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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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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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.
42 * The Mass Storage Function acts as a USB Mass Storage device,
43 * appearing to the host as a disk drive or as a CD-ROM drive. In
44 * addition to providing an example of a genuinely useful composite
45 * function for a USB device, it also illustrates a technique of
46 * double-buffering for increased throughput.
48 * Function supports multiple logical units (LUNs). Backing storage
49 * for each LUN is provided by a regular file or a block device.
50 * Access for each LUN can be limited to read-only. Moreover, the
51 * function can indicate that LUN is removable and/or CD-ROM. (The
52 * later implies read-only access.)
54 * MSF is configured by specifying a fsg_config structure. It has the
57 * nluns Number of LUNs function have (anywhere from 1
58 * to FSG_MAX_LUNS which is 8).
59 * luns An array of LUN configuration values. This
60 * should be filled for each LUN that
61 * function will include (ie. for "nluns"
62 * LUNs). Each element of the array has
63 * the following fields:
64 * ->filename The path to the backing file for the LUN.
65 * Required if LUN is not marked as
67 * ->ro Flag specifying access to the LUN shall be
68 * read-only. This is implied if CD-ROM
69 * emulation is enabled as well as when
70 * it was impossible to open "filename"
72 * ->removable Flag specifying that LUN shall be indicated as
74 * ->cdrom Flag specifying that LUN shall be reported as
77 * lun_name_format A printf-like format for names of the LUN
78 * devices. This determines how the
79 * directory in sysfs will be named.
80 * Unless you are using several MSFs in
81 * a single gadget (as opposed to single
82 * MSF in many configurations) you may
83 * leave it as NULL (in which case
84 * "lun%d" will be used). In the format
85 * you can use "%d" to index LUNs for
86 * MSF's with more than one LUN. (Beware
87 * that there is only one integer given
88 * as an argument for the format and
89 * specifying invalid format may cause
90 * unspecified behaviour.)
91 * thread_name Name of the kernel thread process used by the
92 * MSF. You can safely set it to NULL
93 * (in which case default "file-storage"
98 * release Information used as a reply to INQUIRY
99 * request. To use default set to NULL,
100 * NULL, 0xffff respectively. The first
101 * field should be 8 and the second 16
102 * characters or less.
104 * can_stall Set to permit function to halt bulk endpoints.
105 * Disabled on some USB devices known not
106 * to work correctly. You should set it
109 * If "removable" is not set for a LUN then a backing file must be
110 * specified. If it is set, then NULL filename means the LUN's medium
111 * is not loaded (an empty string as "filename" in the fsg_config
112 * structure causes error). The CD-ROM emulation includes a single
113 * data track and no audio tracks; hence there need be only one
114 * backing file per LUN. Note also that the CD-ROM block length is
115 * set to 512 rather than the more common value 2048.
118 * MSF includes support for module parameters. If gadget using it
119 * decides to use it, the following module parameters will be
122 * file=filename[,filename...]
123 * Names of the files or block devices used for
125 * ro=b[,b...] Default false, boolean for read-only access.
127 * Default true, boolean for removable media.
128 * cdrom=b[,b...] Default false, boolean for whether to emulate
130 * luns=N Default N = number of filenames, number of
132 * stall Default determined according to the type of
133 * USB device controller (usually true),
134 * boolean to permit the driver to halt
137 * The module parameters may be prefixed with some string. You need
138 * to consult gadget's documentation or source to verify whether it is
139 * using those module parameters and if it does what are the prefixes
140 * (look for FSG_MODULE_PARAMETERS() macro usage, what's inside it is
144 * Requirements are modest; only a bulk-in and a bulk-out endpoint are
145 * needed. The memory requirement amounts to two 16K buffers, size
146 * configurable by a parameter. Support is included for both
147 * full-speed and high-speed operation.
149 * Note that the driver is slightly non-portable in that it assumes a
150 * single memory/DMA buffer will be useable for bulk-in, bulk-out, and
151 * interrupt-in endpoints. With most device controllers this isn't an
152 * issue, but there may be some with hardware restrictions that prevent
153 * a buffer from being used by more than one endpoint.
156 * The pathnames of the backing files and the ro settings are
157 * available in the attribute files "file" and "ro" in the lun<n> (or
158 * to be more precise in a directory which name comes from
159 * "lun_name_format" option!) subdirectory of the gadget's sysfs
160 * directory. If the "removable" option is set, writing to these
161 * files will simulate ejecting/loading the medium (writing an empty
162 * line means eject) and adjusting a write-enable tab. Changes to the
163 * ro setting are not allowed when the medium is loaded or if CD-ROM
164 * emulation is being used.
167 * This function is heavily based on "File-backed Storage Gadget" by
168 * Alan Stern which in turn is heavily based on "Gadget Zero" by David
169 * Brownell. The driver's SCSI command interface was based on the
170 * "Information technology - Small Computer System Interface - 2"
171 * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
172 * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
173 * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
174 * was based on the "Universal Serial Bus Mass Storage Class UFI
175 * Command Specification" document, Revision 1.0, December 14, 1998,
177 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
184 * The MSF is fairly straightforward. There is a main kernel
185 * thread that handles most of the work. Interrupt routines field
186 * callbacks from the controller driver: bulk- and interrupt-request
187 * completion notifications, endpoint-0 events, and disconnect events.
188 * Completion events are passed to the main thread by wakeup calls. Many
189 * ep0 requests are handled at interrupt time, but SetInterface,
190 * SetConfiguration, and device reset requests are forwarded to the
191 * thread in the form of "exceptions" using SIGUSR1 signals (since they
192 * should interrupt any ongoing file I/O operations).
194 * The thread's main routine implements the standard command/data/status
195 * parts of a SCSI interaction. It and its subroutines are full of tests
196 * for pending signals/exceptions -- all this polling is necessary since
197 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
198 * indication that the driver really wants to be running in userspace.)
199 * An important point is that so long as the thread is alive it keeps an
200 * open reference to the backing file. This will prevent unmounting
201 * the backing file's underlying filesystem and could cause problems
202 * during system shutdown, for example. To prevent such problems, the
203 * thread catches INT, TERM, and KILL signals and converts them into
206 * In normal operation the main thread is started during the gadget's
207 * fsg_bind() callback and stopped during fsg_unbind(). But it can
208 * also exit when it receives a signal, and there's no point leaving
209 * the gadget running when the thread is dead. At of this moment, MSF
210 * provides no way to deregister the gadget when thread dies -- maybe
211 * a callback functions is needed.
213 * To provide maximum throughput, the driver uses a circular pipeline of
214 * buffer heads (struct fsg_buffhd). In principle the pipeline can be
215 * arbitrarily long; in practice the benefits don't justify having more
216 * than 2 stages (i.e., double buffering). But it helps to think of the
217 * pipeline as being a long one. Each buffer head contains a bulk-in and
218 * a bulk-out request pointer (since the buffer can be used for both
219 * output and input -- directions always are given from the host's
220 * point of view) as well as a pointer to the buffer and various state
223 * Use of the pipeline follows a simple protocol. There is a variable
224 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
225 * At any time that buffer head may still be in use from an earlier
226 * request, so each buffer head has a state variable indicating whether
227 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
228 * buffer head to be EMPTY, filling the buffer either by file I/O or by
229 * USB I/O (during which the buffer head is BUSY), and marking the buffer
230 * head FULL when the I/O is complete. Then the buffer will be emptied
231 * (again possibly by USB I/O, during which it is marked BUSY) and
232 * finally marked EMPTY again (possibly by a completion routine).
234 * A module parameter tells the driver to avoid stalling the bulk
235 * endpoints wherever the transport specification allows. This is
236 * necessary for some UDCs like the SuperH, which cannot reliably clear a
237 * halt on a bulk endpoint. However, under certain circumstances the
238 * Bulk-only specification requires a stall. In such cases the driver
239 * will halt the endpoint and set a flag indicating that it should clear
240 * the halt in software during the next device reset. Hopefully this
241 * will permit everything to work correctly. Furthermore, although the
242 * specification allows the bulk-out endpoint to halt when the host sends
243 * too much data, implementing this would cause an unavoidable race.
244 * The driver will always use the "no-stall" approach for OUT transfers.
246 * One subtle point concerns sending status-stage responses for ep0
247 * requests. Some of these requests, such as device reset, can involve
248 * interrupting an ongoing file I/O operation, which might take an
249 * arbitrarily long time. During that delay the host might give up on
250 * the original ep0 request and issue a new one. When that happens the
251 * driver should not notify the host about completion of the original
252 * request, as the host will no longer be waiting for it. So the driver
253 * assigns to each ep0 request a unique tag, and it keeps track of the
254 * tag value of the request associated with a long-running exception
255 * (device-reset, interface-change, or configuration-change). When the
256 * exception handler is finished, the status-stage response is submitted
257 * only if the current ep0 request tag is equal to the exception request
258 * tag. Thus only the most recently received ep0 request will get a
259 * status-stage response.
261 * Warning: This driver source file is too long. It ought to be split up
262 * into a header file plus about 3 separate .c files, to handle the details
263 * of the Gadget, USB Mass Storage, and SCSI protocols.
