-only, mark the end of the data with a short
1658 * packet. If we are allowed to stall, halt the bulk-in
1659 * endpoint. (Note: This violates the Bulk-Only Transport
1660 * specification, which requires us to pad the data if we
1661 * don't halt the endpoint. Presumably nobody will mind.)
1664 bh->inreq->zero = 1;
1665 if (!start_in_transfer(common, bh))
1667 common->next_buffhd_to_fill = bh->next;
1668 if (common->can_stall)
1669 rc = halt_bulk_in_endpoint(common->fsg);
1674 * We have processed all we want from the data the host has sent.
1675 * There may still be outstanding bulk-out requests.
1677 case DATA_DIR_FROM_HOST:
1678 if (common->residue == 0) {
1679 /* Nothing to receive */
1681 /* Did the host stop sending unexpectedly early? */
1682 } else if (common->short_packet_received) {
1683 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1687 * We haven't processed all the incoming data. Even though
1688 * we may be allowed to stall, doing so would cause a race.
1689 * The controller may already have ACK'ed all the remaining
1690 * bulk-out packets, in which case the host wouldn't see a
1691 * STALL. Not realizing the endpoint was halted, it wouldn't
1692 * clear the halt -- leading to problems later on.
1695 } else if (common->can_stall) {
1696 if (fsg_is_set(common))
1697 fsg_set_halt(common->fsg,
1698 common->fsg->bulk_out);
1699 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1704 * We can't stall. Read in the excess data and throw it
1708 rc = throw_away_data(common);
1715 static int send_status(struct fsg_common *common)
1717 struct fsg_lun *curlun = common->curlun;
1718 struct fsg_buffhd *bh;
1719 struct bulk_cs_wrap *csw;
1721 u8 status = US_BULK_STAT_OK;
1724 /* Wait for the next buffer to become available */
1725 bh = common->next_buffhd_to_fill;
1726 while (bh->state != BUF_STATE_EMPTY) {
1727 rc = sleep_thread(common);
1733 sd = curlun->sense_data;
1734 sdinfo = curlun->sense_data_info;
1735 } else if (common->bad_lun_okay)
1738 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1740 if (common->phase_error) {
1741 DBG(common, "sending phase-error status\n");
1742 status = US_BULK_STAT_PHASE;
1743 sd = SS_INVALID_COMMAND;
1744 } else if (sd != SS_NO_SENSE) {
1745 DBG(common, "sending command-failure status\n");
1746 status = US_BULK_STAT_FAIL;
1747 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1749 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1752 /* Store and send the Bulk-only CSW */
1753 csw = (void *)bh->buf;
1755 csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
1756 csw->Tag = common->tag;
1757 csw->Residue = cpu_to_le32(common->residue);
1758 csw->Status = status;
1760 bh->inreq->length = US_BULK_CS_WRAP_LEN;
1761 bh->inreq->zero = 0;
1762 if (!start_in_transfer(common, bh))
1763 /* Don't know what to do if common->fsg is NULL */
1766 common->next_buffhd_to_fill = bh->next;
1771 /*-------------------------------------------------------------------------*/
1774 * Check whether the command is properly formed and whether its data size
1775 * and direction agree with the values we already have.
1777 static int check_command(struct fsg_common *common, int cmnd_size,
1778 enum data_direction data_dir, unsigned int mask,
1779 int needs_medium, const char *name)
1782 int lun = common->cmnd[1] >> 5;
1783 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1785 struct fsg_lun *curlun;
1788 if (common->data_dir != DATA_DIR_UNKNOWN)
1789 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1791 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1792 name, cmnd_size, dirletter[(int) data_dir],
1793 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1796 * We can't reply at all until we know the correct data direction
1799 if (common->data_size_from_cmnd == 0)
1800 data_dir = DATA_DIR_NONE;
1801 if (common->data_size < common->data_size_from_cmnd) {
1803 * Host data size < Device data size is a phase error.
1804 * Carry out the command, but only transfer as much as
1807 common->data_size_from_cmnd = common->data_size;
1808 common->phase_error = 1;
1810 common->residue = common->data_size;
1811 common->usb_amount_left = common->data_size;
1813 /* Conflicting data directions is a phase error */
1814 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1815 common->phase_error = 1;
1819 /* Verify the length of the command itself */
1820 if (cmnd_size != common->cmnd_size) {
1823 * Special case workaround: There are plenty of buggy SCSI
1824 * implementations. Many have issues with cbw->Length
1825 * field passing a wrong command size. For those cases we
1826 * always try to work around the problem by using the length
1827 * sent by the host side provided it is at least as large
1828 * as the correct command length.
