From: Ahmad Fatoum <a.fatoum@pengutronix.de>
To: Ahmad Fatoum <a.fatoum@pengutronix.de>,
"barebox@lists.infradead.org" <barebox@lists.infradead.org>
Subject: Re: [PATCH 3/3] usbgadget: add support for USB mass storage gadget
Date: Wed, 17 Feb 2021 12:48:39 +0100 [thread overview]
Message-ID: <508b4ab2-3f0b-2f34-e5bc-61141b307304@pengutronix.de> (raw)
In-Reply-To: <20210215102740.30418-4-a.fatoum@pengutronix.de>
On 15.02.21 11:27, Ahmad Fatoum wrote:
> This driver is based on the f_mass_storage drivers in Linux v5.11 and
> U-Boot v2021.01. Like with U-Boot, it's invoked with a blocking ums
> command. During this time, no other processing, except for pollers, is
> possible. The command can be aborted with ctrl+c.
>
> The state machine to implement the mass storage gadget is quite
> extensive, so import the functionality now and delay moving the state
> machine into a poller for asynchronous operation as part of a composite
> gadget for later.
I noticed some brokenness in handling error condition.
I'll respin later this week.
>
> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> ---
> commands/Makefile | 1 +
> commands/ums.c | 53 +
> drivers/usb/gadget/Kconfig | 11 +
> drivers/usb/gadget/Makefile | 1 +
> drivers/usb/gadget/f_mass_storage.c | 2936 +++++++++++++++++++++++++++
> drivers/usb/gadget/storage_common.c | 173 ++
> drivers/usb/gadget/storage_common.h | 245 +++
> include/scsi.h | 12 +
> include/usb/mass_storage.h | 28 +
> include/usb/storage.h | 87 +
> 10 files changed, 3547 insertions(+)
> create mode 100644 commands/ums.c
> create mode 100644 drivers/usb/gadget/f_mass_storage.c
> create mode 100644 drivers/usb/gadget/storage_common.c
> create mode 100644 drivers/usb/gadget/storage_common.h
> create mode 100644 include/usb/mass_storage.h
> create mode 100644 include/usb/storage.h
>
> diff --git a/commands/Makefile b/commands/Makefile
> index 034c0e6383d3..a31d5c877703 100644
> --- a/commands/Makefile
> +++ b/commands/Makefile
> @@ -130,5 +130,6 @@ obj-$(CONFIG_CMD_NAND_BITFLIP) += nand-bitflip.o
> obj-$(CONFIG_CMD_SEED) += seed.o
> obj-$(CONFIG_CMD_IP_ROUTE_GET) += ip-route-get.o
> obj-$(CONFIG_CMD_UBSAN) += ubsan.o
> +obj-$(CONFIG_USB_GADGET_MASS_STORAGE) += ums.o
>
> UBSAN_SANITIZE_ubsan.o := y
> diff --git a/commands/ums.c b/commands/ums.c
> new file mode 100644
> index 000000000000..0bc2cfdf5e98
> --- /dev/null
> +++ b/commands/ums.c
> @@ -0,0 +1,53 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2011 Samsung Electronics
> + * Lukasz Majewski <l.majewski@samsung.com>
> + *
> + * Copyright (c) 2015, NVIDIA CORPORATION. All rights reserved.
> + */
> +
> +#include <common.h>
> +#include <command.h>
> +#include <errno.h>
> +#include <malloc.h>
> +#include <getopt.h>
> +#include <fs.h>
> +#include <xfuncs.h>
> +#include <file-list.h>
> +#include <usb/mass_storage.h>
> +#include <linux/err.h>
> +
> +static int do_usb_mass_storage(int argc, char *argv[])
> +{
> + struct f_ums_opts opts;
> + char *argstr;
> + int ret;
> +
> + if (argc != optind + 1)
> + return COMMAND_ERROR_USAGE;
> +
> + argstr = argv[optind];
> +
> + opts.files = file_list_parse(argstr);
> + if (IS_ERR(opts.files)) {
> + ret = PTR_ERR(opts.files);
> + goto out;
> + }
> +
> + ret = usb_ums_register(&opts);
> +
> + file_list_free(opts.files);
> +out:
> + return ret;
> +}
> +
> +BAREBOX_CMD_HELP_START(usb)
> +BAREBOX_CMD_HELP_TEXT("Turn's the USB host into a UMS (USB Mass storage) gadget")
> +BAREBOX_CMD_HELP_END
> +
> +BAREBOX_CMD_START(ums)
> + .cmd = do_usb_mass_storage,
> + BAREBOX_CMD_DESC("USB mass storage gadget")
> + BAREBOX_CMD_GROUP(CMD_GRP_MISC)
> + BAREBOX_CMD_HELP(cmd_usb_help)
> +BAREBOX_CMD_END
> diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
> index 7e0c570914d7..90d2378b5b72 100644
> --- a/drivers/usb/gadget/Kconfig
> +++ b/drivers/usb/gadget/Kconfig
> @@ -59,4 +59,15 @@ config USB_GADGET_FASTBOOT
> select FILE_LIST
> select FASTBOOT_BASE
> prompt "Android Fastboot USB Gadget"
> +
> +config USB_GADGET_MASS_STORAGE
> + bool
> + select FILE_LIST
> + prompt "USB Mass Storage Gadget"
> + help
> + The Mass Storage Gadget acts as a USB Mass Storage disk drive.
> + As its storage repository it can use a regular file or a block
> + device. Multiple storages can be specified at once on
> + instantiation time.
> +
> endif
> diff --git a/drivers/usb/gadget/Makefile b/drivers/usb/gadget/Makefile
> index 27673fcf0ef6..5ba4920c085a 100644
> --- a/drivers/usb/gadget/Makefile
> +++ b/drivers/usb/gadget/Makefile
> @@ -3,6 +3,7 @@ obj-$(CONFIG_USB_GADGET) += composite.o config.o usbstring.o epautoconf.o udc-co
> obj-$(CONFIG_USB_GADGET_SERIAL) += u_serial.o serial.o f_serial.o f_acm.o
> obj-$(CONFIG_USB_GADGET_DFU) += dfu.o
> obj-$(CONFIG_USB_GADGET_FASTBOOT) += f_fastboot.o
> +obj-$(CONFIG_USB_GADGET_MASS_STORAGE) += f_mass_storage.o storage_common.o
> obj-$(CONFIG_USB_GADGET_DRIVER_ARC) += fsl_udc.o
> pbl-$(CONFIG_USB_GADGET_DRIVER_ARC_PBL) += fsl_udc_pbl.o
> obj-$(CONFIG_USB_GADGET_DRIVER_AT91) += at91_udc.o
> diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c
> new file mode 100644
> index 000000000000..9c0076be26d1
> --- /dev/null
> +++ b/drivers/usb/gadget/f_mass_storage.c
> @@ -0,0 +1,2936 @@
> +// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
> +/*
> + * f_mass_storage.c -- Mass Storage USB Composite Function
> + *
> + * Copyright (C) 2003-2008 Alan Stern
> + * Copyright (C) 2009 Samsung Electronics
> + * Author: Michal Nazarewicz <m.nazarewicz@samsung.com>
> + * All rights reserved.
> + */
> +
> +/*
> + * The Mass Storage Function acts as a USB Mass Storage device,
> + * appearing to the host as a disk drive or as a CD-ROM drive. In
> + * addition to providing an example of a genuinely useful composite
> + * function for a USB device, it also illustrates a technique of
> + * double-buffering for increased throughput.
> + *
> + * Function supports multiple logical units (LUNs). Backing storage
> + * for each LUN is provided by a regular file or a block device.
> + * Access for each LUN can be limited to read-only. Moreover, the
> + * function can indicate that LUN is removable and/or CD-ROM. (The
> + * later implies read-only access.)
> + *
> + * MSF is configured by specifying a fsg_config structure. It has the
> + * following fields:
> + *
> + * nluns Number of LUNs function have (anywhere from 1
> + * to FSG_MAX_LUNS which is 8).
> + * luns An array of LUN configuration values. This
> + * should be filled for each LUN that
> + * function will include (ie. for "nluns"
> + * LUNs). Each element of the array has
> + * the following fields:
> + * ->filename The path to the backing file for the LUN.
> + * Required if LUN is not marked as
> + * removable.
> + * ->ro Flag specifying access to the LUN shall be
> + * read-only. This is implied if CD-ROM
> + * emulation is enabled as well as when
> + * it was impossible to open "filename"
> + * in R/W mode.
> + * ->removable Flag specifying that LUN shall be indicated as
> + * being removable.
> + * ->cdrom Flag specifying that LUN shall be reported as
> + * being a CD-ROM.
> + *
> + * lun_name_format A printf-like format for names of the LUN
> + * devices. This determines how the
> + * directory in sysfs will be named.
> + * Unless you are using several MSFs in
> + * a single gadget (as opposed to single
> + * MSF in many configurations) you may
> + * leave it as NULL (in which case
> + * "lun%d" will be used). In the format
> + * you can use "%d" to index LUNs for
> + * MSF's with more than one LUN. (Beware
> + * that there is only one integer given
> + * as an argument for the format and
> + * specifying invalid format may cause
> + * unspecified behaviour.)
> + * thread_name Name of the kernel thread process used by the
> + * MSF. You can safely set it to NULL
> + * (in which case default "file-storage"
> + * will be used).
> + *
> + * vendor_name
> + * product_name
> + * release Information used as a reply to INQUIRY
> + * request. To use default set to NULL,
> + * NULL, 0xffff respectively. The first
> + * field should be 8 and the second 16
> + * characters or less.
> + *
> + * can_stall Set to permit function to halt bulk endpoints.
> + * Disabled on some USB devices known not
> + * to work correctly. You should set it
> + * to true.
> + *
> + * If "removable" is not set for a LUN then a backing file must be
> + * specified. If it is set, then NULL filename means the LUN's medium
> + * is not loaded (an empty string as "filename" in the fsg_config
> + * structure causes error). The CD-ROM emulation includes a single
> + * data track and no audio tracks; hence there need be only one
> + * backing file per LUN. Note also that the CD-ROM block length is
> + * set to 512 rather than the more common value 2048.
> + *
> + *
> + * MSF includes support for module parameters. If gadget using it
> + * decides to use it, the following module parameters will be
> + * available:
> + *
> + * file=filename[,filename...]
> + * Names of the files or block devices used for
> + * backing storage.
> + * ro=b[,b...] Default false, boolean for read-only access.
> + * removable=b[,b...]
> + * Default true, boolean for removable media.
> + * cdrom=b[,b...] Default false, boolean for whether to emulate
> + * a CD-ROM drive.
> + * luns=N Default N = number of filenames, number of
> + * LUNs to support.
> + * stall Default determined according to the type of
> + * USB device controller (usually true),
> + * boolean to permit the driver to halt
> + * bulk endpoints.
> + *
> + * The module parameters may be prefixed with some string. You need
> + * to consult gadget's documentation or source to verify whether it is
> + * using those module parameters and if it does what are the prefixes
> + * (look for FSG_MODULE_PARAMETERS() macro usage, what's inside it is
> + * the prefix).
> + *
> + *
> + * Requirements are modest; only a bulk-in and a bulk-out endpoint are
> + * needed. The memory requirement amounts to two 16K buffers, size
> + * configurable by a parameter. Support is included for both
> + * full-speed and high-speed operation.
> + *
> + * Note that the driver is slightly non-portable in that it assumes a
> + * single memory/DMA buffer will be useable for bulk-in, bulk-out, and
> + * interrupt-in endpoints. With most device controllers this isn't an
> + * issue, but there may be some with hardware restrictions that prevent
> + * a buffer from being used by more than one endpoint.
> + *
> + *
> + * The pathnames of the backing files and the ro settings are
> + * available in the attribute files "file" and "ro" in the lun<n> (or
> + * to be more precise in a directory which name comes from
> + * "lun_name_format" option!) subdirectory of the gadget's sysfs
> + * directory. If the "removable" option is set, writing to these
> + * files will simulate ejecting/loading the medium (writing an empty
> + * line means eject) and adjusting a write-enable tab. Changes to the
> + * ro setting are not allowed when the medium is loaded or if CD-ROM
> + * emulation is being used.
> + *
> + * When a LUN receive an "eject" SCSI request (Start/Stop Unit),
> + * if the LUN is removable, the backing file is released to simulate
> + * ejection.
> + *
> + *
> + * This function is heavily based on "File-backed Storage Gadget" by
> + * Alan Stern which in turn is heavily based on "Gadget Zero" by David
> + * Brownell. The driver's SCSI command interface was based on the
> + * "Information technology - Small Computer System Interface - 2"
> + * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
> + * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
> + * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
> + * was based on the "Universal Serial Bus Mass Storage Class UFI
> + * Command Specification" document, Revision 1.0, December 14, 1998,
> + * available at
> + * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
> + */
> +
> +/*
> + * Driver Design
> + *
> + * The MSF is fairly straightforward. There is a main kernel
> + * thread that handles most of the work. Interrupt routines field
> + * callbacks from the controller driver: bulk- and interrupt-request
> + * completion notifications, endpoint-0 events, and disconnect events.
> + * Completion events are passed to the main thread by wakeup calls. Many
> + * ep0 requests are handled at interrupt time, but SetInterface,
> + * SetConfiguration, and device reset requests are forwarded to the
> + * thread in the form of "exceptions" using SIGUSR1 signals (since they
> + * should interrupt any ongoing file I/O operations).
> + *
> + * The thread's main routine implements the standard command/data/status
> + * parts of a SCSI interaction. It and its subroutines are full of tests
> + * for pending signals/exceptions -- all this polling is necessary since
> + * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
> + * indication that the driver really wants to be running in userspace.)
> + * An important point is that so long as the thread is alive it keeps an
> + * open reference to the backing file. This will prevent unmounting
> + * the backing file's underlying filesystem and could cause problems
> + * during system shutdown, for example. To prevent such problems, the
> + * thread catches INT, TERM, and KILL signals and converts them into
> + * an EXIT exception.
> + *
> + * In normal operation the main thread is started during the gadget's
> + * fsg_bind() callback and stopped during fsg_unbind(). But it can
> + * also exit when it receives a signal, and there's no point leaving
> + * the gadget running when the thread is dead. At of this moment, MSF
> + * provides no way to deregister the gadget when thread dies -- maybe
> + * a callback functions is needed.
> + *
> + * To provide maximum throughput, the driver uses a circular pipeline of
> + * buffer heads (struct fsg_buffhd). In principle the pipeline can be
> + * arbitrarily long; in practice the benefits don't justify having more
> + * than 2 stages (i.e., double buffering). But it helps to think of the
> + * pipeline as being a long one. Each buffer head contains a bulk-in and
> + * a bulk-out request pointer (since the buffer can be used for both
> + * output and input -- directions always are given from the host's
> + * point of view) as well as a pointer to the buffer and various state
> + * variables.