267 /* #define VERBOSE_DEBUG */
268 /* #define DUMP_MSGS */
271 #include <linux/blkdev.h>
272 #include <linux/completion.h>
273 #include <linux/dcache.h>
274 #include <linux/delay.h>
275 #include <linux/device.h>
276 #include <linux/fcntl.h>
277 #include <linux/file.h>
278 #include <linux/fs.h>
279 #include <linux/kref.h>
280 #include <linux/kthread.h>
281 #include <linux/limits.h>
282 #include <linux/rwsem.h>
283 #include <linux/slab.h>
284 #include <linux/spinlock.h>
285 #include <linux/string.h>
286 #include <linux/freezer.h>
287 #include <linux/utsname.h>
289 #include <linux/usb/ch9.h>
290 #include <linux/usb/gadget.h>
292 #include "gadget_chips.h"
296 /*------------------------------------------------------------------------*/
298 #define FSG_DRIVER_DESC "Mass Storage Function"
299 #define FSG_DRIVER_VERSION "2009/09/11"
301 static const char fsg_string_interface[] = "Mass Storage";
304 #define FSG_NO_INTR_EP 1
305 #define FSG_NO_DEVICE_STRINGS 1
307 #define FSG_NO_INTR_EP 1
309 #include "storage_common.c"
312 /*-------------------------------------------------------------------------*/
317 /* Data shared by all the FSG instances. */
319 struct usb_gadget *gadget;
321 struct fsg_dev *prev_fsg;
323 /* filesem protects: backing files in use */
324 struct rw_semaphore filesem;
326 /* lock protects: state, all the req_busy's */
329 struct usb_ep *ep0; /* Copy of gadget->ep0 */
330 struct usb_request *ep0req; /* Copy of cdev->req */
331 unsigned int ep0_req_tag;
332 const char *ep0req_name;
334 struct fsg_buffhd *next_buffhd_to_fill;
335 struct fsg_buffhd *next_buffhd_to_drain;
336 struct fsg_buffhd buffhds[FSG_NUM_BUFFERS];
339 u8 cmnd[MAX_COMMAND_SIZE];
343 struct fsg_lun *luns;
344 struct fsg_lun *curlun;
346 unsigned int bulk_out_maxpacket;
347 enum fsg_state state; /* For exception handling */
348 unsigned int exception_req_tag;
350 u8 config, new_config;
351 enum data_direction data_dir;
353 u32 data_size_from_cmnd;
358 unsigned int can_stall:1;
359 unsigned int free_storage_on_release:1;
360 unsigned int phase_error:1;
361 unsigned int short_packet_received:1;
362 unsigned int bad_lun_okay:1;
363 unsigned int running:1;
365 int thread_wakeup_needed;
366 struct completion thread_notifier;
367 struct task_struct *thread_task;
369 /* Callback function to call when thread exits. */
370 int (*thread_exits)(struct fsg_common *common);
371 /* Gadget's private data. */
374 /* Vendor (8 chars), product (16 chars), release (4
375 * hexadecimal digits) and NUL byte */
376 char inquiry_string[8 + 16 + 4 + 1];
384 struct fsg_lun_config {
385 const char *filename;
389 } luns[FSG_MAX_LUNS];
391 const char *lun_name_format;
392 const char *thread_name;
394 /* Callback function to call when thread exits. If no
395 * callback is set or it returns value lower then zero MSF
396 * will force eject all LUNs it operates on (including those
397 * marked as non-removable or with prevent_medium_removal flag
399 int (*thread_exits)(struct fsg_common *common);
400 /* Gadget's private data. */
403 const char *vendor_name; /* 8 characters or less */
404 const char *product_name; /* 16 characters or less */
412 struct usb_function function;
413 struct usb_gadget *gadget; /* Copy of cdev->gadget */
414 struct fsg_common *common;
416 u16 interface_number;
418 unsigned int bulk_in_enabled:1;
419 unsigned int bulk_out_enabled:1;
421 unsigned long atomic_bitflags;
422 #define IGNORE_BULK_OUT 0
424 struct usb_ep *bulk_in;
425 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);
438 #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);
447 typedef void (*fsg_routine_t)(struct fsg_dev *);
449 static int exception_in_progress(struct fsg_common *common)
451 return common->state > FSG_STATE_IDLE;
454 /* Make bulk-out requests be divisible by the maxpacket size */
455 static void set_bulk_out_req_length(struct fsg_common *common,
456 struct fsg_buffhd *bh, unsigned int length)
460 bh->bulk_out_intended_length = length;
461 rem = length % common->bulk_out_maxpacket;
463 length += common->bulk_out_maxpacket - rem;
464 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);
498 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. */
505 spin_lock_irqsave(&common->lock, flags);
506 if (common->state <= new_state) {
507 common->exception_req_tag = common->ep0_req_tag;
508 common->state = new_state;
509 if (common->thread_task)
510 send_sig_info(SIGUSR1, SEND_SIG_FORCED,
511 common->thread_task);
513 spin_unlock_irqrestore(&common->lock, flags);
517 /*-------------------------------------------------------------------------*/
519 static int ep0_queue(struct fsg_common *common)
523 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
524 common->ep0->driver_data = common;
525 if (rc != 0 && rc != -ESHUTDOWN) {
526 /* We can't do much more than wait for a reset */
527 WARNING(common, "error in submission: %s --> %d\n",
528 common->ep0->name, rc);
533 /*-------------------------------------------------------------------------*/
535 /* Bulk and interrupt endpoint completion handlers.
536 * These always run in_irq. */
538 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
540 struct fsg_common *common = ep->driver_data;
541 struct fsg_buffhd *bh = req->context;
543 if (req->status || req->actual != req->length)
544 DBG(common, "%s --> %d, %u/%u\n", __func__,
545 req->status, req->actual, req->length);
546 if (req->status == -ECONNRESET) /* Request was cancelled */
547 usb_ep_fifo_flush(ep);
549 /* Hold the lock while we update the request and buffer states */
551 spin_lock(&common->lock);
553 bh->state = BUF_STATE_EMPTY;
554 wakeup_thread(common);
555 spin_unlock(&common->lock);
558 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
560 struct fsg_common *common = ep->driver_data;
561 struct fsg_buffhd *bh = req->context;
563 dump_msg(common, "bulk-out", req->buf, req->actual);
564 if (req->status || req->actual != bh->bulk_out_intended_length)
565 DBG(common, "%s --> %d, %u/%u\n", __func__,
566 req->status, req->actual,
567 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);
581 /*-------------------------------------------------------------------------*/
583 /* Ep0 class-specific handlers. These always run in_irq. */
585 static int fsg_setup(struct usb_function *f,
586 const struct usb_ctrlrequest *ctrl)
588 struct fsg_dev *fsg = fsg_from_func(f);
589 struct usb_request *req = fsg->common->ep0req;
590 u16 w_index = le16_to_cpu(ctrl->wIndex);
591 u16 w_value = le16_to_cpu(ctrl->wValue);
592 u16 w_length = le16_to_cpu(ctrl->wLength);
594 if (!fsg->common->config)
597 switch (ctrl->bRequest) {
599 case USB_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)
606 /* Raise an exception to stop the current operation
607 * and reinitialize our state. */
608 DBG(fsg, "bulk reset request\n");
609 raise_exception(fsg->common, FSG_STATE_RESET);
610 return DELAYED_STATUS;
612 case USB_BULK_GET_MAX_LUN_REQUEST:
613 if (ctrl->bRequestType !=
614 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
616 if (w_index != fsg->interface_number || w_value != 0)
618 VDBG(fsg, "get max LUN\n");
619 *(u8 *) req->buf = fsg->common->nluns - 1;
621 /* Respond with data/status */
622 req->length = min((u16)1, w_length);
623 fsg->common->ep0req_name =
624 ctrl->bRequestType & USB_DIR_IN ? "ep0-in" : "ep0-out";
625 return ep0_queue(fsg->common);
629 "unknown class-specific control req "
630 "%02x.%02x v%04x i%04x l%u\n",
631 ctrl->bRequestType, ctrl->bRequest,
632 le16_to_cpu(ctrl->wValue), w_index, w_length);
637 /*-------------------------------------------------------------------------*/
639 /* 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 */
663 /* Note: currently the net2280 driver fails zero-length
664 * submissions if DMA is enabled. */
665 if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP &&
667 WARNING(fsg, "error in submission: %s --> %d\n",
672 #define START_TRANSFER_OR(common, ep_name, req, pbusy, state) \
673 if (fsg_is_set(common)) \
674 start_transfer((common)->fsg, (common)->fsg->ep_name, \
675 req, pbusy, state); \
678 #define START_TRANSFER(common, ep_name, req, pbusy, state) \
679 START_TRANSFER_OR(common, ep_name, req, pbusy, state) (void)0
683 static int sleep_thread(struct fsg_common *common)
687 /* Wait until a signal arrives or we are woken up */
690 set_current_state(TASK_INTERRUPTIBLE);
691 if (signal_pending(current)) {
695 if (common->thread_wakeup_needed)
699 __set_current_state(TASK_RUNNING);
700 common->thread_wakeup_needed = 0;
705 /*-------------------------------------------------------------------------*/
707 static int do_read(struct fsg_common *common)
709 struct fsg_lun *curlun = common->curlun;
711 struct fsg_buffhd *bh;
714 loff_t file_offset, file_offset_tmp;
716 unsigned int partial_page;
719 /* Get the starting Logical Block Address and check that it's
721 if (common->cmnd[0] == SC_READ_6)
722 lba = get_unaligned_be24(&common->cmnd[1]);
724 lba = get_unaligned_be32(&common->cmnd[2]);
726 /* We allow DPO (Disable Page Out = don't save data in the
727 * cache) and FUA (Force Unit Access = don't read from the
728 * cache), but we don't implement them. */
729 if ((common->cmnd[1] & ~0x18) != 0) {
730 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
734 if (lba >= curlun->num_sectors) {
735 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
738 file_offset = ((loff_t) lba) << 9;
740 /* Carry out the file reads */
741 amount_left = common->data_size_from_cmnd;
742 if (unlikely(amount_left == 0))
743 return -EIO; /* No default reply */
747 /* Figure out how much we need to read:
748 * Try to read the remaining amount.
749 * But don't read more than the buffer size.
750 * And don't try to read past the end of the file.
