/* * file_storage.c -- File-backed USB Storage Gadget, for USB development * * Copyright (C) 2003-2008 Alan Stern * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions, and the following disclaimer, * without modification. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The names of the above-listed copyright holders may not be used * to endorse or promote products derived from this software without * specific prior written permission. * * ALTERNATIVELY, this software may be distributed under the terms of the * GNU General Public License ("GPL") as published by the Free Software * Foundation, either version 2 of that License or (at your option) any * later version. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* * The File-backed Storage Gadget acts as a USB Mass Storage device, * appearing to the host as a disk drive or as a CD-ROM drive. In addition * to providing an example of a genuinely useful gadget driver for a USB * device, it also illustrates a technique of double-buffering for increased * throughput. Last but not least, it gives an easy way to probe the * behavior of the Mass Storage drivers in a USB host. * * Backing storage is provided by a regular file or a block device, specified * by the "file" module parameter. Access can be limited to read-only by * setting the optional "ro" module parameter. (For CD-ROM emulation, * access is always read-only.) The gadget will indicate that it has * removable media if the optional "removable" module parameter is set. * * The gadget supports the Control-Bulk (CB), Control-Bulk-Interrupt (CBI), * and Bulk-Only (also known as Bulk-Bulk-Bulk or BBB) transports, selected * by the optional "transport" module parameter. It also supports the * following protocols: RBC (0x01), ATAPI or SFF-8020i (0x02), QIC-157 (0c03), * UFI (0x04), SFF-8070i (0x05), and transparent SCSI (0x06), selected by * the optional "protocol" module parameter. In addition, the default * Vendor ID, Product ID, release number and serial number can be overridden. * * There is support for multiple logical units (LUNs), each of which has * its own backing file. The number of LUNs can be set using the optional * "luns" module parameter (anywhere from 1 to 8), and the corresponding * files are specified using comma-separated lists for "file" and "ro". * The default number of LUNs is taken from the number of "file" elements; * it is 1 if "file" is not given. If "removable" is not set then a backing * file must be specified for each LUN. If it is set, then an unspecified * or empty backing filename means the LUN's medium is not loaded. Ideally * each LUN would be settable independently as a disk drive or a CD-ROM * drive, but currently all LUNs have to be the same type. The CD-ROM * emulation includes a single data track and no audio tracks; hence there * need be only one backing file per LUN. * * Requirements are modest; only a bulk-in and a bulk-out endpoint are * needed (an interrupt-out endpoint is also needed for CBI). The memory * requirement amounts to two 16K buffers, size configurable by a parameter. * Support is included for both full-speed and high-speed operation. * * Note that the driver is slightly non-portable in that it assumes a * single memory/DMA buffer will be useable for bulk-in, bulk-out, and * interrupt-in endpoints. With most device controllers this isn't an * issue, but there may be some with hardware restrictions that prevent * a buffer from being used by more than one endpoint. * * Module options: * * file=filename[,filename...] * Required if "removable" is not set, names of * the files or block devices used for * backing storage * serial=HHHH... Required serial number (string of hex chars) * ro=b[,b...] Default false, booleans for read-only access * removable Default false, boolean for removable media * luns=N Default N = number of filenames, number of * LUNs to support * nofua=b[,b...] Default false, booleans for ignore FUA flag * in SCSI WRITE(10,12) commands * stall Default determined according to the type of * USB device controller (usually true), * boolean to permit the driver to halt * bulk endpoints * cdrom Default false, boolean for whether to emulate * a CD-ROM drive * transport=XXX Default BBB, transport name (CB, CBI, or BBB) * protocol=YYY Default SCSI, protocol name (RBC, 8020 or * ATAPI, QIC, UFI, 8070, or SCSI; * also 1 - 6) * vendor=0xVVVV Default 0x0525 (NetChip), USB Vendor ID * product=0xPPPP Default 0xa4a5 (FSG), USB Product ID * release=0xRRRR Override the USB release number (bcdDevice) * buflen=N Default N=16384, buffer size used (will be * rounded down to a multiple of * PAGE_CACHE_SIZE) * * If CONFIG_USB_FILE_STORAGE_TEST is not set, only the "file", "serial", "ro", * "removable", "luns", "nofua", "stall", and "cdrom" options are available; * default values are used for everything else. * * The pathnames of the backing files and the ro settings are available in * the attribute files "file", "nofua", and "ro" in the lun subdirectory of * the gadget's sysfs directory. If the "removable" option is set, writing to * these files will simulate ejecting/loading the medium (writing an empty * line means eject) and adjusting a write-enable tab. Changes to the ro * setting are not allowed when the medium is loaded or if CD-ROM emulation * is being used. * * This gadget driver is heavily based on "Gadget Zero" by David Brownell. * The driver's SCSI command interface was based on the "Information * technology - Small Computer System Interface - 2" document from * X3T9.2 Project 375D, Revision 10L, 7-SEP-93, available at * . 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 * . */ /* * Driver Design * * The FSG driver is fairly straightforward. There is a main kernel * thread that handles most of the work. Interrupt routines field * callbacks from the controller driver: bulk- and interrupt-request * completion notifications, endpoint-0 events, and disconnect events. * Completion events are passed to the main thread by wakeup calls. Many * ep0 requests are handled at interrupt time, but SetInterface, * SetConfiguration, and device reset requests are forwarded to the * thread in the form of "exceptions" using SIGUSR1 signals (since they * should interrupt any ongoing file I/O operations). * * The thread's main routine implements the standard command/data/status * parts of a SCSI interaction. It and its subroutines are full of tests * for pending signals/exceptions -- all this polling is necessary since * the kernel has no setjmp/longjmp equivalents. (Maybe this is an * indication that the driver really wants to be running in userspace.) * An important point is that so long as the thread is alive it keeps an * open reference to the backing file. This will prevent unmounting * the backing file's underlying filesystem and could cause problems * during system shutdown, for example. To prevent such problems, the * thread catches INT, TERM, and KILL signals and converts them into * an EXIT exception. * * In normal operation the main thread is started during the gadget's * fsg_bind() callback and stopped during fsg_unbind(). But it can also * exit when it receives a signal, and there's no point leaving the * gadget running when the thread is dead. So just before the thread * exits, it deregisters the gadget driver. This makes things a little * tricky: The driver is deregistered at two places, and the exiting * thread can indirectly