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>
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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
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24 * Foundation, either version 2 of that License or (at your option) any
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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.
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 * nofua=b[,b...] Default false, booleans for ignore FUA flag
131 * in SCSI WRITE(10,12) commands
132 * luns=N Default N = number of filenames, number of
134 * stall Default determined according to the type of
135 * USB device controller (usually true),
136 * boolean to permit the driver to halt
139 * The module parameters may be prefixed with some string. You need
140 * to consult gadget's documentation or source to verify whether it is
141 * using those module parameters and if it does what are the prefixes
142 * (look for FSG_MODULE_PARAMETERS() macro usage, what's inside it is
146 * Requirements are modest; only a bulk-in and a bulk-out endpoint are
147 * needed. The memory requirement amounts to two 16K buffers, size
148 * configurable by a parameter. Support is included for both
149 * full-speed and high-speed operation.
151 * Note that the driver is slightly non-portable in that it assumes a
152 * single memory/DMA buffer will be useable for bulk-in, bulk-out, and
153 * interrupt-in endpoints. With most device controllers this isn't an
154 * issue, but there may be some with hardware restrictions that prevent
155 * a buffer from being used by more than one endpoint.
158 * The pathnames of the backing files and the ro settings are
159 * available in the attribute files "file" and "ro" in the lun<n> (or
160 * to be more precise in a directory which name comes from
161 * "lun_name_format" option!) subdirectory of the gadget's sysfs
162 * directory. If the "removable" option is set, writing to these
163 * files will simulate ejecting/loading the medium (writing an empty
164 * line means eject) and adjusting a write-enable tab. Changes to the
165 * ro setting are not allowed when the medium is loaded or if CD-ROM
166 * emulation is being used.
168 * When a LUN receive an "eject" SCSI request (Start/Stop Unit),
169 * if the LUN is removable, the backing file is released to simulate
173 * This function is heavily based on "File-backed Storage Gadget" by
174 * Alan Stern which in turn is heavily based on "Gadget Zero" by David
175 * Brownell. The driver's SCSI command interface was based on the
176 * "Information technology - Small Computer System Interface - 2"
177 * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
178 * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
179 * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
180 * was based on the "Universal Serial Bus Mass Storage Class UFI
181 * Command Specification" document, Revision 1.0, December 14, 1998,
183 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
189 * The MSF is fairly straightforward. There is a main kernel
190 * thread that handles most of the work. Interrupt routines field
191 * callbacks from the controller driver: bulk- and interrupt-request
192 * completion notifications, endpoint-0 events, and disconnect events.
193 * Completion events are passed to the main thread by wakeup calls. Many
194 * ep0 requests are handled at interrupt time, but SetInterface,
195 * SetConfiguration, and device reset requests are forwarded to the
196 * thread in the form of "exceptions" using SIGUSR1 signals (since they
197 * should interrupt any ongoing file I/O operations).
199 * The thread's main routine implements the standard command/data/status
200 * parts of a SCSI interaction. It and its subroutines are full of tests
201 * for pending signals/exceptions -- all this polling is necessary since
202 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
203 * indication that the driver really wants to be running in userspace.)
204 * An important point is that so long as the thread is alive it keeps an
205 * open reference to the backing file. This will prevent unmounting
206 * the backing file's underlying filesystem and could cause problems
207 * during system shutdown, for example. To prevent such problems, the
208 * thread catches INT, TERM, and KILL signals and converts them into
211 * In normal operation the main thread is started during the gadget's
212 * fsg_bind() callback and stopped during fsg_unbind(). But it can
213 * also exit when it receives a signal, and there's no point leaving
214 * the gadget running when the thread is dead. At of this moment, MSF
215 * provides no way to deregister the gadget when thread dies -- maybe
216 * a callback functions is needed.
218 * To provide maximum throughput, the driver uses a circular pipeline of
219 * buffer heads (struct fsg_buffhd). In principle the pipeline can be
220 * arbitrarily long; in practice the benefits don't justify having more
221 * than 2 stages (i.e., double buffering). But it helps to think of the
222 * pipeline as being a long one. Each buffer head contains a bulk-in and
223 * a bulk-out request pointer (since the buffer can be used for both
224 * output and input -- directions always are given from the host's
225 * point of view) as well as a pointer to the buffer and various state
228 * Use of the pipeline follows a simple protocol. There is a variable
229 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
230 * At any time that buffer head may still be in use from an earlier
231 * request, so each buffer head has a state variable indicating whether
232 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
233 * buffer head to be EMPTY, filling the buffer either by file I/O or by
234 * USB I/O (during which the buffer head is BUSY), and marking the buffer
235 * head FULL when the I/O is complete. Then the buffer will be emptied
236 * (again possibly by USB I/O, during which it is marked BUSY) and
237 * finally marked EMPTY again (possibly by a completion routine).
239 * A module parameter tells the driver to avoid stalling the bulk
240 * endpoints wherever the transport specification allows. This is
241 * necessary for some UDCs like the SuperH, which cannot reliably clear a
242 * halt on a bulk endpoint. However, under certain circumstances the
243 * Bulk-only specification requires a stall. In such cases the driver
244 * will halt the endpoint and set a flag indicating that it should clear
245 * the halt in software during the next device reset. Hopefully this
246 * will permit everything to work correctly. Furthermore, although the
247 * specification allows the bulk-out endpoint to halt when the host sends
248 * too much data, implementing this would cause an unavoidable race.
249 * The driver will always use the "no-stall" approach for OUT transfers.
251 * One subtle point concerns sending status-stage responses for ep0
252 * requests. Some of these requests, such as device reset, can involve
253 * interrupting an ongoing file I/O operation, which might take an
254 * arbitrarily long time. During that delay the host might give up on
255 * the original ep0 request and issue a new one. When that happens the
256 * driver should not notify the host about completion of the original
257 * request, as the host will no longer be waiting for it. So the driver
258 * assigns to each ep0 request a unique tag, and it keeps track of the
259 * tag value of the request associated with a long-running exception
260 * (device-reset, interface-change, or configuration-change). When the
261 * exception handler is finished, the status-stage response is submitted
262 * only if the current ep0 request tag is equal to the exception request
263 * tag. Thus only the most recently received ep0 request will get a
264 * status-stage response.
266 * Warning: This driver source file is too long. It ought to be split up
267 * into a header file plus about 3 separate .c files, to handle the details
268 * of the Gadget, USB Mass Storage, and SCSI protocols.
272 /* #define VERBOSE_DEBUG */
273 /* #define DUMP_MSGS */
275 #include <linux/blkdev.h>
276 #include <linux/completion.h>
277 #include <linux/dcache.h>
278 #include <linux/delay.h>
279 #include <linux/device.h>
280 #include <linux/fcntl.h>
281 #include <linux/file.h>
282 #include <linux/fs.h>
283 #include <linux/kref.h>
284 #include <linux/kthread.h>
285 #include <linux/limits.h>
286 #include <linux/rwsem.h>
287 #include <linux/slab.h>
288 #include <linux/spinlock.h>
289 #include <linux/string.h>
290 #include <linux/freezer.h>
291 #include <linux/utsname.h>
293 #include <linux/usb/ch9.h>
294 #include <linux/usb/gadget.h>
295 #include <linux/usb/composite.h>
297 #include "gadget_chips.h"
300 /*------------------------------------------------------------------------*/
302 #define FSG_DRIVER_DESC "Mass Storage Function"
303 #define FSG_DRIVER_VERSION "2009/09/11"
305 static const char fsg_string_interface[] = "Mass Storage";
307 #define FSG_NO_INTR_EP 1
308 #define FSG_NO_DEVICE_STRINGS 1
310 #define FSG_NO_INTR_EP 1
312 #include "storage_common.c"
315 /*-------------------------------------------------------------------------*/
320 /* FSF callback functions */
321 struct fsg_operations {
323 * Callback function to call when thread exits. If no
324 * callback is set or it returns value lower then zero MSF
325 * will force eject all LUNs it operates on (including those
326 * marked as non-removable or with prevent_medium_removal flag
329 int (*thread_exits)(struct fsg_common *common);
332 * Called prior to ejection. Negative return means error,
333 * zero means to continue with ejection, positive means not to
336 int (*pre_eject)(struct fsg_common *common,
337 struct fsg_lun *lun, int num);
339 * Called after ejection. Negative return means error, zero
340 * or positive is just a success.
342 int (*post_eject)(struct fsg_common *common,
343 struct fsg_lun *lun, int num);
346 /* Data shared by all the FSG instances. */
348 struct usb_gadget *gadget;
349 struct usb_composite_dev *cdev;
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;
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 ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
619 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
621 switch (ctrl->bRequest) {
623 case USB_BULK_RESET_REQUEST:
624 if (ctrl->bRequestType !=
625 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
627 if (w_index != fsg->interface_number || w_value != 0 ||
632 * Raise an exception to stop the current operation
633 * and reinitialize our state.