751 * Finally, if we're not at a page boundary, don't read past
753 * If this means reading 0 then we were asked to read past
754 * the end of file. */
755 amount = min(amount_left, FSG_BUFLEN);
756 amount = min((loff_t) amount,
757 curlun->file_length - file_offset);
758 partial_page = file_offset & (PAGE_CACHE_SIZE - 1);
759 if (partial_page > 0)
760 amount = min(amount, (unsigned int) PAGE_CACHE_SIZE -
763 /* Wait for the next buffer to become available */
764 bh = common->next_buffhd_to_fill;
765 while (bh->state != BUF_STATE_EMPTY) {
766 rc = sleep_thread(common);
771 /* If we were asked to read past the end of file,
772 * end with an empty buffer. */
775 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
776 curlun->sense_data_info = file_offset >> 9;
777 curlun->info_valid = 1;
778 bh->inreq->length = 0;
779 bh->state = BUF_STATE_FULL;
783 /* Perform the read */
784 file_offset_tmp = file_offset;
785 nread = vfs_read(curlun->filp,
786 (char __user *) bh->buf,
787 amount, &file_offset_tmp);
788 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
789 (unsigned long long) file_offset,
791 if (signal_pending(current))
795 LDBG(curlun, "error in file read: %d\n",
798 } else if (nread < amount) {
799 LDBG(curlun, "partial file read: %d/%u\n",
800 (int) nread, amount);
801 nread -= (nread & 511); /* Round down to a block */
803 file_offset += nread;
804 amount_left -= nread;
805 common->residue -= nread;
806 bh->inreq->length = nread;
807 bh->state = BUF_STATE_FULL;
809 /* If an error occurred, report it and its position */
810 if (nread < amount) {
811 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
812 curlun->sense_data_info = file_offset >> 9;
813 curlun->info_valid = 1;
817 if (amount_left == 0)
818 break; /* No more left to read */
820 /* Send this buffer and go read some more */
822 START_TRANSFER_OR(common, bulk_in, bh->inreq,
823 &bh->inreq_busy, &bh->state)
824 /* Don't know what to do if
825 * common->fsg is NULL */
827 common->next_buffhd_to_fill = bh->next;
830 return -EIO; /* No default reply */
834 /*-------------------------------------------------------------------------*/
836 static int do_write(struct fsg_common *common)
838 struct fsg_lun *curlun = common->curlun;
840 struct fsg_buffhd *bh;
842 u32 amount_left_to_req, amount_left_to_write;
843 loff_t usb_offset, file_offset, file_offset_tmp;
845 unsigned int partial_page;
850 curlun->sense_data = SS_WRITE_PROTECTED;
853 spin_lock(&curlun->filp->f_lock);
854 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
855 spin_unlock(&curlun->filp->f_lock);
857 /* Get the starting Logical Block Address and check that it's
859 if (common->cmnd[0] == SC_WRITE_6)
860 lba = get_unaligned_be24(&common->cmnd[1]);
862 lba = get_unaligned_be32(&common->cmnd[2]);
864 /* We allow DPO (Disable Page Out = don't save data in the
865 * cache) and FUA (Force Unit Access = write directly to the
866 * medium). We don't implement DPO; we implement FUA by
867 * performing synchronous output. */
868 if (common->cmnd[1] & ~0x18) {
869 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
872 if (common->cmnd[1] & 0x08) { /* FUA */
873 spin_lock(&curlun->filp->f_lock);
874 curlun->filp->f_flags |= O_SYNC;
875 spin_unlock(&curlun->filp->f_lock);
878 if (lba >= curlun->num_sectors) {
879 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
883 /* Carry out the file writes */
885 file_offset = usb_offset = ((loff_t) lba) << 9;
886 amount_left_to_req = common->data_size_from_cmnd;
887 amount_left_to_write = common->data_size_from_cmnd;
889 while (amount_left_to_write > 0) {
891 /* Queue a request for more data from the host */
892 bh = common->next_buffhd_to_fill;
893 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
895 /* Figure out how much we want to get:
896 * Try to get the remaining amount.
897 * But don't get more than the buffer size.
898 * And don't try to go past the end of the file.
899 * If we're not at a page boundary,
900 * don't go past the next page.
901 * If this means getting 0, then we were asked
902 * to write past the end of file.
903 * Finally, round down to a block boundary. */
904 amount = min(amount_left_to_req, FSG_BUFLEN);
905 amount = min((loff_t) amount, curlun->file_length -
907 partial_page = usb_offset & (PAGE_CACHE_SIZE - 1);
908 if (partial_page > 0)
910 (unsigned int) PAGE_CACHE_SIZE - partial_page);
915 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
916 curlun->sense_data_info = usb_offset >> 9;
917 curlun->info_valid = 1;
920 amount -= (amount & 511);
923 /* Why were we were asked to transfer a
929 /* Get the next buffer */
930 usb_offset += amount;
931 common->usb_amount_left -= amount;
932 amount_left_to_req -= amount;
933 if (amount_left_to_req == 0)
936 /* amount is always divisible by 512, hence by
937 * the bulk-out maxpacket size */
938 bh->outreq->length = amount;
939 bh->bulk_out_intended_length = amount;
940 bh->outreq->short_not_ok = 1;
941 START_TRANSFER_OR(common, bulk_out, bh->outreq,
942 &bh->outreq_busy, &bh->state)
943 /* Don't know what to do if
944 * common->fsg is NULL */
946 common->next_buffhd_to_fill = bh->next;
950 /* Write the received data to the backing file */
951 bh = common->next_buffhd_to_drain;
952 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
953 break; /* We stopped early */
954 if (bh->state == BUF_STATE_FULL) {
956 common->next_buffhd_to_drain = bh->next;
957 bh->state = BUF_STATE_EMPTY;
959 /* Did something go wrong with the transfer? */
960 if (bh->outreq->status != 0) {
961 curlun->sense_data = SS_COMMUNICATION_FAILURE;
962 curlun->sense_data_info = file_offset >> 9;
963 curlun->info_valid = 1;
967 amount = bh->outreq->actual;
968 if (curlun->file_length - file_offset < amount) {
970 "write %u @ %llu beyond end %llu\n",
971 amount, (unsigned long long) file_offset,
972 (unsigned long long) curlun->file_length);
973 amount = curlun->file_length - file_offset;
976 /* Perform the write */
977 file_offset_tmp = file_offset;
978 nwritten = vfs_write(curlun->filp,
979 (char __user *) bh->buf,
980 amount, &file_offset_tmp);
981 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
982 (unsigned long long) file_offset,
984 if (signal_pending(current))
985 return -EINTR; /* Interrupted! */
988 LDBG(curlun, "error in file write: %d\n",
991 } else if (nwritten < amount) {
992 LDBG(curlun, "partial file write: %d/%u\n",
993 (int) nwritten, amount);
994 nwritten -= (nwritten & 511);
995 /* Round down to a block */
997 file_offset += nwritten;
998 amount_left_to_write -= nwritten;
999 common->residue -= nwritten;
1001 /* If an error occurred, report it and its position */
1002 if (nwritten < amount) {
1003 curlun->sense_data = SS_WRITE_ERROR;
1004 curlun->sense_data_info = file_offset >> 9;
1005 curlun->info_valid = 1;
1009 /* Did the host decide to stop early? */
1010 if (bh->outreq->actual != bh->outreq->length) {
1011 common->short_packet_received = 1;
1017 /* Wait for something to happen */
1018 rc = sleep_thread(common);
1023 return -EIO; /* No default reply */
1027 /*-------------------------------------------------------------------------*/
1029 static int do_synchronize_cache(struct fsg_common *common)
1031 struct fsg_lun *curlun = common->curlun;
1034 /* We ignore the requested LBA and write out all file's
1035 * dirty data buffers. */
1036 rc = fsg_lun_fsync_sub(curlun);
1038 curlun->sense_data = SS_WRITE_ERROR;
1043 /*-------------------------------------------------------------------------*/
1045 static void invalidate_sub(struct fsg_lun *curlun)
1047 struct file *filp = curlun->filp;
1048 struct inode *inode = filp->f_path.dentry->d_inode;
1051 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
1052 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
1055 static int do_verify(struct fsg_common *common)
1057 struct fsg_lun *curlun = common->curlun;
1059 u32 verification_length;
1060 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1061 loff_t file_offset, file_offset_tmp;
1063 unsigned int amount;
1066 /* Get the starting Logical Block Address and check that it's
1068 lba = get_unaligned_be32(&common->cmnd[2]);
1069 if (lba >= curlun->num_sectors) {
1070 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1074 /* We allow DPO (Disable Page Out = don't save data in the
1075 * cache) but we don't implement it. */
1076 if (common->cmnd[1] & ~0x10) {
1077 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1081 verification_length = get_unaligned_be16(&common->cmnd[7]);
1082 if (unlikely(verification_length == 0))
1083 return -EIO; /* No default reply */
1085 /* Prepare to carry out the file verify */
1086 amount_left = verification_length << 9;
1087 file_offset = ((loff_t) lba) << 9;
1089 /* Write out all the dirty buffers before invalidating them */
1090 fsg_lun_fsync_sub(curlun);
1091 if (signal_pending(current))
1094 invalidate_sub(curlun);
1095 if (signal_pending(current))
1098 /* Just try to read the requested blocks */
1099 while (amount_left > 0) {
1101 /* Figure out how much we need to read:
1102 * Try to read the remaining amount, but not more than
1104 * And don't try to read past the end of the file.
1105 * If this means reading 0 then we were asked to read
1106 * past the end of file. */
1107 amount = min(amount_left, FSG_BUFLEN);
1108 amount = min((loff_t) amount,
1109 curlun->file_length - file_offset);
1111 curlun->sense_data =
1112 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1113 curlun->sense_data_info = file_offset >> 9;
1114 curlun->info_valid = 1;
1118 /* Perform the read */
1119 file_offset_tmp = file_offset;
1120 nread = vfs_read(curlun->filp,
1121 (char __user *) bh->buf,
1122 amount, &file_offset_tmp);
1123 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1124 (unsigned long long) file_offset,
1126 if (signal_pending(current))
1130 LDBG(curlun, "error in file verify: %d\n",
1133 } else if (nread < amount) {
1134 LDBG(curlun, "partial file verify: %d/%u\n",
1135 (int) nread, amount);
1136 nread -= (nread & 511); /* Round down to a sector */
1139 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1140 curlun->sense_data_info = file_offset >> 9;
1141 curlun->info_valid = 1;
1144 file_offset += nread;
1145 amount_left -= nread;
1151 /*-------------------------------------------------------------------------*/
1153 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1155 struct fsg_lun *curlun = common->curlun;
1156 u8 *buf = (u8 *) bh->buf;
1158 if (!curlun) { /* Unsupported LUNs are okay */
1159 common->bad_lun_okay = 1;
1161 buf[0] = 0x7f; /* Unsupported, no device-type */
1162 buf[4] = 31; /* Additional length */
1166 buf[0] = curlun->cdrom ? TYPE_CDROM : TYPE_DISK;
1167 buf[1] = curlun->removable ? 0x80 : 0;
1168 buf[2] = 2; /* ANSI SCSI level 2 */
1169 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1170 buf[4] = 31; /* Additional length */
1171 buf[5] = 0; /* No special options */
1174 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1179 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1181 struct fsg_lun *curlun = common->curlun;
1182 u8 *buf = (u8 *) bh->buf;
1187 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1189 * If a REQUEST SENSE command is received from an initiator
1190 * with a pending unit attention condition (before the target
1191 * generates the contingent allegiance condition), then the
1192 * target shall either:
1193 * a) report any pending sense data and preserve the unit
1194 * attention condition on the logical unit, or,
1195 * b) report the unit attention condition, may discard any
1196 * pending sense data, and clear the unit attention
1197 * condition on the logical unit for that initiator.
