diff options
Diffstat (limited to 'drivers/usb/gadget/function/f_mass_storage.c')
| -rw-r--r-- | drivers/usb/gadget/function/f_mass_storage.c | 3668 |
1 files changed, 3668 insertions, 0 deletions
diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c new file mode 100644 index 000000000000..b96393908860 --- /dev/null +++ b/drivers/usb/gadget/function/f_mass_storage.c @@ -0,0 +1,3668 @@ +/* + * f_mass_storage.c -- Mass Storage USB Composite Function + * + * Copyright (C) 2003-2008 Alan Stern + * Copyright (C) 2009 Samsung Electronics + * Author: Michal Nazarewicz <mina86@mina86.com> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions, and the following disclaimer, + * without modification. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The names of the above-listed copyright holders may not be used + * to endorse or promote products derived from this software without + * specific prior written permission. + * + * ALTERNATIVELY, this software may be distributed under the terms of the + * GNU General Public License ("GPL") as published by the Free Software + * Foundation, either version 2 of that License or (at your option) any + * later version. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS + * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, + * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR + * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +/* + * The Mass Storage Function acts as a USB Mass Storage device, + * appearing to the host as a disk drive or as a CD-ROM drive. In + * addition to providing an example of a genuinely useful composite + * function for a USB device, it also illustrates a technique of + * double-buffering for increased throughput. + * + * For more information about MSF and in particular its module + * parameters and sysfs interface read the + * <Documentation/usb/mass-storage.txt> file. + */ + +/* + * MSF is configured by specifying a fsg_config structure. It has the + * following fields: + * + * nluns Number of LUNs function have (anywhere from 1 + * to FSG_MAX_LUNS which is 8). + * luns An array of LUN configuration values. This + * should be filled for each LUN that + * function will include (ie. for "nluns" + * LUNs). Each element of the array has + * the following fields: + * ->filename The path to the backing file for the LUN. + * Required if LUN is not marked as + * removable. + * ->ro Flag specifying access to the LUN shall be + * read-only. This is implied if CD-ROM + * emulation is enabled as well as when + * it was impossible to open "filename" + * in R/W mode. + * ->removable Flag specifying that LUN shall be indicated as + * being removable. + * ->cdrom Flag specifying that LUN shall be reported as + * being a CD-ROM. + * ->nofua Flag specifying that FUA flag in SCSI WRITE(10,12) + * commands for this LUN shall be ignored. + * + * 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. + * + * 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. As of this moment, MSF + * provides no way to deregister the gadget when thread dies -- maybe + * a callback functions is needed. + * + * To provide maximum throughput, the driver uses a circular pipeline of + * buffer heads (struct fsg_buffhd). In principle the pipeline can be + * arbitrarily long; in practice the benefits don't justify having more + * than 2 stages (i.e., double buffering). But it helps to think of the + * pipeline as being a long one. Each buffer head contains a bulk-in and + * a bulk-out request pointer (since the buffer can be used for both + * output and input -- directions always are given from the host's + * point of view) as well as a pointer to the buffer and various state + * variables. + * + * Use of the pipeline follows a simple protocol. There is a variable + * (fsg->next_buffhd_to_fill) that points to the next buffer head to use. + * At any time that buffer head may still be in use from an earlier + * request, so each buffer head has a state variable indicating whether + * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the + * buffer head to be EMPTY, filling the buffer either by file I/O or by + * USB I/O (during which the buffer head is BUSY), and marking the buffer + * head FULL when the I/O is complete. Then the buffer will be emptied + * (again possibly by USB I/O, during which it is marked BUSY) and + * finally marked EMPTY again (possibly by a completion routine). + * + * A module parameter tells the driver to avoid stalling the bulk + * endpoints wherever the transport specification allows. This is + * necessary for some UDCs like the SuperH, which cannot reliably clear a + * halt on a bulk endpoint. However, under certain circumstances the + * Bulk-only specification requires a stall. In such cases the driver + * will halt the endpoint and set a flag indicating that it should clear + * the halt in software during the next device reset. Hopefully this + * will permit everything to work correctly. Furthermore, although the + * specification allows the bulk-out endpoint to halt when the host sends + * too much data, implementing this would cause an unavoidable race. + * The driver will always use the "no-stall" approach for OUT transfers. + * + * One subtle point concerns sending status-stage responses for ep0 + * requests. Some of these requests, such as device reset, can involve + * interrupting an ongoing file I/O operation, which might take an + * arbitrarily long time. During that delay the host might give up on + * the original ep0 request and issue a new one. When that happens the + * driver should not notify the host about completion of the original + * request, as the host will no longer be waiting for it. So the driver + * assigns to each ep0 request a unique tag, and it keeps track of the + * tag value of the request associated with a long-running exception + * (device-reset, interface-change, or configuration-change). When the + * exception handler is finished, the status-stage response is submitted + * only if the current ep0 request tag is equal to the exception request + * tag. Thus only the most recently received ep0 request will get a + * status-stage response. + * + * Warning: This driver source file is too long. It ought to be split up + * into a header file plus about 3 separate .c files, to handle the details + * of the Gadget, USB Mass Storage, and SCSI protocols. + */ + + +/* #define VERBOSE_DEBUG */ +/* #define DUMP_MSGS */ + +#include <linux/blkdev.h> +#include <linux/completion.h> +#include <linux/dcache.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/fcntl.h> +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/kref.h> +#include <linux/kthread.h> +#include <linux/limits.h> +#include <linux/rwsem.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/string.h> +#include <linux/freezer.h> +#include <linux/module.h> + +#include <linux/usb/ch9.h> +#include <linux/usb/gadget.h> +#include <linux/usb/composite.h> + +#include "gadget_chips.h" +#include "configfs.h" + + +/*------------------------------------------------------------------------*/ + +#define FSG_DRIVER_DESC "Mass Storage Function" +#define FSG_DRIVER_VERSION "2009/09/11" + +static const char fsg_string_interface[] = "Mass Storage"; + +#include "storage_common.h" +#include "f_mass_storage.h" + +/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */ +static 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, +}; + +static struct usb_gadget_strings *fsg_strings_array[] = { + &fsg_stringtab, + NULL, +}; + +/*-------------------------------------------------------------------------*/ + +struct fsg_dev; +struct fsg_common; + +/* Data shared by all the FSG instances. */ +struct fsg_common { + struct usb_gadget *gadget; + struct usb_composite_dev *cdev; + struct fsg_dev *fsg, *new_fsg; + wait_queue_head_t fsg_wait; + + /* filesem protects: backing files in use */ + struct rw_semaphore filesem; + + /* lock protects: state, all the req_busy's */ + spinlock_t lock; + + struct usb_ep *ep0; /* Copy of gadget->ep0 */ + struct usb_request *ep0req; /* Copy of cdev->req */ + unsigned int