2 * f_mass_storage.c -- Mass Storage USB Composite Function
4 * Copyright (C) 2003-2008 Alan Stern
5 * Copyright (C) 2009 Samsung Electronics
6 * Author: Michal Nazarewicz <mina86@mina86.com>
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions, and the following disclaimer,
14 * without modification.
15 * 2. Redistributions in binary form must reproduce the above copyright
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20 * specific prior written permission.
22 * ALTERNATIVELY, this software may be distributed under the terms of the
23 * GNU General Public License ("GPL") as published by the Free Software
24 * Foundation, either version 2 of that License or (at your option) any
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
28 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
29 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
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35 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
36 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
37 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 * For more information about MSF and in particular its module
48 * parameters and sysfs interface read the
49 * <Documentation/usb/mass-storage.txt> file.
53 * MSF is configured by specifying a fsg_config structure. It has the
56 * nluns Number of LUNs function have (anywhere from 1
57 * to FSG_MAX_LUNS which is 8).
58 * luns An array of LUN configuration values. This
59 * should be filled for each LUN that
60 * function will include (ie. for "nluns"
61 * LUNs). Each element of the array has
62 * the following fields:
63 * ->filename The path to the backing file for the LUN.
64 * Required if LUN is not marked as
66 * ->ro Flag specifying access to the LUN shall be
67 * read-only. This is implied if CD-ROM
68 * emulation is enabled as well as when
69 * it was impossible to open "filename"
71 * ->removable Flag specifying that LUN shall be indicated as
73 * ->cdrom Flag specifying that LUN shall be reported as
75 * ->nofua Flag specifying that FUA flag in SCSI WRITE(10,12)
76 * commands for this LUN shall be ignored.
80 * release Information used as a reply to INQUIRY
81 * request. To use default set to NULL,
82 * NULL, 0xffff respectively. The first
83 * field should be 8 and the second 16
86 * can_stall Set to permit function to halt bulk endpoints.
87 * Disabled on some USB devices known not
88 * to work correctly. You should set it
91 * If "removable" is not set for a LUN then a backing file must be
92 * specified. If it is set, then NULL filename means the LUN's medium
93 * is not loaded (an empty string as "filename" in the fsg_config
94 * structure causes error). The CD-ROM emulation includes a single
95 * data track and no audio tracks; hence there need be only one
96 * backing file per LUN.
98 * This function is heavily based on "File-backed Storage Gadget" by
99 * Alan Stern which in turn is heavily based on "Gadget Zero" by David
100 * Brownell. The driver's SCSI command interface was based on the
101 * "Information technology - Small Computer System Interface - 2"
102 * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
103 * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
104 * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
105 * was based on the "Universal Serial Bus Mass Storage Class UFI
106 * Command Specification" document, Revision 1.0, December 14, 1998,
108 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
114 * The MSF is fairly straightforward. There is a main kernel
115 * thread that handles most of the work. Interrupt routines field
116 * callbacks from the controller driver: bulk- and interrupt-request
117 * completion notifications, endpoint-0 events, and disconnect events.
118 * Completion events are passed to the main thread by wakeup calls. Many
119 * ep0 requests are handled at interrupt time, but SetInterface,
120 * SetConfiguration, and device reset requests are forwarded to the
121 * thread in the form of "exceptions" using SIGUSR1 signals (since they
122 * should interrupt any ongoing file I/O operations).
124 * The thread's main routine implements the standard command/data/status
125 * parts of a SCSI interaction. It and its subroutines are full of tests
126 * for pending signals/exceptions -- all this polling is necessary since
127 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
128 * indication that the driver really wants to be running in userspace.)
129 * An important point is that so long as the thread is alive it keeps an
130 * open reference to the backing file. This will prevent unmounting
131 * the backing file's underlying filesystem and could cause problems
132 * during system shutdown, for example. To prevent such problems, the
133 * thread catches INT, TERM, and KILL signals and converts them into
136 * In normal operation the main thread is started during the gadget's
137 * fsg_bind() callback and stopped during fsg_unbind(). But it can
138 * also exit when it receives a signal, and there's no point leaving
139 * the gadget running when the thread is dead. As of this moment, MSF
140 * provides no way to deregister the gadget when thread dies -- maybe
141 * a callback functions is needed.
143 * To provide maximum throughput, the driver uses a circular pipeline of
144 * buffer heads (struct fsg_buffhd). In principle the pipeline can be
145 * arbitrarily long; in practice the benefits don't justify having more
146 * than 2 stages (i.e., double buffering). But it helps to think of the
147 * pipeline as being a long one. Each buffer head contains a bulk-in and
148 * a bulk-out request pointer (since the buffer can be used for both
149 * output and input -- directions always are given from the host's
150 * point of view) as well as a pointer to the buffer and various state
153 * Use of the pipeline follows a simple protocol. There is a variable
154 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
155 * At any time that buffer head may still be in use from an earlier
156 * request, so each buffer head has a state variable indicating whether
157 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
158 * buffer head to be EMPTY, filling the buffer either by file I/O or by
159 * USB I/O (during which the buffer head is BUSY), and marking the buffer
160 * head FULL when the I/O is complete. Then the buffer will be emptied
161 * (again possibly by USB I/O, during which it is marked BUSY) and
162 * finally marked EMPTY again (possibly by a completion routine).
164 * A module parameter tells the driver to avoid stalling the bulk
165 * endpoints wherever the transport specification allows. This is
166 * necessary for some UDCs like the SuperH, which cannot reliably clear a
167 * halt on a bulk endpoint. However, under certain circumstances the
168 * Bulk-only specification requires a stall. In such cases the driver
169 * will halt the endpoint and set a flag indicating that it should clear
170 * the halt in software during the next device reset. Hopefully this
171 * will permit everything to work correctly. Furthermore, although the
172 * specification allows the bulk-out endpoint to halt when the host sends
173 * too much data, implementing this would cause an unavoidable race.
174 * The driver will always use the "no-stall" approach for OUT transfers.
176 * One subtle point concerns sending status-stage responses for ep0
177 * requests. Some of these requests, such as device reset, can involve
178 * interrupting an ongoing file I/O operation, which might take an
179 * arbitrarily long time. During that delay the host might give up on
180 * the original ep0 request and issue a new one. When that happens the
181 * driver should not notify the host about completion of the original
182 * request, as the host will no longer be waiting for it. So the driver
183 * assigns to each ep0 request a unique tag, and it keeps track of the
184 * tag value of the request associated with a long-running exception
185 * (device-reset, interface-change, or configuration-change). When the
186 * exception handler is finished, the status-stage response is submitted
187 * only if the current ep0 request tag is equal to the exception request
188 * tag. Thus only the most recently received ep0 request will get a
189 * status-stage response.
191 * Warning: This driver source file is too long. It ought to be split up
192 * into a header file plus about 3 separate .c files, to handle the details
193 * of the Gadget, USB Mass Storage, and SCSI protocols.
197 /* #define VERBOSE_DEBUG */
198 /* #define DUMP_MSGS */
200 #include <linux/blkdev.h>
201 #include <linux/completion.h>
202 #include <linux/dcache.h>
203 #include <linux/delay.h>
204 #include <linux/device.h>
205 #include <linux/fcntl.h>
206 #include <linux/file.h>
207 #include <linux/fs.h>
208 #include <linux/kref.h>
209 #include <linux/kthread.h>
210 #include <linux/limits.h>
211 #include <linux/rwsem.h>
212 #include <linux/slab.h>
213 #include <linux/spinlock.h>
214 #include <linux/string.h>
215 #include <linux/freezer.h>
217 #include <linux/usb/ch9.h>
218 #include <linux/usb/gadget.h>
219 #include <linux/usb/composite.h>
221 #include "gadget_chips.h"
224 /*------------------------------------------------------------------------*/
226 #define FSG_DRIVER_DESC "Mass Storage Function"
227 #define FSG_DRIVER_VERSION "2009/09/11"
229 static const char fsg_string_interface[] = "Mass Storage";
231 #include "storage_common.c"
234 /*-------------------------------------------------------------------------*/
239 /* FSF callback functions */
240 struct fsg_operations {
242 * Callback function to call when thread exits. If no
243 * callback is set or it returns value lower then zero MSF
244 * will force eject all LUNs it operates on (including those
245 * marked as non-removable or with prevent_medium_removal flag
248 int (*thread_exits)(struct fsg_common *common);
251 /* Data shared by all the FSG instances. */
253 struct usb_gadget *gadget;
254 struct usb_composite_dev *cdev;
255 struct fsg_dev *fsg, *new_fsg;
256 wait_queue_head_t fsg_wait;
258 /* filesem protects: backing files in use */
259 struct rw_semaphore filesem;
261 /* lock protects: state, all the req_busy's */
264 struct usb_ep *ep0; /* Copy of gadget->ep0 */
265 struct usb_request *ep0req; /* Copy of cdev->req */
266 unsigned int ep0_req_tag;
268 struct fsg_buffhd *next_buffhd_to_fill;
269 struct fsg_buffhd *next_buffhd_to_drain;
270 struct fsg_buffhd *buffhds;
273 u8 cmnd[MAX_COMMAND_SIZE];
277 struct fsg_lun *luns;
278 struct fsg_lun *curlun;
280 unsigned int bulk_out_maxpacket;
281 enum fsg_state state; /* For exception handling */
282 unsigned int exception_req_tag;
284 enum data_direction data_dir;
286 u32 data_size_from_cmnd;
291 unsigned int can_stall:1;
292 unsigned int free_storage_on_release:1;
293 unsigned int phase_error:1;
294 unsigned int short_packet_received:1;
295 unsigned int bad_lun_okay:1;
296 unsigned int running:1;
298 int thread_wakeup_needed;
299 struct completion thread_notifier;
300 struct task_struct *thread_task;
302 /* Callback functions. */
303 const struct fsg_operations *ops;
304 /* Gadget's private data. */
308 * Vendor (8 chars), product (16 chars), release (4
309 * hexadecimal digits) and NUL byte
311 char inquiry_string[8 + 16 + 4 + 1];
318 struct fsg_lun_config {
319 const char *filename;
324 } luns[FSG_MAX_LUNS];
326 /* Callback functions. */
327 const struct fsg_operations *ops;
328 /* Gadget's private data. */
331 const char *vendor_name; /* 8 characters or less */
332 const char *product_name; /* 16 characters or less */
338 struct usb_function function;
339 struct usb_gadget *gadget; /* Copy of cdev->gadget */
340 struct fsg_common *common;
342 u16 interface_number;
344 unsigned int bulk_in_enabled:1;
345 unsigned int bulk_out_enabled:1;
347 unsigned long atomic_bitflags;
348 #define IGNORE_BULK_OUT 0
350 struct usb_ep *bulk_in;
351 struct usb_ep *bulk_out;
354 static inline int __fsg_is_set(struct fsg_common *common,
355 const char *func, unsigned line)
359 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
364 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
366 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
368 return container_of(f, struct fsg_dev, function);
371 typedef void (*fsg_routine_t)(struct fsg_dev *);
373 static int exception_in_progress(struct fsg_common *common)
375 return common->state > FSG_STATE_IDLE;
378 /* Make bulk-out requests be divisible by the maxpacket size */
379 static void set_bulk_out_req_length(struct fsg_common *common,
380 struct fsg_buffhd *bh, unsigned int length)
384 bh->bulk_out_intended_length = length;
385 rem = length % common->bulk_out_maxpacket;
387 length += common->bulk_out_maxpacket - rem;
388 bh->outreq->length = length;
392 /*-------------------------------------------------------------------------*/
394 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
398 if (ep == fsg->bulk_in)
400 else if (ep == fsg->bulk_out)
404 DBG(fsg, "%s set halt\n", name);
405 return usb_ep_set_halt(ep);
409 /*-------------------------------------------------------------------------*/
411 /* These routines may be called in process context or in_irq */
413 /* Caller must hold fsg->lock */
414 static void wakeup_thread(struct fsg_common *common)
416 /* Tell the main thread that something has happened */
417 common->thread_wakeup_needed = 1;
418 if (common->thread_task)
419 wake_up_process(common->thread_task);
422 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
427 * Do nothing if a higher-priority exception is already in progress.