1199 * FSG normally uses option a); enable this code to use option b).
1202 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1203 curlun->sense_data = curlun->unit_attention_data;
1204 curlun->unit_attention_data = SS_NO_SENSE;
1208 if (!curlun) { /* Unsupported LUNs are okay */
1209 common->bad_lun_okay = 1;
1210 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1214 sd = curlun->sense_data;
1215 sdinfo = curlun->sense_data_info;
1216 valid = curlun->info_valid << 7;
1217 curlun->sense_data = SS_NO_SENSE;
1218 curlun->sense_data_info = 0;
1219 curlun->info_valid = 0;
1223 buf[0] = valid | 0x70; /* Valid, current error */
1225 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1226 buf[7] = 18 - 8; /* Additional sense length */
1233 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1235 struct fsg_lun *curlun = common->curlun;
1236 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1237 int pmi = common->cmnd[8];
1238 u8 *buf = (u8 *) bh->buf;
1240 /* Check the PMI and LBA fields */
1241 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1242 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1246 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1247 /* Max logical block */
1248 put_unaligned_be32(512, &buf[4]); /* Block length */
1253 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1255 struct fsg_lun *curlun = common->curlun;
1256 int msf = common->cmnd[1] & 0x02;
1257 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1258 u8 *buf = (u8 *) bh->buf;
1260 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1261 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1264 if (lba >= curlun->num_sectors) {
1265 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1270 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1271 store_cdrom_address(&buf[4], msf, lba);
1276 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1278 struct fsg_lun *curlun = common->curlun;
1279 int msf = common->cmnd[1] & 0x02;
1280 int start_track = common->cmnd[6];
1281 u8 *buf = (u8 *) bh->buf;
1283 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1285 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1290 buf[1] = (20-2); /* TOC data length */
1291 buf[2] = 1; /* First track number */
1292 buf[3] = 1; /* Last track number */
1293 buf[5] = 0x16; /* Data track, copying allowed */
1294 buf[6] = 0x01; /* Only track is number 1 */
1295 store_cdrom_address(&buf[8], msf, 0);
1297 buf[13] = 0x16; /* Lead-out track is data */
1298 buf[14] = 0xAA; /* Lead-out track number */
1299 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1304 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1306 struct fsg_lun *curlun = common->curlun;
1307 int mscmnd = common->cmnd[0];
1308 u8 *buf = (u8 *) bh->buf;
1311 int changeable_values, all_pages;
1315 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1316 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1319 pc = common->cmnd[2] >> 6;
1320 page_code = common->cmnd[2] & 0x3f;
1322 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1325 changeable_values = (pc == 1);
1326 all_pages = (page_code == 0x3f);
1328 /* Write the mode parameter header. Fixed values are: default
1329 * medium type, no cache control (DPOFUA), and no block descriptors.
1330 * The only variable value is the WriteProtect bit. We will fill in
1331 * the mode data length later. */
1333 if (mscmnd == SC_MODE_SENSE_6) {
1334 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1337 } else { /* SC_MODE_SENSE_10 */
1338 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1340 limit = 65535; /* Should really be FSG_BUFLEN */
1343 /* No block descriptors */
1345 /* The mode pages, in numerical order. The only page we support
1346 * is the Caching page. */
1347 if (page_code == 0x08 || all_pages) {
1349 buf[0] = 0x08; /* Page code */
1350 buf[1] = 10; /* Page length */
1351 memset(buf+2, 0, 10); /* None of the fields are changeable */
1353 if (!changeable_values) {
1354 buf[2] = 0x04; /* Write cache enable, */
1355 /* Read cache not disabled */
1356 /* No cache retention priorities */
1357 put_unaligned_be16(0xffff, &buf[4]);
1358 /* Don't disable prefetch */
1359 /* Minimum prefetch = 0 */
1360 put_unaligned_be16(0xffff, &buf[8]);
1361 /* Maximum prefetch */
1362 put_unaligned_be16(0xffff, &buf[10]);
1363 /* Maximum prefetch ceiling */
1368 /* Check that a valid page was requested and the mode data length
1369 * isn't too long. */
1371 if (!valid_page || len > limit) {
1372 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1376 /* Store the mode data length */
1377 if (mscmnd == SC_MODE_SENSE_6)
1380 put_unaligned_be16(len - 2, buf0);
1385 static int do_start_stop(struct fsg_common *common)
1387 if (!common->curlun) {
1389 } else if (!common->curlun->removable) {
1390 common->curlun->sense_data = SS_INVALID_COMMAND;
1397 static int do_prevent_allow(struct fsg_common *common)
1399 struct fsg_lun *curlun = common->curlun;
1402 if (!common->curlun) {
1404 } else if (!common->curlun->removable) {
1405 common->curlun->sense_data = SS_INVALID_COMMAND;
1409 prevent = common->cmnd[4] & 0x01;
1410 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1411 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1415 if (curlun->prevent_medium_removal && !prevent)
1416 fsg_lun_fsync_sub(curlun);
1417 curlun->prevent_medium_removal = prevent;
1422 static int do_read_format_capacities(struct fsg_common *common,
1423 struct fsg_buffhd *bh)
1425 struct fsg_lun *curlun = common->curlun;
1426 u8 *buf = (u8 *) bh->buf;
1428 buf[0] = buf[1] = buf[2] = 0;
1429 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1432 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1433 /* Number of blocks */
1434 put_unaligned_be32(512, &buf[4]); /* Block length */
1435 buf[4] = 0x02; /* Current capacity */
1440 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1442 struct fsg_lun *curlun = common->curlun;
1444 /* We don't support MODE SELECT */
1446 curlun->sense_data = SS_INVALID_COMMAND;
1451 /*-------------------------------------------------------------------------*/
1453 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1457 rc = fsg_set_halt(fsg, fsg->bulk_in);
1459 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1461 if (rc != -EAGAIN) {
1462 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1467 /* Wait for a short time and then try again */
1468 if (msleep_interruptible(100) != 0)
1470 rc = usb_ep_set_halt(fsg->bulk_in);
1475 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1479 DBG(fsg, "bulk-in set wedge\n");
1480 rc = usb_ep_set_wedge(fsg->bulk_in);
1482 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1484 if (rc != -EAGAIN) {
1485 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1490 /* Wait for a short time and then try again */
1491 if (msleep_interruptible(100) != 0)
1493 rc = usb_ep_set_wedge(fsg->bulk_in);
1498 static int pad_with_zeros(struct fsg_dev *fsg)
1500 struct fsg_buffhd *bh = fsg->common->next_buffhd_to_fill;
1501 u32 nkeep = bh->inreq->length;
1505 bh->state = BUF_STATE_EMPTY; /* For the first iteration */
1506 fsg->common->usb_amount_left = nkeep + fsg->common->residue;
1507 while (fsg->common->usb_amount_left > 0) {
1509 /* Wait for the next buffer to be free */
1510 while (bh->state != BUF_STATE_EMPTY) {
1511 rc = sleep_thread(fsg->common);
1516 nsend = min(fsg->common->usb_amount_left, FSG_BUFLEN);
1517 memset(bh->buf + nkeep, 0, nsend - nkeep);
1518 bh->inreq->length = nsend;
1519 bh->inreq->zero = 0;
1520 start_transfer(fsg, fsg->bulk_in, bh->inreq,
1521 &bh->inreq_busy, &bh->state);
1522 bh = fsg->common->next_buffhd_to_fill = bh->next;
1523 fsg->common->usb_amount_left -= nsend;
1529 static int throw_away_data(struct fsg_common *common)
1531 struct fsg_buffhd *bh;
1535 for (bh = common->next_buffhd_to_drain;
1536 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1537 bh = common->next_buffhd_to_drain) {
1539 /* Throw away the data in a filled buffer */
1540 if (bh->state == BUF_STATE_FULL) {
1542 bh->state = BUF_STATE_EMPTY;
1543 common->next_buffhd_to_drain = bh->next;
1545 /* A short packet or an error ends everything */
1546 if (bh->outreq->actual != bh->outreq->length ||
1547 bh->outreq->status != 0) {
1548 raise_exception(common,
1549 FSG_STATE_ABORT_BULK_OUT);
1555 /* Try to submit another request if we need one */
1556 bh = common->next_buffhd_to_fill;
1557 if (bh->state == BUF_STATE_EMPTY
1558 && common->usb_amount_left > 0) {
1559 amount = min(common->usb_amount_left, FSG_BUFLEN);
1561 /* amount is always divisible by 512, hence by
1562 * the bulk-out maxpacket size */
1563 bh->outreq->length = amount;
1564 bh->bulk_out_intended_length = amount;
1565 bh->outreq->short_not_ok = 1;
1566 START_TRANSFER_OR(common, bulk_out, bh->outreq,
1567 &bh->outreq_busy, &bh->state)
1568 /* Don't know what to do if
1569 * common->fsg is NULL */
1571 common->next_buffhd_to_fill = bh->next;
1572 common->usb_amount_left -= amount;
1576 /* Otherwise wait for something to happen */
1577 rc = sleep_thread(common);
1585 static int finish_reply(struct fsg_common *common)
1587 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1590 switch (common->data_dir) {
1592 break; /* Nothing to send */
1594 /* If we don't know whether the host wants to read or write,
1595 * this must be CB or CBI with an unknown command. We mustn't
1596 * try to send or receive any data. So stall both bulk pipes
1597 * if we can and wait for a reset. */
1598 case DATA_DIR_UNKNOWN:
1599 if (!common->can_stall) {
1601 } else if (fsg_is_set(common)) {
1602 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1603 rc = halt_bulk_in_endpoint(common->fsg);
1605 /* Don't know what to do if common->fsg is NULL */
1610 /* All but the last buffer of data must have already been sent */
1611 case DATA_DIR_TO_HOST:
1612 if (common->data_size == 0) {
1613 /* Nothing to send */
1615 /* If there's no residue, simply send the last buffer */
1616 } else if (common->residue == 0) {
1617 bh->inreq->zero = 0;
1618 START_TRANSFER_OR(common, bulk_in, bh->inreq,
1619 &bh->inreq_busy, &bh->state)
1621 common->next_buffhd_to_fill = bh->next;
1623 /* For Bulk-only, if we're allowed to stall then send the
1624 * short packet and halt the bulk-in endpoint. If we can't
1625 * stall, pad out the remaining data with 0's. */
1626 } else if (common->can_stall) {
1627 bh->inreq->zero = 1;
1628 START_TRANSFER_OR(common, bulk_in, bh->inreq,
1629 &bh->inreq_busy, &bh->state)
1630 /* Don't know what to do if
1631 * common->fsg is NULL */
1633 common->next_buffhd_to_fill = bh->next;
1635 rc = halt_bulk_in_endpoint(common->fsg);
1636 } else if (fsg_is_set(common)) {
1637 rc = pad_with_zeros(common->fsg);
1639 /* Don't know what to do if common->fsg is NULL */
1644 /* We have processed all we want from the data the host has sent.
