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
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13 * notice, this list of conditions, and the following disclaimer,
14 * without modification.
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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
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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.
78 * lun_name_format A printf-like format for names of the LUN
79 * devices. This determines how the
80 * directory in sysfs will be named.
81 * Unless you are using several MSFs in
82 * a single gadget (as opposed to single
83 * MSF in many configurations) you may
84 * leave it as NULL (in which case
85 * "lun%d" will be used). In the format
86 * you can use "%d" to index LUNs for
87 * MSF's with more than one LUN. (Beware
88 * that there is only one integer given
89 * as an argument for the format and
90 * specifying invalid format may cause
91 * unspecified behaviour.)
92 * thread_name Name of the kernel thread process used by the
93 * MSF. You can safely set it to NULL
94 * (in which case default "file-storage"
99 * release Information used as a reply to INQUIRY
100 * request. To use default set to NULL,
101 * NULL, 0xffff respectively. The first
102 * field should be 8 and the second 16
103 * characters or less.
105 * can_stall Set to permit function to halt bulk endpoints.
106 * Disabled on some USB devices known not
107 * to work correctly. You should set it
110 * If "removable" is not set for a LUN then a backing file must be
111 * specified. If it is set, then NULL filename means the LUN's medium
112 * is not loaded (an empty string as "filename" in the fsg_config
113 * structure causes error). The CD-ROM emulation includes a single
114 * data track and no audio tracks; hence there need be only one
115 * backing file per LUN. Note also that the CD-ROM block length is
116 * set to 512 rather than the more common value 2048.
119 * MSF includes support for module parameters. If gadget using it
120 * decides to use it, the following module parameters will be
123 * file=filename[,filename...]
124 * Names of the files or block devices used for
126 * ro=b[,b...] Default false, boolean for read-only access.
128 * Default true, boolean for removable media.
129 * cdrom=b[,b...] Default false, boolean for whether to emulate
131 * nofua=b[,b...] Default false, booleans for ignore FUA flag
132 * in SCSI WRITE(10,12) commands
133 * luns=N Default N = number of filenames, number of
135 * stall Default determined according to the type of
136 * USB device controller (usually true),
137 * boolean to permit the driver to halt
140 * The module parameters may be prefixed with some string. You need
141 * to consult gadget's documentation or source to verify whether it is
142 * using those module parameters and if it does what are the prefixes
143 * (look for FSG_MODULE_PARAMETERS() macro usage, what's inside it is
147 * Requirements are modest; only a bulk-in and a bulk-out endpoint are
148 * needed. The memory requirement amounts to two 16K buffers, size
149 * configurable by a parameter. Support is included for both
150 * full-speed and high-speed operation.
152 * Note that the driver is slightly non-portable in that it assumes a
153 * single memory/DMA buffer will be useable for bulk-in, bulk-out, and
154 * interrupt-in endpoints. With most device controllers this isn't an
155 * issue, but there may be some with hardware restrictions that prevent
156 * a buffer from being used by more than one endpoint.
159 * The pathnames of the backing files and the ro settings are
160 * available in the attribute files "file" and "ro" in the lun<n> (or
161 * to be more precise in a directory which name comes from
162 * "lun_name_format" option!) subdirectory of the gadget's sysfs
163 * directory. If the "removable" option is set, writing to these
164 * files will simulate ejecting/loading the medium (writing an empty
165 * line means eject) and adjusting a write-enable tab. Changes to the
166 * ro setting are not allowed when the medium is loaded or if CD-ROM
167 * emulation is being used.
169 * When a LUN receive an "eject" SCSI request (Start/Stop Unit),
170 * if the LUN is removable, the backing file is released to simulate
174 * This function is heavily based on "File-backed Storage Gadget" by
175 * Alan Stern which in turn is heavily based on "Gadget Zero" by David
176 * Brownell. The driver's SCSI command interface was based on the
177 * "Information technology - Small Computer System Interface - 2"
178 * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
179 * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
180 * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
181 * was based on the "Universal Serial Bus Mass Storage Class UFI
182 * Command Specification" document, Revision 1.0, December 14, 1998,
184 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
190 * The MSF is fairly straightforward. There is a main kernel
191 * thread that handles most of the work. Interrupt routines field
192 * callbacks from the controller driver: bulk- and interrupt-request
193 * completion notifications, endpoint-0 events, and disconnect events.
194 * Completion events are passed to the main thread by wakeup calls. Many
195 * ep0 requests are handled at interrupt time, but SetInterface,
196 * SetConfiguration, and device reset requests are forwarded to the
197 * thread in the form of "exceptions" using SIGUSR1 signals (since they
198 * should interrupt any ongoing file I/O operations).
200 * The thread's main routine implements the standard command/data/status
201 * parts of a SCSI interaction. It and its subroutines are full of tests
202 * for pending signals/exceptions -- all this polling is necessary since
203 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
204 * indication that the driver really wants to be running in userspace.)
205 * An important point is that so long as the thread is alive it keeps an
206 * open reference to the backing file. This will prevent unmounting
207 * the backing file's underlying filesystem and could cause problems
208 * during system shutdown, for example. To prevent such problems, the
209 * thread catches INT, TERM, and KILL signals and converts them into
212 * In normal operation the main thread is started during the gadget's
213 * fsg_bind() callback and stopped during fsg_unbind(). But it can
214 * also exit when it receives a signal, and there's no point leaving
215 * the gadget running when the thread is dead. At of this moment, MSF
216 * provides no way to deregister the gadget when thread dies -- maybe
217 * a callback functions is needed.
219 * To provide maximum throughput, the driver uses a circular pipeline of
220 * buffer heads (struct fsg_buffhd). In principle the pipeline can be
221 * arbitrarily long; in practice the benefits don't justify having more
222 * than 2 stages (i.e., double buffering). But it helps to think of the
223 * pipeline as being a long one. Each buffer head contains a bulk-in and
224 * a bulk-out request pointer (since the buffer can be used for both
225 * output and input -- directions always are given from the host's
226 * point of view) as well as a pointer to the buffer and various state
229 * Use of the pipeline follows a simple protocol. There is a variable
230 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
231 * At any time that buffer head may still be in use from an earlier
232 * request, so each buffer head has a state variable indicating whether
233 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
234 * buffer head to be EMPTY, filling the buffer either by file I/O or by
235 * USB I/O (during which the buffer head is BUSY), and marking the buffer
236 * head FULL when the I/O is complete. Then the buffer will be emptied
237 * (again possibly by USB I/O, during which it is marked BUSY) and
238 * finally marked EMPTY again (possibly by a completion routine).
240 * A module parameter tells the driver to avoid stalling the bulk
241 * endpoints wherever the transport specification allows. This is
242 * necessary for some UDCs like the SuperH, which cannot reliably clear a
243 * halt on a bulk endpoint. However, under certain circumstances the
244 * Bulk-only specification requires a stall. In such cases the driver
245 * will halt the endpoint and set a flag indicating that it should clear
246 * the halt in software during the next device reset. Hopefully this
247 * will permit everything to work correctly. Furthermore, although the
248 * specification allows the bulk-out endpoint to halt when the host sends
249 * too much data, implementing this would cause an unavoidable race.
250 * The driver will always use the "no-stall" approach for OUT transfers.
252 * One subtle point concerns sending status-stage responses for ep0
253 * requests. Some of these requests, such as device reset, can involve
254 * interrupting an ongoing file I/O operation, which might take an
255 * arbitrarily long time. During that delay the host might give up on
256 * the original ep0 request and issue a new one. When that happens the
257 * driver should not notify the host about completion of the original
258 * request, as the host will no longer be waiting for it. So the driver
259 * assigns to each ep0 request a unique tag, and it keeps track of the
260 * tag value of the request associated with a long-running exception
261 * (device-reset, interface-change, or configuration-change). When the
262 * exception handler is finished, the status-stage response is submitted
263 * only if the current ep0 request tag is equal to the exception request
264 * tag. Thus only the most recently received ep0 request will get a
265 * status-stage response.
267 * Warning: This driver source file is too long. It ought to be split up
268 * into a header file plus about 3 separate .c files, to handle the details
269 * of the Gadget, USB Mass Storage, and SCSI protocols.
273 /* #define VERBOSE_DEBUG */
274 /* #define DUMP_MSGS */
276 #include <linux/blkdev.h>
277 #include <linux/completion.h>
278 #include <linux/dcache.h>
279 #include <linux/delay.h>
280 #include <linux/device.h>
281 #include <linux/fcntl.h>
282 #include <linux/file.h>
283 #include <linux/fs.h>
284 #include <linux/kref.h>
285 #include <linux/kthread.h>
286 #include <linux/limits.h>
287 #include <linux/rwsem.h>
288 #include <linux/slab.h>
289 #include <linux/spinlock.h>
290 #include <linux/string.h>
291 #include <linux/freezer.h>
292 #include <linux/utsname.h>
294 #include <linux/usb/ch9.h>
295 #include <linux/usb/gadget.h>
296 #include <linux/usb/composite.h>
298 #include "gadget_chips.h"
301 /*------------------------------------------------------------------------*/
303 #define FSG_DRIVER_DESC "Mass Storage Function"
304 #define FSG_DRIVER_VERSION "2009/09/11"
306 static const char fsg_string_interface[] = "Mass Storage";
308 #define FSG_NO_INTR_EP 1
309 #define FSG_NO_DEVICE_STRINGS 1
311 #define FSG_NO_INTR_EP 1
313 #include "storage_common.c"
316 /*-------------------------------------------------------------------------*/
321 /* FSF callback functions */
322 struct fsg_operations {
324 * Callback function to call when thread exits. If no
325 * callback is set or it returns value lower then zero MSF
326 * will force eject all LUNs it operates on (including those
327 * marked as non-removable or with prevent_medium_removal flag
330 int (*thread_exits)(struct fsg_common *common);
333 * Called prior to ejection. Negative return means error,
334 * 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);
340 * Called after ejection. Negative return means error, zero
341 * or positive is just a success.