635 DBG(fsg, "bulk reset request\n");
636 raise_exception(fsg->common, FSG_STATE_RESET);
637 return DELAYED_STATUS;
639 case USB_BULK_GET_MAX_LUN_REQUEST:
640 if (ctrl->bRequestType !=
641 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
643 if (w_index != fsg->interface_number || w_value != 0 ||
646 VDBG(fsg, "get max LUN\n");
647 *(u8 *)req->buf = fsg->common->nluns - 1;
649 /* Respond with data/status */
650 req->length = min((u16)1, w_length);
651 return ep0_queue(fsg->common);
655 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
656 ctrl->bRequestType, ctrl->bRequest,
657 le16_to_cpu(ctrl->wValue), w_index, w_length);
662 /*-------------------------------------------------------------------------*/
664 /* All the following routines run in process context */
666 /* Use this for bulk or interrupt transfers, not ep0 */
667 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
668 struct usb_request *req, int *pbusy,
669 enum fsg_buffer_state *state)
673 if (ep == fsg->bulk_in)
674 dump_msg(fsg, "bulk-in", req->buf, req->length);
676 spin_lock_irq(&fsg->common->lock);
678 *state = BUF_STATE_BUSY;
679 spin_unlock_irq(&fsg->common->lock);
680 rc = usb_ep_queue(ep, req, GFP_KERNEL);
683 *state = BUF_STATE_EMPTY;
685 /* We can't do much more than wait for a reset */
688 * Note: currently the net2280 driver fails zero-length
689 * submissions if DMA is enabled.
691 if (rc != -ESHUTDOWN &&
692 !(rc == -EOPNOTSUPP && req->length == 0))
693 WARNING(fsg, "error in submission: %s --> %d\n",
698 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
700 if (!fsg_is_set(common))
702 start_transfer(common->fsg, common->fsg->bulk_in,
703 bh->inreq, &bh->inreq_busy, &bh->state);
707 static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
709 if (!fsg_is_set(common))
711 start_transfer(common->fsg, common->fsg->bulk_out,
712 bh->outreq, &bh->outreq_busy, &bh->state);
716 static int sleep_thread(struct fsg_common *common)
720 /* Wait until a signal arrives or we are woken up */
723 set_current_state(TASK_INTERRUPTIBLE);
724 if (signal_pending(current)) {
728 if (common->thread_wakeup_needed)
732 __set_current_state(TASK_RUNNING);
733 common->thread_wakeup_needed = 0;
738 /*-------------------------------------------------------------------------*/
740 static int do_read(struct fsg_common *common)
742 struct fsg_lun *curlun = common->curlun;
744 struct fsg_buffhd *bh;
747 loff_t file_offset, file_offset_tmp;
752 * Get the starting Logical Block Address and check that it's
755 if (common->cmnd[0] == READ_6)
756 lba = get_unaligned_be24(&common->cmnd[1]);
758 lba = get_unaligned_be32(&common->cmnd[2]);
761 * We allow DPO (Disable Page Out = don't save data in the
762 * cache) and FUA (Force Unit Access = don't read from the
763 * cache), but we don't implement them.
765 if ((common->cmnd[1] & ~0x18) != 0) {
766 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
770 if (lba >= curlun->num_sectors) {
771 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
774 file_offset = ((loff_t) lba) << curlun->blkbits;
776 /* Carry out the file reads */
777 amount_left = common->data_size_from_cmnd;
778 if (unlikely(amount_left == 0))
779 return -EIO; /* No default reply */
783 * Figure out how much we need to read:
784 * Try to read the remaining amount.
785 * But don't read more than the buffer size.
786 * And don't try to read past the end of the file.
788 amount = min(amount_left, FSG_BUFLEN);
789 amount = min((loff_t)amount,
790 curlun->file_length - file_offset);
792 /* Wait for the next buffer to become available */
793 bh = common->next_buffhd_to_fill;
794 while (bh->state != BUF_STATE_EMPTY) {
795 rc = sleep_thread(common);
801 * If we were asked to read past the end of file,
802 * end with an empty buffer.
806 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
807 curlun->sense_data_info =
808 file_offset >> curlun->blkbits;
809 curlun->info_valid = 1;
810 bh->inreq->length = 0;
811 bh->state = BUF_STATE_FULL;
815 /* Perform the read */
816 file_offset_tmp = file_offset;
817 nread = vfs_read(curlun->filp,
818 (char __user *)bh->buf,
819 amount, &file_offset_tmp);
820 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
821 (unsigned long long)file_offset, (int)nread);
822 if (signal_pending(current))
826 LDBG(curlun, "error in file read: %d\n", (int)nread);
828 } else if (nread < amount) {
829 LDBG(curlun, "partial file read: %d/%u\n",
831 nread = round_down(nread, curlun->blksize);
833 file_offset += nread;
834 amount_left -= nread;
835 common->residue -= nread;
838 * Except at the end of the transfer, nread will be
839 * equal to the buffer size, which is divisible by the
840 * bulk-in maxpacket size.
842 bh->inreq->length = nread;
843 bh->state = BUF_STATE_FULL;
845 /* If an error occurred, report it and its position */
846 if (nread < amount) {
847 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
848 curlun->sense_data_info =
849 file_offset >> curlun->blkbits;
850 curlun->info_valid = 1;
854 if (amount_left == 0)
855 break; /* No more left to read */
857 /* Send this buffer and go read some more */
859 if (!start_in_transfer(common, bh))
860 /* Don't know what to do if common->fsg is NULL */
862 common->next_buffhd_to_fill = bh->next;
865 return -EIO; /* No default reply */
869 /*-------------------------------------------------------------------------*/
871 static int do_write(struct fsg_common *common)
873 struct fsg_lun *curlun = common->curlun;
875 struct fsg_buffhd *bh;
877 u32 amount_left_to_req, amount_left_to_write;
878 loff_t usb_offset, file_offset, file_offset_tmp;
884 curlun->sense_data = SS_WRITE_PROTECTED;
887 spin_lock(&curlun->filp->f_lock);
888 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
889 spin_unlock(&curlun->filp->f_lock);
892 * Get the starting Logical Block Address and check that it's
895 if (common->cmnd[0] == WRITE_6)
896 lba = get_unaligned_be24(&common->cmnd[1]);
898 lba = get_unaligned_be32(&common->cmnd[2]);
901 * We allow DPO (Disable Page Out = don't save data in the
902 * cache) and FUA (Force Unit Access = write directly to the
903 * medium). We don't implement DPO; we implement FUA by
904 * performing synchronous output.
906 if (common->cmnd[1] & ~0x18) {
907 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
910 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
911 spin_lock(&curlun->filp->f_lock);
912 curlun->filp->f_flags |= O_SYNC;
913 spin_unlock(&curlun->filp->f_lock);
916 if (lba >= curlun->num_sectors) {
917 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
921 /* Carry out the file writes */
923 file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
924 amount_left_to_req = common->data_size_from_cmnd;
925 amount_left_to_write = common->data_size_from_cmnd;
927 while (amount_left_to_write > 0) {
929 /* Queue a request for more data from the host */
930 bh = common->next_buffhd_to_fill;
931 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
934 * Figure out how much we want to get:
935 * Try to get the remaining amount,
936 * but not more than the buffer size.
938 amount = min(amount_left_to_req, FSG_BUFLEN);
940 /* Beyond the end of the backing file? */
941 if (usb_offset >= curlun->file_length) {
944 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
945 curlun->sense_data_info =
946 usb_offset >> curlun->blkbits;
947 curlun->info_valid = 1;
951 /* Get the next buffer */
952 usb_offset += amount;
953 common->usb_amount_left -= amount;
954 amount_left_to_req -= amount;
955 if (amount_left_to_req == 0)
959 * Except at the end of the transfer, amount will be
960 * equal to the buffer size, which is divisible by
961 * the bulk-out maxpacket size.
963 set_bulk_out_req_length(common, bh, amount);
964 if (!start_out_transfer(common, bh))
965 /* Dunno what to do if common->fsg is NULL */
967 common->next_buffhd_to_fill = bh->next;
971 /* Write the received data to the backing file */
972 bh = common->next_buffhd_to_drain;
973 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
974 break; /* We stopped early */
975 if (bh->state == BUF_STATE_FULL) {
977 common->next_buffhd_to_drain = bh->next;
978 bh->state = BUF_STATE_EMPTY;
980 /* Did something go wrong with the transfer? */
981 if (bh->outreq->status != 0) {
982 curlun->sense_data = SS_COMMUNICATION_FAILURE;
983 curlun->sense_data_info =
984 file_offset >> curlun->blkbits;
985 curlun->info_valid = 1;
989 amount = bh->outreq->actual;
990 if (curlun->file_length - file_offset < amount) {
992 "write %u @ %llu beyond end %llu\n",
993 amount, (unsigned long long)file_offset,
994 (unsigned long long)curlun->file_length);
995 amount = curlun->file_length - file_offset;
998 /* Don't accept excess data. The spec doesn't say
999 * what to do in this case. We'll ignore the error.