1645 * There may still be outstanding bulk-out requests. */
1646 case DATA_DIR_FROM_HOST:
1647 if (common->residue == 0) {
1648 /* Nothing to receive */
1650 /* Did the host stop sending unexpectedly early? */
1651 } else if (common->short_packet_received) {
1652 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1655 /* We haven't processed all the incoming data. Even though
1656 * we may be allowed to stall, doing so would cause a race.
1657 * The controller may already have ACK'ed all the remaining
1658 * bulk-out packets, in which case the host wouldn't see a
1659 * STALL. Not realizing the endpoint was halted, it wouldn't
1660 * clear the halt -- leading to problems later on. */
1662 } else if (common->can_stall) {
1663 if (fsg_is_set(common))
1664 fsg_set_halt(common->fsg,
1665 common->fsg->bulk_out);
1666 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1670 /* We can't stall. Read in the excess data and throw it
1673 rc = throw_away_data(common);
1681 static int send_status(struct fsg_common *common)
1683 struct fsg_lun *curlun = common->curlun;
1684 struct fsg_buffhd *bh;
1685 struct bulk_cs_wrap *csw;
1687 u8 status = USB_STATUS_PASS;
1690 /* Wait for the next buffer to become available */
1691 bh = common->next_buffhd_to_fill;
1692 while (bh->state != BUF_STATE_EMPTY) {
1693 rc = sleep_thread(common);
1699 sd = curlun->sense_data;
1700 sdinfo = curlun->sense_data_info;
1701 } else if (common->bad_lun_okay)
1704 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1706 if (common->phase_error) {
1707 DBG(common, "sending phase-error status\n");
1708 status = USB_STATUS_PHASE_ERROR;
1709 sd = SS_INVALID_COMMAND;
1710 } else if (sd != SS_NO_SENSE) {
1711 DBG(common, "sending command-failure status\n");
1712 status = USB_STATUS_FAIL;
1713 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1715 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1718 /* Store and send the Bulk-only CSW */
1719 csw = (void *)bh->buf;
1721 csw->Signature = cpu_to_le32(USB_BULK_CS_SIG);
1722 csw->Tag = common->tag;
1723 csw->Residue = cpu_to_le32(common->residue);
1724 csw->Status = status;
1726 bh->inreq->length = USB_BULK_CS_WRAP_LEN;
1727 bh->inreq->zero = 0;
1728 START_TRANSFER_OR(common, bulk_in, bh->inreq,
1729 &bh->inreq_busy, &bh->state)
1730 /* Don't know what to do if common->fsg is NULL */
1733 common->next_buffhd_to_fill = bh->next;
1738 /*-------------------------------------------------------------------------*/
1740 /* Check whether the command is properly formed and whether its data size
1741 * and direction agree with the values we already have. */
1742 static int check_command(struct fsg_common *common, int cmnd_size,
1743 enum data_direction data_dir, unsigned int mask,
1744 int needs_medium, const char *name)
1747 int lun = common->cmnd[1] >> 5;
1748 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1750 struct fsg_lun *curlun;
1753 if (common->data_dir != DATA_DIR_UNKNOWN)
1754 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1756 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1757 name, cmnd_size, dirletter[(int) data_dir],
1758 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1760 /* We can't reply at all until we know the correct data direction
1762 if (common->data_size_from_cmnd == 0)
1763 data_dir = DATA_DIR_NONE;
1764 if (common->data_size < common->data_size_from_cmnd) {
1765 /* Host data size < Device data size is a phase error.
1766 * Carry out the command, but only transfer as much as
1767 * we are allowed. */
1768 common->data_size_from_cmnd = common->data_size;
1769 common->phase_error = 1;
1771 common->residue = common->data_size;
1772 common->usb_amount_left = common->data_size;
1774 /* Conflicting data directions is a phase error */
1775 if (common->data_dir != data_dir
1776 && common->data_size_from_cmnd > 0) {
1777 common->phase_error = 1;
1781 /* Verify the length of the command itself */
1782 if (cmnd_size != common->cmnd_size) {
1784 /* Special case workaround: There are plenty of buggy SCSI
1785 * implementations. Many have issues with cbw->Length
1786 * field passing a wrong command size. For those cases we
1787 * always try to work around the problem by using the length
1788 * sent by the host side provided it is at least as large
1789 * as the correct command length.
1790 * Examples of such cases would be MS-Windows, which issues
1791 * REQUEST SENSE with cbw->Length == 12 where it should
1792 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1793 * REQUEST SENSE with cbw->Length == 10 where it should
1796 if (cmnd_size <= common->cmnd_size) {
1797 DBG(common, "%s is buggy! Expected length %d "
1798 "but we got %d\n", name,
1799 cmnd_size, common->cmnd_size);
1800 cmnd_size = common->cmnd_size;
1802 common->phase_error = 1;
1807 /* Check that the LUN values are consistent */
1808 if (common->lun != lun)
1809 DBG(common, "using LUN %d from CBW, not LUN %d from CDB\n",
1813 if (common->lun >= 0 && common->lun < common->nluns) {
1814 curlun = &common->luns[common->lun];
1815 common->curlun = curlun;
1816 if (common->cmnd[0] != SC_REQUEST_SENSE) {
1817 curlun->sense_data = SS_NO_SENSE;
1818 curlun->sense_data_info = 0;
1819 curlun->info_valid = 0;
1822 common->curlun = NULL;
1824 common->bad_lun_okay = 0;
1826 /* INQUIRY and REQUEST SENSE commands are explicitly allowed
1827 * to use unsupported LUNs; all others may not. */
1828 if (common->cmnd[0] != SC_INQUIRY &&
1829 common->cmnd[0] != SC_REQUEST_SENSE) {
1830 DBG(common, "unsupported LUN %d\n", common->lun);
1835 /* If a unit attention condition exists, only INQUIRY and
1836 * REQUEST SENSE commands are allowed; anything else must fail. */
1837 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1838 common->cmnd[0] != SC_INQUIRY &&
1839 common->cmnd[0] != SC_REQUEST_SENSE) {
1840 curlun->sense_data = curlun->unit_attention_data;
1841 curlun->unit_attention_data = SS_NO_SENSE;
1845 /* Check that only command bytes listed in the mask are non-zero */
1846 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1847 for (i = 1; i < cmnd_size; ++i) {
1848 if (common->cmnd[i] && !(mask & (1 << i))) {
1850 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1855 /* If the medium isn't mounted and the command needs to access
1856 * it, return an error. */
1857 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1858 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1866 static int do_scsi_command(struct fsg_common *common)
1868 struct fsg_buffhd *bh;
1870 int reply = -EINVAL;
1872 static char unknown[16];
1876 /* Wait for the next buffer to become available for data or status */
1877 bh = common->next_buffhd_to_fill;
1878 common->next_buffhd_to_drain = bh;
1879 while (bh->state != BUF_STATE_EMPTY) {
1880 rc = sleep_thread(common);
1884 common->phase_error = 0;
1885 common->short_packet_received = 0;
1887 down_read(&common->filesem); /* We're using the backing file */
1888 switch (common->cmnd[0]) {
1891 common->data_size_from_cmnd = common->cmnd[4];
1892 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1896 reply = do_inquiry(common, bh);
1899 case SC_MODE_SELECT_6:
1900 common->data_size_from_cmnd = common->cmnd[4];
1901 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1905 reply = do_mode_select(common, bh);
1908 case SC_MODE_SELECT_10:
1909 common->data_size_from_cmnd =
1910 get_unaligned_be16(&common->cmnd[7]);
1911 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1915 reply = do_mode_select(common, bh);
1918 case SC_MODE_SENSE_6:
1919 common->data_size_from_cmnd = common->cmnd[4];
1920 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1921 (1<<1) | (1<<2) | (1<<4), 0,
1924 reply = do_mode_sense(common, bh);
1927 case SC_MODE_SENSE_10:
1928 common->data_size_from_cmnd =
1929 get_unaligned_be16(&common->cmnd[7]);
1930 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1931 (1<<1) | (1<<2) | (3<<7), 0,
1934 reply = do_mode_sense(common, bh);
1937 case SC_PREVENT_ALLOW_MEDIUM_REMOVAL:
1938 common->data_size_from_cmnd = 0;
1939 reply = check_command(common, 6, DATA_DIR_NONE,
1941 "PREVENT-ALLOW MEDIUM REMOVAL");
1943 reply = do_prevent_allow(common);
1947 i = common->cmnd[4];
1948 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
1949 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1953 reply = do_read(common);
1957 common->data_size_from_cmnd =
1958 get_unaligned_be16(&common->cmnd[7]) << 9;
1959 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1960 (1<<1) | (0xf<<2) | (3<<7), 1,
1963 reply = do_read(common);
1967 common->data_size_from_cmnd =
1968 get_unaligned_be32(&common->cmnd[6]) << 9;
1969 reply = check_command(common, 12, DATA_DIR_TO_HOST,
1970 (1<<1) | (0xf<<2) | (0xf<<6), 1,
1973 reply = do_read(common);
1976 case SC_READ_CAPACITY:
1977 common->data_size_from_cmnd = 8;
1978 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1979 (0xf<<2) | (1<<8), 1,
1982 reply = do_read_capacity(common, bh);
1985 case SC_READ_HEADER:
1986 if (!common->curlun || !common->curlun->cdrom)
1988 common->data_size_from_cmnd =
1989 get_unaligned_be16(&common->cmnd[7]);
1990 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1991 (3<<7) | (0x1f<<1), 1,
1994 reply = do_read_header(common, bh);
1998 if (!common->curlun || !common->curlun->cdrom)
2000 common->data_size_from_cmnd =
2001 get_unaligned_be16(&common->cmnd[7]);
2002 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2006 reply = do_read_toc(common, bh);
2009 case SC_READ_FORMAT_CAPACITIES:
2010 common->data_size_from_cmnd =
2011 get_unaligned_be16(&common->cmnd[7]);
2012 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2014 "READ FORMAT CAPACITIES");
2016 reply = do_read_format_capacities(common, bh);
2019 case SC_REQUEST_SENSE:
2020 common->data_size_from_cmnd = common->cmnd[4];
2021 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2025 reply = do_request_sense(common, bh);
2028 case SC_START_STOP_UNIT:
2029 common->data_size_from_cmnd = 0;
2030 reply = check_command(common, 6, DATA_DIR_NONE,
2034 reply = do_start_stop(common);
2037 case SC_SYNCHRONIZE_CACHE:
2038 common->data_size_from_cmnd = 0;
2039 reply = check_command(common, 10, DATA_DIR_NONE,
2040 (0xf<<2) | (3<<7), 1,
2041 "SYNCHRONIZE CACHE");
2043 reply = do_synchronize_cache(common);
2046 case SC_TEST_UNIT_READY:
2047 common->data_size_from_cmnd = 0;
2048 reply = check_command(common, 6, DATA_DIR_NONE,
2053 /* Although optional, this command is used by MS-Windows. We
2054 * support a minimal version: BytChk must be 0. */
2056 common->data_size_from_cmnd = 0;
2057 reply = check_command(common, 10, DATA_DIR_NONE,
2058 (1<<1) | (0xf<<2) | (3<<7), 1,
2061 reply = do_verify(common);
2065 i = common->cmnd[4];
2066 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
2067 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
2071 reply = do_write(common);
2075 common->data_size_from_cmnd =
2076 get_unaligned_be16(&common->cmnd[7]) << 9;
2077 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
2078 (1<<1) | (0xf<<2) | (3<<7), 1,
2081 reply = do_write(common);
2085 common->data_size_from_cmnd =
2086 get_unaligned_be32(&common->cmnd[6]) << 9;
2087 reply = check_command(common, 12, DATA_DIR_FROM_HOST,
2088 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2091 reply = do_write(common);
2094 /* Some mandatory commands that we recognize but don't implement.