1829 * Examples of such cases would be MS-Windows, which issues
1830 * REQUEST SENSE with cbw->Length == 12 where it should
1831 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1832 * REQUEST SENSE with cbw->Length == 10 where it should
1835 if (cmnd_size <= common->cmnd_size) {
1836 DBG(common, "%s is buggy! Expected length %d "
1837 "but we got %d\n", name,
1838 cmnd_size, common->cmnd_size);
1839 cmnd_size = common->cmnd_size;
1841 common->phase_error = 1;
1846 /* Check that the LUN values are consistent */
1847 if (common->lun != lun)
1848 DBG(common, "using LUN %d from CBW, not LUN %d from CDB\n",
1852 curlun = common->curlun;
1854 if (common->cmnd[0] != REQUEST_SENSE) {
1855 curlun->sense_data = SS_NO_SENSE;
1856 curlun->sense_data_info = 0;
1857 curlun->info_valid = 0;
1860 common->bad_lun_okay = 0;
1863 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1864 * to use unsupported LUNs; all others may not.
1866 if (common->cmnd[0] != INQUIRY &&
1867 common->cmnd[0] != REQUEST_SENSE) {
1868 DBG(common, "unsupported LUN %d\n", common->lun);
1874 * If a unit attention condition exists, only INQUIRY and
1875 * REQUEST SENSE commands are allowed; anything else must fail.
1877 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1878 common->cmnd[0] != INQUIRY &&
1879 common->cmnd[0] != REQUEST_SENSE) {
1880 curlun->sense_data = curlun->unit_attention_data;
1881 curlun->unit_attention_data = SS_NO_SENSE;
1885 /* Check that only command bytes listed in the mask are non-zero */
1886 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1887 for (i = 1; i < cmnd_size; ++i) {
1888 if (common->cmnd[i] && !(mask & (1 << i))) {
1890 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1895 /* If the medium isn't mounted and the command needs to access
1896 * it, return an error. */
1897 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1898 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1905 /* wrapper of check_command for data size in blocks handling */
1906 static int check_command_size_in_blocks(struct fsg_common *common,
1907 int cmnd_size, enum data_direction data_dir,
1908 unsigned int mask, int needs_medium, const char *name)
1911 common->data_size_from_cmnd <<= common->curlun->blkbits;
1912 return check_command(common, cmnd_size, data_dir,
1913 mask, needs_medium, name);
1916 static int do_scsi_command(struct fsg_common *common)
1918 struct fsg_buffhd *bh;
1920 int reply = -EINVAL;
1922 static char unknown[16];
1926 /* Wait for the next buffer to become available for data or status */
1927 bh = common->next_buffhd_to_fill;
1928 common->next_buffhd_to_drain = bh;
1929 while (bh->state != BUF_STATE_EMPTY) {
1930 rc = sleep_thread(common);
1934 common->phase_error = 0;
1935 common->short_packet_received = 0;
1937 down_read(&common->filesem); /* We're using the backing file */
1938 switch (common->cmnd[0]) {
1941 common->data_size_from_cmnd = common->cmnd[4];
1942 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1946 reply = do_inquiry(common, bh);
1950 common->data_size_from_cmnd = common->cmnd[4];
1951 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1955 reply = do_mode_select(common, bh);
1958 case MODE_SELECT_10:
1959 common->data_size_from_cmnd =
1960 get_unaligned_be16(&common->cmnd[7]);
1961 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1965 reply = do_mode_select(common, bh);
1969 common->data_size_from_cmnd = common->cmnd[4];
1970 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1971 (1<<1) | (1<<2) | (1<<4), 0,
1974 reply = do_mode_sense(common, bh);
1978 common->data_size_from_cmnd =
1979 get_unaligned_be16(&common->cmnd[7]);
1980 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1981 (1<<1) | (1<<2) | (3<<7), 0,
1984 reply = do_mode_sense(common, bh);
1987 case ALLOW_MEDIUM_REMOVAL:
1988 common->data_size_from_cmnd = 0;
1989 reply = check_command(common, 6, DATA_DIR_NONE,
1991 "PREVENT-ALLOW MEDIUM REMOVAL");
1993 reply = do_prevent_allow(common);
1997 i = common->cmnd[4];
1998 common->data_size_from_cmnd = (i == 0) ? 256 : i;
1999 reply = check_command_size_in_blocks(common, 6,
2004 reply = do_read(common);
2008 common->data_size_from_cmnd =
2009 get_unaligned_be16(&common->cmnd[7]);
2010 reply = check_command_size_in_blocks(common, 10,
2012 (1<<1) | (0xf<<2) | (3<<7), 1,
2015 reply = do_read(common);
2019 common->data_size_from_cmnd =
2020 get_unaligned_be32(&common->cmnd[6]);
2021 reply = check_command_size_in_blocks(common, 12,
2023 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2026 reply = do_read(common);
2030 common->data_size_from_cmnd = 8;
2031 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2032 (0xf<<2) | (1<<8), 1,