call fsg_unbind() which in turn can tell the * thread to exit. The first problem is resolved through the use of the * REGISTERED atomic bitflag; the driver will only be deregistered once. * The second problem is resolved by having fsg_unbind() check * fsg->state; it won't try to stop the thread if the state is already * FSG_STATE_TERMINATED. * * To provide maximum throughput, the driver uses a circular pipeline of * buffer heads (struct fsg_buffhd). In principle the pipeline can be * arbitrarily long; in practice the benefits don't justify having more * than 2 stages (i.e., double buffering). But it helps to think of the * pipeline as being a long one. Each buffer head contains a bulk-in and * a bulk-out request pointer (since the buffer can be used for both * output and input -- directions always are given from the host's * point of view) as well as a pointer to the buffer and various state * variables. * * Use of the pipeline follows a simple protocol. There is a variable * (fsg->next_buffhd_to_fill) that points to the next buffer head to use. * At any time that buffer head may still be in use from an earlier * request, so each buffer head has a state variable indicating whether * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the * buffer head to be EMPTY, filling the buffer either by file I/O or by * USB I/O (during which the buffer head is BUSY), and marking the buffer * head FULL when the I/O is complete. Then the buffer will be emptied * (again possibly by USB I/O, during which it is marked BUSY) and * finally marked EMPTY again (possibly by a completion routine). * * A module parameter tells the driver to avoid stalling the bulk * endpoints wherever the transport specification allows. This is * necessary for some UDCs like the SuperH, which cannot reliably clear a * halt on a bulk endpoint. However, under certain circumstances the * Bulk-only specification requires a stall. In such cases the driver * will halt the endpoint and set a flag indicating that it should clear * the halt in software during the next device reset. Hopefully this * will permit everything to work correctly. Furthermore, although the * specification allows the bulk-out endpoint to halt when the host sends * too much data, implementing this would cause an unavoidable race. * The driver will always use the "no-stall" approach for OUT transfers. * * One subtle point concerns sending status-stage responses for ep0 * requests. Some of these requests, such as device reset, can involve * interrupting an ongoing file I/O operation, which might take an * arbitrarily long time. During that delay the host might give up on * the original ep0 request and issue a new one. When that happens the * driver should not notify the host about completion of the original * request, as the host will no longer be waiting for it. So the driver * assigns to each ep0 request a unique tag, and it keeps track of the * tag value of the request associated with a long-running exception * (device-reset, interface-change, or configuration-change). When the * exception handler is finished, the status-stage response is submitted * only if the current ep0 request tag is equal to the exception request * tag. Thus only the most recently received ep0 request will get a * status-stage response. * * Warning: This driver source file is too long. It ought to be split up * into a header file plus about 3 separate .c files, to handle the details * of the Gadget, USB Mass Storage, and SCSI protocols. */ /* #define VERBOSE_DEBUG */ /* #define DUMP_MSGS */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "gadget_chips.h" /* * Kbuild is not very cooperative with respect to linking separately * compiled library objects into one module. So for now we won't use * separate compilation ... ensuring init/exit sections work to shrink * the runtime footprint, and giving us at least some parts of what * a "gcc --combine ... part1.c part2.c part3.c ... " build would. */ #include "usbstring.c" #include "config.c" #include "epautoconf.c" /*-------------------------------------------------------------------------*/ #define DRIVER_DESC "File-backed Storage Gadget" #define DRIVER_NAME "g_file_storage" #define DRIVER_VERSION "1 September 2010" static char fsg_string_manufacturer[64]; static const char fsg_string_product[] = DRIVER_DESC; static const char fsg_string_config[] = "Self-powered"; static const char fsg_string_interface[] = "Mass Storage"; #include "storage_common.c" MODULE_DESCRIPTION(DRIVER_DESC); MODULE_AUTHOR("Alan Stern"); MODULE_LICENSE("Dual BSD/GPL"); /* * This driver assumes self-powered hardware and has no way for users to * trigger remote wakeup. It uses autoconfiguration to select endpoints * and endpoint addresses. */ /*-------------------------------------------------------------------------*/ /* Encapsulate the module parameter settings */ static struct { char *file[FSG_MAX_LUNS]; char *serial; bool ro[FSG_MAX_LUNS]; bool nofua[FSG_MAX_LUNS]; unsigned int num_filenames; unsigned int num_ros; unsigned int num_nofuas; unsigned int nluns; bool removable; bool can_stall; bool cdrom; char *transport_parm; char *protocol_parm; unsigned short vendor; unsigned short product; unsigned short release; unsigned int buflen; int transport_type; char *transport_name; int protocol_type; char *protocol_name; } mod_data = { // Default values .transport_parm = "BBB", .protocol_parm = "SCSI", .removable = 0, .can_stall = 1, .cdrom = 0, .vendor = FSG_VENDOR_ID, .product = FSG_PRODUCT_ID, .release = 0xffff, // Use controller chip type .buflen = 16384, }; module_param_array_named(file, mod_data.file, charp, &mod_data.num_filenames, S_IRUGO); MODULE_PARM_DESC(file, "names of backing files or devices"); module_param_named(serial, mod_data.serial, charp, S_IRUGO); MODULE_PARM_DESC(serial, "USB serial number"); module_param_array_named(ro, mod_data.ro, bool, &mod_data.num_ros, S_IRUGO); MODULE_PARM_DESC(ro, "true to force read-only"); module_param_array_named(nofua, mod_data.nofua, bool, &mod_data.num_nofuas, S_IRUGO); MODULE_PARM_DESC(nofua, "true to ignore SCSI WRITE(10,12) FUA bit"); module_param_named(luns, mod_data.nluns, uint, S_IRUGO); MODULE_PARM_DESC(luns, "number of LUNs"); module_param_named(removable, mod_data.removable, bool, S_IRUGO); MODULE_PARM_DESC(removable, "true to simulate removable media"); module_param_named(stall, mod_data.can_stall, bool, S_IRUGO); MODULE_PARM_DESC(stall, "false to prevent bulk stalls"); module_param_named(cdrom, mod_data.cdrom, bool, S_IRUGO); MODULE_PARM_DESC(cdrom, "true to emulate cdrom instead of disk"); /* In the non-TEST version, only the module parameters listed above * are available. */ #ifdef CONFIG_USB_FILE_STORAGE_TEST module_param_named(transport, mod_data.transport_parm, charp, S_IRUGO); MODULE_PARM_DESC(transport, "type of transport (BBB, CBI, or CB)"); module_param_named(protocol, mod_data.protocol_parm, charp, S_IRUGO); MODULE_PARM_DESC(protocol, "type of protocol (RBC, 8020, QIC, UFI, " "8070, or SCSI)"); module_param_named(vendor, mod_data.vendor, ushort, S_IRUGO); MODULE_PARM_DESC(vendor, "USB Vendor ID"); module_param_named(product, mod_data.product, ushort, S_IRUGO); MODULE_PARM_DESC(product, "USB Product ID"); module_param_named(release, mod_data.release, ushort, S_IRUGO); MODULE_PARM_DESC(release, "USB release number"); module_param_named(buflen, mod_data.buflen, uint, S_IRUGO); MODULE_PARM_DESC(buflen, "I/O