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linux/drivers/usb/gadget/file_storage.c
Alan Stern 82a10a81c8 USB: g_file_storage: fix use-after-free bug when closing files 
This patch (as1231) fixes a use-after-free bug in g_file_storage.  A
device's name may not be available after the device is unregistered,
even if the device structure itself is still allocated.  Since
close_backing_file() prints a LUN's name for debugging, it shouldn't
be called after the LUN has been unregistered.

That whole area needed to be cleaned up; the backing files were
getting closed in a couple of different places.  The patch fixes
things so that they get closed in just one place, as part of the
unbind procedure, immediately before the LUN is unregistered.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-23 14:15:28 -07:00

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/*
* file_storage.c -- File-backed USB Storage Gadget, for USB development
*
* Copyright (C) 2003-2008 Alan Stern
* 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 File-backed Storage Gadget 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 gadget driver for a USB
* device, it also illustrates a technique of double-buffering for increased
* throughput. Last but not least, it gives an easy way to probe the
* behavior of the Mass Storage drivers in a USB host.
*
* Backing storage is provided by a regular file or a block device, specified
* by the "file" module parameter. Access can be limited to read-only by
* setting the optional "ro" module parameter. (For CD-ROM emulation,
* access is always read-only.) The gadget will indicate that it has
* removable media if the optional "removable" module parameter is set.
*
* The gadget supports the Control-Bulk (CB), Control-Bulk-Interrupt (CBI),
* and Bulk-Only (also known as Bulk-Bulk-Bulk or BBB) transports, selected
* by the optional "transport" module parameter. It also supports the
* following protocols: RBC (0x01), ATAPI or SFF-8020i (0x02), QIC-157 (0c03),
* UFI (0x04), SFF-8070i (0x05), and transparent SCSI (0x06), selected by
* the optional "protocol" module parameter. In addition, the default
* Vendor ID, Product ID, and release number can be overridden.
*
* There is support for multiple logical units (LUNs), each of which has
* its own backing file. The number of LUNs can be set using the optional
* "luns" module parameter (anywhere from 1 to 8), and the corresponding
* files are specified using comma-separated lists for "file" and "ro".
* The default number of LUNs is taken from the number of "file" elements;
* it is 1 if "file" is not given. If "removable" is not set then a backing
* file must be specified for each LUN. If it is set, then an unspecified
* or empty backing filename means the LUN's medium is not loaded. Ideally
* each LUN would be settable independently as a disk drive or a CD-ROM
* drive, but currently all LUNs have to be the same type. 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.
*
* Requirements are modest; only a bulk-in and a bulk-out endpoint are
* needed (an interrupt-out endpoint is also needed for CBI). 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.
*
* Module options:
*
* file=filename[,filename...]
* Required if "removable" is not set, names of
* the files or block devices used for
* backing storage
* ro=b[,b...] Default false, booleans for read-only access
* removable Default false, boolean for removable media
* 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
* cdrom Default false, boolean for whether to emulate
* a CD-ROM drive
* transport=XXX Default BBB, transport name (CB, CBI, or BBB)
* protocol=YYY Default SCSI, protocol name (RBC, 8020 or
* ATAPI, QIC, UFI, 8070, or SCSI;
* also 1 - 6)
* vendor=0xVVVV Default 0x0525 (NetChip), USB Vendor ID
* product=0xPPPP Default 0xa4a5 (FSG), USB Product ID
* release=0xRRRR Override the USB release number (bcdDevice)
* buflen=N Default N=16384, buffer size used (will be
* rounded down to a multiple of
* PAGE_CACHE_SIZE)
*
* If CONFIG_USB_FILE_STORAGE_TEST is not set, only the "file", "ro",
* "removable", "luns", "stall", and "cdrom" options are available; default
* values are used for everything else.
*
* The pathnames of the backing files and the ro settings are available in
* the attribute files "file" and "ro" in the lun<n> 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.
*
* This gadget driver 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 FSG driver 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. So just before the thread
* exits, it deregisters the gadget driver. This makes things a little
* tricky: The driver is deregistered at two places, and the exiting
* thread can indirectly call fsg_unbind() which in turn can tell the
* thread to exit. The first problem is resolved through the use of the
* REGISTERED atomic bitflag; the driver will only be deregistered once.
* The second problem is resolved by having fsg_unbind() check
* fsg->state; it won't try to stop the thread if the state is already
* FSG_STATE_TERMINATED.
*
* 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 "gadget_chips.h"
/*
* Kbuild is not very cooperative with respect to linking separately
* compiled library objects into one module. So for now we won't use
* separate compilation ... ensuring init/exit sections work to shrink
* the runtime footprint, and giving us at least some parts of what
* a "gcc --combine ... part1.c part2.c part3.c ... " build would.
*/
#include "usbstring.c"
#include "config.c"
#include "epautoconf.c"
/*-------------------------------------------------------------------------*/
#define DRIVER_DESC "File-backed Storage Gadget"
#define DRIVER_NAME "g_file_storage"
#define DRIVER_VERSION "20 November 2008"
static const char longname[] = DRIVER_DESC;
static const char shortname[] = DRIVER_NAME;
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Alan Stern");
MODULE_LICENSE("Dual BSD/GPL");
/* Thanks to NetChip Technologies for donating this product ID.
*
* DO NOT REUSE THESE IDs with any other driver!! Ever!!
* Instead: allocate your own, using normal USB-IF procedures. */
#define DRIVER_VENDOR_ID 0x0525 // NetChip
#define DRIVER_PRODUCT_ID 0xa4a5 // Linux-USB File-backed Storage Gadget
/*
* This driver assumes self-powered hardware and has no way for users to
* trigger remote wakeup. It uses autoconfiguration to select endpoints
* and endpoint addresses.
*/
/*-------------------------------------------------------------------------*/
#define LDBG(lun,fmt,args...) \
dev_dbg(&(lun)->dev , fmt , ## args)
#define MDBG(fmt,args...) \
pr_debug(DRIVER_NAME ": " fmt , ## args)
#ifndef DEBUG
#undef VERBOSE_DEBUG
#undef DUMP_MSGS
#endif /* !DEBUG */
#ifdef VERBOSE_DEBUG
#define VLDBG LDBG
#else
#define VLDBG(lun,fmt,args...) \
do { } while (0)
#endif /* VERBOSE_DEBUG */
#define LERROR(lun,fmt,args...) \
dev_err(&(lun)->dev , fmt , ## args)
#define LWARN(lun,fmt,args...) \
dev_warn(&(lun)->dev , fmt , ## args)
#define LINFO(lun,fmt,args...) \
dev_info(&(lun)->dev , fmt , ## args)
#define MINFO(fmt,args...) \
pr_info(DRIVER_NAME ": " fmt , ## args)
#define DBG(d, fmt, args...) \
dev_dbg(&(d)->gadget->dev , fmt , ## args)
#define VDBG(d, fmt, args...) \
dev_vdbg(&(d)->gadget->dev , fmt , ## args)
#define ERROR(d, fmt, args...) \
dev_err(&(d)->gadget->dev , fmt , ## args)
#define WARNING(d, fmt, args...) \
dev_warn(&(d)->gadget->dev , fmt , ## args)
#define INFO(d, fmt, args...) \
dev_info(&(d)->gadget->dev , fmt , ## args)
/*-------------------------------------------------------------------------*/
/* Encapsulate the module parameter settings */
#define MAX_LUNS 8
static struct {
char *file[MAX_LUNS];
int ro[MAX_LUNS];
unsigned int num_filenames;
unsigned int num_ros;
unsigned int nluns;
int removable;
int can_stall;
int cdrom;
char *transport_parm;
char *protocol_parm;
unsigned short vendor;
unsigned short product;
unsigned short release;
unsigned int buflen;
int transport_type;
char *transport_name;
int protocol_type;
char *protocol_name;
} mod_data = { // Default values
.transport_parm = "BBB",
.protocol_parm = "SCSI",
.removable = 0,
.can_stall = 1,
.cdrom = 0,
.vendor = DRIVER_VENDOR_ID,
.product = DRIVER_PRODUCT_ID,
.release = 0xffff, // Use controller chip type
.buflen = 16384,
};
module_param_array_named(file, mod_data.file, charp, &mod_data.num_filenames,
S_IRUGO);
MODULE_PARM_DESC(file, "names of backing files or devices");
module_param_array_named(ro, mod_data.ro, bool, &mod_data.num_ros, S_IRUGO);
MODULE_PARM_DESC(ro, "true to force read-only");
module_param_named(luns, mod_data.nluns, uint, S_IRUGO);
MODULE_PARM_DESC(luns, "number of LUNs");
module_param_named(removable, mod_data.removable, bool, S_IRUGO);
MODULE_PARM_DESC(removable, "true to simulate removable media");
module_param_named(stall, mod_data.can_stall, bool, S_IRUGO);
MODULE_PARM_DESC(stall, "false to prevent bulk stalls");
module_param_named(cdrom, mod_data.cdrom, bool, S_IRUGO);
MODULE_PARM_DESC(cdrom, "true to emulate cdrom instead of disk");
/* In the non-TEST version, only the module parameters listed above
* are available. */
#ifdef CONFIG_USB_FILE_STORAGE_TEST
module_param_named(transport, mod_data.transport_parm, charp, S_IRUGO);
MODULE_PARM_DESC(transport, "type of transport (BBB, CBI, or CB)");
module_param_named(protocol, mod_data.protocol_parm, charp, S_IRUGO);
MODULE_PARM_DESC(protocol, "type of protocol (RBC, 8020, QIC, UFI, "
"8070, or SCSI)");
module_param_named(vendor, mod_data.vendor, ushort, S_IRUGO);
MODULE_PARM_DESC(vendor, "USB Vendor ID");
module_param_named(product, mod_data.product, ushort, S_IRUGO);
MODULE_PARM_DESC(product, "USB Product ID");
module_param_named(release, mod_data.release, ushort, S_IRUGO);
MODULE_PARM_DESC(release, "USB release number");
module_param_named(buflen, mod_data.buflen, uint, S_IRUGO);
MODULE_PARM_DESC(buflen, "I/O buffer size");
#endif /* CONFIG_USB_FILE_STORAGE_TEST */
/*-------------------------------------------------------------------------*/
/* SCSI device types */
#define TYPE_DISK 0x00
#define TYPE_CDROM 0x05
/* USB protocol value = the transport method */
#define USB_PR_CBI 0x00 // Control/Bulk/Interrupt
#define USB_PR_CB 0x01 // Control/Bulk w/o interrupt
#define USB_PR_BULK 0x50 // Bulk-only
/* USB subclass value = the protocol encapsulation */
#define USB_SC_RBC 0x01 // Reduced Block Commands (flash)
#define USB_SC_8020 0x02 // SFF-8020i, MMC-2, ATAPI (CD-ROM)
#define USB_SC_QIC 0x03 // QIC-157 (tape)
#define USB_SC_UFI 0x04 // UFI (floppy)
#define USB_SC_8070 0x05 // SFF-8070i (removable)
#define USB_SC_SCSI 0x06 // Transparent SCSI
/* Bulk-only data structures */
/* Command Block Wrapper */
struct bulk_cb_wrap {
__le32 Signature; // Contains 'USBC'
u32 Tag; // Unique per command id
__le32 DataTransferLength; // Size of the data
u8 Flags; // Direction in bit 7
u8 Lun; // LUN (normally 0)
u8 Length; // Of the CDB, <= MAX_COMMAND_SIZE
u8 CDB[16]; // Command Data Block
};
#define USB_BULK_CB_WRAP_LEN 31
#define USB_BULK_CB_SIG 0x43425355 // Spells out USBC
#define USB_BULK_IN_FLAG 0x80
/* Command Status Wrapper */
struct bulk_cs_wrap {
__le32 Signature; // Should = 'USBS'
u32 Tag; // Same as original command
__le32 Residue; // Amount not transferred
u8 Status; // See below
};
#define USB_BULK_CS_WRAP_LEN 13
#define USB_BULK_CS_SIG 0x53425355 // Spells out 'USBS'
#define USB_STATUS_PASS 0
#define USB_STATUS_FAIL 1
#define USB_STATUS_PHASE_ERROR 2
/* Bulk-only class specific requests */
#define USB_BULK_RESET_REQUEST 0xff
#define USB_BULK_GET_MAX_LUN_REQUEST 0xfe
/* CBI Interrupt data structure */
struct interrupt_data {
u8 bType;
u8 bValue;
};
#define CBI_INTERRUPT_DATA_LEN 2
/* CBI Accept Device-Specific Command request */
#define USB_CBI_ADSC_REQUEST 0x00
#define MAX_COMMAND_SIZE 16 // Length of a SCSI Command Data Block
/* SCSI commands that we recognize */
#define SC_FORMAT_UNIT 0x04
#define SC_INQUIRY 0x12
#define SC_MODE_SELECT_6 0x15
#define SC_MODE_SELECT_10 0x55
#define SC_MODE_SENSE_6 0x1a
#define SC_MODE_SENSE_10 0x5a
#define SC_PREVENT_ALLOW_MEDIUM_REMOVAL 0x1e
#define SC_READ_6 0x08
#define SC_READ_10 0x28
#define SC_READ_12 0xa8
#define SC_READ_CAPACITY 0x25
#define SC_READ_FORMAT_CAPACITIES 0x23
#define SC_READ_HEADER 0x44
#define SC_READ_TOC 0x43
#define SC_RELEASE 0x17
#define SC_REQUEST_SENSE 0x03
#define SC_RESERVE 0x16
#define SC_SEND_DIAGNOSTIC 0x1d
#define SC_START_STOP_UNIT 0x1b
#define SC_SYNCHRONIZE_CACHE 0x35
#define SC_TEST_UNIT_READY 0x00
#define SC_VERIFY 0x2f
#define SC_WRITE_6 0x0a
#define SC_WRITE_10 0x2a
#define SC_WRITE_12 0xaa
/* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
#define SS_NO_SENSE 0
#define SS_COMMUNICATION_FAILURE 0x040800
#define SS_INVALID_COMMAND 0x052000
#define SS_INVALID_FIELD_IN_CDB 0x052400
#define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE 0x052100
#define SS_LOGICAL_UNIT_NOT_SUPPORTED 0x052500
#define SS_MEDIUM_NOT_PRESENT 0x023a00
#define SS_MEDIUM_REMOVAL_PREVENTED 0x055302
#define SS_NOT_READY_TO_READY_TRANSITION 0x062800
#define SS_RESET_OCCURRED 0x062900
#define SS_SAVING_PARAMETERS_NOT_SUPPORTED 0x053900
#define SS_UNRECOVERED_READ_ERROR 0x031100
#define SS_WRITE_ERROR 0x030c02
#define SS_WRITE_PROTECTED 0x072700
#define SK(x) ((u8) ((x) >> 16)) // Sense Key byte, etc.