> + *
> + * Use of the pipeline follows a simple protocol. There is a variable
> + * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
> + * At any time that buffer head may still be in use from an earlier
> + * request, so each buffer head has a state variable indicating whether
> + * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
> + * buffer head to be EMPTY, filling the buffer either by file I/O or by
> + * USB I/O (during which the buffer head is BUSY), and marking the buffer
> + * head FULL when the I/O is complete. Then the buffer will be emptied
> + * (again possibly by USB I/O, during which it is marked BUSY) and
> + * finally marked EMPTY again (possibly by a completion routine).
> + *
> + * A module parameter tells the driver to avoid stalling the bulk
> + * endpoints wherever the transport specification allows. This is
> + * necessary for some UDCs like the SuperH, which cannot reliably clear a
> + * halt on a bulk endpoint. However, under certain circumstances the
> + * Bulk-only specification requires a stall. In such cases the driver
> + * will halt the endpoint and set a flag indicating that it should clear
> + * the halt in software during the next device reset. Hopefully this
> + * will permit everything to work correctly. Furthermore, although the
> + * specification allows the bulk-out endpoint to halt when the host sends
> + * too much data, implementing this would cause an unavoidable race.
> + * The driver will always use the "no-stall" approach for OUT transfers.
> + *
> + * One subtle point concerns sending status-stage responses for ep0
> + * requests. Some of these requests, such as device reset, can involve
> + * interrupting an ongoing file I/O operation, which might take an
> + * arbitrarily long time. During that delay the host might give up on
> + * the original ep0 request and issue a new one. When that happens the
> + * driver should not notify the host about completion of the original
> + * request, as the host will no longer be waiting for it. So the driver
> + * assigns to each ep0 request a unique tag, and it keeps track of the
> + * tag value of the request associated with a long-running exception
> + * (device-reset, interface-change, or configuration-change). When the
> + * exception handler is finished, the status-stage response is submitted
> + * only if the current ep0 request tag is equal to the exception request
> + * tag. Thus only the most recently received ep0 request will get a
> + * status-stage response.
> + *
> + * Warning: This driver source file is too long. It ought to be split up
> + * into a header file plus about 3 separate .c files, to handle the details
> + * of the Gadget, USB Mass Storage, and SCSI protocols.
> + */
> +
> +/* #define VERBOSE_DEBUG */
> +/* #define DUMP_MSGS */
> +
> +#define pr_fmt(fmt) "f_ums: " fmt
> +
> +#include <common.h>
> +#include <unistd.h>
> +#include <linux/stat.h>
> +#include <linux/wait.h>
> +#include <fcntl.h>
> +#include <file-list.h>
> +#include <dma.h>
> +#include <linux/bug.h>
> +#include <linux/rwsem.h>
> +#include <linux/pagemap.h>
> +#include <disks.h>
> +#include <scsi.h>
> +
> +#include <linux/err.h>
> +#include <usb/mass_storage.h>
> +
> +#include <asm/unaligned.h>
> +#include <linux/bitops.h>
> +#include <usb/gadget.h>
> +#include <usb/composite.h>
> +#include <linux/bitmap.h>
> +
> +/*------------------------------------------------------------------------*/
> +
> +#define FSG_DRIVER_DESC "ums"
> +#define UMS_NAME_LEN 16
> +
> +#define FSG_DRIVER_VERSION "2012/06/5"
> +
> +static const char fsg_string_interface[] = "Mass Storage";
> +
> +#include "storage_common.h"
> +
> +/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
> +struct usb_string fsg_strings[] = {
> + {FSG_STRING_INTERFACE, fsg_string_interface},
> + {}
> +};
> +
> +static struct usb_gadget_strings fsg_stringtab = {
> + .language = 0x0409, /* en-us */
> + .strings = fsg_strings,
> +};
> +
> +/*-------------------------------------------------------------------------*/
> +
> +struct completion { int done; };
> +
> +#define init_completion(x) do { (x)->done = 0; } while (0)
> +#define reinit_completion(x) init_completion(x)
> +static inline int wait_for_completion_interruptible(struct completion *x)
> +{
> + int ret;
> +
> + while (!x->done) {
> + ret = ctrlc();
> + if (ret)
> + return -ERESTARTSYS;
> + }
> +
> + return 0;
> +}
> +#define complete_and_exit(...) return 0
> +
> +static inline void complete(struct completion *x)
> +{
> + x->done = 1;
> +}
> +
> +struct task_struct {
> + int (*threadfn)(void *);
> + void *arg;
> +};
> +
> +static struct task_struct *kthread_run(int (*threadfn)(void *), void *arg,
> + const char *name)
> +{
> + struct task_struct *task;
> +
> + task = xmalloc(sizeof(*task));
> + task->threadfn = threadfn;
> + task->arg = arg;
> +
> + return task;
> +}
> +
> +#define free_kthread_struct(t) free(t)
> +
> +#define poll() thread_task->threadfn(thread_task->arg)
> +
> +#define wait_event(queue, cond) do { poll(); } while (!(cond))
> +#define wake_up(...) do {} while (0)
> +
> +struct task_struct *thread_task;
> +
> +/*-------------------------------------------------------------------------*/
> +
> +struct kref {int x; };
> +
> +struct fsg_dev;
> +
> +static struct file_list *ums_files;
> +
> +static struct usb_device_descriptor ums_dev_descriptor = {
> + .bLength = USB_DT_DEVICE_SIZE,
> + .bDescriptorType = USB_DT_DEVICE,
> + .bcdUSB = __constant_cpu_to_le16(0x0200),
> + .bDeviceClass = USB_CLASS_PER_INTERFACE,
> + .bNumConfigurations = 1,
> +};
> +
> +/* Data shared by all the FSG instances. */
> +struct fsg_common {
> + struct usb_gadget *gadget;
> + struct fsg_dev *fsg, *new_fsg;
> +
> + wait_queue_head_t fsg_wait;
> + struct usb_ep *ep0; /* Copy of gadget->ep0 */
> + struct usb_request *ep0req; /* Copy of cdev->req */
> + unsigned int ep0_req_tag;
> +
> + struct fsg_buffhd *next_buffhd_to_fill;
> + struct fsg_buffhd *next_buffhd_to_drain;
> + struct fsg_buffhd buffhds[FSG_NUM_BUFFERS];
> +
> + int cmnd_size;
> + u8 cmnd[MAX_COMMAND_SIZE];
> +
> + unsigned int nluns;
> + unsigned int lun;
> + struct fsg_lun luns[FSG_MAX_LUNS];
> +
> + unsigned int bulk_out_maxpacket;
> + enum fsg_state state; /* For exception handling */
> + unsigned int exception_req_tag;
> +
> + enum data_direction data_dir;
> + u32 data_size;
> + u32 data_size_from_cmnd;
> + u32 tag;
> + u32 residue;
> + u32 usb_amount_left;
> +
> + unsigned int can_stall:1;
> + unsigned int free_storage_on_release:1;
> + unsigned int phase_error:1;
> + unsigned int short_packet_received:1;
> + unsigned int bad_lun_okay:1;
> + unsigned int running:1;
> +
> + struct completion thread_wakeup_needed;
> + struct completion thread_notifier;
> + bool shutdown;
> +
> + /* Callback functions. */
> + const struct fsg_operations *ops;
> + /* Gadget's private data. */
> + void *private_data;
> +
> + const char *vendor_name; /* 8 characters or less */
> + const char *product_name; /* 16 characters or less */
> + u16 release;
> +
> + /* Vendor (8 chars), product (16 chars), release (4
> + * hexadecimal digits) and NUL byte */
> + char inquiry_string[8 + 16 + 4 + 1];
> +
> + struct kref ref;
> +};
> +
> +struct fsg_config {
> + unsigned nluns;
> + struct fsg_lun_config {
> + const char *filename;
> + char ro;
> + char removable;
> + char cdrom;
> + char nofua;
> + } luns[FSG_MAX_LUNS];
> +
> + /* Callback functions. */
> + const struct fsg_operations *ops;
> + /* Gadget's private data. */
> + void *private_data;
> +
> + const char *vendor_name; /* 8 characters or less */
> + const char *product_name; /* 16 characters or less */
> +
> + char can_stall;
> +};
> +
> +struct fsg_dev {
> + struct usb_function function;
> + struct usb_gadget *gadget; /* Copy of cdev->gadget */
> + struct fsg_common *common;
> +
> + u16 interface_number;
> +
> + unsigned int bulk_in_enabled:1;
> + unsigned int bulk_out_enabled:1;
> +
> + unsigned long atomic_bitflags;
> +#define IGNORE_BULK_OUT 0
> +
> + struct usb_ep *bulk_in;
> + struct usb_ep *bulk_out;
> +};
> +
> +
> +static inline int __fsg_is_set(struct fsg_common *common,
> + const char *func, unsigned line)
> +{
> + if (common->fsg)
> + return 1;
> + ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
> + WARN_ON(1);
> +
> + return 0;
> +}
> +
> +#define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
> +
> +
> +static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
> +{
> + return container_of(f, struct fsg_dev, function);
> +}
> +
> +static inline struct f_ums_opts *
> +fsg_opts_from_func_inst(const struct usb_function_instance *fi)
> +{
> + return container_of(fi, struct f_ums_opts, func_inst);
> +}
> +
> +typedef void (*fsg_routine_t)(struct fsg_dev *);
> +
> +static int exception_in_progress(struct fsg_common *common)
> +{
> + return common->state > FSG_STATE_IDLE;
> +}
> +
> +/* Make bulk-out requests be divisible by the maxpacket size */
> +static void set_bulk_out_req_length(struct fsg_common *common,
> + struct fsg_buffhd *bh, unsigned int length)
> +{
> + unsigned int rem;
> +
> + bh->bulk_out_intended_length = length;
> + rem = length % common->bulk_out_maxpacket;
> + if (rem > 0)
> + length += common->bulk_out_maxpacket - rem;
> + bh->outreq->length = length;
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +static struct f_ums_opts ums[14]; // FIXME
> +static int ums_count;
> +
> +static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
> +{
> + const char *name;
> +
> + if (ep == fsg->bulk_in)
> + name = "bulk-in";
> + else if (ep == fsg->bulk_out)
> + name = "bulk-out";
> + else
> + name = ep->name;
> + DBG(fsg, "%s set halt\n", name);
> + return usb_ep_set_halt(ep);
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +/* These routines may be called in process context or in_irq */
> +
> +/* Caller must hold fsg->lock */
> +static void wakeup_thread(struct fsg_common *common)
> +{
> + complete(&common->thread_wakeup_needed);
> +}
> +
> +static void report_exception(const char *prefix, enum fsg_state state)
> +{
> + const char *msg = "<unknown>";
> + switch (state) {
> + /* This one isn't used anywhere */
> + case FSG_STATE_COMMAND_PHASE:
> + msg = "Command Phase";
> + break;
> + case FSG_STATE_DATA_PHASE:
> + msg = "Data Phase";
> + break;
> + case FSG_STATE_STATUS_PHASE:
> + msg = "Status Phase";
> + break;
> +
> + case FSG_STATE_IDLE:
> + msg = "Idle";
> + break;
> + case FSG_STATE_ABORT_BULK_OUT:
> + msg = "abort bulk out";
> + break;
> + case FSG_STATE_RESET:
> + msg = "reset";
> + break;
> + case FSG_STATE_INTERFACE_CHANGE:
> + msg = "interface change";
> + break;
> + case FSG_STATE_CONFIG_CHANGE:
> + msg = "config change";
> + break;
> + case FSG_STATE_DISCONNECT:
> + msg = "disconnect";
> + break;
> + case FSG_STATE_EXIT:
> + msg = "exit";
> + break;
> + case FSG_STATE_TERMINATED:
> + msg = "terminated";
> + break;
> + }
> +
> + pr_debug("%s: %s\n", prefix, msg);
> +}
> +
> +static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
> +{
> + /* 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. */
> + if (common->state <= new_state) {
> + report_exception("raising (preempted)", new_state);
> + common->exception_req_tag = common->ep0_req_tag;
> + common->state = new_state;
> + wakeup_thread(common);
> + }
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +static int ep0_queue(struct fsg_common *common)
> +{
> + int rc;
> +
> + rc = usb_ep_queue(common->ep0, common->ep0req);
> + common->ep0->driver_data = common;
> + if (rc != 0 && rc != -ESHUTDOWN) {
> + /* We can't do much more than wait for a reset */
> + WARNING(common, "error in submission: %s --> %d\n",
> + common->ep0->name, rc);
> + }
> + return rc;
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +/* 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_common *common = ep->driver_data;
> + struct fsg_buffhd *bh = req->context;
> +
> + if (req->status || req->actual != req->length)
> + DBG(common, "%s --> %d, %u/%u\n", __func__,
> + req->status, req->actual, req->length);
> + if (req->status == -ECONNRESET) /* Request was cancelled */
> + usb_ep_fifo_flush(ep);
> +
> + /* Hold the lock while we update the request and buffer states */
> + bh->inreq_busy = 0;
> + bh->state = BUF_STATE_EMPTY;
> + wakeup_thread(common);
> +}
> +
> +static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
> +{
> + struct fsg_common *common = ep->driver_data;
> + struct fsg_buffhd *bh = req->context;
> +
> + dump_msg(common, "bulk-out", req->buf, req->actual);
> + if (req->status || req->actual != bh->bulk_out_intended_length)
> + DBG(common, "%s --> %d, %u/%u\n", __func__,
> + req->status, req->actual,
> + bh->bulk_out_intended_length);
> + if (req->status == -ECONNRESET) /* Request was cancelled */
> + usb_ep_fifo_flush(ep);
> +
> + /* Hold the lock while we update the request and buffer states */
> + bh->outreq_busy = 0;
> + bh->state = BUF_STATE_FULL;
> + wakeup_thread(common);
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +/* Ep0 class-specific handlers. These always run in_irq. */
> +
> +static int fsg_setup(struct usb_function *f,
> + const struct usb_ctrlrequest *ctrl)
> +{
> + struct fsg_dev *fsg = fsg_from_func(f);
> + struct usb_request *req = fsg->common->ep0req;
> + u16 w_index = get_unaligned_le16(&ctrl->wIndex);
> + u16 w_value = get_unaligned_le16(&ctrl->wValue);
> + u16 w_length = get_unaligned_le16(&ctrl->wLength);
> +
> + if (!fsg_is_set(fsg->common))
> + return -EOPNOTSUPP;
> +
> + switch (ctrl->bRequest) {
> +
> + case US_BULK_RESET_REQUEST:
> + if (ctrl->bRequestType !=
> + (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
> + break;
> + if (w_index != fsg->interface_number || w_value != 0)
> + return -EDOM;
> +
> + /* Raise an exception to stop the current operation
> + * and reinitialize our state. */
> + DBG(fsg, "bulk reset request\n");
> + raise_exception(fsg->common, FSG_STATE_RESET);
> + return DELAYED_STATUS;
> +
> + case US_BULK_GET_MAX_LUN:
> + if (ctrl->bRequestType !=
> + (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
> + break;
> + if (w_index != fsg->interface_number || w_value != 0)
> + return -EDOM;
> + VDBG(fsg, "get max LUN\n");
> + *(u8 *) req->buf = fsg->common->nluns - 1;
> +
> + /* Respond with data/status */
> + req->length = min((u16)1, w_length);
> + return ep0_queue(fsg->common);
> + }
> +
> + VDBG(fsg,
> + "unknown class-specific control req "
> + "%02x.%02x v%04x i%04x l%u\n",
> + ctrl->bRequestType, ctrl->bRequest,
> + get_unaligned_le16(&ctrl->wValue), w_index, w_length);
> + return -EOPNOTSUPP;
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +/* All the following routines run in process context */
> +
> +/* Use this for bulk or interrupt transfers, not ep0 */
> +static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
> + struct usb_request *req, int *pbusy,
> + enum fsg_buffer_state *state)
> +{
> + int rc;
> +
> + if (ep == fsg->bulk_in)
> + dump_msg(fsg, "bulk-in", req->buf, req->length);
> +
> + *pbusy = 1;
> + *state = BUF_STATE_BUSY;
> + rc = usb_ep_queue(ep, req);
> + 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);
> + }
> +}
> +
> +#define START_TRANSFER_OR(common, ep_name, req, pbusy, state) \
> + if (fsg_is_set(common)) \
> + start_transfer((common)->fsg, (common)->fsg->ep_name, \
> + req, pbusy, state); \
> + else
> +
> +#define START_TRANSFER(common, ep_name, req, pbusy, state) \
> + START_TRANSFER_OR(common, ep_name, req, pbusy, state) (void)0
> +
> +static int sleep_thread(struct fsg_common *common)
> +{
> + int ret;
> +
> + /* Wait until a signal arrives or we are woken up */
> + ret = wait_for_completion_interruptible(&common->thread_wakeup_needed);
> + if (ret) {
> + /* If we run outside of a poller, this ensures we exit the loop */
> + common->running = false;
> + return ret;
> + }
> +
> + if (common->shutdown)
> + return -ERESTARTSYS;
> +
> + reinit_completion(&common->thread_wakeup_needed);
> + return 0;
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +static int do_read(struct fsg_common *common)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> + u32 lba;
> + struct fsg_buffhd *bh;
> + int rc;
> + u32 amount_left;
> + loff_t file_offset;
> + unsigned int amount;
> + unsigned int partial_page;
> + ssize_t nread;
> +
> + /* Get the starting Logical Block Address and check that it's
> + * not too big */
> + if (common->cmnd[0] == SCSI_READ6)
> + lba = get_unaligned_be24(&common->cmnd[1]);
> + else {
> + lba = get_unaligned_be32(&common->cmnd[2]);
> +
> + /* We allow DPO (Disable Page Out = don't save data in the
> + * cache) and FUA (Force Unit Access = don't read from the
> + * cache), but we don't implement them. */
> + if ((common->cmnd[1] & ~0x18) != 0) {
> + curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
> + return -EINVAL;
> + }
> + }
> + if (lba >= curlun->num_sectors) {
> + curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
> + return -EINVAL;
> + }
> + file_offset = ((loff_t) lba) << 9;
> +
> + /* Carry out the file reads */
> + amount_left = common->data_size_from_cmnd;
> + if (unlikely(amount_left == 0))
> + return -EIO; /* No default reply */
> +
> + for (;;) {
> + /* Wait for the next buffer to become available */
> + bh = common->next_buffhd_to_fill;
> + while (bh->state != BUF_STATE_EMPTY) {
> + rc = sleep_thread(common);
> + if (rc)
> + return rc;
> + }
> +
> + /* Figure out how much we need to read:
> + * Try to read the remaining amount.