343 int (*post_eject)(struct fsg_common *common,
344 struct fsg_lun *lun, int num);
347 /* Data shared by all the FSG instances. */
349 struct usb_gadget *gadget;
350 struct fsg_dev *fsg, *new_fsg;
351 wait_queue_head_t fsg_wait;
353 /* filesem protects: backing files in use */
354 struct rw_semaphore filesem;
356 /* lock protects: state, all the req_busy's */
359 struct usb_ep *ep0; /* Copy of gadget->ep0 */
360 struct usb_request *ep0req; /* Copy of cdev->req */
361 unsigned int ep0_req_tag;
363 struct fsg_buffhd *next_buffhd_to_fill;
364 struct fsg_buffhd *next_buffhd_to_drain;
365 struct fsg_buffhd buffhds[FSG_NUM_BUFFERS];
368 u8 cmnd[MAX_COMMAND_SIZE];
372 struct fsg_lun *luns;
373 struct fsg_lun *curlun;
375 unsigned int bulk_out_maxpacket;
376 enum fsg_state state; /* For exception handling */
377 unsigned int exception_req_tag;
379 enum data_direction data_dir;
381 u32 data_size_from_cmnd;
386 unsigned int can_stall:1;
387 unsigned int free_storage_on_release:1;
388 unsigned int phase_error:1;
389 unsigned int short_packet_received:1;
390 unsigned int bad_lun_okay:1;
391 unsigned int running:1;
393 int thread_wakeup_needed;
394 struct completion thread_notifier;
395 struct task_struct *thread_task;
397 /* Callback functions. */
398 const struct fsg_operations *ops;
399 /* Gadget's private data. */
403 * Vendor (8 chars), product (16 chars), release (4
404 * hexadecimal digits) and NUL byte
406 char inquiry_string[8 + 16 + 4 + 1];
413 struct fsg_lun_config {
414 const char *filename;
419 } luns[FSG_MAX_LUNS];
421 const char *lun_name_format;
422 const char *thread_name;
424 /* Callback functions. */
425 const struct fsg_operations *ops;
426 /* Gadget's private data. */
429 const char *vendor_name; /* 8 characters or less */
430 const char *product_name; /* 16 characters or less */
437 struct usb_function function;
438 struct usb_gadget *gadget; /* Copy of cdev->gadget */
439 struct fsg_common *common;
441 u16 interface_number;
443 unsigned int bulk_in_enabled:1;
444 unsigned int bulk_out_enabled:1;
446 unsigned long atomic_bitflags;
447 #define IGNORE_BULK_OUT 0
449 struct usb_ep *bulk_in;
450 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__))
465 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
467 return container_of(f, struct fsg_dev, function);
470 typedef void (*fsg_routine_t)(struct fsg_dev *);
472 static int exception_in_progress(struct fsg_common *common)
474 return common->state > FSG_STATE_IDLE;
477 /* Make bulk-out requests be divisible by the maxpacket size */
478 static void set_bulk_out_req_length(struct fsg_common *common,
479 struct fsg_buffhd *bh, unsigned int length)
483 bh->bulk_out_intended_length = length;
484 rem = length % common->bulk_out_maxpacket;
486 length += common->bulk_out_maxpacket - rem;
487 bh->outreq->length = length;
491 /*-------------------------------------------------------------------------*/
493 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
497 if (ep == fsg->bulk_in)
499 else if (ep == fsg->bulk_out)
503 DBG(fsg, "%s set halt\n", name);
504 return usb_ep_set_halt(ep);
508 /*-------------------------------------------------------------------------*/
510 /* These routines may be called in process context or in_irq */
512 /* Caller must hold fsg->lock */
513 static void wakeup_thread(struct fsg_common *common)
515 /* Tell the main thread that something has happened */
516 common->thread_wakeup_needed = 1;
517 if (common->thread_task)
518 wake_up_process(common->thread_task);
521 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
526 * Do nothing if a higher-priority exception is already in progress.
527 * If a lower-or-equal priority exception is in progress, preempt it
528 * 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);
559 /*-------------------------------------------------------------------------*/
561 /* Completion handlers. 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, bh->bulk_out_intended_length);
592 if (req->status == -ECONNRESET) /* Request was cancelled */
593 usb_ep_fifo_flush(ep);
595 /* Hold the lock while we update the request and buffer states */
597 spin_lock(&common->lock);
599 bh->state = BUF_STATE_FULL;
600 wakeup_thread(common);
601 spin_unlock(&common->lock);
604 static int fsg_setup(struct usb_function *f,
605 const struct usb_ctrlrequest *ctrl)
607 struct fsg_dev *fsg = fsg_from_func(f);
608 struct usb_request *req = fsg->common->ep0req;
609 u16 w_index = le16_to_cpu(ctrl->wIndex);
610 u16 w_value = le16_to_cpu(ctrl->wValue);
611 u16 w_length = le16_to_cpu(ctrl->wLength);
613 if (!fsg_is_set(fsg->common))
616 switch (ctrl->bRequest) {
618 case USB_BULK_RESET_REQUEST:
619 if (ctrl->bRequestType !=
620 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
622 if (w_index != fsg->interface_number || w_value != 0)
626 * Raise an exception to stop the current operation
627 * and reinitialize our state.
629 DBG(fsg, "bulk reset request\n");
630 raise_exception(fsg->common, FSG_STATE_RESET);
631 return DELAYED_STATUS;
633 case USB_BULK_GET_MAX_LUN_REQUEST:
634 if (ctrl->bRequestType !=
635 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
637 if (w_index != fsg->interface_number || w_value != 0)
639 VDBG(fsg, "get max LUN\n");
640 *(u8 *)req->buf = fsg->common->nluns - 1;
642 /* Respond with data/status */
643 req->length = min((u16)1, w_length);
644 return ep0_queue(fsg->common);
648 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
649 ctrl->bRequestType, ctrl->bRequest,
650 le16_to_cpu(ctrl->wValue), w_index, w_length);
655 /*-------------------------------------------------------------------------*/
657 /* All the following routines run in process context */
659 /* Use this for bulk or interrupt transfers, not ep0 */
660 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
661 struct usb_request *req, int *pbusy,
662 enum fsg_buffer_state *state)
666 if (ep == fsg->bulk_in)
667 dump_msg(fsg, "bulk-in", req->buf, req->length);
669 spin_lock_irq(&fsg->common->lock);
671 *state = BUF_STATE_BUSY;
672 spin_unlock_irq(&fsg->common->lock);
673 rc = usb_ep_queue(ep, req, GFP_KERNEL);
676 *state = BUF_STATE_EMPTY;
678 /* We can't do much more than wait for a reset */
681 * Note: currently the net2280 driver fails zero-length
682 * submissions if DMA is enabled.
684 if (rc != -ESHUTDOWN &&
685 !(rc == -EOPNOTSUPP && req->length == 0))
686 WARNING(fsg, "error in submission: %s --> %d\n",
691 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
693 if (!fsg_is_set(common))
695 start_transfer(common->fsg, common->fsg->bulk_in,
696 bh->inreq, &bh->inreq_busy, &bh->state);
700 static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
702 if (!fsg_is_set(common))
704 start_transfer(common->fsg, common->fsg->bulk_out,
705 bh->outreq, &bh->outreq_busy, &bh->state);
709 static int sleep_thread(struct fsg_common *common)
713 /* Wait until a signal arrives or we are woken up */
716 set_current_state(TASK_INTERRUPTIBLE);
717 if (signal_pending(current)) {
721 if (common->thread_wakeup_needed)
725 __set_current_state(TASK_RUNNING);
726 common->thread_wakeup_needed = 0;
731 /*-------------------------------------------------------------------------*/
733 static int do_read(struct fsg_common *common)
735 struct fsg_lun *curlun = common->curlun;
737 struct fsg_buffhd *bh;
740 loff_t file_offset, file_offset_tmp;
742 unsigned int partial_page;
746 * Get the starting Logical Block Address and check that it's
749 if (common->cmnd[0] == READ_6)
750 lba = get_unaligned_be24(&common->cmnd[1]);
752 lba = get_unaligned_be32(&common->cmnd[2]);
755 * We allow DPO (Disable Page Out = don't save data in the
756 * cache) and FUA (Force Unit Access = don't read from the
757 * 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
786 amount = min(amount_left, FSG_BUFLEN);
787 amount = min((loff_t)amount,
788 curlun->file_length - file_offset);
789 partial_page = file_offset & (PAGE_CACHE_SIZE - 1);
790 if (partial_page > 0)
791 amount = min(amount, (unsigned int)PAGE_CACHE_SIZE -
794 /* Wait for the next buffer to become available */
795 bh = common->next_buffhd_to_fill;
796 while (bh->state != BUF_STATE_EMPTY) {
797 rc = sleep_thread(common);
803 * If we were asked to read past the end of file,
804 * end with an empty buffer.