#define ASC(x) ((u8) ((x) >> 8))
#define ASCQ(x) ((u8) (x))
/*-------------------------------------------------------------------------*/
/*
* These definitions will permit the compiler to avoid generating code for
* parts of the driver that aren't used in the non-TEST version. Even gcc
* can recognize when a test of a constant expression yields a dead code
* path.
*/
#ifdef CONFIG_USB_FILE_STORAGE_TEST
#define transport_is_bbb() (mod_data.transport_type == USB_PR_BULK)
#define transport_is_cbi() (mod_data.transport_type == USB_PR_CBI)
#define protocol_is_scsi() (mod_data.protocol_type == USB_SC_SCSI)
#else
#define transport_is_bbb() 1
#define transport_is_cbi() 0
#define protocol_is_scsi() 1
#endif /* CONFIG_USB_FILE_STORAGE_TEST */
struct lun {
struct file *filp;
loff_t file_length;
loff_t num_sectors;
unsigned int ro : 1;
unsigned int prevent_medium_removal : 1;
unsigned int registered : 1;
unsigned int info_valid : 1;
u32 sense_data;
u32 sense_data_info;
u32 unit_attention_data;
struct device dev;
};
#define backing_file_is_open(curlun) ((curlun)->filp != NULL)
static struct lun *dev_to_lun(struct device *dev)
{
return container_of(dev, struct lun, dev);
}
/* Big enough to hold our biggest descriptor */
#define EP0_BUFSIZE 256
#define DELAYED_STATUS (EP0_BUFSIZE + 999) // An impossibly large value
/* Number of buffers we will use. 2 is enough for double-buffering */
#define NUM_BUFFERS 2
enum fsg_buffer_state {
BUF_STATE_EMPTY = 0,
BUF_STATE_FULL,
BUF_STATE_BUSY
};
struct fsg_buffhd {
void *buf;
enum fsg_buffer_state state;
struct fsg_buffhd *next;
/* The NetChip 2280 is faster, and handles some protocol faults
* better, if we don't submit any short bulk-out read requests.
* So we will record the intended request length here. */
unsigned int bulk_out_intended_length;
struct usb_request *inreq;
int inreq_busy;
struct usb_request *outreq;
int outreq_busy;
};
enum fsg_state {
FSG_STATE_COMMAND_PHASE = -10, // This one isn't used anywhere
FSG_STATE_DATA_PHASE,
FSG_STATE_STATUS_PHASE,
FSG_STATE_IDLE = 0,
FSG_STATE_ABORT_BULK_OUT,
FSG_STATE_RESET,
FSG_STATE_INTERFACE_CHANGE,
FSG_STATE_CONFIG_CHANGE,
FSG_STATE_DISCONNECT,
FSG_STATE_EXIT,
FSG_STATE_TERMINATED
};
enum data_direction {
DATA_DIR_UNKNOWN = 0,
DATA_DIR_FROM_HOST,
DATA_DIR_TO_HOST,
DATA_DIR_NONE
};
struct fsg_dev {
/* lock protects: state, all the req_busy's, and cbbuf_cmnd */
spinlock_t lock;
struct usb_gadget *gadget;
/* filesem protects: backing files in use */
struct rw_semaphore filesem;
/* reference counting: wait until all LUNs are released */
struct kref ref;
struct usb_ep *ep0; // Handy copy of gadget->ep0
struct usb_request *ep0req; // For control responses
unsigned int ep0_req_tag;
const char *ep0req_name;
struct usb_request *intreq; // For interrupt responses
int intreq_busy;
struct fsg_buffhd *intr_buffhd;
unsigned int bulk_out_maxpacket;
enum fsg_state state; // For exception handling
unsigned int exception_req_tag;
u8 config, new_config;
unsigned int running : 1;
unsigned int bulk_in_enabled : 1;
unsigned int bulk_out_enabled : 1;
unsigned int intr_in_enabled : 1;
unsigned int phase_error : 1;
unsigned int short_packet_received : 1;
unsigned int bad_lun_okay : 1;
unsigned long atomic_bitflags;
#define REGISTERED 0
#define IGNORE_BULK_OUT 1
#define SUSPENDED 2
struct usb_ep *bulk_in;
struct usb_ep *bulk_out;
struct usb_ep *intr_in;
struct fsg_buffhd *next_buffhd_to_fill;
struct fsg_buffhd *next_buffhd_to_drain;
struct fsg_buffhd buffhds[NUM_BUFFERS];
int thread_wakeup_needed;
struct completion thread_notifier;
struct task_struct *thread_task;
int cmnd_size;
u8 cmnd[MAX_COMMAND_SIZE];
enum data_direction data_dir;
u32 data_size;
u32 data_size_from_cmnd;
u32 tag;
unsigned int lun;
u32 residue;
u32 usb_amount_left;
/* The CB protocol offers no way for a host to know when a command
* has completed. As a result the next command may arrive early,
* and we will still have to handle it. For that reason we need
* a buffer to store new commands when using CB (or CBI, which
* does not oblige a host to wait for command completion either). */
int cbbuf_cmnd_size;
u8 cbbuf_cmnd[MAX_COMMAND_SIZE];
unsigned int nluns;
struct lun *luns;
struct lun *curlun;
};
typedef void (*fsg_routine_t)(struct fsg_dev *);
static int exception_in_progress(struct fsg_dev *fsg)
{
return (fsg->state > FSG_STATE_IDLE);
}
/* Make bulk-out requests be divisible by the maxpacket size */
static void set_bulk_out_req_length(struct fsg_dev *fsg,
struct fsg_buffhd *bh, unsigned int length)
{
unsigned int rem;
bh->bulk_out_intended_length = length;
rem = length % fsg->bulk_out_maxpacket;
if (rem > 0)
length += fsg->bulk_out_maxpacket - rem;
bh->outreq->length = length;
}
static struct fsg_dev *the_fsg;
static struct usb_gadget_driver fsg_driver;
static void close_backing_file(struct lun *curlun);
/*-------------------------------------------------------------------------*/
#ifdef DUMP_MSGS
static void dump_msg(struct fsg_dev *fsg, const char *label,
const u8 *buf, unsigned int length)
{
if (length < 512) {
DBG(fsg, "%s, length %u:\n", label, length);
print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET,
16, 1, buf, length, 0);
}
}
static void dump_cdb(struct fsg_dev *fsg)
{}
#else
static void dump_msg(struct fsg_dev *fsg, const char *label,
const u8 *buf, unsigned int length)
{}
#ifdef VERBOSE_DEBUG
static void dump_cdb(struct fsg_dev *fsg)
{
print_hex_dump(KERN_DEBUG, "SCSI CDB: ", DUMP_PREFIX_NONE,
16, 1, fsg->cmnd, fsg->cmnd_size, 0);
}
#else
static void dump_cdb(struct fsg_dev *fsg)
{}
#endif /* VERBOSE_DEBUG */
#endif /* DUMP_MSGS */
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);
}
/*-------------------------------------------------------------------------*/
/* Routines for unaligned data access */
static u16 get_be16(u8 *buf)
{
return ((u16) buf[0] << 8) | ((u16) buf[1]);
}
static u32 get_be32(u8 *buf)
{
return ((u32) buf[0] << 24) | ((u32) buf[1] << 16) |
((u32) buf[2] << 8) | ((u32) buf[3]);
}
static void put_be16(u8 *buf, u16 val)
{
buf[0] = val >> 8;
buf[1] = val;
}
static void put_be32(u8 *buf, u32 val)
{
buf[0] = val >> 24;
buf[1] = val >> 16;
buf[2] = val >> 8;
buf[3] = val & 0xff;
}
/*-------------------------------------------------------------------------*/
/*
* DESCRIPTORS ... most are static, but strings and (full) configuration
* descriptors are built on demand. Also the (static) config and interface
* descriptors are adjusted during fsg_bind().
*/
#define STRING_MANUFACTURER 1
#define STRING_PRODUCT 2
#define STRING_SERIAL 3
#define STRING_CONFIG 4
#define STRING_INTERFACE 5
/* There is only one configuration. */
#define CONFIG_VALUE 1
static struct usb_device_descriptor
device_desc = {
.bLength = sizeof device_desc,
.bDescriptorType = USB_DT_DEVICE,
.bcdUSB = cpu_to_le16(0x0200),
.bDeviceClass = USB_CLASS_PER_INTERFACE,
/* The next three values can be overridden by module parameters */
.idVendor = cpu_to_le16(DRIVER_VENDOR_ID),
.idProduct = cpu_to_le16(DRIVER_PRODUCT_ID),
.bcdDevice = cpu_to_le16(0xffff),
.iManufacturer = STRING_MANUFACTURER,
.iProduct = STRING_PRODUCT,
.iSerialNumber = STRING_SERIAL,
.bNumConfigurations = 1,
};
static struct usb_config_descriptor
config_desc = {
.bLength = sizeof config_desc,
.bDescriptorType = USB_DT_CONFIG,
/* wTotalLength computed by usb_gadget_config_buf() */
.bNumInterfaces = 1,
.bConfigurationValue = CONFIG_VALUE,
.iConfiguration = STRING_CONFIG,
.bmAttributes = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
.bMaxPower = CONFIG_USB_GADGET_VBUS_DRAW / 2,
};
static struct usb_otg_descriptor
otg_desc = {
.bLength = sizeof(otg_desc),
.bDescriptorType = USB_DT_OTG,
.bmAttributes = USB_OTG_SRP,
};
/* There is only one interface. */
static struct usb_interface_descriptor
intf_desc = {
.bLength = sizeof intf_desc,
.bDescriptorType = USB_DT_INTERFACE,
.bNumEndpoints = 2, // Adjusted during fsg_bind()
.bInterfaceClass = USB_CLASS_MASS_STORAGE,
.bInterfaceSubClass = USB_SC_SCSI, // Adjusted during fsg_bind()
.bInterfaceProtocol = USB_PR_BULK, // Adjusted during fsg_bind()
.iInterface = STRING_INTERFACE,
};
/* Three full-speed endpoint descriptors: bulk-in, bulk-out,
* and interrupt-in. */
static struct usb_endpoint_descriptor
fs_bulk_in_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
/* wMaxPacketSize set by autoconfiguration */
};
static struct usb_endpoint_descriptor
fs_bulk_out_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
/* wMaxPacketSize set by autoconfiguration */
};
static struct usb_endpoint_descriptor
fs_intr_in_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = cpu_to_le16(2),
.bInterval = 32, // frames -> 32 ms
};
static const struct usb_descriptor_header *fs_function[] = {
(struct usb_descriptor_header *) &otg_desc,
(struct usb_descriptor_header *) &intf_desc,
(struct usb_descriptor_header *) &fs_bulk_in_desc,
(struct usb_descriptor_header *) &fs_bulk_out_desc,
(struct usb_descriptor_header *) &fs_intr_in_desc,
NULL,
};
#define FS_FUNCTION_PRE_EP_ENTRIES 2
/*
* USB 2.0 devices need to expose both high speed and full speed
* descriptors, unless they only run at full speed.
*
* That means alternate endpoint descriptors (bigger packets)
* and a "device qualifier" ... plus more construction options
* for the config descriptor.