> + * But don't read more than the buffer size.
> + * And don't try to read past the end of the file.
> + * Finally, if we're not at a page boundary, don't read past
> + * the next page.
> + * If this means reading 0 then we were asked to read past
> + * the end of file. */
> + amount = min(amount_left, FSG_BUFLEN);
> + partial_page = file_offset & (PAGE_CACHE_SIZE - 1);
> + if (partial_page > 0)
> + amount = min(amount, (unsigned int) PAGE_CACHE_SIZE -
> + partial_page);
> +
> +
> + /* 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->info_valid = 1;
> + bh->inreq->length = 0;
> + bh->state = BUF_STATE_FULL;
> + break;
> + }
> +
> + /* Perform the read */
> + nread = pread(ums[common->lun].fd, bh->buf, amount, file_offset);
> +
> + VLDBG(curlun, "file read %u @ %llu -> %zd\n", amount,
> + (unsigned long long) file_offset,
> + nread);
> + if (nread <= 0) {
> + const char *err = nread ? strerror(-nread) : "EOF";
> + LDBG(curlun, "error in file read: %s\n", err);
> + nread = 0;
> + } else if (nread < amount) {
> + LDBG(curlun, "partial file read: %d/%u\n",
> + (int) nread, amount);
> + nread -= (nread & 511); /* Round down to a block */
> + }
> + file_offset += nread;
> + amount_left -= nread;
> + common->residue -= nread;
> + bh->inreq->length = nread;
> + bh->state = BUF_STATE_FULL;
> +
> + /* If an error occurred, report it and its position */
> + if (nread < amount) {
> + curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
> + curlun->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_OR(common, bulk_in, bh->inreq,
> + &bh->inreq_busy, &bh->state)
> + /* Don't know what to do if
> + * common->fsg is NULL */
> + return -EIO;
> + common->next_buffhd_to_fill = bh->next;
> + }
> +
> + return -EIO; /* No default reply */
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +static int do_write(struct fsg_common *common)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> + 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;
> + unsigned int amount;
> + unsigned int partial_page;
> + ssize_t nwritten;
> + int rc;
> +
> + if (curlun->ro) {
> + curlun->sense_data = SS_WRITE_PROTECTED;
> + return -EINVAL;
> + }
> +
> + /* Get the starting Logical Block Address and check that it's
> + * not too big */
> + if (common->cmnd[0] == SCSI_WRITE6)
> + lba = get_unaligned_be24(&common->cmnd[1]);
> + else {
> + lba = get_unaligned_be32(&common->cmnd[2]);
> +
> + /* We allow DPO (Disable Page Out = don't save data in the
> + * cache) and FUA (Force Unit Access = write directly to the
> + * medium). We don't implement DPO; we implement FUA by
> + * performing synchronous output. */
> + if (common->cmnd[1] & ~0x18) {
> + curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
> + return -EINVAL;
> + }
> + }
> + if (lba >= curlun->num_sectors) {
> + curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
> + return -EINVAL;
> + }
> +
> + /* Carry out the file writes */
> + get_some_more = 1;
> + file_offset = usb_offset = ((loff_t) lba) << 9;
> + amount_left_to_req = common->data_size_from_cmnd;
> + amount_left_to_write = common->data_size_from_cmnd;
> +
> + while (amount_left_to_write > 0) {
> +
> + /* Queue a request for more data from the host */
> + bh = common->next_buffhd_to_fill;
> + if (bh->state == BUF_STATE_EMPTY && get_some_more) {
> +
> + /* Figure out how much we want to get:
> + * Try to get the remaining amount.
> + * But don't get more than the buffer size.
> + * And don't try to go past the end of the file.
> + * If we're not at a page boundary,
> + * don't go past the next page.
> + * If this means getting 0, then we were asked
> + * to write past the end of file.
> + * Finally, round down to a block boundary. */
> + amount = min(amount_left_to_req, FSG_BUFLEN);
> + 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->info_valid = 1;
> + continue;
> + }
> + amount -= (amount & 511);
> + if (amount == 0) {
> +
> + /* Why were we were asked to transfer a
> + * partial block? */
> + get_some_more = 0;
> + continue;
> + }
> +
> + /* Get the next buffer */
> + usb_offset += amount;
> + common->usb_amount_left -= amount;
> + amount_left_to_req -= amount;
> + if (amount_left_to_req == 0)
> + get_some_more = 0;
> +
> + /* amount is always divisible by 512, hence by
> + * the bulk-out maxpacket size */
> + bh->outreq->length = amount;
> + bh->bulk_out_intended_length = amount;
> + bh->outreq->short_not_ok = 1;
> + START_TRANSFER_OR(common, bulk_out, bh->outreq,
> + &bh->outreq_busy, &bh->state)
> + /* Don't know what to do if
> + * common->fsg is NULL */
> + return -EIO;
> + common->next_buffhd_to_fill = bh->next;
> + continue;
> + }
> +
> + /* Write the received data to the backing file */
> + bh = common->next_buffhd_to_drain;
> + if (bh->state == BUF_STATE_EMPTY && !get_some_more)
> + break; /* We stopped early */
> + if (bh->state == BUF_STATE_FULL) {
> + common->next_buffhd_to_drain = bh->next;
> + bh->state = BUF_STATE_EMPTY;
> +
> + /* Did something go wrong with the transfer? */
> + if (bh->outreq->status != 0) {
> + curlun->sense_data = SS_COMMUNICATION_FAILURE;
> + curlun->info_valid = 1;
> + break;
> + }
> +
> + amount = bh->outreq->actual;
> +
> + /* Perform the write */
> + nwritten = pwrite(ums[common->lun].fd, bh->buf, amount, file_offset);
> +
> + VLDBG(curlun, "file write %u @ %llu -> %zd\n", amount,
> + (unsigned long long) file_offset,
> + nwritten);
> +
> + if (nwritten < 0) {
> + LDBG(curlun, "error in file write: %pe\n", ERR_PTR(nwritten));
> + nwritten = 0;
> + } else if (nwritten < amount) {
> + LDBG(curlun, "partial file write: %d/%u\n",
> + (int) nwritten, amount);
> + nwritten -= (nwritten & 511);
> + /* Round down to a block */
> + }
> + file_offset += nwritten;
> + amount_left_to_write -= nwritten;
> + common->residue -= nwritten;
> +
> + /* If an error occurred, report it and its position */
> + if (nwritten < amount) {
> + pr_warn("nwritten:%zd amount:%u\n", nwritten,
> + amount);
> + curlun->sense_data = SS_WRITE_ERROR;
> + curlun->info_valid = 1;
> + break;
> + }
> +
> + /* Did the host decide to stop early? */
> + if (bh->outreq->actual != bh->outreq->length) {
> + common->short_packet_received = 1;
> + break;
> + }
> + continue;
> + }
> +
> + /* Wait for something to happen */
> + rc = sleep_thread(common);
> + if (rc)
> + return rc;
> + }
> +
> + return -EIO; /* No default reply */
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +static int do_synchronize_cache(struct fsg_common *common)
> +{
> + return 0;
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +static int do_verify(struct fsg_common *common)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> + u32 lba;
> + u32 verification_length;
> + struct fsg_buffhd *bh = common->next_buffhd_to_fill;
> + loff_t file_offset;
> + u32 amount_left;
> + unsigned int amount;
> + ssize_t nread;
> +
> + /* Get the starting Logical Block Address and check that it's
> + * not too big */
> + lba = get_unaligned_be32(&common->cmnd[2]);
> + if (lba >= curlun->num_sectors) {
> + curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
> + return -EINVAL;
> + }
> +
> + /* We allow DPO (Disable Page Out = don't save data in the
> + * cache) but we don't implement it. */
> + if (common->cmnd[1] & ~0x10) {
> + curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
> + return -EINVAL;
> + }
> +
> + verification_length = get_unaligned_be16(&common->cmnd[7]);
> + if (unlikely(verification_length == 0))
> + return -EIO; /* No default reply */
> +
> + /* Prepare to carry out the file verify */
> + amount_left = verification_length << 9;
> + file_offset = ((loff_t) lba) << 9;
> +
> + /* Write out all the dirty buffers before invalidating them */
> +
> + /* Just try to read the requested blocks */
> + while (amount_left > 0) {
> +
> + /* Figure out how much we need to read:
> + * Try to read the remaining amount, but not more than
> + * the buffer size.
> + * And don't try to read past the end of the file.
> + * If this means reading 0 then we were asked to read
> + * past the end of file. */
> + amount = min(amount_left, FSG_BUFLEN);
> + if (amount == 0) {
> + curlun->sense_data =
> + SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
> + curlun->info_valid = 1;
> + break;
> + }
> +
> + /* Perform the read */
> + nread = pread(ums[common->lun].fd, bh->buf, amount, file_offset);
> +
> + VLDBG(curlun, "file read %u @ %llu -> %zd\n", amount,
> + (unsigned long long) file_offset,
> + nread);
> + if (nread <= 0) {
> + const char *err = nread ? strerror(-nread) : "EOF";
> + LDBG(curlun, "error in file read: %s\n", err);
> + 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->info_valid = 1;
> + break;
> + }
> + file_offset += nread;
> + amount_left -= nread;
> + }
> + return 0;
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> + static const char vendor_id[] = "Linux ";
> + u8 *buf = (u8 *) bh->buf;
> +
> + if (!curlun) { /* Unsupported LUNs are okay */
> + common->bad_lun_okay = 1;
> + memset(buf, 0, 36);
> + buf[0] = 0x7f; /* Unsupported, no device-type */
> + buf[4] = 31; /* Additional length */
> + return 36;
> + }
> +
> + memset(buf, 0, 8);
> + buf[0] = TYPE_DISK;
> + buf[1] = curlun->removable ? 0x80 : 0;
> + buf[2] = 2; /* ANSI SCSI level 2 */
> + buf[3] = 2; /* SCSI-2 INQUIRY data format */
> + buf[4] = 31; /* Additional length */
> + /* No special options */
> + sprintf((char *) (buf + 8), "%-8s%-16s%04x", (char*) vendor_id ,
> + ums[common->lun].name, (u16) 0xffff);
> +
> + return 36;
> +}
> +
> +
> +static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> + u8 *buf = (u8 *) bh->buf;
> + u32 sd, sdinfo = 0;
> + int valid;
> +
> + /*
> + * From the SCSI-2 spec., section 7.9 (Unit attention condition):
> + *
> + * If a REQUEST SENSE command is received from an initiator
> + * with a pending unit attention condition (before the target
> + * generates the contingent allegiance condition), then the
> + * target shall either:
> + * a) report any pending sense data and preserve the unit
> + * attention condition on the logical unit, or,
> + * b) report the unit attention condition, may discard any
> + * pending sense data, and clear the unit attention
> + * condition on the logical unit for that initiator.
> + *
> + * FSG normally uses option a); enable this code to use option b).