buffer size"); #endif /* CONFIG_USB_FILE_STORAGE_TEST */ /* * These definitions will permit the compiler to avoid generating code for * parts of the driver that aren't used in the non-TEST version. Even gcc * can recognize when a test of a constant expression yields a dead code * path. */ #ifdef CONFIG_USB_FILE_STORAGE_TEST #define transport_is_bbb() (mod_data.transport_type == USB_PR_BULK) #define transport_is_cbi() (mod_data.transport_type == USB_PR_CBI) #define protocol_is_scsi() (mod_data.protocol_type == USB_SC_SCSI) #else #define transport_is_bbb() 1 #define transport_is_cbi() 0 #define protocol_is_scsi() 1 #endif /* CONFIG_USB_FILE_STORAGE_TEST */ /*-------------------------------------------------------------------------*/ struct fsg_dev { /* lock protects: state, all the req_busy's, and cbbuf_cmnd */ spinlock_t lock; struct usb_gadget *gadget; /* filesem protects: backing files in use */ struct rw_semaphore filesem; /* reference counting: wait until all LUNs are released */ struct kref ref; struct usb_ep *ep0; // Handy copy of gadget->ep0 struct usb_request *ep0req; // For control responses unsigned int ep0_req_tag; const char *ep0req_name; struct usb_request *intreq; // For interrupt responses int intreq_busy; struct fsg_buffhd *intr_buffhd; unsigned int bulk_out_maxpacket; enum fsg_state state; // For exception handling unsigned int exception_req_tag; u8 config, new_config; unsigned int running : 1; unsigned int bulk_in_enabled : 1; unsigned int bulk_out_enabled : 1; unsigned int intr_in_enabled : 1; unsigned int phase_error : 1; unsigned int short_packet_received : 1; unsigned int bad_lun_okay : 1; unsigned long atomic_bitflags; #define REGISTERED 0 #define IGNORE_BULK_OUT 1 #define SUSPENDED 2 struct usb_ep *bulk_in; struct usb_ep *bulk_out; struct usb_ep *intr_in; struct fsg_buffhd *next_buffhd_to_fill; struct fsg_buffhd *next_buffhd_to_drain; int thread_wakeup_needed; struct completion thread_notifier; struct task_struct *thread_task; int cmnd_size; u8 cmnd[MAX_COMMAND_SIZE]; enum data_direction data_dir; u32 data_size; u32 data_size_from_cmnd; u32 tag; unsigned int lun; u32 residue; u32 usb_amount_left; /* The CB protocol offers no way for a host to know when a command * has completed. As a result the next command may arrive early, * and we will still have to handle it. For that reason we need * a buffer to store new commands when using CB (or CBI, which * does not oblige a host to wait for command completion either). */ int cbbuf_cmnd_size; u8 cbbuf_cmnd[MAX_COMMAND_SIZE]; unsigned int nluns; struct fsg_lun *luns; struct fsg_lun *curlun; /* Must be the last entry */ struct fsg_buffhd buffhds[]; }; typedef void (*fsg_routine_t)(struct fsg_dev *); static int exception_in_progress(struct fsg_dev *fsg) { return (fsg->state > FSG_STATE_IDLE); } /* Make bulk-out requests be divisible by the maxpacket size */ static void set_bulk_out_req_length(struct fsg_dev *fsg, struct fsg_buffhd *bh, unsigned int length) { unsigned int rem; bh->bulk_out_intended_length = length; rem = length % fsg->bulk_out_maxpacket; if (rem > 0) length += fsg->bulk_out_maxpacket - rem; bh->outreq->length = length; } static struct fsg_dev *the_fsg; static struct usb_gadget_driver fsg_driver; /*-------------------------------------------------------------------------*/ static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep) { const char *name; if (ep == fsg->bulk_in) name = "bulk-in"; else if (ep == fsg->bulk_out) name = "bulk-out"; else name = ep->name; DBG(fsg, "%s set halt\n", name); return usb_ep_set_halt(ep); } /*-------------------------------------------------------------------------*/ /* * DESCRIPTORS ... most are static, but strings and (full) configuration * descriptors are built on demand. Also the (static) config and interface * descriptors are adjusted during fsg_bind(). */ /* There is only one configuration. */ #define CONFIG_VALUE 1 static struct usb_device_descriptor device_desc = { .bLength = sizeof device_desc, .bDescriptorType = USB_DT_DEVICE, .bcdUSB = cpu_to_le16(0x0200), .bDeviceClass = USB_CLASS_PER_INTERFACE, /* The next three values can be overridden by module parameters */ .idVendor = cpu_to_le16(FSG_VENDOR_ID), .idProduct = cpu_to_le16(FSG_PRODUCT_ID), .bcdDevice = cpu_to_le16(0xffff), .iManufacturer = FSG_STRING_MANUFACTURER, .iProduct = FSG_STRING_PRODUCT, .iSerialNumber = FSG_STRING_SERIAL, .bNumConfigurations = 1, }; static struct usb_config_descriptor config_desc = { .bLength = sizeof config_desc, .bDescriptorType = USB_DT_CONFIG, /* wTotalLength computed by usb_gadget_config_buf() */ .bNumInterfaces = 1, .bConfigurationValue = CONFIG_VALUE, .iConfiguration = FSG_STRING_CONFIG, .bmAttributes = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER, .bMaxPower = CONFIG_USB_GADGET_VBUS_DRAW / 2, }; static struct usb_qualifier_descriptor dev_qualifier = { .bLength = sizeof dev_qualifier, .bDescriptorType = USB_DT_DEVICE_QUALIFIER, .bcdUSB = cpu_to_le16(0x0200), .bDeviceClass = USB_CLASS_PER_INTERFACE, .bNumConfigurations = 1, }; static int populate_bos(struct fsg_dev *fsg, u8 *buf) { memcpy(buf, &fsg_bos_desc, USB_DT_BOS_SIZE); buf += USB_DT_BOS_SIZE; memcpy(buf, &fsg_ext_cap_desc, USB_DT_USB_EXT_CAP_SIZE); buf += USB_DT_USB_EXT_CAP_SIZE; memcpy(buf, &fsg_ss_cap_desc, USB_DT_USB_SS_CAP_SIZE); return USB_DT_BOS_SIZE + USB_DT_USB_SS_CAP_SIZE + USB_DT_USB_EXT_CAP_SIZE; } /* * Config descriptors must agree with the code that sets configurations * and with code managing interfaces and their altsettings. They must * also handle different speeds and other-speed requests. */ static int populate_config_buf(struct usb_gadget *gadget, u8 *buf, u8 type, unsigned index) { enum usb_device_speed speed = gadget->speed; int len; const struct usb_descriptor_header **function; if (index > 0) return -EINVAL; if (gadget_is_dualspeed(gadget) && type == USB_DT_OTHER_SPEED_CONFIG) speed = (USB_SPEED_FULL + USB_SPEED_HIGH) - speed; function = gadget_is_dualspeed(gadget) && speed == USB_SPEED_HIGH ? (const struct usb_descriptor_header **)fsg_hs_function : (const struct usb_descriptor_header **)fsg_fs_function; /* for now, don't advertise srp-only devices */ if (!gadget_is_otg(gadget)) function++; len = usb_gadget_config_buf(&config_desc, buf, EP0_BUFSIZE, function); ((struct usb_config_descriptor *) buf)->bDescriptorType = type; return len; } /*-------------------------------------------------------------------------*/ /* These routines may be called in process context or in_irq */ /* Caller must hold fsg->lock */ static void wakeup_thread(struct fsg_dev *fsg) { /* Tell the main thread that something has happened */ fsg->thread_wakeup_needed = 1; if (fsg->thread_task) wake_up_process(fsg->thread_task); } static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state) { unsigned long flags; /* Do nothing if a higher-priority exception is already in progress. * If a lower-or-equal priority exception is in progress, preempt it * and notify the main thread by sending it a signal. */ spin_lock_irqsave(&fsg->lock, flags); if (fsg->state <= new_state) { fsg->exception_req_tag = fsg->ep0_req_tag; fsg->state = new_state; if (fsg->thread_task) send_sig_info(SIGUSR1, SEND_SIG_FORCED, fsg->thread_task); } spin_unlock_irqrestore(&fsg->lock, flags); } /*-------------------------------------------------------------------------*/ /* The disconnect callback and ep0 routines. These always run in_irq, * except