/drivers/usb/gadget/f_mass_storage.c
C | 1659 lines | 958 code | 212 blank | 489 comment | 213 complexity | 60cbd6d7addea6430ce036db0f82d58a MD5 | raw file
- /*
- * f_mass_storage.c -- Mass Storage USB Composite Function
- *
- * Copyright (C) 2003-2008 Alan Stern
- * Copyright (C) 2009 Samsung Electronics
- * Author: Michal Nazarewicz <m.nazarewicz@samsung.com>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions, and the following disclaimer,
- * without modification.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. The names of the above-listed copyright holders may not be used
- * to endorse or promote products derived from this software without
- * specific prior written permission.
- *
- * ALTERNATIVELY, this software may be distributed under the terms of the
- * GNU General Public License ("GPL") as published by the Free Software
- * Foundation, either version 2 of that License or (at your option) any
- * later version.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
- * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
- * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
- * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
- * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
- * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
- /*
- * The Mass Storage Function acts as a USB Mass Storage device,
- * appearing to the host as a disk drive or as a CD-ROM drive. In
- * addition to providing an example of a genuinely useful composite
- * function for a USB device, it also illustrates a technique of
- * double-buffering for increased throughput.
- *
- * Function supports multiple logical units (LUNs). Backing storage
- * for each LUN is provided by a regular file or a block device.
- * Access for each LUN can be limited to read-only. Moreover, the
- * function can indicate that LUN is removable and/or CD-ROM. (The
- * later implies read-only access.)
- *
- * MSF is configured by specifying a fsg_config structure. It has the
- * following fields:
- *
- * nluns Number of LUNs function have (anywhere from 1
- * to FSG_MAX_LUNS which is 8).
- * luns An array of LUN configuration values. This
- * should be filled for each LUN that
- * function will include (ie. for "nluns"
- * LUNs). Each element of the array has
- * the following fields:
- * ->filename The path to the backing file for the LUN.
- * Required if LUN is not marked as
- * removable.
- * ->ro Flag specifying access to the LUN shall be
- * read-only. This is implied if CD-ROM
- * emulation is enabled as well as when
- * it was impossible to open "filename"
- * in R/W mode.
- * ->removable Flag specifying that LUN shall be indicated as
- * being removable.
- * ->cdrom Flag specifying that LUN shall be reported as
- * being a CD-ROM.
- * ->nofua Flag specifying that FUA flag in SCSI WRITE(10,12)
- * commands for this LUN shall be ignored.
- *
- * lun_name_format A printf-like format for names of the LUN
- * devices. This determines how the
- * directory in sysfs will be named.
- * Unless you are using several MSFs in
- * a single gadget (as opposed to single
- * MSF in many configurations) you may
- * leave it as NULL (in which case
- * "lun%d" will be used). In the format
- * you can use "%d" to index LUNs for
- * MSF's with more than one LUN. (Beware
- * that there is only one integer given
- * as an argument for the format and
- * specifying invalid format may cause
- * unspecified behaviour.)
- * thread_name Name of the kernel thread process used by the
- * MSF. You can safely set it to NULL
- * (in which case default "file-storage"
- * will be used).
- *
- * vendor_name
- * product_name
- * release Information used as a reply to INQUIRY
- * request. To use default set to NULL,
- * NULL, 0xffff respectively. The first
- * field should be 8 and the second 16
- * characters or less.
- *
- * can_stall Set to permit function to halt bulk endpoints.
- * Disabled on some USB devices known not
- * to work correctly. You should set it
- * to true.
- *
- * If "removable" is not set for a LUN then a backing file must be
- * specified. If it is set, then NULL filename means the LUN's medium
- * is not loaded (an empty string as "filename" in the fsg_config
- * structure causes error). The CD-ROM emulation includes a single
- * data track and no audio tracks; hence there need be only one
- * backing file per LUN. Note also that the CD-ROM block length is
- * set to 512 rather than the more common value 2048.
- *
- *
- * MSF includes support for module parameters. If gadget using it
- * decides to use it, the following module parameters will be
- * available:
- *
- * file=filename[,filename...]
- * Names of the files or block devices used for
- * backing storage.
- * ro=b[,b...] Default false, boolean for read-only access.
- * removable=b[,b...]
- * Default true, boolean for removable media.
- * cdrom=b[,b...] Default false, boolean for whether to emulate
- * a CD-ROM drive.
- * nofua=b[,b...] Default false, booleans for ignore FUA flag
- * in SCSI WRITE(10,12) commands
- * luns=N Default N = number of filenames, number of
- * LUNs to support.
- * stall Default determined according to the type of
- * USB device controller (usually true),
- * boolean to permit the driver to halt
- * bulk endpoints.
- *
- * The module parameters may be prefixed with some string. You need
- * to consult gadget's documentation or source to verify whether it is
- * using those module parameters and if it does what are the prefixes
- * (look for FSG_MODULE_PARAMETERS() macro usage, what's inside it is
- * the prefix).
- *
- *
- * Requirements are modest; only a bulk-in and a bulk-out endpoint are
- * needed. The memory requirement amounts to two 16K buffers, size
- * configurable by a parameter. Support is included for both
- * full-speed and high-speed operation.
- *
- * Note that the driver is slightly non-portable in that it assumes a
- * single memory/DMA buffer will be useable for bulk-in, bulk-out, and
- * interrupt-in endpoints. With most device controllers this isn't an
- * issue, but there may be some with hardware restrictions that prevent
- * a buffer from being used by more than one endpoint.
- *
- *
- * The pathnames of the backing files and the ro settings are
- * available in the attribute files "file" and "ro" in the lun<n> (or
- * to be more precise in a directory which name comes from
- * "lun_name_format" option!) subdirectory of the gadget's sysfs
- * directory. If the "removable" option is set, writing to these
- * files will simulate ejecting/loading the medium (writing an empty
- * line means eject) and adjusting a write-enable tab. Changes to the
- * ro setting are not allowed when the medium is loaded or if CD-ROM
- * emulation is being used.
- *
- * When a LUN receive an "eject" SCSI request (Start/Stop Unit),
- * if the LUN is removable, the backing file is released to simulate
- * ejection.