1001 amount = min(amount, bh->bulk_out_intended_length);
1003 /* Don't write a partial block */
1004 amount = round_down(amount, curlun->blksize);
1008 /* Perform the write */
1009 file_offset_tmp = file_offset;
1010 nwritten = vfs_write(curlun->filp,
1011 (char __user *)bh->buf,
1012 amount, &file_offset_tmp);
1013 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
1014 (unsigned long long)file_offset, (int)nwritten);
1015 if (signal_pending(current))
1016 return -EINTR; /* Interrupted! */
1019 LDBG(curlun, "error in file write: %d\n",
1022 } else if (nwritten < amount) {
1023 LDBG(curlun, "partial file write: %d/%u\n",
1024 (int)nwritten, amount);
1025 nwritten = round_down(nwritten, curlun->blksize);
1027 file_offset += nwritten;
1028 amount_left_to_write -= nwritten;
1029 common->residue -= nwritten;
1031 /* If an error occurred, report it and its position */
1032 if (nwritten < amount) {
1033 curlun->sense_data = SS_WRITE_ERROR;
1034 curlun->sense_data_info =
1035 file_offset >> curlun->blkbits;
1036 curlun->info_valid = 1;
1041 /* Did the host decide to stop early? */
1042 if (bh->outreq->actual < bh->bulk_out_intended_length) {
1043 common->short_packet_received = 1;
1049 /* Wait for something to happen */
1050 rc = sleep_thread(common);
1055 return -EIO; /* No default reply */
1059 /*-------------------------------------------------------------------------*/
1061 static int do_synchronize_cache(struct fsg_common *common)
1063 struct fsg_lun *curlun = common->curlun;
1066 /* We ignore the requested LBA and write out all file's
1067 * dirty data buffers. */
1068 rc = fsg_lun_fsync_sub(curlun);
1070 curlun->sense_data = SS_WRITE_ERROR;
1075 /*-------------------------------------------------------------------------*/
1077 static void invalidate_sub(struct fsg_lun *curlun)
1079 struct file *filp = curlun->filp;
1080 struct inode *inode = filp->f_path.dentry->d_inode;
1083 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
1084 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
1087 static int do_verify(struct fsg_common *common)
1089 struct fsg_lun *curlun = common->curlun;
1091 u32 verification_length;
1092 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1093 loff_t file_offset, file_offset_tmp;
1095 unsigned int amount;
1099 * Get the starting Logical Block Address and check that it's
1102 lba = get_unaligned_be32(&common->cmnd[2]);
1103 if (lba >= curlun->num_sectors) {
1104 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1109 * We allow DPO (Disable Page Out = don't save data in the
1110 * cache) but we don't implement it.
1112 if (common->cmnd[1] & ~0x10) {
1113 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1117 verification_length = get_unaligned_be16(&common->cmnd[7]);
1118 if (unlikely(verification_length == 0))
1119 return -EIO; /* No default reply */
1121 /* Prepare to carry out the file verify */
1122 amount_left = verification_length << curlun->blkbits;
1123 file_offset = ((loff_t) lba) << curlun->blkbits;
1125 /* Write out all the dirty buffers before invalidating them */
1126 fsg_lun_fsync_sub(curlun);
1127 if (signal_pending(current))
1130 invalidate_sub(curlun);
1131 if (signal_pending(current))
1134 /* Just try to read the requested blocks */
1135 while (amount_left > 0) {
1137 * Figure out how much we need to read:
1138 * Try to read the remaining amount, but not more than
1140 * And don't try to read past the end of the file.
1142 amount = min(amount_left, FSG_BUFLEN);
1143 amount = min((loff_t)amount,
1144 curlun->file_length - file_offset);
1146 curlun->sense_data =
1147 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1148 curlun->sense_data_info =
1149 file_offset >> curlun->blkbits;
1150 curlun->info_valid = 1;
1154 /* Perform the read */
1155 file_offset_tmp = file_offset;
1156 nread = vfs_read(curlun->filp,
1157 (char __user *) bh->buf,
1158 amount, &file_offset_tmp);
1159 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1160 (unsigned long long) file_offset,
1162 if (signal_pending(current))
1166 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1168 } else if (nread < amount) {
1169 LDBG(curlun, "partial file verify: %d/%u\n",
1170 (int)nread, amount);
1171 nread = round_down(nread, curlun->blksize);
1174 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1175 curlun->sense_data_info =
1176 file_offset >> curlun->blkbits;
1177 curlun->info_valid = 1;
1180 file_offset += nread;
1181 amount_left -= nread;
1187 /*-------------------------------------------------------------------------*/
1189 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1191 struct fsg_lun *curlun = common->curlun;
1192 u8 *buf = (u8 *) bh->buf;
1194 if (!curlun) { /* Unsupported LUNs are okay */
1195 common->bad_lun_okay = 1;
1197 buf[0] = 0x7f; /* Unsupported, no device-type */
1198 buf[4] = 31; /* Additional length */
1202 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1203 buf[1] = curlun->removable ? 0x80 : 0;
1204 buf[2] = 2; /* ANSI SCSI level 2 */
1205 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1206 buf[4] = 31; /* Additional length */
1207 buf[5] = 0; /* No special options */
1210 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1214 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1216 struct fsg_lun *curlun = common->curlun;
1217 u8 *buf = (u8 *) bh->buf;
1222 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1224 * If a REQUEST SENSE command is received from an initiator
1225 * with a pending unit attention condition (before the target
1226 * generates the contingent allegiance condition), then the
1227 * target shall either:
1228 * a) report any pending sense data and preserve the unit
1229 * attention condition on the logical unit, or,
1230 * b) report the unit attention condition, may discard any
1231 * pending sense data, and clear the unit attention
1232 * condition on the logical unit for that initiator.
1234 * FSG normally uses option a); enable this code to use option b).
1237 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1238 curlun->sense_data = curlun->unit_attention_data;
1239 curlun->unit_attention_data = SS_NO_SENSE;
1243 if (!curlun) { /* Unsupported LUNs are okay */
1244 common->bad_lun_okay = 1;
1245 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1249 sd = curlun->sense_data;
1250 sdinfo = curlun->sense_data_info;
1251 valid = curlun->info_valid << 7;
1252 curlun->sense_data = SS_NO_SENSE;
1253 curlun->sense_data_info = 0;
1254 curlun->info_valid = 0;
1258 buf[0] = valid | 0x70; /* Valid, current error */
1260 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1261 buf[7] = 18 - 8; /* Additional sense length */
1267 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1269 struct fsg_lun *curlun = common->curlun;
1270 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1271 int pmi = common->cmnd[8];
1272 u8 *buf = (u8 *)bh->buf;
1274 /* Check the PMI and LBA fields */
1275 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1276 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1280 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1281 /* Max logical block */
1282 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1286 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1288 struct fsg_lun *curlun = common->curlun;
1289 int msf = common->cmnd[1] & 0x02;
1290 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1291 u8 *buf = (u8 *)bh->buf;
1293 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1294 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1297 if (lba >= curlun->num_sectors) {
1298 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1303 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1304 store_cdrom_address(&buf[4], msf, lba);
1308 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1310 struct fsg_lun *curlun = common->curlun;
1311 int msf = common->cmnd[1] & 0x02;
1312 int start_track = common->cmnd[6];
1313 u8 *buf = (u8 *)bh->buf;
1315 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1317 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1322 buf[1] = (20-2); /* TOC data length */
1323 buf[2] = 1; /* First track number */
1324 buf[3] = 1; /* Last track number */
1325 buf[5] = 0x16; /* Data track, copying allowed */
1326 buf[6] = 0x01; /* Only track is number 1 */
1327 store_cdrom_address(&buf[8], msf, 0);
1329 buf[13] = 0x16; /* Lead-out track is data */
1330 buf[14] = 0xAA; /* Lead-out track number */
1331 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1335 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1337 struct fsg_lun *curlun = common->curlun;
1338 int mscmnd = common->cmnd[0];
1339 u8 *buf = (u8 *) bh->buf;
1342 int changeable_values, all_pages;
1346 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1347 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1350 pc = common->cmnd[2] >> 6;
1351 page_code = common->cmnd[2] & 0x3f;
1353 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1356 changeable_values = (pc == 1);
1357 all_pages = (page_code == 0x3f);
1360 * Write the mode parameter header. Fixed values are: default
1361 * medium type, no cache control (DPOFUA), and no block descriptors.
1362 * The only variable value is the WriteProtect bit. We will fill in
1363 * the mode data length later.
1366 if (mscmnd == MODE_SENSE) {
1367 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1370 } else { /* MODE_SENSE_10 */
1371 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1373 limit = 65535; /* Should really be FSG_BUFLEN */
1376 /* No block descriptors */
1379 * The mode pages, in numerical order. The only page we support
1380 * is the Caching page.
1382 if (page_code == 0x08 || all_pages) {
1384 buf[0] = 0x08; /* Page code */
1385 buf[1] = 10; /* Page length */
1386 memset(buf+2, 0, 10); /* None of the fields are changeable */
1388 if (!changeable_values) {
1389 buf[2] = 0x04; /* Write cache enable, */
1390 /* Read cache not disabled */
1391 /* No cache retention priorities */
1392 put_unaligned_be16(0xffff, &buf[4]);
1393 /* Don't disable prefetch */
1394 /* Minimum prefetch = 0 */
1395 put_unaligned_be16(0xffff, &buf[8]);
1396 /* Maximum prefetch */
1397 put_unaligned_be16(0xffff, &buf[10]);
1398 /* Maximum prefetch ceiling */
1404 * Check that a valid page was requested and the mode data length
1408 if (!valid_page || len > limit) {
1409 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1413 /* Store the mode data length */
1414 if (mscmnd == MODE_SENSE)
1417 put_unaligned_be16(len - 2, buf0);
1421 static int do_start_stop(struct fsg_common *common)
1423 struct fsg_lun *curlun = common->curlun;
1428 } else if (!curlun->removable) {
1429 curlun->sense_data = SS_INVALID_COMMAND;
1431 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1432 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1433 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1437 loej = common->cmnd[4] & 0x02;
1438 start = common->cmnd[4] & 0x01;
1441 * Our emulation doesn't support mounting; the medium is
1442 * available for use as soon as it is loaded.