*/
static struct usb_qualifier_descriptor
dev_qualifier = {
.bLength = sizeof dev_qualifier,
.bDescriptorType = USB_DT_DEVICE_QUALIFIER,
.bcdUSB = cpu_to_le16(0x0200),
.bDeviceClass = USB_CLASS_PER_INTERFACE,
.bNumConfigurations = 1,
};
static struct usb_endpoint_descriptor
hs_bulk_in_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
/* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = cpu_to_le16(512),
};
static struct usb_endpoint_descriptor
hs_bulk_out_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
/* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = cpu_to_le16(512),
.bInterval = 1, // NAK every 1 uframe
};
static struct usb_endpoint_descriptor
hs_intr_in_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
/* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = cpu_to_le16(2),
.bInterval = 9, // 2**(9-1) = 256 uframes -> 32 ms
};
static const struct usb_descriptor_header *hs_function[] = {
(struct usb_descriptor_header *) &otg_desc,
(struct usb_descriptor_header *) &intf_desc,
(struct usb_descriptor_header *) &hs_bulk_in_desc,
(struct usb_descriptor_header *) &hs_bulk_out_desc,
(struct usb_descriptor_header *) &hs_intr_in_desc,
NULL,
};
#define HS_FUNCTION_PRE_EP_ENTRIES 2
/* Maxpacket and other transfer characteristics vary by speed. */
static struct usb_endpoint_descriptor *
ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *fs,
struct usb_endpoint_descriptor *hs)
{
if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
return hs;
return fs;
}
/* The CBI specification limits the serial string to 12 uppercase hexadecimal
* characters. */
static char manufacturer[64];
static char serial[13];
/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
static struct usb_string strings[] = {
{STRING_MANUFACTURER, manufacturer},
{STRING_PRODUCT, longname},
{STRING_SERIAL, serial},
{STRING_CONFIG, "Self-powered"},
{STRING_INTERFACE, "Mass Storage"},
{}
};
static struct usb_gadget_strings stringtab = {
.language = 0x0409, // en-us
.strings = strings,
};
/*
* Config descriptors must agree with the code that sets configurations
* and with code managing interfaces and their altsettings. They must
* also handle different speeds and other-speed requests.
*/
static int populate_config_buf(struct usb_gadget *gadget,
u8 *buf, u8 type, unsigned index)
{
enum usb_device_speed speed = gadget->speed;
int len;
const struct usb_descriptor_header **function;
if (index > 0)
return -EINVAL;
if (gadget_is_dualspeed(gadget) && type == USB_DT_OTHER_SPEED_CONFIG)
speed = (USB_SPEED_FULL + USB_SPEED_HIGH) - speed;
if (gadget_is_dualspeed(gadget) && speed == USB_SPEED_HIGH)
function = hs_function;
else
function = fs_function;
/* for now, don't advertise srp-only devices */
if (!gadget_is_otg(gadget))
function++;
len = usb_gadget_config_buf(&config_desc, buf, EP0_BUFSIZE, function);
((struct usb_config_descriptor *) buf)->bDescriptorType = type;
return len;
}
/*-------------------------------------------------------------------------*/
/* These routines may be called in process context or in_irq */
/* Caller must hold fsg->lock */
static void wakeup_thread(struct fsg_dev *fsg)
{
/* Tell the main thread that something has happened */
fsg->thread_wakeup_needed = 1;
if (fsg->thread_task)
wake_up_process(fsg->thread_task);
}
static void raise_exception(struct fsg_dev *fsg, 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(&fsg->lock, flags);
if (fsg->state <= new_state) {
fsg->exception_req_tag = fsg->ep0_req_tag;
fsg->state = new_state;
if (fsg->thread_task)
send_sig_info(SIGUSR1, SEND_SIG_FORCED,
fsg->thread_task);
}
spin_unlock_irqrestore(&fsg->lock, flags);
}
/*-------------------------------------------------------------------------*/
/* The disconnect callback and ep0 routines. These always run in_irq,
* except that ep0_queue() is called in the main thread to acknowledge
* completion of various requests: set config, set interface, and
* Bulk-only device reset. */
static void fsg_disconnect(struct usb_gadget *gadget)
{
struct fsg_dev *fsg = get_gadget_data(gadget);
DBG(fsg, "disconnect or port reset\n");
raise_exception(fsg, FSG_STATE_DISCONNECT);
}
static int ep0_queue(struct fsg_dev *fsg)
{
int rc;
rc = usb_ep_queue(fsg->ep0, fsg->ep0req, GFP_ATOMIC);
if (rc != 0 && rc != -ESHUTDOWN) {
/* We can't do much more than wait for a reset */
WARNING(fsg, "error in submission: %s --> %d\n",
fsg->ep0->name, rc);
}
return rc;
}
static void ep0_complete(struct usb_ep *ep, struct usb_request *req)
{
struct fsg_dev *fsg = ep->driver_data;
if (req->actual > 0)
dump_msg(fsg, fsg->ep0req_name, req->buf, req->actual);
if (req->status || req->actual != req->length)
DBG(fsg, "%s --> %d, %u/%u\n", __func__,
req->status, req->actual, req->length);
if (req->status == -ECONNRESET) // Request was cancelled
usb_ep_fifo_flush(ep);
if (req->status == 0 && req->context)
((fsg_routine_t) (req->context))(fsg);
}
/*-------------------------------------------------------------------------*/
/* Bulk and interrupt endpoint completion handlers.
* These always run in_irq. */
static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
{
struct fsg_dev *fsg = ep->driver_data;
struct fsg_buffhd *bh = req->context;
if (req->status || req->actual != req->length)
DBG(fsg, "%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(&fsg->lock);
bh->inreq_busy = 0;
bh->state = BUF_STATE_EMPTY;
wakeup_thread(fsg);
spin_unlock(&fsg->lock);
}
static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
{
struct fsg_dev *fsg = ep->driver_data;
struct fsg_buffhd *bh = req->context;
dump_msg(fsg, "bulk-out", req->buf, req->actual);
if (req->status || req->actual != bh->bulk_out_intended_length)
DBG(fsg, "%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(&fsg->lock);
bh->outreq_busy = 0;
bh->state = BUF_STATE_FULL;
wakeup_thread(fsg);
spin_unlock(&fsg->lock);
}
#ifdef CONFIG_USB_FILE_STORAGE_TEST
static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
{
struct fsg_dev *fsg = ep->driver_data;
struct fsg_buffhd *bh = req->context;
if (req->status || req->actual != req->length)
DBG(fsg, "%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(&fsg->lock);
fsg->intreq_busy = 0;
bh->state = BUF_STATE_EMPTY;
wakeup_thread(fsg);
spin_unlock(&fsg->lock);
}
#else
static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
{}
#endif /* CONFIG_USB_FILE_STORAGE_TEST */
/*-------------------------------------------------------------------------*/
/* Ep0 class-specific handlers. These always run in_irq. */
#ifdef CONFIG_USB_FILE_STORAGE_TEST
static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{
struct usb_request *req = fsg->ep0req;
static u8 cbi_reset_cmnd[6] = {
SC_SEND_DIAGNOSTIC, 4, 0xff, 0xff, 0xff, 0xff};
/* Error in command transfer? */
if (req->status || req->length != req->actual ||
req->actual < 6 || req->actual > MAX_COMMAND_SIZE) {
/* Not all controllers allow a protocol stall after
* receiving control-out data, but we'll try anyway. */
fsg_set_halt(fsg, fsg->ep0);
return; // Wait for reset
}
/* Is it the special reset command? */
if (req->actual >= sizeof cbi_reset_cmnd &&
memcmp(req->buf, cbi_reset_cmnd,
sizeof cbi_reset_cmnd) == 0) {
/* Raise an exception to stop the current operation
* and reinitialize our state. */
DBG(fsg, "cbi reset request\n");
raise_exception(fsg, FSG_STATE_RESET);
return;
}
VDBG(fsg, "CB[I] accept device-specific command\n");
spin_lock(&fsg->lock);
/* Save the command for later */
if (fsg->cbbuf_cmnd_size)
WARNING(fsg, "CB[I] overwriting previous command\n");
fsg->cbbuf_cmnd_size = req->actual;
memcpy(fsg->cbbuf_cmnd, req->buf, fsg->cbbuf_cmnd_size);
wakeup_thread(fsg);
spin_unlock(&fsg->lock);
}
#else
static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{}
#endif /* CONFIG_USB_FILE_STORAGE_TEST */
static int class_setup_req(struct fsg_dev *fsg,
const struct usb_ctrlrequest *ctrl)
{
struct usb_request *req = fsg->ep0req;
int value = -EOPNOTSUPP;
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->config)
return value;
/* Handle Bulk-only class-specific requests */
if (transport_is_bbb()) {
switch (ctrl->bRequest) {
case USB_BULK_RESET_REQUEST:
if (ctrl->bRequestType != (USB_DIR_OUT |
USB_TYPE_CLASS | USB_RECIP_INTERFACE))
break;
if (w_index != 0 || w_value != 0) {
value = -EDOM;
break;
}
/* Raise an exception to stop the current operation
* and reinitialize our state. */
DBG(fsg, "bulk reset request\n");
raise_exception(fsg, FSG_STATE_RESET);
value = DELAYED_STATUS;
break;
case USB_BULK_GET_MAX_LUN_REQUEST:
if (ctrl->bRequestType != (USB_DIR_IN |
USB_TYPE_CLASS | USB_RECIP_INTERFACE))
break;
if (w_index != 0 || w_value != 0) {
value = -EDOM;
break;
}
VDBG(fsg, "get max LUN\n");
*(u8 *) req->buf = fsg->nluns - 1;
value = 1;
break;
}
}
/* Handle CBI class-specific requests */
else {
switch (ctrl->bRequest) {
case USB_CBI_ADSC_REQUEST:
if (ctrl->bRequestType != (USB_DIR_OUT |
USB_TYPE_CLASS | USB_RECIP_INTERFACE))
break;
if (w_index != 0 || w_value != 0) {
value = -EDOM;
break;
}
if (w_length > MAX_COMMAND_SIZE) {
value = -EOVERFLOW;
break;
}
value = w_length;
fsg->ep0req->context = received_cbi_adsc;
break;
}
}
if (value == -EOPNOTSUPP)
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 value;
}
/*-------------------------------------------------------------------------*/
/* Ep0 standard request handlers. These always run in_irq. */
static int standard_setup_req(struct fsg_dev *fsg,
const struct usb_ctrlrequest *ctrl)
{
struct usb_request *req = fsg->ep0req;
int value = -EOPNOTSUPP;
u16 w_index = le16_to_cpu(ctrl->wIndex);
u16 w_value = le16_to_cpu(ctrl->wValue);
/* Usually this just stores reply data in the pre-allocated ep0 buffer,
* but config change events will also reconfigure hardware. */
switch (ctrl->bRequest) {
case USB_REQ_GET_DESCRIPTOR:
if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
USB_RECIP_DEVICE))
break;
switch (w_value >> 8) {
case USB_DT_DEVICE:
VDBG(fsg, "get device descriptor\n");
value = sizeof device_desc;
memcpy(req->buf, &device_desc, value);
break;
case USB_DT_DEVICE_QUALIFIER:
VDBG(fsg, "get device qualifier\n");
if (!gadget_is_dualspeed(fsg->gadget))
break;
value = sizeof dev_qualifier;
memcpy(req->buf, &dev_qualifier, value);
break;
case USB_DT_OTHER_SPEED_CONFIG:
VDBG(fsg, "get other-speed config descriptor\n");
if (!gadget_is_dualspeed(fsg->gadget))
break;
goto get_config;
case USB_DT_CONFIG:
VDBG(fsg, "get configuration descriptor\n");
get_config:
value = populate_config_buf(fsg->gadget,
req->buf,
w_value >> 8,
w_value & 0xff);
break;
case USB_DT_STRING:
VDBG(fsg, "get string descriptor\n");
/* wIndex == language code */
value = usb_gadget_get_string(&stringtab,
w_value & 0xff, req->buf);
break;
}
break;
/* One config, two speeds */
case USB_REQ_SET_CONFIGURATION:
if (ctrl->bRequestType != (USB_DIR_OUT | USB_TYPE_STANDARD |
USB_RECIP_DEVICE))
break;
VDBG(fsg, "set configuration\n");
if (w_value == CONFIG_VALUE || w_value == 0) {
fsg->new_config = w_value;
/* Raise an exception to wipe out previous transaction
* state (queued bufs, etc) and set the new config. */
raise_exception(fsg, FSG_STATE_CONFIG_CHANGE);
value = DELAYED_STATUS;
}
break;
case USB_REQ_GET_CONFIGURATION:
if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
USB_RECIP_DEVICE))
break;
VDBG(fsg, "get configuration\n");
*(u8 *) req->buf = fsg->config;
value = 1;
break;
case USB_REQ_SET_INTERFACE:
if (ctrl->bRequestType != (USB_DIR_OUT| USB_TYPE_STANDARD |
USB_RECIP_INTERFACE))
break;
if (fsg->config && w_index == 0) {
/* Raise an exception to wipe out previous transaction
* state (queued bufs, etc) and install the new
* interface altsetting. */
raise_exception(fsg, FSG_STATE_INTERFACE_CHANGE);
value = DELAYED_STATUS;
}
break;
case USB_REQ_GET_INTERFACE:
if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
USB_RECIP_INTERFACE))
break;
if (!fsg->config)
break;
if (w_index != 0) {
value = -EDOM;
break;
}
VDBG(fsg, "get interface\n");
*(u8 *) req->buf = 0;
value = 1;
break;
default:
VDBG(fsg,
"unknown control req %02x.%02x v%04x i%04x l%u\n",
ctrl->bRequestType, ctrl->bRequest,
w_value, w_index, le16_to_cpu(ctrl->wLength));
}
return value;
}
static int fsg_setup(struct usb_gadget *gadget,
const struct usb_ctrlrequest *ctrl)
{
struct fsg_dev *fsg = get_gadget_data(gadget);
int rc;
int w_length = le16_to_cpu(ctrl->wLength);
++fsg->ep0_req_tag; // Record arrival of a new request
fsg->ep0req->context = NULL;
fsg->ep0req->length = 0;
dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS)
rc = class_setup_req(fsg, ctrl);
else
rc = standard_setup_req(fsg, ctrl);
/* Respond with data/status or defer until later? */
if (rc >= 0 && rc != DELAYED_STATUS) {
rc = min(rc, w_length);
fsg->ep0req->length = rc;
fsg->ep0req->zero = rc < w_length;
fsg->ep0req_name = (ctrl->bRequestType & USB_DIR_IN ?