ep0_req_tag; + + struct fsg_buffhd *next_buffhd_to_fill; + struct fsg_buffhd *next_buffhd_to_drain; + struct fsg_buffhd *buffhds; + unsigned int fsg_num_buffers; + + int cmnd_size; + u8 cmnd[MAX_COMMAND_SIZE]; + + unsigned int nluns; + unsigned int lun; + struct fsg_lun **luns; + struct fsg_lun *curlun; + + unsigned int bulk_out_maxpacket; + enum fsg_state state; /* For exception handling */ + unsigned int exception_req_tag; + + enum data_direction data_dir; + u32 data_size; + u32 data_size_from_cmnd; + u32 tag; + u32 residue; + u32 usb_amount_left; + + unsigned int can_stall:1; + unsigned int free_storage_on_release:1; + unsigned int phase_error:1; + unsigned int short_packet_received:1; + unsigned int bad_lun_okay:1; + unsigned int running:1; + unsigned int sysfs:1; + + int thread_wakeup_needed; + struct completion thread_notifier; + struct task_struct *thread_task; + + /* Callback functions. */ + const struct fsg_operations *ops; + /* Gadget's private data. */ + void *private_data; + + /* + * Vendor (8 chars), product (16 chars), release (4 + * hexadecimal digits) and NUL byte + */ + char inquiry_string[8 + 16 + 4 + 1]; + + struct kref ref; +}; + +struct fsg_dev { + struct usb_function function; + struct usb_gadget *gadget; /* Copy of cdev->gadget */ + struct fsg_common *common; + + u16 interface_number; + + unsigned int bulk_in_enabled:1; + unsigned int bulk_out_enabled:1; + + unsigned long atomic_bitflags; +#define IGNORE_BULK_OUT 0 + + struct usb_ep *bulk_in; + struct usb_ep *bulk_out; +}; + +static inline int __fsg_is_set(struct fsg_common *common, + const char *func, unsigned line) +{ + if (common->fsg) + return 1; + ERROR(common, "common->fsg is NULL in %s at %u\n", func, line); + WARN_ON(1); + return 0; +} + +#define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__)) + +static inline struct fsg_dev *fsg_from_func(struct usb_function *f) +{ + return container_of(f, struct fsg_dev, function); +} + +typedef void (*fsg_routine_t)(struct fsg_dev *); + +static int exception_in_progress(struct fsg_common *common) +{ + return common->state > FSG_STATE_IDLE; +} + +/* Make bulk-out requests be divisible by the maxpacket size */ +static void set_bulk_out_req_length(struct fsg_common *common, + struct fsg_buffhd *bh, unsigned int length) +{ + unsigned int rem; + + bh->bulk_out_intended_length = length; + rem = length % common->bulk_out_maxpacket; + if (rem > 0) + length += common->bulk_out_maxpacket - rem; + bh->outreq->length = length; +} + + +/*-------------------------------------------------------------------------*/ + +static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep) +{ + const char *name; + + if (ep == fsg->bulk_in) + name = "bulk-in"; + else if (ep == fsg->bulk_out) + name = "bulk-out"; + else + name = ep->name; + DBG(fsg, "%s set halt\n", name); + return usb_ep_set_halt(ep); +} + + +/*-------------------------------------------------------------------------*/ + +/* These routines may be called in process context or in_irq */ + +/* Caller must hold fsg->lock */ +static void wakeup_thread(struct fsg_common *common) +{ + smp_wmb(); /* ensure the write of bh->state is complete */ + /* Tell the main thread that something has happened */ + common->thread_wakeup_needed = 1; + if (common->thread_task) + wake_up_process(common->thread_task); +} + +static void raise_exception(struct fsg_common *common, enum fsg_state new_state) +{ + unsigned long flags; + + /* + * Do nothing if a higher-priority exception is already in progress. + * If a lower-or-equal priority exception is in progress, preempt it + * and notify the main thread by sending it a signal. + */ + spin_lock_irqsave(&common->lock, flags); + if (common->state <= new_state) { + common->exception_req_tag = common->ep0_req_tag; + common->state = new_state; + if (common->thread_task) + send_sig_info(SIGUSR1, SEND_SIG_FORCED, + common->thread_task); + } + spin_unlock_irqrestore(&common->lock, flags); +} + + +/*-------------------------------------------------------------------------*/ + +static int ep0_queue(struct fsg_common *common) +{ + int rc; + + rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC); + common->ep0->driver_data = common; + if (rc != 0 && rc != -ESHUTDOWN) { + /* We can't do much more than wait for a reset */ + WARNING(common, "error in submission: %s --> %d\n", + common->ep0->name, rc); + } + return rc; +} + + +/*-------------------------------------------------------------------------*/ + +/* Completion handlers. These always run in_irq. */ + +static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct fsg_common *common = ep->driver_data; + struct fsg_buffhd *bh = req->context; + + if (req->status || req->actual != req->length) + DBG(common, "%s --> %d, %u/%u\n", __func__, + req->status, req->actual, req->length); + if (req->status == -ECONNRESET) /* Request was cancelled */ + usb_ep_fifo_flush(ep); + + /* Hold the lock while we update the request and buffer states */ + smp_wmb(); + spin_lock(&common->lock); + bh->inreq_busy = 0; + bh->state = BUF_STATE_EMPTY; + wakeup_thread(common); + spin_unlock(&common->lock); +} + +static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct fsg_common *common = ep->driver_data; + struct fsg_buffhd *bh = req->context; + + dump_msg(common, "bulk-out", req->buf, req->actual); + if (req->status || req->actual != bh->bulk_out_intended_length) + DBG(common, "%s --> %d, %u/%u\n", __func__, + req->status, req->actual, bh->bulk_out_intended_length); + if (req->status == -ECONNRESET) /* Request was cancelled */ + usb_ep_fifo_flush(ep); + + /* Hold the lock while we update the request and buffer states */ + smp_wmb(); + spin_lock(&common->lock); + bh->outreq_busy = 0; + bh->state = BUF_STATE_FULL; + wakeup_thread(common); + spin_unlock(&common->lock); +} + +static int fsg_setup(struct usb_function *f, + const struct usb_ctrlrequest *ctrl) +{ + struct fsg_dev *fsg = fsg_from_func(f); + struct usb_request *req = fsg->common->ep0req; + u16 w_index = le16_to_cpu(ctrl->wIndex); + u16 w_value = le16_to_cpu(ctrl->wValue); + u16 w_length = le16_to_cpu(ctrl->wLength); + + if (!fsg_is_set(fsg->common)) + return -EOPNOTSUPP; + + ++fsg->common->ep0_req_tag; /* Record arrival of a new request */ + req->context = NULL; + req->length = 0; + dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl)); + + switch (ctrl->bRequest) { + + case 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 || + w_length != 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 USB_GADGET_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 || + w_length != 1) + return -EDOM; + VDBG(fsg, "get max LUN\n"); + *(u8 *)req->buf = fsg->common->nluns - 1; + + /* Respond with data/status */ + req->length = min((u16)1, w_length); + return ep0_queue(fsg->common); + } + + VDBG(fsg, + "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n", + ctrl->bRequestType, ctrl->bRequest, + le16_to_cpu(ctrl->wValue), w_index, w_length); + return -EOPNOTSUPP; +} + + +/*-------------------------------------------------------------------------*/ + +/* All the following routines run in process context */ + +/* Use this for bulk or interrupt transfers, not ep0 */ +static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep, + struct usb_request *req, int *pbusy, + enum fsg_buffer_state *state) +{ + int rc; + + if (ep == fsg->bulk_in) + dump_msg(fsg, "bulk-in", req->buf, req->length); + + spin_lock_irq(&fsg->common->lock); + *pbusy = 1; + *state = BUF_STATE_BUSY; + spin_unlock_irq(&fsg->common->lock); + rc = usb_ep_queue(ep, req, GFP_KERNEL); + if (rc != 0) { + *pbusy = 0; + *state = BUF_STATE_EMPTY; + + /* We can't do much more than wait for a reset */ + + /* + * Note: currently the net2280 driver fails zero-length + * submissions if DMA is enabled. + */ + if (rc != -ESHUTDOWN && + !