> + */
> +#if 0
> + if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
> + curlun->sense_data = curlun->unit_attention_data;
> + curlun->unit_attention_data = SS_NO_SENSE;
> + }
> +#endif
> +
> + if (!curlun) { /* Unsupported LUNs are okay */
> + common->bad_lun_okay = 1;
> + sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
> + valid = 0;
> + } else {
> + sd = curlun->sense_data;
> + valid = curlun->info_valid << 7;
> + curlun->sense_data = SS_NO_SENSE;
> + curlun->info_valid = 0;
> + }
> +
> + memset(buf, 0, 18);
> + buf[0] = valid | 0x70; /* Valid, current error */
> + buf[2] = SK(sd);
> + put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
> + buf[7] = 18 - 8; /* Additional sense length */
> + buf[12] = ASC(sd);
> + buf[13] = ASCQ(sd);
> + return 18;
> +}
> +
> +static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> + u32 lba = get_unaligned_be32(&common->cmnd[2]);
> + int pmi = common->cmnd[8];
> + u8 *buf = (u8 *) bh->buf;
> +
> + /* Check the PMI and LBA fields */
> + if (pmi > 1 || (pmi == 0 && lba != 0)) {
> + curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
> + return -EINVAL;
> + }
> +
> + put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
> + /* Max logical block */
> + put_unaligned_be32(512, &buf[4]); /* Block length */
> + return 8;
> +}
> +
> +static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> + int msf = common->cmnd[1] & 0x02;
> + u32 lba = get_unaligned_be32(&common->cmnd[2]);
> + u8 *buf = (u8 *) bh->buf;
> +
> + if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
> + curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
> + return -EINVAL;
> + }
> + if (lba >= curlun->num_sectors) {
> + curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
> + return -EINVAL;
> + }
> +
> + memset(buf, 0, 8);
> + buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
> + store_cdrom_address(&buf[4], msf, lba);
> + return 8;
> +}
> +
> +
> +static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> + int msf = common->cmnd[1] & 0x02;
> + int start_track = common->cmnd[6];
> + u8 *buf = (u8 *) bh->buf;
> +
> + if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
> + start_track > 1) {
> + curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
> + return -EINVAL;
> + }
> +
> + memset(buf, 0, 20);
> + buf[1] = (20-2); /* TOC data length */
> + buf[2] = 1; /* First track number */
> + buf[3] = 1; /* Last track number */
> + buf[5] = 0x16; /* Data track, copying allowed */
> + buf[6] = 0x01; /* Only track is number 1 */
> + store_cdrom_address(&buf[8], msf, 0);
> +
> + buf[13] = 0x16; /* Lead-out track is data */
> + buf[14] = 0xAA; /* Lead-out track number */
> + store_cdrom_address(&buf[16], msf, curlun->num_sectors);
> +
> + return 20;
> +}
> +
> +static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> + int mscmnd = common->cmnd[0];
> + u8 *buf = (u8 *) bh->buf;
> + u8 *buf0 = buf;
> + int pc, page_code;
> + int changeable_values, all_pages;
> + int valid_page = 0;
> + int len, limit;
> +
> + if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
> + curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
> + return -EINVAL;
> + }
> + pc = common->cmnd[2] >> 6;
> + page_code = common->cmnd[2] & 0x3f;
> + if (pc == 3) {
> + curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
> + return -EINVAL;
> + }
> + changeable_values = (pc == 1);
> + all_pages = (page_code == 0x3f);
> +
> + /* Write the mode parameter header. Fixed values are: default
> + * medium type, no cache control (DPOFUA), and no block descriptors.
> + * The only variable value is the WriteProtect bit. We will fill in
> + * the mode data length later. */
> + memset(buf, 0, 8);
> + if (mscmnd == SCSI_MODE_SEN6) {
> + buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
> + buf += 4;
> + limit = 255;
> + } else { /* SCSI_MODE_SEN10 */
> + buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
> + buf += 8;
> + limit = 65535; /* Should really be FSG_BUFLEN */
> + }
> +
> + /* No block descriptors */
> +
> + /* The mode pages, in numerical order. The only page we support
> + * is the Caching page. */
> + if (page_code == 0x08 || all_pages) {
> + valid_page = 1;
> + buf[0] = 0x08; /* Page code */
> + buf[1] = 10; /* Page length */
> + memset(buf+2, 0, 10); /* None of the fields are changeable */
> +
> + if (!changeable_values) {
> + buf[2] = 0x04; /* Write cache enable, */
> + /* Read cache not disabled */
> + /* No cache retention priorities */
> + put_unaligned_be16(0xffff, &buf[4]);
> + /* Don't disable prefetch */
> + /* Minimum prefetch = 0 */
> + put_unaligned_be16(0xffff, &buf[8]);
> + /* Maximum prefetch */
> + put_unaligned_be16(0xffff, &buf[10]);
> + /* Maximum prefetch ceiling */
> + }
> + buf += 12;
> + }
> +
> + /* Check that a valid page was requested and the mode data length
> + * isn't too long. */
> + len = buf - buf0;
> + if (!valid_page || len > limit) {
> + curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
> + return -EINVAL;
> + }
> +
> + /* Store the mode data length */
> + if (mscmnd == SCSI_MODE_SEN6)
> + buf0[0] = len - 1;
> + else
> + put_unaligned_be16(len - 2, buf0);
> + return len;
> +}
> +
> +
> +static int do_start_stop(struct fsg_common *common)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> +
> + if (!curlun) {
> + return -EINVAL;
> + } else if (!curlun->removable) {
> + curlun->sense_data = SS_INVALID_COMMAND;
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static int do_prevent_allow(struct fsg_common *common)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> + int prevent;
> +
> + if (!curlun->removable) {
> + curlun->sense_data = SS_INVALID_COMMAND;
> + return -EINVAL;
> + }
> +
> + prevent = common->cmnd[4] & 0x01;
> + if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
> + curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
> + return -EINVAL;
> + }
> +
> + if (curlun->prevent_medium_removal && !prevent)
> + fsg_lun_fsync_sub(curlun);
> + curlun->prevent_medium_removal = prevent;
> + return 0;
> +}
> +
> +
> +static int do_read_format_capacities(struct fsg_common *common,
> + struct fsg_buffhd *bh)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> + u8 *buf = (u8 *) bh->buf;
> +
> + buf[0] = buf[1] = buf[2] = 0;
> + buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
> + buf += 4;
> +
> + put_unaligned_be32(curlun->num_sectors, &buf[0]);
> + /* Number of blocks */
> + put_unaligned_be32(512, &buf[4]); /* Block length */
> + buf[4] = 0x02; /* Current capacity */
> + return 12;
> +}
> +
> +
> +static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> +
> + /* We don't support MODE SELECT */
> + if (curlun)
> + curlun->sense_data = SS_INVALID_COMMAND;
> + return -EINVAL;
> +}
> +
> +
> +/*-------------------------------------------------------------------------*/
> +
> +static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
> +{
> + int rc;
> +
> + rc = fsg_set_halt(fsg, fsg->bulk_in);
> + if (rc == -EAGAIN)
> + VDBG(fsg, "delayed bulk-in endpoint halt\n");
> + while (rc != 0) {
> + if (rc != -EAGAIN) {
> + WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
> + rc = 0;
> + break;
> + }
> +
> + 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 = 0; /* 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;
> + }
> + }
> + return rc;
> +}
> +
> +static int pad_with_zeros(struct fsg_dev *fsg)
> +{
> + struct fsg_buffhd *bh = fsg->common->next_buffhd_to_fill;
> + u32 nkeep = bh->inreq->length;
> + u32 nsend;
> + int rc;
> +
> + bh->state = BUF_STATE_EMPTY; /* For the first iteration */
> + fsg->common->usb_amount_left = nkeep + fsg->common->residue;
> + while (fsg->common->usb_amount_left > 0) {
> +
> + /* Wait for the next buffer to be free */
> + while (bh->state != BUF_STATE_EMPTY) {
> + rc = sleep_thread(fsg->common);
> + if (rc)
> + return rc;
> + }
> +
> + nsend = min(fsg->common->usb_amount_left, FSG_BUFLEN);
> + memset(bh->buf + nkeep, 0, nsend - nkeep);
> + bh->inreq->length = nsend;
> + bh->inreq->zero = 0;
> + start_transfer(fsg, fsg->bulk_in, bh->inreq,
> + &bh->inreq_busy, &bh->state);
> + bh = fsg->common->next_buffhd_to_fill = bh->next;
> + fsg->common->usb_amount_left -= nsend;
> + nkeep = 0;
> + }
> + return 0;
> +}
> +
> +static int throw_away_data(struct fsg_common *common)
> +{
> + struct fsg_buffhd *bh;
> + u32 amount;
> + int rc;
> +
> + for (bh = common->next_buffhd_to_drain;
> + bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
> + bh = common->next_buffhd_to_drain) {
> +
> + /* Throw away the data in a filled buffer */
> + if (bh->state == BUF_STATE_FULL) {
> + bh->state = BUF_STATE_EMPTY;
> + common->next_buffhd_to_drain = bh->next;
> +
> + /* A short packet or an error ends everything */
> + if (bh->outreq->actual != bh->outreq->length ||
> + bh->outreq->status != 0) {
> + raise_exception(common,
> + FSG_STATE_ABORT_BULK_OUT);
> + return -EPIPE;
> + }
> + continue;
> + }
> +
> + /* Try to submit another request if we need one */
> + bh = common->next_buffhd_to_fill;
> + if (bh->state == BUF_STATE_EMPTY
> + && common->usb_amount_left > 0) {
> + amount = min(common->usb_amount_left, FSG_BUFLEN);
> +
> + /* amount is always divisible by 512, hence by
> + * the bulk-out maxpacket size */
> + bh->outreq->length = amount;
> + bh->bulk_out_intended_length = amount;
> + bh->outreq->short_not_ok = 1;
> + START_TRANSFER_OR(common, bulk_out, bh->outreq,
> + &bh->outreq_busy, &bh->state)
> + /* Don't know what to do if
> + * common->fsg is NULL */
> + return -EIO;
> + common->next_buffhd_to_fill = bh->next;
> + common->usb_amount_left -= amount;
> + continue;
> + }
> +
> + /* Otherwise wait for something to happen */
> + rc = sleep_thread(common);
> + if (rc)
> + return rc;
> + }
> + return 0;
> +}
> +
> +
> +static int finish_reply(struct fsg_common *common)
> +{
> + struct fsg_buffhd *bh = common->next_buffhd_to_fill;
> + int rc = 0;
> +
> + switch (common->data_dir) {
> + case DATA_DIR_NONE:
> + break; /* Nothing to send */
> +
> + /* If we don't know whether the host wants to read or write,
> + * this must be CB or CBI with an unknown command. We 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 (!common->can_stall) {
> + /* Nothing */
> + } else if (fsg_is_set(common)) {
> + fsg_set_halt(common->fsg, common->fsg->bulk_out);
> + rc = halt_bulk_in_endpoint(common->fsg);
> + } else {
> + /* Don't know what to do if common->fsg is NULL */
> + rc = -EIO;
> + }
> + break;
> +
> + /* All but the last buffer of data must have already been sent */
> + case DATA_DIR_TO_HOST:
> + if (common->data_size == 0) {
> + /* Nothing to send */
> +
> + /* If there's no residue, simply send the last buffer */
> + } else if (common->residue == 0) {
> + bh->inreq->zero = 0;
> + START_TRANSFER_OR(common, bulk_in, bh->inreq,
> + &bh->inreq_busy, &bh->state)
> + return -EIO;
> + common->next_buffhd_to_fill = bh->next;
> +
> + /* For Bulk-only, if we're allowed to stall then send the
> + * short packet and halt the bulk-in endpoint. If we can't
> + * stall, pad out the remaining data with 0's. */
> + } else if (common->can_stall) {
> + bh->inreq->zero = 1;
> + START_TRANSFER_OR(common, bulk_in, bh->inreq,
> + &bh->inreq_busy, &bh->state)
> + /* Don't know what to do if
> + * common->fsg is NULL */
> + rc = -EIO;
> + common->next_buffhd_to_fill = bh->next;
> + if (common->fsg)
> + rc = halt_bulk_in_endpoint(common->fsg);
> + } else if (fsg_is_set(common)) {
> + rc = pad_with_zeros(common->fsg);
> + } else {
> + /* Don't know what to do if common->fsg is NULL */
> + rc = -EIO;
> + }
> + 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 (common->residue == 0) {
> + /* Nothing to receive */
> +
> + /* Did the host stop sending unexpectedly early? */
> + } else if (common->short_packet_received) {
> + raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
> + rc = -EPIPE;
> +
> + /* 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 (common->can_stall) {
> + if (fsg_is_set(common))
> + fsg_set_halt(common->fsg,
> + common->fsg->bulk_out);
> + raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
> + rc = -EPIPE;
> +#endif
> +
> + /* We can't stall. Read in the excess data and throw it
> + * all away. */
> + } else {
> + rc = throw_away_data(common);
> + }
> + break;
> + }
> + return rc;
> +}
> +
> +
> +static int send_status(struct fsg_common *common)
> +{
> + struct fsg_lun *curlun = &common->luns[common->lun];
> + struct fsg_buffhd *bh;
> + struct bulk_cs_wrap *csw;
> + int rc;
> + u8 status = US_BULK_STAT_OK;
> + u32 sd, sdinfo = 0;
> +
> + /* Wait for the next buffer to become available */
> + bh = common->next_buffhd_to_fill;
> + while (bh->state != BUF_STATE_EMPTY) {
> + rc = sleep_thread(common);
> + if (rc)
> + return rc;
> + }
> +
> + if (curlun)
> + sd = curlun->sense_data;
> + else if (common->bad_lun_okay)
> + sd = SS_NO_SENSE;
> + else
> + sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
> +
> + if (common->phase_error) {
> + DBG(common, "sending phase-error status\n");
> + status = US_BULK_STAT_PHASE;
> + sd = SS_INVALID_COMMAND;
> + } else if (sd != SS_NO_SENSE) {
> + DBG(common, "sending command-failure status\n");
> + status = US_BULK_STAT_FAIL;
> + VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