428 * If a lower-or-equal priority exception is in progress, preempt it
429 * and notify the main thread by sending it a signal.
431 spin_lock_irqsave(&common->lock, flags);
432 if (common->state <= new_state) {
433 common->exception_req_tag = common->ep0_req_tag;
434 common->state = new_state;
435 if (common->thread_task)
436 send_sig_info(SIGUSR1, SEND_SIG_FORCED,
437 common->thread_task);
439 spin_unlock_irqrestore(&common->lock, flags);
443 /*-------------------------------------------------------------------------*/
445 static int ep0_queue(struct fsg_common *common)
449 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
450 common->ep0->driver_data = common;
451 if (rc != 0 && rc != -ESHUTDOWN) {
452 /* We can't do much more than wait for a reset */
453 WARNING(common, "error in submission: %s --> %d\n",
454 common->ep0->name, rc);
460 /*-------------------------------------------------------------------------*/
462 /* Completion handlers. These always run in_irq. */
464 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
466 struct fsg_common *common = ep->driver_data;
467 struct fsg_buffhd *bh = req->context;
469 if (req->status || req->actual != req->length)
470 DBG(common, "%s --> %d, %u/%u\n", __func__,
471 req->status, req->actual, req->length);
472 if (req->status == -ECONNRESET) /* Request was cancelled */
473 usb_ep_fifo_flush(ep);
475 /* Hold the lock while we update the request and buffer states */
477 spin_lock(&common->lock);
479 bh->state = BUF_STATE_EMPTY;
480 wakeup_thread(common);
481 spin_unlock(&common->lock);
484 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
486 struct fsg_common *common = ep->driver_data;
487 struct fsg_buffhd *bh = req->context;
489 dump_msg(common, "bulk-out", req->buf, req->actual);
490 if (req->status || req->actual != bh->bulk_out_intended_length)
491 DBG(common, "%s --> %d, %u/%u\n", __func__,
492 req->status, req->actual, bh->bulk_out_intended_length);
493 if (req->status == -ECONNRESET) /* Request was cancelled */
494 usb_ep_fifo_flush(ep);
496 /* Hold the lock while we update the request and buffer states */
498 spin_lock(&common->lock);
500 bh->state = BUF_STATE_FULL;
501 wakeup_thread(common);
502 spin_unlock(&common->lock);
505 static int fsg_setup(struct usb_function *f,
506 const struct usb_ctrlrequest *ctrl)
508 struct fsg_dev *fsg = fsg_from_func(f);
509 struct usb_request *req = fsg->common->ep0req;
510 u16 w_index = le16_to_cpu(ctrl->wIndex);
511 u16 w_value = le16_to_cpu(ctrl->wValue);
512 u16 w_length = le16_to_cpu(ctrl->wLength);
514 if (!fsg_is_set(fsg->common))
517 ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
520 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
522 switch (ctrl->bRequest) {
524 case US_BULK_RESET_REQUEST:
525 if (ctrl->bRequestType !=
526 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
528 if (w_index != fsg->interface_number || w_value != 0 ||
533 * Raise an exception to stop the current operation
534 * and reinitialize our state.
536 DBG(fsg, "bulk reset request\n");
537 raise_exception(fsg->common, FSG_STATE_RESET);
538 return DELAYED_STATUS;
540 case US_BULK_GET_MAX_LUN:
541 if (ctrl->bRequestType !=
542 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
544 if (w_index != fsg->interface_number || w_value != 0 ||
547 VDBG(fsg, "get max LUN\n");
548 *(u8 *)req->buf = fsg->common->nluns - 1;
550 /* Respond with data/status */
551 req->length = min((u16)1, w_length);
552 return ep0_queue(fsg->common);
556 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
557 ctrl->bRequestType, ctrl->bRequest,
558 le16_to_cpu(ctrl->wValue), w_index, w_length);
563 /*-------------------------------------------------------------------------*/
565 /* All the following routines run in process context */
567 /* Use this for bulk or interrupt transfers, not ep0 */
568 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
569 struct usb_request *req, int *pbusy,
570 enum fsg_buffer_state *state)
574 if (ep == fsg->bulk_in)
575 dump_msg(fsg, "bulk-in", req->buf, req->length);
577 spin_lock_irq(&fsg->common->lock);
579 *state = BUF_STATE_BUSY;
580 spin_unlock_irq(&fsg->common->lock);
581 rc = usb_ep_queue(ep, req, GFP_KERNEL);
584 *state = BUF_STATE_EMPTY;
586 /* We can't do much more than wait for a reset */
589 * Note: currently the net2280 driver fails zero-length
590 * submissions if DMA is enabled.
592 if (rc != -ESHUTDOWN &&
593 !(rc == -EOPNOTSUPP && req->length == 0))
594 WARNING(fsg, "error in submission: %s --> %d\n",
599 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
601 if (!fsg_is_set(common))
603 start_transfer(common->fsg, common->fsg->bulk_in,
604 bh->inreq, &bh->inreq_busy, &bh->state);
608 static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
610 if (!fsg_is_set(common))
612 start_transfer(common->fsg, common->fsg->bulk_out,
613 bh->outreq, &bh->outreq_busy, &bh->state);
617 static int sleep_thread(struct fsg_common *common)
621 /* Wait until a signal arrives or we are woken up */
624 set_current_state(TASK_INTERRUPTIBLE);
625 if (signal_pending(current)) {
629 if (common->thread_wakeup_needed)
633 __set_current_state(TASK_RUNNING);
634 common->thread_wakeup_needed = 0;
639 /*-------------------------------------------------------------------------*/
641 static int do_read(struct fsg_common *common)
643 struct fsg_lun *curlun = common->curlun;
645 struct fsg_buffhd *bh;
648 loff_t file_offset, file_offset_tmp;
653 * Get the starting Logical Block Address and check that it's
656 if (common->cmnd[0] == READ_6)
657 lba = get_unaligned_be24(&common->cmnd[1]);
659 lba = get_unaligned_be32(&common->cmnd[2]);
662 * We allow DPO (Disable Page Out = don't save data in the
663 * cache) and FUA (Force Unit Access = don't read from the
664 * cache), but we don't implement them.
666 if ((common->cmnd[1] & ~0x18) != 0) {
667 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
671 if (lba >= curlun->num_sectors) {
672 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
675 file_offset = ((loff_t) lba) << curlun->blkbits;
677 /* Carry out the file reads */
678 amount_left = common->data_size_from_cmnd;
679 if (unlikely(amount_left == 0))
680 return -EIO; /* No default reply */
684 * Figure out how much we need to read:
685 * Try to read the remaining amount.
686 * But don't read more than the buffer size.
687 * And don't try to read past the end of the file.
689 amount = min(amount_left, FSG_BUFLEN);
690 amount = min((loff_t)amount,
691 curlun->file_length - file_offset);
693 /* Wait for the next buffer to become available */
694 bh = common->next_buffhd_to_fill;
695 while (bh->state != BUF_STATE_EMPTY) {
696 rc = sleep_thread(common);
702 * If we were asked to read past the end of file,
703 * end with an empty buffer.