1445 if (!fsg_lun_is_open(curlun)) {
1446 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1452 /* Are we allowed to unload the media? */
1453 if (curlun->prevent_medium_removal) {
1454 LDBG(curlun, "unload attempt prevented\n");
1455 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1462 /* Simulate an unload/eject */
1463 if (common->ops && common->ops->pre_eject) {
1464 int r = common->ops->pre_eject(common, curlun,
1465 curlun - common->luns);
1466 if (unlikely(r < 0))
1472 up_read(&common->filesem);
1473 down_write(&common->filesem);
1474 fsg_lun_close(curlun);
1475 up_write(&common->filesem);
1476 down_read(&common->filesem);
1478 return common->ops && common->ops->post_eject
1479 ? min(0, common->ops->post_eject(common, curlun,
1480 curlun - common->luns))
1484 static int do_prevent_allow(struct fsg_common *common)
1486 struct fsg_lun *curlun = common->curlun;
1489 if (!common->curlun) {
1491 } else if (!common->curlun->removable) {
1492 common->curlun->sense_data = SS_INVALID_COMMAND;
1496 prevent = common->cmnd[4] & 0x01;
1497 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1498 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1502 if (curlun->prevent_medium_removal && !prevent)
1503 fsg_lun_fsync_sub(curlun);
1504 curlun->prevent_medium_removal = prevent;
1508 static int do_read_format_capacities(struct fsg_common *common,
1509 struct fsg_buffhd *bh)
1511 struct fsg_lun *curlun = common->curlun;
1512 u8 *buf = (u8 *) bh->buf;
1514 buf[0] = buf[1] = buf[2] = 0;
1515 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1518 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1519 /* Number of blocks */
1520 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1521 buf[4] = 0x02; /* Current capacity */
1525 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1527 struct fsg_lun *curlun = common->curlun;
1529 /* We don't support MODE SELECT */
1531 curlun->sense_data = SS_INVALID_COMMAND;
1536 /*-------------------------------------------------------------------------*/
1538 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1542 rc = fsg_set_halt(fsg, fsg->bulk_in);
1544 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1546 if (rc != -EAGAIN) {
1547 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1552 /* Wait for a short time and then try again */
1553 if (msleep_interruptible(100) != 0)
1555 rc = usb_ep_set_halt(fsg->bulk_in);
1560 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1564 DBG(fsg, "bulk-in set wedge\n");
1565 rc = usb_ep_set_wedge(fsg->bulk_in);
1567 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1569 if (rc != -EAGAIN) {
1570 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1575 /* Wait for a short time and then try again */
1576 if (msleep_interruptible(100) != 0)
1578 rc = usb_ep_set_wedge(fsg->bulk_in);
1583 static int throw_away_data(struct fsg_common *common)
1585 struct fsg_buffhd *bh;
1589 for (bh = common->next_buffhd_to_drain;
1590 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1591 bh = common->next_buffhd_to_drain) {
1593 /* Throw away the data in a filled buffer */
1594 if (bh->state == BUF_STATE_FULL) {
1596 bh->state = BUF_STATE_EMPTY;
1597 common->next_buffhd_to_drain = bh->next;
1599 /* A short packet or an error ends everything */
1600 if (bh->outreq->actual < bh->bulk_out_intended_length ||
1601 bh->outreq->status != 0) {
1602 raise_exception(common,
1603 FSG_STATE_ABORT_BULK_OUT);
1609 /* Try to submit another request if we need one */
1610 bh = common->next_buffhd_to_fill;
1611 if (bh->state == BUF_STATE_EMPTY
1612 && common->usb_amount_left > 0) {
1613 amount = min(common->usb_amount_left, FSG_BUFLEN);
1616 * Except at the end of the transfer, amount will be
1617 * equal to the buffer size, which is divisible by
1618 * the bulk-out maxpacket size.
1620 set_bulk_out_req_length(common, bh, amount);
1621 if (!start_out_transfer(common, bh))
1622 /* Dunno what to do if common->fsg is NULL */
1624 common->next_buffhd_to_fill = bh->next;
1625 common->usb_amount_left -= amount;
1629 /* Otherwise wait for something to happen */
1630 rc = sleep_thread(common);
1637 static int finish_reply(struct fsg_common *common)
1639 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1642 switch (common->data_dir) {
1644 break; /* Nothing to send */
1647 * If we don't know whether the host wants to read or write,
1648 * this must be CB or CBI with an unknown command. We mustn't
1649 * try to send or receive any data. So stall both bulk pipes
1650 * if we can and wait for a reset.
1652 case DATA_DIR_UNKNOWN:
1653 if (!common->can_stall) {
1655 } else if (fsg_is_set(common)) {
1656 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1657 rc = halt_bulk_in_endpoint(common->fsg);
1659 /* Don't know what to do if common->fsg is NULL */
1664 /* All but the last buffer of data must have already been sent */
1665 case DATA_DIR_TO_HOST:
1666 if (common->data_size == 0) {
1667 /* Nothing to send */
1669 /* Don't know what to do if common->fsg is NULL */
1670 } else if (!fsg_is_set(common)) {
1673 /* If there's no residue, simply send the last buffer */
1674 } else if (common->residue == 0) {
1675 bh->inreq->zero = 0;
1676 if (!start_in_transfer(common, bh))
1678 common->next_buffhd_to_fill = bh->next;
1681 * For Bulk-only, mark the end of the data with a short
1682 * packet. If we are allowed to stall, halt the bulk-in
1683 * endpoint. (Note: This violates the Bulk-Only Transport
1684 * specification, which requires us to pad the data if we
1685 * don't halt the endpoint. Presumably nobody will mind.)
1688 bh->inreq->zero = 1;
1689 if (!start_in_transfer(common, bh))
1691 common->next_buffhd_to_fill = bh->next;
1692 if (common->can_stall)
1693 rc = halt_bulk_in_endpoint(common->fsg);
1698 * We have processed all we want from the data the host has sent.
1699 * There may still be outstanding bulk-out requests.
1701 case DATA_DIR_FROM_HOST:
1702 if (common->residue == 0) {
1703 /* Nothing to receive */
1705 /* Did the host stop sending unexpectedly early? */
1706 } else if (common->short_packet_received) {
1707 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1711 * We haven't processed all the incoming data. Even though
1712 * we may be allowed to stall, doing so would cause a race.
1713 * The controller may already have ACK'ed all the remaining
1714 * bulk-out packets, in which case the host wouldn't see a
1715 * STALL. Not realizing the endpoint was halted, it wouldn't
1716 * clear the halt -- leading to problems later on.
1719 } else if (common->can_stall) {
1720 if (fsg_is_set(common))
1721 fsg_set_halt(common->fsg,
1722 common->fsg->bulk_out);
1723 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1728 * We can't stall. Read in the excess data and throw it
1732 rc = throw_away_data(common);
1739 static int send_status(struct fsg_common *common)
1741 struct fsg_lun *curlun = common->curlun;
1742 struct fsg_buffhd *bh;
1743 struct bulk_cs_wrap *csw;
1745 u8 status = USB_STATUS_PASS;
1748 /* Wait for the next buffer to become available */
1749 bh = common->next_buffhd_to_fill;
1750 while (bh->state != BUF_STATE_EMPTY) {
1751 rc = sleep_thread(common);
1757 sd = curlun->sense_data;
1758 sdinfo = curlun->sense_data_info;
1759 } else if (common->bad_lun_okay)
1762 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1764 if (common->phase_error) {
1765 DBG(common, "sending phase-error status\n");
1766 status = USB_STATUS_PHASE_ERROR;
1767 sd = SS_INVALID_COMMAND;
1768 } else if (sd != SS_NO_SENSE) {
1769 DBG(common, "sending command-failure status\n");
1770 status = USB_STATUS_FAIL;
1771 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1773 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1776 /* Store and send the Bulk-only CSW */
1777 csw = (void *)bh->buf;
1779 csw->Signature = cpu_to_le32(USB_BULK_CS_SIG);
1780 csw->Tag = common->tag;
1781 csw->Residue = cpu_to_le32(common->residue);
1782 csw->Status = status;
1784 bh->inreq->length = USB_BULK_CS_WRAP_LEN;
1785 bh->inreq->zero = 0;
1786 if (!start_in_transfer(common, bh))
1787 /* Don't know what to do if common->fsg is NULL */
1790 common->next_buffhd_to_fill = bh->next;
1795 /*-------------------------------------------------------------------------*/
1798 * Check whether the command is properly formed and whether its data size
1799 * and direction agree with the values we already have.