> + " info x%x\n",
> + SK(sd), ASC(sd), ASCQ(sd), sdinfo);
> + }
> +
> + /* Store and send the Bulk-only CSW */
> + csw = (void *)bh->buf;
> +
> + csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
> + csw->Tag = common->tag;
> + csw->Residue = cpu_to_le32(common->residue);
> + csw->Status = status;
> +
> + bh->inreq->length = US_BULK_CS_WRAP_LEN;
> + bh->inreq->zero = 0;
> + START_TRANSFER_OR(common, bulk_in, bh->inreq,
> + &bh->inreq_busy, &bh->state)
> + /* Don't know what to do if common->fsg is NULL */
> + return -EIO;
> +
> + common->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_common *common, int cmnd_size,
> + enum data_direction data_dir, unsigned int mask,
> + int needs_medium, const char *name)
> +{
> + int i;
> + int lun = common->cmnd[1] >> 5;
> + static const char dirletter[4] = {'u', 'o', 'i', 'n'};
> + char hdlen[20];
> + struct fsg_lun *curlun;
> +
> + hdlen[0] = 0;
> + if (common->data_dir != DATA_DIR_UNKNOWN)
> + sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
> + common->data_size);
> + VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
> + name, cmnd_size, dirletter[(int) data_dir],
> + common->data_size_from_cmnd, common->cmnd_size, hdlen);
> +
> + /* We can't reply at all until we know the correct data direction
> + * and size. */
> + if (common->data_size_from_cmnd == 0)
> + data_dir = DATA_DIR_NONE;
> + if (common->data_size < common->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. */
> + common->data_size_from_cmnd = common->data_size;
> + common->phase_error = 1;
> + }
> + common->residue = common->data_size;
> + common->usb_amount_left = common->data_size;
> +
> + /* Conflicting data directions is a phase error */
> + if (common->data_dir != data_dir
> + && common->data_size_from_cmnd > 0) {
> + common->phase_error = 1;
> + return -EINVAL;
> + }
> +
> + /* Verify the length of the command itself */
> + if (cmnd_size != common->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 <= common->cmnd_size) {
> + DBG(common, "%s is buggy! Expected length %d "
> + "but we got %d\n", name,
> + cmnd_size, common->cmnd_size);
> + cmnd_size = common->cmnd_size;
> + } else {
> + common->phase_error = 1;
> + return -EINVAL;
> + }
> + }
> +
> + /* Check that the LUN values are consistent */
> + if (common->lun != lun)
> + DBG(common, "using LUN %d from CBW, not LUN %d from CDB\n",
> + common->lun, lun);
> +
> + /* Check the LUN */
> + if (common->lun < common->nluns) {
> + curlun = &common->luns[common->lun];
> + if (common->cmnd[0] != SCSI_REQ_SENSE) {
> + curlun->sense_data = SS_NO_SENSE;
> + curlun->info_valid = 0;
> + }
> + } else {
> + curlun = NULL;
> + common->bad_lun_okay = 0;
> +
> + /* INQUIRY and REQUEST SENSE commands are explicitly allowed
> + * to use unsupported LUNs; all others may not. */
> + if (common->cmnd[0] != SCSI_INQUIRY &&
> + common->cmnd[0] != SCSI_REQ_SENSE) {
> + DBG(common, "unsupported LUN %d\n", common->lun);
> + return -EINVAL;
> + }
> + }
> +#if 0
> + /* 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 &&
> + common->cmnd[0] != SCSI_INQUIRY &&
> + common->cmnd[0] != SCSI_REQ_SENSE) {
> + curlun->sense_data = curlun->unit_attention_data;
> + curlun->unit_attention_data = SS_NO_SENSE;
> + return -EINVAL;
> + }
> +#endif
> + /* Check that only command bytes listed in the mask are non-zero */
> + common->cmnd[1] &= 0x1f; /* Mask away the LUN */
> + for (i = 1; i < cmnd_size; ++i) {
> + if (common->cmnd[i] && !(mask & (1 << i))) {
> + if (curlun)
> + curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
> + return -EINVAL;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int do_scsi_command(struct fsg_common *common)
> +{
> + struct fsg_buffhd *bh;
> + int rc;
> + int reply = -EINVAL;
> + int i;
> + static char unknown[16];
> + struct fsg_lun *curlun = &common->luns[common->lun];
> +
> + dump_cdb(common);
> +
> + /* Wait for the next buffer to become available for data or status */
> + bh = common->next_buffhd_to_fill;
> + common->next_buffhd_to_drain = bh;
> + while (bh->state != BUF_STATE_EMPTY) {
> + rc = sleep_thread(common);
> + if (rc)
> + return rc;
> + }
> + common->phase_error = 0;
> + common->short_packet_received = 0;
> +
> + down_read(&common->filesem); /* We're using the backing file */
> + switch (common->cmnd[0]) {
> +
> + case SCSI_INQUIRY:
> + common->data_size_from_cmnd = common->cmnd[4];
> + reply = check_command(common, 6, DATA_DIR_TO_HOST,
> + (1<<4), 0,
> + "INQUIRY");
> + if (reply == 0)
> + reply = do_inquiry(common, bh);
> + break;
> +
> + case SCSI_MODE_SEL6:
> + common->data_size_from_cmnd = common->cmnd[4];
> + reply = check_command(common, 6, DATA_DIR_FROM_HOST,
> + (1<<1) | (1<<4), 0,
> + "MODE SELECT(6)");
> + if (reply == 0)
> + reply = do_mode_select(common, bh);
> + break;
> +
> + case SCSI_MODE_SEL10:
> + common->data_size_from_cmnd =
> + get_unaligned_be16(&common->cmnd[7]);
> + reply = check_command(common, 10, DATA_DIR_FROM_HOST,
> + (1<<1) | (3<<7), 0,
> + "MODE SELECT(10)");
> + if (reply == 0)
> + reply = do_mode_select(common, bh);
> + break;
> +
> + case SCSI_MODE_SEN6:
> + common->data_size_from_cmnd = common->cmnd[4];
> + reply = check_command(common, 6, DATA_DIR_TO_HOST,
> + (1<<1) | (1<<2) | (1<<4), 0,
> + "MODE SENSE(6)");
> + if (reply == 0)
> + reply = do_mode_sense(common, bh);
> + break;
> +
> + case SCSI_MODE_SEN10:
> + common->data_size_from_cmnd =
> + get_unaligned_be16(&common->cmnd[7]);
> + reply = check_command(common, 10, DATA_DIR_TO_HOST,
> + (1<<1) | (1<<2) | (3<<7), 0,
> + "MODE SENSE(10)");
> + if (reply == 0)
> + reply = do_mode_sense(common, bh);
> + break;
> +
> + case SCSI_MED_REMOVL:
> + common->data_size_from_cmnd = 0;
> + reply = check_command(common, 6, DATA_DIR_NONE,
> + (1<<4), 0,
> + "PREVENT-ALLOW MEDIUM REMOVAL");
> + if (reply == 0)
> + reply = do_prevent_allow(common);
> + break;
> +
> + case SCSI_READ6:
> + i = common->cmnd[4];
> + common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
> + reply = check_command(common, 6, DATA_DIR_TO_HOST,
> + (7<<1) | (1<<4), 1,
> + "READ(6)");
> + if (reply == 0)
> + reply = do_read(common);
> + break;
> +
> + case SCSI_READ10:
> + common->data_size_from_cmnd =
> + get_unaligned_be16(&common->cmnd[7]) << 9;
> + reply = check_command(common, 10, DATA_DIR_TO_HOST,
> + (1<<1) | (0xf<<2) | (3<<7), 1,
> + "READ(10)");
> + if (reply == 0)
> + reply = do_read(common);
> + break;
> +
> + case SCSI_READ12:
> + common->data_size_from_cmnd =
> + get_unaligned_be32(&common->cmnd[6]) << 9;
> + reply = check_command(common, 12, DATA_DIR_TO_HOST,
> + (1<<1) | (0xf<<2) | (0xf<<6), 1,
> + "READ(12)");
> + if (reply == 0)
> + reply = do_read(common);
> + break;
> +
> + case SCSI_RD_CAPAC:
> + common->data_size_from_cmnd = 8;
> + reply = check_command(common, 10, DATA_DIR_TO_HOST,
> + (0xf<<2) | (1<<8), 1,
> + "READ CAPACITY");
> + if (reply == 0)
> + reply = do_read_capacity(common, bh);
> + break;
> +
> + case SCSI_RD_HEADER:
> + if (!common->luns[common->lun].cdrom)
> + goto unknown_cmnd;
> + common->data_size_from_cmnd =
> + get_unaligned_be16(&common->cmnd[7]);
> + reply = check_command(common, 10, DATA_DIR_TO_HOST,
> + (3<<7) | (0x1f<<1), 1,
> + "READ HEADER");
> + if (reply == 0)
> + reply = do_read_header(common, bh);
> + break;
> +
> + case SCSI_RD_TOC:
> + if (!common->luns[common->lun].cdrom)
> + goto unknown_cmnd;
> + common->data_size_from_cmnd =
> + get_unaligned_be16(&common->cmnd[7]);
> + reply = check_command(common, 10, DATA_DIR_TO_HOST,
> + (7<<6) | (1<<1), 1,
> + "READ TOC");
> + if (reply == 0)
> + reply = do_read_toc(common, bh);
> + break;
> +
> + case SCSI_RD_FMT_CAPAC:
> + common->data_size_from_cmnd =
> + get_unaligned_be16(&common->cmnd[7]);
> + reply = check_command(common, 10, DATA_DIR_TO_HOST,
> + (3<<7), 1,
> + "READ FORMAT CAPACITIES");
> + if (reply == 0)
> + reply = do_read_format_capacities(common, bh);
> + break;
> +
> + case SCSI_REQ_SENSE:
> + common->data_size_from_cmnd = common->cmnd[4];
> + reply = check_command(common, 6, DATA_DIR_TO_HOST,
> + (1<<4), 0,
> + "REQUEST SENSE");
> + if (reply == 0)
> + reply = do_request_sense(common, bh);
> + break;
> +
> + case SCSI_START_STP:
> + common->data_size_from_cmnd = 0;
> + reply = check_command(common, 6, DATA_DIR_NONE,
> + (1<<1) | (1<<4), 0,
> + "START-STOP UNIT");
> + if (reply == 0)
> + reply = do_start_stop(common);
> + break;
> +
> + case SCSI_SYNC_CACHE:
> + common->data_size_from_cmnd = 0;
> + reply = check_command(common, 10, DATA_DIR_NONE,
> + (0xf<<2) | (3<<7), 1,
> + "SYNCHRONIZE CACHE");
> + if (reply == 0)
> + reply = do_synchronize_cache(common);
> + break;
> +
> + case SCSI_TST_U_RDY:
> + common->data_size_from_cmnd = 0;
> + reply = check_command(common, 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 SCSI_VERIFY:
> + common->data_size_from_cmnd = 0;
> + reply = check_command(common, 10, DATA_DIR_NONE,
> + (1<<1) | (0xf<<2) | (3<<7), 1,
> + "VERIFY");
> + if (reply == 0)
> + reply = do_verify(common);
> + break;
> +
> + case SCSI_WRITE6:
> + i = common->cmnd[4];
> + common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
> + reply = check_command(common, 6, DATA_DIR_FROM_HOST,
> + (7<<1) | (1<<4), 1,
> + "WRITE(6)");
> + if (reply == 0)
> + reply = do_write(common);
> + break;
> +
> + case SCSI_WRITE10:
> + common->data_size_from_cmnd =
> + get_unaligned_be16(&common->cmnd[7]) << 9;
> + reply = check_command(common, 10, DATA_DIR_FROM_HOST,
> + (1<<1) | (0xf<<2) | (3<<7), 1,
> + "WRITE(10)");
> + if (reply == 0)
> + reply = do_write(common);
> + break;
> +
> + case SCSI_WRITE12:
> + common->data_size_from_cmnd =
> + get_unaligned_be32(&common->cmnd[6]) << 9;
> + reply = check_command(common, 12, DATA_DIR_FROM_HOST,
> + (1<<1) | (0xf<<2) | (0xf<<6), 1,
> + "WRITE(12)");
> + if (reply == 0)
> + reply = do_write(common);
> + 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 SCSI_FORMAT:
> + case SCSI_RELEASE:
> + case SCSI_RESERVE:
> + case SCSI_SEND_DIAG:
> + /* Fall through */
> +
> + default:
> +unknown_cmnd:
> + common->data_size_from_cmnd = 0;
> + sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
> + reply = check_command(common, common->cmnd_size,
> + DATA_DIR_UNKNOWN, 0xff, 0, unknown);
> + if (reply == 0) {
> + curlun->sense_data = SS_INVALID_COMMAND;
> + reply = -EINVAL;
> + }
> + break;
> + }
> + up_read(&common->filesem);
> +
> + if (reply == -EPIPE)
> + return -EPIPE;
> +
> + /* Set up the single reply buffer for finish_reply() */
> + if (reply == -EINVAL)
> + reply = 0; /* Error reply length */
> + if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
> + reply = min((u32) reply, common->data_size_from_cmnd);
> + bh->inreq->length = reply;
> + bh->state = BUF_STATE_FULL;
> + common->residue -= reply;
> + } /* Otherwise it's already set */
> +
> + return 0;
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
> +{
> + struct usb_request *req = bh->outreq;
> + struct bulk_cb_wrap *cbw = req->buf;
> + struct fsg_common *common = fsg->common;
> +
> + /* 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 != US_BULK_CB_WRAP_LEN ||
> + cbw->Signature != cpu_to_le32(
> + US_BULK_CB_SIGN)) {
> + 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 & ~US_BULK_FLAG_IN ||
> + 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 (common->can_stall) {
> + fsg_set_halt(fsg, fsg->bulk_out);
> + halt_bulk_in_endpoint(fsg);
> + }
> + return -EINVAL;
> + }
> +
> + /* Save the command for later */
> + common->cmnd_size = cbw->Length;
> + memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
> + if (cbw->Flags & US_BULK_FLAG_IN)
> + common->data_dir = DATA_DIR_TO_HOST;
> + else
> + common->data_dir = DATA_DIR_FROM_HOST;
> + common->data_size = le32_to_cpu(cbw->DataTransferLength);
> + if (common->data_size == 0)
> + common->data_dir = DATA_DIR_NONE;
> + common->lun = cbw->Lun;
> + common->tag = cbw->Tag;
> + return 0;
> +}
> +
> +
> +static int get_next_command(struct fsg_common *common)
> +{
> + struct fsg_buffhd *bh;
> + int rc = 0;
> +
> + /* Wait for the next buffer to become available */
> + bh = common->next_buffhd_to_fill;
> + while (bh->state != BUF_STATE_EMPTY) {
> + rc = sleep_thread(common);
> + if (rc)
> + return rc;
> + }
> +
> + /* Queue a request to read a Bulk-only CBW */
> + set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
> + bh->outreq->short_not_ok = 1;
> + START_TRANSFER_OR(common, bulk_out, bh->outreq,
> + &bh->outreq_busy, &bh->state)
> + /* Don't know what to do if common->fsg is NULL */
> + return -EIO;
> +
> + /* 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(common);
> + if (rc)
> + return rc;
> + }
> +
> + rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
> + bh->state = BUF_STATE_EMPTY;
> +
> + return rc;
> +}
> +
> +
> +/*-------------------------------------------------------------------------*/
> +
> +static int enable_endpoint(struct fsg_common *common, struct usb_ep *ep)
> +{
> + int rc;
> +
> + ep->driver_data = common;
> + rc = usb_ep_enable(ep);
> + if (rc)
> + ERROR(common, "can't enable %s, result %d\n", ep->name, rc);
> + return rc;
> +}
> +
> +static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
> + struct usb_request **preq)
> +{
> + *preq = usb_ep_alloc_request(ep);
> + if (*preq)
> + return 0;