707 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
708 curlun->sense_data_info =
709 file_offset >> curlun->blkbits;
710 curlun->info_valid = 1;
711 bh->inreq->length = 0;
712 bh->state = BUF_STATE_FULL;
716 /* Perform the read */
717 file_offset_tmp = file_offset;
718 nread = vfs_read(curlun->filp,
719 (char __user *)bh->buf,
720 amount, &file_offset_tmp);
721 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
722 (unsigned long long)file_offset, (int)nread);
723 if (signal_pending(current))
727 LDBG(curlun, "error in file read: %d\n", (int)nread);
729 } else if (nread < amount) {
730 LDBG(curlun, "partial file read: %d/%u\n",
732 nread = round_down(nread, curlun->blksize);
734 file_offset += nread;
735 amount_left -= nread;
736 common->residue -= nread;
739 * Except at the end of the transfer, nread will be
740 * equal to the buffer size, which is divisible by the
741 * bulk-in maxpacket size.
743 bh->inreq->length = nread;
744 bh->state = BUF_STATE_FULL;
746 /* If an error occurred, report it and its position */
747 if (nread < amount) {
748 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
749 curlun->sense_data_info =
750 file_offset >> curlun->blkbits;
751 curlun->info_valid = 1;
755 if (amount_left == 0)
756 break; /* No more left to read */
758 /* Send this buffer and go read some more */
760 if (!start_in_transfer(common, bh))
761 /* Don't know what to do if common->fsg is NULL */
763 common->next_buffhd_to_fill = bh->next;
766 return -EIO; /* No default reply */
770 /*-------------------------------------------------------------------------*/
772 static int do_write(struct fsg_common *common)
774 struct fsg_lun *curlun = common->curlun;
776 struct fsg_buffhd *bh;
778 u32 amount_left_to_req, amount_left_to_write;
779 loff_t usb_offset, file_offset, file_offset_tmp;
785 curlun->sense_data = SS_WRITE_PROTECTED;
788 spin_lock(&curlun->filp->f_lock);
789 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
790 spin_unlock(&curlun->filp->f_lock);
793 * Get the starting Logical Block Address and check that it's
796 if (common->cmnd[0] == WRITE_6)
797 lba = get_unaligned_be24(&common->cmnd[1]);
799 lba = get_unaligned_be32(&common->cmnd[2]);
802 * We allow DPO (Disable Page Out = don't save data in the
803 * cache) and FUA (Force Unit Access = write directly to the
804 * medium). We don't implement DPO; we implement FUA by
805 * performing synchronous output.
807 if (common->cmnd[1] & ~0x18) {
808 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
811 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
812 spin_lock(&curlun->filp->f_lock);
813 curlun->filp->f_flags |= O_SYNC;
814 spin_unlock(&curlun->filp->f_lock);
817 if (lba >= curlun->num_sectors) {
818 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
822 /* Carry out the file writes */
824 file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
825 amount_left_to_req = common->data_size_from_cmnd;
826 amount_left_to_write = common->data_size_from_cmnd;
828 while (amount_left_to_write > 0) {
830 /* Queue a request for more data from the host */
831 bh = common->next_buffhd_to_fill;
832 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
835 * Figure out how much we want to get:
836 * Try to get the remaining amount,
837 * but not more than the buffer size.
839 amount = min(amount_left_to_req, FSG_BUFLEN);
841 /* Beyond the end of the backing file? */
842 if (usb_offset >= curlun->file_length) {
845 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
846 curlun->sense_data_info =
847 usb_offset >> curlun->blkbits;
848 curlun->info_valid = 1;
852 /* Get the next buffer */
853 usb_offset += amount;
854 common->usb_amount_left -= amount;
855 amount_left_to_req -= amount;
856 if (amount_left_to_req == 0)
860 * Except at the end of the transfer, amount will be
861 * equal to the buffer size, which is divisible by
862 * the bulk-out maxpacket size.
864 set_bulk_out_req_length(common, bh, amount);
865 if (!start_out_transfer(common, bh))
866 /* Dunno what to do if common->fsg is NULL */
868 common->next_buffhd_to_fill = bh->next;
872 /* Write the received data to the backing file */
873 bh = common->next_buffhd_to_drain;
874 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
875 break; /* We stopped early */
876 if (bh->state == BUF_STATE_FULL) {
878 common->next_buffhd_to_drain = bh->next;
879 bh->state = BUF_STATE_EMPTY;
881 /* Did something go wrong with the transfer? */
882 if (bh->outreq->status != 0) {
883 curlun->sense_data = SS_COMMUNICATION_FAILURE;
884 curlun->sense_data_info =
885 file_offset >> curlun->blkbits;
886 curlun->info_valid = 1;
890 amount = bh->outreq->actual;
891 if (curlun->file_length - file_offset < amount) {
893 "write %u @ %llu beyond end %llu\n",
894 amount, (unsigned long long)file_offset,
895 (unsigned long long)curlun->file_length);
896 amount = curlun->file_length - file_offset;
899 /* Don't accept excess data. The spec doesn't say
900 * what to do in this case. We'll ignore the error.
902 amount = min(amount, bh->bulk_out_intended_length);
904 /* Don't write a partial block */
905 amount = round_down(amount, curlun->blksize);
909 /* Perform the write */
910 file_offset_tmp = file_offset;
911 nwritten = vfs_write(curlun->filp,
912 (char __user *)bh->buf,
913 amount, &file_offset_tmp);
914 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
915 (unsigned long long)file_offset, (int)nwritten);
916 if (signal_pending(current))
917 return -EINTR; /* Interrupted! */
920 LDBG(curlun, "error in file write: %d\n",
923 } else if (nwritten < amount) {
924 LDBG(curlun, "partial file write: %d/%u\n",
925 (int)nwritten, amount);
926 nwritten = round_down(nwritten, curlun->blksize);
928 file_offset += nwritten;
929 amount_left_to_write -= nwritten;
930 common->residue -= nwritten;
932 /* If an error occurred, report it and its position */
933 if (nwritten < amount) {
934 curlun->sense_data = SS_WRITE_ERROR;
935 curlun->sense_data_info =
936 file_offset >> curlun->blkbits;
937 curlun->info_valid = 1;
942 /* Did the host decide to stop early? */
943 if (bh->outreq->actual < bh->bulk_out_intended_length) {
944 common->short_packet_received = 1;
950 /* Wait for something to happen */
951 rc = sleep_thread(common);
956 return -EIO; /* No default reply */
960 /*-------------------------------------------------------------------------*/
962 static int do_synchronize_cache(struct fsg_common *common)
964 struct fsg_lun *curlun = common->curlun;
967 /* We ignore the requested LBA and write out all file's
968 * dirty data buffers. */
969 rc = fsg_lun_fsync_sub(curlun);
971 curlun->sense_data = SS_WRITE_ERROR;
976 /*-------------------------------------------------------------------------*/
978 static void invalidate_sub(struct fsg_lun *curlun)
980 struct file *filp = curlun->filp;
981 struct inode *inode = file_inode(filp);
984 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
985 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
988 static int do_verify(struct fsg_common *common)
990 struct fsg_lun *curlun = common->curlun;
992 u32 verification_length;
993 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
994 loff_t file_offset, file_offset_tmp;
1000 * Get the starting Logical Block Address and check that it's
1003 lba = get_unaligned_be32(&common->cmnd[2]);
1004 if (lba >= curlun->num_sectors) {
1005 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1010 * We allow DPO (Disable Page Out = don't save data in the
1011 * cache) but we don't implement it.
1013 if (common->cmnd[1] & ~0x10) {
1014 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1018 verification_length = get_unaligned_be16(&common->cmnd[7]);
1019 if (unlikely(verification_length == 0))
1020 return -EIO; /* No default reply */
1022 /* Prepare to carry out the file verify */
1023 amount_left = verification_length << curlun->blkbits;
1024 file_offset = ((loff_t) lba) << curlun->blkbits;
1026 /* Write out all the dirty buffers before invalidating them */
1027 fsg_lun_fsync_sub(curlun);
1028 if (signal_pending(current))
1031 invalidate_sub(curlun);
1032 if (signal_pending(current))
1035 /* Just try to read the requested blocks */
1036 while (amount_left > 0) {
1038 * Figure out how much we need to read:
1039 * Try to read the remaining amount, but not more than
1041 * And don't try to read past the end of the file.
1043 amount = min(amount_left, FSG_BUFLEN);
1044 amount = min((loff_t)amount,
1045 curlun->file_length - file_offset);
1047 curlun->sense_data =
1048 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1049 curlun->sense_data_info =
1050 file_offset >> curlun->blkbits;
1051 curlun->info_valid = 1;
1055 /* Perform the read */
1056 file_offset_tmp = file_offset;
1057 nread = vfs_read(curlun->filp,
1058 (char __user *) bh->buf,
1059 amount, &file_offset_tmp);
1060 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1061 (unsigned long long) file_offset,
1063 if (signal_pending(current))
1067 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1069 } else if (nread < amount) {
1070 LDBG(curlun, "partial file verify: %d/%u\n",
1071 (int)nread, amount);
1072 nread = round_down(nread, curlun->blksize);
1075 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1076 curlun->sense_data_info =
1077 file_offset >> curlun->blkbits;
1078 curlun->info_valid = 1;
1081 file_offset += nread;
1082 amount_left -= nread;
1088 /*-------------------------------------------------------------------------*/
1090 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1092 struct fsg_lun *curlun = common->curlun;
1093 u8 *buf = (u8 *) bh->buf;
1095 if (!curlun) { /* Unsupported LUNs are okay */
1096 common->bad_lun_okay = 1;
1098 buf[0] = 0x7f; /* Unsupported, no device-type */
1099 buf[4] = 31; /* Additional length */
1103 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1104 buf[1] = curlun->removable ? 0x80 : 0;
1105 buf[2] = 2; /* ANSI SCSI level 2 */
1106 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1107 buf[4] = 31; /* Additional length */
1108 buf[5] = 0; /* No special options */
1111 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1115 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1117 struct fsg_lun *curlun = common->curlun;
1118 u8 *buf = (u8 *) bh->buf;
1123 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1125 * If a REQUEST SENSE command is received from an initiator
1126 * with a pending unit attention condition (before the target
1127 * generates the contingent allegiance condition), then the
1128 * target shall either:
1129 * a) report any pending sense data and preserve the unit
1130 * attention condition on the logical unit, or,
1131 * b) report the unit attention condition, may discard any
1132 * pending sense data, and clear the unit attention
1133 * condition on the logical unit for that initiator.