2095 * They don't mean much in this setting. It's left as an exercise
2096 * for anyone interested to implement RESERVE and RELEASE in terms
2097 * of Posix locks. */
2098 case SC_FORMAT_UNIT:
2101 case SC_SEND_DIAGNOSTIC:
2106 common->data_size_from_cmnd = 0;
2107 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2108 reply = check_command(common, common->cmnd_size,
2109 DATA_DIR_UNKNOWN, 0xff, 0, unknown);
2111 common->curlun->sense_data = SS_INVALID_COMMAND;
2116 up_read(&common->filesem);
2118 if (reply == -EINTR || signal_pending(current))
2121 /* Set up the single reply buffer for finish_reply() */
2122 if (reply == -EINVAL)
2123 reply = 0; /* Error reply length */
2124 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2125 reply = min((u32) reply, common->data_size_from_cmnd);
2126 bh->inreq->length = reply;
2127 bh->state = BUF_STATE_FULL;
2128 common->residue -= reply;
2129 } /* Otherwise it's already set */
2135 /*-------------------------------------------------------------------------*/
2137 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2139 struct usb_request *req = bh->outreq;
2140 struct fsg_bulk_cb_wrap *cbw = req->buf;
2141 struct fsg_common *common = fsg->common;
2143 /* Was this a real packet? Should it be ignored? */
2144 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2147 /* Is the CBW valid? */
2148 if (req->actual != USB_BULK_CB_WRAP_LEN ||
2149 cbw->Signature != cpu_to_le32(
2151 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2153 le32_to_cpu(cbw->Signature));
2155 /* The Bulk-only spec says we MUST stall the IN endpoint
2156 * (6.6.1), so it's unavoidable. It also says we must
2157 * retain this state until the next reset, but there's
2158 * no way to tell the controller driver it should ignore
2159 * Clear-Feature(HALT) requests.
2161 * We aren't required to halt the OUT endpoint; instead
2162 * we can simply accept and discard any data received
2163 * until the next reset. */
2164 wedge_bulk_in_endpoint(fsg);
2165 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2169 /* Is the CBW meaningful? */
2170 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG ||
2171 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2172 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2174 cbw->Lun, cbw->Flags, cbw->Length);
2176 /* We can do anything we want here, so let's stall the
2177 * bulk pipes if we are allowed to. */
2178 if (common->can_stall) {
2179 fsg_set_halt(fsg, fsg->bulk_out);
2180 halt_bulk_in_endpoint(fsg);
2185 /* Save the command for later */
2186 common->cmnd_size = cbw->Length;
2187 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2188 if (cbw->Flags & USB_BULK_IN_FLAG)
2189 common->data_dir = DATA_DIR_TO_HOST;
2191 common->data_dir = DATA_DIR_FROM_HOST;
2192 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2193 if (common->data_size == 0)
2194 common->data_dir = DATA_DIR_NONE;
2195 common->lun = cbw->Lun;
2196 common->tag = cbw->Tag;
2201 static int get_next_command(struct fsg_common *common)
2203 struct fsg_buffhd *bh;
2206 /* Wait for the next buffer to become available */
2207 bh = common->next_buffhd_to_fill;
2208 while (bh->state != BUF_STATE_EMPTY) {
2209 rc = sleep_thread(common);
2214 /* Queue a request to read a Bulk-only CBW */
2215 set_bulk_out_req_length(common, bh, USB_BULK_CB_WRAP_LEN);
2216 bh->outreq->short_not_ok = 1;
2217 START_TRANSFER_OR(common, bulk_out, bh->outreq,
2218 &bh->outreq_busy, &bh->state)
2219 /* Don't know what to do if common->fsg is NULL */
2222 /* We will drain the buffer in software, which means we
2223 * can reuse it for the next filling. No need to advance
2224 * next_buffhd_to_fill. */
2226 /* Wait for the CBW to arrive */
2227 while (bh->state != BUF_STATE_FULL) {
2228 rc = sleep_thread(common);
2233 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2234 bh->state = BUF_STATE_EMPTY;
2240 /*-------------------------------------------------------------------------*/
2242 static int enable_endpoint(struct fsg_common *common, struct usb_ep *ep,
2243 const struct usb_endpoint_descriptor *d)
2247 ep->driver_data = common;
2248 rc = usb_ep_enable(ep, d);
2250 ERROR(common, "can't enable %s, result %d\n", ep->name, rc);
2254 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2255 struct usb_request **preq)
2257 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2260 ERROR(common, "can't allocate request for %s\n", ep->name);
2265 * Reset interface setting and re-init endpoint state (toggle etc).
2266 * Call with altsetting < 0 to disable the interface. The only other
2267 * available altsetting is 0, which enables the interface.
2269 static int do_set_interface(struct fsg_common *common, int altsetting)
2273 const struct usb_endpoint_descriptor *d;
2275 if (common->running)
2276 DBG(common, "reset interface\n");
2279 /* Deallocate the requests */
2280 if (common->prev_fsg) {
2281 struct fsg_dev *fsg = common->prev_fsg;
2283 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2284 struct fsg_buffhd *bh = &common->buffhds[i];
2287 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2291 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2296 /* Disable the endpoints */
2297 if (fsg->bulk_in_enabled) {
2298 usb_ep_disable(fsg->bulk_in);
2299 fsg->bulk_in_enabled = 0;
2301 if (fsg->bulk_out_enabled) {
2302 usb_ep_disable(fsg->bulk_out);
2303 fsg->bulk_out_enabled = 0;
2306 common->prev_fsg = 0;
2309 common->running = 0;
2310 if (altsetting < 0 || rc != 0)
2313 DBG(common, "set interface %d\n", altsetting);
2315 if (fsg_is_set(common)) {
2316 struct fsg_dev *fsg = common->fsg;
2317 common->prev_fsg = common->fsg;
2319 /* Enable the endpoints */
2320 d = fsg_ep_desc(common->gadget,
2321 &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
2322 rc = enable_endpoint(common, fsg->bulk_in, d);
2325 fsg->bulk_in_enabled = 1;
2327 d = fsg_ep_desc(common->gadget,
2328 &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
2329 rc = enable_endpoint(common, fsg->bulk_out, d);
2332 fsg->bulk_out_enabled = 1;
2333 common->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
2334 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2336 /* Allocate the requests */
2337 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2338 struct fsg_buffhd *bh = &common->buffhds[i];
2340 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2343 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2346 bh->inreq->buf = bh->outreq->buf = bh->buf;
2347 bh->inreq->context = bh->outreq->context = bh;
2348 bh->inreq->complete = bulk_in_complete;
2349 bh->outreq->complete = bulk_out_complete;
2352 common->running = 1;
2353 for (i = 0; i < common->nluns; ++i)
2354 common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
2363 * Change our operational configuration. This code must agree with the code
2364 * that returns config descriptors, and with interface altsetting code.
2366 * It's also responsible for power management interactions. Some
2367 * configurations might not work with our current power sources.
2368 * For now we just assume the gadget is always self-powered.