2035 reply = do_read_capacity(common, bh);
2039 if (!common->curlun || !common->curlun->cdrom)
2041 common->data_size_from_cmnd =
2042 get_unaligned_be16(&common->cmnd[7]);
2043 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2044 (3<<7) | (0x1f<<1), 1,
2047 reply = do_read_header(common, bh);
2051 if (!common->curlun || !common->curlun->cdrom)
2053 common->data_size_from_cmnd =
2054 get_unaligned_be16(&common->cmnd[7]);
2055 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2059 reply = do_read_toc(common, bh);
2062 case READ_FORMAT_CAPACITIES:
2063 common->data_size_from_cmnd =
2064 get_unaligned_be16(&common->cmnd[7]);
2065 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2067 "READ FORMAT CAPACITIES");
2069 reply = do_read_format_capacities(common, bh);
2073 common->data_size_from_cmnd = common->cmnd[4];
2074 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2078 reply = do_request_sense(common, bh);
2082 common->data_size_from_cmnd = 0;
2083 reply = check_command(common, 6, DATA_DIR_NONE,
2087 reply = do_start_stop(common);
2090 case SYNCHRONIZE_CACHE:
2091 common->data_size_from_cmnd = 0;
2092 reply = check_command(common, 10, DATA_DIR_NONE,
2093 (0xf<<2) | (3<<7), 1,
2094 "SYNCHRONIZE CACHE");
2096 reply = do_synchronize_cache(common);
2099 case TEST_UNIT_READY:
2100 common->data_size_from_cmnd = 0;
2101 reply = check_command(common, 6, DATA_DIR_NONE,
2107 * Although optional, this command is used by MS-Windows. We
2108 * support a minimal version: BytChk must be 0.
2111 common->data_size_from_cmnd = 0;
2112 reply = check_command(common, 10, DATA_DIR_NONE,
2113 (1<<1) | (0xf<<2) | (3<<7), 1,
2116 reply = do_verify(common);
2120 i = common->cmnd[4];
2121 common->data_size_from_cmnd = (i == 0) ? 256 : i;
2122 reply = check_command_size_in_blocks(common, 6,
2127 reply = do_write(common);
2131 common->data_size_from_cmnd =
2132 get_unaligned_be16(&common->cmnd[7]);
2133 reply = check_command_size_in_blocks(common, 10,
2135 (1<<1) | (0xf<<2) | (3<<7), 1,
2138 reply = do_write(common);
2142 common->data_size_from_cmnd =
2143 get_unaligned_be32(&common->cmnd[6]);
2144 reply = check_command_size_in_blocks(common, 12,
2146 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2149 reply = do_write(common);
2153 * Some mandatory commands that we recognize but don't implement.
2154 * They don't mean much in this setting. It's left as an exercise
2155 * for anyone interested to implement RESERVE and RELEASE in terms
2161 case SEND_DIAGNOSTIC:
2166 common->data_size_from_cmnd = 0;
2167 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2168 reply = check_command(common, common->cmnd_size,
2169 DATA_DIR_UNKNOWN, ~0, 0, unknown);
2171 common->curlun->sense_data = SS_INVALID_COMMAND;
2176 up_read(&common->filesem);
2178 if (reply == -EINTR || signal_pending(current))
2181 /* Set up the single reply buffer for finish_reply() */
2182 if (reply == -EINVAL)
2183 reply = 0; /* Error reply length */
2184 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2185 reply = min((u32)reply, common->data_size_from_cmnd);
2186 bh->inreq->length = reply;
2187 bh->state = BUF_STATE_FULL;
2188 common->residue -= reply;
2189 } /* Otherwise it's already set */
2195 /*-------------------------------------------------------------------------*/
2197 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2199 struct usb_request *req = bh->outreq;
2200 struct bulk_cb_wrap *cbw = req->buf;
2201 struct fsg_common *common = fsg->common;
2203 /* Was this a real packet? Should it be ignored? */
2204 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2207 /* Is the CBW valid? */
2208 if (req->actual != US_BULK_CB_WRAP_LEN ||
2209 cbw->Signature != cpu_to_le32(
2211 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2213 le32_to_cpu(cbw->Signature));
2216 * The Bulk-only spec says we MUST stall the IN endpoint
2217 * (6.6.1), so it's unavoidable. It also says we must
2218 * retain this state until the next reset, but there's
2219 * no way to tell the controller driver it should ignore
2220 * Clear-Feature(HALT) requests.
2222 * We aren't required to halt the OUT endpoint; instead
2223 * we can simply accept and discard any data received
2224 * until the next reset.
2226 wedge_bulk_in_endpoint(fsg);
2227 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2231 /* Is the CBW meaningful? */
2232 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~US_BULK_FLAG_IN ||
2233 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2234 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2236 cbw->Lun, cbw->Flags, cbw->Length);
2239 * We can do anything we want here, so let's stall the
2240 * bulk pipes if we are allowed to.