1801 static int check_command(struct fsg_common *common, int cmnd_size,
1802 enum data_direction data_dir, unsigned int mask,
1803 int needs_medium, const char *name)
1806 int lun = common->cmnd[1] >> 5;
1807 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1809 struct fsg_lun *curlun;
1812 if (common->data_dir != DATA_DIR_UNKNOWN)
1813 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1815 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1816 name, cmnd_size, dirletter[(int) data_dir],
1817 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1820 * We can't reply at all until we know the correct data direction
1823 if (common->data_size_from_cmnd == 0)
1824 data_dir = DATA_DIR_NONE;
1825 if (common->data_size < common->data_size_from_cmnd) {
1827 * Host data size < Device data size is a phase error.
1828 * Carry out the command, but only transfer as much as
1831 common->data_size_from_cmnd = common->data_size;
1832 common->phase_error = 1;
1834 common->residue = common->data_size;
1835 common->usb_amount_left = common->data_size;
1837 /* Conflicting data directions is a phase error */
1838 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1839 common->phase_error = 1;
1843 /* Verify the length of the command itself */
1844 if (cmnd_size != common->cmnd_size) {
1847 * Special case workaround: There are plenty of buggy SCSI
1848 * implementations. Many have issues with cbw->Length
1849 * field passing a wrong command size. For those cases we
1850 * always try to work around the problem by using the length
1851 * sent by the host side provided it is at least as large
1852 * as the correct command length.
1853 * Examples of such cases would be MS-Windows, which issues
1854 * REQUEST SENSE with cbw->Length == 12 where it should
1855 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1856 * REQUEST SENSE with cbw->Length == 10 where it should
1859 if (cmnd_size <= common->cmnd_size) {
1860 DBG(common, "%s is buggy! Expected length %d "
1861 "but we got %d\n", name,
1862 cmnd_size, common->cmnd_size);
1863 cmnd_size = common->cmnd_size;
1865 common->phase_error = 1;
1870 /* Check that the LUN values are consistent */
1871 if (common->lun != lun)
1872 DBG(common, "using LUN %d from CBW, not LUN %d from CDB\n",
1876 if (common->lun < common->nluns) {
1877 curlun = &common->luns[common->lun];
1878 common->curlun = curlun;
1879 if (common->cmnd[0] != REQUEST_SENSE) {
1880 curlun->sense_data = SS_NO_SENSE;
1881 curlun->sense_data_info = 0;
1882 curlun->info_valid = 0;
1885 common->curlun = NULL;
1887 common->bad_lun_okay = 0;
1890 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1891 * to use unsupported LUNs; all others may not.
1893 if (common->cmnd[0] != INQUIRY &&
1894 common->cmnd[0] != REQUEST_SENSE) {
1895 DBG(common, "unsupported LUN %d\n", common->lun);
1901 * If a unit attention condition exists, only INQUIRY and
1902 * REQUEST SENSE commands are allowed; anything else must fail.
1904 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1905 common->cmnd[0] != INQUIRY &&
1906 common->cmnd[0] != REQUEST_SENSE) {
1907 curlun->sense_data = curlun->unit_attention_data;
1908 curlun->unit_attention_data = SS_NO_SENSE;
1912 /* Check that only command bytes listed in the mask are non-zero */
1913 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1914 for (i = 1; i < cmnd_size; ++i) {
1915 if (common->cmnd[i] && !(mask & (1 << i))) {
1917 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1922 /* If the medium isn't mounted and the command needs to access
1923 * it, return an error. */
1924 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1925 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1932 static int do_scsi_command(struct fsg_common *common)
1934 struct fsg_buffhd *bh;
1936 int reply = -EINVAL;
1938 static char unknown[16];
1942 /* Wait for the next buffer to become available for data or status */
1943 bh = common->next_buffhd_to_fill;
1944 common->next_buffhd_to_drain = bh;
1945 while (bh->state != BUF_STATE_EMPTY) {
1946 rc = sleep_thread(common);
1950 common->phase_error = 0;
1951 common->short_packet_received = 0;
1953 down_read(&common->filesem); /* We're using the backing file */
1954 switch (common->cmnd[0]) {
1957 common->data_size_from_cmnd = common->cmnd[4];
1958 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1962 reply = do_inquiry(common, bh);
1966 common->data_size_from_cmnd = common->cmnd[4];
1967 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1971 reply = do_mode_select(common, bh);
1974 case MODE_SELECT_10:
1975 common->data_size_from_cmnd =
1976 get_unaligned_be16(&common->cmnd[7]);
1977 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1981 reply = do_mode_select(common, bh);
1985 common->data_size_from_cmnd = common->cmnd[4];
1986 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1987 (1<<1) | (1<<2) | (1<<4), 0,
1990 reply = do_mode_sense(common, bh);
1994 common->data_size_from_cmnd =
1995 get_unaligned_be16(&common->cmnd[7]);
1996 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1997 (1<<1) | (1<<2) | (3<<7), 0,
2000 reply = do_mode_sense(common, bh);
2003 case ALLOW_MEDIUM_REMOVAL:
2004 common->data_size_from_cmnd = 0;
2005 reply = check_command(common, 6, DATA_DIR_NONE,
2007 "PREVENT-ALLOW MEDIUM REMOVAL");
2009 reply = do_prevent_allow(common);
2013 i = common->cmnd[4];
2014 common->data_size_from_cmnd = (i == 0 ? 256 : i) <<
2015 common->curlun->blkbits;
2016 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2020 reply = do_read(common);
2024 common->data_size_from_cmnd =
2025 get_unaligned_be16(&common->cmnd[7]) <<
2026 common->curlun->blkbits;
2027 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2028 (1<<1) | (0xf<<2) | (3<<7), 1,
2031 reply = do_read(common);
2035 common->data_size_from_cmnd =
2036 get_unaligned_be32(&common->cmnd[6]) <<
2037 common->curlun->blkbits;
2038 reply = check_command(common, 12, DATA_DIR_TO_HOST,
2039 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2042 reply = do_read(common);
2046 common->data_size_from_cmnd = 8;
2047 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2048 (0xf<<2) | (1<<8), 1,
2051 reply = do_read_capacity(common, bh);
2055 if (!common->curlun || !common->curlun->cdrom)
2057 common->data_size_from_cmnd =
2058 get_unaligned_be16(&common->cmnd[7]);
2059 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2060 (3<<7) | (0x1f<<1), 1,
2063 reply = do_read_header(common, bh);
2067 if (!common->curlun || !common->curlun->cdrom)
2069 common->data_size_from_cmnd =
2070 get_unaligned_be16(&common->cmnd[7]);
2071 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2075 reply = do_read_toc(common, bh);
2078 case READ_FORMAT_CAPACITIES:
2079 common->data_size_from_cmnd =
2080 get_unaligned_be16(&common->cmnd[7]);
2081 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2083 "READ FORMAT CAPACITIES");
2085 reply = do_read_format_capacities(common, bh);
2089 common->data_size_from_cmnd = common->cmnd[4];
2090 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2094 reply = do_request_sense(common, bh);
2098 common->data_size_from_cmnd = 0;
2099 reply = check_command(common, 6, DATA_DIR_NONE,
2103 reply = do_start_stop(common);
2106 case SYNCHRONIZE_CACHE:
2107 common->data_size_from_cmnd = 0;
2108 reply = check_command(common, 10, DATA_DIR_NONE,
2109 (0xf<<2) | (3<<7), 1,
2110 "SYNCHRONIZE CACHE");
2112 reply = do_synchronize_cache(common);
2115 case TEST_UNIT_READY:
2116 common->data_size_from_cmnd = 0;
2117 reply = check_command(common, 6, DATA_DIR_NONE,
2123 * Although optional, this command is used by MS-Windows. We
2124 * support a minimal version: BytChk must be 0.
2127 common->data_size_from_cmnd = 0;
2128 reply = check_command(common, 10, DATA_DIR_NONE,
2129 (1<<1) | (0xf<<2) | (3<<7), 1,
2132 reply = do_verify(common);
2136 i = common->cmnd[4];
2137 common->data_size_from_cmnd = (i == 0 ? 256 : i) <<
2138 common->curlun->blkbits;
2139 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
2143 reply = do_write(common);
2147 common->data_size_from_cmnd =
2148 get_unaligned_be16(&common->cmnd[7]) <<
2149 common->curlun->blkbits;
2150 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
2151 (1<<1) | (0xf<<2) | (3<<7), 1,
2154 reply = do_write(common);
2158 common->data_size_from_cmnd =
2159 get_unaligned_be32(&common->cmnd[6]) <<
2160 common->curlun->blkbits;
2161 reply = check_command(common, 12, DATA_DIR_FROM_HOST,
2162 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2165 reply = do_write(common);
2169 * Some mandatory commands that we recognize but don't implement.