(rc == -EOPNOTSUPP && req->length == 0)) + WARNING(fsg, "error in submission: %s --> %d\n", + ep->name, rc); + } +} + +static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh) +{ + if (!fsg_is_set(common)) + return false; + start_transfer(common->fsg, common->fsg->bulk_in, + bh->inreq, &bh->inreq_busy, &bh->state); + return true; +} + +static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh) +{ + if (!fsg_is_set(common)) + return false; + start_transfer(common->fsg, common->fsg->bulk_out, + bh->outreq, &bh->outreq_busy, &bh->state); + return true; +} + +static int sleep_thread(struct fsg_common *common, bool can_freeze) +{ + int rc = 0; + + /* Wait until a signal arrives or we are woken up */ + for (;;) { + if (can_freeze) + try_to_freeze(); + set_current_state(TASK_INTERRUPTIBLE); + if (signal_pending(current)) { + rc = -EINTR; + break; + } + if (common->thread_wakeup_needed) + break; + schedule(); + } + __set_current_state(TASK_RUNNING); + common->thread_wakeup_needed = 0; + smp_rmb(); /* ensure the latest bh->state is visible */ + return rc; +} + + +/*-------------------------------------------------------------------------*/ + +static int do_read(struct fsg_common *common) +{ + struct fsg_lun *curlun = common->curlun; + u32 lba; + struct fsg_buffhd *bh; + int rc; + u32 amount_left; + loff_t file_offset, file_offset_tmp; + unsigned int amount; + ssize_t nread; + + /* + * Get the starting Logical Block Address and check that it's + * not too big. + */ + if (common->cmnd[0] == READ_6) + lba = get_unaligned_be24(&common->cmnd[1]); + else { + lba = get_unaligned_be32(&common->cmnd[2]); + + /* + * We allow DPO (Disable Page Out = don't save data in the + * cache) and FUA (Force Unit Access = don't read from the + * cache), but we don't implement them. + */ + if ((common->cmnd[1] & ~0x18) != 0) { + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + } + if (lba >= curlun->num_sectors) { + curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; + return -EINVAL; + } + file_offset = ((loff_t) lba) << curlun->blkbits; + + /* Carry out the file reads */ + amount_left = common->data_size_from_cmnd; + if (unlikely(amount_left == 0)) + return -EIO; /* No default reply */ + + for (;;) { + /* + * Figure out how much we need to read: + * Try to read the remaining amount. + * But don't read more than the buffer size. + * And don't try to read past the end of the file. + */ + amount = min(amount_left, FSG_BUFLEN); + amount = min((loff_t)amount, + curlun->file_length - file_offset); + + /* Wait for the next buffer to become available */ + bh = common->next_buffhd_to_fill; + while (bh->state != BUF_STATE_EMPTY) { + rc = sleep_thread(common, false); + 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; + common->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; + if (!start_in_transfer(common, bh)) + /* Don't know what to do if common->fsg is NULL */ + return -EIO; + common->next_buffhd_to_fill = bh->next; + } + + return -EIO; /* No default reply */ +} + + +/*-------------------------------------------------------------------------*/ + +static int do_write(struct fsg_common *common) +{ + struct fsg_lun *curlun = common->curlun; + u32 lba; + struct fsg_buffhd *bh; + int get_some_more; + u32 amount_left_to_req, amount_left_to_write; + loff_t usb_offset, file_offset, file_offset_tmp; + unsigned int amount; + ssize_t nwritten; + int rc; + + if (curlun->ro) { + curlun->sense_data = SS_WRITE_PROTECTED; + return -EINVAL; + } + spin_lock(&curlun->filp->f_lock); + curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */ + spin_unlock(&curlun->filp->f_lock); + + /* + * Get the starting Logical Block Address and check that it's + * not too big + */ + if (common->cmnd[0] == WRITE_6) + lba = get_unaligned_be24(&common->cmnd[1]); + else { + lba = get_unaligned_be32(&common->cmnd[2]); + + /* + * We allow DPO (Disable Page Out = don't save data in the + * cache) and FUA (Force Unit Access = write directly to the + * medium). We don't implement DPO; we implement FUA by + * performing synchronous output. + */ + if (common->cmnd[1] & ~0x18) { + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */ + spin_lock(&curlun->filp->f_lock); + curlun->filp->f_flags |= O_SYNC; + spin_unlock(&curlun->filp->f_lock); + } + } + if (lba >= curlun->num_sectors) { + curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; + return -EINVAL; + } + + /* Carry out the file writes */ + get_some_more = 1; + file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits; + 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 not more than the buffer size. + */ + amount = min(amount_left_to_req, FSG_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; + common->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(common, bh, amount); + if (!start_out_transfer(common, bh)) + /* Dunno what to do if common->fsg is NULL */ + return -EIO; + common->next_buffhd_to_fill = bh->next; + continue; + } + + /* Write the received data to the backing file */ + bh = common->next_buffhd_to_drain; + if (bh->state == BUF_STATE_EMPTY && !get_some_more) + break; /* We stopped early */ + if (bh->state == BUF_STATE_FULL) { + smp_rmb(); + common->next_buffhd_to_drain = bh->next; + bh->state = BUF_STATE_EMPTY; + + /* Did something go wrong with the transfer? */ + if (bh->outreq->status != 0) { + curlun->sense_data = SS_COMMUNICATION_FAILURE; + curlun->sense_data_info = + file_offset >> 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; + common->residue -= nwritten; + + /* If an error occurred, report it and its position */ + if (nwritten < amount) { + curlun->sense_data = SS_WRITE_ERROR; + curlun->sense_data_info = + file_offset >> 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) { + common->short_packet_received = 1; + break; + } + continue; + } + + /* Wait for something to happen */ + rc = sleep_thread(common, false); + if (rc) + return rc; + } + + return -EIO; /* No default reply */ +} + + +/*-------------------------------------------------------------------------*/ + +static int do_synchronize_cache(struct fsg_common *common) +{ + struct fsg_lun *curlun = common->curlun; + int rc; + + /* We ignore the requested LBA and write out all file's + * dirty data buffers. */ + rc = fsg_lun_fsync_sub(curlun); + if (rc) + curlun->sense_data = SS_WRITE_ERROR; + return 0; +} + + +/*-------------------------------------------------------------------------*/ + +static void invalidate_sub(struct fsg_lun *curlun) +{ + struct file *filp = curlun->filp; + struct inode *inode = file_inode(filp); + unsigned long rc; + + rc = invalidate_mapping_pages(inode->i_mapping, 0, -1); + VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc); +} + +static int do_verify(struct fsg_common *common) +{ + struct fsg_lun *curlun = common->curlun; + u32 lba; + u32 verification_length; + struct fsg_buffhd *bh = common->next_buffhd_to_fill; + loff_t file_offset, file_offset_tmp; + u32 amount_left; + unsigned int amount; + ssize_t nread; + + /* + * Get the starting Logical Block Address and check that it's + * not too big. + */ + lba = get_unaligned_be32(&common->cmnd[2]); + if (lba >= curlun->num_sectors) { + curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; + return -EINVAL; + } + + /* + * We allow DPO (Disable Page Out = don't save data in the + * cache) but we don't implement it. + */ + if (common->cmnd[1] & ~0x10) { + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + + verification_length = get_unaligned_be16(&common->cmnd[7]); + if (unlikely(verification_length == 0)) + return -EIO; /* No default reply */ + + /* Prepare to carry out the file verify */ + amount_left = verification_length << 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(amount_left, FSG_BUFLEN); + amount = min((loff_t)amount, + curlun->file_length - file_offset); + if (amount == 0) { + curlun->sense_data = + SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; + curlun->sense_data_info = + file_offset >> 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_common *common, struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = common->curlun; + u8 *buf = (u8 *) bh->buf; + + if (!curlun) { /* Unsupported LUNs are okay */ + common->bad_lun_okay = 1; + memset(buf, 0, 36); + buf[0] = 0x7f; /* Unsupported, no device-type */ + buf[4] = 31; /* Additional length */ + return 36; + } + + buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK; + buf[1] = curlun->removable ? 