> + ERROR(common, "can't allocate request for %s\n", ep->name);
> + return -ENOMEM;
> +}
> +
> +/* Reset interface setting and re-init endpoint state (toggle etc). */
> +static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
> +{
> + struct fsg_dev *fsg;
> + int i, rc = 0;
> +
> + if (common->running)
> + DBG(common, "reset interface\n");
> +
> +reset:
> + /* Deallocate the requests */
> + if (common->fsg) {
> + fsg = common->fsg;
> +
> + for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
> + struct fsg_buffhd *bh = &common->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;
> + }
> + }
> +
> + /* 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;
> + }
> +
> + common->fsg = NULL;
> + wake_up(&common->fsg_wait);
> + }
> +
> + common->running = 0;
> + if (!new_fsg || rc)
> + return rc;
> +
> + common->fsg = new_fsg;
> + fsg = common->fsg;
> +
> + /* Enable the endpoints */
> + fsg->bulk_in->desc = fsg_ep_desc(common->gadget,
> + &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
> + rc = enable_endpoint(common, fsg->bulk_in);
> + if (rc)
> + goto reset;
> + fsg->bulk_in_enabled = 1;
> +
> + fsg->bulk_out->desc = fsg_ep_desc(common->gadget,
> + &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
> + rc = enable_endpoint(common, fsg->bulk_out);
> + if (rc)
> + goto reset;
> + fsg->bulk_out_enabled = 1;
> + common->bulk_out_maxpacket = 512;
> + clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
> +
> + /* Allocate the requests */
> + for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
> + struct fsg_buffhd *bh = &common->buffhds[i];
> +
> + rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
> + if (rc)
> + goto reset;
> + rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
> + if (rc)
> + 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;
> + }
> +
> + common->running = 1;
> +
> + return rc;
> +}
> +
> +
> +/****************************** ALT CONFIGS ******************************/
> +
> +
> +static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
> +{
> + struct fsg_dev *fsg = fsg_from_func(f);
> + fsg->common->new_fsg = fsg;
> + raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
> + return 0;
> +}
> +
> +static void fsg_disable(struct usb_function *f)
> +{
> + struct fsg_dev *fsg = fsg_from_func(f);
> + fsg->common->new_fsg = NULL;
> + raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +static void handle_exception(struct fsg_common *common)
> +{
> + int i;
> + struct fsg_buffhd *bh;
> + enum fsg_state old_state;
> + struct fsg_lun *curlun;
> + unsigned int exception_req_tag;
> +
> + /* Cancel all the pending transfers */
> + if (common->fsg) {
> + for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
> + bh = &common->buffhds[i];
> + if (bh->inreq_busy)
> + usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
> + if (bh->outreq_busy)
> + usb_ep_dequeue(common->fsg->bulk_out,
> + bh->outreq);
> + }
> +
> + /* Wait until everything is idle */
> + for (;;) {
> + int num_active = 0;
> + for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
> + bh = &common->buffhds[i];
> + num_active += bh->inreq_busy + bh->outreq_busy;
> + }
> + if (num_active == 0)
> + break;
> + if (sleep_thread(common))
> + return;
> + }
> +
> + /* Clear out the controller's fifos */
> + if (common->fsg->bulk_in_enabled)
> + usb_ep_fifo_flush(common->fsg->bulk_in);
> + if (common->fsg->bulk_out_enabled)
> + usb_ep_fifo_flush(common->fsg->bulk_out);
> + }
> +
> + /* Reset the I/O buffer states and pointers, the SCSI
> + * state, and the exception. Then invoke the handler. */
> +
> + for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
> + bh = &common->buffhds[i];
> + bh->state = BUF_STATE_EMPTY;
> + }
> + common->next_buffhd_to_fill = &common->buffhds[0];
> + common->next_buffhd_to_drain = &common->buffhds[0];
> + exception_req_tag = common->exception_req_tag;
> + old_state = common->state;
> +
> + report_exception("handling", old_state);
> +
> + if (old_state == FSG_STATE_ABORT_BULK_OUT)
> + common->state = FSG_STATE_STATUS_PHASE;
> + else {
> + for (i = 0; i < common->nluns; ++i) {
> + curlun = &common->luns[i];
> + curlun->sense_data = SS_NO_SENSE;
> + curlun->info_valid = 0;
> + }
> + common->state = FSG_STATE_IDLE;
> + }
> +
> + /* Carry out any extra actions required for the exception */
> + switch (old_state) {
> + case FSG_STATE_ABORT_BULK_OUT:
> + send_status(common);
> +
> + if (common->state == FSG_STATE_STATUS_PHASE)
> + common->state = FSG_STATE_IDLE;
> + 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 (!fsg_is_set(common))
> + break;
> + if (test_and_clear_bit(IGNORE_BULK_OUT,
> + &common->fsg->atomic_bitflags))
> + usb_ep_clear_halt(common->fsg->bulk_in);
> +
> + if (common->ep0_req_tag == exception_req_tag)
> + ep0_queue(common); /* Complete the status stage */
> +
> + break;
> +
> + case FSG_STATE_CONFIG_CHANGE:
> + do_set_interface(common, common->new_fsg);
> + break;
> +
> + case FSG_STATE_EXIT:
> + case FSG_STATE_TERMINATED:
> + do_set_interface(common, NULL); /* Free resources */
> + common->state = FSG_STATE_TERMINATED; /* Stop the thread */
> + break;
> +
> + case FSG_STATE_INTERFACE_CHANGE:
> + case FSG_STATE_DISCONNECT:
> + case FSG_STATE_COMMAND_PHASE:
> + case FSG_STATE_DATA_PHASE:
> + case FSG_STATE_STATUS_PHASE:
> + case FSG_STATE_IDLE:
> + break;
> + }
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +static int fsg_main_thread(void *common_)
> +{
> + struct fsg_common *common = common_;
> + int ret = 0;
> +
> + /* The main loop */
> + while (common->state != FSG_STATE_TERMINATED) {
> + if (exception_in_progress(common)) {
> + handle_exception(common);
> + continue;
> + }
> +
> + if (!common->running) {
> + ret = sleep_thread(common);
> + if (ret)
> + break;
> + continue;
> + }
> +
> + ret = get_next_command(common);
> + if (ret)
> + continue;
> +
> + if (!exception_in_progress(common))
> + common->state = FSG_STATE_DATA_PHASE;
> +
> + if (do_scsi_command(common) || finish_reply(common))
> + continue;
> +
> + if (!exception_in_progress(common))
> + common->state = FSG_STATE_STATUS_PHASE;
> +
> + if (send_status(common))
> + continue;
> +
> + if (!exception_in_progress(common))
> + common->state = FSG_STATE_IDLE;
> + }
> +
> + if (ret && ret != -ERESTARTSYS)
> + pr_warn("%s: error %pe\n", __func__, ERR_PTR(ret));
> +
> + complete_and_exit(&common->thread_notifier, 0);
> +}
> +
> +static void fsg_common_release(struct kref *ref);
> +
> +static struct fsg_common *fsg_common_setup(void)
> +{
> + struct fsg_common *common;
> +
> + /* Allocate? */
> + common = calloc(sizeof(*common), 1);
> + if (!common)
> + return NULL;
> + common->free_storage_on_release = 1;
> +
> + init_completion(&common->thread_notifier);
> +
> + common->ops = NULL;
> + common->private_data = NULL;
> +
> + return common;
> +}
> +
> +static int fsg_common_init(struct fsg_common *common,
> + struct usb_composite_dev *cdev)
> +{
> + struct usb_gadget *gadget = cdev->gadget;
> + struct file_list_entry *fentry;
> + struct fsg_buffhd *bh;
> + struct fsg_lun *curlun;
> + int nluns, i, fd = -1, rc;
> +
> + ums_count = 0;
> +
> + common->gadget = gadget;
> + common->ep0 = gadget->ep0;
> + common->ep0req = cdev->req;
> +
> + file_list_for_each_entry(ums_files, fentry) {
> + unsigned flags = O_RDWR;
> + struct stat st;
> +
> + if (fentry->flags) {
> + pr_err("flags not supported\n");
> + return -ENOSYS;
> + }
> +
> + fd = open(fentry->filename, flags);
> + if (fd < 0) {
> + pr_err("open('%s') failed: %pe\n",
> + fentry->filename, ERR_PTR(fd));
> + return fd;
> + }
> +
> + rc = fstat(fd, &st);
> + if (rc < 0) {
> + pr_err("stat('%s') failed: %pe\n",
> + fentry->filename, ERR_PTR(rc));
> + goto close;
> + }
> +
> + if (st.st_size % SECTOR_SIZE != 0) {
> + pr_err("exporting '%s' failed: invalid block size\n",
> + fentry->filename);
> + goto close;
> + }
> +
> + ums[ums_count].fd = fd;
> + ums[ums_count].num_sectors = st.st_size / SECTOR_SIZE;
> +
> + strlcpy(ums[ums_count].name, fentry->name, sizeof(ums[ums_count].name));
> +
> + DBG(common, "LUN %d, %s sector_count %#x\n",
> + ums_count, fentry->name, ums[ums_count].num_sectors);
> +
> + ums_count++;
> + }
> +
> + /* Find out how many LUNs there should be */
> + nluns = ums_count;
> + if (nluns < 1 || nluns > FSG_MAX_LUNS) {
> + pr_warn("invalid number of LUNs: %u\n", nluns);
> + rc = -EINVAL;
> + goto close;
> + }
> +
> + /* Maybe allocate device-global string IDs, and patch descriptors */
> + if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
> + rc = usb_string_id(cdev);
> + if (unlikely(rc < 0))
> + goto error_release;
> + fsg_strings[FSG_STRING_INTERFACE].id = rc;
> + fsg_intf_desc.iInterface = rc;
> + }
> +
> + /* Create the LUNs, open their backing files, and register the
> + * LUN devices in sysfs. */
> + curlun = calloc(nluns, sizeof *curlun);
> + if (!curlun) {
> + rc = -ENOMEM;
> + goto error_release;
> + }
> + common->nluns = nluns;
> +
> + for (i = 0; i < nluns; i++) {
> + common->luns[i].removable = 1;
> +
> + rc = fsg_lun_open(&common->luns[i], ums[i].num_sectors, "");
> + if (rc)
> + goto error_luns;
> + }
> + common->lun = 0;
> +
> + /* Data buffers cyclic list */
> + bh = common->buffhds;
> +
> + i = FSG_NUM_BUFFERS;
> + goto buffhds_first_it;
> + do {
> + bh->next = bh + 1;
> + ++bh;
> +buffhds_first_it:
> + bh->inreq_busy = 0;
> + bh->outreq_busy = 0;
> + bh->buf = dma_alloc(FSG_BUFLEN);
> + if (unlikely(!bh->buf)) {
> + rc = -ENOMEM;
> + goto error_release;
> + }
> + } while (--i);
> + bh->next = common->buffhds;
> +
> + snprintf(common->inquiry_string, sizeof common->inquiry_string,
> + "%-8s%-16s%04x",
> + "Linux ",
> + "File-Store Gadget",
> + 0xffff);
> +
> + /* Some peripheral controllers are known not to be able to
> + * halt bulk endpoints correctly. If one of them is present,
> + * disable stalls.
> + */
> +
> + /* Information */
> + DBG(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
> + DBG(common, "Number of LUNs=%d\n", common->nluns);
> +
> + return 0;
> +
> +error_luns:
> + common->nluns = i + 1;
> +error_release:
> + common->state = FSG_STATE_TERMINATED; /* The thread is dead */
> + /* Call fsg_common_release() directly, ref might be not
> + * initialised */
> + fsg_common_release(&common->ref);
> +close:
> + close(fd);
> + return rc;
> +}
> +
> +static void fsg_common_release(struct kref *ref)
> +{
> + struct fsg_common *common = container_of(ref, struct fsg_common, ref);
> + struct fsg_buffhd *bh;
> + unsigned i;
> +
> + /* If the thread isn't already dead, tell it to exit now */
> + if (common->state != FSG_STATE_TERMINATED) {
> + raise_exception(common, FSG_STATE_EXIT);
> + wait_for_completion_interruptible(&common->thread_notifier);
> + free_kthread_struct(thread_task);
> + }
> +
> + bh = common->buffhds;
> + i = FSG_NUM_BUFFERS;
> +
> + do {
> + dma_free(bh->buf);
> + } while (++bh, --i);
> +
> + if (common->free_storage_on_release)
> + kfree(common);
> +}
> +
> +
> +static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
> +{
> + struct fsg_dev *fsg = fsg_from_func(f);
> + struct fsg_common *common = fsg->common;
> + int i;
> +
> + DBG(fsg, "unbind\n");
> +
> + if (fsg->common->fsg == fsg) {
> + fsg->common->new_fsg = NULL;
> + fsg->common->shutdown = true;
> + raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
> + wait_event(common->fsg_wait, common->fsg != fsg);
> + }
> +
> + for (i = 0; i < ums_count; i++)
> + close(ums[i].fd);
> +
> + usb_free_all_descriptors(&fsg->function);
> +
> + ums_files = NULL;
> +}
> +
> +static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
> +{
> + struct fsg_dev *fsg = fsg_from_func(f);
> + struct usb_gadget *gadget = c->cdev->gadget;
> + int i = -EINVAL;
> + struct usb_ep *ep;
> + struct usb_descriptor_header **hs_function = NULL;
> + struct fsg_common *common = fsg->common;
> +
> + if (!ums_files) {
> + struct f_ums_opts *opts = container_of(f->fi, struct f_ums_opts, func_inst);
> +
> + ums_files = opts->files;
> + }
> +
> + fsg->gadget = gadget;
> +
> + DBG(fsg, "bind\n");
> +
> + i = fsg_common_init(common, c->cdev);
> + if (i)
> + return i;
> +
> + thread_task = kthread_run(fsg_main_thread, common, "file-storage");
> + if (IS_ERR(thread_task))
> + return PTR_ERR(thread_task);
> +
> + /* New interface */
> + i = usb_interface_id(c, f);
> + if (i < 0)
> + return i;
> + fsg_intf_desc.bInterfaceNumber = i;
> + fsg->interface_number = i;
> +
> + /* Find all the endpoints we will use */
> + ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
> + if (!ep)
> + goto autoconf_fail;
> + ep->driver_data = common; /* 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 = common; /* claim the endpoint */
> + fsg->bulk_out = ep;
> +
> + if (gadget_is_dualspeed(gadget)) {
> + /* 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;
> + hs_function = fsg_hs_function;
> + }
> +
> + /* Copy descriptors */
> + return usb_assign_descriptors(f, fsg_fs_function, hs_function, NULL);
> +
> +autoconf_fail:
> + ERROR(fsg, "unable to autoconfigure all endpoints\n");
> + return -ENOTSUPP;
> +}
> +
> +
> +/****************************** ADD FUNCTION ******************************/
> +
> +static struct usb_gadget_strings *fsg_strings_array[] = {
> + &fsg_stringtab,
> + NULL,
> +};
> +