808 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
809 curlun->sense_data_info = file_offset >> 9;
810 curlun->info_valid = 1;
811 bh->inreq->length = 0;
812 bh->state = BUF_STATE_FULL;
816 /* Perform the read */
817 file_offset_tmp = file_offset;
818 nread = vfs_read(curlun->filp,
819 (char __user *)bh->buf,
820 amount, &file_offset_tmp);
821 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
822 (unsigned long long)file_offset, (int)nread);
823 if (signal_pending(current))
827 LDBG(curlun, "error in file read: %d\n", (int)nread);
829 } else if (nread < amount) {
830 LDBG(curlun, "partial file read: %d/%u\n",
832 nread -= (nread & 511); /* Round down to a block */
834 file_offset += nread;
835 amount_left -= nread;
836 common->residue -= nread;
837 bh->inreq->length = nread;
838 bh->state = BUF_STATE_FULL;
840 /* If an error occurred, report it and its position */
841 if (nread < amount) {
842 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
843 curlun->sense_data_info = file_offset >> 9;
844 curlun->info_valid = 1;
848 if (amount_left == 0)
849 break; /* No more left to read */
851 /* Send this buffer and go read some more */
853 if (!start_in_transfer(common, bh))
854 /* Don't know what to do if common->fsg is NULL */
856 common->next_buffhd_to_fill = bh->next;
859 return -EIO; /* No default reply */
863 /*-------------------------------------------------------------------------*/
865 static int do_write(struct fsg_common *common)
867 struct fsg_lun *curlun = common->curlun;
869 struct fsg_buffhd *bh;
871 u32 amount_left_to_req, amount_left_to_write;
872 loff_t usb_offset, file_offset, file_offset_tmp;
874 unsigned int partial_page;
879 curlun->sense_data = SS_WRITE_PROTECTED;
882 spin_lock(&curlun->filp->f_lock);
883 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
884 spin_unlock(&curlun->filp->f_lock);
887 * Get the starting Logical Block Address and check that it's
890 if (common->cmnd[0] == WRITE_6)
891 lba = get_unaligned_be24(&common->cmnd[1]);
893 lba = get_unaligned_be32(&common->cmnd[2]);
896 * We allow DPO (Disable Page Out = don't save data in the
897 * cache) and FUA (Force Unit Access = write directly to the
898 * medium). We don't implement DPO; we implement FUA by
899 * performing synchronous output.
901 if (common->cmnd[1] & ~0x18) {
902 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
905 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
906 spin_lock(&curlun->filp->f_lock);
907 curlun->filp->f_flags |= O_SYNC;
908 spin_unlock(&curlun->filp->f_lock);
911 if (lba >= curlun->num_sectors) {
912 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
916 /* Carry out the file writes */
918 file_offset = usb_offset = ((loff_t) lba) << 9;
919 amount_left_to_req = common->data_size_from_cmnd;
920 amount_left_to_write = common->data_size_from_cmnd;
922 while (amount_left_to_write > 0) {
924 /* Queue a request for more data from the host */
925 bh = common->next_buffhd_to_fill;
926 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
929 * Figure out how much we want to get:
930 * Try to get the remaining amount.
931 * But don't get more than the buffer size.
932 * And don't try to go past the end of the file.
933 * If we're not at a page boundary,
934 * don't go past the next page.
935 * If this means getting 0, then we were asked
936 * to write past the end of file.
937 * Finally, round down to a block boundary.
939 amount = min(amount_left_to_req, FSG_BUFLEN);
940 amount = min((loff_t)amount,
941 curlun->file_length - usb_offset);
942 partial_page = usb_offset & (PAGE_CACHE_SIZE - 1);
943 if (partial_page > 0)
945 (unsigned int)PAGE_CACHE_SIZE - partial_page);
950 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
951 curlun->sense_data_info = usb_offset >> 9;
952 curlun->info_valid = 1;
955 amount -= amount & 511;
959 * Why were we were asked to transfer a
966 /* Get the next buffer */
967 usb_offset += amount;
968 common->usb_amount_left -= amount;
969 amount_left_to_req -= amount;
970 if (amount_left_to_req == 0)
974 * amount is always divisible by 512, hence by
975 * the bulk-out maxpacket size
977 bh->outreq->length = amount;
978 bh->bulk_out_intended_length = amount;
979 bh->outreq->short_not_ok = 1;
980 if (!start_out_transfer(common, bh))
981 /* Dunno what to do if common->fsg is NULL */
983 common->next_buffhd_to_fill = bh->next;
987 /* Write the received data to the backing file */
988 bh = common->next_buffhd_to_drain;
989 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
990 break; /* We stopped early */
991 if (bh->state == BUF_STATE_FULL) {
993 common->next_buffhd_to_drain = bh->next;
994 bh->state = BUF_STATE_EMPTY;
996 /* Did something go wrong with the transfer? */
997 if (bh->outreq->status != 0) {
998 curlun->sense_data = SS_COMMUNICATION_FAILURE;
999 curlun->sense_data_info = file_offset >> 9;
1000 curlun->info_valid = 1;
1004 amount = bh->outreq->actual;
1005 if (curlun->file_length - file_offset < amount) {
1007 "write %u @ %llu beyond end %llu\n",
1008 amount, (unsigned long long)file_offset,
1009 (unsigned long long)curlun->file_length);
1010 amount = curlun->file_length - file_offset;
1013 /* Perform the write */
1014 file_offset_tmp = file_offset;
1015 nwritten = vfs_write(curlun->filp,
1016 (char __user *)bh->buf,
1017 amount, &file_offset_tmp);
1018 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
1019 (unsigned long long)file_offset, (int)nwritten);
1020 if (signal_pending(current))
1021 return -EINTR; /* Interrupted! */
1024 LDBG(curlun, "error in file write: %d\n",
1027 } else if (nwritten < amount) {
1028 LDBG(curlun, "partial file write: %d/%u\n",
1029 (int)nwritten, amount);
1030 nwritten -= (nwritten & 511);
1031 /* Round down to a block */
1033 file_offset += nwritten;
1034 amount_left_to_write -= nwritten;
1035 common->residue -= nwritten;
1037 /* If an error occurred, report it and its position */
1038 if (nwritten < amount) {
1039 curlun->sense_data = SS_WRITE_ERROR;
1040 curlun->sense_data_info = file_offset >> 9;
1041 curlun->info_valid = 1;
1045 /* Did the host decide to stop early? */
1046 if (bh->outreq->actual != bh->outreq->length) {
1047 common->short_packet_received = 1;
1053 /* Wait for something to happen */
1054 rc = sleep_thread(common);
1059 return -EIO; /* No default reply */
1063 /*-------------------------------------------------------------------------*/
1065 static int do_synchronize_cache(struct fsg_common *common)
1067 struct fsg_lun *curlun = common->curlun;
1070 /* We ignore the requested LBA and write out all file's
1071 * dirty data buffers. */
1072 rc = fsg_lun_fsync_sub(curlun);
1074 curlun->sense_data = SS_WRITE_ERROR;
1079 /*-------------------------------------------------------------------------*/
1081 static void invalidate_sub(struct fsg_lun *curlun)
1083 struct file *filp = curlun->filp;
1084 struct inode *inode = filp->f_path.dentry->d_inode;
1087 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
1088 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
1091 static int do_verify(struct fsg_common *common)
1093 struct fsg_lun *curlun = common->curlun;
1095 u32 verification_length;
1096 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1097 loff_t file_offset, file_offset_tmp;
1099 unsigned int amount;
1103 * Get the starting Logical Block Address and check that it's
1106 lba = get_unaligned_be32(&common->cmnd[2]);
1107 if (lba >= curlun->num_sectors) {
1108 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1113 * We allow DPO (Disable Page Out = don't save data in the
1114 * cache) but we don't implement it.
1116 if (common->cmnd[1] & ~0x10) {
1117 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1121 verification_length = get_unaligned_be16(&common->cmnd[7]);
1122 if (unlikely(verification_length == 0))
1123 return -EIO; /* No default reply */
1125 /* Prepare to carry out the file verify */
1126 amount_left = verification_length << 9;
1127 file_offset = ((loff_t) lba) << 9;
1129 /* Write out all the dirty buffers before invalidating them */
1130 fsg_lun_fsync_sub(curlun);
1131 if (signal_pending(current))
1134 invalidate_sub(curlun);
1135 if (signal_pending(current))
1138 /* Just try to read the requested blocks */
1139 while (amount_left > 0) {
1141 * Figure out how much we need to read:
1142 * Try to read the remaining amount, but not more than
1144 * And don't try to read past the end of the file.
1145 * If this means reading 0 then we were asked to read
1146 * past the end of file.
1148 amount = min(amount_left, FSG_BUFLEN);
1149 amount = min((loff_t)amount,
1150 curlun->file_length - file_offset);
1152 curlun->sense_data =
1153 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1154 curlun->sense_data_info = file_offset >> 9;
1155 curlun->info_valid = 1;
1159 /* Perform the read */
1160 file_offset_tmp = file_offset;
1161 nread = vfs_read(curlun->filp,
1162 (char __user *) bh->buf,
1163 amount, &file_offset_tmp);
1164 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1165 (unsigned long long) file_offset,
1167 if (signal_pending(current))
1171 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1173 } else if (nread < amount) {
1174 LDBG(curlun, "partial file verify: %d/%u\n",
1175 (int)nread, amount);
1176 nread -= nread & 511; /* Round down to a sector */
1179 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1180 curlun->sense_data_info = file_offset >> 9;
1181 curlun->info_valid = 1;
1184 file_offset += nread;
1185 amount_left -= nread;
1191 /*-------------------------------------------------------------------------*/
1193 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1195 struct fsg_lun *curlun = common->curlun;
1196 u8 *buf = (u8 *) bh->buf;
1198 if (!curlun) { /* Unsupported LUNs are okay */
1199 common->bad_lun_okay = 1;
1201 buf[0] = 0x7f; /* Unsupported, no device-type */
1202 buf[4] = 31; /* Additional length */
1206 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1207 buf[1] = curlun->removable ? 0x80 : 0;
1208 buf[2] = 2; /* ANSI SCSI level 2 */
1209 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1210 buf[4] = 31; /* Additional length */
1211 buf[5] = 0; /* No special options */
1214 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1218 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1220 struct fsg_lun *curlun = common->curlun;
1221 u8 *buf = (u8 *) bh->buf;
1226 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1228 * If a REQUEST SENSE command is received from an initiator
1229 * with a pending unit attention condition (before the target
1230 * generates the contingent allegiance condition), then the
1231 * target shall either:
1232 * a) report any pending sense data and preserve the unit
1233 * attention condition on the logical unit, or,
1234 * b) report the unit attention condition, may discard any
1235 * pending sense data, and clear the unit attention
1236 * condition on the logical unit for that initiator.
1238 * FSG normally uses option a); enable this code to use option b).