that ep0_queue() is called in the main thread to acknowledge * completion of various requests: set config, set interface, and * Bulk-only device reset. */ static void fsg_disconnect(struct usb_gadget *gadget) { struct fsg_dev *fsg = get_gadget_data(gadget); DBG(fsg, "disconnect or port reset\n"); raise_exception(fsg, FSG_STATE_DISCONNECT); } static int ep0_queue(struct fsg_dev *fsg) { int rc; rc = usb_ep_queue(fsg->ep0, fsg->ep0req, GFP_ATOMIC); if (rc != 0 && rc != -ESHUTDOWN) { /* We can't do much more than wait for a reset */ WARNING(fsg, "error in submission: %s --> %d\n", fsg->ep0->name, rc); } return rc; } static void ep0_complete(struct usb_ep *ep, struct usb_request *req) { struct fsg_dev *fsg = ep->driver_data; if (req->actual > 0) dump_msg(fsg, fsg->ep0req_name, req->buf, req->actual); if (req->status || req->actual != req->length) DBG(fsg, "%s --> %d, %u/%u\n", __func__, req->status, req->actual, req->length); if (req->status == -ECONNRESET) // Request was cancelled usb_ep_fifo_flush(ep); if (req->status == 0 && req->context) ((fsg_routine_t) (req->context))(fsg); } /*-------------------------------------------------------------------------*/ /* Bulk and interrupt endpoint completion handlers. * These always run in_irq. */ static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req) { struct fsg_dev *fsg = ep->driver_data; struct fsg_buffhd *bh = req->context; if (req->status || req->actual != req->length) DBG(fsg, "%s --> %d, %u/%u\n", __func__, req->status, req->actual, req->length); if (req->status == -ECONNRESET) // Request was cancelled usb_ep_fifo_flush(ep); /* Hold the lock while we update the request and buffer states */ smp_wmb(); spin_lock(&fsg->lock); bh->inreq_busy = 0; bh->state = BUF_STATE_EMPTY; wakeup_thread(fsg); spin_unlock(&fsg->lock); } static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req) { struct fsg_dev *fsg = ep->driver_data; struct fsg_buffhd *bh = req->context; dump_msg(fsg, "bulk-out", req->buf, req->actual); if (req->status || req->actual != bh->bulk_out_intended_length) DBG(fsg, "%s --> %d, %u/%u\n", __func__, req->status, req->actual, bh->bulk_out_intended_length); if (req->status == -ECONNRESET) // Request was cancelled usb_ep_fifo_flush(ep); /* Hold the lock while we update the request and buffer states */ smp_wmb(); spin_lock(&fsg->lock); bh->outreq_busy = 0; bh->state = BUF_STATE_FULL; wakeup_thread(fsg); spin_unlock(&fsg->lock); } #ifdef CONFIG_USB_FILE_STORAGE_TEST static void intr_in_complete(struct usb_ep *ep, struct usb_request *req) { struct fsg_dev *fsg = ep->driver_data; struct fsg_buffhd *bh = req->context; if (req->status || req->actual != req->length) DBG(fsg, "%s --> %d, %u/%u\n", __func__, req->status, req->actual, req->length); if (req->status == -ECONNRESET) // Request was cancelled usb_ep_fifo_flush(ep); /* Hold the lock while we update the request and buffer states */ smp_wmb(); spin_lock(&fsg->lock); fsg->intreq_busy = 0; bh->state = BUF_STATE_EMPTY; wakeup_thread(fsg); spin_unlock(&fsg->lock); } #else static void intr_in_complete(struct usb_ep *ep, struct usb_request *req) {} #endif /* CONFIG_USB_FILE_STORAGE_TEST */ /*-------------------------------------------------------------------------*/ /* Ep0 class-specific handlers. These always run in_irq. */ #ifdef CONFIG_USB_FILE_STORAGE_TEST static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh) { struct usb_request *req = fsg->ep0req; static u8 cbi_reset_cmnd[6] = { SEND_DIAGNOSTIC, 4, 0xff, 0xff, 0xff, 0xff}; /* Error in command transfer? */ if (req->status || req->length != req->actual || req->actual < 6 || req->actual > MAX_COMMAND_SIZE) { /* Not all controllers allow a protocol stall after * receiving control-out data, but we'll try anyway. */ fsg_set_halt(fsg, fsg->ep0); return; // Wait for reset } /* Is it the special reset command? */ if (req->actual >= sizeof cbi_reset_cmnd && memcmp(req->buf, cbi_reset_cmnd, sizeof cbi_reset_cmnd) == 0) { /* Raise an exception to stop the current operation * and reinitialize our state. */ DBG(fsg, "cbi reset request\n"); raise_exception(fsg, FSG_STATE_RESET); return; } VDBG(fsg, "CB[I] accept device-specific command\n"); spin_lock(&fsg->lock); /* Save the command for later */ if (fsg->cbbuf_cmnd_size) WARNING(fsg, "CB[I] overwriting previous command\n"); fsg->cbbuf_cmnd_size = req->actual; memcpy(fsg->cbbuf_cmnd, req->buf, fsg->cbbuf_cmnd_size); wakeup_thread(fsg); spin_unlock(&fsg->lock); } #else static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh) {} #endif /* CONFIG_USB_FILE_STORAGE_TEST */ static int class_setup_req(struct fsg_dev *fsg, const struct usb_ctrlrequest *ctrl) { struct usb_request *req = fsg->ep0req; int value = -EOPNOTSUPP; u16 w_index = le16_to_cpu(ctrl->wIndex); u16 w_value = le16_to_cpu(ctrl->wValue); u16 w_length = le16_to_cpu(ctrl->wLength); if (!fsg->config) return value; /* Handle Bulk-only class-specific requests */ if (transport_is_bbb()) { switch (ctrl->bRequest) { case US_BULK_RESET_REQUEST: if (ctrl->bRequestType != (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE)) break; if (w_index != 0 || w_value != 0 || w_length != 0) { value = -EDOM; break; } /* Raise an exception to stop the current operation * and reinitialize our state. */ DBG(fsg, "bulk reset request\n"); raise_exception(fsg, FSG_STATE_RESET); value = DELAYED_STATUS; break; case US_BULK_GET_MAX_LUN: if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE)) break; if (w_index != 0 || w_value != 0 || w_length != 1) { value = -EDOM; break; } VDBG(fsg, "get max LUN\n"); *(u8 *) req->buf = fsg->nluns - 1; value = 1; break; } } /* Handle CBI class-specific requests */ else { switch (ctrl->bRequest) { case USB_CBI_ADSC_REQUEST: if (ctrl->bRequestType != (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE)) break; if (w_index != 0 || w_value != 0) { value = -EDOM; break; } if (w_length > MAX_COMMAND_SIZE) { value = -EOVERFLOW; break; } value = w_length; fsg->ep0req->context = received_cbi_adsc; break; } } if (value == -EOPNOTSUPP) VDBG(fsg, "unknown class-specific control req " "%02x.%02x v%04x i%04x l%u\n", ctrl->bRequestType, ctrl->bRequest, le16_to_cpu(ctrl->wValue), w_index, w_length); return value; } /*-------------------------------------------------------------------------*/ /* Ep0 standard request handlers. These always run in_irq. */ static int standard_setup_req(struct fsg_dev *fsg, const struct usb_ctrlrequest *ctrl) { struct usb_request *req = fsg->ep0req; int value = -EOPNOTSUPP; u16 w_index = le16_to_cpu(ctrl->wIndex); u16 w_value = le16_to_cpu(ctrl->wValue); /* Usually this just stores reply data in the pre-allocated ep0 buffer, * but config change events will also reconfigure hardware. */ switch (ctrl->bRequest) { case USB_REQ_GET_DESCRIPTOR: if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE)) break; switch (w_value >> 8) { case USB_DT_DEVICE: VDBG(fsg, "get device descriptor\n"); device_desc.bMaxPacketSize0 = fsg->ep0->maxpacket; value = sizeof device_desc; memcpy(req->buf, &device_desc, value); break; case USB_DT_DEVICE_QUALIFIER: VDBG(fsg, "get device qualifier\n"); if (!gadget_is_dualspeed(fsg->gadget) || fsg->gadget->speed == USB_SPEED_SUPER) break; /* * Assume ep0 uses the same maxpacket value for both * speeds */ dev_qualifier.bMaxPacketSize0 = fsg->ep0->maxpacket; value = sizeof dev_qualifier; memcpy(req->buf, &dev_qualifier, value); break; case USB_DT_OTHER_SPEED_CONFIG: VDBG(fsg, "get other-speed config descriptor\n"); if (!gadget_is_dualspeed(fsg->gadget) || fsg->gadget->speed == USB_SPEED_SUPER) break; goto get_config; case USB_DT_CONFIG: VDBG(fsg, "get configuration descriptor\n"); get_config: value = populate_config_buf(fsg->gadget, req->buf, w_value >> 8, w_value & 0xff); break; case USB_DT_STRING: VDBG(fsg, "get string descriptor\n"); /* wIndex == language code */ value = usb_gadget_get_string(&fsg_stringtab, w_value & 0xff, req->buf); break; case USB_DT_BOS: VDBG(fsg, "get bos descriptor\n"); if (gadget_is_superspeed(fsg->gadget)) value = populate_bos(fsg, req->buf); break; } break; /* One config, two speeds */ case USB_REQ_SET_CONFIGURATION: if (ctrl->bRequestType != (USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE)) break; VDBG(fsg, "set configuration\n"); if (w_value == CONFIG_VALUE || w_value == 0) { fsg->new_config = w_value; /* Raise an exception to wipe out previous transaction * state (queued bufs, etc) and set the new config. */ raise_exception(fsg, FSG_STATE_CONFIG_CHANGE); value = DELAYED_STATUS; } break; case USB_REQ_GET_CONFIGURATION: if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE)) break; VDBG(fsg, "get configuration\n"); *(u8 *) req->buf = fsg->config; value = 1; break; case USB_REQ_SET_INTERFACE: if (ctrl->bRequestType != (USB_DIR_OUT| USB_TYPE_STANDARD | USB_RECIP_INTERFACE)) break; if (fsg->config && w_index == 0) { /* Raise an exception to wipe out previous transaction * state (queued bufs, etc) and install the new * interface altsetting. */ raise_exception(fsg, FSG_STATE_INTERFACE_CHANGE); value = DELAYED_STATUS; } break; case USB_REQ_GET_INTERFACE: if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE)) break; if (!fsg->config) break; if (w_index != 0) { value = -EDOM; break; } VDBG(fsg, "get interface\n"); *(u8 *) req->buf = 0; value = 1; break; default: VDBG(fsg, "unknown control req %02x.%02x v%04x i%04x l%u\n", ctrl->bRequestType, ctrl->bRequest, w_value, w_index, le16_to_cpu(ctrl->wLength)); } return value; } static int fsg_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) { struct fsg_dev *fsg = get_gadget_data(gadget); int rc; int w_length = le16_to_cpu(ctrl->wLength); ++fsg->ep0_req_tag; // Record arrival of a new request fsg->ep0req->context = NULL; fsg->ep0req->length = 0; dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl)); if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS) rc = class_setup_req(fsg, ctrl); else rc = standard_setup_req(fsg, ctrl); /* Respond with data/status or defer until later? */ if (rc >= 0 && rc != DELAYED_STATUS) { rc = min(rc, w_length); fsg->ep0req->length = rc; fsg->ep0req->zero = rc < w_length; fsg->ep0req_name = (ctrl->bRequestType & USB_DIR_IN ? "ep0-in" : "ep0-out"); rc = ep0_queue(fsg); } /* Device either stalls (rc < 0) or reports success */ return rc; } /*-------------------------------------------------------------------------*/ /* All the following routines run in process context */ /* Use this for bulk or interrupt transfers, not ep0 */ static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep, struct usb_request *req, int *pbusy, enum fsg_buffer_state *state) { int rc; if (ep == fsg->bulk_in) dump_msg(fsg, "bulk-in", req->buf, req->length); else if (ep == fsg->intr_in) dump_msg(fsg, "intr-in", req->buf, req->length); spin_lock_irq(&fsg->lock); *pbusy = 1; *state = BUF_STATE_BUSY; spin_unlock_irq(&fsg->lock); rc = usb_ep_queue(ep, req, GFP_KERNEL); if (rc != 0) { *pbusy = 0; *state = BUF_STATE_EMPTY; /* We can't do much more than wait for a reset */ /* Note: currently the net2280 driver fails zero-length * submissions if DMA is enabled. */ if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP && req->length == 0)) WARNING(fsg, "error in submission: %s --> %d\n", ep->name, rc); } } static int sleep_thread(struct fsg_dev *fsg) { int rc = 0; /* Wait until a signal arrives or we are woken up */ for (;;) { try_to_freeze(); set_current_state(TASK_INTERRUPTIBLE); if (signal_pending(current)) { rc = -EINTR; break; } if (fsg->thread_wakeup_needed) break; schedule(); } __set_current_state(TASK_RUNNING); fsg->thread_wakeup_needed = 0; return rc; } /*-------------------------------------------------------------------------*/ static int do_read(struct fsg_dev *fsg) { struct fsg_lun *curlun = fsg->curlun; u32 lba; struct fsg_buffhd *bh; int rc; u32 amount_left; loff_t file_offset, file_offset_tmp; unsigned int amount; ssize_t nread; /* Get the starting Logical Block Address and check that it's * not too big */ if (fsg->cmnd[0] == READ_6) lba = get_unaligned_be24(&fsg->cmnd[1]); else { lba = get_unaligned_be32(&fsg->cmnd[2]); /* We allow DPO (Disable Page Out = don't save data in the * cache) and FUA (Force Unit Access = don't read from the * cache), but we don't implement them. */ if ((fsg->cmnd[1] & ~0x18) != 0) { curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; } } if (lba >= curlun->num_sectors) { curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; return -EINVAL; } file_offset = ((loff_t) lba) << curlun->blkbits; /* Carry out the file reads */ amount_left = fsg->data_size_from_cmnd; if (unlikely(amount_left == 0)) return -EIO; // No default reply for (;;) { /* Figure out how much we need to read: * Try to read the remaining amount. * But don't read more than the buffer size. * And don't try to read past the end of the file. */ amount = min((unsigned int) amount_left, mod_data.buflen); amount = min((loff_t) amount, curlun->file_length - file_offset); /* Wait for the next buffer to become available */ bh = fsg->next_buffhd_to_fill; while (bh->state != BUF_STATE_EMPTY) { rc = sleep_thread(fsg); if (rc) return rc; } /* If we were asked to read past the end of file, * end with an empty buffer. */ if (amount == 0) { curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; curlun->sense_data_info = file_offset >> curlun->blkbits; curlun->info_valid = 1; bh->inreq->length = 0; bh->state = BUF_STATE_FULL; break; } /* Perform the read */ file_offset_tmp = file_offset; nread = vfs_read(curlun->filp, (char __user *) bh->buf, amount, &file_offset_tmp); VLDBG(curlun, "file read %u @ %llu -> %d\n", amount, (unsigned long long) file_offset, (int) nread); if (signal_pending(current)) return -EINTR; if (nread < 0) { LDBG(curlun, "error in file read: %d\n", (int) nread); nread = 0; } else if (nread < amount) { LDBG(curlun, "partial file read: %d/%u\n", (int) nread, amount); nread = round_down(nread, curlun->blksize); } file_offset += nread; amount_left -= nread; fsg->residue -= nread; /* Except at the end of the transfer, nread will be * equal to the buffer size, which is divisible by the * bulk-in maxpacket size. */ bh->inreq->length = nread; bh->state = BUF_STATE_FULL; /* If an error occurred, report it and its position */ if (nread < amount) { curlun->sense_data = SS_UNRECOVERED_READ_ERROR; curlun->sense_data_info = file_offset >> curlun->blkbits; curlun->info_valid = 1; break; } if (amount_left == 0) break; // No more left to read /* Send this buffer and go read some more */ bh->inreq->zero = 0; start_transfer(fsg, fsg->bulk_in, bh->inreq, &bh->inreq_busy, &bh->state); fsg->next_buffhd_to_fill = bh->next; } return -EIO; // No default reply } /*-------------------------------------------------------------------------*/ static int do_write(struct fsg_dev *fsg) { struct fsg_lun *curlun = fsg->curlun; u32 lba; struct fsg_buffhd *bh; int get_some_more; u32 