> +static void fsg_free(struct usb_function *f)
> +{
> + struct fsg_dev *fsg;
> +
> + fsg = container_of(f, struct fsg_dev, function);
> +
> + kfree(fsg);
> +}
> +
> +static struct usb_function *fsg_alloc(struct usb_function_instance *fi)
> +{
> + struct f_ums_opts *opts = fsg_opts_from_func_inst(fi);
> + struct fsg_common *common = opts->common;
> + struct fsg_dev *fsg;
> +
> + fsg = kzalloc(sizeof(*fsg), GFP_KERNEL);
> + if (!fsg)
> + return ERR_PTR(-ENOMEM);
> +
> + fsg->function.name = FSG_DRIVER_DESC;
> + fsg->function.strings = fsg_strings_array;
> + /* descriptors are per-instance copies */
> + fsg->function.bind = fsg_bind;
> + fsg->function.set_alt = fsg_set_alt;
> + fsg->function.setup = fsg_setup;
> + fsg->function.disable = fsg_disable;
> + fsg->function.unbind = fsg_unbind;
> + fsg->function.free_func = fsg_free;
> +
> + fsg->common = common;
> + common->fsg = fsg;
> +
> + return &fsg->function;
> +}
> +
> +static void fsg_free_instance(struct usb_function_instance *fi)
> +{
> + struct f_ums_opts *opts = fsg_opts_from_func_inst(fi);
> +
> + fsg_common_release(&opts->common->ref);
> +
> + kfree(opts);
> +}
> +
> +static struct usb_function_instance *fsg_alloc_inst(void)
> +{
> + struct f_ums_opts *opts;
> +
> + opts = kzalloc(sizeof(*opts), GFP_KERNEL);
> + if (!opts)
> + return ERR_PTR(-ENOMEM);
> +
> + opts->func_inst.free_func_inst = fsg_free_instance;
> +
> + opts->common = fsg_common_setup();
> + if (!opts->common) {
> + free(opts);
> + return ERR_PTR(-ENOMEM);
> + }
> +
> + return &opts->func_inst;
> +}
> +
> +DECLARE_USB_FUNCTION_INIT(ums, fsg_alloc_inst, fsg_alloc);
> +
> +#define STRING_MANUFACTURER_IDX 0
> +#define STRING_PRODUCT_IDX 1
> +#define STRING_DESCRIPTION_IDX 2
> +
> +static struct usb_string strings_dev[] = {
> + [STRING_MANUFACTURER_IDX].s = NULL,
> + [STRING_PRODUCT_IDX].s = NULL,
> + [STRING_DESCRIPTION_IDX].s = "USB Mass Storage",
> + { } /* end of list */
> +};
> +
> +static struct usb_function_instance *fi_fsg;
> +static struct usb_function *f_fsg;
> +
> +static struct usb_configuration config = {
> + .label = "USB Mass Storage",
> + .bConfigurationValue = 1,
> + .bmAttributes = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
> + .iConfiguration = 2,
> +};
> +
> +static int ums_driver_bind(struct usb_composite_dev *cdev)
> +{
> + struct usb_gadget *gadget = cdev->gadget;
> + int id;
> +
> + if (gadget->vendor_id && gadget->product_id) {
> + ums_dev_descriptor.idVendor = cpu_to_le16(gadget->vendor_id);
> + ums_dev_descriptor.idProduct = cpu_to_le16(gadget->product_id);
> + } else {
> + ums_dev_descriptor.idVendor = cpu_to_le16(FSG_VENDOR_ID);
> + ums_dev_descriptor.idProduct = cpu_to_le16(FSG_PRODUCT_ID);
> + }
> +
> + strings_dev[STRING_MANUFACTURER_IDX].s = gadget->manufacturer;
> + strings_dev[STRING_PRODUCT_IDX].s = gadget->productname;
> +
> + id = usb_string_id(cdev);
> + if (id < 0)
> + goto fail;
> +
> + strings_dev[STRING_MANUFACTURER_IDX].id = id;
> + ums_dev_descriptor.iManufacturer = id;
> +
> + id = usb_string_id(cdev);
> + if (id < 0)
> + goto fail;
> +
> + strings_dev[STRING_PRODUCT_IDX].id = id;
> + ums_dev_descriptor.iProduct = id;
> +
> + id = usb_add_config_only(cdev, &config);
> + if (id)
> + return id;
> +
> + fi_fsg = usb_get_function_instance("ums");
> + if (IS_ERR(fi_fsg)) {
> + id = PTR_ERR(fi_fsg);
> + goto fail;
> + }
> +
> + f_fsg = usb_get_function(fi_fsg);
> + if (IS_ERR(f_fsg)) {
> + id = PTR_ERR(f_fsg);
> + goto fail;
> + }
> +
> + id = usb_add_function(&config, f_fsg);
> + if (id)
> + goto fail;
> +
> + return 0;
> +fail:
> + return id;
> +}
> +
> +static int ums_driver_unbind(struct usb_composite_dev *cdev)
> +{
> + usb_put_function(f_fsg);
> + usb_put_function_instance(fi_fsg);
> +
> + return 0;
> +}
> +
> +static struct usb_composite_driver ums_driver = {
> + .name = "ums",
> + .dev = &ums_dev_descriptor,
> + .strings = fsg_strings_array,
> + .max_speed = USB_SPEED_HIGH,
> + .bind = ums_driver_bind,
> + .unbind = ums_driver_unbind,
> +};
> +
> +int usb_ums_register(struct f_ums_opts *opts)
> +{
> + int ret;
> +
> + if (ums_files)
> + return -EBUSY;
> +
> + ums_files = opts->files;
> +
> + ret = usb_composite_probe(&ums_driver);
> + if (ret)
> + goto out;
> +
> + while (poll())
> + ;
> +
> + usb_composite_unregister(&ums_driver);
> +out:
> + ums_files = NULL;
> +
> + return ret;
> +}
> diff --git a/drivers/usb/gadget/storage_common.c b/drivers/usb/gadget/storage_common.c
> new file mode 100644
> index 000000000000..88cd745063e4
> --- /dev/null
> +++ b/drivers/usb/gadget/storage_common.c
> @@ -0,0 +1,173 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * storage_common.c -- Common definitions for mass storage functionality
> + *
> + * Copyright (C) 2003-2008 Alan Stern
> + * Copyeight (C) 2009 Samsung Electronics
> + * Author: Michal Nazarewicz (m.nazarewicz@samsung.com)
> + *
> + * Ported to u-boot:
> + * Andrzej Pietrasiewicz <andrzej.p@samsung.com>
> + *
> + * Code refactoring & cleanup:
> + * Łukasz Majewski <l.majewski@samsung.com>
> + */
> +
> +#include "storage_common.h"
> +
> +/*
> + * This file requires the following identifiers used in USB strings to
> + * be defined (each of type pointer to char):
> + * - fsg_string_manufacturer -- name of the manufacturer
> + * - fsg_string_product -- name of the product
> + * - fsg_string_serial -- product's serial
> + * - fsg_string_config -- name of the configuration
> + * - fsg_string_interface -- name of the interface
> + * The first four are only needed when FSG_DESCRIPTORS_DEVICE_STRINGS
> + * macro is defined prior to including this file.
> + */
> +
> +/* There is only one interface. */
> +
> +struct usb_interface_descriptor fsg_intf_desc = {
> + .bLength = sizeof fsg_intf_desc,
> + .bDescriptorType = USB_DT_INTERFACE,
> +
> + .bNumEndpoints = 2, /* Adjusted during fsg_bind() */
> + .bInterfaceClass = USB_CLASS_MASS_STORAGE,
> + .bInterfaceSubClass = USB_SC_SCSI, /* Adjusted during fsg_bind() */
> + .bInterfaceProtocol = USB_PR_BULK, /* Adjusted during fsg_bind() */
> + .iInterface = FSG_STRING_INTERFACE,
> +};
> +
> +/*
> + * Three full-speed endpoint descriptors: bulk-in, bulk-out, and
> + * interrupt-in.
> + */
> +
> +struct usb_endpoint_descriptor fsg_fs_bulk_in_desc = {
> + .bLength = USB_DT_ENDPOINT_SIZE,
> + .bDescriptorType = USB_DT_ENDPOINT,
> +
> + .bEndpointAddress = USB_DIR_IN,
> + .bmAttributes = USB_ENDPOINT_XFER_BULK,
> + /* wMaxPacketSize set by autoconfiguration */
> +};
> +
> +struct usb_endpoint_descriptor fsg_fs_bulk_out_desc = {
> + .bLength = USB_DT_ENDPOINT_SIZE,
> + .bDescriptorType = USB_DT_ENDPOINT,
> +
> + .bEndpointAddress = USB_DIR_OUT,
> + .bmAttributes = USB_ENDPOINT_XFER_BULK,
> + /* wMaxPacketSize set by autoconfiguration */
> +};
> +
> +struct usb_descriptor_header *fsg_fs_function[] = {
> + (struct usb_descriptor_header *) &fsg_intf_desc,
> + (struct usb_descriptor_header *) &fsg_fs_bulk_in_desc,
> + (struct usb_descriptor_header *) &fsg_fs_bulk_out_desc,
> + NULL,
> +};
> +
> +/*
> + * USB 2.0 devices need to expose both high speed and full speed
> + * descriptors, unless they only run at full speed.
> + *
> + * That means alternate endpoint descriptors (bigger packets)
> + * and a "device qualifier" ... plus more construction options
> + * for the configuration descriptor.
> + */
> +struct usb_endpoint_descriptor fsg_hs_bulk_in_desc = {
> + .bLength = USB_DT_ENDPOINT_SIZE,
> + .bDescriptorType = USB_DT_ENDPOINT,
> +
> + /* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
> + .bmAttributes = USB_ENDPOINT_XFER_BULK,
> + .wMaxPacketSize = cpu_to_le16(512),
> +};
> +
> +struct usb_endpoint_descriptor fsg_hs_bulk_out_desc = {
> + .bLength = USB_DT_ENDPOINT_SIZE,
> + .bDescriptorType = USB_DT_ENDPOINT,
> +
> + /* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
> + .bmAttributes = USB_ENDPOINT_XFER_BULK,
> + .wMaxPacketSize = cpu_to_le16(512),
> + .bInterval = 1, /* NAK every 1 uframe */
> +};
> +
> +struct usb_descriptor_header *fsg_hs_function[] = {
> + (struct usb_descriptor_header *) &fsg_intf_desc,
> + (struct usb_descriptor_header *) &fsg_hs_bulk_in_desc,
> + (struct usb_descriptor_header *) &fsg_hs_bulk_out_desc,
> + NULL,
> +};
> +
> +/* Maxpacket and other transfer characteristics vary by speed. */
> +struct usb_endpoint_descriptor *
> +fsg_ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *fs,
> + struct usb_endpoint_descriptor *hs)
> +{
> + if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
> + return hs;
> + return fs;
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +/*
> + * If the next two routines are called while the gadget is registered,
> + * the caller must own fsg->filesem for writing.
> + */
> +
> +int fsg_lun_open(struct fsg_lun *curlun, unsigned int num_sectors,
> + const char *filename)
> +{
> + int ro;
> +
> + /* R/W if we can, R/O if we must */
> + ro = curlun->initially_ro;
> +
> + curlun->ro = ro;
> + curlun->file_length = num_sectors << 9;
> + curlun->num_sectors = num_sectors;
> + debug("open backing file: %s\n", filename);
> +
> + return 0;
> +}
> +
> +void fsg_lun_close(struct fsg_lun *curlun)
> +{
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +/*
> + * Sync the file data, don't bother with the metadata.
> + * This code was copied from fs/buffer.c:sys_fdatasync().
> + */
> +int fsg_lun_fsync_sub(struct fsg_lun *curlun)
> +{
> + return 0;
> +}
> +
> +void store_cdrom_address(u8 *dest, int msf, u32 addr)
> +{
> + if (msf) {
> + /* Convert to Minutes-Seconds-Frames */
> + addr >>= 2; /* Convert to 2048-byte frames */
> + addr += 2*75; /* Lead-in occupies 2 seconds */
> + dest[3] = addr % 75; /* Frames */
> + addr /= 75;
> + dest[2] = addr % 60; /* Seconds */
> + addr /= 60;
> + dest[1] = addr; /* Minutes */
> + dest[0] = 0; /* Reserved */
> + } else {
> + /* Absolute sector */
> + put_unaligned_be32(addr, dest);
> + }
> +}
> +
> +/*-------------------------------------------------------------------------*/
> diff --git a/drivers/usb/gadget/storage_common.h b/drivers/usb/gadget/storage_common.h
> new file mode 100644
> index 000000000000..ce07a7dac72c
> --- /dev/null
> +++ b/drivers/usb/gadget/storage_common.h
> @@ -0,0 +1,245 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +
> +#ifndef USB_STORAGE_COMMON_H
> +#define USB_STORAGE_COMMON_H
> +
> +#include <driver.h>
> +#include <usb/storage.h>
> +#include <asm/unaligned.h>
> +#include <usb/mass_storage.h>
> +
> +#ifndef DEBUG
> +#undef VERBOSE_DEBUG
> +#undef DUMP_MSGS
> +#endif /* !DEBUG */
> +
> +#define VLDBG(lun, fmt, args...) dev_vdbg(&(lun)->dev, fmt, ## args)
> +#define LDBG(lun, fmt, args...) dev_dbg (&(lun)->dev, fmt, ## args)
> +#define LERROR(lun, fmt, args...) dev_err (&(lun)->dev, fmt, ## args)
> +#define LWARN(lun, fmt, args...) dev_warn(&(lun)->dev, fmt, ## args)
> +#define LINFO(lun, fmt, args...) dev_info(&(lun)->dev, fmt, ## args)
> +
> +/*
> + * Keep those macros in sync with those in
> + * include/linux/usb/composite.h or else GCC will complain. If they
> + * are identical (the same names of arguments, white spaces in the
> + * same places) GCC will allow redefinition otherwise (even if some
> + * white space is removed or added) warning will be issued.
> + *
> + * Those macros are needed here because File Storage Gadget does not
> + * include the composite.h header. For composite gadgets those macros
> + * are redundant since composite.h is included any way.
> + *
> + * One could check whether those macros are already defined (which
> + * would indicate composite.h had been included) or not (which would
> + * indicate we were in FSG) but this is not done because a warning is
> + * desired if definitions here differ from the ones in composite.h.
> + *
> + * We want the definitions to match and be the same in File Storage
> + * Gadget as well as Mass Storage Function (and so composite gadgets
> + * using MSF). If someone changes them in composite.h it will produce
> + * a warning in this file when building MSF.
> + */
> +
> +#define DBG(d, fmt, args...) \
> + dev_dbg(&(d)->gadget->dev , fmt , ## args)
> +#define VDBG(d, fmt, args...) \
> + dev_vdbg(&(d)->gadget->dev , fmt , ## args)
> +#define ERROR(d, fmt, args...) \
> + dev_err(&(d)->gadget->dev , fmt , ## args)
> +#define WARNING(d, fmt, args...) \
> + dev_warn(&(d)->gadget->dev , fmt , ## args)
> +#define INFO(d, fmt, args...) \
> + dev_info(&(d)->gadget->dev , fmt , ## args)
> +
> +#ifdef DUMP_MSGS
> +
> +/* dump_msg(fsg, const char * label, const u8 * buf, unsigned length); */
> +# define dump_msg(fsg, label, buf, length) do { \
> + if (length < 512) { \
> + DBG(fsg, "%s, length %u:\n", label, length); \
> + print_hex_dump("", DUMP_PREFIX_OFFSET, \
> + 16, 1, buf, length, 0); \
> + } \
> +} while (0)
> +
> +# define dump_cdb(fsg) do { } while (0)
> +
> +#else
> +
> +# define dump_msg(fsg, /* const char * */ label, \
> + /* const u8 * */ buf, /* unsigned */ length) do { } while (0)
> +
> +# ifdef VERBOSE_DEBUG
> +
> +# define dump_cdb(fsg) \
> + print_hex_dump("SCSI CDB: ", DUMP_PREFIX_NONE, \
> + 16, 1, (fsg)->cmnd, (fsg)->cmnd_size, 0) \
> +
> +# else
> +
> +# define dump_cdb(fsg) do { } while (0)
> +
> +# endif /* VERBOSE_DEBUG */
> +
> +#endif /* DUMP_MSGS */
> +
> +/*
> + * Thanks to NetChip Technologies for donating this product ID.