0x80 : 0; + buf[2] = 2; /* ANSI SCSI level 2 */ + buf[3] = 2; /* SCSI-2 INQUIRY data format */ + buf[4] = 31; /* Additional length */ + buf[5] = 0; /* No special options */ + buf[6] = 0; + buf[7] = 0; + memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string); + return 36; +} + +static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = common->curlun; + u8 *buf = (u8 *) bh->buf; + u32 sd, sdinfo; + int valid; + + /* + * From the SCSI-2 spec., section 7.9 (Unit attention condition): + * + * If a REQUEST SENSE command is received from an initiator + * with a pending unit attention condition (before the target + * generates the contingent allegiance condition), then the + * target shall either: + * a) report any pending sense data and preserve the unit + * attention condition on the logical unit, or, + * b) report the unit attention condition, may discard any + * pending sense data, and clear the unit attention + * condition on the logical unit for that initiator. + * + * FSG normally uses option a); enable this code to use option b). + */ +#if 0 + if (curlun && curlun->unit_attention_data != SS_NO_SENSE) { + curlun->sense_data = curlun->unit_attention_data; + curlun->unit_attention_data = SS_NO_SENSE; + } +#endif + + if (!curlun) { /* Unsupported LUNs are okay */ + common->bad_lun_okay = 1; + sd = SS_LOGICAL_UNIT_NOT_SUPPORTED; + sdinfo = 0; + valid = 0; + } else { + sd = curlun->sense_data; + sdinfo = curlun->sense_data_info; + valid = curlun->info_valid << 7; + curlun->sense_data = SS_NO_SENSE; + curlun->sense_data_info = 0; + curlun->info_valid = 0; + } + + memset(buf, 0, 18); + buf[0] = valid | 0x70; /* Valid, current error */ + buf[2] = SK(sd); + put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */ + buf[7] = 18 - 8; /* Additional sense length */ + buf[12] = ASC(sd); + buf[13] = ASCQ(sd); + return 18; +} + +static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = common->curlun; + u32 lba = get_unaligned_be32(&common->cmnd[2]); + int pmi = common->cmnd[8]; + u8 *buf = (u8 *)bh->buf; + + /* Check the PMI and LBA fields */ + if (pmi > 1 || (pmi == 0 && lba != 0)) { + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + + put_unaligned_be32(curlun->num_sectors - 1, &buf[0]); + /* Max logical block */ + put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */ + return 8; +} + +static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = common->curlun; + int msf = common->cmnd[1] & 0x02; + u32 lba = get_unaligned_be32(&common->cmnd[2]); + u8 *buf = (u8 *)bh->buf; + + if (common->cmnd[1] & ~0x02) { /* Mask away MSF */ + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + if (lba >= curlun->num_sectors) { + curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; + return -EINVAL; + } + + memset(buf, 0, 8); + buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */ + store_cdrom_address(&buf[4], msf, lba); + return 8; +} + +static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = common->curlun; + int msf = common->cmnd[1] & 0x02; + int start_track = common->cmnd[6]; + u8 *buf = (u8 *)bh->buf; + + if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */ + start_track > 1) { + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + + memset(buf, 0, 20); + buf[1] = (20-2); /* TOC data length */ + buf[2] = 1; /* First track number */ + buf[3] = 1; /* Last track number */ + buf[5] = 0x16; /* Data track, copying allowed */ + buf[6] = 0x01; /* Only track is number 1 */ + store_cdrom_address(&buf[8], msf, 0); + + buf[13] = 0x16; /* Lead-out track is data */ + buf[14] = 0xAA; /* Lead-out track number */ + store_cdrom_address(&buf[16], msf, curlun->num_sectors); + return 20; +} + +static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = common->curlun; + int mscmnd = common->cmnd[0]; + u8 *buf = (u8 *) bh->buf; + u8 *buf0 = buf; + int pc, page_code; + int changeable_values, all_pages; + int valid_page = 0; + int len, limit; + + if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */ + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + pc = common->cmnd[2] >> 6; + page_code = common->cmnd[2] & 0x3f; + if (pc == 3) { + curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED; + return -EINVAL; + } + changeable_values = (pc == 1); + all_pages = (page_code == 0x3f); + + /* + * Write the mode parameter header. Fixed values are: default + * medium type, no cache control (DPOFUA), and no block descriptors. + * The only variable value is the WriteProtect bit. We will fill in + * the mode data length later. + */ + memset(buf, 0, 8); + if (mscmnd == MODE_SENSE) { + buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */ + buf += 4; + limit = 255; + } else { /* MODE_SENSE_10 */ + buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */ + buf += 8; + limit = 65535; /* Should really be FSG_BUFLEN */ + } + + /* No block descriptors */ + + /* + * The mode pages, in numerical order. The only page we support + * is the Caching page. + */ + if (page_code == 0x08 || all_pages) { + valid_page = 1; + buf[0] = 0x08; /* Page code */ + buf[1] = 10; /* Page length */ + memset(buf+2, 0, 10); /* None of the fields are changeable */ + + if (!changeable_values) { + buf[2] = 0x04; /* Write cache enable, */ + /* Read cache not disabled */ + /* No cache retention priorities */ + put_unaligned_be16(0xffff, &buf[4]); + /* Don't disable prefetch */ + /* Minimum prefetch = 0 */ + put_unaligned_be16(0xffff, &buf[8]); + /* Maximum prefetch */ + put_unaligned_be16(0xffff, &buf[10]); + /* Maximum prefetch ceiling */ + } + buf += 12; + } + + /* + * Check that a valid page was requested and the mode data length + * isn't too long. + */ + len = buf - buf0; + if (!valid_page || len > limit) { + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + + /* Store the mode data length */ + if (mscmnd == MODE_SENSE) + buf0[0] = len - 1; + else + put_unaligned_be16(len - 2, buf0); + return len; +} + +static int do_start_stop(struct fsg_common *common) +{ + struct fsg_lun *curlun = common->curlun; + int loej, start; + + if (!curlun) { + return -EINVAL; + } else if (!curlun->removable) { + curlun->sense_data = SS_INVALID_COMMAND; + return -EINVAL; + } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */ + (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */ + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + + loej = common->cmnd[4] & 0x02; + start = common->cmnd[4] & 0x01; + + /* + * Our emulation doesn't support mounting; the medium is + * available for use as soon as it is loaded. + */ + if (start) { + if (!fsg_lun_is_open(curlun)) { + curlun->sense_data = SS_MEDIUM_NOT_PRESENT; + return -EINVAL; + } + return 0; + } + + /* Are we allowed to unload the media? */ + if (curlun->prevent_medium_removal) { + LDBG(curlun, "unload attempt prevented\n"); + curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED; + return -EINVAL; + } + + if (!loej) + return 0; + + up_read(&common->filesem); + down_write(&common->filesem); + fsg_lun_close(curlun); + up_write(&common->filesem); + down_read(&common->filesem); + + return 0; +} + +static int do_prevent_allow(struct fsg_common *common) +{ + struct fsg_lun *curlun = common->curlun; + int prevent; + + if (!common->curlun) { + return -EINVAL; + } else if (!common->curlun->removable) { + common->curlun->sense_data = SS_INVALID_COMMAND; + return -EINVAL; + } + + prevent = common->cmnd[4] & 0x01; + if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */ + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + + if (curlun->prevent_medium_removal && !prevent) + fsg_lun_fsync_sub(curlun); + curlun->prevent_medium_removal = prevent; + return 0; +} + +static int do_read_format_capacities(struct fsg_common *common, + struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = common->curlun; + u8 *buf = (u8 *) bh->buf; + + buf[0] = buf[1] = buf[2] = 0; + buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */ + buf += 4; + + put_unaligned_be32(curlun->num_sectors, &buf[0]); + /* Number of blocks */ + put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */ + buf[4] = 0x02; /* Current capacity */ + return 12; +} + +static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = common->curlun; + + /* We don't support MODE SELECT */ + if (curlun) + curlun->sense_data = SS_INVALID_COMMAND; + return -EINVAL; +} + + +/*-------------------------------------------------------------------------*/ + +static int halt_bulk_in_endpoint(struct fsg_dev *fsg) +{ + int rc; + + rc = fsg_set_halt(fsg, fsg->bulk_in); + if (rc == -EAGAIN) + VDBG(fsg, "delayed bulk-in endpoint halt\n"); + while (rc != 0) { + if (rc != -EAGAIN) { + WARNING(fsg, "usb_ep_set_halt -> %d\n", rc); + rc = 0; + break; + } + + /* Wait for a short time and then try again */ + if (msleep_interruptible(100) != 0) + return -EINTR; + rc = usb_ep_set_halt(fsg->bulk_in); + } + return rc; +} + +static int wedge_bulk_in_endpoint(struct fsg_dev *fsg) +{ + int rc; + + DBG(fsg, "bulk-in set wedge\n"); + rc = usb_ep_set_wedge(fsg->bulk_in); + if (rc == -EAGAIN) + VDBG(fsg, "delayed bulk-in endpoint wedge\n"); + while (rc != 0) { + if (rc != -EAGAIN) { + WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc); + rc = 0; + break; + } + + /* Wait for a short time and then try again */ + if (msleep_interruptible(100) != 0) + return -EINTR; + rc = usb_ep_set_wedge(fsg->bulk_in); + } + return rc; +} + +static int throw_away_data(struct fsg_common *common) +{ + struct fsg_buffhd *bh; + u32 amount; + int rc; + + for (bh = common->next_buffhd_to_drain; + bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0; + bh = common->next_buffhd_to_drain) { + + /* Throw away the data in a filled buffer */ + if (bh->state == BUF_STATE_FULL) { + smp_rmb(); + bh->state = BUF_STATE_EMPTY; + common->next_buffhd_to_drain = bh->next; + + /* A short packet or an error ends everything */ + if (bh->outreq->actual < bh->bulk_out_intended_length || + bh->outreq->status != 0) { + raise_exception(common, + FSG_STATE_ABORT_BULK_OUT); + return -EINTR; + } + continue; + } + + /* Try to submit another request if we need one */ + bh = common->next_buffhd_to_fill; + if (bh->state == BUF_STATE_EMPTY + && common->usb_amount_left > 0) { + amount = min(common->usb_amount_left, FSG_BUFLEN); + + /* + * 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(common, bh, amount); + if (!start_out_transfer(common, bh)) + /* Dunno what to do if common->fsg is NULL */ + return -EIO; + common->next_buffhd_to_fill = bh->next; + common->usb_amount_left -= amount; + continue; + } + + /* Otherwise wait for something to happen */ + rc = sleep_thread(common, true); + 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 */ + + /* Don't know what to do if common->fsg is NULL */ + } else if (!fsg_is_set(common)) { + rc = -EIO; + + /* If there's no residue, simply send the last buffer */ + } else if (common->residue == 0) { + bh->inreq->zero = 0; + if (!start_in_transfer(common, bh)) + return -EIO; + common->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; + if (!start_in_transfer(common, bh)) + rc = -EIO; + common->next_buffhd_to_fill = bh->next; + if (common->can_stall) + rc = halt_bulk_in_endpoint(common->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 (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 = -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 (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 = -EINTR; +#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->curlun; + 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, true); + if (rc) + return rc; + } + + if (curlun) { + sd = curlun->sense_data; + sdinfo = curlun->sense_data_info; + } 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; + if (!start_in_transfer(common, bh)) + /* Don't know what to do if common->fsg is NULL */ + return -EIO; + + common->next_buffhd_to_fill = bh->next; + return 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; + unsigned 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 %u from CBW, not LUN %u from CDB\n", + common->lun, lun); + + /* Check the LUN */ + curlun = common->curlun; + if (curlun) { + if (common->cmnd[0] != REQUEST_SENSE) { + curlun->sense_data = SS_NO_SENSE; + curlun->sense_data_info = 0; + curlun->info_valid = 0; + } + } else { + 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] != INQUIRY && + common->cmnd[0] != REQUEST_SENSE) { + DBG(common, "unsupported LUN %u\n", common->lun); + return -EINVAL; + } + } + + /* + * If a unit attention condition exists, only INQUIRY and + * REQUEST SENSE commands are allowed; anything else must fail. + */ + if (curlun && curlun->unit_attention_data != SS_NO_SENSE && + common->cmnd[0] != INQUIRY && + common->cmnd[0] != REQUEST_SENSE) { + curlun->sense_data = curlun->unit_attention_data; + curlun->unit_attention_data = SS_NO_SENSE; + return -EINVAL; + } + + /* Check that only command bytes listed in the mask are non-zero */ + 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; + } + } + + /* If the medium isn't mounted and the command needs to access + * it, return an error. */ + if (curlun && !fsg_lun_is_open(curlun) && needs_medium) { + curlun->sense_data = SS_MEDIUM_NOT_PRESENT; + return -EINVAL; + } + + return 0; +} + +/* wrapper of check_command for data size in blocks handling */ +static int check_command_size_in_blocks(struct fsg_common *common, + int cmnd_size, enum data_direction data_dir, + unsigned int mask, int needs_medium, const char *name) +{ + if (common->curlun) + common->data_size_from_cmnd <<= common->curlun->blkbits; + return check_command(common, cmnd_size, data_dir, + mask, needs_medium, name); +} + +static int do_scsi_command(struct fsg_common *common) +{ + struct fsg_buffhd *bh; + int rc; + int reply = -EINVAL; + int i; + static char unknown[16]; + + 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, true); + 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 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 MODE_SELECT: + 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 MODE_SELECT_10: + 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 MODE_SENSE: + 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 MODE_SENSE_10: + 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 ALLOW_MEDIUM_REMOVAL: + 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 READ_6: + i = common->cmnd[4]; + common->data_size_from_cmnd = (i == 0) ? 256 : i; + reply = check_command_size_in_blocks(common, 6, + DATA_DIR_TO_HOST, + (7<<1) | (1<<4), 1, + "READ(6)"); + if (reply == 0) + reply = do_read(common); + break; + + case READ_10: + common->data_size_from_cmnd = + get_unaligned_be16(&common->cmnd[7]); + reply = check_command_size_in_blocks(common, 10, + DATA_DIR_TO_HOST, + (1<<1) | (0xf<<2) | (3<<7), 1, + "READ(10)"); + if (reply == 0) + reply = do_read(common); + break; + + case READ_12: + common->data_size_from_cmnd = + get_unaligned_be32(&common->cmnd[6]); + reply = check_command_size_in_blocks(common, 12, + DATA_DIR_TO_HOST, + (1<<1) | (0xf<<2) | (0xf<<6), 1, + "READ(12)"); + if (reply == 0) + reply = do_read(common); + break; + + case READ_CAPACITY: + 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 READ_HEADER: + if (!common->curlun || !common->curlun->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 READ_TOC: + if (!common->curlun || !common->curlun->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 READ_FORMAT_CAPACITIES: + 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 REQUEST_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 START_STOP: + 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 SYNCHRONIZE_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 TEST_UNIT_READY: + 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 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 WRITE_6: + i = common->cmnd[4]; + common->data_size_from_cmnd = (i == 0) ? 