amount_left_to_req, amount_left_to_write; loff_t usb_offset, file_offset, file_offset_tmp; unsigned int amount; ssize_t nwritten; int rc; if (curlun->ro) { curlun->sense_data = SS_WRITE_PROTECTED; return -EINVAL; } spin_lock(&curlun->filp->f_lock); curlun->filp->f_flags &= ~O_SYNC; // Default is not to wait spin_unlock(&curlun->filp->f_lock); /* Get the starting Logical Block Address and check that it's * not too big */ if (fsg->cmnd[0] == WRITE_6) lba = get_unaligned_be24(&fsg->cmnd[1]); else { lba = get_unaligned_be32(&fsg->cmnd[2]); /* We allow DPO (Disable Page Out = don't save data in the * cache) and FUA (Force Unit Access = write directly to the * medium). We don't implement DPO; we implement FUA by * performing synchronous output. */ if ((fsg->cmnd[1] & ~0x18) != 0) { curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; } /* FUA */ if (!curlun->nofua && (fsg->cmnd[1] & 0x08)) { spin_lock(&curlun->filp->f_lock); curlun->filp->f_flags |= O_DSYNC; spin_unlock(&curlun->filp->f_lock); } } if (lba >= curlun->num_sectors) { curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; return -EINVAL; } /* Carry out the file writes */ get_some_more = 1; file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits; amount_left_to_req = amount_left_to_write = fsg->data_size_from_cmnd; while (amount_left_to_write > 0) { /* Queue a request for more data from the host */ bh = fsg->next_buffhd_to_fill; if (bh->state == BUF_STATE_EMPTY && get_some_more) { /* Figure out how much we want to get: * Try to get the remaining amount, * but not more than the buffer size. */ amount = min(amount_left_to_req, mod_data.buflen); /* Beyond the end of the backing file? */ if (usb_offset >= curlun->file_length) { get_some_more = 0; curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; curlun->sense_data_info = usb_offset >> curlun->blkbits; curlun->info_valid = 1; continue; } /* Get the next buffer */ usb_offset += amount; fsg->usb_amount_left -= amount; amount_left_to_req -= amount; if (amount_left_to_req == 0) get_some_more = 0; /* Except at the end of the transfer, amount will be * equal to the buffer size, which is divisible by * the bulk-out maxpacket size. */ set_bulk_out_req_length(fsg, bh, amount); start_transfer(fsg, fsg->bulk_out, bh->outreq, &bh->outreq_busy, &bh->state); fsg->next_buffhd_to_fill = bh->next; continue; } /* Write the received data to the backing file */ bh = fsg->next_buffhd_to_drain; if (bh->state == BUF_STATE_EMPTY && !get_some_more) break; // We stopped early if (bh->state == BUF_STATE_FULL) { smp_rmb(); fsg->next_buffhd_to_drain = bh->next; bh->state = BUF_STATE_EMPTY; /* Did something go wrong with the transfer? */ if (bh->outreq->status != 0) { curlun->sense_data = SS_COMMUNICATION_FAILURE; curlun->sense_data_info = file_offset >> curlun->blkbits; curlun->info_valid = 1; break; } amount = bh->outreq->actual; if (curlun->file_length - file_offset < amount) { LERROR(curlun, "write %u @ %llu beyond end %llu\n", amount, (unsigned long long) file_offset, (unsigned long long) curlun->file_length); amount = curlun->file_length - file_offset; } /* Don't accept excess data. The spec doesn't say * what to do in this case. We'll ignore the error. */ amount = min(amount, bh->bulk_out_intended_length); /* Don't write a partial block */ amount = round_down(amount, curlun->blksize); if (amount == 0) goto empty_write; /* Perform the write */ file_offset_tmp = file_offset; nwritten = vfs_write(curlun->filp, (char __user *) bh->buf, amount, &file_offset_tmp); VLDBG(curlun, "file write %u @ %llu -> %d\n", amount, (unsigned long long) file_offset, (int) nwritten); if (signal_pending(current)) return -EINTR; // Interrupted! if (nwritten < 0) { LDBG(curlun, "error in file write: %d\n", (int) nwritten); nwritten = 0; } else if (nwritten < amount) { LDBG(curlun, "partial file write: %d/%u\n", (int) nwritten, amount); nwritten = round_down(nwritten, curlun->blksize); } file_offset += nwritten; amount_left_to_write -= nwritten; fsg->residue -= nwritten; /* If an error occurred, report it and its position */ if (nwritten < amount) { curlun->sense_data = SS_WRITE_ERROR; curlun->sense_data_info = file_offset >> curlun->blkbits; curlun->info_valid = 1; break; } empty_write: /* Did the host decide to stop early? */ if (bh->outreq->actual < bh->bulk_out_intended_length) { fsg->short_packet_received = 1; break; } continue; } /* Wait for something to happen */ rc = sleep_thread(fsg); if (rc) return rc; } return -EIO; // No default reply } /*-------------------------------------------------------------------------*/ static int do_synchronize_cache(struct fsg_dev *fsg) { struct fsg_lun *curlun = fsg->curlun; int rc; /* We ignore the requested LBA and write out all file's * dirty data buffers. */ rc = fsg_lun_fsync_sub(curlun); if (rc) curlun->sense_data = SS_WRITE_ERROR; return 0; } /*-------------------------------------------------------------------------*/ static void invalidate_sub(struct fsg_lun *curlun) { struct file *filp = curlun->filp; struct inode *inode = filp->f_path.dentry->d_inode; unsigned long rc; rc = invalidate_mapping_pages(inode->i_mapping, 0, -1); VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc); } static int do_verify(struct fsg_dev *fsg) { struct fsg_lun *curlun = fsg->curlun; u32 lba; u32 verification_length; struct fsg_buffhd *bh = fsg->next_buffhd_to_fill; loff_t file_offset, file_offset_tmp; u32 amount_left; unsigned int amount; ssize_t nread; /* Get the starting Logical Block Address and check that it's * not too big */ lba = get_unaligned_be32(&fsg->cmnd[2]); if (lba >= curlun->num_sectors) { curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; return -EINVAL; } /* We allow DPO (Disable Page Out = don't save data in the * cache) but we don't implement it. */ if ((fsg->cmnd[1] & ~0x10) != 0) { curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; } verification_length = get_unaligned_be16(&fsg->cmnd[7]); if (unlikely(verification_length == 0)) return -EIO; // No default reply /* Prepare to carry out the file verify */ amount_left = verification_length << curlun->blkbits; file_offset = ((loff_t) lba) << curlun->blkbits; /* Write out all the dirty buffers before invalidating them */ fsg_lun_fsync_sub(curlun); if (signal_pending(current)) return -EINTR; invalidate_sub(curlun); if (signal_pending(current)) return -EINTR; /* Just try to read the requested blocks */ while (amount_left > 0) { /* Figure out how much we need to read: * Try to read the remaining amount, but not more than * the buffer size. * And don't try to read past the end of the file. */ amount = min((unsigned int) amount_left, mod_data.buflen); amount = min((loff_t) amount, curlun->file_length - file_offset); if (amount == 0) { curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; curlun->sense_data_info = file_offset >> curlun->blkbits; curlun->info_valid = 1; break; } /* Perform the read */ file_offset_tmp = file_offset; nread = vfs_read(curlun->filp, (char __user *) bh->buf, amount, &file_offset_tmp); VLDBG(curlun, "file read %u @ %llu -> %d\n", amount, (unsigned long long) file_offset, (int) nread); if (signal_pending(current)) return -EINTR; if (nread < 0) { LDBG(curlun, "error in file verify: %d\n", (int) nread); nread = 0; } else if (nread < amount) { LDBG(curlun, "partial file verify: %d/%u\n", (int) nread, amount); nread = round_down(nread, curlun->blksize); } if (nread == 