1135 * FSG normally uses option a); enable this code to use option b).
1138 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1139 curlun->sense_data = curlun->unit_attention_data;
1140 curlun->unit_attention_data = SS_NO_SENSE;
1144 if (!curlun) { /* Unsupported LUNs are okay */
1145 common->bad_lun_okay = 1;
1146 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1150 sd = curlun->sense_data;
1151 sdinfo = curlun->sense_data_info;
1152 valid = curlun->info_valid << 7;
1153 curlun->sense_data = SS_NO_SENSE;
1154 curlun->sense_data_info = 0;
1155 curlun->info_valid = 0;
1159 buf[0] = valid | 0x70; /* Valid, current error */
1161 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1162 buf[7] = 18 - 8; /* Additional sense length */
1168 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1170 struct fsg_lun *curlun = common->curlun;
1171 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1172 int pmi = common->cmnd[8];
1173 u8 *buf = (u8 *)bh->buf;
1175 /* Check the PMI and LBA fields */
1176 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1177 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1181 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1182 /* Max logical block */
1183 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1187 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1189 struct fsg_lun *curlun = common->curlun;
1190 int msf = common->cmnd[1] & 0x02;
1191 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1192 u8 *buf = (u8 *)bh->buf;
1194 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1195 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1198 if (lba >= curlun->num_sectors) {
1199 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1204 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1205 store_cdrom_address(&buf[4], msf, lba);
1209 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1211 struct fsg_lun *curlun = common->curlun;
1212 int msf = common->cmnd[1] & 0x02;
1213 int start_track = common->cmnd[6];
1214 u8 *buf = (u8 *)bh->buf;
1216 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1218 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1223 buf[1] = (20-2); /* TOC data length */
1224 buf[2] = 1; /* First track number */
1225 buf[3] = 1; /* Last track number */
1226 buf[5] = 0x16; /* Data track, copying allowed */
1227 buf[6] = 0x01; /* Only track is number 1 */
1228 store_cdrom_address(&buf[8], msf, 0);
1230 buf[13] = 0x16; /* Lead-out track is data */
1231 buf[14] = 0xAA; /* Lead-out track number */
1232 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1236 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1238 struct fsg_lun *curlun = common->curlun;
1239 int mscmnd = common->cmnd[0];
1240 u8 *buf = (u8 *) bh->buf;
1243 int changeable_values, all_pages;
1247 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1248 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1251 pc = common->cmnd[2] >> 6;
1252 page_code = common->cmnd[2] & 0x3f;
1254 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1257 changeable_values = (pc == 1);
1258 all_pages = (page_code == 0x3f);
1261 * Write the mode parameter header. Fixed values are: default
1262 * medium type, no cache control (DPOFUA), and no block descriptors.
1263 * The only variable value is the WriteProtect bit. We will fill in
1264 * the mode data length later.
1267 if (mscmnd == MODE_SENSE) {
1268 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1271 } else { /* MODE_SENSE_10 */
1272 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1274 limit = 65535; /* Should really be FSG_BUFLEN */
1277 /* No block descriptors */
1280 * The mode pages, in numerical order. The only page we support
1281 * is the Caching page.
1283 if (page_code == 0x08 || all_pages) {
1285 buf[0] = 0x08; /* Page code */
1286 buf[1] = 10; /* Page length */
1287 memset(buf+2, 0, 10); /* None of the fields are changeable */
1289 if (!changeable_values) {
1290 buf[2] = 0x04; /* Write cache enable, */
1291 /* Read cache not disabled */
1292 /* No cache retention priorities */
1293 put_unaligned_be16(0xffff, &buf[4]);
1294 /* Don't disable prefetch */
1295 /* Minimum prefetch = 0 */
1296 put_unaligned_be16(0xffff, &buf[8]);
1297 /* Maximum prefetch */
1298 put_unaligned_be16(0xffff, &buf[10]);
1299 /* Maximum prefetch ceiling */
1305 * Check that a valid page was requested and the mode data length
1309 if (!valid_page || len > limit) {
1310 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1314 /* Store the mode data length */
1315 if (mscmnd == MODE_SENSE)
1318 put_unaligned_be16(len - 2, buf0);
1322 static int do_start_stop(struct fsg_common *common)
1324 struct fsg_lun *curlun = common->curlun;
1329 } else if (!curlun->removable) {
1330 curlun->sense_data = SS_INVALID_COMMAND;
1332 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1333 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1334 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1338 loej = common->cmnd[4] & 0x02;
1339 start = common->cmnd[4] & 0x01;
1342 * Our emulation doesn't support mounting; the medium is
1343 * available for use as soon as it is loaded.
1346 if (!fsg_lun_is_open(curlun)) {
1347 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1353 /* Are we allowed to unload the media? */
1354 if (curlun->prevent_medium_removal) {
1355 LDBG(curlun, "unload attempt prevented\n");
1356 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1363 up_read(&common->filesem);
1364 down_write(&common->filesem);
1365 fsg_lun_close(curlun);
1366 up_write(&common->filesem);
1367 down_read(&common->filesem);
1372 static int do_prevent_allow(struct fsg_common *common)
1374 struct fsg_lun *curlun = common->curlun;
1377 if (!common->curlun) {
1379 } else if (!common->curlun->removable) {
1380 common->curlun->sense_data = SS_INVALID_COMMAND;
1384 prevent = common->cmnd[4] & 0x01;
1385 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1386 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1390 if (curlun->prevent_medium_removal && !prevent)
1391 fsg_lun_fsync_sub(curlun);
1392 curlun->prevent_medium_removal = prevent;
1396 static int do_read_format_capacities(struct fsg_common *common,
1397 struct fsg_buffhd *bh)
1399 struct fsg_lun *curlun = common->curlun;
1400 u8 *buf = (u8 *) bh->buf;
1402 buf[0] = buf[1] = buf[2] = 0;
1403 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1406 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1407 /* Number of blocks */
1408 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1409 buf[4] = 0x02; /* Current capacity */
1413 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1415 struct fsg_lun *curlun = common->curlun;
1417 /* We don't support MODE SELECT */
1419 curlun->sense_data = SS_INVALID_COMMAND;
1424 /*-------------------------------------------------------------------------*/
1426 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1430 rc = fsg_set_halt(fsg, fsg->bulk_in);
1432 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1434 if (rc != -EAGAIN) {
1435 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1440 /* Wait for a short time and then try again */
1441 if (msleep_interruptible(100) != 0)
1443 rc = usb_ep_set_halt(fsg->bulk_in);
1448 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1452 DBG(fsg, "bulk-in set wedge\n");
1453 rc = usb_ep_set_wedge(fsg->bulk_in);
1455 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1457 if (rc != -EAGAIN) {
1458 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1463 /* Wait for a short time and then try again */
1464 if (msleep_interruptible(100) != 0)
1466 rc = usb_ep_set_wedge(fsg->bulk_in);
1471 static int throw_away_data(struct fsg_common *common)
1473 struct fsg_buffhd *bh;
1477 for (bh = common->next_buffhd_to_drain;
1478 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1479 bh = common->next_buffhd_to_drain) {
1481 /* Throw away the data in a filled buffer */
1482 if (bh->state == BUF_STATE_FULL) {
1484 bh->state = BUF_STATE_EMPTY;
1485 common->next_buffhd_to_drain = bh->next;
1487 /* A short packet or an error ends everything */
1488 if (bh->outreq->actual < bh->bulk_out_intended_length ||
1489 bh->outreq->status != 0) {
1490 raise_exception(common,
1491 FSG_STATE_ABORT_BULK_OUT);
1497 /* Try to submit another request if we need one */
1498 bh = common->next_buffhd_to_fill;
1499 if (bh->state == BUF_STATE_EMPTY
1500 && common->usb_amount_left > 0) {
1501 amount = min(common->usb_amount_left, FSG_BUFLEN);
1504 * Except at the end of the transfer, amount will be
1505 * equal to the buffer size, which is divisible by
1506 * the bulk-out maxpacket size.
1508 set_bulk_out_req_length(common, bh, amount);
1509 if (!start_out_transfer(common, bh))
1510 /* Dunno what to do if common->fsg is NULL */
1512 common->next_buffhd_to_fill = bh->next;
1513 common->usb_amount_left -= amount;
1517 /* Otherwise wait for something to happen */
1518 rc = sleep_thread(common);
1525 static int finish_reply(struct fsg_common *common)
1527 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1530 switch (common->data_dir) {
1532 break; /* Nothing to send */
1535 * If we don't know whether the host wants to read or write,
1536 * this must be CB or CBI with an unknown command. We mustn't
1537 * try to send or receive any data. So stall both bulk pipes
1538 * if we can and wait for a reset.
1540 case DATA_DIR_UNKNOWN:
1541 if (!common->can_stall) {
1543 } else if (fsg_is_set(common)) {
1544 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1545 rc = halt_bulk_in_endpoint(common->fsg);
1547 /* Don't know what to do if common->fsg is NULL */
1552 /* All but the last buffer of data must have already been sent */
1553 case DATA_DIR_TO_HOST:
1554 if (common->data_size == 0) {
1555 /* Nothing to send */
1557 /* Don't know what to do if common->fsg is NULL */
1558 } else if (!fsg_is_set(common)) {
1561 /* If there's no residue, simply send the last buffer */
1562 } else if (common->residue == 0) {
1563 bh->inreq->zero = 0;
1564 if (!start_in_transfer(common, bh))
1566 common->next_buffhd_to_fill = bh->next;
1569 * For Bulk-only, mark the end of the data with a short
1570 * packet. If we are allowed to stall, halt the bulk-in
1571 * endpoint. (Note: This violates the Bulk-Only Transport
1572 * specification, which requires us to pad the data if we
1573 * don't halt the endpoint. Presumably nobody will mind.)