"ep0-in" : "ep0-out");
rc = ep0_queue(fsg);
}
/* Device either stalls (rc < 0) or reports success */
return rc;
}
/*-------------------------------------------------------------------------*/
/* 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);
else if (ep == fsg->intr_in)
dump_msg(fsg, "intr-in", req->buf, req->length);
spin_lock_irq(&fsg->lock);
*pbusy = 1;
*state = BUF_STATE_BUSY;
spin_unlock_irq(&fsg->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 int sleep_thread(struct fsg_dev *fsg)
{
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 (fsg->thread_wakeup_needed)
break;
schedule();
}
__set_current_state(TASK_RUNNING);
fsg->thread_wakeup_needed = 0;
return rc;
}
/*-------------------------------------------------------------------------*/
static int do_read(struct fsg_dev *fsg)
{
struct lun *curlun = fsg->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 (fsg->cmnd[0] == SC_READ_6)
lba = (fsg->cmnd[1] << 16) | get_be16(&fsg->cmnd[2]);
else {
lba = get_be32(&fsg->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 ((fsg->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 = fsg->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((unsigned int) amount_left, mod_data.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 = fsg->next_buffhd_to_fill;
while (bh->state != BUF_STATE_EMPTY) {
rc = sleep_thread(fsg);
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;
fsg->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;
start_transfer(fsg, fsg->bulk_in, bh->inreq,
&bh->inreq_busy, &bh->state);
fsg->next_buffhd_to_fill = bh->next;
}
return -EIO; // No default reply
}
/*-------------------------------------------------------------------------*/
static int do_write(struct fsg_dev *fsg)
{
struct lun *curlun = fsg->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 (fsg->cmnd[0] == SC_WRITE_6)
lba = (fsg->cmnd[1] << 16) | get_be16(&fsg->cmnd[2]);
else {
lba = get_be32(&fsg->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 ((fsg->cmnd[1] & ~0x18) != 0) {
curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
return -EINVAL;
}
if (fsg->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 = amount_left_to_write = fsg->data_size_from_cmnd;
while (amount_left_to_write > 0) {
/* Queue a request for more data from the host */
bh = fsg->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, mod_data.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;
fsg->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 = bh->bulk_out_intended_length =
amount;
bh->outreq->short_not_ok = 1;
start_transfer(fsg, fsg->bulk_out, bh->outreq,
&bh->outreq_busy, &bh->state);
fsg->next_buffhd_to_fill = bh->next;
continue;
}
/* Write the received data to the backing file */
bh = fsg->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();
fsg->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;
fsg->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) {
fsg->short_packet_received = 1;
break;
}
continue;
}
/* Wait for something to happen */
rc = sleep_thread(fsg);
if (rc)
return rc;
}
return -EIO; // No default reply
}
/*-------------------------------------------------------------------------*/
/* Sync the file data, don't bother with the metadata.
* This code was copied from fs/buffer.c:sys_fdatasync(). */
static int fsync_sub(struct lun *curlun)
{
struct file *filp = curlun->filp;
if (curlun->ro || !filp)
return 0;
return vfs_fsync(filp, filp->f_path.dentry, 1);
}
static void fsync_all(struct fsg_dev *fsg)
{
int i;
for (i = 0; i < fsg->nluns; ++i)
fsync_sub(&fsg->luns[i]);
}
static int do_synchronize_cache(struct fsg_dev *fsg)
{
struct lun *curlun = fsg->curlun;
int rc;
/* We ignore the requested LBA and write out all file's
* dirty data buffers. */
rc = fsync_sub(curlun);
if (rc)
curlun->sense_data = SS_WRITE_ERROR;
return 0;
}
/*-------------------------------------------------------------------------*/
static void invalidate_sub(struct 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_inode_pages -> %ld\n", rc);
}
static int do_verify(struct fsg_dev *fsg)
{
struct lun *curlun = fsg->curlun;
u32 lba;
u32 verification_length;
struct fsg_buffhd *bh = fsg->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_be32(&fsg->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 ((fsg->cmnd[1] & ~0x10) != 0) {
curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
return -EINVAL;
}
verification_length = get_be16(&fsg->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 */
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((unsigned int) amount_left, mod_data.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_dev *fsg, struct fsg_buffhd *bh)
{
u8 *buf = (u8 *) bh->buf;
static char vendor_id[] = "Linux ";
static char product_disk_id[] = "File-Stor Gadget";
static char product_cdrom_id[] = "File-CD Gadget ";
if (!fsg->curlun) { // Unsupported LUNs are okay
fsg->bad_lun_okay = 1;
memset(buf, 0, 36);
buf[0] = 0x7f; // Unsupported, no device-type
buf[4] = 31; // Additional length
return 36;
}
memset(buf, 0, 8);
buf[0] = (mod_data.cdrom ? TYPE_CDROM : TYPE_DISK);
if (mod_data.removable)
buf[1] = 0x80;
buf[2] = 2; // ANSI SCSI level 2
buf[3] = 2; // SCSI-2 INQUIRY data format
buf[4] = 31; // Additional length
// No special options
sprintf(buf + 8, "%-8s%-16s%04x", vendor_id,
(mod_data.cdrom ? product_cdrom_id :
product_disk_id),
mod_data.release);
return 36;
}
static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{
struct lun *curlun = fsg->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
fsg->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_be32(&buf[3], sdinfo); // 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_dev *fsg, struct fsg_buffhd *bh)
{
struct lun *curlun = fsg->curlun;
u32 lba = get_be32(&fsg->cmnd[2]);
int pmi = fsg->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_be32(&buf[0], curlun->num_sectors - 1); // Max logical block
put_be32(&buf[4], 512); // Block length
return 8;
}
static void store_cdrom_address(u8 *dest, int msf, u32 addr)
{
if (msf) {
/* Convert to Minutes-Seconds-Frames */
addr >>= 2; /* Convert to 2048-byte frames */
addr += 2*75; /* Lead-in occupies 2 seconds */
dest[3] = addr % 75; /* Frames */
addr /= 75;
dest[2] = addr % 60; /* Seconds */
addr /= 60;
dest[1] = addr; /* Minutes */
dest[0] = 0; /* Reserved */
} else {
/* Absolute sector */
put_be32(dest, addr);
}
}
static int do_read_header(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{
struct lun *curlun = fsg->curlun;
int msf = fsg->cmnd[1] & 0x02;
u32 lba = get_be32(&fsg->cmnd[2]);
u8 *buf = (u8 *) bh->buf;
if ((fsg->cmnd[1] & ~0x02) != 0) { /* 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_dev *fsg, struct fsg_buffhd *bh)
{
struct lun *curlun = fsg->curlun;
int msf = fsg->cmnd[1] & 0x02;
int start_track = fsg->cmnd[6];
u8 *buf = (u8 *) bh->buf;
if ((fsg->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_dev *fsg, struct fsg_buffhd *bh)
{
struct lun *curlun = fsg->curlun;
int mscmnd = fsg->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 ((fsg->cmnd[1] & ~0x08) != 0) { // Mask away DBD
curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
return -EINVAL;
}
pc = fsg->cmnd[2] >> 6;
page_code = fsg->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 == SC_MODE_SENSE_6) {
buf[2] = (curlun->ro ? 0x80 : 0x00); // WP, DPOFUA
buf += 4;
limit = 255;
} else { // SC_MODE_SENSE_10
buf[3] = (curlun->ro ? 0x80 : 0x00); // WP, DPOFUA
buf += 8;
limit = 65535; // Should really be mod_data.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_be16(&buf[4], 0xffff); // Don't disable prefetch
// Minimum prefetch = 0
put_be16(&buf[8], 0xffff); // Maximum prefetch
put_be16(&buf[10], 0xffff); // 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 == SC_MODE_SENSE_6)
buf0[0] = len - 1;
else
put_be16(buf0, len - 2);
return len;
}
static int do_start_stop(struct fsg_dev *fsg)
{
struct lun *curlun = fsg->curlun;
int loej, start;
if (!mod_data.removable) {
curlun->sense_data = SS_INVALID_COMMAND;
return -EINVAL;
}
// int immed = fsg->cmnd[1] & 0x01;
loej = fsg->cmnd[4] & 0x02;
start = fsg->cmnd[4] & 0x01;
#ifdef CONFIG_USB_FILE_STORAGE_TEST
if ((fsg->cmnd[1] & ~0x01) != 0 || // Mask away Immed
(fsg->cmnd[4] & ~0x03) != 0) { // Mask LoEj, Start
curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
return -EINVAL;
}
if (!start) {
/* 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) { // Simulate an unload/eject
up_read(&fsg->filesem);
down_write(&fsg->filesem);
close_backing_file(curlun);
up_write(&fsg->filesem);
down_read(&fsg->filesem);
}
} else {
/* Our emulation doesn't support mounting; the medium is
* available for use as soon as it is loaded. */
if (!backing_file_is_open(curlun)) {
curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
return -EINVAL;
}
}
#endif
return 0;
}
static int do_prevent_allow(struct fsg_dev *fsg)
{
struct lun *curlun = fsg->curlun;
int prevent;
if (!mod_data.removable) {
curlun->sense_data = SS_INVALID_COMMAND;
return -EINVAL;
}
prevent = fsg->cmnd[4] & 0x01;
if ((fsg->cmnd[4] & ~0x01) != 0) { // Mask away Prevent
curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
return -EINVAL;
}
if (curlun->prevent_medium_removal && !prevent)
fsync_sub(curlun);
curlun->prevent_medium_removal = prevent;
return 0;
}
static int do_read_format_capacities(struct fsg_dev *fsg,
struct fsg_buffhd *bh)
{
struct lun *curlun = fsg->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_be32(&buf[0], curlun->num_sectors); // Number of blocks
put_be32(&buf[4], 512); // Block length
buf[4] = 0x02; // Current capacity
return 12;
}
static int do_mode_select(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{
struct lun *curlun = fsg->curlun;
/* We don't support MODE SELECT */
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 pad_with_zeros(struct fsg_dev *fsg)
{
struct fsg_buffhd *bh = fsg->next_buffhd_to_fill;
u32 nkeep = bh->inreq->length;
u32 nsend;
int rc;
bh->state = BUF_STATE_EMPTY; // For the first iteration
fsg->usb_amount_left = nkeep + fsg->residue;
while (fsg->usb_amount_left > 0) {
/* Wait for the next buffer to be free */
while (bh->state != BUF_STATE_EMPTY) {
rc = sleep_thread(fsg);
if (rc)
return rc;
}
nsend = min(fsg->usb_amount_left, (u32) mod_data.buflen);
memset(bh->buf + nkeep, 0, nsend - nkeep);
bh->inreq->length = nsend;
bh->inreq->zero = 0;
start_transfer(fsg, fsg->bulk_in, bh->inreq,
&bh->inreq_busy, &bh->state);
bh = fsg->next_buffhd_to_fill = bh->next;
fsg->usb_amount_left -= nsend;
nkeep = 0;
}
return 0;
}
static int throw_away_data(struct fsg_dev *fsg)
{
struct fsg_buffhd *bh;
u32 amount;
int rc;
while ((bh = fsg->next_buffhd_to_drain)->state != BUF_STATE_EMPTY ||
fsg->usb_amount_left > 0) {
/* Throw away the data in a filled buffer */
if (bh->state == BUF_STATE_FULL) {
smp_rmb();
bh->state = BUF_STATE_EMPTY;
fsg->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(fsg, FSG_STATE_ABORT_BULK_OUT);
return -EINTR;
}
continue;
}
/* Try to submit another request if we need one */
bh = fsg->next_buffhd_to_fill;
if (bh->state == BUF_STATE_EMPTY && fsg->usb_amount_left > 0) {
amount = min(fsg->usb_amount_left,
(u32) mod_data.buflen);
/* amount is always divisible by 512, hence by
* the bulk-out maxpacket size */
bh->outreq->length = bh->bulk_out_intended_length =
amount;
bh->outreq->short_not_ok = 1;
start_transfer(fsg, fsg->bulk_out, bh->outreq,
&bh->outreq_busy, &bh->state);
fsg->next_buffhd_to_fill = bh->next;
fsg->usb_amount_left -= amount;
continue;
}
/* Otherwise wait for something to happen */
rc = sleep_thread(fsg);
if (rc)
return rc;
}
return 0;
}
static int finish_reply(struct fsg_dev *fsg)
{
struct fsg_buffhd *bh = fsg->next_buffhd_to_fill;
int rc = 0;
switch (fsg->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 mustn't
* try to send or receive any data. So stall both bulk pipes
* if we can and wait for a reset. */
case DATA_DIR_UNKNOWN:
if (mod_data.can_stall) {
fsg_set_halt(fsg, fsg->bulk_out);
rc = halt_bulk_in_endpoint(fsg);
}
break;
/* All but the last buffer of data must have already been sent */
case DATA_DIR_TO_HOST:
if (fsg->data_size == 0)
; // Nothing to send
/* If there's no residue, simply send the last buffer */
else if (fsg->residue == 0) {
bh->inreq->zero = 0;
start_transfer(fsg, fsg->bulk_in, bh->inreq,
&bh->inreq_busy, &bh->state);
fsg->next_buffhd_to_fill = bh->next;
}
/* There is a residue. For CB and CBI, simply mark the end
* of the data with a short packet. However, if we are
* allowed to stall, there was no data at all (residue ==
* data_size), and the command failed (invalid LUN or
* sense data is set), then halt the bulk-in endpoint
* instead. */
else if (!transport_is_bbb()) {
if (mod_data.can_stall &&
fsg->residue == fsg->data_size &&
(!fsg->curlun || fsg->curlun->sense_data != SS_NO_SENSE)) {
bh->state = BUF_STATE_EMPTY;
rc = halt_bulk_in_endpoint(fsg);
} else {
bh->inreq->zero = 1;
start_transfer(fsg, fsg->bulk_in, bh->inreq,
&bh->inreq_busy, &bh->state);
fsg->next_buffhd_to_fill = bh->next;
}
}
/* For Bulk-only, if we're allowed to stall then send the
* short packet and halt the bulk-in endpoint. If we can't
* stall, pad out the remaining data with 0's. */
else {
if (mod_data.can_stall) {
bh->inreq->zero = 1;
start_transfer(fsg, fsg->bulk_in, bh->inreq,
&bh->inreq_busy, &bh->state);
fsg->next_buffhd_to_fill = bh->next;
rc = halt_bulk_in_endpoint(fsg);
} else
rc = pad_with_zeros(fsg);
}
break;
/* We have processed all we want from the data the host has sent.