0) { curlun->sense_data = SS_UNRECOVERED_READ_ERROR; curlun->sense_data_info = file_offset >> curlun->blkbits; curlun->info_valid = 1; break; } file_offset += nread; amount_left -= nread; } return 0; } /*-------------------------------------------------------------------------*/ static int do_inquiry(struct fsg_dev *fsg, struct fsg_buffhd *bh) { u8 *buf = (u8 *) bh->buf; static char vendor_id[] = "Linux "; static char product_disk_id[] = "File-Stor Gadget"; static char product_cdrom_id[] = "File-CD Gadget "; if (!fsg->curlun) { // Unsupported LUNs are okay fsg->bad_lun_okay = 1; memset(buf, 0, 36); buf[0] = 0x7f; // Unsupported, no device-type buf[4] = 31; // Additional length return 36; } memset(buf, 0, 8); buf[0] = (mod_data.cdrom ? TYPE_ROM : TYPE_DISK); if (mod_data.removable) buf[1] = 0x80; buf[2] = 2; // ANSI SCSI level 2 buf[3] = 2; // SCSI-2 INQUIRY data format buf[4] = 31; // Additional length // No special options sprintf(buf + 8, "%-8s%-16s%04x", vendor_id, (mod_data.cdrom ? product_cdrom_id : product_disk_id), mod_data.release); return 36; } static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh) { struct fsg_lun *curlun = fsg->curlun; u8 *buf = (u8 *) bh->buf; u32 sd, sdinfo; int valid; /* * From the SCSI-2 spec., section 7.9 (Unit attention condition): * * If a REQUEST SENSE command is received from an initiator * with a pending unit attention condition (before the target * generates the contingent allegiance condition), then the * target shall either: * a) report any pending sense data and preserve the unit * attention condition on the logical unit, or, * b) report the unit attention condition, may discard any * pending sense data, and clear the unit attention * condition on the logical unit for that initiator. * * FSG normally uses option a); enable this code to use option b). */ #if 0 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) { curlun->sense_data = curlun->unit_attention_data; curlun->unit_attention_data = SS_NO_SENSE; } #endif if (!curlun) { // Unsupported LUNs are okay fsg->bad_lun_okay = 1; sd = SS_LOGICAL_UNIT_NOT_SUPPORTED; sdinfo = 0; valid = 0; } else { sd = curlun->sense_data; sdinfo = curlun->sense_data_info; valid = curlun->info_valid << 7; curlun->sense_data = SS_NO_SENSE; curlun->sense_data_info = 0; curlun->info_valid = 0; } memset(buf, 0, 18); buf[0] = valid | 0x70; // Valid, current error buf[2] = SK(sd); put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */ buf[7] = 18 - 8; // Additional sense length buf[12] = ASC(sd); buf[13] = ASCQ(sd); return 18; } static int do_read_capacity(struct fsg_dev *fsg, struct fsg_buffhd *bh) { struct fsg_lun *curlun = fsg->curlun; u32 lba = get_unaligned_be32(&fsg->cmnd[2]); int pmi = fsg->cmnd[8]; u8 *buf = (u8 *) bh->buf; /* Check the PMI and LBA fields */ if (pmi > 1 || (pmi == 0 && lba != 0)) { curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; } put_unaligned_be32(curlun->num_sectors - 1, &buf[0]); /* Max logical block */ put_unaligned_be32(curlun->blksize, &buf[4]); /* Block length */ return 8; } static int do_read_header(struct fsg_dev *fsg, struct fsg_buffhd *bh) { struct fsg_lun *curlun = fsg->curlun; int msf = fsg->cmnd[1] & 0x02; u32 lba = get_unaligned_be32(&fsg->cmnd[2]); u8 *buf = (u8 *) bh->buf; if ((fsg->cmnd[1] & ~0x02) != 0) { /* Mask away MSF */ curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; } if (lba >= curlun->num_sectors) { curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; return -EINVAL; } memset(buf, 0, 8); buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */ store_cdrom_address(&buf[4], msf, lba); return 8; } static int do_read_toc(struct fsg_dev *fsg, struct fsg_buffhd *bh) { struct fsg_lun *curlun = fsg->curlun; int msf = fsg->cmnd[1] & 0x02; int start_track = fsg->cmnd[6]; u8 *buf = (u8 *) bh->buf; if ((fsg->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */ start_track > 1) { curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; } memset(buf, 0, 20); buf[1] = (20-2); /* TOC data length */ buf[2] = 1; /* First track number */ buf[3] = 1; /* Last track number */ buf[5] = 0x16; /* Data track, copying allowed */ buf[6] = 0x01; /* Only track is number 1 */ store_cdrom_address(&buf[8], msf, 0); buf[13] = 0x16; /* Lead-out track is data */ buf[14] = 0xAA; /* Lead-out track number */ store_cdrom_address(&buf[16], msf, curlun->num_sectors); return 20; } static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh) { struct fsg_lun *curlun = fsg->curlun; int mscmnd = fsg->cmnd[0]; u8 *buf = (u8 *) bh->buf; u8 *buf0 = buf; int pc, page_code; int changeable_values, all_pages; int valid_page = 0; int len, limit; if ((fsg->cmnd[1] & ~0x08) != 0) { // Mask away DBD curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; } pc = fsg->cmnd[2] >> 6; page_code = fsg->cmnd[2] & 0x3f; if (pc == 3) { curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED; return -EINVAL; } changeable_values = (pc == 1); all_pages = (page_code == 0x3f); /* Write the mode parameter header. Fixed values are: default * medium type, no cache control (DPOFUA), and no block descriptors. * The only variable value is the WriteProtect bit. We will fill in * the mode data length later. */ memset(buf, 0, 8); if (mscmnd == MODE_SENSE) { buf[2] = (curlun->ro ? 0x80 : 0x00); // WP, DPOFUA buf += 4; limit = 255; } else { // MODE_SENSE_10 buf[3] = (curlun->ro ? 0x80 : 0x00); // WP, DPOFUA buf += 8; limit = 65535; // Should really be mod_data.buflen } /* No block descriptors */ /* The mode pages, in numerical order. The only page we support * is the Caching page. */ if (page_code == 0x08 || all_pages) { valid_page = 1; buf[0] = 0x08; // Page code buf[1] = 10; // Page length memset(buf+2, 0, 10); // None of the fields are changeable if (!changeable_values) { buf[2] = 0x04; // Write cache enable, // Read cache not disabled // No cache retention priorities put_unaligned_be16(0xffff, &buf[4]); /* Don't disable prefetch */ /* Minimum prefetch = 0 */ put_unaligned_be16(0xffff, &buf[8]); /* Maximum prefetch */ put_unaligned_be16(0xffff, &buf[10]); /* Maximum prefetch ceiling */ } buf += 12; } /* Check that a valid page was requested and the mode data length * isn't too long. */ len = buf - buf0; if (!valid_page || len > limit) { curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; } /* Store the mode data length */ if (mscmnd == MODE_SENSE) buf0[0] = len - 1; else put_unaligned_be16(len - 2, buf0); return len; } static int do_start_stop(struct fsg_dev *fsg) { struct fsg_lun *curlun = fsg->curlun; int loej, start; if (!mod_data.removable) { curlun->sense_data = SS_INVALID_COMMAND; return -EINVAL; } // int immed = fsg->cmnd[1] & 0x01; loej = fsg->cmnd[4] & 0x02; start = fsg->cmnd[4] & 0x01; #ifdef CONFIG_USB_FILE_STORAGE_TEST if ((fsg->cmnd[1] & ~0x01) != 0 || // Mask away Immed (fsg->cmnd[4] & ~0x03) != 0) { // Mask LoEj, Start curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; } if (!start) { /* Are we allowed to unload the media? */ if (curlun->prevent_medium_removal) { LDBG(curlun, "unload attempt prevented\n"); curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED; return -EINVAL; } if (loej) { // Simulate an unload/eject up_read(&fsg->filesem); down_write(&fsg->filesem); fsg_lun_close(curlun); up_write(&fsg->filesem); down_read(&fsg->filesem); } } else { /* Our emulation doesn't support mounting; the medium is * available for use as soon as it is loaded. */ if (!fsg_lun_is_open(curlun)) { curlun->sense_data = SS_MEDIUM_NOT_PRESENT; return -EINVAL; } } #endif return 0; } static int do_prevent_allow(struct fsg_dev *fsg) { struct fsg_lun *curlun = fsg->curlun; int prevent; if (!mod_data.removable) { curlun->sense_data = SS_INVALID_COMMAND; return -EINVAL; } prevent = fsg->cmnd[4] & 0x01; if ((fsg->cmnd[4] & ~0x01) != 0) { // Mask away Prevent curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; } if (curlun->prevent_medium_removal && !prevent) fsg_lun_fsync_sub(curlun); curlun->prevent_medium_removal = prevent; return 0; } static int do_read_format_capacities(struct fsg_dev *fsg, struct fsg_buffhd *bh) { struct fsg_lun *curlun = fsg->curlun; u8 *buf = (u8 *) bh->buf; buf[0] = buf[1] = buf[2] = 0; buf[3] = 8; // Only the Current/Maximum Capacity Descriptor buf += 4; put_unaligned_be32(curlun->num_sectors, &buf[0]); /* Number of blocks */ put_unaligned_be32(curlun->blksize, &buf[4]); /* Block length */ buf[4] = 0x02; /* Current capacity */ return 12; } static int do_mode_select(struct fsg_dev *fsg, struct fsg_buffhd *bh) { struct fsg_lun *curlun = fsg->curlun; /* We don't support MODE SELECT */ curlun->sense_data = SS_INVALID_COMMAND; return -EINVAL; } /*-------------------------------------------------------------------------*/ static int halt_bulk_in_endpoint(struct fsg_dev *fsg) { int rc; rc = fsg_set_halt(fsg, fsg->bulk_in); if (rc == -EAGAIN) VDBG(fsg, "delayed bulk-in endpoint halt\n"); while (rc != 0) { if (rc != -EAGAIN) { WARNING(fsg, "usb_ep_set_halt -> %d\n", rc); rc = 0; break; } /* Wait for a short time and then try again */ if (msleep_interruptible(100) != 0) return -EINTR; rc = usb_ep_set_halt(fsg->bulk_in); } return rc; } static int wedge_bulk_in_endpoint(struct fsg_dev *fsg) { int rc; DBG(fsg, "bulk-in set wedge\n"); rc = usb_ep_set_wedge(fsg->bulk_in); if (rc == -EAGAIN) VDBG(fsg, "delayed bulk-in endpoint wedge\n"); while (rc != 0) { if (rc != -EAGAIN) { WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc); rc = 0; break; } /* Wait for a short time and then try again */ if (msleep_interruptible(100) != 0) return -EINTR; rc = usb_ep_set_wedge(fsg->bulk_in); } return rc; } static int throw_away_data(struct fsg_dev *fsg) { struct fsg_buffhd *bh; u32 amount; int rc; while ((bh = fsg->next_buffhd_to_drain)->state != BUF_STATE_EMPTY || fsg->usb_amount_left > 0) { /* Throw away the data in a filled buffer */ if (bh->state == BUF_STATE_FULL) { smp_rmb(); bh->state = BUF_STATE_EMPTY; fsg->next_buffhd_to_drain = bh->next; /* A short packet or an error ends everything */ if (bh->outreq->actual < bh->bulk_out_intended_length || bh->outreq->status != 0) { raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT); return -EINTR; } continue; } /* Try to submit another request if we need one */ bh = fsg->next_buffhd_to_fill; if (bh->state == BUF_STATE_EMPTY && fsg->usb_amount_left > 0) { amount = min(fsg->usb_amount_left, (u32) mod_data.buflen); /* Except at the end of the transfer, amount will be * equal to the buffer size, which is divisible by * the bulk-out maxpacket size. */ set_bulk_out_req_length(fsg, bh, amount); start_transfer(fsg, fsg->bulk_out, bh->outreq, &bh->outreq_busy, &bh->state); fsg->next_buffhd_to_fill = bh->next; fsg->usb_amount_left -= amount; continue; } /* Otherwise wait for something to happen */ rc = sleep_thread(fsg); if (rc) return rc; } return 0; } static int finish_reply(struct fsg_dev *fsg) { struct fsg_buffhd *bh = fsg->next_buffhd_to_fill; int rc = 0; switch (fsg->data_dir) { case DATA_DIR_NONE: break; // Nothing to send /* If we don't know whether the host wants to read or write, * this must be CB or CBI with an unknown command. We mustn't * try to send or receive any data. So stall both bulk pipes * if we can and wait for a reset. */ case DATA_DIR_UNKNOWN: if (mod_data.can_stall) { fsg_set_halt(fsg, fsg->bulk_out); rc = halt_bulk_in_endpoint(fsg); } break; /* All but the last buffer of data must have already been sent */ case DATA_DIR_TO_HOST: if (fsg->data_size == 0) ; // Nothing to send /* If there's no residue, simply send the last buffer */ else if (fsg->residue == 0) { bh->inreq->zero = 0; start_transfer(fsg, fsg->bulk_in, bh->inreq, &bh->inreq_busy, &bh->state); fsg->next_buffhd_to_fill = bh->next; } /* There is a residue. For CB and CBI, simply mark the end * of the data with a short packet. However, if we are * allowed to stall, there was no data at all (residue == * data_size), and the command failed (invalid LUN or * sense data is set), then halt the bulk-in endpoint * instead. */ else if (!transport_is_bbb()) { if (mod_data.can_stall && fsg->residue == fsg->data_size && (!fsg->curlun || fsg->curlun->sense_data != SS_NO_SENSE)) { bh->state = BUF_STATE_EMPTY; rc = halt_bulk_in_endpoint(fsg); } else { bh->inreq->zero = 1; start_transfer(fsg, fsg->bulk_in, bh->inreq, &bh->inreq_busy, &bh->state); fsg->next_buffhd_to_fill = bh->next; } } /* * For Bulk-only, mark the end of the data with a short * packet. If we are allowed to stall, halt the bulk-in * endpoint. (Note: This violates the Bulk-Only Transport * specification, which requires us to pad the data if we * don't halt the endpoint. Presumably nobody will mind.) */ else { bh->inreq->zero = 1; start_transfer(fsg, fsg->bulk_in, bh->inreq, &bh->inreq_busy, &bh->state); fsg->next_buffhd_to_fill = bh->next; if (mod_data.can_stall) rc = halt_bulk_in_endpoint(fsg); } break; /* We have processed all we want from the data the host has sent. * There may still be outstanding bulk-out requests. */ case DATA_DIR_FROM_HOST: if (fsg->residue == 0) ; // Nothing to receive /* Did the host stop sending unexpectedly early? */ else if (fsg->short_packet_received) { raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT); rc = -EINTR; } /* We haven't processed all the incoming data. Even though * we may be allowed to stall, doing so would cause a race. * The controller may already have ACK'ed all the remaining * bulk-out packets, in which case the host wouldn't see a * STALL. Not realizing the endpoint was halted, it wouldn't * clear the halt -- leading to problems later on. */ #if 0 else if (mod_data.can_stall) { fsg_set_halt(fsg, fsg->bulk_out); raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT); rc = -EINTR; } #endif /* We can't stall. Read in the excess data and throw it * all away. */ else rc = throw_away_data(fsg); break; } return rc; } static int send_status(struct fsg_dev *fsg) { struct fsg_lun *curlun = fsg->curlun; struct fsg_buffhd *bh; int rc; u8 status = US_BULK_STAT_OK; u32 sd, sdinfo = 0; /* Wait for the next buffer to become available */ bh = fsg->next_buffhd_to_fill; while (bh->state != BUF_STATE_EMPTY) { rc = sleep_thread(fsg); if (rc) return rc; } if (curlun) { sd = curlun->sense_data; sdinfo = curlun->sense_data_info; } else if (fsg->bad_lun_okay) sd = SS_NO_SENSE; else sd = SS_LOGICAL_UNIT_NOT_SUPPORTED; if (fsg->phase_error) { DBG(fsg, "sending phase-error status\n"); status = US_BULK_STAT_PHASE; sd = SS_INVALID_COMMAND; } else if (sd != SS_NO_SENSE) { DBG(fsg, "sending command-failure status\n"); status = US_BULK_STAT_FAIL; VDBG(fsg, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;" " info x%x\n", SK(sd), ASC(sd), ASCQ(sd), sdinfo); } if (transport_is_bbb()) { struct bulk_cs_wrap *csw = bh->buf; /* Store and send the Bulk-only CSW */ csw->Signature = cpu_to_le32(US_BULK_CS_SIGN); csw->Tag = fsg->tag; csw->Residue = cpu_to_le32(fsg->resi