2242 if (common->can_stall) {
2243 fsg_set_halt(fsg, fsg->bulk_out);
2244 halt_bulk_in_endpoint(fsg);
2249 /* Save the command for later */
2250 common->cmnd_size = cbw->Length;
2251 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2252 if (cbw->Flags & US_BULK_FLAG_IN)
2253 common->data_dir = DATA_DIR_TO_HOST;
2255 common->data_dir = DATA_DIR_FROM_HOST;
2256 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2257 if (common->data_size == 0)
2258 common->data_dir = DATA_DIR_NONE;
2259 common->lun = cbw->Lun;
2260 if (common->lun >= 0 && common->lun < common->nluns)
2261 common->curlun = &common->luns[common->lun];
2263 common->curlun = NULL;
2264 common->tag = cbw->Tag;
2268 static int get_next_command(struct fsg_common *common)
2270 struct fsg_buffhd *bh;
2273 /* Wait for the next buffer to become available */
2274 bh = common->next_buffhd_to_fill;
2275 while (bh->state != BUF_STATE_EMPTY) {
2276 rc = sleep_thread(common);
2281 /* Queue a request to read a Bulk-only CBW */
2282 set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
2283 if (!start_out_transfer(common, bh))
2284 /* Don't know what to do if common->fsg is NULL */
2288 * We will drain the buffer in software, which means we
2289 * can reuse it for the next filling. No need to advance
2290 * next_buffhd_to_fill.
2293 /* Wait for the CBW to arrive */
2294 while (bh->state != BUF_STATE_FULL) {
2295 rc = sleep_thread(common);
2300 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2301 bh->state = BUF_STATE_EMPTY;
2307 /*-------------------------------------------------------------------------*/
2309 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2310 struct usb_request **preq)
2312 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2315 ERROR(common, "can't allocate request for %s\n", ep->name);
2319 /* Reset interface setting and re-init endpoint state (toggle etc). */
2320 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2322 struct fsg_dev *fsg;
2325 if (common->running)
2326 DBG(common, "reset interface\n");
2329 /* Deallocate the requests */
2333 for (i = 0; i < fsg_num_buffers; ++i) {
2334 struct fsg_buffhd *bh = &common->buffhds[i];
2337 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2341 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2346 /* Disable the endpoints */
2347 if (fsg->bulk_in_enabled) {
2348 usb_ep_disable(fsg->bulk_in);
2349 fsg->bulk_in_enabled = 0;
2351 if (fsg->bulk_out_enabled) {
2352 usb_ep_disable(fsg->bulk_out);
2353 fsg->bulk_out_enabled = 0;
2357 wake_up(&common->fsg_wait);
2360 common->running = 0;
2364 common->fsg = new_fsg;
2367 /* Enable the endpoints */
2368 rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
2371 rc = usb_ep_enable(fsg->bulk_in);
2374 fsg->bulk_in->driver_data = common;
2375 fsg->bulk_in_enabled = 1;
2377 rc = config_ep_by_speed(common->gadget, &(fsg->function),
2381 rc = usb_ep_enable(fsg->bulk_out);
2384 fsg->bulk_out->driver_data = common;
2385 fsg->bulk_out_enabled = 1;
2386 common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc);
2387 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2389 /* Allocate the requests */
2390 for (i = 0; i < fsg_num_buffers; ++i) {
2391 struct fsg_buffhd *bh = &common->buffhds[i];
2393 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2396 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2399 bh->inreq->buf = bh->outreq->buf = bh->buf;
2400 bh->inreq->context = bh->outreq->context = bh;
2401 bh->inreq->complete = bulk_in_complete;
2402 bh->outreq->complete = bulk_out_complete;
2405 common->running = 1;
2406 for (i = 0; i < common->nluns; ++i)
2407 common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
2412 /****************************** ALT CONFIGS ******************************/
2414 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2416 struct fsg_dev *fsg = fsg_from_func(f);
2417 fsg->common->new_fsg = fsg;
2418 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2419 return USB_GADGET_DELAYED_STATUS;
2422 static void fsg_disable(struct usb_function *f)
2424 struct fsg_dev *fsg = fsg_from_func(f);
2425 fsg->common->new_fsg = NULL;
2426 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2430 /*-------------------------------------------------------------------------*/
2432 static void handle_exception(struct fsg_common *common)
2436 struct fsg_buffhd *bh;
2437 enum fsg_state old_state;
2438 struct fsg_lun *curlun;
2439 unsigned int exception_req_tag;
2442 * Clear the existing signals. Anything but SIGUSR1 is converted
2443 * into a high-priority EXIT exception.