1241 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1242 curlun->sense_data = curlun->unit_attention_data;
1243 curlun->unit_attention_data = SS_NO_SENSE;
1247 if (!curlun) { /* Unsupported LUNs are okay */
1248 common->bad_lun_okay = 1;
1249 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1253 sd = curlun->sense_data;
1254 sdinfo = curlun->sense_data_info;
1255 valid = curlun->info_valid << 7;
1256 curlun->sense_data = SS_NO_SENSE;
1257 curlun->sense_data_info = 0;
1258 curlun->info_valid = 0;
1262 buf[0] = valid | 0x70; /* Valid, current error */
1264 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1265 buf[7] = 18 - 8; /* Additional sense length */
1271 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1273 struct fsg_lun *curlun = common->curlun;
1274 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1275 int pmi = common->cmnd[8];
1276 u8 *buf = (u8 *)bh->buf;
1278 /* Check the PMI and LBA fields */
1279 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1280 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1284 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1285 /* Max logical block */
1286 put_unaligned_be32(512, &buf[4]); /* Block length */
1290 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1292 struct fsg_lun *curlun = common->curlun;
1293 int msf = common->cmnd[1] & 0x02;
1294 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1295 u8 *buf = (u8 *)bh->buf;
1297 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1298 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1301 if (lba >= curlun->num_sectors) {
1302 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1307 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1308 store_cdrom_address(&buf[4], msf, lba);
1312 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1314 struct fsg_lun *curlun = common->curlun;
1315 int msf = common->cmnd[1] & 0x02;
1316 int start_track = common->cmnd[6];
1317 u8 *buf = (u8 *)bh->buf;
1319 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1321 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1326 buf[1] = (20-2); /* TOC data length */
1327 buf[2] = 1; /* First track number */
1328 buf[3] = 1; /* Last track number */
1329 buf[5] = 0x16; /* Data track, copying allowed */
1330 buf[6] = 0x01; /* Only track is number 1 */
1331 store_cdrom_address(&buf[8], msf, 0);
1333 buf[13] = 0x16; /* Lead-out track is data */
1334 buf[14] = 0xAA; /* Lead-out track number */
1335 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1339 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1341 struct fsg_lun *curlun = common->curlun;
1342 int mscmnd = common->cmnd[0];
1343 u8 *buf = (u8 *) bh->buf;
1346 int changeable_values, all_pages;
1350 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1351 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1354 pc = common->cmnd[2] >> 6;
1355 page_code = common->cmnd[2] & 0x3f;
1357 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1360 changeable_values = (pc == 1);
1361 all_pages = (page_code == 0x3f);
1364 * Write the mode parameter header. Fixed values are: default
1365 * medium type, no cache control (DPOFUA), and no block descriptors.
1366 * The only variable value is the WriteProtect bit. We will fill in
1367 * the mode data length later.
1370 if (mscmnd == MODE_SENSE) {
1371 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1374 } else { /* MODE_SENSE_10 */
1375 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1377 limit = 65535; /* Should really be FSG_BUFLEN */
1380 /* No block descriptors */
1383 * The mode pages, in numerical order. The only page we support
1384 * is the Caching page.
1386 if (page_code == 0x08 || all_pages) {
1388 buf[0] = 0x08; /* Page code */
1389 buf[1] = 10; /* Page length */
1390 memset(buf+2, 0, 10); /* None of the fields are changeable */
1392 if (!changeable_values) {
1393 buf[2] = 0x04; /* Write cache enable, */
1394 /* Read cache not disabled */
1395 /* No cache retention priorities */
1396 put_unaligned_be16(0xffff, &buf[4]);
1397 /* Don't disable prefetch */
1398 /* Minimum prefetch = 0 */
1399 put_unaligned_be16(0xffff, &buf[8]);
1400 /* Maximum prefetch */
1401 put_unaligned_be16(0xffff, &buf[10]);
1402 /* Maximum prefetch ceiling */
1408 * Check that a valid page was requested and the mode data length
1412 if (!valid_page || len > limit) {
1413 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1417 /* Store the mode data length */
1418 if (mscmnd == MODE_SENSE)
1421 put_unaligned_be16(len - 2, buf0);
1425 static int do_start_stop(struct fsg_common *common)
1427 struct fsg_lun *curlun = common->curlun;
1432 } else if (!curlun->removable) {
1433 curlun->sense_data = SS_INVALID_COMMAND;
1435 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1436 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1437 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1441 loej = common->cmnd[4] & 0x02;
1442 start = common->cmnd[4] & 0x01;
1445 * Our emulation doesn't support mounting; the medium is
1446 * available for use as soon as it is loaded.
1449 if (!fsg_lun_is_open(curlun)) {
1450 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1456 /* Are we allowed to unload the media? */
1457 if (curlun->prevent_medium_removal) {
1458 LDBG(curlun, "unload attempt prevented\n");
1459 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1466 /* Simulate an unload/eject */
1467 if (common->ops && common->ops->pre_eject) {
1468 int r = common->ops->pre_eject(common, curlun,
1469 curlun - common->luns);
1470 if (unlikely(r < 0))
1476 up_read(&common->filesem);
1477 down_write(&common->filesem);
1478 fsg_lun_close(curlun);
1479 up_write(&common->filesem);
1480 down_read(&common->filesem);
1482 return common->ops && common->ops->post_eject
1483 ? min(0, common->ops->post_eject(common, curlun,
1484 curlun - common->luns))
1488 static int do_prevent_allow(struct fsg_common *common)
1490 struct fsg_lun *curlun = common->curlun;
1493 if (!common->curlun) {
1495 } else if (!common->curlun->removable) {
1496 common->curlun->sense_data = SS_INVALID_COMMAND;
1500 prevent = common->cmnd[4] & 0x01;
1501 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1502 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1506 if (curlun->prevent_medium_removal && !prevent)
1507 fsg_lun_fsync_sub(curlun);
1508 curlun->prevent_medium_removal = prevent;
1512 static int do_read_format_capacities(struct fsg_common *common,
1513 struct fsg_buffhd *bh)
1515 struct fsg_lun *curlun = common->curlun;
1516 u8 *buf = (u8 *) bh->buf;
1518 buf[0] = buf[1] = buf[2] = 0;
1519 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1522 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1523 /* Number of blocks */
1524 put_unaligned_be32(512, &buf[4]); /* Block length */
1525 buf[4] = 0x02; /* Current capacity */
1529 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1531 struct fsg_lun *curlun = common->curlun;
1533 /* We don't support MODE SELECT */
1535 curlun->sense_data = SS_INVALID_COMMAND;
1540 /*-------------------------------------------------------------------------*/
1542 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1546 rc = fsg_set_halt(fsg, fsg->bulk_in);
1548 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1550 if (rc != -EAGAIN) {
1551 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1556 /* Wait for a short time and then try again */
1557 if (msleep_interruptible(100) != 0)
1559 rc = usb_ep_set_halt(fsg->bulk_in);
1564 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1568 DBG(fsg, "bulk-in set wedge\n");
1569 rc = usb_ep_set_wedge(fsg->bulk_in);
1571 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1573 if (rc != -EAGAIN) {
1574 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1579 /* Wait for a short time and then try again */
1580 if (msleep_interruptible(100) != 0)
1582 rc = usb_ep_set_wedge(fsg->bulk_in);
1587 static int pad_with_zeros(struct fsg_dev *fsg)
1589 struct fsg_buffhd *bh = fsg->common->next_buffhd_to_fill;
1590 u32 nkeep = bh->inreq->length;
1594 bh->state = BUF_STATE_EMPTY; /* For the first iteration */
1595 fsg->common->usb_amount_left = nkeep + fsg->common->residue;
1596 while (fsg->common->usb_amount_left > 0) {
1598 /* Wait for the next buffer to be free */
1599 while (bh->state != BUF_STATE_EMPTY) {
1600 rc = sleep_thread(fsg->common);
1605 nsend = min(fsg->common->usb_amount_left, FSG_BUFLEN);
1606 memset(bh->buf + nkeep, 0, nsend - nkeep);
1607 bh->inreq->length = nsend;
1608 bh->inreq->zero = 0;
1609 start_transfer(fsg, fsg->bulk_in, bh->inreq,
1610 &bh->inreq_busy, &bh->state);
1611 bh = fsg->common->next_buffhd_to_fill = bh->next;
1612 fsg->common->usb_amount_left -= nsend;
1618 static int throw_away_data(struct fsg_common *common)
1620 struct fsg_buffhd *bh;
1624 for (bh = common->next_buffhd_to_drain;
1625 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1626 bh = common->next_buffhd_to_drain) {
1628 /* Throw away the data in a filled buffer */
1629 if (bh->state == BUF_STATE_FULL) {
1631 bh->state = BUF_STATE_EMPTY;
1632 common->next_buffhd_to_drain = bh->next;
1634 /* A short packet or an error ends everything */
1635 if (bh->outreq->actual != bh->outreq->length ||
1636 bh->outreq->status != 0) {
1637 raise_exception(common,
1638 FSG_STATE_ABORT_BULK_OUT);
1644 /* Try to submit another request if we need one */
1645 bh = common->next_buffhd_to_fill;
1646 if (bh->state == BUF_STATE_EMPTY
1647 && common->usb_amount_left > 0) {
1648 amount = min(common->usb_amount_left, FSG_BUFLEN);
1651 * amount is always divisible by 512, hence by
1652 * the bulk-out maxpacket size.
1654 bh->outreq->length = amount;
1655 bh->bulk_out_intended_length = amount;
1656 bh->outreq->short_not_ok = 1;
1657 if (!start_out_transfer(common, bh))
1658 /* Dunno what to do if common->fsg is NULL */
1660 common->next_buffhd_to_fill = bh->next;
1661 common->usb_amount_left -= amount;
1665 /* Otherwise wait for something to happen */
1666 rc = sleep_thread(common);
1673 static int finish_reply(struct fsg_common *common)
1675 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1678 switch (common->data_dir) {
1680 break; /* Nothing to send */
1683 * If we don't know whether the host wants to read or write,
1684 * this must be CB or CBI with an unknown command. We mustn't
1685 * try to send or receive any data. So stall both bulk pipes
1686 * if we can and wait for a reset.