256 : i; + reply = check_command_size_in_blocks(common, 6, + DATA_DIR_FROM_HOST, + (7<<1) | (1<<4), 1, + "WRITE(6)"); + if (reply == 0) + reply = do_write(common); + break; + + case WRITE_10: + common->data_size_from_cmnd = + get_unaligned_be16(&common->cmnd[7]); + reply = check_command_size_in_blocks(common, 10, + DATA_DIR_FROM_HOST, + (1<<1) | (0xf<<2) | (3<<7), 1, + "WRITE(10)"); + if (reply == 0) + reply = do_write(common); + break; + + case WRITE_12: + common->data_size_from_cmnd = + get_unaligned_be32(&common->cmnd[6]); + reply = check_command_size_in_blocks(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 FORMAT_UNIT: + case RELEASE: + case RESERVE: + case SEND_DIAGNOSTIC: + /* 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, ~0, 0, unknown); + if (reply == 0) { + common->curlun->sense_data = SS_INVALID_COMMAND; + reply = -EINVAL; + } + break; + } + up_read(&common->filesem); + + if (reply == -EINTR || signal_pending(current)) + return -EINTR; + + /* Set up the single reply buffer for finish_reply() */ + if (reply == -EINVAL) + reply = 0; /* Error reply length */ + if (reply >= 0 && 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; + if (common->lun < common->nluns) + common->curlun = common->luns[common->lun]; + else + common->curlun = NULL; + 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, true); + 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); + if (!start_out_transfer(common, bh)) + /* 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, true); + if (rc) + return rc; + } + smp_rmb(); + rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO; + bh->state = BUF_STATE_EMPTY; + + return rc; +} + + +/*-------------------------------------------------------------------------*/ + +static int alloc_request(struct fsg_common *common, struct usb_ep *ep, + struct usb_request **preq) +{ + *preq = usb_ep_alloc_request(ep, GFP_ATOMIC); + 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 < common->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->driver_data = NULL; + fsg->bulk_in_enabled = 0; + } + if (fsg->bulk_out_enabled) { + usb_ep_disable(fsg->bulk_out); + fsg->bulk_out->driver_data = NULL; + 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 */ + rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in); + if (rc) + goto reset; + rc = usb_ep_enable(fsg->bulk_in); + if (rc) + goto reset; + fsg->bulk_in->driver_data = common; + fsg->bulk_in_enabled = 1; + + rc = config_ep_by_speed(common->gadget, &(fsg->function), + fsg->bulk_out); + if (rc) + goto reset; + rc = usb_ep_enable(fsg->bulk_out); + if (rc) + goto reset; + fsg->bulk_out->driver_data = common; + fsg->bulk_out_enabled = 1; + common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc); + clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags); + + /* Allocate the requests */ + for (i = 0; i < common->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; + for (i = 0; i < common->nluns; ++i) + if (common->luns[i]) + common->luns[i]->unit_attention_data = + SS_RESET_OCCURRED; + 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 USB_GADGET_DELAYED_STATUS; +} + +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) +{ + siginfo_t info; + int i; + struct fsg_buffhd *bh; + enum fsg_state old_state; + struct fsg_lun *curlun; + unsigned int exception_req_tag; + + /* + * Clear the existing signals. Anything but SIGUSR1 is converted + * into a high-priority EXIT exception. + */ + for (;;) { + int sig = + dequeue_signal_lock(current, ¤t->blocked, &info); + if (!sig) + break; + if (sig != SIGUSR1) { + if (common->state < FSG_STATE_EXIT) + DBG(common, "Main thread exiting on signal\n"); + raise_exception(common, FSG_STATE_EXIT); + } + } + + /* Cancel all the pending transfers */ + if (likely(common->fsg)) { + for (i = 0; i < common->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 < common->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, true)) + 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. + */ + spin_lock_irq(&common->lock); + + for (i = 0; i < common->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; + + 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]; + if (!curlun) + continue; + curlun->prevent_medium_removal = 0; + curlun->sense_data = SS_NO_SENSE; + curlun->unit_attention_data = SS_NO_SENSE; + curlun->sense_data_info = 0; + curlun->info_valid = 0; + } + common->state = FSG_STATE_IDLE; + } + spin_unlock_irq(&common->lock); + + /* Carry out any extra actions required for the exception */ + switch (old_state) { + case FSG_STATE_ABORT_BULK_OUT: + send_status(common); + spin_lock_irq(&common->lock); + if (common->state == FSG_STATE_STATUS_PHASE) + common->state = FSG_STATE_IDLE; + spin_unlock_irq(&common->lock); + break; + + case FSG_STATE_RESET: + /* + * In case we were forced against our will to halt a + * bulk endpoint, clear the halt now. (The SuperH UDC + * requires this.) + */ + if (!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 */ + + /* + * Technically this should go here, but it would only be + * a waste of time. Ditto for the INTERFACE_CHANGE and + * CONFIG_CHANGE cases. + */ + /* for (i = 0; i < common->nluns; ++i) */ + /* if (common->luns[i]) */ + /* common->luns[i]->unit_attention_data = */ + /* SS_RESET_OCCURRED; */ + break; + + case FSG_STATE_CONFIG_CHANGE: + do_set_interface(common, common->new_fsg); + if (common->new_fsg) + usb_composite_setup_continue(common->cdev); + break; + + case FSG_STATE_EXIT: + case FSG_STATE_TERMINATED: + do_set_interface(common, NULL); /* Free resources */ + spin_lock_irq(&common->lock); + common->state = FSG_STATE_TERMINATED; /* Stop the thread */ + spin_unlock_irq(&common->lock); + 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_; + + /* + * Allow the thread to be killed by a signal, but set the signal mask + * to block everything but INT, TERM, KILL, and USR1. + */ + allow_signal(SIGINT); + allow_signal(SIGTERM); + allow_signal(SIGKILL); + allow_signal(SIGUSR1); + + /* Allow the thread to be frozen */ + set_freezable(); + + /* + * Arrange for userspace references to be interpreted as kernel + * pointers. That way we can pass a kernel pointer to a routine + * that expects a __user pointer and it will work okay. + */ + set_fs(get_ds()); + + /* The main loop */ + while (common->state != FSG_STATE_TERMINATED) { + if (exception_in_progress(common) || signal_pending(current)) { + handle_exception(common); + continue; + } + + if (!common->running) { + sleep_thread(common, true); + continue; + } + + if (get_next_command(common)) + continue; + + spin_lock_irq(&common->lock); + if (!exception_in_progress(common)) + common->state = FSG_STATE_DATA_PHASE; + spin_unlock_irq(&common->lock); + + if (do_scsi_command(common) || finish_reply(common)) + continue; + + spin_lock_irq(&common->lock); + if (!exception_in_progress(common)) + common->state = FSG_STATE_STATUS_PHASE; + spin_unlock_irq(&common->lock); + + if (send_status(common)) + continue; + + spin_lock_irq(&common->lock); + if (!exception_in_progress(common)) + common->state = FSG_STATE_IDLE; + spin_unlock_irq(&common->lock); + } + + spin_lock_irq(&common->lock); + common->thread_task = NULL; + spin_unlock_irq(&common->lock); + + if (!common->ops || !common->ops->thread_exits + || common->ops->thread_exits(common) < 0) { + struct fsg_lun **curlun_it = common->luns; + unsigned i = common->nluns; + + down_write(&common->filesem); + for (; i--; ++curlun_it) { + struct fsg_lun *curlun = *curlun_it; + if (!curlun || !fsg_lun_is_open(curlun)) + continue; + + fsg_lun_close(curlun); + curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT; + } + up_write(&common->filesem); + } + + /* Let fsg_unbind() know the thread has exited */ + complete_and_exit(&common->thread_notifier, 0); +} + + +/*************************** DEVICE ATTRIBUTES ***************************/ + +static ssize_t ro_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct fsg_lun *curlun = fsg_lun_from_dev(dev); + + return fsg_show_ro(curlun, buf); +} + +static ssize_t nofua_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct fsg_lun *curlun = fsg_lun_from_dev(dev); + + return fsg_show_nofua(curlun, buf); +} + +static ssize_t file_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct fsg_lun *curlun = fsg_lun_from_dev(dev); + struct rw_semaphore *filesem = dev_get_drvdata(dev); + + return fsg_show_file(curlun, filesem, buf); +} + +static ssize_t