- *
- *
- * This function is heavily based on "File-backed Storage Gadget" by
- * Alan Stern which in turn is heavily based on "Gadget Zero" by David
- * Brownell. The driver's SCSI command interface was based on the
- * "Information technology - Small Computer System Interface - 2"
- * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
- * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
- * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
- * was based on the "Universal Serial Bus Mass Storage Class UFI
- * Command Specification" document, Revision 1.0, December 14, 1998,
- * available at
- * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
- */
- /*
- * Driver Design
- *
- * The MSF is fairly straightforward. There is a main kernel
- * thread that handles most of the work. Interrupt routines field
- * callbacks from the controller driver: bulk- and interrupt-request
- * completion notifications, endpoint-0 events, and disconnect events.
- * Completion events are passed to the main thread by wakeup calls. Many
- * ep0 requests are handled at interrupt time, but SetInterface,
- * SetConfiguration, and device reset requests are forwarded to the
- * thread in the form of "exceptions" using SIGUSR1 signals (since they
- * should interrupt any ongoing file I/O operations).
- *
- * The thread's main routine implements the standard command/data/status
- * parts of a SCSI interaction. It and its subroutines are full of tests
- * for pending signals/exceptions -- all this polling is necessary since
- * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
- * indication that the driver really wants to be running in userspace.)
- * An important point is that so long as the thread is alive it keeps an
- * open reference to the backing file. This will prevent unmounting
- * the backing file's underlying filesystem and could cause problems
- * during system shutdown, for example. To prevent such problems, the
- * thread catches INT, TERM, and KILL signals and converts them into
- * an EXIT exception.
- *
- * In normal operation the main thread is started during the gadget's
- * fsg_bind() callback and stopped during fsg_unbind(). But it can
- * also exit when it receives a signal, and there's no point leaving
- * the gadget running when the thread is dead. At of this moment, MSF
- * provides no way to deregister the gadget when thread dies -- maybe
- * a callback functions is needed.
- *
- * To provide maximum throughput, the driver uses a circular pipeline of
- * buffer heads (struct fsg_buffhd). In principle the pipeline can be
- * arbitrarily long; in practice the benefits don't justify having more
- * than 2 stages (i.e., double buffering). But it helps to think of the
- * pipeline as being a long one. Each buffer head contains a bulk-in and
- * a bulk-out request pointer (since the buffer can be used for both
- * output and input -- directions always are given from the host's
- * point of view) as well as a pointer to the buffer and various state
- * variables.
- *
- * Use of the pipeline follows a simple protocol. There is a variable
- * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
- * At any time that buffer head may still be in use from an earlier
- * request, so each buffer head has a state variable indicating whether
- * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
- * buffer head to be EMPTY, filling the buffer either by file I/O or by
- * USB I/O (during which the buffer head is BUSY), and marking the buffer
- * head FULL when the I/O is complete. Then the buffer will be emptied
- * (again possibly by USB I/O, during which it is marked BUSY) and
- * finally marked EMPTY again (possibly by a completion routine).
- *
- * A module parameter tells the driver to avoid stalling the bulk
- * endpoints wherever the transport specification allows. This is
- * necessary for some UDCs like the SuperH, which cannot reliably clear a
- * halt on a bulk endpoint. However, under certain circumstances the
- * Bulk-only specification requires a stall. In such cases the driver
- * will halt the endpoint and set a flag indicating that it should clear
- * the halt in software during the next device reset. Hopefully this
- * will permit everything to work correctly. Furthermore, although the
- * specification allows the bulk-out endpoint to halt when the host sends
- * too much data, implementing this would cause an unavoidable race.
- * The driver will always use the "no-stall" approach for OUT transfers.
- *
- * One subtle point concerns sending status-stage responses for ep0
- * requests. Some of these requests, such as device reset, can involve
- * interrupting an ongoing file I/O operation, which might take an
- * arbitrarily long time. During that delay the host might give up on
- * the original ep0 request and issue a new one. When that happens the
- * driver should not notify the host about completion of the original
- * request, as the host will no longer be waiting for it. So the driver
- * assigns to each ep0 request a unique tag, and it keeps track of the
- * tag value of the request associated with a long-running exception
- * (device-reset, interface-change, or configuration-change). When the
- * exception handler is finished, the status-stage response is submitted
- * only if the current ep0 request tag is equal to the exception request
- * tag. Thus only the most recently received ep0 request will get a
- * status-stage response.
- *
- * Warning: This driver source file is too long. It ought to be split up
- * into a header file plus about 3 separate .c files, to handle the details
- * of the Gadget, USB Mass Storage, and SCSI protocols.
- */
- /* #define VERBOSE_DEBUG */
- /* #define DUMP_MSGS */
- #include <linux/blkdev.h>
- #include <linux/completion.h>
- #include <linux/dcache.h>
- #include <linux/delay.h>
- #include <linux/device.h>
- #include <linux/fcntl.h>
- #include <linux/file.h>
- #include <linux/fs.h>
- #include <linux/kref.h>
- #include <linux/kthread.h>
- #include <linux/limits.h>
- #include <linux/rwsem.h>
- #include <linux/slab.h>
- #include <linux/spinlock.h>
- #include <linux/string.h>
- #include <linux/freezer.h>
- #include <linux/utsname.h>
- #include <linux/usb/ch9.h>
- #include <linux/usb/gadget.h>
- #include <linux/usb/composite.h>
- #include "gadget_chips.h"
- /*------------------------------------------------------------------------*/
- #define FSG_DRIVER_DESC "Mass Storage Function"
- #define FSG_DRIVER_VERSION "2009/09/11"
- static const char fsg_string_interface[] = "Mass Storage";
- #define FSG_NO_INTR_EP 1
- #define FSG_NO_DEVICE_STRINGS 1
- #define FSG_NO_OTG 1
- #define FSG_NO_INTR_EP 1
- #include "storage_common.c"
- /*-------------------------------------------------------------------------*/
- struct fsg_dev;
- struct fsg_common;
- /* FSF callback functions */
- struct fsg_operations {
- /*
- * Callback function to call when thread exits. If no
- * callback is set or it returns value lower then zero MSF
- * will force eject all LUNs it operates on (including those
- * marked as non-removable or with prevent_medium_removal flag
- * set).
- */
- int (*thread_exits)(struct fsg_common *common);
- /*
- * Called prior to ejection. Negative return means error,
- * zero means to continue with ejection, positive means not to
- * eject.
- */
- int (*pre_eject)(struct fsg_common *common,
- struct fsg_lun *lun, int num);
- /*
- * Called after ejection. Negative return means error, zero
- * or positive is just a success.
- */
- int (*post_eject)(struct fsg_common *common,
- struct fsg_lun *lun, int num);
- };
- /* Data shared by all the FSG instances. */
- struct fsg_common {
- struct usb_gadget *gadget;
- struct usb_composite_dev *cdev;
- struct fsg_dev *fsg, *new_fsg;
- wait_queue_head_t fsg_wait;
- /* filesem protects: backing files in use */
- struct rw_semaphore filesem;
- /* lock protects: state, all the req_busy's */
- spinlock_t lock;
- struct usb_ep *ep0; /* Copy of gadget->ep0 */
- struct usb_request *ep0req; /* Copy of cdev->req */
- unsigned int ep0_req_tag;
- struct fsg_buffhd *next_buffhd_to_fill;
- struct fsg_buffhd *next_buffhd_to_drain;
- struct fsg_buffhd buffhds[FSG_NUM_BUFFERS];
- int cmnd_size;
- u8 cmnd[MAX_COMMAND_SIZE];
- unsigned int nluns;
- unsigned int lun;
- struct fsg_lun *luns;
- struct fsg_lun *curlun;
- unsigned int bulk_out_maxpacket;
- enum fsg_state state; /* For exception handling */
- unsigned int exception_req_tag;
- enum data_direction data_dir;
- u32 data_size;
- u32 data_size_from_cmnd;
- u32 tag;
- u32 residue;
- u32 usb_amount_left;
- unsigned int can_stall:1;
- unsigned int free_storage_on_release:1;
- unsigned int phase_error:1;
- unsigned int short_packet_received:1;
- unsigned int bad_lun_okay:1;
- unsigned int running:1;
- int thread_wakeup_needed;
- struct completion thread_notifier;
- struct task_struct *thread_task;
- /* Callback functions. */
- const struct fsg_operations *ops;
- /* Gadget's private data. */
- void *private_data;
- /*
- * Vendor (8 chars), product (16 chars), release (4
- * hexadecimal digits) and NUL byte
- */
- char inquiry_string[8 + 16 + 4 + 1];
- struct kref ref;
- };
- struct fsg_config {
- unsigned nluns;
- struct fsg_lun_config {
- const char *filename;
- char ro;
- char removable;
- char cdrom;
- char nofua;
- } luns[FSG_MAX_LUNS];
- const char *lun_name_format;
- const char *thread_name;
- /* Callback functions. */
- const struct fsg_operations *ops;
- /* Gadget's private data. */
- void *private_data;
- const char *vendor_name; /* 8 characters or less */
- const char *product_name; /* 16 characters or less */
- u16 release;
- char can_stall;
- };
- struct fsg_dev {
- struct usb_function function;
- struct usb_gadget *gadget; /* Copy of cdev->gadget */
- struct fsg_common *common;
- u16 interface_number;
- unsigned int bulk_in_enabled:1;
- unsigned int bulk_out_enabled:1;
- unsigned long atomic_bitflags;
- #define IGNORE_BULK_OUT 0
- struct usb_ep *bulk_in;
- struct usb_ep *bulk_out;
- };
- static inline int __fsg_is_set(struct fsg_common *common,
- const char *func, unsigned line)
- {
- if (common->fsg)
- return 1;
- ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
- WARN_ON(1);
- return 0;
- }
- #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
- static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
- {
- return container_of(f, struct fsg_dev, function);
- }
- typedef void (*fsg_routine_t)(struct fsg_dev *);
- static int exception_in_progress(struct fsg_common *common)
- {
- return common->state > FSG_STATE_IDLE;
- }
- /* Make bulk-out requests be divisible by the maxpacket size */
- static void set_bulk_out_req_length(struct fsg_common *common,
- struct fsg_buffhd *bh, unsigned int length)
- {
- unsigned int rem;
- bh->bulk_out_intended_length = length;
- rem = length % common->bulk_out_maxpacket;
- if (rem > 0)
- length += common->bulk_out_maxpacket - rem;
- bh->outreq->length = length;
- }
- /*-------------------------------------------------------------------------*/
- static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
- {
- const char *name;
- if (ep == fsg->bulk_in)
- name = "bulk-in";
- else if (ep == fsg->bulk_out)
- name = "bulk-out";
- else
- name = ep->name;
- DBG(fsg, "%s set halt\n", name);
- return usb_ep_set_halt(ep);
- }
- /*-------------------------------------------------------------------------*/
- /* These routines may be called in process context or in_irq */
- /* Caller must hold fsg->lock */
- static void wakeup_thread(struct fsg_common *common)
- {
- /* Tell the main thread that something has happened */
- common->thread_wakeup_needed = 1;
- if (common->thread_task)
- wake_up_process(common->thread_task);
- }
- static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
- {
- unsigned long flags;
- /*
- * Do nothing if a higher-priority exception is already in progress.
- * If a lower-or-equal priority exception is in progress, preempt it
- * and notify the main thread by sending it a signal.
- */
- spin_lock_irqsave(&common->lock, flags);
- if (common->state <= new_state) {
- common->exception_req_tag = common->ep0_req_tag;
- common->state = new_state;
- if (common->thread_task)
- send_sig_info(SIGUSR1, SEND_SIG_FORCED,
- common->thread_task);
- }
- spin_unlock_irqrestore(&common->lock, flags);
- }
- /*-------------------------------------------------------------------------*/
- static int ep0_queue(struct fsg_common *common)
- {
- int rc;
- rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
- common->ep0->driver_data = common;
- if (rc != 0 && rc != -ESHUTDOWN) {
- /* We can't do much more than wait for a reset */
- WARNING(common, "error in submission: %s --> %d\n",
- common->ep0->name, rc);
- }
- return rc;
- }
- /*-------------------------------------------------------------------------*/
- /* Completion handlers. These always run in_irq. */
- static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
- {
- struct fsg_common *common = ep->driver_data;
- struct fsg_buffhd *bh = req->context;
- if (req->status || req->actual != req->length)
- DBG(common, "%s --> %d, %u/%u\n", __func__,
- req->status, req->actual, req->length);
- if (req->status == -ECONNRESET) /* Request was cancelled */
- usb_ep_fifo_flush(ep);
- /* Hold the lock while we update the request and buffer states */
- smp_wmb();
- spin_lock(&common->lock);
- bh->inreq_busy = 0;
- bh->state = BUF_STATE_EMPTY;
- wakeup_thread(common);
- spin_unlock(&common->lock);
- }
- static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
- {
- struct fsg_common *common = ep->driver_data;
- struct fsg_buffhd *bh = req->context;
- dump_msg(common, "bulk-out", req->buf, req->actual);
- if (req->status || req->actual != bh->bulk_out_intended_length)
- DBG(common, "%s --> %d, %u/%u\n", __func__,
- req->status, req->actual, bh->bulk_out_intended_length);
- if (req->status == -ECONNRESET) /* Request was cancelled */
- usb_ep_fifo_flush(ep);
- /* Hold the lock while we update the request and buffer states */
- smp_wmb();
- spin_lock(&common->lock);
- bh->outreq_busy = 0;
- bh->state = BUF_STATE_FULL;
- wakeup_thread(common);
- spin_unlock(&common->lock);
- }
- static int fsg_setup(struct usb_function *f,
- const struct usb_ctrlrequest *ctrl)
- {
- struct fsg_dev *fsg = fsg_from_func(f);
- struct usb_request *req = fsg->common->ep0req;
- u16 w_index = le16_to_cpu(ctrl->wIndex);
- u16 w_value = le16_to_cpu(ctrl->wValue);
- u16 w_length = le16_to_cpu(ctrl->wLength);
- if (!fsg_is_set(fsg->common))
- return -EOPNOTSUPP;
- ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
- req->context = NULL;
- req->length = 0;
- dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
- switch (ctrl->bRequest) {
- case USB_BULK_RESET_REQUEST:
- if (ctrl->bRequestType !=
- (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
- break;
- if (w_index != fsg->interface_number || w_value != 0)
- return -EDOM;
- /*
- * Raise an exception to stop the current operation
- * and reinitialize our state.
- */
- DBG(fsg, "bulk reset request\n");
- raise_exception(fsg->common, FSG_STATE_RESET);
- return DELAYED_STATUS;
- case USB_BULK_GET_MAX_LUN_REQUEST:
- if (ctrl->bRequestType !=
- (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
- break;
- if (w_index != fsg->interface_number || w_value != 0)
- return -EDOM;
- VDBG(fsg, "get max LUN\n");
- *(u8 *)req->buf = fsg->common->nluns - 1;
- /* Respond with data/status */
- req->length = min((u16)1, w_length);
- return ep0_queue(fsg->common);
- }
- VDBG(fsg,
- "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
- ctrl->bRequestType, ctrl->bRequest,
- le16_to_cpu(ctrl->wValue), w_index, w_length);
- return -EOPNOTSUPP;
- }
- /*-------------------------------------------------------------------------*/
- /* All the following routines run in process context */
- /* Use this for bulk or interrupt transfers, not ep0 */
- static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
- struct usb_request *req, int *pbusy,
- enum fsg_buffer_state *state)
- {
- int rc;
- if (ep == fsg->bulk_in)
- dump_msg(fsg, "bulk-in", req->buf, req->length);
- spin_lock_irq(&fsg->common->lock);
- *pbusy = 1;
- *state = BUF_STATE_BUSY;
- spin_unlock_irq(&fsg->common->lock);
- rc = usb_ep_queue(ep, req, GFP_KERNEL);
- if (rc != 0) {
- *pbusy = 0;
- *state = BUF_STATE_EMPTY;
- /* We can't do much more than wait for a reset */
- /*
- * Note: currently the net2280 driver fails zero-length
- * submissions if DMA is enabled.
- */
- if (rc != -ESHUTDOWN &&
- !(rc == -EOPNOTSUPP && req->length == 0))
- WARNING(fsg, "error in submission: %s --> %d\n",
- ep->name, rc);
- }
- }
- static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
- {
- if (!fsg_is_set(common))
- return false;
- start_transfer(common->fsg, common->fsg->bulk_in,
- bh->inreq, &bh->inreq_busy, &bh->state);
- return true;
- }
- static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
- {
- if (!fsg_is_set(common))
- return false;
- start_transfer(common->fsg, common->fsg->bulk_out,
- bh->outreq, &bh->outreq_busy, &bh->state);
- return true;
- }
- static int sleep_thread(struct fsg_common *common)
- {
- int rc = 0;
- /* Wait until a signal arrives or we are woken up */
- for (;;) {
- try_to_freeze();
- set_current_state(TASK_INTERRUPTIBLE);
- if (signal_pending(current)) {
- rc = -EINTR;
- break;
- }
- if (common->thread_wakeup_needed)
- break;
- schedule();
- }
- __set_current_state(TASK_RUNNING);
- common->thread_wakeup_needed = 0;
- return rc;
- }
- /*-------------------------------------------------------------------------*/
- static int do_read(struct fsg_common *common)
- {
- struct fsg_lun *curlun = common->curlun;
- u32 lba;
- struct fsg_buffhd *bh;
- int rc;
- u32 amount_left;
- loff_t file_offset, file_offset_tmp;
- unsigned int amount;
- unsigned int partial_page;
- ssize_t nread;
- /*
- * Get the starting Logical Block Address and check that it's
- * not too big.
- */
- if (common->cmnd[0] == READ_6)
- lba = get_unaligned_be24(&common->cmnd[1]);
- else {
- lba = get_unaligned_be32(&common->cmnd[2]);
- /*
- * We allow DPO (Disable Page Out = don't save data in the
- * cache) and FUA (Force Unit Access = don't read from the
- * cache), but we don't implement them.
- */
- if ((common->cmnd[1] & ~0x18) != 0) {
- curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
- return -EINVAL;
- }
- }
- if (lba >= curlun->num_sectors) {
- curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
- return -EINVAL;
- }
- file_offset = ((loff_t) lba) << 9;
- /* Carry out the file reads */
- amount_left = common->data_size_from_cmnd;
- if (unlikely(amount_left == 0))
- return -EIO; /* No default reply */
- for (;;) {
- /*
- * Figure out how much we need to read:
- * Try to read the remaining amount.
- * But don't read more than the buffer size.
- * And don't try to read past the end of the file.
- * Finally, if we're not at a page boundary, don't read past
- * the next page.
- * If this means reading 0 then we were asked to read past
- * the end of file.
- */
- amount = min(amount_left, FSG_BUFLEN);
- amount = min((loff_t)amount,
- curlun->file_length - file_offset);
- partial_page = file_offset & (PAGE_CACHE_SIZE - 1);
- if (partial_page > 0)
- amount = min(amount, (unsigned int)PAGE_CACHE_SIZE -
- partial_page);
- /* Wait for the next buffer to become available */
- bh = common->next_buffhd_to_fill;
- while (bh->state != BUF_STATE_EMPTY) {
- rc = sleep_thread(common);
- if (rc)
- return rc;
- }
- /*
- * If we were asked to read past the end of file,
- * end with an empty buffer.
- */
- if (amount == 0) {
- curlun->sense_data =
- SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
- curlun->sense_data_info = file_offset >> 9;
- curlun->info_valid = 1;
- bh->inreq->length = 0;
- bh->state = BUF_STATE_FULL;
- break;
- }
- /* Perform the read */
- file_offset_tmp = file_offset;
- nread = vfs_read(curlun->filp,
- (char __user *)bh->buf,
- amount, &file_offset_tmp);
- VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
- (unsigned long long)file_offset, (int)nread);
- if (signal_pending(current))
- return -EINTR;
- if (nread < 0) {
- LDBG(curlun, "error in file read: %d\n", (int)nread);
- nread = 0;
- } else if (nread < amount) {
- LDBG(curlun, "partial file read: %d/%u\n",
- (int)nread, amount);
- nread -= (nread & 511); /* Round down to a block */
- }
- file_offset += nread;
- amount_left -= nread;
- common->residue -= nread;
- bh->inreq->length = nread;
- bh->state = BUF_STATE_FULL;
- /* If an error occurred, report it and its position */
- if (nread < amount) {
- curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
- curlun->sense_data_info = file_offset >> 9;
- curlun->info_valid = 1;
- break;
- }
- if (amount_left == 0)
- break; /* No more left to read */
- /* Send this buffer and go read some more */
- bh->inreq->zero = 0;
- if (!start_in_transfer(common, bh))
- /* Don't know what to do if common->fsg is NULL */
- return -EIO;
- common->next_buffhd_to_fill = bh->next;
- }
- return -EIO; /* No default reply */
- }
- /*-------------------------------------------------------------------------*/
- static int do_write(struct fsg_common *common)
- {
- struct fsg_lun *curlun = common->curlun;
- u32 lba;
- struct fsg_buffhd *bh;
- int get_some_more;
- u32 amount_left_to_req, amount_left_to_write;
- loff_t usb_offset, file_offset, file_offset_tmp;
- unsigned int amount;
- unsigned int partial_page;
- ssize_t nwritten;
- int rc;
- if (curlun->ro) {
- curlun->sense_data = SS_WRITE_PROTECTED;
- return -EINVAL;
- }
- spin_lock(&curlun->filp->f_lock);
- curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
- spin_unlock(&curlun->filp->f_lock);
- /*
- * Get the starting Logical Block Address and check that it's
- * not too big
- */
- if (common->cmnd[0] == WRITE_6)
- lba = get_unaligned_be24(&common->cmnd[1]);
- else {
- lba = get_unaligned_be32(&common->cmnd[2]);
- /*
- * We allow DPO (Disable Page Out = don't save data in the
- * cache) and FUA (Force Unit Access = write directly to the
- * medium). We don't implement DPO; we implement FUA by
- * performing synchronous output.
- */
- if (common->cmnd[1] & ~0x18) {
- curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
- return -EINVAL;
- }
- if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
- spin_lock(&curlun->filp->f_lock);
- curlun->filp->f_flags |= O_SYNC;
- spin_unlock(&curlun->filp->f_lock);
- }
- }
- if (lba >= curlun->num_sectors) {
- curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
- return -EINVAL;
- }
- /* Carry out the file writes */
- get_some_more = 1;
- file_offset = usb_offset = ((loff_t) lba) << 9;
- amount_left_to_req = common->data_size_from_cmnd;
- amount_left_to_write = common->data_size_from_cmnd;
- while (amount_left_to_write > 0) {
- /* Queue a request for more data from the host */
- bh = common->next_buffhd_to_fill;
- if (bh->state == BUF_STATE_EMPTY && get_some_more) {
- /*
- * Figure out how much we want to get:
- * Try to get the remaining amount.
- * But don't get more than the buffer size.
- * And don't try to go past the end of the file.
- * If we're not at a page boundary,
- * don't go past the next page.
- * If this means getting 0, then we were asked
- * to write past the end of file.
- * Finally, round down to a block boundary.
- */
- amount = min(amount_left_to_req, FSG_BUFLEN);
- amount = min((loff_t)amount,
- curlun->file_length - usb_offset);
- partial_page = usb_offset & (PAGE_CACHE_SIZE - 1);
- if (partial_page > 0)
- amount = min(amount,
- (unsigned int)PAGE_CACHE_SIZE - partial_page);
- if (amount == 0) {
- get_some_more = 0;
- curlun->sense_data =
- SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
- curlun->sense_data_info = usb_offset >> 9;
- curlun->info_valid = 1;
- continue;
- }
- amount -= amount & 511;
- if (amount == 0) {
- /*
- * Why were we were asked to transfer a
- * partial block?
- */
- get_some_more = 0;
- continue;
- }
- /* Get the next buffer */
- usb_offset += amount;
- common->usb_amount_left -= amount;
- amount_left_to_req -= amount;
- if (amount_left_to_req == 0)
- get_some_more = 0;
- /*
- * amount is always divisible by 512, hence by
- * the bulk-out maxpacket size
- */
- bh->outreq->length = amount;
- bh->bulk_out_intended_length = amount;
- bh->outreq->short_not_ok = 1;
- if (!start_out_transfer(common, bh))
- /* Dunno what to do if common->fsg is NULL */
- return -EIO;
- common->next_buffhd_to_fill = bh->next;
- continue;
- }
- /* Write the received data to the backing file */
- bh = common->next_buffhd_to_drain;
- if (bh->state == BUF_STATE_EMPTY && !get_some_more)
- break; /* We stopped early */
- if (bh->state == BUF_STATE_FULL) {
- smp_rmb();
- common->next_buffhd_to_drain = bh->next;
- bh->state = BUF_STATE_EMPTY;
- /* Did something go wrong with the transfer? */
- if (bh->outreq->status != 0) {
- curlun->sense_data = SS_COMMUNICATION_FAILURE;
- curlun->sense_data_info = file_offset >> 9;
- curlun->info_valid = 1;
- break;
- }
- amount = bh->outreq->actual;
- if (curlun->file_length - file_offset < amount) {
- LERROR(curlun,
- "write %u @ %llu beyond end %llu\n",
- amount, (unsigned long long)file_offset,
- (unsigned long long)curlun->file_length);
- amount = curlun->file_length - file_offset;
- }
- /* Perform the write */
- file_offset_tmp = file_offset;
- nwritten = vfs_write(curlun->filp,
- (char __user *)bh->buf,
- amount, &file_offset_tmp);
- VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
- (unsigned long long)file_offset, (int)nwritten);
- if (signal_pending(current))
- return -EINTR; /* Interrupted! */
- if (nwritten < 0) {
- LDBG(curlun, "error in file write: %d\n",
- (int)nwritten);
- nwritten = 0;
- } else if (nwritten < amount) {
- LDBG(curlun, "partial file write: %d/%u\n",
- (int)nwritten, amount);
- nwritten -= (nwritten & 511);
- /* Round down to a block */
- }
- file_offset += nwritten;
- amount_left_to_write -= nwritten;
- common->residue -= nwritten;
- /* If an error occurred, report it and its position */
- if (nwritten < amount) {
- curlun->sense_data = SS_WRITE_ERROR;
- curlun->sense_data_info = file_offset >> 9;
- curlun->info_valid = 1;
- break;
- }
- /* Did the host decide to stop early? */
- if (bh->outreq->actual != bh->outreq->length) {
- common->short_packet_received = 1;
- break;
- }
- continue;
- }
- /* Wait for something to happen */
- rc = sleep_thread(common);
- if (rc)
- return rc;
- }
- return -EIO; /* No default reply */
- }
- /*-------------------------------------------------------------------------*/
- static int do_synchronize_cache(struct fsg_common *common)
- {
- struct fsg_lun *curlun = common->curlun;
- int rc;
- /* We ignore the requested LBA and write out all file's
- * dirty data buffers. */
- rc = fsg_lun_fsync_sub(curlun);
- if (rc)
- curlun->sense_data = SS_WRITE_ERROR;
- return 0;
- }
- /*-------------------------------------------------------------------------*/
- static void invalidate_sub(struct fsg_lun *curlun)
- {
- struct file *filp = curlun->filp;
- struct inode *inode = filp->f_path.dentry->d_inode;
- unsigned long rc;
- rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
- VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
- }
- static int do_verify(struct fsg_common *common)
- {
- struct fsg_lun *curlun = common->curlun;
- u32 lba;
- u32 verification_length;
- struct fsg_buffhd *bh = common->next_buffhd_to_fill;
- loff_t file_offset, file_offset_tmp;
- u32 amount_left;
- unsigned int amount;
- ssize_t nread;
- /*
- * Get the starting Logical Block Address and check that it's
- * not too big.
- */
- lba = get_unaligned_be32(&common->cmnd[2]);
- if (lba >= curlun->num_sectors) {
- curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
- return -EINVAL;
- }
- /*
- * We allow DPO (Disable Page Out = don't save data in the
- * cache) but we don't implement it.
- */
- if (common->cmnd[1] & ~0x10) {
- curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
- return -EINVAL;
- }
- verification_length = get_unaligned_be16(&common->cmnd[7]);
- if (unlikely(verification_length == 0))
- return -EIO; /* No default reply */
- /* Prepare to carry out the file verify */
- amount_left = verification_length << 9;
- file_offset = ((loff_t) lba) << 9;
- /* Write out all the dirty buffers before invalidating them */
- fsg_lun_fsync_sub(curlun);
- if (signal_pending(current))
- return -EINTR;
- invalidate_sub(curlun);
- if (signal_pending(current))
- return -EINTR;
- /* Just try to read the requested blocks */
- while (amount_left > 0) {
- /*
- * Figure out how much we need to read:
- * Try to read the remaining amount, but not more than
- * the buffer size.
- * And don't try to read past the end of the file.
- * If this means reading 0 then we were asked to read
- * past the end of file.
- */
- amount = min(amount_left, FSG_BUFLEN);
- amount = min((loff_t)amount,
- curlun->file_length - file_offset);
- if (amount == 0) {
- curlun->sense_data =
- SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
- curlun->sense_data_info = file_offset >> 9;
- curlun->info_valid = 1;
- break;
- }
- /* Perform the read */
- file_offset_tmp = file_offset;
- nread = vfs_read(curlun->filp,
- (char __user *) bh->buf,
- amount, &file_offset_tmp);
- VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
- (unsigned long long) file_offset,
- (int) nread);
- if (signal_pending(current))
- return -EINTR;
- if (nread < 0) {
- LDBG(curlun, "error in file verify: %d\n", (int)nread);
- nread = 0;
- } else if (nread < amount) {
- LDBG(curlun, "partial file verify: %d/%u\n",
- (int)nread, amount);
- nread -= nread & 511; /* Round down to a sector */
- }
- if (nread == 0) {
- curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
- curlun->sense_data_info = file_offset >> 9;
- curlun->info_valid = 1;
- break;
- }
- file_offset += nread;
- amount_left -= nread;
- }
- return 0;
- }
- /*-------------------------------------------------------------------------*/
- static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
- {
- struct fsg_lun *curlun = common->curlun;
- u8 *buf = (u8 *) bh->buf;
- if (!curlun) { /* Unsupported LUNs are okay */
- common->bad_lun_okay = 1;
- memset(buf, 0, 36);
- buf[0] = 0x7f; /* Unsupported, no device-type */
- buf[4] = 31; /* Additional length */
- return 36;
- }
- buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
- buf[1] = curlun->removable ? 0x80 : 0;
- buf[2] = 2; /* ANSI SCSI level 2 */
- buf[3] = 2; /* SCSI-2 INQUIRY data format */
- buf[4] = 31; /* Additional length */
- buf[5] = 0; /* No special options */
- buf[6] = 0;
- buf[7] = 0;
- memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
- return 36;
- }
- static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
- {
- struct fsg_lun *curlun = common->curlun;
- u8 *buf = (u8 *) bh->buf;
- u32 sd, sdinfo;
- int valid;
- /*
- * From the SCSI-2 spec., section 7.9 (Unit attention condition):
- *
- * If a REQUEST SENSE command is received from an initiator
- * with a pending unit attention condition (before the target
- * generates the contingent allegiance condition), then the
- * target shall either:
- * a) report any pending sense data and preserve the unit
- * attention condition on the logical unit, or,
- * b) report the unit attention condition, may discard any
- * pending sense data, and clear the unit attention
- * condition on the logical unit for that initiator.