2447 dequeue_signal_lock(current, ¤t->blocked, &info);
2450 if (sig != SIGUSR1) {
2451 if (common->state < FSG_STATE_EXIT)
2452 DBG(common, "Main thread exiting on signal\n");
2453 raise_exception(common, FSG_STATE_EXIT);
2457 /* Cancel all the pending transfers */
2458 if (likely(common->fsg)) {
2459 for (i = 0; i < fsg_num_buffers; ++i) {
2460 bh = &common->buffhds[i];
2462 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2463 if (bh->outreq_busy)
2464 usb_ep_dequeue(common->fsg->bulk_out,
2468 /* Wait until everything is idle */
2471 for (i = 0; i < fsg_num_buffers; ++i) {
2472 bh = &common->buffhds[i];
2473 num_active += bh->inreq_busy + bh->outreq_busy;
2475 if (num_active == 0)
2477 if (sleep_thread(common))
2481 /* Clear out the controller's fifos */
2482 if (common->fsg->bulk_in_enabled)
2483 usb_ep_fifo_flush(common->fsg->bulk_in);
2484 if (common->fsg->bulk_out_enabled)
2485 usb_ep_fifo_flush(common->fsg->bulk_out);
2489 * Reset the I/O buffer states and pointers, the SCSI
2490 * state, and the exception. Then invoke the handler.
2492 spin_lock_irq(&common->lock);
2494 for (i = 0; i < fsg_num_buffers; ++i) {
2495 bh = &common->buffhds[i];
2496 bh->state = BUF_STATE_EMPTY;
2498 common->next_buffhd_to_fill = &common->buffhds[0];
2499 common->next_buffhd_to_drain = &common->buffhds[0];
2500 exception_req_tag = common->exception_req_tag;
2501 old_state = common->state;
2503 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2504 common->state = FSG_STATE_STATUS_PHASE;
2506 for (i = 0; i < common->nluns; ++i) {
2507 curlun = &common->luns[i];
2508 curlun->prevent_medium_removal = 0;
2509 curlun->sense_data = SS_NO_SENSE;
2510 curlun->unit_attention_data = SS_NO_SENSE;
2511 curlun->sense_data_info = 0;
2512 curlun->info_valid = 0;
2514 common->state = FSG_STATE_IDLE;
2516 spin_unlock_irq(&common->lock);
2518 /* Carry out any extra actions required for the exception */
2519 switch (old_state) {
2520 case FSG_STATE_ABORT_BULK_OUT:
2521 send_status(common);
2522 spin_lock_irq(&common->lock);
2523 if (common->state == FSG_STATE_STATUS_PHASE)
2524 common->state = FSG_STATE_IDLE;
2525 spin_unlock_irq(&common->lock);
2528 case FSG_STATE_RESET:
2530 * In case we were forced against our will to halt a
2531 * bulk endpoint, clear the halt now. (The SuperH UDC
2534 if (!fsg_is_set(common))
2536 if (test_and_clear_bit(IGNORE_BULK_OUT,
2537 &common->fsg->atomic_bitflags))
2538 usb_ep_clear_halt(common->fsg->bulk_in);
2540 if (common->ep0_req_tag == exception_req_tag)
2541 ep0_queue(common); /* Complete the status stage */
2544 * Technically this should go here, but it would only be
2545 * a waste of time. Ditto for the INTERFACE_CHANGE and
2546 * CONFIG_CHANGE cases.
2548 /* for (i = 0; i < common->nluns; ++i) */
2549 /* common->luns[i].unit_attention_data = */
2550 /* SS_RESET_OCCURRED; */
2553 case FSG_STATE_CONFIG_CHANGE:
2554 do_set_interface(common, common->new_fsg);
2555 if (common->new_fsg)
2556 usb_composite_setup_continue(common->cdev);
2559 case FSG_STATE_EXIT:
2560 case FSG_STATE_TERMINATED:
2561 do_set_interface(common, NULL); /* Free resources */
2562 spin_lock_irq(&common->lock);
2563 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2564 spin_unlock_irq(&common->lock);
2567 case FSG_STATE_INTERFACE_CHANGE:
2568 case FSG_STATE_DISCONNECT:
2569 case FSG_STATE_COMMAND_PHASE:
2570 case FSG_STATE_DATA_PHASE:
2571 case FSG_STATE_STATUS_PHASE:
2572 case FSG_STATE_IDLE:
2578 /*-------------------------------------------------------------------------*/
2580 static int fsg_main_thread(void *common_)
2582 struct fsg_common *common = common_;
2585 * Allow the thread to be killed by a signal, but set the signal mask
2586 * to block everything but INT, TERM, KILL, and USR1.