2170 * They don't mean much in this setting. It's left as an exercise
2171 * for anyone interested to implement RESERVE and RELEASE in terms
2177 case SEND_DIAGNOSTIC:
2182 common->data_size_from_cmnd = 0;
2183 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2184 reply = check_command(common, common->cmnd_size,
2185 DATA_DIR_UNKNOWN, 0xff, 0, unknown);
2187 common->curlun->sense_data = SS_INVALID_COMMAND;
2192 up_read(&common->filesem);
2194 if (reply == -EINTR || signal_pending(current))
2197 /* Set up the single reply buffer for finish_reply() */
2198 if (reply == -EINVAL)
2199 reply = 0; /* Error reply length */
2200 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2201 reply = min((u32)reply, common->data_size_from_cmnd);
2202 bh->inreq->length = reply;
2203 bh->state = BUF_STATE_FULL;
2204 common->residue -= reply;
2205 } /* Otherwise it's already set */
2211 /*-------------------------------------------------------------------------*/
2213 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2215 struct usb_request *req = bh->outreq;
2216 struct fsg_bulk_cb_wrap *cbw = req->buf;
2217 struct fsg_common *common = fsg->common;
2219 /* Was this a real packet? Should it be ignored? */
2220 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2223 /* Is the CBW valid? */
2224 if (req->actual != USB_BULK_CB_WRAP_LEN ||
2225 cbw->Signature != cpu_to_le32(
2227 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2229 le32_to_cpu(cbw->Signature));
2232 * The Bulk-only spec says we MUST stall the IN endpoint
2233 * (6.6.1), so it's unavoidable. It also says we must
2234 * retain this state until the next reset, but there's
2235 * no way to tell the controller driver it should ignore
2236 * Clear-Feature(HALT) requests.
2238 * We aren't required to halt the OUT endpoint; instead
2239 * we can simply accept and discard any data received
2240 * until the next reset.
2242 wedge_bulk_in_endpoint(fsg);
2243 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2247 /* Is the CBW meaningful? */
2248 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG ||
2249 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2250 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2252 cbw->Lun, cbw->Flags, cbw->Length);
2255 * We can do anything we want here, so let's stall the
2256 * bulk pipes if we are allowed to.
2258 if (common->can_stall) {
2259 fsg_set_halt(fsg, fsg->bulk_out);
2260 halt_bulk_in_endpoint(fsg);
2265 /* Save the command for later */
2266 common->cmnd_size = cbw->Length;
2267 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2268 if (cbw->Flags & USB_BULK_IN_FLAG)
2269 common->data_dir = DATA_DIR_TO_HOST;
2271 common->data_dir = DATA_DIR_FROM_HOST;
2272 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2273 if (common->data_size == 0)
2274 common->data_dir = DATA_DIR_NONE;
2275 common->lun = cbw->Lun;
2276 common->tag = cbw->Tag;
2280 static int get_next_command(struct fsg_common *common)
2282 struct fsg_buffhd *bh;
2285 /* Wait for the next buffer to become available */
2286 bh = common->next_buffhd_to_fill;
2287 while (bh->state != BUF_STATE_EMPTY) {
2288 rc = sleep_thread(common);
2293 /* Queue a request to read a Bulk-only CBW */
2294 set_bulk_out_req_length(common, bh, USB_BULK_CB_WRAP_LEN);
2295 if (!start_out_transfer(common, bh))
2296 /* Don't know what to do if common->fsg is NULL */
2300 * We will drain the buffer in software, which means we
2301 * can reuse it for the next filling. No need to advance
2302 * next_buffhd_to_fill.
2305 /* Wait for the CBW to arrive */
2306 while (bh->state != BUF_STATE_FULL) {
2307 rc = sleep_thread(common);
2312 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2313 bh->state = BUF_STATE_EMPTY;
2319 /*-------------------------------------------------------------------------*/
2321 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2322 struct usb_request **preq)
2324 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2327 ERROR(common, "can't allocate request for %s\n", ep->name);
2331 /* Reset interface setting and re-init endpoint state (toggle etc). */
2332 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2334 struct fsg_dev *fsg;
2337 if (common->running)
2338 DBG(common, "reset interface\n");
2341 /* Deallocate the requests */
2345 for (i = 0; i < fsg_num_buffers; ++i) {
2346 struct fsg_buffhd *bh = &common->buffhds[i];
2349 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2353 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2358 /* Disable the endpoints */
2359 if (fsg->bulk_in_enabled) {
2360 usb_ep_disable(fsg->bulk_in);
2361 fsg->bulk_in_enabled = 0;
2363 if (fsg->bulk_out_enabled) {
2364 usb_ep_disable(fsg->bulk_out);
2365 fsg->bulk_out_enabled = 0;
2369 wake_up(&common->fsg_wait);
2372 common->running = 0;
2376 common->fsg = new_fsg;
2379 /* Enable the endpoints */
2380 rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
2383 rc = usb_ep_enable(fsg->bulk_in);
2386 fsg->bulk_in->driver_data = common;
2387 fsg->bulk_in_enabled = 1;
2389 rc = config_ep_by_speed(common->gadget, &(fsg->function),
2393 rc = usb_ep_enable(fsg->bulk_out);
2396 fsg->bulk_out->driver_data = common;
2397 fsg->bulk_out_enabled = 1;
2398 common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc);
2399 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2401 /* Allocate the requests */
2402 for (i = 0; i < fsg_num_buffers; ++i) {
2403 struct fsg_buffhd *bh = &common->buffhds[i];
2405 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2408 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2411 bh->inreq->buf = bh->outreq->buf = bh->buf;
2412 bh->inreq->context = bh->outreq->context = bh;
2413 bh->inreq->complete = bulk_in_complete;
2414 bh->outreq->complete = bulk_out_complete;
2417 common->running = 1;
2418 for (i = 0; i < common->nluns; ++i)
2419 common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
2424 /****************************** ALT CONFIGS ******************************/
2426 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2428 struct fsg_dev *fsg = fsg_from_func(f);
2429 fsg->common->new_fsg = fsg;
2430 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2431 return USB_GADGET_DELAYED_STATUS;
2434 static void fsg_disable(struct usb_function *f)
2436 struct fsg_dev *fsg = fsg_from_func(f);
2437 fsg->common->new_fsg = NULL;
2438 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2442 /*-------------------------------------------------------------------------*/
2444 static void handle_exception(struct fsg_common *common)
2448 struct fsg_buffhd *bh;
2449 enum fsg_state old_state;
2450 struct fsg_lun *curlun;
2451 unsigned int exception_req_tag;
2454 * Clear the existing signals. Anything but SIGUSR1 is converted
2455 * into a high-priority EXIT exception.
2459 dequeue_signal_lock(current, ¤t->blocked, &info);
2462 if (sig != SIGUSR1) {
2463 if (common->state < FSG_STATE_EXIT)
2464 DBG(common, "Main thread exiting on signal\n");
2465 raise_exception(common, FSG_STATE_EXIT);
2469 /* Cancel all the pending transfers */
2470 if (likely(common->fsg)) {
2471 for (i = 0; i < fsg_num_buffers; ++i) {
2472 bh = &common->buffhds[i];
2474 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2475 if (bh->outreq_busy)
2476 usb_ep_dequeue(common->fsg->bulk_out,
2480 /* Wait until everything is idle */
2483 for (i = 0; i < fsg_num_buffers; ++i) {
2484 bh = &common->buffhds[i];
2485 num_active += bh->inreq_busy + bh->outreq_busy;
2487 if (num_active == 0)
2489 if (sleep_thread(common))
2493 /* Clear out the controller's fifos */
2494 if (common->fsg->bulk_in_enabled)
2495 usb_ep_fifo_flush(common->fsg->bulk_in);
2496 if (common->fsg->bulk_out_enabled)
2497 usb_ep_fifo_flush(common->fsg->bulk_out);
2501 * Reset the I/O buffer states and pointers, the SCSI
2502 * state, and the exception. Then invoke the handler.
2504 spin_lock_irq(&common->lock);
2506 for (i = 0; i < fsg_num_buffers; ++i) {
2507 bh = &common->buffhds[i];
2508 bh->state = BUF_STATE_EMPTY;
2510 common->next_buffhd_to_fill = &common->buffhds[0];
2511 common->next_buffhd_to_drain = &common->buffhds[0];
2512 exception_req_tag = common->exception_req_tag;
2513 old_state = common->state;
2515 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2516 common->state = FSG_STATE_STATUS_PHASE;
2518 for (i = 0; i < common->nluns; ++i) {
2519 curlun = &common->luns[i];
2520 curlun->prevent_medium_removal = 0;
2521 curlun->sense_data = SS_NO_SENSE;
2522 curlun->unit_attention_data = SS_NO_SENSE;
2523 curlun->sense_data_info = 0;
2524 curlun->info_valid = 0;
2526 common->state = FSG_STATE_IDLE;
2528 spin_unlock_irq(&common->lock);
2530 /* Carry out any extra actions required for the exception */
2531 switch (old_state) {
2532 case FSG_STATE_ABORT_BULK_OUT:
2533 send_status(common);
2534 spin_lock_irq(&common->lock);
2535 if (common->state == FSG_STATE_STATUS_PHASE)
2536 common->state = FSG_STATE_IDLE;
2537 spin_unlock_irq(&common->lock);
2540 case FSG_STATE_RESET:
2542 * In case we were forced against our will to halt a
2543 * bulk endpoint, clear the halt now. (The SuperH UDC
2546 if (!fsg_is_set(common))
2548 if (test_and_clear_bit(IGNORE_BULK_OUT,
2549 &common->fsg->atomic_bitflags))
2550 usb_ep_clear_halt(common->fsg->bulk_in);
2552 if (common->ep0_req_tag == exception_req_tag)
2553 ep0_queue(common); /* Complete the status stage */
2556 * Technically this should go here, but it would only be
2557 * a waste of time. Ditto for the INTERFACE_CHANGE and
2558 * CONFIG_CHANGE cases.