> + *
> + * DO NOT REUSE THESE IDs with any other driver!! Ever!!
> + * Instead: allocate your own, using normal USB-IF procedures.
> + */
> +
> +#define FSG_VENDOR_ID 0x0525 /* NetChip */
> +#define FSG_PRODUCT_ID 0xa4a5 /* Linux-USB File-backed Storage Gadget */
> +
> +/* Length of a SCSI Command Data Block */
> +#define MAX_COMMAND_SIZE 16
> +
> +/* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
> +#define SS_NO_SENSE 0
> +#define SS_COMMUNICATION_FAILURE 0x040800
> +#define SS_INVALID_COMMAND 0x052000
> +#define SS_INVALID_FIELD_IN_CDB 0x052400
> +#define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE 0x052100
> +#define SS_LOGICAL_UNIT_NOT_SUPPORTED 0x052500
> +#define SS_MEDIUM_NOT_PRESENT 0x023a00
> +#define SS_MEDIUM_REMOVAL_PREVENTED 0x055302
> +#define SS_NOT_READY_TO_READY_TRANSITION 0x062800
> +#define SS_RESET_OCCURRED 0x062900
> +#define SS_SAVING_PARAMETERS_NOT_SUPPORTED 0x053900
> +#define SS_UNRECOVERED_READ_ERROR 0x031100
> +#define SS_WRITE_ERROR 0x030c02
> +#define SS_WRITE_PROTECTED 0x072700
> +
> +#define SK(x) ((u8) ((x) >> 16)) /* Sense Key byte, etc. */
> +#define ASC(x) ((u8) ((x) >> 8))
> +#define ASCQ(x) ((u8) (x))
> +
> +/*-------------------------------------------------------------------------*/
> +
> +struct fsg_lun {
> + loff_t file_length;
> + loff_t num_sectors;
> +
> + unsigned int initially_ro:1;
> + unsigned int ro:1;
> + unsigned int removable:1;
> + unsigned int cdrom:1;
> + unsigned int prevent_medium_removal:1;
> + unsigned int registered:1;
> + unsigned int info_valid:1;
> + unsigned int nofua:1;
> +
> + u32 sense_data;
> + u32 sense_data_info;
> + u32 unit_attention_data;
> +
> + struct device_d dev;
> +};
> +
> +#define fsg_lun_is_open(curlun) ((curlun)->filp != NULL)
> +
> +/* Big enough to hold our biggest descriptor */
> +#define EP0_BUFSIZE 256
> +#define DELAYED_STATUS (EP0_BUFSIZE + 999) /* An impossibly large value */
> +
> +/* Number of buffers we will use. 2 is enough for double-buffering */
> +#define FSG_NUM_BUFFERS 2
> +
> +/* Default size of buffer length. */
> +#define FSG_BUFLEN ((u32)131072)
> +
> +/* Maximal number of LUNs supported in mass storage function */
> +#define FSG_MAX_LUNS 8
> +
> +enum fsg_buffer_state {
> + BUF_STATE_EMPTY = 0,
> + BUF_STATE_FULL,
> + BUF_STATE_BUSY
> +};
> +
> +/*
> + * When FSG_BUFFHD_STATIC_BUFFER is defined when this file is included
> + * the fsg_buffhd structure's buf field will be an array of FSG_BUFLEN
> + * characters rather then a pointer to void.
> + */
> +
> +struct fsg_buffhd {
> + void *buf;
> + enum fsg_buffer_state state;
> + struct fsg_buffhd *next;
> +
> + /*
> + * The NetChip 2280 is faster, and handles some protocol faults
> + * better, if we don't submit any short bulk-out read requests.
> + * So we will record the intended request length here.
> + */
> + unsigned int bulk_out_intended_length;
> +
> + struct usb_request *inreq;
> + int inreq_busy;
> + struct usb_request *outreq;
> + int outreq_busy;
> +};
> +
> +enum fsg_state {
> + /* This one isn't used anywhere */
> + FSG_STATE_COMMAND_PHASE = -10,
> + FSG_STATE_DATA_PHASE,
> + FSG_STATE_STATUS_PHASE,
> +
> + FSG_STATE_IDLE = 0,
> + FSG_STATE_ABORT_BULK_OUT,
> + FSG_STATE_RESET,
> + FSG_STATE_INTERFACE_CHANGE,
> + FSG_STATE_CONFIG_CHANGE,
> + FSG_STATE_DISCONNECT,
> + FSG_STATE_EXIT,
> + FSG_STATE_TERMINATED
> +};
> +
> +enum data_direction {
> + DATA_DIR_UNKNOWN = 0,
> + DATA_DIR_FROM_HOST,
> + DATA_DIR_TO_HOST,
> + DATA_DIR_NONE
> +};
> +
> +/*-------------------------------------------------------------------------*/
> +
> +static inline u32 get_unaligned_be24(u8 *buf)
> +{
> + return 0xffffff & (u32) get_unaligned_be32(buf - 1);
> +}
> +
> +/*-------------------------------------------------------------------------*/
> +
> +enum {
> + FSG_STRING_INTERFACE
> +};
> +
> +/*-------------------------------------------------------------------------*/
> +
> +extern struct usb_interface_descriptor fsg_intf_desc;
> +
> +extern struct usb_endpoint_descriptor fsg_fs_bulk_in_desc;
> +extern struct usb_endpoint_descriptor fsg_fs_bulk_out_desc;
> +extern struct usb_descriptor_header *fsg_fs_function[];
> +
> +extern struct usb_endpoint_descriptor fsg_hs_bulk_in_desc;
> +extern struct usb_endpoint_descriptor fsg_hs_bulk_out_desc;
> +extern struct usb_descriptor_header *fsg_hs_function[];
> +
> +int fsg_lun_open(struct fsg_lun *curlun, unsigned int num_sectors,
> + const char *filename);
> +void fsg_lun_close(struct fsg_lun *curlun);
> +
> +struct usb_endpoint_descriptor *
> +fsg_ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *fs,
> + struct usb_endpoint_descriptor *hs);
> +int fsg_lun_fsync_sub(struct fsg_lun *curlun);
> +void store_cdrom_address(u8 *dest, int msf, u32 addr);
> +
> +#endif /* USB_STORAGE_COMMON_H */
> diff --git a/include/scsi.h b/include/scsi.h
> index e2397489ead9..7252b8ce3b62 100644
> --- a/include/scsi.h
> +++ b/include/scsi.h
> @@ -109,11 +109,14 @@
> #define SCSI_MED_REMOVL 0x1E /* Prevent/Allow medium Removal (O) */
> #define SCSI_READ6 0x08 /* Read 6-byte (MANDATORY) */
> #define SCSI_READ10 0x28 /* Read 10-byte (MANDATORY) */
> +#define SCSI_READ12 0xA8 /* Read 12-byte (O) */
> #define SCSI_RD_CAPAC 0x25 /* Read Capacity (MANDATORY) */
> +#define SCSI_RD_FMT_CAPAC 0x23
> #define SCSI_RD_DEFECT 0x37 /* Read Defect Data (O) */
> #define SCSI_READ_LONG 0x3E /* Read Long (O) */
> #define SCSI_REASS_BLK 0x07 /* Reassign Blocks (O) */
> #define SCSI_RCV_DIAG 0x1C /* Receive Diagnostic Results (O) */
> +#define SCSI_RESERVE 0x16
> #define SCSI_RELEASE 0x17 /* Release Unit (MANDATORY) */
> #define SCSI_REZERO 0x01 /* Rezero Unit (O) */
> #define SCSI_SRCH_DAT_E 0x31 /* Search Data Equal (O) */
> @@ -128,9 +131,12 @@
> #define SCSI_VERIFY 0x2F /* Verify (O) */
> #define SCSI_WRITE6 0x0A /* Write 6-Byte (MANDATORY) */
> #define SCSI_WRITE10 0x2A /* Write 10-Byte (MANDATORY) */
> +#define SCSI_WRITE12 0xAA /* Write 12-Byte (O) */
> #define SCSI_WRT_VERIFY 0x2E /* Write and Verify (O) */
> #define SCSI_WRITE_LONG 0x3F /* Write Long (O) */
> #define SCSI_WRITE_SAME 0x41 /* Write Same (O) */
> +#define SCSI_RD_TOC 0x43
> +#define SCSI_RD_HEADER 0x44
>
>
> /****************************************************************************
> @@ -165,4 +171,10 @@ void scsi_init(void);
> #define FALSE 0
> #endif
>
> +/*
> + * DEVICE TYPES
> + */
> +
> +#define TYPE_DISK 0x00
> +
> #endif /* _SCSI_H */
> diff --git a/include/usb/mass_storage.h b/include/usb/mass_storage.h
> new file mode 100644
> index 000000000000..084b3c8e8f31
> --- /dev/null
> +++ b/include/usb/mass_storage.h
> @@ -0,0 +1,28 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +/*
> + * Copyright (C) 2011 Samsung Electrnoics
> + * Lukasz Majewski <l.majewski@samsung.com>
> + */
> +
> +#ifndef __USB_MASS_STORAGE_H__
> +#define __USB_MASS_STORAGE_H__
> +
> +#include <usb/composite.h>
> +
> +/* Wait at maximum 60 seconds for cable connection */
> +#define UMS_CABLE_READY_TIMEOUT 60
> +
> +struct fsg_common;
> +
> +struct f_ums_opts {
> + struct usb_function_instance func_inst;
> + struct fsg_common *common;
> + struct file_list *files;
> + unsigned int num_sectors;
> + int fd;
> + char name[16];
> +};
> +
> +int usb_ums_register(struct f_ums_opts *);
> +
> +#endif /* __USB_MASS_STORAGE_H__ */
> diff --git a/include/usb/storage.h b/include/usb/storage.h
> new file mode 100644
> index 000000000000..e0240f864548
> --- /dev/null
> +++ b/include/usb/storage.h
> @@ -0,0 +1,87 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#ifndef __LINUX_USB_STORAGE_H
> +#define __LINUX_USB_STORAGE_H
> +
> +/*
> + * linux/usb/storage.h
> + *
> + * Copyright Matthew Wilcox for Intel Corp, 2010
> + *
> + * This file contains definitions taken from the
> + * USB Mass Storage Class Specification Overview
> + *
> + * Distributed under the terms of the GNU GPL, version two.
> + */
> +
> +/* Storage subclass codes */
> +
> +#define USB_SC_RBC 0x01 /* Typically, flash devices */
> +#define USB_SC_8020 0x02 /* CD-ROM */
> +#define USB_SC_QIC 0x03 /* QIC-157 Tapes */
> +#define USB_SC_UFI 0x04 /* Floppy */
> +#define USB_SC_8070 0x05 /* Removable media */
> +#define USB_SC_SCSI 0x06 /* Transparent */
> +#define USB_SC_LOCKABLE 0x07 /* Password-protected */
> +
> +#define USB_SC_ISD200 0xf0 /* ISD200 ATA */
> +#define USB_SC_CYP_ATACB 0xf1 /* Cypress ATACB */
> +#define USB_SC_DEVICE 0xff /* Use device's value */
> +
> +/* Storage protocol codes */
> +
> +#define USB_PR_CBI 0x00 /* Control/Bulk/Interrupt */
> +#define USB_PR_CB 0x01 /* Control/Bulk w/o interrupt */
> +#define USB_PR_BULK 0x50 /* bulk only */
> +#define USB_PR_UAS 0x62 /* USB Attached SCSI */
> +
> +#define USB_PR_USBAT 0x80 /* SCM-ATAPI bridge */
> +#define USB_PR_EUSB_SDDR09 0x81 /* SCM-SCSI bridge for SDDR-09 */
> +#define USB_PR_SDDR55 0x82 /* SDDR-55 (made up) */
> +#define USB_PR_DPCM_USB 0xf0 /* Combination CB/SDDR09 */
> +#define USB_PR_FREECOM 0xf1 /* Freecom */
> +#define USB_PR_DATAFAB 0xf2 /* Datafab chipsets */
> +#define USB_PR_JUMPSHOT 0xf3 /* Lexar Jumpshot */
> +#define USB_PR_ALAUDA 0xf4 /* Alauda chipsets */
> +#define USB_PR_KARMA 0xf5 /* Rio Karma */
> +
> +#define USB_PR_DEVICE 0xff /* Use device's value */
> +
> +/*
> + * Bulk only data structures
> + */
> +
> +/* command block wrapper */
> +struct bulk_cb_wrap {
> + __le32 Signature; /* contains 'USBC' */
> + __u32 Tag; /* unique per command id */
> + __le32 DataTransferLength; /* size of data */
> + __u8 Flags; /* direction in bit 0 */
> + __u8 Lun; /* LUN normally 0 */
> + __u8 Length; /* length of the CDB */
> + __u8 CDB[16]; /* max command */
> +};
> +
> +#define US_BULK_CB_WRAP_LEN 31
> +#define US_BULK_CB_SIGN 0x43425355 /* spells out 'USBC' */
> +#define US_BULK_FLAG_IN (1 << 7)
> +#define US_BULK_FLAG_OUT 0
> +
> +/* command status wrapper */
> +struct bulk_cs_wrap {
> + __le32 Signature; /* contains 'USBS' */
> + __u32 Tag; /* same as original command */
> + __le32 Residue; /* amount not transferred */
> + __u8 Status; /* see below */
> +};
> +
> +#define US_BULK_CS_WRAP_LEN 13
> +#define US_BULK_CS_SIGN 0x53425355 /* spells out 'USBS' */
> +#define US_BULK_STAT_OK 0
> +#define US_BULK_STAT_FAIL 1
> +#define US_BULK_STAT_PHASE 2
> +
> +/* bulk-only class specific requests */
> +#define US_BULK_RESET_REQUEST 0xff
> +#define US_BULK_GET_MAX_LUN 0xfe
> +
> +#endif
>
--
Pengutronix e.K. | |
Steuerwalder Str. 21 | http://www.pengutronix.de/ |
31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox
prev parent reply other threads:[~2021-02-17 11:48 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-15 10:27 [PATCH 0/3] usbgadget: add support for blocking " Ahmad Fatoum
2021-02-15 10:27 ` [PATCH 1/3] include: <linux/barebox-wrapper.h>: remove kthread 'replacements' Ahmad Fatoum
2021-02-15 10:27 ` [PATCH 2/3] console: unconditionally run poller_call in ctrlc() Ahmad Fatoum
2021-02-15 10:27 ` [PATCH 3/3] usbgadget: add support for USB mass storage gadget Ahmad Fatoum
2021-02-17 11:48 ` Ahmad Fatoum [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=508b4ab2-3f0b-2f34-e5bc-61141b307304@pengutronix.de \
--to=a.fatoum@pengutronix.de \
--cc=barebox@lists.infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox