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linux_dsm_epyc7002/drivers/usb/gadget/file_storage.c
Maxin B John 849426c3a4 usb: gadget: Remove the LUN checks which are always true 
Comparing an unsigned integer with greater than or equal to zero is
always true.  So, it is safe to remove similar checks from
'f_mass_storage.c' and 'file_storage.c'

Signed-off-by: Maxin B. John <maxin.john@gmail.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-05-10 14:14:59 -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, release number and serial 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
* serial=HHHH... Required serial number (string of hex chars)
* 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
* nofua=b[,b...] Default false, booleans for ignore FUA flag
* in SCSI WRITE(10,12) commands
* 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", "serial", "ro",
* "removable", "luns", "nofua", "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", "nofua", 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 "1 September 2010"
static char fsg_string_manufacturer[64];
static const char fsg_string_product[] = DRIVER_DESC;
static const char fsg_string_config[] = "Self-powered";
static const char fsg_string_interface[] = "Mass Storage";
#include "storage_common.c"
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Alan Stern");
MODULE_LICENSE("Dual BSD/GPL");
/*
* 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.
*/
/*-------------------------------------------------------------------------*/
/* Encapsulate the module parameter settings */
static struct {
char *file[FSG_MAX_LUNS];
char *serial;
int ro[FSG_MAX_LUNS];
int nofua[FSG_MAX_LUNS];
unsigned int num_filenames;
unsigned int num_ros;
unsigned int num_nofuas;
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 = FSG_VENDOR_ID,
.product = FSG_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_named(serial, mod_data.serial, charp, S_IRUGO);
MODULE_PARM_DESC(serial, "USB serial number");
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_array_named(nofua, mod_data.nofua, bool, &mod_data.num_nofuas,
S_IRUGO);
MODULE_PARM_DESC(nofua, "true to ignore SCSI WRITE(10,12) FUA bit");
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 */
/*
* 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 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[FSG_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 fsg_lun *luns;
struct fsg_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 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);
}
/*-------------------------------------------------------------------------*/
/*
* 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().
*/
/* 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(FSG_VENDOR_ID),
.idProduct = cpu_to_le16(FSG_PRODUCT_ID),
.bcdDevice = cpu_to_le16(0xffff),
.iManufacturer = FSG_STRING_MANUFACTURER,
.iProduct = FSG_STRING_PRODUCT,
.iSerialNumber = FSG_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 = FSG_STRING_CONFIG,
.bmAttributes = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
.bMaxPower = CONFIG_USB_GADGET_VBUS_DRAW / 2,
};
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,
};
/*
* 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;
function = gadget_is_dualspeed(gadget) && speed == USB_SPEED_HIGH
? (const struct usb_descriptor_header **)fsg_hs_function
: (const struct usb_descriptor_header **)fsg_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] = {
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(&fsg_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 fsg_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] == READ_6)
lba = get_unaligned_be24(&fsg->cmnd[1]);
else {
lba = get_unaligned_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 fsg_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] == WRITE_6)
lba = get_unaligned_be24(&fsg->cmnd[1]);
else {
lba = get_unaligned_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;
}
/* FUA */
if (!curlun->nofua && (fsg->cmnd[1] & 0x08)) {
spin_lock(&curlun->filp->f_lock);
curlun->filp->f_flags |= O_DSYNC;
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
}
/*-------------------------------------------------------------------------*/
static int do_synchronize_cache(struct fsg_dev *fsg)
{
struct fsg_lun *curlun = fsg->curlun;
int rc;
/* We ignore the requested LBA and write out all file's
* dirty data buffers. */
rc = fsg_lun_fsync_sub(curlun);
if (rc)
curlun->sense_data = SS_WRITE_ERROR;
return 0;
}
/*-------------------------------------------------------------------------*/
static void invalidate_sub(struct fsg_lun *curlun)
{
struct file *filp = curlun->filp;
struct inode *inode = filp->f_path.dentry->d_inode;
unsigned long rc;
rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
}
static int do_verify(struct fsg_dev *fsg)
{
struct fsg_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_unaligned_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_unaligned_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 */
fsg_lun_fsync_sub(curlun);
if (signal_pending(current))
return -EINTR;
invalidate_sub(curlun);
if (signal_pending(current))
return -EINTR;
/* Just try to read the requested blocks */
while (amount_left > 0) {
/* Figure out how much we need to read:
* Try to read the remaining amount, but not more than
* the buffer size.
* And don't try to read past the end of the file.
* If this means reading 0 then we were asked to read
* past the end of file. */
amount = min((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_ROM : 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 fsg_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_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
buf[7] = 18 - 8; // Additional sense length
buf[12] = ASC(sd);
buf[13] = ASCQ(sd);
return 18;
}
static int do_read_capacity(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{
struct fsg_lun *curlun = fsg->curlun;
u32 lba = get_unaligned_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_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
/* Max logical block */
put_unaligned_be32(512, &buf[4]); /* Block length */
return 8;
}
static int do_read_header(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{
struct fsg_lun *curlun = fsg->curlun;
int msf = fsg->cmnd[1] & 0x02;
u32 lba = get_unaligned_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 fsg_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 fsg_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 == MODE_SENSE) {
buf[2] = (curlun->ro ? 0x80 : 0x00); // WP, DPOFUA
buf += 4;
limit = 255;
} else { // MODE_SENSE_10
buf[3] = (curlun->ro ? 0x80 : 0x00); // WP, DPOFUA
buf += 8;
limit = 65535; // Should really be 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_unaligned_be16(0xffff, &buf[4]);
/* Don't disable prefetch */
/* Minimum prefetch = 0 */
put_unaligned_be16(0xffff, &buf[8]);
/* Maximum prefetch */
put_unaligned_be16(0xffff, &buf[10]);
/* Maximum prefetch ceiling */
}
buf += 12;
}
/* Check that a valid page was requested and the mode data length
* isn't too long. */
len = buf - buf0;
if (!valid_page || len > limit) {
curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
return -EINVAL;
}
/* Store the mode data length */
if (mscmnd == MODE_SENSE)
buf0[0] = len - 1;
else
put_unaligned_be16(len - 2, buf0);
return len;
}
static int do_start_stop(struct fsg_dev *fsg)
{
struct fsg_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);
fsg_lun_close(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 (!fsg_lun_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 fsg_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)
fsg_lun_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 fsg_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_unaligned_be32(curlun->num_sectors, &buf[0]);
/* Number of blocks */
put_unaligned_be32(512, &buf[4]); /* Block length */
buf[4] = 0x02; /* Current capacity */
return 12;
}
static int do_mode_select(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{
struct fsg_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 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, mark the end of the data with a short
* packet. If we are allowed to stall, halt the bulk-in
* endpoint. (Note: This violates the Bulk-Only Transport
* specification, which requires us to pad the data if we
* don't halt the endpoint. Presumably nobody will mind.)
*/
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;
if (mod_data.can_stall)
rc = halt_bulk_in_endpoint(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 fsg_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 fsg_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 < fsg->nluns) {
fsg->curlun = curlun = &fsg->luns[fsg->lun];
if (fsg->cmnd[0] != 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] != INQUIRY &&
fsg->cmnd[0] != 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] != INQUIRY &&
fsg->cmnd[0] != 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 && !fsg_lun_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 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 MODE_SELECT:
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 MODE_SELECT_10:
fsg->data_size_from_cmnd = get_unaligned_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 MODE_SENSE:
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 MODE_SENSE_10:
fsg->data_size_from_cmnd = get_unaligned_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 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 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 READ_10:
fsg->data_size_from_cmnd =
get_unaligned_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 READ_12:
fsg->data_size_from_cmnd =
get_unaligned_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 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 READ_HEADER:
if (!mod_data.cdrom)
goto unknown_cmnd;
fsg->data_size_from_cmnd = get_unaligned_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 READ_TOC:
if (!mod_data.cdrom)
goto unknown_cmnd;
fsg->data_size_from_cmnd = get_unaligned_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 READ_FORMAT_CAPACITIES:
fsg->data_size_from_cmnd = get_unaligned_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 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 START_STOP:
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 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 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 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 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 WRITE_10:
fsg->data_size_from_cmnd =
get_unaligned_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 WRITE_12:
fsg->data_size_from_cmnd =
get_unaligned_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 FORMAT_UNIT:
case RELEASE:
case RESERVE:
case 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 fsg_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 >= FSG_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 < FSG_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 = fsg_ep_desc(fsg->gadget,
&fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
if ((rc = enable_endpoint(fsg, fsg->bulk_in, d)) != 0)
goto reset;
fsg->bulk_in_enabled = 1;
d = fsg_ep_desc(fsg->gadget,
&fsg_fs_bulk_out_desc, &fsg_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 = fsg_ep_desc(fsg->gadget,
&fsg_fs_intr_in_desc, &fsg_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 < FSG_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 fsg_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 < FSG_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 < FSG_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 < FSG_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:
for (i = 0; i < fsg->nluns; ++i)
fsg_lun_fsync_sub(fsg->luns + i);
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);
}
/*-------------------------------------------------------------------------*/
/* The write permissions and store_xxx pointers are set in fsg_bind() */
static DEVICE_ATTR(ro, 0444, fsg_show_ro, NULL);
static DEVICE_ATTR(nofua, 0644, fsg_show_nofua, NULL);
static DEVICE_ATTR(file, 0444, fsg_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 rw_semaphore *filesem = dev_get_drvdata(dev);
struct fsg_dev *fsg =
container_of(filesem, struct fsg_dev, filesem);
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 fsg_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_nofua);
device_remove_file(&curlun->dev, &dev_attr_ro);
device_remove_file(&curlun->dev, &dev_attr_file);
fsg_lun_close(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 < FSG_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_at91(fsg->gadget))
mod_data.can_stall = 0;
if (mod_data.release == 0xffff) { // Parameter wasn't set
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 */
/* Serial string handling.