- *
- * FSG normally uses option a); enable this code to use option b).
- */
- #if 0
- if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
- curlun->sense_data = curlun->unit_attention_data;
- curlun->unit_attention_data = SS_NO_SENSE;
- }
- #endif
- if (!curlun) { /* Unsupported LUNs are okay */
- common->bad_lun_okay = 1;
- sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
- sdinfo = 0;
- valid = 0;
- } else {
- sd = curlun->sense_data;
- sdinfo = curlun->sense_data_info;
- valid = curlun->info_valid << 7;
- curlun->sense_data = SS_NO_SENSE;
- curlun->sense_data_info = 0;
- curlun->info_valid = 0;
- }
- memset(buf, 0, 18);
- buf[0] = valid | 0x70; /* Valid, current error */
- buf[2] = SK(sd);
- put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
- buf[7] = 18 - 8; /* Additional sense length */
- buf[12] = ASC(sd);
- buf[13] = ASCQ(sd);
- return 18;
- }
- static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
- {
- struct fsg_lun *curlun = common->curlun;
- u32 lba = get_unaligned_be32(&common->cmnd[2]);
- int pmi = common->cmnd[8];
- u8 *buf = (u8 *)bh->buf;
- /* Check the PMI and LBA fields */
- if (pmi > 1 || (pmi == 0 && lba != 0)) {
- curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
- return -EINVAL;
- }
- put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
- /* Max logical block */
- put_unaligned_be32(512, &buf[4]); /* Block length */
- return 8;
- }
- static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
- {
- struct fsg_lun *curlun = common->curlun;
- int msf = common->cmnd[1] & 0x02;
- u32 lba = get_unaligned_be32(&common->cmnd[2]);
- u8 *buf = (u8 *)bh->buf;
- if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
- curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
- return -EINVAL;
- }
- if (lba >= curlun->num_sectors) {
- curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
- return -EINVAL;
- }
- memset(buf, 0, 8);
- buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
- store_cdrom_address(&buf[4], msf, lba);
- return 8;
- }
- static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
- {
- struct fsg_lun *curlun = common->curlun;
- int msf = common->cmnd[1] & 0x02;
- int start_track = common->cmnd[6];
- u8 *buf = (u8 *)bh->buf;
- if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
- start_track > 1) {
- curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
- return -EINVAL;
- }
- memset(buf, 0, 20);
- buf[1] = (20-2); /* TOC data length */
- buf[2] = 1; /* First track number */
- buf[3] = 1; /* Last track number */
- buf[5] = 0x16; /* Data track, copying allowed */
- buf[6] = 0x01; /* Only track is number 1 */
- store_cdrom_address(&buf[8], msf, 0);
- buf[13] = 0x16; /* Lead-out track is data */
- buf[14] = 0xAA; /* Lead-out track number */
- store_cdrom_address(&buf[16], msf, curlun->num_sectors);
- return 20;
- }
- static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
- {
- struct fsg_lun *curlun = common->curlun;
- int mscmnd = common->cmnd[0];
- u8 *buf = (u8 *) bh->buf;
- u8 *buf0 = buf;
- int pc, page_code;
- int changeable_values, all_pages;
- int valid_page = 0;
- int len, limit;
- if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
- curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
- return -EINVAL;
- }
- pc = common->cmnd[2] >> 6;
- page_code = common->cmnd[2] & 0x3f;
- if (pc == 3) {
- curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
- return -EINVAL;
- }
- changeable_values = (pc == 1);
- all_pages = (page_code == 0x3f);
- /*
- * Write the mode parameter header. Fixed values are: default
- * medium type, no cache control (DPOFUA), and no block descriptors.
- * The only variable value is the WriteProtect bit. We will fill in
- * the mode data length later.
- */
- memset(buf, 0, 8);
- if (mscmnd == MODE_SENSE) {
- buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
- buf += 4;
- limit = 255;
- } else { /* MODE_SENSE_10 */
- buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
- buf += 8;
- limit = 65535; /* Should really be FSG_BUFLEN */
- }
- /* No block descriptors */
- /*
- * The mode pages, in numerical order. The only page we support
- * is the Caching page.
- */
- if (page_code == 0x08 || all_pages) {
- valid_page = 1;
- buf[0] = 0x08; /* Page code */
- buf[1] = 10; /* Page length */
- memset(buf+2, 0, 10); /* None of the fields are changeable */
- if (!changeable_values) {
- buf[2] = 0x04; /* Write cache enable, */
- /* Read cache not disabled */
- /* No cache retention priorities */
- put_unaligned_be16(0xffff, &buf[4]);
- /* Don't disable prefetch */
- /* Minimum prefetch = 0 */
- put_unaligned_be16(0xffff, &buf[8]);
- /* Maximum prefetch */
- put_unaligned_be16(0xffff, &buf[10]);
- /* Maximum prefetch ceiling */
- }
- buf += 12;
- }
- /*
- * Check that a valid page was requested and the mode data length
- * isn't too long.