1688 case DATA_DIR_UNKNOWN:
1689 if (!common->can_stall) {
1691 } else if (fsg_is_set(common)) {
1692 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1693 rc = halt_bulk_in_endpoint(common->fsg);
1695 /* Don't know what to do if common->fsg is NULL */
1700 /* All but the last buffer of data must have already been sent */
1701 case DATA_DIR_TO_HOST:
1702 if (common->data_size == 0) {
1703 /* Nothing to send */
1705 /* If there's no residue, simply send the last buffer */
1706 } else if (common->residue == 0) {
1707 bh->inreq->zero = 0;
1708 if (!start_in_transfer(common, bh))
1710 common->next_buffhd_to_fill = bh->next;
1713 * For Bulk-only, if we're allowed to stall then send the
1714 * short packet and halt the bulk-in endpoint. If we can't
1715 * stall, pad out the remaining data with 0's.
1717 } else if (common->can_stall) {
1718 bh->inreq->zero = 1;
1719 if (!start_in_transfer(common, bh))
1720 /* Don't know what to do if
1721 * common->fsg is NULL */
1723 common->next_buffhd_to_fill = bh->next;
1725 rc = halt_bulk_in_endpoint(common->fsg);
1726 } else if (fsg_is_set(common)) {
1727 rc = pad_with_zeros(common->fsg);
1729 /* Don't know what to do if common->fsg is NULL */
1735 * We have processed all we want from the data the host has sent.
1736 * There may still be outstanding bulk-out requests.
1738 case DATA_DIR_FROM_HOST:
1739 if (common->residue == 0) {
1740 /* Nothing to receive */
1742 /* Did the host stop sending unexpectedly early? */
1743 } else if (common->short_packet_received) {
1744 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1748 * We haven't processed all the incoming data. Even though
1749 * we may be allowed to stall, doing so would cause a race.
1750 * The controller may already have ACK'ed all the remaining
1751 * bulk-out packets, in which case the host wouldn't see a
1752 * STALL. Not realizing the endpoint was halted, it wouldn't
1753 * clear the halt -- leading to problems later on.
1756 } else if (common->can_stall) {
1757 if (fsg_is_set(common))
1758 fsg_set_halt(common->fsg,
1759 common->fsg->bulk_out);
1760 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1765 * We can't stall. Read in the excess data and throw it
1769 rc = throw_away_data(common);
1776 static int send_status(struct fsg_common *common)
1778 struct fsg_lun *curlun = common->curlun;
1779 struct fsg_buffhd *bh;
1780 struct bulk_cs_wrap *csw;
1782 u8 status = USB_STATUS_PASS;
1785 /* Wait for the next buffer to become available */
1786 bh = common->next_buffhd_to_fill;
1787 while (bh->state != BUF_STATE_EMPTY) {
1788 rc = sleep_thread(common);
1794 sd = curlun->sense_data;
1795 sdinfo = curlun->sense_data_info;
1796 } else if (common->bad_lun_okay)
1799 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1801 if (common->phase_error) {
1802 DBG(common, "sending phase-error status\n");
1803 status = USB_STATUS_PHASE_ERROR;
1804 sd = SS_INVALID_COMMAND;
1805 } else if (sd != SS_NO_SENSE) {
1806 DBG(common, "sending command-failure status\n");
1807 status = USB_STATUS_FAIL;
1808 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1810 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1813 /* Store and send the Bulk-only CSW */
1814 csw = (void *)bh->buf;
1816 csw->Signature = cpu_to_le32(USB_BULK_CS_SIG);
1817 csw->Tag = common->tag;
1818 csw->Residue = cpu_to_le32(common->residue);
1819 csw->Status = status;
1821 bh->inreq->length = USB_BULK_CS_WRAP_LEN;
1822 bh->inreq->zero = 0;
1823 if (!start_in_transfer(common, bh))
1824 /* Don't know what to do if common->fsg is NULL */
1827 common->next_buffhd_to_fill = bh->next;
1832 /*-------------------------------------------------------------------------*/
1835 * Check whether the command is properly formed and whether its data size
1836 * and direction agree with the values we already have.
1838 static int check_command(struct fsg_common *common, int cmnd_size,
1839 enum data_direction data_dir, unsigned int mask,
1840 int needs_medium, const char *name)
1843 int lun = common->cmnd[1] >> 5;
1844 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1846 struct fsg_lun *curlun;
1849 if (common->data_dir != DATA_DIR_UNKNOWN)
1850 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1852 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1853 name, cmnd_size, dirletter[(int) data_dir],
1854 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1857 * We can't reply at all until we know the correct data direction
1860 if (common->data_size_from_cmnd == 0)
1861 data_dir = DATA_DIR_NONE;
1862 if (common->data_size < common->data_size_from_cmnd) {
1864 * Host data size < Device data size is a phase error.
1865 * Carry out the command, but only transfer as much as
1868 common->data_size_from_cmnd = common->data_size;
1869 common->phase_error = 1;
1871 common->residue = common->data_size;
1872 common->usb_amount_left = common->data_size;
1874 /* Conflicting data directions is a phase error */
1875 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1876 common->phase_error = 1;
1880 /* Verify the length of the command itself */
1881 if (cmnd_size != common->cmnd_size) {
1884 * Special case workaround: There are plenty of buggy SCSI
1885 * implementations. Many have issues with cbw->Length
1886 * field passing a wrong command size. For those cases we
1887 * always try to work around the problem by using the length
1888 * sent by the host side provided it is at least as large
1889 * as the correct command length.
1890 * Examples of such cases would be MS-Windows, which issues
1891 * REQUEST SENSE with cbw->Length == 12 where it should
1892 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1893 * REQUEST SENSE with cbw->Length == 10 where it should
1896 if (cmnd_size <= common->cmnd_size) {
1897 DBG(common, "%s is buggy! Expected length %d "
1898 "but we got %d\n", name,
1899 cmnd_size, common->cmnd_size);
1900 cmnd_size = common->cmnd_size;
1902 common->phase_error = 1;
1907 /* Check that the LUN values are consistent */
1908 if (common->lun != lun)
1909 DBG(common, "using LUN %d from CBW, not LUN %d from CDB\n",
1913 if (common->lun >= 0 && common->lun < common->nluns) {
1914 curlun = &common->luns[common->lun];
1915 common->curlun = curlun;
1916 if (common->cmnd[0] != REQUEST_SENSE) {
1917 curlun->sense_data = SS_NO_SENSE;
1918 curlun->sense_data_info = 0;
1919 curlun->info_valid = 0;
1922 common->curlun = NULL;
1924 common->bad_lun_okay = 0;
1927 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1928 * to use unsupported LUNs; all others may not.
1930 if (common->cmnd[0] != INQUIRY &&
1931 common->cmnd[0] != REQUEST_SENSE) {
1932 DBG(common, "unsupported LUN %d\n", common->lun);
1938 * If a unit attention condition exists, only INQUIRY and
1939 * REQUEST SENSE commands are allowed; anything else must fail.
1941 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1942 common->cmnd[0] != INQUIRY &&
1943 common->cmnd[0] != REQUEST_SENSE) {
1944 curlun->sense_data = curlun->unit_attention_data;
1945 curlun->unit_attention_data = SS_NO_SENSE;
1949 /* Check that only command bytes listed in the mask are non-zero */
1950 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1951 for (i = 1; i < cmnd_size; ++i) {
1952 if (common->cmnd[i] && !(mask & (1 << i))) {
1954 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1959 /* If the medium isn't mounted and the command needs to access
1960 * it, return an error. */
1961 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1962 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1969 static int do_scsi_command(struct fsg_common *common)
1971 struct fsg_buffhd *bh;
1973 int reply = -EINVAL;
1975 static char unknown[16];
1979 /* Wait for the next buffer to become available for data or status */
1980 bh = common->next_buffhd_to_fill;
1981 common->next_buffhd_to_drain = bh;
1982 while (bh->state != BUF_STATE_EMPTY) {
1983 rc = sleep_thread(common);
1987 common->phase_error = 0;
1988 common->short_packet_received = 0;
1990 down_read(&common->filesem); /* We're using the backing file */
1991 switch (common->cmnd[0]) {
1994 common->data_size_from_cmnd = common->cmnd[4];
1995 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1999 reply = do_inquiry(common, bh);
2003 common->data_size_from_cmnd = common->cmnd[4];
2004 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
2008 reply = do_mode_select(common, bh);
2011 case MODE_SELECT_10:
2012 common->data_size_from_cmnd =
2013 get_unaligned_be16(&common->cmnd[7]);
2014 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
2018 reply = do_mode_select(common, bh);
2022 common->data_size_from_cmnd = common->cmnd[4];
2023 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2024 (1<<1) | (1<<2) | (1<<4), 0,
2027 reply = do_mode_sense(common, bh);
2031 common->data_size_from_cmnd =
2032 get_unaligned_be16(&common->cmnd[7]);
2033 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2034 (1<<1) | (1<<2) | (3<<7), 0,
2037 reply = do_mode_sense(common, bh);
2040 case ALLOW_MEDIUM_REMOVAL:
2041 common->data_size_from_cmnd = 0;
2042 reply = check_command(common, 6, DATA_DIR_NONE,
2044 "PREVENT-ALLOW MEDIUM REMOVAL");
2046 reply = do_prevent_allow(common);
2050 i = common->cmnd[4];
2051 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
2052 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2056 reply = do_read(common);
2060 common->data_size_from_cmnd =
2061 get_unaligned_be16(&common->cmnd[7]) << 9;
2062 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2063 (1<<1) | (0xf<<2) | (3<<7), 1,
2066 reply = do_read(common);
2070 common->data_size_from_cmnd =
2071 get_unaligned_be32(&common->cmnd[6]) << 9;
2072 reply = check_command(common, 12, DATA_DIR_TO_HOST,
2073 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2076 reply = do_read(common);
2080 common->data_size_from_cmnd = 8;
2081 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2082 (0xf<<2) | (1<<8), 1,
2085 reply = do_read_capacity(common, bh);
2089 if (!common->curlun || !common->curlun->cdrom)
2091 common->data_size_from_cmnd =
2092 get_unaligned_be16(&common->cmnd[7]);
2093 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2094 (3<<7) | (0x1f<<1), 1,
2097 reply = do_read_header(common, bh);
2101 if (!common->curlun || !common->curlun->cdrom)
2103 common->data_size_from_cmnd =
2104 get_unaligned_be16(&common->cmnd[7]);
2105 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2109 reply = do_read_toc(common, bh);
2112 case READ_FORMAT_CAPACITIES:
2113 common->data_size_from_cmnd =
2114 get_unaligned_be16(&common->cmnd[7]);
2115 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2117 "READ FORMAT CAPACITIES");
2119 reply = do_read_format_capacities(common, bh);
2123 common->data_size_from_cmnd = common->cmnd[4];
2124 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2128 reply = do_request_sense(common, bh);
2132 common->data_size_from_cmnd = 0;
2133 reply = check_command(common, 6, DATA_DIR_NONE,
2137 reply = do_start_stop(common);
2140 case SYNCHRONIZE_CACHE:
2141 common->data_size_from_cmnd = 0;
2142 reply = check_command(common, 10, DATA_DIR_NONE,
2143 (0xf<<2) | (3<<7), 1,
2144 "SYNCHRONIZE CACHE");
2146 reply = do_synchronize_cache(common);
2149 case TEST_UNIT_READY:
2150 common->data_size_from_cmnd = 0;
2151 reply = check_command(common, 6, DATA_DIR_NONE,
2157 * Although optional, this command is used by MS-Windows. We
2158 * support a minimal version: BytChk must be 0.
2161 common->data_size_from_cmnd = 0;
2162 reply = check_command(common, 10, DATA_DIR_NONE,
2163 (1<<1) | (0xf<<2) | (3<<7), 1,
2166 reply = do_verify(common);
2170 i = common->cmnd[4];
2171 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
2172 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
2176 reply = do_write(common);
2180 common->data_size_from_cmnd =
2181 get_unaligned_be16(&common->cmnd[7]) << 9;
2182 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
2183 (1<<1) | (0xf<<2) | (3<<7), 1,
2186 reply = do_write(common);
2190 common->data_size_from_cmnd =
2191 get_unaligned_be32(&common->cmnd[6]) << 9;
2192 reply = check_command(common, 12, DATA_DIR_FROM_HOST,
2193 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2196 reply = do_write(common);
2200 * Some mandatory commands that we recognize but don't implement.
2201 * They don't mean much in this setting. It's left as an exercise
2202 * for anyone interested to implement RESERVE and RELEASE in terms
2208 case SEND_DIAGNOSTIC:
2213 common->data_size_from_cmnd = 0;
2214 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2215 reply = check_command(common, common->cmnd_size,
2216 DATA_DIR_UNKNOWN, 0xff, 0, unknown);
2218 common->curlun->sense_data = SS_INVALID_COMMAND;
2223 up_read(&common->filesem);
2225 if (reply == -EINTR || signal_pending(current))
2228 /* Set up the single reply buffer for finish_reply() */
2229 if (reply == -EINVAL)
2230 reply = 0; /* Error reply length */
2231 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2232 reply = min((u32)reply, common->data_size_from_cmnd);
2233 bh->inreq->length = reply;
2234 bh->state = BUF_STATE_FULL;
2235 common->residue -= reply;
2236 } /* Otherwise it's already set */
2242 /*-------------------------------------------------------------------------*/
2244 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2246 struct usb_request *req = bh->outreq;
2247 struct fsg_bulk_cb_wrap *cbw = req->buf;
2248 struct fsg_common *common = fsg->common;
2250 /* Was this a real packet? Should it be ignored? */
2251 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2254 /* Is the CBW valid? */
2255 if (req->actual != USB_BULK_CB_WRAP_LEN ||
2256 cbw->Signature != cpu_to_le32(
2258 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2260 le32_to_cpu(cbw->Signature));
2263 * The Bulk-only spec says we MUST stall the IN endpoint
2264 * (6.6.1), so it's unavoidable. It also says we must
2265 * retain this state until the next reset, but there's
2266 * no way to tell the controller driver it should ignore
2267 * Clear-Feature(HALT) requests.
2269 * We aren't required to halt the OUT endpoint; instead
2270 * we can simply accept and discard any data received
2271 * until the next reset.
2273 wedge_bulk_in_endpoint(fsg);
2274 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2278 /* Is the CBW meaningful? */
2279 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG ||
2280 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2281 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2283 cbw->Lun, cbw->Flags, cbw->Length);
2286 * We can do anything we want here, so let's stall the
2287 * bulk pipes if we are allowed to.
2289 if (common->can_stall) {
2290 fsg_set_halt(fsg, fsg->bulk_out);
2291 halt_bulk_in_endpoint(fsg);
2296 /* Save the command for later */
2297 common->cmnd_size = cbw->Length;
2298 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2299 if (cbw->Flags & USB_BULK_IN_FLAG)
2300 common->data_dir = DATA_DIR_TO_HOST;
2302 common->data_dir = DATA_DIR_FROM_HOST;
2303 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2304 if (common->data_size == 0)
2305 common->data_dir = DATA_DIR_NONE;
2306 common->lun = cbw->Lun;
2307 common->tag = cbw->Tag;
2311 static int get_next_command(struct fsg_common *common)
2313 struct fsg_buffhd *bh;
2316 /* Wait for the next buffer to become available */
2317 bh = common->next_buffhd_to_fill;
2318 while (bh->state != BUF_STATE_EMPTY) {
2319 rc = sleep_thread(common);
2324 /* Queue a request to read a Bulk-only CBW */
2325 set_bulk_out_req_length(common, bh, USB_BULK_CB_WRAP_LEN);
2326 bh->outreq->short_not_ok = 1;
2327 if (!start_out_transfer(common, bh))
2328 /* Don't know what to do if common->fsg is NULL */
2332 * We will drain the buffer in software, which means we
2333 * can reuse it for the next filling. No need to advance
2334 * next_buffhd_to_fill.
2337 /* Wait for the CBW to arrive */
2338 while (bh->state != BUF_STATE_FULL) {
2339 rc = sleep_thread(common);
2344 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2345 bh->state = BUF_STATE_EMPTY;
2351 /*-------------------------------------------------------------------------*/
2353 static int enable_endpoint(struct fsg_common *common, struct usb_ep *ep,
2354 const struct usb_endpoint_descriptor *d)
2358 ep->driver_data = common;
2359 rc = usb_ep_enable(ep, d);
2361 ERROR(common, "can't enable %s, result %d\n", ep->name, rc);
2365 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2366 struct usb_request **preq)
2368 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2371 ERROR(common, "can't allocate request for %s\n", ep->name);
2375 /* Reset interface setting and re-init endpoint state (toggle etc). */
2376 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2378 const struct usb_endpoint_descriptor *d;
2379 struct fsg_dev *fsg;
2382 if (common->running)
2383 DBG(common, "reset interface\n");
2386 /* Deallocate the requests */
2390 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2391 struct fsg_buffhd *bh = &common->buffhds[i];
2394 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2398 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2403 /* Disable the endpoints */
2404 if (fsg->bulk_in_enabled) {
2405 usb_ep_disable(fsg->bulk_in);
2406 fsg->bulk_in_enabled = 0;
2408 if (fsg->bulk_out_enabled) {
2409 usb_ep_disable(fsg->bulk_out);
2410 fsg->bulk_out_enabled = 0;
2414 wake_up(&common->fsg_wait);
2417 common->running = 0;
2421 common->fsg = new_fsg;
2424 /* Enable the endpoints */
2425 d = fsg_ep_desc(common->gadget,
2426 &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
2427 rc = enable_endpoint(common, fsg->bulk_in, d);
2430 fsg->bulk_in_enabled = 1;
2432 d = fsg_ep_desc(common->gadget,
2433 &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
2434 rc = enable_endpoint(common, fsg->bulk_out, d);
2437 fsg->bulk_out_enabled = 1;
2438 common->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
2439 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2441 /* Allocate the requests */
2442 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2443 struct fsg_buffhd *bh = &common->buffhds[i];
2445 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2448 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2451 bh->inreq->buf = bh->outreq->buf = bh->buf;
2452 bh->inreq->context = bh->outreq->context = bh;
2453 bh->inreq->complete = bulk_in_complete;
2454 bh->outreq->complete = bulk_out_complete;
2457 common->running = 1;
2458 for (i = 0; i < common->nluns; ++i)
2459 common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
2464 /****************************** ALT CONFIGS ******************************/
2466 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2468 struct fsg_dev *fsg = fsg_from_func(f);
2469 fsg->common->new_fsg = fsg;
2470 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2474 static void fsg_disable(struct usb_function *f)
2476 struct fsg_dev *fsg = fsg_from_func(f);
2477 fsg->common->new_fsg = NULL;
2478 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2482 /*-------------------------------------------------------------------------*/
2484 static void handle_exception(struct fsg_common *common)
2488 struct fsg_buffhd *bh;
2489 enum fsg_state old_state;
2490 struct fsg_lun *curlun;
2491 unsigned int exception_req_tag;
2494 * Clear the existing signals. Anything but SIGUSR1 is converted
2495 * into a high-priority EXIT exception.
2499 dequeue_signal_lock(current, ¤t->blocked, &info);
2502 if (sig != SIGUSR1) {
2503 if (common->state < FSG_STATE_EXIT)
2504 DBG(common, "Main thread exiting on signal\n");
2505 raise_exception(common, FSG_STATE_EXIT);
2509 /* Cancel all the pending transfers */
2510 if (likely(common->fsg)) {
2511 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2512 bh = &common->buffhds[i];
2514 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2515 if (bh->outreq_busy)
2516 usb_ep_dequeue(common->fsg->bulk_out,
2520 /* Wait until everything is idle */
2523 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2524 bh = &common->buffhds[i];
2525 num_active += bh->inreq_busy + bh->outreq_busy;
2527 if (num_active == 0)
2529 if (sleep_thread(common))
2533 /* Clear out the controller's fifos */
2534 if (common->fsg->bulk_in_enabled)
2535 usb_ep_fifo_flush(common->fsg->bulk_in);
2536 if (common->fsg->bulk_out_enabled)
2537 usb_ep_fifo_flush(common->fsg->bulk_out);
2541 * Reset the I/O buffer states and pointers, the SCSI
2542 * state, and the exception. Then invoke the handler.
2544 spin_lock_irq(&common->lock);
2546 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2547 bh = &common->buffhds[i];
2548 bh->state = BUF_STATE_EMPTY;
2550 common->next_buffhd_to_fill = &common->buffhds[0];
2551 common->next_buffhd_to_drain = &common->buffhds[0];
2552 exception_req_tag = common->exception_req_tag;
2553 old_state = common->state;
2555 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2556 common->state = FSG_STATE_STATUS_PHASE;
2558 for (i = 0; i < common->nluns; ++i) {
2559 curlun = &common->luns[i];
2560 curlun->prevent_medium_removal = 0;
2561 curlun->sense_data = SS_NO_SENSE;
2562 curlun->unit_attention_data = SS_NO_SENSE;
2563 curlun->sense_data_info = 0;
2564 curlun->info_valid = 0;
2566 common->state = FSG_STATE_IDLE;
2568 spin_unlock_irq(&common->lock);
2570 /* Carry out any extra actions required for the exception */
2571 switch (old_state) {
2572 case FSG_STATE_ABORT_BULK_OUT:
2573 send_status(common);
2574 spin_lock_irq(&common->lock);
2575 if (common->state == FSG_STATE_STATUS_PHASE)
2576 common->state = FSG_STATE_IDLE;
2577 spin_unlock_irq(&common->lock);
2580 case FSG_STATE_RESET:
2582 * In case we were forced against our will to halt a
2583 * bulk endpoint, clear the halt now. (The SuperH UDC
2586 if (!fsg_is_set(common))
2588 if (test_and_clear_bit(IGNORE_BULK_OUT,
2589 &common->fsg->atomic_bitflags))
2590 usb_ep_clear_halt(common->fsg->bulk_in);
2592 if (common->ep0_req_tag == exception_req_tag)
2593 ep0_queue(common); /* Complete the status stage */
2596 * Technically this should go here, but it would only be
2597 * a waste of time. Ditto for the INTERFACE_CHANGE and
2598 * CONFIG_CHANGE cases.
2600 /* for (i = 0; i < common->nluns; ++i) */
2601 /* common->luns[i].unit_attention_data = */
2602 /* SS_RESET_OCCURRED; */
2605 case FSG_STATE_CONFIG_CHANGE:
2606 do_set_interface(common, common->new_fsg);
2609 case FSG_STATE_EXIT:
2610 case FSG_STATE_TERMINATED:
2611 do_set_interface(common, NULL); /* Free resources */
2612 spin_lock_irq(&common->lock);
2613 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2614 spin_unlock_irq(&common->lock);
2617 case FSG_STATE_INTERFACE_CHANGE:
2618 case FSG_STATE_DISCONNECT:
2619 case FSG_STATE_COMMAND_PHASE:
2620 case FSG_STATE_DATA_PHASE:
2621 case FSG_STATE_STATUS_PHASE:
2622 case FSG_STATE_IDLE:
2628 /*-------------------------------------------------------------------------*/
2630 static int fsg_main_thread(void *common_)
2632 struct fsg_common *common = common_;
2635 * Allow the thread to be killed by a signal, but set the signal mask
2636 * to block everything but INT, TERM, KILL, and USR1.
2638 allow_signal(SIGINT);
2639 allow_signal(SIGTERM);
2640 allow_signal(SIGKILL);
2641 allow_signal(SIGUSR1);
2643 /* Allow the thread to be frozen */
2647 * Arrange for userspace references to be interpreted as kernel
2648 * pointers. That way we can pass a kernel pointer to a routine
2649 * that expects a __user pointer and it will work okay.
2654 while (common->state != FSG_STATE_TERMINATED) {
2655 if (exception_in_progress(common) || signal_pending(current)) {
2656 handle_exception(common);
2660 if (!common->running) {
2661 sleep_thread(common);
2665 if (get_next_command(common))
2668 spin_lock_irq(&common->lock);
2669 if (!exception_in_progress(common))
2670 common->state = FSG_STATE_DATA_PHASE;
2671 spin_unlock_irq(&common->lock);
2673 if (do_scsi_command(common) || finish_reply(common))
2676 spin_lock_irq(&common->lock);
2677 if (!exception_in_progress(common))
2678 common->state = FSG_STATE_STATUS_PHASE;
2679 spin_unlock_irq(&common->lock);
2681 if (send_status(common))
2684 spin_lock_irq(&common->lock);
2685 if (!exception_in_progress(common))
2686 common->state = FSG_STATE_IDLE;
2687 spin_unlock_irq(&common->lock);
2690 spin_lock_irq(&common->lock);
2691 common->thread_task = NULL;
2692 spin_unlock_irq(&common->lock);
2694 if (!common->ops || !common->ops->thread_exits
2695 || common->ops->thread_exits(common) < 0) {
2696 struct fsg_lun *curlun = common->luns;
2697 unsigned i = common->nluns;
2699 down_write(&common->filesem);
2700 for (; i--; ++curlun) {
2701 if (!fsg_lun_is_open(curlun))
2704 fsg_lun_close(curlun);
2705 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
2707 up_write(&common->filesem);
2710 /* Let fsg_unbind() know the thread has exited */
2711 complete_and_exit(&common->thread_notifier, 0);
2715 /*************************** DEVICE ATTRIBUTES ***************************/
2717 /* Write permission is checked per LUN in store_*() functions. */
2718 static DEVICE_ATTR(ro, 0644, fsg_show_ro, fsg_store_ro);
2719 static DEVICE_ATTR(nofua, 0644, fsg_show_nofua, fsg_store_nofua);
2720 static DEVICE_ATTR(file, 0644, fsg_show_file, fsg_store_file);
2723 /****************************** FSG COMMON ******************************/
2725 static void fsg_common_release(struct kref *ref);
2727 static void fsg_lun_release(struct device *dev)
2729 /* Nothing needs to be done */
2732 static inline void fsg_common_get(struct fsg_common *common)
2734 kref_get(&common->ref);
2737 static inline void fsg_common_put(struct fsg_common *common)
2739 kref_put(&common->ref, fsg_common_release);
2742 static struct fsg_common *fsg_common_init(struct fsg_common *common,
2743 struct usb_composite_dev *cdev,
2744 struct fsg_config *cfg)
2746 struct usb_gadget *gadget = cdev->gadget;
2747 struct fsg_buffhd *bh;
2748 struct fsg_lun *curlun;
2749 struct fsg_lun_config *lcfg;
2753 /* Find out how many LUNs there should be */
2755 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2756 dev_err(&gadget->dev, "invalid number of LUNs: %u\n", nluns);
2757 return ERR_PTR(-EINVAL);
2762 common = kzalloc(sizeof *common, GFP_KERNEL);
2764 return ERR_PTR(-ENOMEM);
2765 common->free_storage_on_release = 1;
2767 memset(common, 0, sizeof *common);
2768 common->free_storage_on_release = 0;
2771 common->ops = cfg->ops;
2772 common->private_data = cfg->private_data;
2774 common->gadget = gadget;
2775 common->ep0 = gadget->ep0;
2776 common->ep0req = cdev->req;
2778 /* Maybe allocate device-global string IDs, and patch descriptors */
2779 if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
2780 rc = usb_string_id(cdev);
2781 if (unlikely(rc < 0))
2783 fsg_strings[FSG_STRING_INTERFACE].id = rc;
2784 fsg_intf_desc.iInterface = rc;
2788 * Create the LUNs, open their backing files, and register the
2789 * LUN devices in sysfs.