* On a real device, the serial string would be loaded
* from permanent storage. */
if (mod_data.serial) {
const char *ch;
unsigned len = 0;
/* Sanity check :
* The CB[I] specification limits the serial string to
* 12 uppercase hexadecimal characters.
* BBB need at least 12 uppercase hexadecimal characters,
* with a maximum of 126. */
for (ch = mod_data.serial; *ch; ++ch) {
++len;
if ((*ch < '0' || *ch > '9') &&
(*ch < 'A' || *ch > 'F')) { /* not uppercase hex */
WARNING(fsg,
"Invalid serial string character: %c\n",
*ch);
goto no_serial;
}
}
if (len > 126 ||
(mod_data.transport_type == USB_PR_BULK && len < 12) ||
(mod_data.transport_type != USB_PR_BULK && len > 12)) {
WARNING(fsg, "Invalid serial string length!\n");
goto no_serial;
}
fsg_strings[FSG_STRING_SERIAL - 1].s = mod_data.serial;
} else {
WARNING(fsg, "No serial-number string provided!\n");
no_serial:
device_desc.iSerialNumber = 0;
}
return 0;
}
static int __init fsg_bind(struct usb_gadget *gadget)
{
struct fsg_dev *fsg = the_fsg;
int rc;
int i;
struct fsg_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 = fsg_store_file;
if (!mod_data.cdrom) {
dev_attr_ro.attr.mode = 0644;
dev_attr_ro.store = fsg_store_ro;
}
}
/* Only for removable media? */
dev_attr_nofua.attr.mode = 0644;
dev_attr_nofua.store = fsg_store_nofua;
/* Find out how many LUNs there should be */
i = mod_data.nluns;
if (i == 0)
i = max(mod_data.num_filenames, 1u);
if (i > FSG_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 fsg_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->cdrom = !!mod_data.cdrom;
curlun->ro = mod_data.cdrom || mod_data.ro[i];
curlun->initially_ro = curlun->ro;
curlun->removable = mod_data.removable;
curlun->nofua = mod_data.nofua[i];
curlun->dev.release = lun_release;
curlun->dev.parent = &gadget->dev;
curlun->dev.driver = &fsg_driver.driver;
dev_set_drvdata(&curlun->dev, &fsg->filesem);
dev_set_name(&curlun->dev,"%s-lun%d",
dev_name(&gadget->dev), i);
kref_get(&fsg->ref);
rc = device_register(&curlun->dev);
if (rc) {
INFO(fsg, "failed to register LUN%d: %d\n", i, rc);
put_device(&curlun->dev);
goto out;
}
curlun->registered = 1;
rc = device_create_file(&curlun->dev, &dev_attr_ro);
if (rc)
goto out;
rc = device_create_file(&curlun->dev, &dev_attr_nofua);
if (rc)
goto out;
rc = device_create_file(&curlun->dev, &dev_attr_file);
if (rc)
goto out;
if (mod_data.file[i] && *mod_data.file[i]) {
rc = fsg_lun_open(curlun, mod_data.file[i]);
if (rc)
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, &fsg_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, &fsg_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, &fsg_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
fsg_intf_desc.bNumEndpoints = i;
fsg_intf_desc.bInterfaceSubClass = mod_data.protocol_type;
fsg_intf_desc.bInterfaceProtocol = mod_data.transport_type;
fsg_fs_function[i + FSG_FS_FUNCTION_PRE_EP_ENTRIES] = NULL;
if (gadget_is_dualspeed(gadget)) {
fsg_hs_function[i + FSG_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 */
fsg_hs_bulk_in_desc.bEndpointAddress =
fsg_fs_bulk_in_desc.bEndpointAddress;
fsg_hs_bulk_out_desc.bEndpointAddress =
fsg_fs_bulk_out_desc.bEndpointAddress;
fsg_hs_intr_in_desc.bEndpointAddress =
fsg_fs_intr_in_desc.bEndpointAddress;
}
if (gadget_is_otg(gadget))
fsg_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 < FSG_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[FSG_NUM_BUFFERS - 1].next = &fsg->buffhds[0];
/* This should reflect the actual gadget power source */
usb_gadget_set_selfpowered(gadget);
snprintf(fsg_string_manufacturer, sizeof fsg_string_manufacturer,
"%s %s with %s",
init_utsname()->sysname, init_utsname()->release,
gadget->name);
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 (fsg_lun_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, nofua=%d, file: %s\n",
curlun->ro, curlun->nofua, (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 *) fsg_string_product,
.unbind = fsg_unbind,
.disconnect = fsg_disconnect,
.setup = fsg_setup,
.suspend = fsg_suspend,
.resume = fsg_resume,
.driver = {
.name = DRIVER_NAME,
.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_probe_driver(&fsg_driver, fsg_bind)) != 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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