1576 bh->inreq->zero = 1;
1577 if (!start_in_transfer(common, bh))
1579 common->next_buffhd_to_fill = bh->next;
1580 if (common->can_stall)
1581 rc = halt_bulk_in_endpoint(common->fsg);
1586 * We have processed all we want from the data the host has sent.
1587 * There may still be outstanding bulk-out requests.
1589 case DATA_DIR_FROM_HOST:
1590 if (common->residue == 0) {
1591 /* Nothing to receive */
1593 /* Did the host stop sending unexpectedly early? */
1594 } else if (common->short_packet_received) {
1595 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1599 * We haven't processed all the incoming data. Even though
1600 * we may be allowed to stall, doing so would cause a race.
1601 * The controller may already have ACK'ed all the remaining
1602 * bulk-out packets, in which case the host wouldn't see a
1603 * STALL. Not realizing the endpoint was halted, it wouldn't
1604 * clear the halt -- leading to problems later on.
1607 } else if (common->can_stall) {
1608 if (fsg_is_set(common))
1609 fsg_set_halt(common->fsg,
1610 common->fsg->bulk_out);
1611 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1616 * We can't stall. Read in the excess data and throw it
1620 rc = throw_away_data(common);
1627 static int send_status(struct fsg_common *common)
1629 struct fsg_lun *curlun = common->curlun;
1630 struct fsg_buffhd *bh;
1631 struct bulk_cs_wrap *csw;
1633 u8 status = US_BULK_STAT_OK;
1636 /* Wait for the next buffer to become available */
1637 bh = common->next_buffhd_to_fill;
1638 while (bh->state != BUF_STATE_EMPTY) {
1639 rc = sleep_thread(common);
1645 sd = curlun->sense_data;
1646 sdinfo = curlun->sense_data_info;
1647 } else if (common->bad_lun_okay)
1650 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1652 if (common->phase_error) {
1653 DBG(common, "sending phase-error status\n");
1654 status = US_BULK_STAT_PHASE;
1655 sd = SS_INVALID_COMMAND;
1656 } else if (sd != SS_NO_SENSE) {
1657 DBG(common, "sending command-failure status\n");
1658 status = US_BULK_STAT_FAIL;
1659 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1661 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1664 /* Store and send the Bulk-only CSW */
1665 csw = (void *)bh->buf;
1667 csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
1668 csw->Tag = common->tag;
1669 csw->Residue = cpu_to_le32(common->residue);
1670 csw->Status = status;
1672 bh->inreq->length = US_BULK_CS_WRAP_LEN;
1673 bh->inreq->zero = 0;
1674 if (!start_in_transfer(common, bh))
1675 /* Don't know what to do if common->fsg is NULL */
1678 common->next_buffhd_to_fill = bh->next;
1683 /*-------------------------------------------------------------------------*/
1686 * Check whether the command is properly formed and whether its data size
1687 * and direction agree with the values we already have.
1689 static int check_command(struct fsg_common *common, int cmnd_size,
1690 enum data_direction data_dir, unsigned int mask,
1691 int needs_medium, const char *name)
1694 unsigned int lun = common->cmnd[1] >> 5;
1695 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1697 struct fsg_lun *curlun;
1700 if (common->data_dir != DATA_DIR_UNKNOWN)
1701 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1703 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1704 name, cmnd_size, dirletter[(int) data_dir],
1705 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1708 * We can't reply at all until we know the correct data direction
1711 if (common->data_size_from_cmnd == 0)
1712 data_dir = DATA_DIR_NONE;
1713 if (common->data_size < common->data_size_from_cmnd) {
1715 * Host data size < Device data size is a phase error.
1716 * Carry out the command, but only transfer as much as
1719 common->data_size_from_cmnd = common->data_size;
1720 common->phase_error = 1;
1722 common->residue = common->data_size;
1723 common->usb_amount_left = common->data_size;
1725 /* Conflicting data directions is a phase error */
1726 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1727 common->phase_error = 1;
1731 /* Verify the length of the command itself */
1732 if (cmnd_size != common->cmnd_size) {
1735 * Special case workaround: There are plenty of buggy SCSI
1736 * implementations. Many have issues with cbw->Length
1737 * field passing a wrong command size. For those cases we
1738 * always try to work around the problem by using the length
1739 * sent by the host side provided it is at least as large
1740 * as the correct command length.
1741 * Examples of such cases would be MS-Windows, which issues
1742 * REQUEST SENSE with cbw->Length == 12 where it should
1743 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1744 * REQUEST SENSE with cbw->Length == 10 where it should
1747 if (cmnd_size <= common->cmnd_size) {
1748 DBG(common, "%s is buggy! Expected length %d "
1749 "but we got %d\n", name,
1750 cmnd_size, common->cmnd_size);
1751 cmnd_size = common->cmnd_size;
1753 common->phase_error = 1;
1758 /* Check that the LUN values are consistent */
1759 if (common->lun != lun)
1760 DBG(common, "using LUN %u from CBW, not LUN %u from CDB\n",
1764 curlun = common->curlun;
1766 if (common->cmnd[0] != REQUEST_SENSE) {
1767 curlun->sense_data = SS_NO_SENSE;
1768 curlun->sense_data_info = 0;
1769 curlun->info_valid = 0;
1772 common->bad_lun_okay = 0;
1775 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1776 * to use unsupported LUNs; all others may not.
1778 if (common->cmnd[0] != INQUIRY &&
1779 common->cmnd[0] != REQUEST_SENSE) {
1780 DBG(common, "unsupported LUN %u\n", common->lun);
1786 * If a unit attention condition exists, only INQUIRY and
1787 * REQUEST SENSE commands are allowed; anything else must fail.
1789 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1790 common->cmnd[0] != INQUIRY &&
1791 common->cmnd[0] != REQUEST_SENSE) {
1792 curlun->sense_data = curlun->unit_attention_data;
1793 curlun->unit_attention_data = SS_NO_SENSE;
1797 /* Check that only command bytes listed in the mask are non-zero */
1798 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1799 for (i = 1; i < cmnd_size; ++i) {
1800 if (common->cmnd[i] && !(mask & (1 << i))) {
1802 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1807 /* If the medium isn't mounted and the command needs to access
1808 * it, return an error. */
1809 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1810 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1817 /* wrapper of check_command for data size in blocks handling */
1818 static int check_command_size_in_blocks(struct fsg_common *common,
1819 int cmnd_size, enum data_direction data_dir,
1820 unsigned int mask, int needs_medium, const char *name)
1823 common->data_size_from_cmnd <<= common->curlun->blkbits;
1824 return check_command(common, cmnd_size, data_dir,
1825 mask, needs_medium, name);
1828 static int do_scsi_command(struct fsg_common *common)
1830 struct fsg_buffhd *bh;
1832 int reply = -EINVAL;
1834 static char unknown[16];
1838 /* Wait for the next buffer to become available for data or status */
1839 bh = common->next_buffhd_to_fill;
1840 common->next_buffhd_to_drain = bh;
1841 while (bh->state != BUF_STATE_EMPTY) {
1842 rc = sleep_thread(common);
1846 common->phase_error = 0;
1847 common->short_packet_received = 0;
1849 down_read(&common->filesem); /* We're using the backing file */
1850 switch (common->cmnd[0]) {
1853 common->data_size_from_cmnd = common->cmnd[4];
1854 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1858 reply = do_inquiry(common, bh);
1862 common->data_size_from_cmnd = common->cmnd[4];
1863 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1867 reply = do_mode_select(common, bh);
1870 case MODE_SELECT_10:
1871 common->data_size_from_cmnd =
1872 get_unaligned_be16(&common->cmnd[7]);
1873 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1877 reply = do_mode_select(common, bh);
1881 common->data_size_from_cmnd = common->cmnd[4];
1882 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1883 (1<<1) | (1<<2) | (1<<4), 0,
1886 reply = do_mode_sense(common, bh);
1890 common->data_size_from_cmnd =
1891 get_unaligned_be16(&common->cmnd[7]);
1892 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1893 (1<<1) | (1<<2) | (3<<7), 0,
1896 reply = do_mode_sense(common, bh);
1899 case ALLOW_MEDIUM_REMOVAL:
1900 common->data_size_from_cmnd = 0;
1901 reply = check_command(common, 6, DATA_DIR_NONE,
1903 "PREVENT-ALLOW MEDIUM REMOVAL");
1905 reply = do_prevent_allow(common);
1909 i = common->cmnd[4];
1910 common->data_size_from_cmnd = (i == 0) ? 256 : i;
1911 reply = check_command_size_in_blocks(common, 6,
1916 reply = do_read(common);
1920 common->data_size_from_cmnd =
1921 get_unaligned_be16(&common->cmnd[7]);
1922 reply = check_command_size_in_blocks(common, 10,
1924 (1<<1) | (0xf<<2) | (3<<7), 1,
1927 reply = do_read(common);
1931 common->data_size_from_cmnd =
1932 get_unaligned_be32(&common->cmnd[6]);
1933 reply = check_command_size_in_blocks(common, 12,
1935 (1<<1) | (0xf<<2) | (0xf<<6), 1,
1938 reply = do_read(common);
1942 common->data_size_from_cmnd = 8;
1943 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1944 (0xf<<2) | (1<<8), 1,
1947 reply = do_read_capacity(common, bh);
1951 if (!common->curlun || !common->curlun->cdrom)
1953 common->data_size_from_cmnd =
1954 get_unaligned_be16(&common->cmnd[7]);
1955 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1956 (3<<7) | (0x1f<<1), 1,
1959 reply = do_read_header(common, bh);
1963 if (!common->curlun || !common->curlun->cdrom)
1965 common->data_size_from_cmnd =
1966 get_unaligned_be16(&common->cmnd[7]);
1967 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1971 reply = do_read_toc(common, bh);
1974 case READ_FORMAT_CAPACITIES:
1975 common->data_size_from_cmnd =
1976 get_unaligned_be16(&common->cmnd[7]);
1977 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1979 "READ FORMAT CAPACITIES");
1981 reply = do_read_format_capacities(common, bh);
1985 common->data_size_from_cmnd = common->cmnd[4];
1986 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1990 reply = do_request_sense(common, bh);
1994 common->data_size_from_cmnd = 0;
1995 reply = check_command(common, 6, DATA_DIR_NONE,
1999 reply = do_start_stop(common);
2002 case SYNCHRONIZE_CACHE:
2003 common->data_size_from_cmnd = 0;
2004 reply = check_command(common, 10, DATA_DIR_NONE,
2005 (0xf<<2) | (3<<7), 1,
2006 "SYNCHRONIZE CACHE");
2008 reply = do_synchronize_cache(common);
2011 case TEST_UNIT_READY:
2012 common->data_size_from_cmnd = 0;
2013 reply = check_command(common, 6, DATA_DIR_NONE,
2019 * Although optional, this command is used by MS-Windows. We
2020 * support a minimal version: BytChk must be 0.