2588 allow_signal(SIGINT);
2589 allow_signal(SIGTERM);
2590 allow_signal(SIGKILL);
2591 allow_signal(SIGUSR1);
2593 /* Allow the thread to be frozen */
2597 * Arrange for userspace references to be interpreted as kernel
2598 * pointers. That way we can pass a kernel pointer to a routine
2599 * 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);
2692 static struct fsg_common *fsg_common_init(struct fsg_common *common,
2693 struct usb_composite_dev *cdev,
2694 struct fsg_config *cfg)
2696 struct usb_gadget *gadget = cdev->gadget;
2697 struct fsg_buffhd *bh;
2698 struct fsg_lun *curlun;
2699 struct fsg_lun_config *lcfg;
2703 rc = fsg_num_buffers_validate();
2707 /* Find out how many LUNs there should be */
2709 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2710 dev_err(&gadget->dev, "invalid number of LUNs: %u\n", nluns);
2711 return ERR_PTR(-EINVAL);
2716 common = kzalloc(sizeof *common, GFP_KERNEL);
2718 return ERR_PTR(-ENOMEM);
2719 common->free_storage_on_release = 1;
2721 memset(common, 0, sizeof *common);
2722 common->free_storage_on_release = 0;
2725 common->buffhds = kcalloc(fsg_num_buffers,
2726 sizeof *(common->buffhds), GFP_KERNEL);
2727 if (!common->buffhds) {
2728 if (common->free_storage_on_release)
2730 return ERR_PTR(-ENOMEM);
2733 common->ops = cfg->ops;
2734 common->private_data = cfg->private_data;
2736 common->gadget = gadget;
2737 common->ep0 = gadget->ep0;
2738 common->ep0req = cdev->req;
2739 common->cdev = cdev;
2741 /* Maybe allocate device-global string IDs, and patch descriptors */
2742 if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
2743 rc = usb_string_id(cdev);
2744 if (unlikely(rc < 0))
2746 fsg_strings[FSG_STRING_INTERFACE].id = rc;
2747 fsg_intf_desc.iInterface = rc;
2751 * Create the LUNs, open their backing files, and register the
2752 * LUN devices in sysfs.
2754 curlun = kcalloc(nluns, sizeof(*curlun), GFP_KERNEL);
2755 if (unlikely(!curlun)) {
2759 common->luns = curlun;
2761 init_rwsem(&common->filesem);
2763 for (i = 0, lcfg = cfg->luns; i < nluns; ++i, ++curlun, ++lcfg) {
2764 curlun->cdrom = !!lcfg->cdrom;
2765 curlun->ro = lcfg->cdrom || lcfg->ro;
2766 curlun->initially_ro = curlun->ro;
2767 curlun->removable = lcfg->removable;
2768 curlun->dev.release = fsg_lun_release;
2769 curlun->dev.parent = &gadget->dev;
2770 /* curlun->dev.driver = &fsg_driver.driver; XXX */
2771 dev_set_drvdata(&curlun->dev, &common->filesem);
2772 dev_set_name(&curlun->dev, "lun%d", i);
2774 rc = device_register(&curlun->dev);
2776 INFO(common, "failed to register LUN%d: %d\n", i, rc);
2778 put_device(&curlun->dev);
2782 rc = device_create_file(&curlun->dev, &dev_attr_ro);
2785 rc = device_create_file(&curlun->dev, &dev_attr_file);
2788 rc = device_create_file(&curlun->dev, &dev_attr_nofua);
2792 if (lcfg->filename) {
2793 rc = fsg_lun_open(curlun, lcfg->filename);
2796 } else if (!curlun->removable) {
2797 ERROR(common, "no file given for LUN%d\n", i);
2802 common->nluns = nluns;
2804 /* Data buffers cyclic list */
2805 bh = common->buffhds;
2806 i = fsg_num_buffers;
2807 goto buffhds_first_it;
2812 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2813 if (unlikely(!bh->buf)) {
2818 bh->next = common->buffhds;
2820 /* Prepare inquiryString */
2821 if (cfg->release != 0xffff) {
2824 i = usb_gadget_controller_number(gadget);
2828 WARNING(common, "controller '%s' not recognized\n",
2833 snprintf(common->inquiry_string, sizeof common->inquiry_string,
2834 "%-8s%-16s%04x", cfg->vendor_name ?: "Linux",
2835 /* Assume product name dependent on the first LUN */
2836 cfg->product_name ?: (common->luns->cdrom
2837 ? "File-Stor Gadget"
2838 : "File-CD Gadget"),
2842 * Some peripheral controllers are known not to be able to
2843 * halt bulk endpoints correctly. If one of them is present,
2846 common->can_stall = cfg->can_stall &&
2847 !(gadget_is_at91(common->gadget));
2849 spin_lock_init(&common->lock);
2850 kref_init(&common->ref);
2852 /* Tell the thread to start working */
2853 common->thread_task =
2854 kthread_create(fsg_main_thread, common, "file-storage");
2855 if (IS_ERR(common->thread_task)) {
2856 rc = PTR_ERR(common->thread_task);
2859 init_completion(&common->thread_notifier);
2860 init_waitqueue_head(&common->fsg_wait);
2863 INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2864 INFO(common, "Number of LUNs=%d\n", common->nluns);
2866 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2867 for (i = 0, nluns = common->nluns, curlun = common->luns;
2870 char *p = "(no medium)";
2871 if (fsg_lun_is_open(curlun)) {
2874 p = d_path(&curlun->filp->f_path,
2880 LINFO(curlun, "LUN: %s%s%sfile: %s\n",
2881 curlun->removable ? "removable " : "",
2882 curlun->ro ? "read only " : "",
2883 curlun->cdrom ? "CD-ROM " : "",
2888 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
2890 wake_up_process(common->thread_task);
2895 common->nluns = i + 1;
2897 common->state = FSG_STATE_TERMINATED; /* The thread is dead */
2898 /* Call fsg_common_release() directly, ref might be not initialised. */
2899 fsg_common_release(&common->ref);
2903 static void fsg_common_release(struct kref *ref)
2905 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
2907 /* If the thread isn't already dead, tell it to exit now */
2908 if (common->state != FSG_STATE_TERMINATED) {
2909 raise_exception(common, FSG_STATE_EXIT);
2910 wait_for_completion(&common->thread_notifier);
2913 if (likely(common->luns)) {
2914 struct fsg_lun *lun = common->luns;
2915 unsigned i = common->nluns;
2917 /* In error recovery common->nluns may be zero. */
2918 for (; i; --i, ++lun) {
2919 device_remove_file(&lun->dev, &dev_attr_nofua);
2920 device_remove_file(&lun->dev, &dev_attr_ro);
2921 device_remove_file(&lun->dev, &dev_attr_file);
2923 device_unregister(&lun->dev);
2926 kfree(common->luns);
2930 struct fsg_buffhd *bh = common->buffhds;
2931 unsigned i = fsg_num_buffers;
2934 } while (++bh, --i);
2937 kfree(common->buffhds);
2938 if (common->free_storage_on_release)
2943 /*-------------------------------------------------------------------------*/
2945 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
2947 struct fsg_dev *fsg = fsg_from_func(f);
2948 struct fsg_common *common = fsg->common;
2950 DBG(fsg, "unbind\n");
2951 if (fsg->common->fsg == fsg) {
2952 fsg->common->new_fsg = NULL;
2953 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2954 /* FIXME: make interruptible or killable somehow? */
2955 wait_event(common->fsg_wait, common->fsg != fsg);
2958 fsg_common_put(common);
2959 usb_free_descriptors(fsg->function.descriptors);
2960 usb_free_descriptors(fsg->function.hs_descriptors);
2961 usb_free_descriptors(fsg->function.ss_descriptors);
2965 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
2967 struct fsg_dev *fsg = fsg_from_func(f);
2968 struct usb_gadget *gadget = c->cdev->gadget;
2972 fsg->gadget = gadget;
2975 i = usb_interface_id(c, f);
2978 fsg_intf_desc.bInterfaceNumber = i;
2979 fsg->interface_number = i;
2981 /* Find all the endpoints we will use */
2982 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
2985 ep->driver_data = fsg->common; /* claim the endpoint */
2988 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
2991 ep->driver_data = fsg->common; /* claim the endpoint */
2994 /* Copy descriptors */
2995 f->descriptors = usb_copy_descriptors(fsg_fs_function);
2996 if (unlikely(!f->descriptors))
2999 if (gadget_is_dualspeed(gadget)) {
3000 /* Assume endpoint addresses are the same for both speeds */
3001 fsg_hs_bulk_in_desc.bEndpointAddress =
3002 fsg_fs_bulk_in_desc.bEndpointAddress;
3003 fsg_hs_bulk_out_desc.bEndpointAddress =
3004 fsg_fs_bulk_out_desc.bEndpointAddress;
3005 f->hs_descriptors = usb_copy_descriptors(fsg_hs_function);
3006 if (unlikely(!f->hs_descriptors)) {
3007 usb_free_descriptors(f->descriptors);
3012 if (gadget_is_superspeed(gadget)) {
3015 /* Calculate bMaxBurst, we know packet size is 1024 */
3016 max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15);
3018 fsg_ss_bulk_in_desc.bEndpointAddress =
3019 fsg_fs_bulk_in_desc.bEndpointAddress;
3020 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
3022 fsg_ss_bulk_out_desc.bEndpointAddress =
3023 fsg_fs_bulk_out_desc.bEndpointAddress;
3024 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
3026 f->ss_descriptors = usb_copy_descriptors(fsg_ss_function);
3027 if (unlikely(!f->ss_descriptors)) {
3028 usb_free_descriptors(f->hs_descriptors);
3029 usb_free_descriptors(f->descriptors);
3037 ERROR(fsg, "unable to autoconfigure all endpoints\n");
3042 /****************************** ADD FUNCTION ******************************/
3044 static struct usb_gadget_strings *fsg_strings_array[] = {
3049 static int fsg_bind_config(struct usb_composite_dev *cdev,
3050 struct usb_configuration *c,
3051 struct fsg_common *common)
3053 struct fsg_dev *fsg;
3056 fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
3060 fsg->function.name = FSG_DRIVER_DESC;
3061 fsg->function.strings = fsg_strings_array;
3062 fsg->function.bind = fsg_bind;
3063 fsg->function.unbind = fsg_unbind;
3064 fsg->function.setup = fsg_setup;
3065 fsg->function.set_alt = fsg_set_alt;
3066 fsg->function.disable = fsg_disable;
3068 fsg->common = common;
3070 * Our caller holds a reference to common structure so we
3071 * don't have to be worry about it being freed until we return
3072 * from this function. So instead of incrementing counter now
3073 * and decrement in error recovery we increment it only when
3074 * call to usb_add_function() was successful.