ro_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct fsg_lun *curlun = fsg_lun_from_dev(dev); + struct rw_semaphore *filesem = dev_get_drvdata(dev); + + return fsg_store_ro(curlun, filesem, buf, count); +} + +static ssize_t nofua_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct fsg_lun *curlun = fsg_lun_from_dev(dev); + + return fsg_store_nofua(curlun, buf, count); +} + +static ssize_t file_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct fsg_lun *curlun = fsg_lun_from_dev(dev); + struct rw_semaphore *filesem = dev_get_drvdata(dev); + + return fsg_store_file(curlun, filesem, buf, count); +} + +static DEVICE_ATTR_RW(ro); +static DEVICE_ATTR_RW(nofua); +static DEVICE_ATTR_RW(file); + +static struct device_attribute dev_attr_ro_cdrom = __ATTR_RO(ro); +static struct device_attribute dev_attr_file_nonremovable = __ATTR_RO(file); + + +/****************************** FSG COMMON ******************************/ + +static void fsg_common_release(struct kref *ref); + +static void fsg_lun_release(struct device *dev) +{ + /* Nothing needs to be done */ +} + +void fsg_common_get(struct fsg_common *common) +{ + kref_get(&common->ref); +} +EXPORT_SYMBOL_GPL(fsg_common_get); + +void fsg_common_put(struct fsg_common *common) +{ + kref_put(&common->ref, fsg_common_release); +} +EXPORT_SYMBOL_GPL(fsg_common_put); + +/* check if fsg_num_buffers is within a valid range */ +static inline int fsg_num_buffers_validate(unsigned int fsg_num_buffers) +{ + if (fsg_num_buffers >= 2 && fsg_num_buffers <= 4) + return 0; + pr_err("fsg_num_buffers %u is out of range (%d to %d)\n", + fsg_num_buffers, 2, 4); + return -EINVAL; +} + +static struct fsg_common *fsg_common_setup(struct fsg_common *common) +{ + if (!common) { + common = kzalloc(sizeof(*common), GFP_KERNEL); + if (!common) + return ERR_PTR(-ENOMEM); + common->free_storage_on_release = 1; + } else { + common->free_storage_on_release = 0; + } + init_rwsem(&common->filesem); + spin_lock_init(&common->lock); + kref_init(&common->ref); + init_completion(&common->thread_notifier); + init_waitqueue_head(&common->fsg_wait); + common->state = FSG_STATE_TERMINATED; + + return common; +} + +void fsg_common_set_sysfs(struct fsg_common *common, bool sysfs) +{ + common->sysfs = sysfs; +} +EXPORT_SYMBOL_GPL(fsg_common_set_sysfs); + +static void _fsg_common_free_buffers(struct fsg_buffhd *buffhds, unsigned n) +{ + if (buffhds) { + struct fsg_buffhd *bh = buffhds; + while (n--) { + kfree(bh->buf); + ++bh; + } + kfree(buffhds); + } +} + +int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n) +{ + struct fsg_buffhd *bh, *buffhds; + int i, rc; + + rc = fsg_num_buffers_validate(n); + if (rc != 0) + return rc; + + buffhds = kcalloc(n, sizeof(*buffhds), GFP_KERNEL); + if (!buffhds) + return -ENOMEM; + + /* Data buffers cyclic list */ + bh = buffhds; + i = n; + goto buffhds_first_it; + do { + bh->next = bh + 1; + ++bh; +buffhds_first_it: + bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL); + if (unlikely(!bh->buf)) + goto error_release; + } while (--i); + bh->next = buffhds; + + _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers); + common->fsg_num_buffers = n; + common->buffhds = buffhds; + + return 0; + +error_release: + /* + * "buf"s pointed to by heads after n - i are NULL + * so releasing them won't hurt + */ + _fsg_common_free_buffers(buffhds, n); + + return -ENOMEM; +} +EXPORT_SYMBOL_GPL(fsg_common_set_num_buffers); + +static inline void fsg_common_remove_sysfs(struct fsg_lun *lun) +{ + device_remove_file(&lun->dev, &dev_attr_nofua); + /* + * device_remove_file() => + * + * here the attr (e.g. dev_attr_ro) is only used to be passed to: + * + * sysfs_remove_file() => + * + * here e.g. both dev_attr_ro_cdrom and dev_attr_ro are in + * the same namespace and + * from here only attr->name is passed to: + * + * sysfs_hash_and_remove() + * + * attr->name is the same for dev_attr_ro_cdrom and + * dev_attr_ro + * attr->name is the same for dev_attr_file and + * dev_attr_file_nonremovable + * + * so we don't differentiate between removing e.g. dev_attr_ro_cdrom + * and dev_attr_ro + */ + device_remove_file(&lun->dev, &dev_attr_ro); + device_remove_file(&lun->dev, &dev_attr_file); +} + +void fsg_common_remove_lun(struct fsg_lun *lun, bool sysfs) +{ + if (sysfs) { + fsg_common_remove_sysfs(lun); + device_unregister(&lun->dev); + } + fsg_lun_close(lun); + kfree(lun); +} +EXPORT_SYMBOL_GPL(fsg_common_remove_lun); + +static void _fsg_common_remove_luns(struct fsg_common *common, int n) +{ + int i; + + for (i = 0; i < n; ++i) + if (common->luns[i]) { + fsg_common_remove_lun(common->luns[i], common->sysfs); + common->luns[i] = NULL; + } +} +EXPORT_SYMBOL_GPL(fsg_common_remove_luns); + +void fsg_common_remove_luns(struct fsg_common *common) +{ + _fsg_common_remove_luns(common, common->nluns); +} + +void fsg_common_free_luns(struct fsg_common *common) +{ + fsg_common_remove_luns(common); + kfree(common->luns); + common->luns = NULL; +} +EXPORT_SYMBOL_GPL(fsg_common_free_luns); + +int fsg_common_set_nluns(struct fsg_common *common, int nluns) +{ + struct fsg_lun **curlun; + + /* Find out how many LUNs there should be */ + if (nluns < 1 || nluns > FSG_MAX_LUNS) { + pr_err("invalid number of LUNs: %u\n", nluns); + return -EINVAL; + } + + curlun = kcalloc(nluns, sizeof(*curlun), GFP_KERNEL); + if (unlikely(!curlun)) + return -ENOMEM; + + if (common->luns) + fsg_common_free_luns(common); + + common->luns = curlun; + common->nluns = nluns; + + pr_info("Number of LUNs=%d\n", common->nluns); + + return 0; +} +EXPORT_SYMBOL_GPL(fsg_common_set_nluns); + +void fsg_common_set_ops(struct fsg_common *common, + const struct fsg_operations *ops) +{ + common->ops = ops; +} +EXPORT_SYMBOL_GPL(fsg_common_set_ops); + +void fsg_common_free_buffers(struct fsg_common *common) +{ + _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers); + common->buffhds = NULL; +} +EXPORT_SYMBOL_GPL(fsg_common_free_buffers); + +int fsg_common_set_cdev(struct fsg_common *common, + struct usb_composite_dev *cdev, bool can_stall) +{ + struct usb_string *us; + + common->gadget = cdev->gadget; + common->ep0 = cdev->gadget->ep0; + common->ep0req = cdev->req; + common->cdev = cdev; + + us = usb_gstrings_attach(cdev, fsg_strings_array, + ARRAY_SIZE(fsg_strings)); + if (IS_ERR(us)) + return PTR_ERR(us); + + fsg_intf_desc.iInterface = us[FSG_STRING_INTERFACE].id; + + /* + * Some peripheral controllers are known not to be able to + * halt bulk endpoints correctly. If one of them is present, + * disable stalls. + */ + common->can_stall = can_stall && !(gadget_is_at91(common->gadget)); + + return 0; +} +EXPORT_SYMBOL_GPL(fsg_common_set_cdev); + +static inline int fsg_common_add_sysfs(struct fsg_common *common, + struct fsg_lun *lun) +{ + int rc; + + rc = device_register(&lun->dev); + if (rc) { + put_device(&lun->dev); + return rc; + } + + rc = device_create_file(&lun->dev, + lun->cdrom + ? &dev_attr_ro_cdrom + : &dev_attr_ro); + if (rc) + goto error; + rc = device_create_file(&lun->dev, + lun->removable + ? &dev_attr_file + : &dev_attr_file_nonremovable); + if (rc) + goto error; + rc = device_create_file(&lun->dev, &dev_attr_nofua); + if (rc) + goto error; + + return 0; + +error: + /* removing nonexistent files is a no-op */ + fsg_common_remove_sysfs(lun); + device_unregister(&lun->dev); + return rc; +} + +int fsg_common_create_lun(struct fsg_common *common, struct fsg_lun_config *cfg, + unsigned int id, const char *name, + const char **name_pfx) +{ + struct fsg_lun *lun; + char *pathbuf, *p; + int rc = -ENOMEM; + + if (!common->nluns || !common->luns) + return -ENODEV; + + if (common->luns[id]) + return -EBUSY; + + if (!cfg->filename && !cfg->removable) { + pr_err("no file given for LUN%d\n", id); + return -EINVAL; + } + + lun = kzalloc(sizeof(*lun), GFP_KERNEL); + if (!lun) + return -ENOMEM; + + lun->name_pfx = name_pfx; + + lun->cdrom = !!cfg->cdrom; + lun->ro = cfg->cdrom || cfg->ro; + lun->initially_ro = lun->ro; + lun->removable = !!cfg->removable; + + if (!common->sysfs) { + /* we DON'T own the name!