* There may still be outstanding bulk-out requests. */
case DATA_DIR_FROM_HOST:
if (fsg->residue == 0)
; // Nothing to receive
/* Did the host stop sending unexpectedly early? */
else if (fsg->short_packet_received) {
raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
rc = -EINTR;
}
/* We haven't processed all the incoming data. Even though
* we may be allowed to stall, doing so would cause a race.
* The controller may already have ACK'ed all the remaining
* bulk-out packets, in which case the host wouldn't see a
* STALL. Not realizing the endpoint was halted, it wouldn't
* clear the halt -- leading to problems later on. */
#if 0
else if (mod_data.can_stall) {
fsg_set_halt(fsg, fsg->bulk_out);
raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
rc = -EINTR;
}
#endif
/* We can't stall. Read in the excess data and throw it
* all away. */
else
rc = throw_away_data(fsg);
break;
}
return rc;
}
static int send_status(struct fsg_dev *fsg)
{
struct lun *curlun = fsg->curlun;
struct fsg_buffhd *bh;
int rc;
u8 status = USB_STATUS_PASS;
u32 sd, sdinfo = 0;
/* Wait for the next buffer to become available */
bh = fsg->next_buffhd_to_fill;
while (bh->state != BUF_STATE_EMPTY) {
rc = sleep_thread(fsg);
if (rc)
return rc;
}
if (curlun) {
sd = curlun->sense_data;
sdinfo = curlun->sense_data_info;
} else if (fsg->bad_lun_okay)
sd = SS_NO_SENSE;
else
sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
if (fsg->phase_error) {
DBG(fsg, "sending phase-error status\n");
status = USB_STATUS_PHASE_ERROR;
sd = SS_INVALID_COMMAND;
} else if (sd != SS_NO_SENSE) {
DBG(fsg, "sending command-failure status\n");
status = USB_STATUS_FAIL;
VDBG(fsg, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
" info x%x\n",
SK(sd), ASC(sd), ASCQ(sd), sdinfo);
}
if (transport_is_bbb()) {
struct bulk_cs_wrap *csw = bh->buf;
/* Store and send the Bulk-only CSW */
csw->Signature = cpu_to_le32(USB_BULK_CS_SIG);
csw->Tag = fsg->tag;
csw->Residue = cpu_to_le32(fsg->residue);
csw->Status = status;
bh->inreq->length = USB_BULK_CS_WRAP_LEN;
bh->inreq->zero = 0;
start_transfer(fsg, fsg->bulk_in, bh->inreq,
&bh->inreq_busy, &bh->state);
} else if (mod_data.transport_type == USB_PR_CB) {
/* Control-Bulk transport has no status phase! */
return 0;
} else { // USB_PR_CBI
struct interrupt_data *buf = bh->buf;
/* Store and send the Interrupt data. UFI sends the ASC
* and ASCQ bytes. Everything else sends a Type (which
* is always 0) and the status Value. */
if (mod_data.protocol_type == USB_SC_UFI) {
buf->bType = ASC(sd);
buf->bValue = ASCQ(sd);
} else {
buf->bType = 0;
buf->bValue = status;
}
fsg->intreq->length = CBI_INTERRUPT_DATA_LEN;
fsg->intr_buffhd = bh; // Point to the right buffhd
fsg->intreq->buf = bh->inreq->buf;
fsg->intreq->context = bh;
start_transfer(fsg, fsg->intr_in, fsg->intreq,
&fsg->intreq_busy, &bh->state);
}
fsg->next_buffhd_to_fill = bh->next;
return 0;
}
/*-------------------------------------------------------------------------*/
/* Check whether the command is properly formed and whether its data size
* and direction agree with the values we already have. */
static int check_command(struct fsg_dev *fsg, int cmnd_size,
enum data_direction data_dir, unsigned int mask,
int needs_medium, const char *name)
{
int i;
int lun = fsg->cmnd[1] >> 5;
static const char dirletter[4] = {'u', 'o', 'i', 'n'};
char hdlen[20];
struct lun *curlun;
/* Adjust the expected cmnd_size for protocol encapsulation padding.
* Transparent SCSI doesn't pad. */
if (protocol_is_scsi())
;
/* There's some disagreement as to whether RBC pads commands or not.
* We'll play it safe and accept either form. */
else if (mod_data.protocol_type == USB_SC_RBC) {
if (fsg->cmnd_size == 12)
cmnd_size = 12;
/* All the other protocols pad to 12 bytes */
} else
cmnd_size = 12;
hdlen[0] = 0;
if (fsg->data_dir != DATA_DIR_UNKNOWN)
sprintf(hdlen, ", H%c=%u", dirletter[(int) fsg->data_dir],
fsg->data_size);
VDBG(fsg, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
name, cmnd_size, dirletter[(int) data_dir],
fsg->data_size_from_cmnd, fsg->cmnd_size, hdlen);
/* We can't reply at all until we know the correct data direction
* and size. */
if (fsg->data_size_from_cmnd == 0)
data_dir = DATA_DIR_NONE;
if (fsg->data_dir == DATA_DIR_UNKNOWN) { // CB or CBI
fsg->data_dir = data_dir;
fsg->data_size = fsg->data_size_from_cmnd;
} else { // Bulk-only
if (fsg->data_size < fsg->data_size_from_cmnd) {
/* Host data size < Device data size is a phase error.
* Carry out the command, but only transfer as much
* as we are allowed. */
fsg->data_size_from_cmnd = fsg->data_size;
fsg->phase_error = 1;
}
}
fsg->residue = fsg->usb_amount_left = fsg->data_size;
/* Conflicting data directions is a phase error */
if (fsg->data_dir != data_dir && fsg->data_size_from_cmnd > 0) {
fsg->phase_error = 1;
return -EINVAL;
}
/* Verify the length of the command itself */
if (cmnd_size != fsg->cmnd_size) {
/* Special case workaround: There are plenty of buggy SCSI
* implementations. Many have issues with cbw->Length
* field passing a wrong command size. For those cases we
* always try to work around the problem by using the length
* sent by the host side provided it is at least as large
* as the correct command length.
* Examples of such cases would be MS-Windows, which issues
* REQUEST SENSE with cbw->Length == 12 where it should
* be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
* REQUEST SENSE with cbw->Length == 10 where it should
* be 6 as well.
*/
if (cmnd_size <= fsg->cmnd_size) {
DBG(fsg, "%s is buggy! Expected length %d "
"but we got %d\n", name,
cmnd_size, fsg->cmnd_size);
cmnd_size = fsg->cmnd_size;
} else {
fsg->phase_error = 1;
return -EINVAL;
}
}
/* Check that the LUN values are consistent */
if (transport_is_bbb()) {
if (fsg->lun != lun)
DBG(fsg, "using LUN %d from CBW, "
"not LUN %d from CDB\n",
fsg->lun, lun);
} else
fsg->lun = lun; // Use LUN from the command
/* Check the LUN */
if (fsg->lun >= 0 && fsg->lun < fsg->nluns) {
fsg->curlun = curlun = &fsg->luns[fsg->lun];
if (fsg->cmnd[0] != SC_REQUEST_SENSE) {
curlun->sense_data = SS_NO_SENSE;
curlun->sense_data_info = 0;
curlun->info_valid = 0;
}
} else {
fsg->curlun = curlun = NULL;
fsg->bad_lun_okay = 0;
/* INQUIRY and REQUEST SENSE commands are explicitly allowed
* to use unsupported LUNs; all others may not. */
if (fsg->cmnd[0] != SC_INQUIRY &&
fsg->cmnd[0] != SC_REQUEST_SENSE) {
DBG(fsg, "unsupported LUN %d\n", fsg->lun);
return -EINVAL;
}
}
/* If a unit attention condition exists, only INQUIRY and
* REQUEST SENSE commands are allowed; anything else must fail. */
if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
fsg->cmnd[0] != SC_INQUIRY &&
fsg->cmnd[0] != SC_REQUEST_SENSE) {
curlun->sense_data = curlun->unit_attention_data;
curlun->unit_attention_data = SS_NO_SENSE;
return -EINVAL;
}
/* Check that only command bytes listed in the mask are non-zero */
fsg->cmnd[1] &= 0x1f; // Mask away the LUN
for (i = 1; i < cmnd_size; ++i) {
if (fsg->cmnd[i] && !(mask & (1 << i))) {
if (curlun)
curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
return -EINVAL;
}
}
/* If the medium isn't mounted and the command needs to access
* it, return an error. */
if (curlun && !backing_file_is_open(curlun) && needs_medium) {
curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
return -EINVAL;
}
return 0;
}
static int do_scsi_command(struct fsg_dev *fsg)
{
struct fsg_buffhd *bh;
int rc;
int reply = -EINVAL;
int i;
static char unknown[16];
dump_cdb(fsg);
/* Wait for the next buffer to become available for data or status */
bh = fsg->next_buffhd_to_drain = fsg->next_buffhd_to_fill;
while (bh->state != BUF_STATE_EMPTY) {
rc = sleep_thread(fsg);
if (rc)
return rc;
}
fsg->phase_error = 0;
fsg->short_packet_received = 0;
down_read(&fsg->filesem); // We're using the backing file
switch (fsg->cmnd[0]) {
case SC_INQUIRY:
fsg->data_size_from_cmnd = fsg->cmnd[4];
if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
(1<<4), 0,
"INQUIRY")) == 0)
reply = do_inquiry(fsg, bh);
break;
case SC_MODE_SELECT_6:
fsg->data_size_from_cmnd = fsg->cmnd[4];
if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST,
(1<<1) | (1<<4), 0,
"MODE SELECT(6)")) == 0)
reply = do_mode_select(fsg, bh);
break;
case SC_MODE_SELECT_10:
fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST,
(1<<1) | (3<<7), 0,
"MODE SELECT(10)")) == 0)
reply = do_mode_select(fsg, bh);
break;
case SC_MODE_SENSE_6:
fsg->data_size_from_cmnd = fsg->cmnd[4];
if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
(1<<1) | (1<<2) | (1<<4), 0,
"MODE SENSE(6)")) == 0)
reply = do_mode_sense(fsg, bh);
break;
case SC_MODE_SENSE_10:
fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
(1<<1) | (1<<2) | (3<<7), 0,
"MODE SENSE(10)")) == 0)
reply = do_mode_sense(fsg, bh);
break;
case SC_PREVENT_ALLOW_MEDIUM_REMOVAL:
fsg->data_size_from_cmnd = 0;
if ((reply = check_command(fsg, 6, DATA_DIR_NONE,
(1<<4), 0,
"PREVENT-ALLOW MEDIUM REMOVAL")) == 0)
reply = do_prevent_allow(fsg);
break;
case SC_READ_6:
i = fsg->cmnd[4];
fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
(7<<1) | (1<<4), 1,
"READ(6)")) == 0)
reply = do_read(fsg);
break;
case SC_READ_10:
fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]) << 9;
if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
(1<<1) | (0xf<<2) | (3<<7), 1,
"READ(10)")) == 0)
reply = do_read(fsg);
break;
case SC_READ_12:
fsg->data_size_from_cmnd = get_be32(&fsg->cmnd[6]) << 9;
if ((reply = check_command(fsg, 12, DATA_DIR_TO_HOST,
(1<<1) | (0xf<<2) | (0xf<<6), 1,
"READ(12)")) == 0)
reply = do_read(fsg);
break;
case SC_READ_CAPACITY:
fsg->data_size_from_cmnd = 8;
if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
(0xf<<2) | (1<<8), 1,
"READ CAPACITY")) == 0)
reply = do_read_capacity(fsg, bh);
break;
case SC_READ_HEADER:
if (!mod_data.cdrom)
goto unknown_cmnd;
fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
(3<<7) | (0x1f<<1), 1,
"READ HEADER")) == 0)
reply = do_read_header(fsg, bh);
break;
case SC_READ_TOC:
if (!mod_data.cdrom)
goto unknown_cmnd;
fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
(7<<6) | (1<<1), 1,
"READ TOC")) == 0)
reply = do_read_toc(fsg, bh);
break;
case SC_READ_FORMAT_CAPACITIES:
fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
(3<<7), 1,
"READ FORMAT CAPACITIES")) == 0)
reply = do_read_format_capacities(fsg, bh);
break;
case SC_REQUEST_SENSE:
fsg->data_size_from_cmnd = fsg->cmnd[4];
if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
(1<<4), 0,
"REQUEST SENSE")) == 0)
reply = do_request_sense(fsg, bh);
break;
case SC_START_STOP_UNIT:
fsg->data_size_from_cmnd = 0;
if ((reply = check_command(fsg, 6, DATA_DIR_NONE,
(1<<1) | (1<<4), 0,
"START-STOP UNIT")) == 0)
reply = do_start_stop(fsg);
break;
case SC_SYNCHRONIZE_CACHE:
fsg->data_size_from_cmnd = 0;
if ((reply = check_command(fsg, 10, DATA_DIR_NONE,
(0xf<<2) | (3<<7), 1,
"SYNCHRONIZE CACHE")) == 0)
reply = do_synchronize_cache(fsg);
break;
case SC_TEST_UNIT_READY:
fsg->data_size_from_cmnd = 0;
reply = check_command(fsg, 6, DATA_DIR_NONE,
0, 1,
"TEST UNIT READY");
break;
/* Although optional, this command is used by MS-Windows. We
* support a minimal version: BytChk must be 0. */
case SC_VERIFY:
fsg->data_size_from_cmnd = 0;
if ((reply = check_command(fsg, 10, DATA_DIR_NONE,
(1<<1) | (0xf<<2) | (3<<7), 1,
"VERIFY")) == 0)
reply = do_verify(fsg);
break;
case SC_WRITE_6:
i = fsg->cmnd[4];
fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST,
(7<<1) | (1<<4), 1,
"WRITE(6)")) == 0)
reply = do_write(fsg);
break;
case SC_WRITE_10:
fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]) << 9;
if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST,
(1<<1) | (0xf<<2) | (3<<7), 1,
"WRITE(10)")) == 0)
reply = do_write(fsg);
break;
case SC_WRITE_12:
fsg->data_size_from_cmnd = get_be32(&fsg->cmnd[6]) << 9;
if ((reply = check_command(fsg, 12, DATA_DIR_FROM_HOST,
(1<<1) | (0xf<<2) | (0xf<<6), 1,
"WRITE(12)")) == 0)
reply = do_write(fsg);
break;
/* Some mandatory commands that we recognize but don't implement.
* They don't mean much in this setting. It's left as an exercise
* for anyone interested to implement RESERVE and RELEASE in terms
* of Posix locks. */
case SC_FORMAT_UNIT:
case SC_RELEASE:
case SC_RESERVE:
case SC_SEND_DIAGNOSTIC:
// Fall through
default:
unknown_cmnd:
fsg->data_size_from_cmnd = 0;
sprintf(unknown, "Unknown x%02x", fsg->cmnd[0]);
if ((reply = check_command(fsg, fsg->cmnd_size,
DATA_DIR_UNKNOWN, 0xff, 0, unknown)) == 0) {
fsg->curlun->sense_data = SS_INVALID_COMMAND;
reply = -EINVAL;
}
break;
}
up_read(&fsg->filesem);
if (reply == -EINTR || signal_pending(current))
return -EINTR;
/* Set up the single reply buffer for finish_reply() */
if (reply == -EINVAL)
reply = 0; // Error reply length
if (reply >= 0 && fsg->data_dir == DATA_DIR_TO_HOST) {
reply = min((u32) reply, fsg->data_size_from_cmnd);
bh->inreq->length = reply;
bh->state = BUF_STATE_FULL;
fsg->residue -= reply;
} // Otherwise it's already set
return 0;
}
/*-------------------------------------------------------------------------*/
static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{
struct usb_request *req = bh->outreq;
struct bulk_cb_wrap *cbw = req->buf;
/* Was this a real packet? Should it be ignored? */
if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
return -EINVAL;
/* Is the CBW valid? */
if (req->actual != USB_BULK_CB_WRAP_LEN ||
cbw->Signature != cpu_to_le32(
USB_BULK_CB_SIG)) {
DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
req->actual,
le32_to_cpu(cbw->Signature));
/* The Bulk-only spec says we MUST stall the IN endpoint
* (6.6.1), so it's unavoidable. It also says we must
* retain this state until the next reset, but there's
* no way to tell the controller driver it should ignore
* Clear-Feature(HALT) requests.
*
* We aren't required to halt the OUT endpoint; instead
* we can simply accept and discard any data received
* until the next reset. */
wedge_bulk_in_endpoint(fsg);
set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
return -EINVAL;
}
/* Is the CBW meaningful? */
if (cbw->Lun >= MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG ||
cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
"cmdlen %u\n",
cbw->Lun, cbw->Flags, cbw->Length);
/* We can do anything we want here, so let's stall the
* bulk pipes if we are allowed to. */
if (mod_data.can_stall) {
fsg_set_halt(fsg, fsg->bulk_out);
halt_bulk_in_endpoint(fsg);
}
return -EINVAL;
}
/* Save the command for later */
fsg->cmnd_size = cbw->Length;
memcpy(fsg->cmnd, cbw->CDB, fsg->cmnd_size);
if (cbw->Flags & USB_BULK_IN_FLAG)
fsg->data_dir = DATA_DIR_TO_HOST;
else
fsg->data_dir = DATA_DIR_FROM_HOST;
fsg->data_size = le32_to_cpu(cbw->DataTransferLength);
if (fsg->data_size == 0)
fsg->data_dir = DATA_DIR_NONE;
fsg->lun = cbw->Lun;
fsg->tag = cbw->Tag;
return 0;
}
static int get_next_command(struct fsg_dev *fsg)
{
struct fsg_buffhd *bh;
int rc = 0;
if (transport_is_bbb()) {
/* Wait for the next buffer to become available */
bh = fsg->next_buffhd_to_fill;
while (bh->state != BUF_STATE_EMPTY) {
rc = sleep_thread(fsg);
if (rc)
return rc;
}
/* Queue a request to read a Bulk-only CBW */
set_bulk_out_req_length(fsg, bh, USB_BULK_CB_WRAP_LEN);
bh->outreq->short_not_ok = 1;
start_transfer(fsg, fsg->bulk_out, bh->outreq,
&bh->outreq_busy, &bh->state);
/* We will drain the buffer in software, which means we
* can reuse it for the next filling. No need to advance
* next_buffhd_to_fill. */
/* Wait for the CBW to arrive */
while (bh->state != BUF_STATE_FULL) {
rc = sleep_thread(fsg);
if (rc)
return rc;
}
smp_rmb();
rc = received_cbw(fsg, bh);
bh->state = BUF_STATE_EMPTY;
} else { // USB_PR_CB or USB_PR_CBI
/* Wait for the next command to arrive */
while (fsg->cbbuf_cmnd_size == 0) {
rc = sleep_thread(fsg);
if (rc)
return rc;
}
/* Is the previous status interrupt request still busy?
* The host is allowed to skip reading the status,
* so we must cancel it. */
if (fsg->intreq_busy)
usb_ep_dequeue(fsg->intr_in, fsg->intreq);
/* Copy the command and mark the buffer empty */
fsg->data_dir = DATA_DIR_UNKNOWN;
spin_lock_irq(&fsg->lock);
fsg->cmnd_size = fsg->cbbuf_cmnd_size;
memcpy(fsg->cmnd, fsg->cbbuf_cmnd, fsg->cmnd_size);
fsg->cbbuf_cmnd_size = 0;
spin_unlock_irq(&fsg->lock);
}
return rc;
}
/*-------------------------------------------------------------------------*/
static int enable_endpoint(struct fsg_dev *fsg, struct usb_ep *ep,
const struct usb_endpoint_descriptor *d)
{
int rc;
ep->driver_data = fsg;
rc = usb_ep_enable(ep, d);
if (rc)
ERROR(fsg, "can't enable %s, result %d\n", ep->name, rc);
return rc;
}
static int alloc_request(struct fsg_dev *fsg, struct usb_ep *ep,
struct usb_request **preq)
{
*preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
if (*preq)
return 0;
ERROR(fsg, "can't allocate request for %s\n", ep->name);
return -ENOMEM;
}
/*
* Reset interface setting and re-init endpoint state (toggle etc).
* Call with altsetting < 0 to disable the interface. The only other
* available altsetting is 0, which enables the interface.
*/
static int do_set_interface(struct fsg_dev *fsg, int altsetting)
{
int rc = 0;
int i;
const struct usb_endpoint_descriptor *d;
if (fsg->running)
DBG(fsg, "reset interface\n");
reset:
/* Deallocate the requests */
for (i = 0; i < NUM_BUFFERS; ++i) {
struct fsg_buffhd *bh = &fsg->buffhds[i];
if (bh->inreq) {
usb_ep_free_request(fsg->bulk_in, bh->inreq);
bh->inreq = NULL;
}
if (bh->outreq) {
usb_ep_free_request(fsg->bulk_out, bh->outreq);
bh->outreq = NULL;
}
}
if (fsg->intreq) {
usb_ep_free_request(fsg->intr_in, fsg->intreq);
fsg->intreq = NULL;
}
/* Disable the endpoints */
if (fsg->bulk_in_enabled) {
usb_ep_disable(fsg->bulk_in);
fsg->bulk_in_enabled = 0;
}
if (fsg->bulk_out_enabled) {
usb_ep_disable(fsg->bulk_out);
fsg->bulk_out_enabled = 0;
}
if (fsg->intr_in_enabled) {
usb_ep_disable(fsg->intr_in);
fsg->intr_in_enabled = 0;
}
fsg->running = 0;
if (altsetting < 0 || rc != 0)
return rc;
DBG(fsg, "set interface %d\n", altsetting);
/* Enable the endpoints */
d = ep_desc(fsg->gadget, &fs_bulk_in_desc, &hs_bulk_in_desc);
if ((rc = enable_endpoint(fsg, fsg->bulk_in, d)) != 0)
goto reset;
fsg->bulk_in_enabled = 1;
d = ep_desc(fsg->gadget, &fs_bulk_out_desc, &hs_bulk_out_desc);
if ((rc = enable_endpoint(fsg, fsg->bulk_out, d)) != 0)
goto reset;
fsg->bulk_out_enabled = 1;
fsg->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
if (transport_is_cbi()) {
d = ep_desc(fsg->gadget, &fs_intr_in_desc, &hs_intr_in_desc);
if ((rc = enable_endpoint(fsg, fsg->intr_in, d)) != 0)
goto reset;
fsg->intr_in_enabled = 1;
}
/* Allocate the requests */
for (i = 0; i < NUM_BUFFERS; ++i) {
struct fsg_buffhd *bh = &fsg->buffhds[i];
if ((rc = alloc_request(fsg, fsg->bulk_in, &bh->inreq)) != 0)
goto reset;
if ((rc = alloc_request(fsg, fsg->bulk_out, &bh->outreq)) != 0)
goto reset;
bh->inreq->buf = bh->outreq->buf = bh->buf;
bh->inreq->context = bh->outreq->context = bh;
bh->inreq->complete = bulk_in_complete;
bh->outreq->complete = bulk_out_complete;
}
if (transport_is_cbi()) {
if ((rc = alloc_request(fsg, fsg->intr_in, &fsg->intreq)) != 0)
goto reset;
fsg->intreq->complete = intr_in_complete;
}
fsg->running = 1;
for (i = 0; i < fsg->nluns; ++i)
fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED;
return rc;
}
/*
* Change our operational configuration. This code must agree with the code
* that returns config descriptors, and with interface altsetting code.
*
* It's also responsible for power management interactions. Some
* configurations might not work with our current power sources.
* For now we just assume the gadget is always self-powered.