2560 /* for (i = 0; i < common->nluns; ++i) */
2561 /* common->luns[i].unit_attention_data = */
2562 /* SS_RESET_OCCURRED; */
2565 case FSG_STATE_CONFIG_CHANGE:
2566 do_set_interface(common, common->new_fsg);
2567 if (common->new_fsg)
2568 usb_composite_setup_continue(common->cdev);
2571 case FSG_STATE_EXIT:
2572 case FSG_STATE_TERMINATED:
2573 do_set_interface(common, NULL); /* Free resources */
2574 spin_lock_irq(&common->lock);
2575 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2576 spin_unlock_irq(&common->lock);
2579 case FSG_STATE_INTERFACE_CHANGE:
2580 case FSG_STATE_DISCONNECT:
2581 case FSG_STATE_COMMAND_PHASE:
2582 case FSG_STATE_DATA_PHASE:
2583 case FSG_STATE_STATUS_PHASE:
2584 case FSG_STATE_IDLE:
2590 /*-------------------------------------------------------------------------*/
2592 static int fsg_main_thread(void *common_)
2594 struct fsg_common *common = common_;
2597 * Allow the thread to be killed by a signal, but set the signal mask
2598 * to block everything but INT, TERM, KILL, and USR1.
2600 allow_signal(SIGINT);
2601 allow_signal(SIGTERM);
2602 allow_signal(SIGKILL);
2603 allow_signal(SIGUSR1);
2605 /* Allow the thread to be frozen */
2609 * Arrange for userspace references to be interpreted as kernel
2610 * pointers. That way we can pass a kernel pointer to a routine
2611 * that expects a __user pointer and it will work okay.
2616 while (common->state != FSG_STATE_TERMINATED) {
2617 if (exception_in_progress(common) || signal_pending(current)) {
2618 handle_exception(common);
2622 if (!common->running) {
2623 sleep_thread(common);
2627 if (get_next_command(common))
2630 spin_lock_irq(&common->lock);
2631 if (!exception_in_progress(common))
2632 common->state = FSG_STATE_DATA_PHASE;
2633 spin_unlock_irq(&common->lock);
2635 if (do_scsi_command(common) || finish_reply(common))
2638 spin_lock_irq(&common->lock);
2639 if (!exception_in_progress(common))
2640 common->state = FSG_STATE_STATUS_PHASE;
2641 spin_unlock_irq(&common->lock);
2643 if (send_status(common))
2646 spin_lock_irq(&common->lock);
2647 if (!exception_in_progress(common))
2648 common->state = FSG_STATE_IDLE;
2649 spin_unlock_irq(&common->lock);
2652 spin_lock_irq(&common->lock);
2653 common->thread_task = NULL;
2654 spin_unlock_irq(&common->lock);
2656 if (!common->ops || !common->ops->thread_exits
2657 || common->ops->thread_exits(common) < 0) {
2658 struct fsg_lun *curlun = common->luns;
2659 unsigned i = common->nluns;
2661 down_write(&common->filesem);
2662 for (; i--; ++curlun) {
2663 if (!fsg_lun_is_open(curlun))
2666 fsg_lun_close(curlun);
2667 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
2669 up_write(&common->filesem);
2672 /* Let fsg_unbind() know the thread has exited */
2673 complete_and_exit(&common->thread_notifier, 0);
2677 /*************************** DEVICE ATTRIBUTES ***************************/
2679 /* Write permission is checked per LUN in store_*() functions. */
2680 static DEVICE_ATTR(ro, 0644, fsg_show_ro, fsg_store_ro);
2681 static DEVICE_ATTR(nofua, 0644, fsg_show_nofua, fsg_store_nofua);
2682 static DEVICE_ATTR(file, 0644, fsg_show_file, fsg_store_file);
2685 /****************************** FSG COMMON ******************************/
2687 static void fsg_common_release(struct kref *ref);
2689 static void fsg_lun_release(struct device *dev)
2691 /* Nothing needs to be done */
2694 static inline void fsg_common_get(struct fsg_common *common)
2696 kref_get(&common->ref);
2699 static inline void fsg_common_put(struct fsg_common *common)
2701 kref_put(&common->ref, fsg_common_release);
2704 static struct fsg_common *fsg_common_init(struct fsg_common *common,
2705 struct usb_composite_dev *cdev,
2706 struct fsg_config *cfg)
2708 struct usb_gadget *gadget = cdev->gadget;
2709 struct fsg_buffhd *bh;
2710 struct fsg_lun *curlun;
2711 struct fsg_lun_config *lcfg;
2715 rc = fsg_num_buffers_validate();
2719 /* Find out how many LUNs there should be */
2721 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2722 dev_err(&gadget->dev, "invalid number of LUNs: %u\n", nluns);
2723 return ERR_PTR(-EINVAL);
2728 common = kzalloc(sizeof *common, GFP_KERNEL);
2730 return ERR_PTR(-ENOMEM);
2731 common->free_storage_on_release = 1;
2733 memset(common, 0, sizeof *common);
2734 common->free_storage_on_release = 0;
2737 common->buffhds = kcalloc(fsg_num_buffers,
2738 sizeof *(common->buffhds), GFP_KERNEL);
2739 if (!common->buffhds) {
2740 if (common->free_storage_on_release)
2742 return ERR_PTR(-ENOMEM);
2745 common->ops = cfg->ops;
2746 common->private_data = cfg->private_data;
2748 common->gadget = gadget;
2749 common->ep0 = gadget->ep0;
2750 common->ep0req = cdev->req;
2751 common->cdev = cdev;
2753 /* Maybe allocate device-global string IDs, and patch descriptors */
2754 if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
2755 rc = usb_string_id(cdev);
2756 if (unlikely(rc < 0))
2758 fsg_strings[FSG_STRING_INTERFACE].id = rc;
2759 fsg_intf_desc.iInterface = rc;
2763 * Create the LUNs, open their backing files, and register the
2764 * LUN devices in sysfs.
2766 curlun = kzalloc(nluns * sizeof *curlun, GFP_KERNEL);
2767 if (unlikely(!curlun)) {
2771 common->luns = curlun;
2773 init_rwsem(&common->filesem);
2775 for (i = 0, lcfg = cfg->luns; i < nluns; ++i, ++curlun, ++lcfg) {
2776 curlun->cdrom = !!lcfg->cdrom;
2777 curlun->ro = lcfg->cdrom || lcfg->ro;
2778 curlun->initially_ro = curlun->ro;
2779 curlun->removable = lcfg->removable;
2780 curlun->dev.release = fsg_lun_release;
2781 curlun->dev.parent = &gadget->dev;
2782 /* curlun->dev.driver = &fsg_driver.driver; XXX */
2783 dev_set_drvdata(&curlun->dev, &common->filesem);
2784 dev_set_name(&curlun->dev,
2785 cfg->lun_name_format
2786 ? cfg->lun_name_format
2790 rc = device_register(&curlun->dev);
2792 INFO(common, "failed to register LUN%d: %d\n", i, rc);
2794 put_device(&curlun->dev);
2798 rc = device_create_file(&curlun->dev, &dev_attr_ro);
2801 rc = device_create_file(&curlun->dev, &dev_attr_file);
2804 rc = device_create_file(&curlun->dev, &dev_attr_nofua);
2808 if (lcfg->filename) {
2809 rc = fsg_lun_open(curlun, lcfg->filename);
2812 } else if (!curlun->removable) {
2813 ERROR(common, "no file given for LUN%d\n", i);
2818 common->nluns = nluns;
2820 /* Data buffers cyclic list */
2821 bh = common->buffhds;
2822 i = fsg_num_buffers;
2823 goto buffhds_first_it;
2828 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2829 if (unlikely(!bh->buf)) {
2834 bh->next = common->buffhds;
2836 /* Prepare inquiryString */
2837 if (cfg->release != 0xffff) {
2840 i = usb_gadget_controller_number(gadget);
2844 WARNING(common, "controller '%s' not recognized\n",
2849 snprintf(common->inquiry_string, sizeof common->inquiry_string,
2850 "%-8s%-16s%04x", cfg->vendor_name ?: "Linux",
2851 /* Assume product name dependent on the first LUN */
2852 cfg->product_name ?: (common->luns->cdrom
2853 ? "File-Stor Gadget"
2854 : "File-CD Gadget"),
2858 * Some peripheral controllers are known not to be able to
2859 * halt bulk endpoints correctly. If one of them is present,
2862 common->can_stall = cfg->can_stall &&
2863 !(gadget_is_at91(common->gadget));
2865 spin_lock_init(&common->lock);
2866 kref_init(&common->ref);
2868 /* Tell the thread to start working */
2869 common->thread_task =
2870 kthread_create(fsg_main_thread, common,
2871 cfg->thread_name ?: "file-storage");
2872 if (IS_ERR(common->thread_task)) {
2873 rc = PTR_ERR(common->thread_task);
2876 init_completion(&common->thread_notifier);
2877 init_waitqueue_head(&common->fsg_wait);
2880 INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2881 INFO(common, "Number of LUNs=%d\n", common->nluns);
2883 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2884 for (i = 0, nluns = common->nluns, curlun = common->luns;
2887 char *p = "(no medium)";
2888 if (fsg_lun_is_open(curlun)) {
2891 p = d_path(&curlun->filp->f_path,
2897 LINFO(curlun, "LUN: %s%s%sfile: %s\n",
2898 curlun->removable ? "removable " : "",