2370 static int do_set_config(struct fsg_common *common, u8 new_config)
2374 /* Disable the single interface */
2375 if (common->config != 0) {
2376 DBG(common, "reset config\n");
2378 rc = do_set_interface(common, -1);
2381 /* Enable the interface */
2382 if (new_config != 0) {
2383 common->config = new_config;
2384 rc = do_set_interface(common, 0);
2386 common->config = 0; /* Reset on errors */
2392 /****************************** ALT CONFIGS ******************************/
2395 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2397 struct fsg_dev *fsg = fsg_from_func(f);
2398 fsg->common->prev_fsg = fsg->common->fsg;
2399 fsg->common->fsg = fsg;
2400 fsg->common->new_config = 1;
2401 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2405 static void fsg_disable(struct usb_function *f)
2407 struct fsg_dev *fsg = fsg_from_func(f);
2408 fsg->common->prev_fsg = fsg->common->fsg;
2409 fsg->common->fsg = fsg;
2410 fsg->common->new_config = 0;
2411 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2415 /*-------------------------------------------------------------------------*/
2417 static void handle_exception(struct fsg_common *common)
2422 struct fsg_buffhd *bh;
2423 enum fsg_state old_state;
2425 struct fsg_lun *curlun;
2426 unsigned int exception_req_tag;
2429 /* Clear the existing signals. Anything but SIGUSR1 is converted
2430 * into a high-priority EXIT exception. */
2432 sig = dequeue_signal_lock(current, ¤t->blocked, &info);
2435 if (sig != SIGUSR1) {
2436 if (common->state < FSG_STATE_EXIT)
2437 DBG(common, "Main thread exiting on signal\n");
2438 raise_exception(common, FSG_STATE_EXIT);
2442 /* Cancel all the pending transfers */
2443 if (fsg_is_set(common)) {
2444 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2445 bh = &common->buffhds[i];
2447 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2448 if (bh->outreq_busy)
2449 usb_ep_dequeue(common->fsg->bulk_out,
2453 /* Wait until everything is idle */
2456 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2457 bh = &common->buffhds[i];
2458 num_active += bh->inreq_busy + bh->outreq_busy;
2460 if (num_active == 0)
2462 if (sleep_thread(common))
2466 /* Clear out the controller's fifos */
2467 if (common->fsg->bulk_in_enabled)
2468 usb_ep_fifo_flush(common->fsg->bulk_in);
2469 if (common->fsg->bulk_out_enabled)
2470 usb_ep_fifo_flush(common->fsg->bulk_out);
2473 /* Reset the I/O buffer states and pointers, the SCSI
2474 * state, and the exception. Then invoke the handler. */
2475 spin_lock_irq(&common->lock);
2477 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2478 bh = &common->buffhds[i];
2479 bh->state = BUF_STATE_EMPTY;
2481 common->next_buffhd_to_fill = &common->buffhds[0];
2482 common->next_buffhd_to_drain = &common->buffhds[0];
2483 exception_req_tag = common->exception_req_tag;
2484 new_config = common->new_config;
2485 old_state = common->state;
2487 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2488 common->state = FSG_STATE_STATUS_PHASE;
2490 for (i = 0; i < common->nluns; ++i) {
2491 curlun = &common->luns[i];
2492 curlun->prevent_medium_removal = 0;
2493 curlun->sense_data = SS_NO_SENSE;
2494 curlun->unit_attention_data = SS_NO_SENSE;
2495 curlun->sense_data_info = 0;
2496 curlun->info_valid = 0;
2498 common->state = FSG_STATE_IDLE;
2500 spin_unlock_irq(&common->lock);
2502 /* Carry out any extra actions required for the exception */
2503 switch (old_state) {
2504 case FSG_STATE_ABORT_BULK_OUT:
2505 send_status(common);
2506 spin_lock_irq(&common->lock);
2507 if (common->state == FSG_STATE_STATUS_PHASE)
2508 common->state = FSG_STATE_IDLE;
2509 spin_unlock_irq(&common->lock);
2512 case FSG_STATE_RESET:
2513 /* In case we were forced against our will to halt a
2514 * bulk endpoint, clear the halt now. (The SuperH UDC
2515 * requires this.) */
2516 if (!fsg_is_set(common))
2518 if (test_and_clear_bit(IGNORE_BULK_OUT,
2519 &common->fsg->atomic_bitflags))
2520 usb_ep_clear_halt(common->fsg->bulk_in);
2522 if (common->ep0_req_tag == exception_req_tag)
2523 ep0_queue(common); /* Complete the status stage */
2525 /* Technically this should go here, but it would only be
2526 * a waste of time. Ditto for the INTERFACE_CHANGE and
2527 * CONFIG_CHANGE cases. */
2528 /* for (i = 0; i < common->nluns; ++i) */
2529 /* common->luns[i].unit_attention_data = */
2530 /* SS_RESET_OCCURRED; */
2533 case FSG_STATE_CONFIG_CHANGE:
2534 rc = do_set_config(common, new_config);
2537 case FSG_STATE_EXIT:
2538 case FSG_STATE_TERMINATED:
2539 do_set_config(common, 0); /* Free resources */
2540 spin_lock_irq(&common->lock);
2541 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2542 spin_unlock_irq(&common->lock);
2545 case FSG_STATE_INTERFACE_CHANGE:
2546 case FSG_STATE_DISCONNECT:
2547 case FSG_STATE_COMMAND_PHASE:
2548 case FSG_STATE_DATA_PHASE:
2549 case FSG_STATE_STATUS_PHASE:
2550 case FSG_STATE_IDLE:
2556 /*-------------------------------------------------------------------------*/
2558 static int fsg_main_thread(void *common_)
2560 struct fsg_common *common = common_;
2562 /* Allow the thread to be killed by a signal, but set the signal mask
2563 * to block everything but INT, TERM, KILL, and USR1. */
2564 allow_signal(SIGINT);
2565 allow_signal(SIGTERM);
2566 allow_signal(SIGKILL);
2567 allow_signal(SIGUSR1);
2569 /* Allow the thread to be frozen */
2572 /* Arrange for userspace references to be interpreted as kernel
2573 * pointers. That way we can pass a kernel pointer to a routine
2574 * that expects a __user pointer and it will work okay. */
2578 while (common->state != FSG_STATE_TERMINATED) {
2579 if (exception_in_progress(common) || signal_pending(current)) {
2580 handle_exception(common);
2584 if (!common->running) {
2585 sleep_thread(common);
2589 if (get_next_command(common))
2592 spin_lock_irq(&common->lock);
2593 if (!exception_in_progress(common))
2594 common->state = FSG_STATE_DATA_PHASE;
2595 spin_unlock_irq(&common->lock);
2597 if (do_scsi_command(common) || finish_reply(common))
2600 spin_lock_irq(&common->lock);
2601 if (!exception_in_progress(common))
2602 common->state = FSG_STATE_STATUS_PHASE;
2603 spin_unlock_irq(&common->lock);
2605 if (send_status(common))
2608 spin_lock_irq(&common->lock);
2609 if (!exception_in_progress(common))
2610 common->state = FSG_STATE_IDLE;
2611 spin_unlock_irq(&common->lock);
2614 spin_lock_irq(&common->lock);
2615 common->thread_task = NULL;
2616 spin_unlock_irq(&common->lock);
2618 if (!common->thread_exits || common->thread_exits(common) < 0) {
2619 struct fsg_lun *curlun = common->luns;
2620 unsigned i = common->nluns;
2622 down_write(&common->filesem);
2623 for (; i--; ++curlun) {
2624 if (!fsg_lun_is_open(curlun))
2627 fsg_lun_close(curlun);
2628 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
2630 up_write(&common->filesem);
2633 /* Let the unbind and cleanup routines know the thread has exited */
2634 complete_and_exit(&common->thread_notifier, 0);
2638 /*************************** DEVICE ATTRIBUTES ***************************/
2640 /* Write permission is checked per LUN in store_*() functions. */
2641 static DEVICE_ATTR(ro, 0644, fsg_show_ro, fsg_store_ro);
2642 static DEVICE_ATTR(file, 0644, fsg_show_file, fsg_store_file);
2645 /****************************** FSG COMMON ******************************/
2647 static void fsg_common_release(struct kref *ref);
2649 static void fsg_lun_release(struct device *dev)
2651 /* Nothing needs to be done */
2654 static inline void fsg_common_get(struct fsg_common *common)
2656 kref_get(&common->ref);
2659 static inline void fsg_common_put(struct fsg_common *common)
2661 kref_put(&common->ref, fsg_common_release);
2665 static struct fsg_common *fsg_common_init(struct fsg_common *common,
2666 struct usb_composite_dev *cdev,
2667 struct fsg_config *cfg)
2669 struct usb_gadget *gadget = cdev->gadget;
2670 struct fsg_buffhd *bh;
2671 struct fsg_lun *curlun;
2672 struct fsg_lun_config *lcfg;
2676 /* Find out how many LUNs there should be */
2678 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2679 dev_err(&gadget->dev, "invalid number of LUNs: %u\n", nluns);
2680 return ERR_PTR(-EINVAL);
2685 common = kzalloc(sizeof *common, GFP_KERNEL);
2687 return ERR_PTR(-ENOMEM);
2688 common->free_storage_on_release = 1;
2690 memset(common, 0, sizeof common);
2691 common->free_storage_on_release = 0;
2694 common->private_data = cfg->private_data;
2696 common->gadget = gadget;
2697 common->ep0 = gadget->ep0;
2698 common->ep0req = cdev->req;
2700 /* Maybe allocate device-global string IDs, and patch descriptors */
2701 if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
2702 rc = usb_string_id(cdev);
2707 fsg_strings[FSG_STRING_INTERFACE].id = rc;
2708 fsg_intf_desc.iInterface = rc;
2711 /* Create the LUNs, open their backing files, and register the
2712 * LUN devices in sysfs. */
2713 curlun = kzalloc(nluns * sizeof *curlun, GFP_KERNEL);
2716 return ERR_PTR(-ENOMEM);
2718 common->luns = curlun;
2720 init_rwsem(&common->filesem);
2722 for (i = 0, lcfg = cfg->luns; i < nluns; ++i, ++curlun, ++lcfg) {