*/
static int do_set_config(struct fsg_dev *fsg, u8 new_config)
{
int rc = 0;
/* Disable the single interface */
if (fsg->config != 0) {
DBG(fsg, "reset config\n");
fsg->config = 0;
rc = do_set_interface(fsg, -1);
}
/* Enable the interface */
if (new_config != 0) {
fsg->config = new_config;
if ((rc = do_set_interface(fsg, 0)) != 0)
fsg->config = 0; // Reset on errors
else {
char *speed;
switch (fsg->gadget->speed) {
case USB_SPEED_LOW: speed = "low"; break;
case USB_SPEED_FULL: speed = "full"; break;
case USB_SPEED_HIGH: speed = "high"; break;
default: speed = "?"; break;
}
INFO(fsg, "%s speed config #%d\n", speed, fsg->config);
}
}
return rc;
}
/*-------------------------------------------------------------------------*/
static void handle_exception(struct fsg_dev *fsg)
{
siginfo_t info;
int sig;
int i;
int num_active;
struct fsg_buffhd *bh;
enum fsg_state old_state;
u8 new_config;
struct lun *curlun;
unsigned int exception_req_tag;
int rc;
/* Clear the existing signals. Anything but SIGUSR1 is converted
* into a high-priority EXIT exception. */
for (;;) {
sig = dequeue_signal_lock(current, &current->blocked, &info);
if (!sig)
break;
if (sig != SIGUSR1) {
if (fsg->state < FSG_STATE_EXIT)
DBG(fsg, "Main thread exiting on signal\n");
raise_exception(fsg, FSG_STATE_EXIT);
}
}
/* Cancel all the pending transfers */
if (fsg->intreq_busy)
usb_ep_dequeue(fsg->intr_in, fsg->intreq);
for (i = 0; i < NUM_BUFFERS; ++i) {
bh = &fsg->buffhds[i];
if (bh->inreq_busy)
usb_ep_dequeue(fsg->bulk_in, bh->inreq);
if (bh->outreq_busy)
usb_ep_dequeue(fsg->bulk_out, bh->outreq);
}
/* Wait until everything is idle */
for (;;) {
num_active = fsg->intreq_busy;
for (i = 0; i < NUM_BUFFERS; ++i) {
bh = &fsg->buffhds[i];
num_active += bh->inreq_busy + bh->outreq_busy;
}
if (num_active == 0)
break;
if (sleep_thread(fsg))
return;
}
/* Clear out the controller's fifos */
if (fsg->bulk_in_enabled)
usb_ep_fifo_flush(fsg->bulk_in);
if (fsg->bulk_out_enabled)
usb_ep_fifo_flush(fsg->bulk_out);
if (fsg->intr_in_enabled)
usb_ep_fifo_flush(fsg->intr_in);
/* Reset the I/O buffer states and pointers, the SCSI
* state, and the exception. Then invoke the handler. */
spin_lock_irq(&fsg->lock);
for (i = 0; i < NUM_BUFFERS; ++i) {
bh = &fsg->buffhds[i];
bh->state = BUF_STATE_EMPTY;
}
fsg->next_buffhd_to_fill = fsg->next_buffhd_to_drain =
&fsg->buffhds[0];
exception_req_tag = fsg->exception_req_tag;
new_config = fsg->new_config;
old_state = fsg->state;
if (old_state == FSG_STATE_ABORT_BULK_OUT)
fsg->state = FSG_STATE_STATUS_PHASE;
else {
for (i = 0; i < fsg->nluns; ++i) {
curlun = &fsg->luns[i];
curlun->prevent_medium_removal = 0;
curlun->sense_data = curlun->unit_attention_data =
SS_NO_SENSE;
curlun->sense_data_info = 0;
curlun->info_valid = 0;
}
fsg->state = FSG_STATE_IDLE;
}
spin_unlock_irq(&fsg->lock);
/* Carry out any extra actions required for the exception */
switch (old_state) {
default:
break;
case FSG_STATE_ABORT_BULK_OUT:
send_status(fsg);
spin_lock_irq(&fsg->lock);
if (fsg->state == FSG_STATE_STATUS_PHASE)
fsg->state = FSG_STATE_IDLE;
spin_unlock_irq(&fsg->lock);
break;
case FSG_STATE_RESET:
/* In case we were forced against our will to halt a
* bulk endpoint, clear the halt now. (The SuperH UDC
* requires this.) */
if (test_and_clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
usb_ep_clear_halt(fsg->bulk_in);
if (transport_is_bbb()) {
if (fsg->ep0_req_tag == exception_req_tag)
ep0_queue(fsg); // Complete the status stage
} else if (transport_is_cbi())
send_status(fsg); // Status by interrupt pipe
/* Technically this should go here, but it would only be
* a waste of time. Ditto for the INTERFACE_CHANGE and
* CONFIG_CHANGE cases. */
// for (i = 0; i < fsg->nluns; ++i)
// fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED;
break;
case FSG_STATE_INTERFACE_CHANGE:
rc = do_set_interface(fsg, 0);
if (fsg->ep0_req_tag != exception_req_tag)
break;
if (rc != 0) // STALL on errors
fsg_set_halt(fsg, fsg->ep0);
else // Complete the status stage
ep0_queue(fsg);
break;
case FSG_STATE_CONFIG_CHANGE:
rc = do_set_config(fsg, new_config);
if (fsg->ep0_req_tag != exception_req_tag)
break;
if (rc != 0) // STALL on errors
fsg_set_halt(fsg, fsg->ep0);
else // Complete the status stage
ep0_queue(fsg);
break;
case FSG_STATE_DISCONNECT:
fsync_all(fsg);
do_set_config(fsg, 0); // Unconfigured state
break;
case FSG_STATE_EXIT:
case FSG_STATE_TERMINATED:
do_set_config(fsg, 0); // Free resources
spin_lock_irq(&fsg->lock);
fsg->state = FSG_STATE_TERMINATED; // Stop the thread
spin_unlock_irq(&fsg->lock);
break;
}
}
/*-------------------------------------------------------------------------*/
static int fsg_main_thread(void *fsg_)
{
struct fsg_dev *fsg = fsg_;
/* Allow the thread to be killed by a signal, but set the signal mask
* to block everything but INT, TERM, KILL, and USR1. */
allow_signal(SIGINT);
allow_signal(SIGTERM);
allow_signal(SIGKILL);
allow_signal(SIGUSR1);
/* Allow the thread to be frozen */
set_freezable();
/* Arrange for userspace references to be interpreted as kernel
* pointers. That way we can pass a kernel pointer to a routine
* that expects a __user pointer and it will work okay. */
set_fs(get_ds());
/* The main loop */
while (fsg->state != FSG_STATE_TERMINATED) {
if (exception_in_progress(fsg) || signal_pending(current)) {
handle_exception(fsg);
continue;
}
if (!fsg->running) {
sleep_thread(fsg);
continue;
}
if (get_next_command(fsg))
continue;
spin_lock_irq(&fsg->lock);
if (!exception_in_progress(fsg))
fsg->state = FSG_STATE_DATA_PHASE;
spin_unlock_irq(&fsg->lock);
if (do_scsi_command(fsg) || finish_reply(fsg))
continue;
spin_lock_irq(&fsg->lock);
if (!exception_in_progress(fsg))
fsg->state = FSG_STATE_STATUS_PHASE;
spin_unlock_irq(&fsg->lock);
if (send_status(fsg))
continue;
spin_lock_irq(&fsg->lock);
if (!exception_in_progress(fsg))
fsg->state = FSG_STATE_IDLE;
spin_unlock_irq(&fsg->lock);
}
spin_lock_irq(&fsg->lock);
fsg->thread_task = NULL;
spin_unlock_irq(&fsg->lock);
/* If we are exiting because of a signal, unregister the
* gadget driver. */
if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags))
usb_gadget_unregister_driver(&fsg_driver);
/* Let the unbind and cleanup routines know the thread has exited */
complete_and_exit(&fsg->thread_notifier, 0);
}
/*-------------------------------------------------------------------------*/
/* If the next two routines are called while the gadget is registered,
* the caller must own fsg->filesem for writing. */
static int open_backing_file(struct lun *curlun, const char *filename)
{
int ro;
struct file *filp = NULL;
int rc = -EINVAL;
struct inode *inode = NULL;
loff_t size;
loff_t num_sectors;
loff_t min_sectors;
/* R/W if we can, R/O if we must */
ro = curlun->ro;
if (!ro) {
filp = filp_open(filename, O_RDWR | O_LARGEFILE, 0);
if (-EROFS == PTR_ERR(filp))
ro = 1;
}
if (ro)
filp = filp_open(filename, O_RDONLY | O_LARGEFILE, 0);
if (IS_ERR(filp)) {
LINFO(curlun, "unable to open backing file: %s\n", filename);
return PTR_ERR(filp);
}
if (!(filp->f_mode & FMODE_WRITE))
ro = 1;
if (filp->f_path.dentry)
inode = filp->f_path.dentry->d_inode;
if (inode && S_ISBLK(inode->i_mode)) {
if (bdev_read_only(inode->i_bdev))
ro = 1;
} else if (!inode || !S_ISREG(inode->i_mode)) {
LINFO(curlun, "invalid file type: %s\n", filename);
goto out;
}
/* If we can't read the file, it's no good.
* If we can't write the file, use it read-only. */
if (!filp->f_op || !(filp->f_op->read || filp->f_op->aio_read)) {
LINFO(curlun, "file not readable: %s\n", filename);
goto out;
}
if (!(filp->f_op->write || filp->f_op->aio_write))
ro = 1;
size = i_size_read(inode->i_mapping->host);
if (size < 0) {
LINFO(curlun, "unable to find file size: %s\n", filename);
rc = (int) size;
goto out;
}
num_sectors = size >> 9; // File size in 512-byte blocks
min_sectors = 1;
if (mod_data.cdrom) {
num_sectors &= ~3; // Reduce to a multiple of 2048
min_sectors = 300*4; // Smallest track is 300 frames
if (num_sectors >= 256*60*75*4) {
num_sectors = (256*60*75 - 1) * 4;
LINFO(curlun, "file too big: %s\n", filename);
LINFO(curlun, "using only first %d blocks\n",
(int) num_sectors);
}
}
if (num_sectors < min_sectors) {
LINFO(curlun, "file too small: %s\n", filename);
rc = -ETOOSMALL;
goto out;
}
get_file(filp);
curlun->ro = ro;
curlun->filp = filp;
curlun->file_length = size;
curlun->num_sectors = num_sectors;
LDBG(curlun, "open backing file: %s\n", filename);
rc = 0;
out:
filp_close(filp, current->files);
return rc;
}
static void close_backing_file(struct lun *curlun)
{
if (curlun->filp) {
LDBG(curlun, "close backing file\n");
fput(curlun->filp);
curlun->filp = NULL;
}
}
static ssize_t show_ro(struct device *dev, struct device_attribute *attr, char *buf)
{
struct lun *curlun = dev_to_lun(dev);
return sprintf(buf, "%d\n", curlun->ro);
}
static ssize_t show_file(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct lun *curlun = dev_to_lun(dev);
struct fsg_dev *fsg = dev_get_drvdata(dev);
char *p;
ssize_t rc;
down_read(&fsg->filesem);
if (backing_file_is_open(curlun)) { // Get the complete pathname
p = d_path(&curlun->filp->f_path, buf, PAGE_SIZE - 1);
if (IS_ERR(p))
rc = PTR_ERR(p);
else {
rc = strlen(p);
memmove(buf, p, rc);
buf[rc] = '\n'; // Add a newline
buf[++rc] = 0;
}
} else { // No file, return 0 bytes
*buf = 0;
rc = 0;
}
up_read(&fsg->filesem);
return rc;
}
static ssize_t store_ro(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
ssize_t rc = count;
struct lun *curlun = dev_to_lun(dev);
struct fsg_dev *fsg = dev_get_drvdata(dev);
int i;
if (sscanf(buf, "%d", &i) != 1)
return -EINVAL;
/* Allow the write-enable status to change only while the backing file
* is closed. */
down_read(&fsg->filesem);
if (backing_file_is_open(curlun)) {
LDBG(curlun, "read-only status change prevented\n");
rc = -EBUSY;
} else {
curlun->ro = !!i;
LDBG(curlun, "read-only status set to %d\n", curlun->ro);
}
up_read(&fsg->filesem);
return rc;
}
static ssize_t store_file(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct lun *curlun = dev_to_lun(dev);
struct fsg_dev *fsg = dev_get_drvdata(dev);
int rc = 0;
if (curlun->prevent_medium_removal && backing_file_is_open(curlun)) {
LDBG(curlun, "eject attempt prevented\n");
return -EBUSY; // "Door is locked"
}
/* Remove a trailing newline */
if (count > 0 && buf[count-1] == '\n')
((char *) buf)[count-1] = 0; // Ugh!
/* Eject current medium */
down_write(&fsg->filesem);
if (backing_file_is_open(curlun)) {
close_backing_file(curlun);
curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
}
/* Load new medium */
if (count > 0 && buf[0]) {
rc = open_backing_file(curlun, buf);
if (rc == 0)
curlun->unit_attention_data =
SS_NOT_READY_TO_READY_TRANSITION;
}
up_write(&fsg->filesem);
return (rc < 0 ? rc : count);
}
/* The write permissions and store_xxx pointers are set in fsg_bind() */
static DEVICE_ATTR(ro, 0444, show_ro, NULL);
static DEVICE_ATTR(file, 0444, show_file, NULL);
/*-------------------------------------------------------------------------*/
static void fsg_release(struct kref *ref)
{
struct fsg_dev *fsg = container_of(ref, struct fsg_dev, ref);
kfree(fsg->luns);
kfree(fsg);
}
static void lun_release(struct device *dev)
{
struct fsg_dev *fsg = dev_get_drvdata(dev);
kref_put(&fsg->ref, fsg_release);
}
static void /* __init_or_exit */ fsg_unbind(struct usb_gadget *gadget)
{
struct fsg_dev *fsg = get_gadget_data(gadget);
int i;
struct lun *curlun;
struct usb_request *req = fsg->ep0req;
DBG(fsg, "unbind\n");
clear_bit(REGISTERED, &fsg->atomic_bitflags);
/* Unregister the sysfs attribute files and the LUNs */
for (i = 0; i < fsg->nluns; ++i) {
curlun = &fsg->luns[i];
if (curlun->registered) {
device_remove_file(&curlun->dev, &dev_attr_ro);
device_remove_file(&curlun->dev, &dev_attr_file);
close_backing_file(curlun);
device_unregister(&curlun->dev);
curlun->registered = 0;
}
}
/* If the thread isn't already dead, tell it to exit now */
if (fsg->state != FSG_STATE_TERMINATED) {
raise_exception(fsg, FSG_STATE_EXIT);
wait_for_completion(&fsg->thread_notifier);
/* The cleanup routine waits for this completion also */
complete(&fsg->thread_notifier);
}
/* Free the data buffers */
for (i = 0; i < NUM_BUFFERS; ++i)
kfree(fsg->buffhds[i].buf);
/* Free the request and buffer for endpoint 0 */
if (req) {
kfree(req->buf);
usb_ep_free_request(fsg->ep0, req);
}
set_gadget_data(gadget, NULL);
}
static int __init check_parameters(struct fsg_dev *fsg)
{
int prot;
int gcnum;
/* Store the default values */
mod_data.transport_type = USB_PR_BULK;
mod_data.transport_name = "Bulk-only";
mod_data.protocol_type = USB_SC_SCSI;
mod_data.protocol_name = "Transparent SCSI";
/* Some peripheral controllers are known not to be able to
* halt bulk endpoints correctly. If one of them is present,
* disable stalls.