- */
- len = buf - buf0;
- if (!valid_page || len > limit) {
- curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
- return -EINVAL;
- }
- /* Store the mode data length */
- if (mscmnd == MODE_SENSE)
- buf0[0] = len - 1;
- else
- put_unaligned_be16(len - 2, buf0);
- return len;
- }
- static int do_start_stop(struct fsg_common *common)
- {
- struct fsg_lun *curlun = common->curlun;
- int loej, start;
- if (!curlun) {
- return -EINVAL;
- } else if (!curlun->removable) {
- curlun->sense_data = SS_INVALID_COMMAND;
- return -EINVAL;
- } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
- (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
- curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
- return -EINVAL;
- }
- loej = common->cmnd[4] & 0x02;
- start = common->cmnd[4] & 0x01;
- /*
- * Our emulation doesn't support mounting; the medium is
- * available for use as soon as it is loaded.
- */
- if (start) {
- if (!fsg_lun_is_open(curlun)) {
- curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
- return -EINVAL;
- }
- return 0;
- }
- /* Are we allowed to unload the media? */
- if (curlun->prevent_medium_removal) {
- LDBG(curlun, "unload attempt prevented\n");
- curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
- return -EINVAL;
- }
- if (!loej)
- return 0;
- /* Simulate an unload/eject */
- if (common->ops && common->ops->pre_eject) {
- int r = common->ops->pre_eject(common, curlun,
- curlun - common->luns);
- if (unlikely(r < 0))
- return r;
- else if (r)
- return 0;
- }
- up_read(&common->filesem);
- down_write(&common->filesem);
- fsg_lun_close(curlun);
- up_write(&common->filesem);
- down_read(&common->filesem);
- return common->ops && common->ops->post_eject
- ? min(0, common->ops->post_eject(common, curlun,
- curlun - common->luns))
- : 0;
- }
- static int do_prevent_allow(struct fsg_common *common)
- {
- struct fsg_lun *curlun = common->curlun;
- int prevent;
- if (!common->curlun) {
- return -EINVAL;
- } else if (!common->curlun->removable) {
- common->curlun->sense_data = SS_INVALID_COMMAND;
- return -EINVAL;
- }
- prevent = common->cmnd[4] & 0x01;
- if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
- curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
- return -EINVAL;
- }
- if (curlun->prevent_medium_removal && !prevent)
- fsg_lun_fsync_sub(curlun);
- curlun->prevent_medium_removal = prevent;
- return 0;
- }
- static int do_read_format_capacities(struct fsg_common *common,
- struct fsg_buffhd *bh)
- {
- struct fsg_lun *curlun = common->curlun;
- u8 *buf = (u8 *) bh->buf;
- buf[0] = buf[1] = buf[2] = 0;
- buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
- buf += 4;
- put_unaligned_be32(curlun->num_sectors, &buf[0]);
- /* Number of blocks */
- put_unaligned_be32(512, &buf[4]); /* Block length */
- buf[4] = 0x02; /* Current capacity */
- return 12;
- }
- static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
- {
- struct fsg_lun *curlun = common->curlun;
- /* We don't support MODE SELECT */
- if (curlun)
- curlun->sense_data = SS_INVALID_COMMAND;
- return -EINVAL;
- }
- /*-------------------------------------------------------------------------*/
- static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
- {
- int rc;
- rc = fsg_set_halt(fsg, fsg->bulk_in);
- if (rc == -EAGAIN)
- VDBG(fsg, "delayed bulk-in endpoint halt\n");
- while (rc != 0) {
- if (rc != -EAGAIN) {
- WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
- rc = 0;
- break;
- }
- /* Wait for a short time and then try again */
- if (msleep_interruptible(100) != 0)
- return -EINTR;
- rc = usb_ep_set_halt(fsg->bulk_in);
- }
- return rc;
- }
- static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
- {
- int rc;
- DBG(fsg, "bulk-in set wedge\n");
- rc = usb_ep_set_wedge(fsg->bulk_in);
- if (rc == -EAGAIN)
- VDBG(fsg, "delayed bulk-in endpoint wedge\n");
- while (rc != 0) {
- if (rc != -EAGAIN) {
- WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
- rc = 0;
- break;
- }
- /* Wait for a short time and then try again */
- if (msleep_interruptible(100) != 0)
- return -EINTR;
- rc = usb_ep_set_wedge(fsg->bulk_in);
- }
- return rc;
- }
- static int throw_away_data(struct fsg_common *common)
- {
- struct fsg_buffhd *bh;
- u32 amount;
- int rc;
- for (bh = common->next_buffhd_to_drain;
- bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
- bh = common->next_buffhd_to_drain) {
- /* Throw away the data in a filled buffer */
- if (bh->state == BUF_STATE_FULL) {
- smp_rmb();
- bh->state = BUF_STATE_EMPTY;
- common->next_buffhd_to_drain = bh->next;
- /* A short packet or an error ends everything */
- if (bh->outreq->actual != bh->outreq->length ||
- bh->outreq->status != 0) {
- raise_exception(common,
- FSG_STATE_ABORT_BULK_OUT);
- return -EINTR;
- }
- continue;
- }
- /* Try to submit another request if we need one */
- bh = common->next_buffhd_to_fill;
- if (bh->state == BUF_STATE_EMPTY
- && common->usb_amount_left > 0) {
- amount = min(common->usb_amount_left, FSG_BUFLEN);
- /*
- * amount is always divisible by 512, hence by
- * the bulk-out maxpacket size.
- */
- bh->outreq->length = amount;
- bh->bulk_out_intended_length = amount;
- bh->outreq->short_not_ok = 1;
- if (!start_out_transfer(common, bh))
- /* Dunno what to do if common->fsg is NULL */
- return -EIO;
- common->next_buffhd_to_fill = bh->next;
- common->usb_amount_left -= amount;
- continue;
- }
- /* Otherwise wait for something to happen */
- rc = sleep_thread(common);
- if (rc)
- return rc;
- }
- return 0;
- }
- static int finish_reply(struct fsg_common *common)
- {
- struct fsg_buffhd *bh = common->next_buffhd_to_fill;
- int rc = 0;
- switch (common->data_dir) {
- case DATA_DIR_NONE:
- break; /* Nothing to send */
- /*
- * If we don't know whether the host wants to read or write,
- * this must be CB or CBI with an unknown command. We