2723 curlun->cdrom = !!lcfg->cdrom;
2724 curlun->ro = lcfg->cdrom || lcfg->ro;
2725 curlun->removable = lcfg->removable;
2726 curlun->dev.release = fsg_lun_release;
2727 curlun->dev.parent = &gadget->dev;
2728 /* curlun->dev.driver = &fsg_driver.driver; XXX */
2729 dev_set_drvdata(&curlun->dev, &common->filesem);
2730 dev_set_name(&curlun->dev,
2731 cfg->lun_name_format
2732 ? cfg->lun_name_format
2736 rc = device_register(&curlun->dev);
2738 INFO(common, "failed to register LUN%d: %d\n", i, rc);
2743 rc = device_create_file(&curlun->dev, &dev_attr_ro);
2746 rc = device_create_file(&curlun->dev, &dev_attr_file);
2750 if (lcfg->filename) {
2751 rc = fsg_lun_open(curlun, lcfg->filename);
2754 } else if (!curlun->removable) {
2755 ERROR(common, "no file given for LUN%d\n", i);
2760 common->nluns = nluns;
2763 /* Data buffers cyclic list */
2764 bh = common->buffhds;
2765 i = FSG_NUM_BUFFERS;
2766 goto buffhds_first_it;
2771 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2772 if (unlikely(!bh->buf)) {
2777 bh->next = common->buffhds;
2780 /* Prepare inquiryString */
2781 if (cfg->release != 0xffff) {
2784 i = usb_gadget_controller_number(gadget);
2788 WARNING(common, "controller '%s' not recognized\n",
2793 #define OR(x, y) ((x) ? (x) : (y))
2794 snprintf(common->inquiry_string, sizeof common->inquiry_string,
2796 OR(cfg->vendor_name, "Linux "),
2797 /* Assume product name dependent on the first LUN */
2798 OR(cfg->product_name, common->luns->cdrom
2799 ? "File-Stor Gadget"
2800 : "File-CD Gadget "),
2804 /* Some peripheral controllers are known not to be able to
2805 * halt bulk endpoints correctly. If one of them is present,
2808 common->can_stall = cfg->can_stall &&
2809 !(gadget_is_at91(common->gadget));
2812 spin_lock_init(&common->lock);
2813 kref_init(&common->ref);
2816 /* Tell the thread to start working */
2817 common->thread_exits = cfg->thread_exits;
2818 common->thread_task =
2819 kthread_create(fsg_main_thread, common,
2820 OR(cfg->thread_name, "file-storage"));
2821 if (IS_ERR(common->thread_task)) {
2822 rc = PTR_ERR(common->thread_task);
2825 init_completion(&common->thread_notifier);
2830 INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2831 INFO(common, "Number of LUNs=%d\n", common->nluns);
2833 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2834 for (i = 0, nluns = common->nluns, curlun = common->luns;
2837 char *p = "(no medium)";
2838 if (fsg_lun_is_open(curlun)) {
2841 p = d_path(&curlun->filp->f_path,
2847 LINFO(curlun, "LUN: %s%s%sfile: %s\n",
2848 curlun->removable ? "removable " : "",
2849 curlun->ro ? "read only " : "",
2850 curlun->cdrom ? "CD-ROM " : "",
2855 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
2857 wake_up_process(common->thread_task);
2863 common->nluns = i + 1;
2865 common->state = FSG_STATE_TERMINATED; /* The thread is dead */
2866 /* Call fsg_common_release() directly, ref might be not
2868 fsg_common_release(&common->ref);
2873 static void fsg_common_release(struct kref *ref)
2875 struct fsg_common *common =
2876 container_of(ref, struct fsg_common, ref);
2877 unsigned i = common->nluns;
2878 struct fsg_lun *lun = common->luns;
2879 struct fsg_buffhd *bh;
2881 /* If the thread isn't already dead, tell it to exit now */
2882 if (common->state != FSG_STATE_TERMINATED) {
2883 raise_exception(common, FSG_STATE_EXIT);
2884 wait_for_completion(&common->thread_notifier);
2886 /* The cleanup routine waits for this completion also */
2887 complete(&common->thread_notifier);
2890 /* Beware tempting for -> do-while optimization: when in error
2891 * recovery nluns may be zero. */
2893 for (; i; --i, ++lun) {
2894 device_remove_file(&lun->dev, &dev_attr_ro);
2895 device_remove_file(&lun->dev, &dev_attr_file);
2897 device_unregister(&lun->dev);
2900 kfree(common->luns);
2902 i = FSG_NUM_BUFFERS;
2903 bh = common->buffhds;
2906 } while (++bh, --i);
2908 if (common->free_storage_on_release)
2913 /*-------------------------------------------------------------------------*/
2916 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
2918 struct fsg_dev *fsg = fsg_from_func(f);
2920 DBG(fsg, "unbind\n");
2921 fsg_common_put(fsg->common);
2926 static int __init fsg_bind(struct usb_configuration *c, struct usb_function *f)
2928 struct fsg_dev *fsg = fsg_from_func(f);
2929 struct usb_gadget *gadget = c->cdev->gadget;
2934 fsg->gadget = gadget;
2937 i = usb_interface_id(c, f);
2940 fsg_intf_desc.bInterfaceNumber = i;
2941 fsg->interface_number = i;
2943 /* Find all the endpoints we will use */
2944 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
2947 ep->driver_data = fsg->common; /* claim the endpoint */
2950 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
2953 ep->driver_data = fsg->common; /* claim the endpoint */
2956 if (gadget_is_dualspeed(gadget)) {
2957 /* Assume endpoint addresses are the same for both speeds */
2958 fsg_hs_bulk_in_desc.bEndpointAddress =
2959 fsg_fs_bulk_in_desc.bEndpointAddress;
2960 fsg_hs_bulk_out_desc.bEndpointAddress =
2961 fsg_fs_bulk_out_desc.bEndpointAddress;
2962 f->hs_descriptors = fsg_hs_function;
2968 ERROR(fsg, "unable to autoconfigure all endpoints\n");
2974 /****************************** ADD FUNCTION ******************************/
2976 static struct usb_gadget_strings *fsg_strings_array[] = {
2981 static int fsg_add(struct usb_composite_dev *cdev,
2982 struct usb_configuration *c,
2983 struct fsg_common *common)
2985 struct fsg_dev *fsg;
2988 fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
2992 fsg->function.name = FSG_DRIVER_DESC;
2993 fsg->function.strings = fsg_strings_array;
2994 fsg->function.descriptors = fsg_fs_function;
2995 fsg->function.bind = fsg_bind;
2996 fsg->function.unbind = fsg_unbind;
2997 fsg->function.setup = fsg_setup;
2998 fsg->function.set_alt = fsg_set_alt;
2999 fsg->function.disable = fsg_disable;
3001 fsg->common = common;
3002 /* Our caller holds a reference to common structure so we
3003 * don't have to be worry about it being freed until we return
3004 * from this function. So instead of incrementing counter now
3005 * and decrement in error recovery we increment it only when
3006 * call to usb_add_function() was successful. */
3008 rc = usb_add_function(c, &fsg->function);
3010 if (likely(rc == 0))
3011 fsg_common_get(fsg->common);
3020 /************************* Module parameters *************************/
3023 struct fsg_module_parameters {
3024 char *file[FSG_MAX_LUNS];
3025 int ro[FSG_MAX_LUNS];
3026 int removable[FSG_MAX_LUNS];
3027 int cdrom[FSG_MAX_LUNS];
3029 unsigned int file_count, ro_count, removable_count, cdrom_count;
3030 unsigned int luns; /* nluns */
3031 int stall; /* can_stall */
3035 #define _FSG_MODULE_PARAM_ARRAY(prefix, params, name, type, desc) \
3036 module_param_array_named(prefix ## name, params.name, type, \
3037 &prefix ## params.name ## _count, \
3039 MODULE_PARM_DESC(prefix ## name, desc)
3041 #define _FSG_MODULE_PARAM(prefix, params, name, type, desc) \
3042 module_param_named(prefix ## name, params.name, type, \
3044 MODULE_PARM_DESC(prefix ## name, desc)
3046 #define FSG_MODULE_PARAMETERS(prefix, params) \
3047 _FSG_MODULE_PARAM_ARRAY(prefix, params, file, charp, \
3048 "names of backing files or devices"); \
3049 _FSG_MODULE_PARAM_ARRAY(prefix, params, ro, bool, \
3050 "true to force read-only"); \
3051 _FSG_MODULE_PARAM_ARRAY(prefix, params, removable, bool, \
3052 "true to simulate removable media"); \
3053 _FSG_MODULE_PARAM_ARRAY(prefix, params, cdrom, bool, \
3054 "true to simulate CD-ROM instead of disk"); \
3055 _FSG_MODULE_PARAM(prefix, params, luns, uint, \
3056 "number of LUNs"); \
3057 _FSG_MODULE_PARAM(prefix, params, stall, bool, \
3058 "false to prevent bulk stalls")
3062 fsg_config_from_params(struct fsg_config *cfg,
3063 const struct fsg_module_parameters *params)
3065 struct fsg_lun_config *lun;
3068 /* Configure LUNs */
3070 min(params->luns ?: (params->file_count ?: 1u),
3071 (unsigned)FSG_MAX_LUNS);
3072 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3073 lun->ro = !!params->ro[i];
3074 lun->cdrom = !!params->cdrom[i];
3075 lun->removable = /* Removable by default */
3076 params->removable_count <= i || params->removable[i];
3078 params->file_count > i && params->file[i][0]
3083 /* Let MSF use defaults */
3084 cfg->lun_name_format = 0;
3085 cfg->thread_name = 0;
3086 cfg->vendor_name = 0;
3087 cfg->product_name = 0;
3088 cfg->release = 0xffff;
3090 cfg->thread_exits = 0;
3091 cfg->private_data = 0;
3094 cfg->can_stall = params->stall;
3097 static inline struct fsg_common *
3098 fsg_common_from_params(struct fsg_common *common,
3099 struct usb_composite_dev *cdev,
3100 const struct fsg_module_parameters *params)
3101 __attribute__((unused));
3102 static inline struct fsg_common *
3103 fsg_common_from_params(struct fsg_common *common,
3104 struct usb_composite_dev *cdev,
3105 const struct fsg_module_parameters *params)
3107 struct fsg_config cfg;
3108 fsg_config_from_params(&cfg, params);
3109 return fsg_common_init(common, cdev, &cfg);