*/
if (gadget_is_sh(fsg->gadget) || gadget_is_at91(fsg->gadget))
mod_data.can_stall = 0;
if (mod_data.release == 0xffff) { // Parameter wasn't set
/* The sa1100 controller is not supported */
if (gadget_is_sa1100(fsg->gadget))
gcnum = -1;
else
gcnum = usb_gadget_controller_number(fsg->gadget);
if (gcnum >= 0)
mod_data.release = 0x0300 + gcnum;
else {
WARNING(fsg, "controller '%s' not recognized\n",
fsg->gadget->name);
mod_data.release = 0x0399;
}
}
prot = simple_strtol(mod_data.protocol_parm, NULL, 0);
#ifdef CONFIG_USB_FILE_STORAGE_TEST
if (strnicmp(mod_data.transport_parm, "BBB", 10) == 0) {
; // Use default setting
} else if (strnicmp(mod_data.transport_parm, "CB", 10) == 0) {
mod_data.transport_type = USB_PR_CB;
mod_data.transport_name = "Control-Bulk";
} else if (strnicmp(mod_data.transport_parm, "CBI", 10) == 0) {
mod_data.transport_type = USB_PR_CBI;
mod_data.transport_name = "Control-Bulk-Interrupt";
} else {
ERROR(fsg, "invalid transport: %s\n", mod_data.transport_parm);
return -EINVAL;
}
if (strnicmp(mod_data.protocol_parm, "SCSI", 10) == 0 ||
prot == USB_SC_SCSI) {
; // Use default setting
} else if (strnicmp(mod_data.protocol_parm, "RBC", 10) == 0 ||
prot == USB_SC_RBC) {
mod_data.protocol_type = USB_SC_RBC;
mod_data.protocol_name = "RBC";
} else if (strnicmp(mod_data.protocol_parm, "8020", 4) == 0 ||
strnicmp(mod_data.protocol_parm, "ATAPI", 10) == 0 ||
prot == USB_SC_8020) {
mod_data.protocol_type = USB_SC_8020;
mod_data.protocol_name = "8020i (ATAPI)";
} else if (strnicmp(mod_data.protocol_parm, "QIC", 3) == 0 ||
prot == USB_SC_QIC) {
mod_data.protocol_type = USB_SC_QIC;
mod_data.protocol_name = "QIC-157";
} else if (strnicmp(mod_data.protocol_parm, "UFI", 10) == 0 ||
prot == USB_SC_UFI) {
mod_data.protocol_type = USB_SC_UFI;
mod_data.protocol_name = "UFI";
} else if (strnicmp(mod_data.protocol_parm, "8070", 4) == 0 ||
prot == USB_SC_8070) {
mod_data.protocol_type = USB_SC_8070;
mod_data.protocol_name = "8070i";
} else {
ERROR(fsg, "invalid protocol: %s\n", mod_data.protocol_parm);
return -EINVAL;
}
mod_data.buflen &= PAGE_CACHE_MASK;
if (mod_data.buflen <= 0) {
ERROR(fsg, "invalid buflen\n");
return -ETOOSMALL;
}
#endif /* CONFIG_USB_FILE_STORAGE_TEST */
return 0;
}
static int __init fsg_bind(struct usb_gadget *gadget)
{
struct fsg_dev *fsg = the_fsg;
int rc;
int i;
struct lun *curlun;
struct usb_ep *ep;
struct usb_request *req;
char *pathbuf, *p;
fsg->gadget = gadget;
set_gadget_data(gadget, fsg);
fsg->ep0 = gadget->ep0;
fsg->ep0->driver_data = fsg;
if ((rc = check_parameters(fsg)) != 0)
goto out;
if (mod_data.removable) { // Enable the store_xxx attributes
dev_attr_file.attr.mode = 0644;
dev_attr_file.store = store_file;
if (!mod_data.cdrom) {
dev_attr_ro.attr.mode = 0644;
dev_attr_ro.store = store_ro;
}
}
/* Find out how many LUNs there should be */
i = mod_data.nluns;
if (i == 0)
i = max(mod_data.num_filenames, 1u);
if (i > MAX_LUNS) {
ERROR(fsg, "invalid number of LUNs: %d\n", i);
rc = -EINVAL;
goto out;
}
/* Create the LUNs, open their backing files, and register the
* LUN devices in sysfs. */
fsg->luns = kzalloc(i * sizeof(struct lun), GFP_KERNEL);
if (!fsg->luns) {
rc = -ENOMEM;
goto out;
}
fsg->nluns = i;
for (i = 0; i < fsg->nluns; ++i) {
curlun = &fsg->luns[i];
curlun->ro = mod_data.ro[i];
if (mod_data.cdrom)
curlun->ro = 1;
curlun->dev.release = lun_release;
curlun->dev.parent = &gadget->dev;
curlun->dev.driver = &fsg_driver.driver;
dev_set_drvdata(&curlun->dev, fsg);
dev_set_name(&curlun->dev,"%s-lun%d",
dev_name(&gadget->dev), i);
if ((rc = device_register(&curlun->dev)) != 0) {
INFO(fsg, "failed to register LUN%d: %d\n", i, rc);
goto out;
}
if ((rc = device_create_file(&curlun->dev,
&dev_attr_ro)) != 0 ||
(rc = device_create_file(&curlun->dev,
&dev_attr_file)) != 0) {
device_unregister(&curlun->dev);
goto out;
}
curlun->registered = 1;
kref_get(&fsg->ref);
if (mod_data.file[i] && *mod_data.file[i]) {
if ((rc = open_backing_file(curlun,
mod_data.file[i])) != 0)
goto out;
} else if (!mod_data.removable) {
ERROR(fsg, "no file given for LUN%d\n", i);
rc = -EINVAL;
goto out;
}
}
/* Find all the endpoints we will use */
usb_ep_autoconfig_reset(gadget);
ep = usb_ep_autoconfig(gadget, &fs_bulk_in_desc);
if (!ep)
goto autoconf_fail;
ep->driver_data = fsg; // claim the endpoint
fsg->bulk_in = ep;
ep = usb_ep_autoconfig(gadget, &fs_bulk_out_desc);
if (!ep)
goto autoconf_fail;
ep->driver_data = fsg; // claim the endpoint
fsg->bulk_out = ep;
if (transport_is_cbi()) {
ep = usb_ep_autoconfig(gadget, &fs_intr_in_desc);
if (!ep)
goto autoconf_fail;
ep->driver_data = fsg; // claim the endpoint
fsg->intr_in = ep;
}
/* Fix up the descriptors */
device_desc.bMaxPacketSize0 = fsg->ep0->maxpacket;
device_desc.idVendor = cpu_to_le16(mod_data.vendor);
device_desc.idProduct = cpu_to_le16(mod_data.product);
device_desc.bcdDevice = cpu_to_le16(mod_data.release);
i = (transport_is_cbi() ? 3 : 2); // Number of endpoints
intf_desc.bNumEndpoints = i;
intf_desc.bInterfaceSubClass = mod_data.protocol_type;
intf_desc.bInterfaceProtocol = mod_data.transport_type;
fs_function[i + FS_FUNCTION_PRE_EP_ENTRIES] = NULL;
if (gadget_is_dualspeed(gadget)) {
hs_function[i + HS_FUNCTION_PRE_EP_ENTRIES] = NULL;
/* Assume ep0 uses the same maxpacket value for both speeds */
dev_qualifier.bMaxPacketSize0 = fsg->ep0->maxpacket;
/* Assume endpoint addresses are the same for both speeds */
hs_bulk_in_desc.bEndpointAddress =
fs_bulk_in_desc.bEndpointAddress;
hs_bulk_out_desc.bEndpointAddress =
fs_bulk_out_desc.bEndpointAddress;
hs_intr_in_desc.bEndpointAddress =
fs_intr_in_desc.bEndpointAddress;
}
if (gadget_is_otg(gadget))
otg_desc.bmAttributes |= USB_OTG_HNP;
rc = -ENOMEM;
/* Allocate the request and buffer for endpoint 0 */
fsg->ep0req = req = usb_ep_alloc_request(fsg->ep0, GFP_KERNEL);
if (!req)
goto out;
req->buf = kmalloc(EP0_BUFSIZE, GFP_KERNEL);
if (!req->buf)
goto out;
req->complete = ep0_complete;
/* Allocate the data buffers */
for (i = 0; i < NUM_BUFFERS; ++i) {
struct fsg_buffhd *bh = &fsg->buffhds[i];
/* Allocate for the bulk-in endpoint. We assume that
* the buffer will also work with the bulk-out (and
* interrupt-in) endpoint. */
bh->buf = kmalloc(mod_data.buflen, GFP_KERNEL);
if (!bh->buf)
goto out;
bh->next = bh + 1;
}
fsg->buffhds[NUM_BUFFERS - 1].next = &fsg->buffhds[0];
/* This should reflect the actual gadget power source */
usb_gadget_set_selfpowered(gadget);
snprintf(manufacturer, sizeof manufacturer, "%s %s with %s",
init_utsname()->sysname, init_utsname()->release,
gadget->name);
/* On a real device, serial[] would be loaded from permanent
* storage. We just encode it from the driver version string. */
for (i = 0; i < sizeof(serial) - 2; i += 2) {
unsigned char c = DRIVER_VERSION[i / 2];
if (!c)
break;
sprintf(&serial[i], "%02X", c);
}
fsg->thread_task = kthread_create(fsg_main_thread, fsg,
"file-storage-gadget");
if (IS_ERR(fsg->thread_task)) {
rc = PTR_ERR(fsg->thread_task);
goto out;
}
INFO(fsg, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
INFO(fsg, "Number of LUNs=%d\n", fsg->nluns);
pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
for (i = 0; i < fsg->nluns; ++i) {
curlun = &fsg->luns[i];
if (backing_file_is_open(curlun)) {
p = NULL;
if (pathbuf) {
p = d_path(&curlun->filp->f_path,
pathbuf, PATH_MAX);
if (IS_ERR(p))
p = NULL;
}
LINFO(curlun, "ro=%d, file: %s\n",
curlun->ro, (p ? p : "(error)"));
}
}
kfree(pathbuf);
DBG(fsg, "transport=%s (x%02x)\n",
mod_data.transport_name, mod_data.transport_type);
DBG(fsg, "protocol=%s (x%02x)\n",
mod_data.protocol_name, mod_data.protocol_type);
DBG(fsg, "VendorID=x%04x, ProductID=x%04x, Release=x%04x\n",
mod_data.vendor, mod_data.product, mod_data.release);
DBG(fsg, "removable=%d, stall=%d, cdrom=%d, buflen=%u\n",
mod_data.removable, mod_data.can_stall,
mod_data.cdrom, mod_data.buflen);
DBG(fsg, "I/O thread pid: %d\n", task_pid_nr(fsg->thread_task));
set_bit(REGISTERED, &fsg->atomic_bitflags);
/* Tell the thread to start working */
wake_up_process(fsg->thread_task);
return 0;
autoconf_fail:
ERROR(fsg, "unable to autoconfigure all endpoints\n");
rc = -ENOTSUPP;
out:
fsg->state = FSG_STATE_TERMINATED; // The thread is dead
fsg_unbind(gadget);
complete(&fsg->thread_notifier);
return rc;
}
/*-------------------------------------------------------------------------*/
static void fsg_suspend(struct usb_gadget *gadget)
{
struct fsg_dev *fsg = get_gadget_data(gadget);
DBG(fsg, "suspend\n");
set_bit(SUSPENDED, &fsg->atomic_bitflags);
}
static void fsg_resume(struct usb_gadget *gadget)
{
struct fsg_dev *fsg = get_gadget_data(gadget);
DBG(fsg, "resume\n");
clear_bit(SUSPENDED, &fsg->atomic_bitflags);
}
/*-------------------------------------------------------------------------*/
static struct usb_gadget_driver fsg_driver = {
#ifdef CONFIG_USB_GADGET_DUALSPEED
.speed = USB_SPEED_HIGH,
#else
.speed = USB_SPEED_FULL,
#endif
.function = (char *) longname,
.bind = fsg_bind,
.unbind = fsg_unbind,
.disconnect = fsg_disconnect,
.setup = fsg_setup,
.suspend = fsg_suspend,
.resume = fsg_resume,
.driver = {
.name = (char *) shortname,
.owner = THIS_MODULE,
// .release = ...
// .suspend = ...
// .resume = ...
},
};
static int __init fsg_alloc(void)
{
struct fsg_dev *fsg;
fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
if (!fsg)
return -ENOMEM;
spin_lock_init(&fsg->lock);
init_rwsem(&fsg->filesem);
kref_init(&fsg->ref);
init_completion(&fsg->thread_notifier);
the_fsg = fsg;
return 0;
}
static int __init fsg_init(void)
{
int rc;
struct fsg_dev *fsg;
if ((rc = fsg_alloc()) != 0)
return rc;
fsg = the_fsg;
if ((rc = usb_gadget_register_driver(&fsg_driver)) != 0)
kref_put(&fsg->ref, fsg_release);
return rc;
}
module_init(fsg_init);
static void __exit fsg_cleanup(void)
{
struct fsg_dev *fsg = the_fsg;
/* Unregister the driver iff the thread hasn't already done so */
if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags))
usb_gadget_unregister_driver(&fsg_driver);
/* Wait for the thread to finish up */
wait_for_completion(&fsg->thread_notifier);
kref_put(&fsg->ref, fsg_release);
}
module_exit(fsg_cleanup);
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