2899 curlun->ro ? "read only " : "",
2900 curlun->cdrom ? "CD-ROM " : "",
2905 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
2907 wake_up_process(common->thread_task);
2912 common->nluns = i + 1;
2914 common->state = FSG_STATE_TERMINATED; /* The thread is dead */
2915 /* Call fsg_common_release() directly, ref might be not initialised. */
2916 fsg_common_release(&common->ref);
2920 static void fsg_common_release(struct kref *ref)
2922 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
2924 /* If the thread isn't already dead, tell it to exit now */
2925 if (common->state != FSG_STATE_TERMINATED) {
2926 raise_exception(common, FSG_STATE_EXIT);
2927 wait_for_completion(&common->thread_notifier);
2930 if (likely(common->luns)) {
2931 struct fsg_lun *lun = common->luns;
2932 unsigned i = common->nluns;
2934 /* In error recovery common->nluns may be zero. */
2935 for (; i; --i, ++lun) {
2936 device_remove_file(&lun->dev, &dev_attr_nofua);
2937 device_remove_file(&lun->dev, &dev_attr_ro);
2938 device_remove_file(&lun->dev, &dev_attr_file);
2940 device_unregister(&lun->dev);
2943 kfree(common->luns);
2947 struct fsg_buffhd *bh = common->buffhds;
2948 unsigned i = fsg_num_buffers;
2951 } while (++bh, --i);
2954 kfree(common->buffhds);
2955 if (common->free_storage_on_release)
2960 /*-------------------------------------------------------------------------*/
2962 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
2964 struct fsg_dev *fsg = fsg_from_func(f);
2965 struct fsg_common *common = fsg->common;
2967 DBG(fsg, "unbind\n");
2968 if (fsg->common->fsg == fsg) {
2969 fsg->common->new_fsg = NULL;
2970 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2971 /* FIXME: make interruptible or killable somehow? */
2972 wait_event(common->fsg_wait, common->fsg != fsg);
2975 fsg_common_put(common);
2976 usb_free_descriptors(fsg->function.descriptors);
2977 usb_free_descriptors(fsg->function.hs_descriptors);
2981 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
2983 struct fsg_dev *fsg = fsg_from_func(f);
2984 struct usb_gadget *gadget = c->cdev->gadget;
2988 fsg->gadget = gadget;
2991 i = usb_interface_id(c, f);
2994 fsg_intf_desc.bInterfaceNumber = i;
2995 fsg->interface_number = i;
2997 /* Find all the endpoints we will use */
2998 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
3001 ep->driver_data = fsg->common; /* claim the endpoint */
3004 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
3007 ep->driver_data = fsg->common; /* claim the endpoint */
3010 /* Copy descriptors */
3011 f->descriptors = usb_copy_descriptors(fsg_fs_function);
3012 if (unlikely(!f->descriptors))
3015 if (gadget_is_dualspeed(gadget)) {
3016 /* Assume endpoint addresses are the same for both speeds */
3017 fsg_hs_bulk_in_desc.bEndpointAddress =
3018 fsg_fs_bulk_in_desc.bEndpointAddress;
3019 fsg_hs_bulk_out_desc.bEndpointAddress =
3020 fsg_fs_bulk_out_desc.bEndpointAddress;
3021 f->hs_descriptors = usb_copy_descriptors(fsg_hs_function);
3022 if (unlikely(!f->hs_descriptors)) {
3023 usb_free_descriptors(f->descriptors);
3028 if (gadget_is_superspeed(gadget)) {
3031 /* Calculate bMaxBurst, we know packet size is 1024 */
3032 max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15);
3034 fsg_ss_bulk_in_desc.bEndpointAddress =
3035 fsg_fs_bulk_in_desc.bEndpointAddress;
3036 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
3038 fsg_ss_bulk_out_desc.bEndpointAddress =
3039 fsg_fs_bulk_out_desc.bEndpointAddress;
3040 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
3042 f->ss_descriptors = usb_copy_descriptors(fsg_ss_function);
3043 if (unlikely(!f->ss_descriptors)) {
3044 usb_free_descriptors(f->hs_descriptors);
3045 usb_free_descriptors(f->descriptors);
3053 ERROR(fsg, "unable to autoconfigure all endpoints\n");
3058 /****************************** ADD FUNCTION ******************************/
3060 static struct usb_gadget_strings *fsg_strings_array[] = {
3065 static int fsg_bind_config(struct usb_composite_dev *cdev,
3066 struct usb_configuration *c,
3067 struct fsg_common *common)
3069 struct fsg_dev *fsg;
3072 fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
3076 fsg->function.name = FSG_DRIVER_DESC;
3077 fsg->function.strings = fsg_strings_array;
3078 fsg->function.bind = fsg_bind;
3079 fsg->function.unbind = fsg_unbind;
3080 fsg->function.setup = fsg_setup;
3081 fsg->function.set_alt = fsg_set_alt;
3082 fsg->function.disable = fsg_disable;
3084 fsg->common = common;
3086 * Our caller holds a reference to common structure so we
3087 * don't have to be worry about it being freed until we return
3088 * from this function. So instead of incrementing counter now
3089 * and decrement in error recovery we increment it only when
3090 * call to usb_add_function() was successful.
3093 rc = usb_add_function(c, &fsg->function);
3097 fsg_common_get(fsg->common);
3101 static inline int __deprecated __maybe_unused
3102 fsg_add(struct usb_composite_dev *cdev, struct usb_configuration *c,
3103 struct fsg_common *common)
3105 return fsg_bind_config(cdev, c, common);
3109 /************************* Module parameters *************************/
3111 struct fsg_module_parameters {
3112 char *file[FSG_MAX_LUNS];
3113 int ro[FSG_MAX_LUNS];
3114 int removable[FSG_MAX_LUNS];
3115 int cdrom[FSG_MAX_LUNS];
3116 int nofua[FSG_MAX_LUNS];
3118 unsigned int file_count, ro_count, removable_count, cdrom_count;
3119 unsigned int nofua_count;
3120 unsigned int luns; /* nluns */
3121 int stall; /* can_stall */
3124 #define _FSG_MODULE_PARAM_ARRAY(prefix, params, name, type, desc) \
3125 module_param_array_named(prefix ## name, params.name, type, \
3126 &prefix ## params.name ## _count, \
3128 MODULE_PARM_DESC(prefix ## name, desc)
3130 #define _FSG_MODULE_PARAM(prefix, params, name, type, desc) \
3131 module_param_named(prefix ## name, params.name, type, \
3133 MODULE_PARM_DESC(prefix ## name, desc)
3135 #define FSG_MODULE_PARAMETERS(prefix, params) \
3136 _FSG_MODULE_PARAM_ARRAY(prefix, params, file, charp, \
3137 "names of backing files or devices"); \
3138 _FSG_MODULE_PARAM_ARRAY(prefix, params, ro, bool, \
3139 "true to force read-only"); \
3140 _FSG_MODULE_PARAM_ARRAY(prefix, params, removable, bool, \
3141 "true to simulate removable media"); \
3142 _FSG_MODULE_PARAM_ARRAY(prefix, params, cdrom, bool, \
3143 "true to simulate CD-ROM instead of disk"); \
3144 _FSG_MODULE_PARAM_ARRAY(prefix, params, nofua, bool, \
3145 "true to ignore SCSI WRITE(10,12) FUA bit"); \
3146 _FSG_MODULE_PARAM(prefix, params, luns, uint, \
3147 "number of LUNs"); \
3148 _FSG_MODULE_PARAM(prefix, params, stall, bool, \
3149 "false to prevent bulk stalls")
3152 fsg_config_from_params(struct fsg_config *cfg,
3153 const struct fsg_module_parameters *params)
3155 struct fsg_lun_config *lun;
3158 /* Configure LUNs */
3160 min(params->luns ?: (params->file_count ?: 1u),
3161 (unsigned)FSG_MAX_LUNS);
3162 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3163 lun->ro = !!params->ro[i];
3164 lun->cdrom = !!params->cdrom[i];
3165 lun->removable = /* Removable by default */
3166 params->removable_count <= i || params->removable[i];
3168 params->file_count > i && params->file[i][0]
3173 /* Let MSF use defaults */
3174 cfg->lun_name_format = 0;
3175 cfg->thread_name = 0;
3176 cfg->vendor_name = 0;
3177 cfg->product_name = 0;
3178 cfg->release = 0xffff;
3181 cfg->private_data = NULL;
3184 cfg->can_stall = params->stall;
3187 static inline struct fsg_common *
3188 fsg_common_from_params(struct fsg_common *common,
3189 struct usb_composite_dev *cdev,
3190 const struct fsg_module_parameters *params)
3191 __attribute__((unused));
3192 static inline struct fsg_common *
3193 fsg_common_from_params(struct fsg_common *common,
3194 struct usb_composite_dev *cdev,
3195 const struct fsg_module_parameters *params)
3197 struct fsg_config cfg;
3198 fsg_config_from_params(&cfg, params);
3199 return fsg_common_init(common, cdev, &cfg);