2023 common->data_size_from_cmnd = 0;
2024 reply = check_command(common, 10, DATA_DIR_NONE,
2025 (1<<1) | (0xf<<2) | (3<<7), 1,
2028 reply = do_verify(common);
2032 i = common->cmnd[4];
2033 common->data_size_from_cmnd = (i == 0) ? 256 : i;
2034 reply = check_command_size_in_blocks(common, 6,
2039 reply = do_write(common);
2043 common->data_size_from_cmnd =
2044 get_unaligned_be16(&common->cmnd[7]);
2045 reply = check_command_size_in_blocks(common, 10,
2047 (1<<1) | (0xf<<2) | (3<<7), 1,
2050 reply = do_write(common);
2054 common->data_size_from_cmnd =
2055 get_unaligned_be32(&common->cmnd[6]);
2056 reply = check_command_size_in_blocks(common, 12,
2058 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2061 reply = do_write(common);
2065 * Some mandatory commands that we recognize but don't implement.
2066 * They don't mean much in this setting. It's left as an exercise
2067 * for anyone interested to implement RESERVE and RELEASE in terms
2073 case SEND_DIAGNOSTIC:
2078 common->data_size_from_cmnd = 0;
2079 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2080 reply = check_command(common, common->cmnd_size,
2081 DATA_DIR_UNKNOWN, ~0, 0, unknown);
2083 common->curlun->sense_data = SS_INVALID_COMMAND;
2088 up_read(&common->filesem);
2090 if (reply == -EINTR || signal_pending(current))
2093 /* Set up the single reply buffer for finish_reply() */
2094 if (reply == -EINVAL)
2095 reply = 0; /* Error reply length */
2096 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2097 reply = min((u32)reply, common->data_size_from_cmnd);
2098 bh->inreq->length = reply;
2099 bh->state = BUF_STATE_FULL;
2100 common->residue -= reply;
2101 } /* Otherwise it's already set */
2107 /*-------------------------------------------------------------------------*/
2109 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2111 struct usb_request *req = bh->outreq;
2112 struct bulk_cb_wrap *cbw = req->buf;
2113 struct fsg_common *common = fsg->common;
2115 /* Was this a real packet? Should it be ignored? */
2116 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2119 /* Is the CBW valid? */
2120 if (req->actual != US_BULK_CB_WRAP_LEN ||
2121 cbw->Signature != cpu_to_le32(
2123 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2125 le32_to_cpu(cbw->Signature));
2128 * The Bulk-only spec says we MUST stall the IN endpoint
2129 * (6.6.1), so it's unavoidable. It also says we must
2130 * retain this state until the next reset, but there's
2131 * no way to tell the controller driver it should ignore
2132 * Clear-Feature(HALT) requests.
2134 * We aren't required to halt the OUT endpoint; instead
2135 * we can simply accept and discard any data received
2136 * until the next reset.
2138 wedge_bulk_in_endpoint(fsg);
2139 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2143 /* Is the CBW meaningful? */
2144 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~US_BULK_FLAG_IN ||
2145 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2146 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2148 cbw->Lun, cbw->Flags, cbw->Length);
2151 * We can do anything we want here, so let's stall the
2152 * bulk pipes if we are allowed to.
2154 if (common->can_stall) {
2155 fsg_set_halt(fsg, fsg->bulk_out);
2156 halt_bulk_in_endpoint(fsg);
2161 /* Save the command for later */
2162 common->cmnd_size = cbw->Length;
2163 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2164 if (cbw->Flags & US_BULK_FLAG_IN)
2165 common->data_dir = DATA_DIR_TO_HOST;
2167 common->data_dir = DATA_DIR_FROM_HOST;
2168 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2169 if (common->data_size == 0)
2170 common->data_dir = DATA_DIR_NONE;
2171 common->lun = cbw->Lun;
2172 if (common->lun < common->nluns)
2173 common->curlun = &common->luns[common->lun];
2175 common->curlun = NULL;
2176 common->tag = cbw->Tag;
2180 static int get_next_command(struct fsg_common *common)
2182 struct fsg_buffhd *bh;
2185 /* Wait for the next buffer to become available */
2186 bh = common->next_buffhd_to_fill;
2187 while (bh->state != BUF_STATE_EMPTY) {
2188 rc = sleep_thread(common);
2193 /* Queue a request to read a Bulk-only CBW */
2194 set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
2195 if (!start_out_transfer(common, bh))
2196 /* Don't know what to do if common->fsg is NULL */
2200 * We will drain the buffer in software, which means we
2201 * can reuse it for the next filling. No need to advance
2202 * next_buffhd_to_fill.
2205 /* Wait for the CBW to arrive */
2206 while (bh->state != BUF_STATE_FULL) {
2207 rc = sleep_thread(common);
2212 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2213 bh->state = BUF_STATE_EMPTY;
2219 /*-------------------------------------------------------------------------*/
2221 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2222 struct usb_request **preq)
2224 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2227 ERROR(common, "can't allocate request for %s\n", ep->name);
2231 /* Reset interface setting and re-init endpoint state (toggle etc). */
2232 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2234 struct fsg_dev *fsg;
2237 if (common->running)
2238 DBG(common, "reset interface\n");
2241 /* Deallocate the requests */
2245 for (i = 0; i < fsg_num_buffers; ++i) {
2246 struct fsg_buffhd *bh = &common->buffhds[i];
2249 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2253 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2258 /* Disable the endpoints */
2259 if (fsg->bulk_in_enabled) {
2260 usb_ep_disable(fsg->bulk_in);
2261 fsg->bulk_in_enabled = 0;
2263 if (fsg->bulk_out_enabled) {
2264 usb_ep_disable(fsg->bulk_out);
2265 fsg->bulk_out_enabled = 0;
2269 wake_up(&common->fsg_wait);
2272 common->running = 0;
2276 common->fsg = new_fsg;
2279 /* Enable the endpoints */
2280 rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
2283 rc = usb_ep_enable(fsg->bulk_in);
2286 fsg->bulk_in->driver_data = common;
2287 fsg->bulk_in_enabled = 1;
2289 rc = config_ep_by_speed(common->gadget, &(fsg->function),
2293 rc = usb_ep_enable(fsg->bulk_out);
2296 fsg->bulk_out->driver_data = common;
2297 fsg->bulk_out_enabled = 1;
2298 common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc);
2299 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2301 /* Allocate the requests */
2302 for (i = 0; i < fsg_num_buffers; ++i) {
2303 struct fsg_buffhd *bh = &common->buffhds[i];
2305 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2308 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2311 bh->inreq->buf = bh->outreq->buf = bh->buf;
2312 bh->inreq->context = bh->outreq->context = bh;
2313 bh->inreq->complete = bulk_in_complete;
2314 bh->outreq->complete = bulk_out_complete;
2317 common->running = 1;
2318 for (i = 0; i < common->nluns; ++i)
2319 common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
2324 /****************************** ALT CONFIGS ******************************/
2326 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2328 struct fsg_dev *fsg = fsg_from_func(f);
2329 fsg->common->new_fsg = fsg;
2330 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2331 return USB_GADGET_DELAYED_STATUS;
2334 static void fsg_disable(struct usb_function *f)
2336 struct fsg_dev *fsg = fsg_from_func(f);
2337 fsg->common->new_fsg = NULL;
2338 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2342 /*-------------------------------------------------------------------------*/
2344 static void handle_exception(struct fsg_common *common)
2348 struct fsg_buffhd *bh;
2349 enum fsg_state old_state;
2350 struct fsg_lun *curlun;
2351 unsigned int exception_req_tag;
2354 * Clear the existing signals. Anything but SIGUSR1 is converted
2355 * into a high-priority EXIT exception.
2359 dequeue_signal_lock(current, ¤t->blocked, &info);
2362 if (sig != SIGUSR1) {
2363 if (common->state < FSG_STATE_EXIT)
2364 DBG(common, "Main thread exiting on signal\n");
2365 raise_exception(common, FSG_STATE_EXIT);
2369 /* Cancel all the pending transfers */
2370 if (likely(common->fsg)) {
2371 for (i = 0; i < fsg_num_buffers; ++i) {
2372 bh = &common->buffhds[i];
2374 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2375 if (bh->outreq_busy)
2376 usb_ep_dequeue(common->fsg->bulk_out,
2380 /* Wait until everything is idle */
2383 for (i = 0; i < fsg_num_buffers; ++i) {
2384 bh = &common->buffhds[i];
2385 num_active += bh->inreq_busy + bh->outreq_busy;
2387 if (num_active == 0)
2389 if (sleep_thread(common))
2393 /* Clear out the controller's fifos */
2394 if (common->fsg->bulk_in_enabled)
2395 usb_ep_fifo_flush(common->fsg->bulk_in);
2396 if (common->fsg->bulk_out_enabled)
2397 usb_ep_fifo_flush(common->fsg->bulk_out);
2401 * Reset the I/O buffer states and pointers, the SCSI
2402 * state, and the exception. Then invoke the handler.