2791 curlun = kzalloc(nluns * sizeof *curlun, GFP_KERNEL);
2792 if (unlikely(!curlun)) {
2796 common->luns = curlun;
2798 init_rwsem(&common->filesem);
2800 for (i = 0, lcfg = cfg->luns; i < nluns; ++i, ++curlun, ++lcfg) {
2801 curlun->cdrom = !!lcfg->cdrom;
2802 curlun->ro = lcfg->cdrom || lcfg->ro;
2803 curlun->removable = lcfg->removable;
2804 curlun->dev.release = fsg_lun_release;
2805 curlun->dev.parent = &gadget->dev;
2806 /* curlun->dev.driver = &fsg_driver.driver; XXX */
2807 dev_set_drvdata(&curlun->dev, &common->filesem);
2808 dev_set_name(&curlun->dev,
2809 cfg->lun_name_format
2810 ? cfg->lun_name_format
2814 rc = device_register(&curlun->dev);
2816 INFO(common, "failed to register LUN%d: %d\n", i, rc);
2818 put_device(&curlun->dev);
2822 rc = device_create_file(&curlun->dev, &dev_attr_ro);
2825 rc = device_create_file(&curlun->dev, &dev_attr_file);
2828 rc = device_create_file(&curlun->dev, &dev_attr_nofua);
2832 if (lcfg->filename) {
2833 rc = fsg_lun_open(curlun, lcfg->filename);
2836 } else if (!curlun->removable) {
2837 ERROR(common, "no file given for LUN%d\n", i);
2842 common->nluns = nluns;
2844 /* Data buffers cyclic list */
2845 bh = common->buffhds;
2846 i = FSG_NUM_BUFFERS;
2847 goto buffhds_first_it;
2852 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2853 if (unlikely(!bh->buf)) {
2858 bh->next = common->buffhds;
2860 /* Prepare inquiryString */
2861 if (cfg->release != 0xffff) {
2864 i = usb_gadget_controller_number(gadget);
2868 WARNING(common, "controller '%s' not recognized\n",
2873 snprintf(common->inquiry_string, sizeof common->inquiry_string,
2874 "%-8s%-16s%04x", cfg->vendor_name ?: "Linux",
2875 /* Assume product name dependent on the first LUN */
2876 cfg->product_name ?: (common->luns->cdrom
2877 ? "File-Stor Gadget"
2878 : "File-CD Gadget"),
2882 * Some peripheral controllers are known not to be able to
2883 * halt bulk endpoints correctly. If one of them is present,
2886 common->can_stall = cfg->can_stall &&
2887 !(gadget_is_at91(common->gadget));
2889 spin_lock_init(&common->lock);
2890 kref_init(&common->ref);
2892 /* Tell the thread to start working */
2893 common->thread_task =
2894 kthread_create(fsg_main_thread, common,
2895 cfg->thread_name ?: "file-storage");
2896 if (IS_ERR(common->thread_task)) {
2897 rc = PTR_ERR(common->thread_task);
2900 init_completion(&common->thread_notifier);
2901 init_waitqueue_head(&common->fsg_wait);
2904 INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2905 INFO(common, "Number of LUNs=%d\n", common->nluns);
2907 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2908 for (i = 0, nluns = common->nluns, curlun = common->luns;
2911 char *p = "(no medium)";
2912 if (fsg_lun_is_open(curlun)) {
2915 p = d_path(&curlun->filp->f_path,
2921 LINFO(curlun, "LUN: %s%s%sfile: %s\n",
2922 curlun->removable ? "removable " : "",
2923 curlun->ro ? "read only " : "",
2924 curlun->cdrom ? "CD-ROM " : "",
2929 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
2931 wake_up_process(common->thread_task);
2936 common->nluns = i + 1;
2938 common->state = FSG_STATE_TERMINATED; /* The thread is dead */
2939 /* Call fsg_common_release() directly, ref might be not initialised. */
2940 fsg_common_release(&common->ref);
2944 static void fsg_common_release(struct kref *ref)
2946 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
2948 /* If the thread isn't already dead, tell it to exit now */
2949 if (common->state != FSG_STATE_TERMINATED) {
2950 raise_exception(common, FSG_STATE_EXIT);
2951 wait_for_completion(&common->thread_notifier);
2954 if (likely(common->luns)) {
2955 struct fsg_lun *lun = common->luns;
2956 unsigned i = common->nluns;
2958 /* In error recovery common->nluns may be zero. */
2959 for (; i; --i, ++lun) {
2960 device_remove_file(&lun->dev, &dev_attr_nofua);
2961 device_remove_file(&lun->dev, &dev_attr_ro);
2962 device_remove_file(&lun->dev, &dev_attr_file);
2964 device_unregister(&lun->dev);
2967 kfree(common->luns);
2971 struct fsg_buffhd *bh = common->buffhds;
2972 unsigned i = FSG_NUM_BUFFERS;
2975 } while (++bh, --i);
2978 if (common->free_storage_on_release)
2983 /*-------------------------------------------------------------------------*/
2985 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
2987 struct fsg_dev *fsg = fsg_from_func(f);
2988 struct fsg_common *common = fsg->common;
2990 DBG(fsg, "unbind\n");
2991 if (fsg->common->fsg == fsg) {
2992 fsg->common->new_fsg = NULL;
2993 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2994 /* FIXME: make interruptible or killable somehow? */
2995 wait_event(common->fsg_wait, common->fsg != fsg);
2998 fsg_common_put(common);
2999 usb_free_descriptors(fsg->function.descriptors);
3000 usb_free_descriptors(fsg->function.hs_descriptors);
3004 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
3006 struct fsg_dev *fsg = fsg_from_func(f);
3007 struct usb_gadget *gadget = c->cdev->gadget;
3011 fsg->gadget = gadget;
3014 i = usb_interface_id(c, f);
3017 fsg_intf_desc.bInterfaceNumber = i;
3018 fsg->interface_number = i;
3020 /* Find all the endpoints we will use */
3021 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
3024 ep->driver_data = fsg->common; /* claim the endpoint */
3027 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
3030 ep->driver_data = fsg->common; /* claim the endpoint */
3033 /* Copy descriptors */
3034 f->descriptors = usb_copy_descriptors(fsg_fs_function);
3035 if (unlikely(!f->descriptors))
3038 if (gadget_is_dualspeed(gadget)) {
3039 /* Assume endpoint addresses are the same for both speeds */
3040 fsg_hs_bulk_in_desc.bEndpointAddress =
3041 fsg_fs_bulk_in_desc.bEndpointAddress;
3042 fsg_hs_bulk_out_desc.bEndpointAddress =
3043 fsg_fs_bulk_out_desc.bEndpointAddress;
3044 f->hs_descriptors = usb_copy_descriptors(fsg_hs_function);
3045 if (unlikely(!f->hs_descriptors)) {
3046 usb_free_descriptors(f->descriptors);
3054 ERROR(fsg, "unable to autoconfigure all endpoints\n");
3059 /****************************** ADD FUNCTION ******************************/
3061 static struct usb_gadget_strings *fsg_strings_array[] = {
3066 static int fsg_bind_config(struct usb_composite_dev *cdev,
3067 struct usb_configuration *c,
3068 struct fsg_common *common)
3070 struct fsg_dev *fsg;
3073 fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
3077 fsg->function.name = FSG_DRIVER_DESC;
3078 fsg->function.strings = fsg_strings_array;
3079 fsg->function.bind = fsg_bind;
3080 fsg->function.unbind = fsg_unbind;
3081 fsg->function.setup = fsg_setup;
3082 fsg->function.set_alt = fsg_set_alt;
3083 fsg->function.disable = fsg_disable;
3085 fsg->common = common;
3087 * Our caller holds a reference to common structure so we
3088 * don't have to be worry about it being freed until we return
3089 * from this function. So instead of incrementing counter now
3090 * and decrement in error recovery we increment it only when
3091 * call to usb_add_function() was successful.
3094 rc = usb_add_function(c, &fsg->function);
3098 fsg_common_get(fsg->common);
3102 static inline int __deprecated __maybe_unused
3103 fsg_add(struct usb_composite_dev *cdev, struct usb_configuration *c,
3104 struct fsg_common *common)
3106 return fsg_bind_config(cdev, c, common);
3110 /************************* Module parameters *************************/
3112 struct fsg_module_parameters {
3113 char *file[FSG_MAX_LUNS];
3114 int ro[FSG_MAX_LUNS];
3115 int removable[FSG_MAX_LUNS];
3116 int cdrom[FSG_MAX_LUNS];
3117 int nofua[FSG_MAX_LUNS];
3119 unsigned int file_count, ro_count, removable_count, cdrom_count;
3120 unsigned int nofua_count;
3121 unsigned int luns; /* nluns */
3122 int stall; /* can_stall */
3125 #define _FSG_MODULE_PARAM_ARRAY(prefix, params, name, type, desc) \
3126 module_param_array_named(prefix ## name, params.name, type, \
3127 &prefix ## params.name ## _count, \
3129 MODULE_PARM_DESC(prefix ## name, desc)
3131 #define _FSG_MODULE_PARAM(prefix, params, name, type, desc) \
3132 module_param_named(prefix ## name, params.name, type, \
3134 MODULE_PARM_DESC(prefix ## name, desc)
3136 #define FSG_MODULE_PARAMETERS(prefix, params) \
3137 _FSG_MODULE_PARAM_ARRAY(prefix, params, file, charp, \
3138 "names of backing files or devices"); \
3139 _FSG_MODULE_PARAM_ARRAY(prefix, params, ro, bool, \
3140 "true to force read-only"); \
3141 _FSG_MODULE_PARAM_ARRAY(prefix, params, removable, bool, \
3142 "true to simulate removable media"); \
3143 _FSG_MODULE_PARAM_ARRAY(prefix, params, cdrom, bool, \
3144 "true to simulate CD-ROM instead of disk"); \
3145 _FSG_MODULE_PARAM_ARRAY(prefix, params, nofua, bool, \
3146 "true to ignore SCSI WRITE(10,12) FUA bit"); \
3147 _FSG_MODULE_PARAM(prefix, params, luns, uint, \
3148 "number of LUNs"); \
3149 _FSG_MODULE_PARAM(prefix, params, stall, bool, \
3150 "false to prevent bulk stalls")
3153 fsg_config_from_params(struct fsg_config *cfg,
3154 const struct fsg_module_parameters *params)
3156 struct fsg_lun_config *lun;
3159 /* Configure LUNs */
3161 min(params->luns ?: (params->file_count ?: 1u),
3162 (unsigned)FSG_MAX_LUNS);
3163 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3164 lun->ro = !!params->ro[i];
3165 lun->cdrom = !!params->cdrom[i];
3166 lun->removable = /* Removable by default */
3167 params->removable_count <= i || params->removable[i];
3169 params->file_count > i && params->file[i][0]
3174 /* Let MSF use defaults */
3175 cfg->lun_name_format = 0;
3176 cfg->thread_name = 0;
3177 cfg->vendor_name = 0;
3178 cfg->product_name = 0;
3179 cfg->release = 0xffff;
3182 cfg->private_data = NULL;
3185 cfg->can_stall = params->stall;
3188 static inline struct fsg_common *
3189 fsg_common_from_params(struct fsg_common *common,
3190 struct usb_composite_dev *cdev,
3191 const struct fsg_module_parameters *params)
3192 __attribute__((unused));
3193 static inline struct fsg_common *
3194 fsg_common_from_params(struct fsg_common *common,
3195 struct usb_composite_dev *cdev,
3196 const struct fsg_module_parameters *params)
3198 struct fsg_config cfg;
3199 fsg_config_from_params(&cfg, params);
3200 return fsg_common_init(common, cdev, &cfg);