3077 rc = usb_add_function(c, &fsg->function);
3081 fsg_common_get(fsg->common);
3086 /************************* Module parameters *************************/
3088 struct fsg_module_parameters {
3089 char *file[FSG_MAX_LUNS];
3090 bool ro[FSG_MAX_LUNS];
3091 bool removable[FSG_MAX_LUNS];
3092 bool cdrom[FSG_MAX_LUNS];
3093 bool nofua[FSG_MAX_LUNS];
3095 unsigned int file_count, ro_count, removable_count, cdrom_count;
3096 unsigned int nofua_count;
3097 unsigned int luns; /* nluns */
3098 bool stall; /* can_stall */
3101 #define _FSG_MODULE_PARAM_ARRAY(prefix, params, name, type, desc) \
3102 module_param_array_named(prefix ## name, params.name, type, \
3103 &prefix ## params.name ## _count, \
3105 MODULE_PARM_DESC(prefix ## name, desc)
3107 #define _FSG_MODULE_PARAM(prefix, params, name, type, desc) \
3108 module_param_named(prefix ## name, params.name, type, \
3110 MODULE_PARM_DESC(prefix ## name, desc)
3112 #define FSG_MODULE_PARAMETERS(prefix, params) \
3113 _FSG_MODULE_PARAM_ARRAY(prefix, params, file, charp, \
3114 "names of backing files or devices"); \
3115 _FSG_MODULE_PARAM_ARRAY(prefix, params, ro, bool, \
3116 "true to force read-only"); \
3117 _FSG_MODULE_PARAM_ARRAY(prefix, params, removable, bool, \
3118 "true to simulate removable media"); \
3119 _FSG_MODULE_PARAM_ARRAY(prefix, params, cdrom, bool, \
3120 "true to simulate CD-ROM instead of disk"); \
3121 _FSG_MODULE_PARAM_ARRAY(prefix, params, nofua, bool, \
3122 "true to ignore SCSI WRITE(10,12) FUA bit"); \
3123 _FSG_MODULE_PARAM(prefix, params, luns, uint, \
3124 "number of LUNs"); \
3125 _FSG_MODULE_PARAM(prefix, params, stall, bool, \
3126 "false to prevent bulk stalls")
3129 fsg_config_from_params(struct fsg_config *cfg,
3130 const struct fsg_module_parameters *params)
3132 struct fsg_lun_config *lun;
3135 /* Configure LUNs */
3137 min(params->luns ?: (params->file_count ?: 1u),
3138 (unsigned)FSG_MAX_LUNS);
3139 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3140 lun->ro = !!params->ro[i];
3141 lun->cdrom = !!params->cdrom[i];
3142 lun->removable = !!params->removable[i];
3144 params->file_count > i && params->file[i][0]
3149 /* Let MSF use defaults */
3150 cfg->vendor_name = 0;
3151 cfg->product_name = 0;
3152 cfg->release = 0xffff;
3155 cfg->private_data = NULL;
3158 cfg->can_stall = params->stall;
3161 static inline struct fsg_common *
3162 fsg_common_from_params(struct fsg_common *common,
3163 struct usb_composite_dev *cdev,
3164 const struct fsg_module_parameters *params)
3165 __attribute__((unused));
3166 static inline struct fsg_common *
3167 fsg_common_from_params(struct fsg_common *common,
3168 struct usb_composite_dev *cdev,
3169 const struct fsg_module_parameters *params)
3171 struct fsg_config cfg;
3172 fsg_config_from_params(&cfg, params);
3173 return fsg_common_init(common, cdev, &cfg);