2404 spin_lock_irq(&common->lock);
2406 for (i = 0; i < fsg_num_buffers; ++i) {
2407 bh = &common->buffhds[i];
2408 bh->state = BUF_STATE_EMPTY;
2410 common->next_buffhd_to_fill = &common->buffhds[0];
2411 common->next_buffhd_to_drain = &common->buffhds[0];
2412 exception_req_tag = common->exception_req_tag;
2413 old_state = common->state;
2415 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2416 common->state = FSG_STATE_STATUS_PHASE;
2418 for (i = 0; i < common->nluns; ++i) {
2419 curlun = &common->luns[i];
2420 curlun->prevent_medium_removal = 0;
2421 curlun->sense_data = SS_NO_SENSE;
2422 curlun->unit_attention_data = SS_NO_SENSE;
2423 curlun->sense_data_info = 0;
2424 curlun->info_valid = 0;
2426 common->state = FSG_STATE_IDLE;
2428 spin_unlock_irq(&common->lock);
2430 /* Carry out any extra actions required for the exception */
2431 switch (old_state) {
2432 case FSG_STATE_ABORT_BULK_OUT:
2433 send_status(common);
2434 spin_lock_irq(&common->lock);
2435 if (common->state == FSG_STATE_STATUS_PHASE)
2436 common->state = FSG_STATE_IDLE;
2437 spin_unlock_irq(&common->lock);
2440 case FSG_STATE_RESET:
2442 * In case we were forced against our will to halt a
2443 * bulk endpoint, clear the halt now. (The SuperH UDC
2446 if (!fsg_is_set(common))
2448 if (test_and_clear_bit(IGNORE_BULK_OUT,
2449 &common->fsg->atomic_bitflags))
2450 usb_ep_clear_halt(common->fsg->bulk_in);
2452 if (common->ep0_req_tag == exception_req_tag)
2453 ep0_queue(common); /* Complete the status stage */
2456 * Technically this should go here, but it would only be
2457 * a waste of time. Ditto for the INTERFACE_CHANGE and
2458 * CONFIG_CHANGE cases.
2460 /* for (i = 0; i < common->nluns; ++i) */
2461 /* common->luns[i].unit_attention_data = */
2462 /* SS_RESET_OCCURRED; */
2465 case FSG_STATE_CONFIG_CHANGE:
2466 do_set_interface(common, common->new_fsg);
2467 if (common->new_fsg)
2468 usb_composite_setup_continue(common->cdev);
2471 case FSG_STATE_EXIT:
2472 case FSG_STATE_TERMINATED:
2473 do_set_interface(common, NULL); /* Free resources */
2474 spin_lock_irq(&common->lock);
2475 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2476 spin_unlock_irq(&common->lock);
2479 case FSG_STATE_INTERFACE_CHANGE:
2480 case FSG_STATE_DISCONNECT:
2481 case FSG_STATE_COMMAND_PHASE:
2482 case FSG_STATE_DATA_PHASE:
2483 case FSG_STATE_STATUS_PHASE:
2484 case FSG_STATE_IDLE:
2490 /*-------------------------------------------------------------------------*/
2492 static int fsg_main_thread(void *common_)
2494 struct fsg_common *common = common_;
2497 * Allow the thread to be killed by a signal, but set the signal mask
2498 * to block everything but INT, TERM, KILL, and USR1.
2500 allow_signal(SIGINT);
2501 allow_signal(SIGTERM);
2502 allow_signal(SIGKILL);
2503 allow_signal(SIGUSR1);
2505 /* Allow the thread to be frozen */
2509 * Arrange for userspace references to be interpreted as kernel
2510 * pointers. That way we can pass a kernel pointer to a routine
2511 * that expects a __user pointer and it will work okay.
2516 while (common->state != FSG_STATE_TERMINATED) {
2517 if (exception_in_progress(common) || signal_pending(current)) {
2518 handle_exception(common);
2522 if (!common->running) {
2523 sleep_thread(common);
2527 if (get_next_command(common))
2530 spin_lock_irq(&common->lock);
2531 if (!exception_in_progress(common))
2532 common->state = FSG_STATE_DATA_PHASE;
2533 spin_unlock_irq(&common->lock);
2535 if (do_scsi_command(common) || finish_reply(common))
2538 spin_lock_irq(&common->lock);
2539 if (!exception_in_progress(common))
2540 common->state = FSG_STATE_STATUS_PHASE;
2541 spin_unlock_irq(&common->lock);
2543 if (send_status(common))
2546 spin_lock_irq(&common->lock);
2547 if (!exception_in_progress(common))
2548 common->state = FSG_STATE_IDLE;
2549 spin_unlock_irq(&common->lock);
2552 spin_lock_irq(&common->lock);
2553 common->thread_task = NULL;
2554 spin_unlock_irq(&common->lock);
2556 if (!common->ops || !common->ops->thread_exits
2557 || common->ops->thread_exits(common) < 0) {
2558 struct fsg_lun *curlun = common->luns;
2559 unsigned i = common->nluns;
2561 down_write(&common->filesem);
2562 for (; i--; ++curlun) {
2563 if (!fsg_lun_is_open(curlun))
2566 fsg_lun_close(curlun);
2567 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
2569 up_write(&common->filesem);
2572 /* Let fsg_unbind() know the thread has exited */
2573 complete_and_exit(&common->thread_notifier, 0);
2577 /*************************** DEVICE ATTRIBUTES ***************************/
2579 static DEVICE_ATTR(ro, 0644, fsg_show_ro, fsg_store_ro);
2580 static DEVICE_ATTR(nofua, 0644, fsg_show_nofua, fsg_store_nofua);
2581 static DEVICE_ATTR(file, 0644, fsg_show_file, fsg_store_file);
2583 static struct device_attribute dev_attr_ro_cdrom =
2584 __ATTR(ro, 0444, fsg_show_ro, NULL);
2585 static struct device_attribute dev_attr_file_nonremovable =
2586 __ATTR(file, 0444, fsg_show_file, NULL);
2589 /****************************** FSG COMMON ******************************/
2591 static void fsg_common_release(struct kref *ref);
2593 static void fsg_lun_release(struct device *dev)
2595 /* Nothing needs to be done */
2598 static inline void fsg_common_get(struct fsg_common *common)
2600 kref_get(&common->ref);
2603 static inline void fsg_common_put(struct fsg_common *common)
2605 kref_put(&common->ref, fsg_common_release);
2608 static struct fsg_common *fsg_common_init(struct fsg_common *common,
2609 struct usb_composite_dev *cdev,
2610 struct fsg_config *cfg)
2612 struct usb_gadget *gadget = cdev->gadget;
2613 struct fsg_buffhd *bh;
2614 struct fsg_lun *curlun;
2615 struct fsg_lun_config *lcfg;
2619 rc = fsg_num_buffers_validate();
2623 /* Find out how many LUNs there should be */
2625 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2626 dev_err(&gadget->dev, "invalid number of LUNs: %u\n", nluns);
2627 return ERR_PTR(-EINVAL);
2632 common = kzalloc(sizeof *common, GFP_KERNEL);
2634 return ERR_PTR(-ENOMEM);
2635 common->free_storage_on_release = 1;
2637 memset(common, 0, sizeof *common);
2638 common->free_storage_on_release = 0;
2641 common->buffhds = kcalloc(fsg_num_buffers,
2642 sizeof *(common->buffhds), GFP_KERNEL);
2643 if (!common->buffhds) {
2644 if (common->free_storage_on_release)
2646 return ERR_PTR(-ENOMEM);
2649 common->ops = cfg->ops;
2650 common->private_data = cfg->private_data;
2652 common->gadget = gadget;
2653 common->ep0 = gadget->ep0;
2654 common->ep0req = cdev->req;
2655 common->cdev = cdev;
2657 /* Maybe allocate device-global string IDs, and patch descriptors */
2658 if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
2659 rc = usb_string_id(cdev);
2660 if (unlikely(rc < 0))
2662 fsg_strings[FSG_STRING_INTERFACE].id = rc;
2663 fsg_intf_desc.iInterface = rc;
2667 * Create the LUNs, open their backing files, and register the
2668 * LUN devices in sysfs.
2670 curlun = kcalloc(nluns, sizeof(*curlun), GFP_KERNEL);
2671 if (unlikely(!curlun)) {
2675 common->luns = curlun;
2677 init_rwsem(&common->filesem);
2679 for (i = 0, lcfg = cfg->luns; i < nluns; ++i, ++curlun, ++lcfg) {
2680 curlun->cdrom = !!lcfg->cdrom;
2681 curlun->ro = lcfg->cdrom || lcfg->ro;
2682 curlun->initially_ro = curlun->ro;
2683 curlun->removable = lcfg->removable;
2684 curlun->dev.release = fsg_lun_release;
2685 curlun->dev.parent = &gadget->dev;
2686 /* curlun->dev.driver = &fsg_driver.driver; XXX */
2687 dev_set_drvdata(&curlun->dev, &common->filesem);
2688 dev_set_name(&curlun->dev, "lun%d", i);
2690 rc = device_register(&curlun->dev);
2692 INFO(common, "failed to register LUN%d: %d\n", i, rc);
2694 put_device(&curlun->dev);
2698 rc = device_create_file(&curlun->dev,
2700 ? &dev_attr_ro_cdrom
2704 rc = device_create_file(&curlun->dev,
2707 : &dev_attr_file_nonremovable);
2710 rc = device_create_file(&curlun->dev, &dev_attr_nofua);
2714 if (lcfg->filename) {
2715 rc = fsg_lun_open(curlun, lcfg->filename);
2718 } else if (!curlun->removable) {
2719 ERROR(common, "no file given for LUN%d\n", i);
2724 common->nluns = nluns;
2726 /* Data buffers cyclic list */
2727 bh = common->buffhds;
2728 i = fsg_num_buffers;
2729 goto buffhds_first_it;
2734 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2735 if (unlikely(!bh->buf)) {
2740 bh->next = common->buffhds;
2742 /* Prepare inquiryString */
2743 i = get_default_bcdDevice();
2744 snprintf(common->inquiry_string, sizeof common->inquiry_string,
2745 "%-8s%-16s%04x", cfg->vendor_name ?: "Linux",
2746 /* Assume product name dependent on the first LUN */
2747 cfg->product_name ?: (common->luns->cdrom
2748 ? "File-Stor Gadget"
2749 : "File-CD Gadget"),
2753 * Some peripheral controllers are known not to be able to
2754 * halt bulk endpoints correctly. If one of them is present,
2757 common->can_stall = cfg->can_stall &&
2758 !(gadget_is_at91(common->gadget));
2760 spin_lock_init(&common->lock);
2761 kref_init(&common->ref);
2763 /* Tell the thread to start working */
2764 common->thread_task =
2765 kthread_create(fsg_main_thread, common, "file-storage");
2766 if (IS_ERR(common->thread_task)) {
2767 rc = PTR_ERR(common->thread_task);
2770 init_completion(&common->thread_notifier);
2771 init_waitqueue_head(&common->fsg_wait);
2774 INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2775 INFO(common, "Number of LUNs=%d\n", common->nluns);
2777 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2778 for (i = 0, nluns = common->nluns, curlun = common->luns;
2781 char *p = "(no medium)";
2782 if (fsg_lun_is_open(curlun)) {
2785 p = d_path(&curlun->filp->f_path,
2791 LINFO(curlun, "LUN: %s%s%sfile: %s\n",
2792 curlun->removable ? "removable " : "",
2793 curlun->ro ? "read only " : "",
2794 curlun->cdrom ? "CD-ROM " : "",
2799 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
2801 wake_up_process(common->thread_task);
2806 common->nluns = i + 1;
2808 common->state = FSG_STATE_TERMINATED; /* The thread is dead */
2809 /* Call fsg_common_release() directly, ref might be not initialised. */
2810 fsg_common_release(&common->ref);
2814 static void fsg_common_release(struct kref *ref)
2816 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
2818 /* If the thread isn't already dead, tell it to exit now */
2819 if (common->state != FSG_STATE_TERMINATED) {
2820 raise_exception(common, FSG_STATE_EXIT);
2821 wait_for_completion(&common->thread_notifier);
2824 if (likely(common->luns)) {
2825 struct fsg_lun *lun = common->luns;
2826 unsigned i = common->nluns;
2828 /* In error recovery common->nluns may be zero. */
2829 for (; i; --i, ++lun) {
2830 device_remove_file(&lun->dev, &dev_attr_nofua);
2831 device_remove_file(&lun->dev,
2833 ? &dev_attr_ro_cdrom
2835 device_remove_file(&lun->dev,
2838 : &dev_attr_file_nonremovable);
2840 device_unregister(&lun->dev);
2843 kfree(common->luns);
2847 struct fsg_buffhd *bh = common->buffhds;
2848 unsigned i = fsg_num_buffers;
2851 } while (++bh, --i);
2854 kfree(common->buffhds);
2855 if (common->free_storage_on_release)
2860 /*-------------------------------------------------------------------------*/
2862 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
2864 struct fsg_dev *fsg = fsg_from_func(f);
2865 struct fsg_common *common = fsg->common;
2867 DBG(fsg, "unbind\n");
2868 if (fsg->common->fsg == fsg) {
2869 fsg->common->new_fsg = NULL;
2870 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2871 /* FIXME: make interruptible or killable somehow? */
2872 wait_event(common->fsg_wait, common->fsg != fsg);
2875 fsg_common_put(common);
2876 usb_free_all_descriptors(&fsg->function);
2880 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
2882 struct fsg_dev *fsg = fsg_from_func(f);
2883 struct usb_gadget *gadget = c->cdev->gadget;
2889 fsg->gadget = gadget;
2892 i = usb_interface_id(c, f);
2895 fsg_intf_desc.bInterfaceNumber = i;
2896 fsg->interface_number = i;
2898 /* Find all the endpoints we will use */
2899 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
2902 ep->driver_data = fsg->common; /* claim the endpoint */
2905 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
2908 ep->driver_data = fsg->common; /* claim the endpoint */
2911 /* Assume endpoint addresses are the same for both speeds */
2912 fsg_hs_bulk_in_desc.bEndpointAddress =
2913 fsg_fs_bulk_in_desc.bEndpointAddress;
2914 fsg_hs_bulk_out_desc.bEndpointAddress =
2915 fsg_fs_bulk_out_desc.bEndpointAddress;
2917 /* Calculate bMaxBurst, we know packet size is 1024 */
2918 max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15);
2920 fsg_ss_bulk_in_desc.bEndpointAddress =
2921 fsg_fs_bulk_in_desc.bEndpointAddress;
2922 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
2924 fsg_ss_bulk_out_desc.bEndpointAddress =
2925 fsg_fs_bulk_out_desc.bEndpointAddress;
2926 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
2928 ret = usb_assign_descriptors(f, fsg_fs_function, fsg_hs_function,
2936 ERROR(fsg, "unable to autoconfigure all endpoints\n");
2940 /****************************** ADD FUNCTION ******************************/
2942 static struct usb_gadget_strings *fsg_strings_array[] = {
2947 static int fsg_bind_config(struct usb_composite_dev *cdev,
2948 struct usb_configuration *c,
2949 struct fsg_common *common)
2951 struct fsg_dev *fsg;
2954 fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
2958 fsg->function.name = FSG_DRIVER_DESC;
2959 fsg->function.strings = fsg_strings_array;
2960 fsg->function.bind = fsg_bind;
2961 fsg->function.unbind = fsg_unbind;
2962 fsg->function.setup = fsg_setup;
2963 fsg->function.set_alt = fsg_set_alt;
2964 fsg->function.disable = fsg_disable;
2966 fsg->common = common;
2968 * Our caller holds a reference to common structure so we
2969 * don't have to be worry about it being freed until we return
2970 * from this function. So instead of incrementing counter now
2971 * and decrement in error recovery we increment it only when
2972 * call to usb_add_function() was successful.
2975 rc = usb_add_function(c, &fsg->function);
2979 fsg_common_get(fsg->common);
2984 /************************* Module parameters *************************/
2986 struct fsg_module_parameters {
2987 char *file[FSG_MAX_LUNS];
2988 bool ro[FSG_MAX_LUNS];
2989 bool removable[FSG_MAX_LUNS];
2990 bool cdrom[FSG_MAX_LUNS];
2991 bool nofua[FSG_MAX_LUNS];
2993 unsigned int file_count, ro_count, removable_count, cdrom_count;
2994 unsigned int nofua_count;
2995 unsigned int luns; /* nluns */
2996 bool stall; /* can_stall */
2999 #define _FSG_MODULE_PARAM_ARRAY(prefix, params, name, type, desc) \
3000 module_param_array_named(prefix ## name, params.name, type, \
3001 &prefix ## params.name ## _count, \
3003 MODULE_PARM_DESC(prefix ## name, desc)
3005 #define _FSG_MODULE_PARAM(prefix, params, name, type, desc) \
3006 module_param_named(prefix ## name, params.name, type, \
3008 MODULE_PARM_DESC(prefix ## name, desc)
3010 #define FSG_MODULE_PARAMETERS(prefix, params) \
3011 _FSG_MODULE_PARAM_ARRAY(prefix, params, file, charp, \
3012 "names of backing files or devices"); \
3013 _FSG_MODULE_PARAM_ARRAY(prefix, params, ro, bool, \
3014 "true to force read-only"); \
3015 _FSG_MODULE_PARAM_ARRAY(prefix, params, removable, bool, \
3016 "true to simulate removable media"); \
3017 _FSG_MODULE_PARAM_ARRAY(prefix, params, cdrom, bool, \
3018 "true to simulate CD-ROM instead of disk"); \
3019 _FSG_MODULE_PARAM_ARRAY(prefix, params, nofua, bool, \
3020 "true to ignore SCSI WRITE(10,12) FUA bit"); \
3021 _FSG_MODULE_PARAM(prefix, params, luns, uint, \
3022 "number of LUNs"); \
3023 _FSG_MODULE_PARAM(prefix, params, stall, bool, \
3024 "false to prevent bulk stalls")
3027 fsg_config_from_params(struct fsg_config *cfg,
3028 const struct fsg_module_parameters *params)
3030 struct fsg_lun_config *lun;
3033 /* Configure LUNs */
3035 min(params->luns ?: (params->file_count ?: 1u),
3036 (unsigned)FSG_MAX_LUNS);
3037 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3038 lun->ro = !!params->ro[i];
3039 lun->cdrom = !!params->cdrom[i];
3040 lun->removable = !!params->removable[i];
3042 params->file_count > i && params->file[i][0]
3047 /* Let MSF use defaults */
3048 cfg->vendor_name = 0;
3049 cfg->product_name = 0;
3052 cfg->private_data = NULL;
3055 cfg->can_stall = params->stall;
3058 static inline struct fsg_common *
3059 fsg_common_from_params(struct fsg_common *common,
3060 struct usb_composite_dev *cdev,
3061 const struct fsg_module_parameters *params)
3062 __attribute__((unused));
3063 static inline struct fsg_common *
3064 fsg_common_from_params(struct fsg_common *common,
3065 struct usb_composite_dev *cdev,
3066 const struct fsg_module_parameters *params)
3068 struct fsg_config cfg;
3069 fsg_config_from_params(&cfg, params);
3070 return fsg_common_init(common, cdev, &cfg);