*/ + lun->name = name; + } else { + lun->dev.release = fsg_lun_release; + lun->dev.parent = &common->gadget->dev; + dev_set_drvdata(&lun->dev, &common->filesem); + dev_set_name(&lun->dev, "%s", name); + lun->name = dev_name(&lun->dev); + + rc = fsg_common_add_sysfs(common, lun); + if (rc) { + pr_info("failed to register LUN%d: %d\n", id, rc); + goto error_sysfs; + } + } + + common->luns[id] = lun; + + if (cfg->filename) { + rc = fsg_lun_open(lun, cfg->filename); + if (rc) + goto error_lun; + } + + pathbuf = kmalloc(PATH_MAX, GFP_KERNEL); + p = "(no medium)"; + if (fsg_lun_is_open(lun)) { + p = "(error)"; + if (pathbuf) { + p = d_path(&lun->filp->f_path, pathbuf, PATH_MAX); + if (IS_ERR(p)) + p = "(error)"; + } + } + pr_info("LUN: %s%s%sfile: %s\n", + lun->removable ? "removable " : "", + lun->ro ? "read only " : "", + lun->cdrom ? "CD-ROM " : "", + p); + kfree(pathbuf); + + return 0; + +error_lun: + if (common->sysfs) { + fsg_common_remove_sysfs(lun); + device_unregister(&lun->dev); + } + fsg_lun_close(lun); + common->luns[id] = NULL; +error_sysfs: + kfree(lun); + return rc; +} +EXPORT_SYMBOL_GPL(fsg_common_create_lun); + +int fsg_common_create_luns(struct fsg_common *common, struct fsg_config *cfg) +{ + char buf[8]; /* enough for 100000000 different numbers, decimal */ + int i, rc; + + for (i = 0; i < common->nluns; ++i) { + snprintf(buf, sizeof(buf), "lun%d", i); + rc = fsg_common_create_lun(common, &cfg->luns[i], i, buf, NULL); + if (rc) + goto fail; + } + + pr_info("Number of LUNs=%d\n", common->nluns); + + return 0; + +fail: + _fsg_common_remove_luns(common, i); + return rc; +} +EXPORT_SYMBOL_GPL(fsg_common_create_luns); + +void fsg_common_set_inquiry_string(struct fsg_common *common, const char *vn, + const char *pn) +{ + int i; + + /* Prepare inquiryString */ + i = get_default_bcdDevice(); + snprintf(common->inquiry_string, sizeof(common->inquiry_string), + "%-8s%-16s%04x", vn ?: "Linux", + /* Assume product name dependent on the first LUN */ + pn ?: ((*common->luns)->cdrom + ? "File-CD Gadget" + : "File-Stor Gadget"), + i); +} +EXPORT_SYMBOL_GPL(fsg_common_set_inquiry_string); + +int fsg_common_run_thread(struct fsg_common *common) +{ + common->state = FSG_STATE_IDLE; + /* Tell the thread to start working */ + common->thread_task = + kthread_create(fsg_main_thread, common, "file-storage"); + if (IS_ERR(common->thread_task)) { + common->state = FSG_STATE_TERMINATED; + return PTR_ERR(common->thread_task); + } + + DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task)); + + wake_up_process(common->thread_task); + + return 0; +} +EXPORT_SYMBOL_GPL(fsg_common_run_thread); + +static void fsg_common_release(struct kref *ref) +{ + struct fsg_common *common = container_of(ref, struct fsg_common, ref); + + /* 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(&common->thread_notifier); + } + + if (likely(common->luns)) { + struct fsg_lun **lun_it = common->luns; + unsigned i = common->nluns; + + /* In error recovery common->nluns may be zero. */ + for (; i; --i, ++lun_it) { + struct fsg_lun *lun = *lun_it; + if (!lun) + continue; + if (common->sysfs) + fsg_common_remove_sysfs(lun); + fsg_lun_close(lun); + if (common->sysfs) + device_unregister(&lun->dev); + kfree(lun); + } + + kfree(common->luns); + } + + _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers); + if (common->free_storage_on_release) + kfree(common); +} + + +/*-------------------------------------------------------------------------*/ + +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; + struct usb_ep *ep; + unsigned max_burst; + int ret; + struct fsg_opts *opts; + + opts = fsg_opts_from_func_inst(f->fi); + if (!opts->no_configfs) { + ret = fsg_common_set_cdev(fsg->common, c->cdev, + fsg->common->can_stall); + if (ret) + return ret; + fsg_common_set_inquiry_string(fsg->common, NULL, NULL); + ret = fsg_common_run_thread(fsg->common); + if (ret) + return ret; + } + + fsg->gadget = gadget; + + /* 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 = fsg->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 = fsg->common; /* claim the endpoint */ + fsg->bulk_out = ep; + + /* 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; + + /* Calculate bMaxBurst, we know packet size is 1024 */ + max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15); + + fsg_ss_bulk_in_desc.bEndpointAddress = + fsg_fs_bulk_in_desc.bEndpointAddress; + fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst; + + fsg_ss_bulk_out_desc.bEndpointAddress = + fsg_fs_bulk_out_desc.bEndpointAddress; + fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst; + + ret = usb_assign_descriptors(f, fsg_fs_function, fsg_hs_function, + fsg_ss_function); + if (ret) + goto autoconf_fail; + + return 0; + +autoconf_fail: + ERROR(fsg, "unable to autoconfigure all endpoints\n"); + return -ENOTSUPP; +} + +/****************************** ALLOCATE FUNCTION *************************/ + +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; + + DBG(fsg, "unbind\n"); + if (fsg->common->fsg == fsg) { + fsg->common->new_fsg = NULL; + raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE); + /* FIXME: make interruptible or killable somehow? */ + wait_event(common->fsg_wait, common->fsg != fsg); + } + + usb_free_all_descriptors(&fsg->function); +} + +static inline struct fsg_lun_opts *to_fsg_lun_opts(struct config_item *item) +{ + return container_of(to_config_group(item), struct fsg_lun_opts, group); +} + +static inline struct fsg_opts *to_fsg_opts(struct config_item *item) +{ + return container_of(to_config_group(item), struct fsg_opts, + func_inst.group); +} + +CONFIGFS_ATTR_STRUCT(fsg_lun_opts); +CONFIGFS_ATTR_OPS(fsg_lun_opts); + +static void fsg_lun_attr_release(struct config_item *item) +{ + struct fsg_lun_opts *lun_opts; + + lun_opts = to_fsg_lun_opts(item); + kfree(lun_opts); +} + +static struct configfs_item_operations fsg_lun_item_ops = { + .release = fsg_lun_attr_release, + .show_attribute = fsg_lun_opts_attr_show, + .store_attribute = fsg_lun_opts_attr_store, +}; + +static ssize_t fsg_lun_opts_file_show(struct fsg_lun_opts *opts, char *page) +{ + struct fsg_opts *fsg_opts; + + fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent); + + return fsg_show_file(opts->lun, &fsg_opts->common->filesem, page); +} + +static ssize_t fsg_lun_opts_file_store(struct fsg_lun_opts *opts, + const char *page, size_t len) +{ + struct fsg_opts *fsg_opts; + + fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent); + + return fsg_store_file(opts->lun, &fsg_opts->common->filesem, page, len); +} + +static struct fsg_lun_opts_attribute fsg_lun_opts_file = + __CONFIGFS_ATTR(file, S_IRUGO | S_IWUSR, fsg_lun_opts_file_show, + fsg_lun_opts_file_store); + +static ssize_t fsg_lun_opts_ro_show(struct fsg_lun_opts *opts, char *page) +{ + return fsg_show_ro(opts->lun, page); +} + +static ssize_t fsg_lun_opts_ro_store(struct fsg_lun_opts *opts, + const char *page, size_t len) +{ + struct fsg_opts *fsg_opts; + + fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent); + + return fsg_store_ro(opts->lun, &fsg_opts->common->filesem, page, len); +} + +static struct fsg_lun_opts_attribute fsg_lun_opts_ro = + __CONFIGFS_ATTR(ro, S_IRUGO | S_IWUSR, fsg_lun_opts_ro_show, + fsg_lun_opts_ro_store); + +static ssize_t fsg_lun_opts_removable_show(struct fsg_lun_opts *opts, + char *page) +{ + return fsg_show_removable(opts->lun, page); +} + +static ssize_t fsg_lun_opts_removable_store(struct fsg_lun_opts *opts, + const char *page, size_t len) +{ + return fsg_store_removable(opts->lun, page, len); +} + +static struct fsg_lun_opts_attribute fsg_lun_opts_removable = + __CONFIGFS_ATTR(removable, S_IRUGO | S_IWUSR, + fsg_lun_opts_removable_show, + fsg_lun_opts_removable_store); + +static ssize_t fsg_lun_opts_cdrom_show(struct fsg_lun_opts *opts, char *page) +{ + return fsg_show_cdrom(opts->lun, page); +} + +static ssize_t fsg_lun_opts_cdrom_store(struct fsg_lun_opts *opts, + const char *page, size_t len) +{ + struct fsg_opts *fsg_opts; + + fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent); + + return fsg_store_cdrom(opts->lun, &fsg_opts->common->filesem, page, + len); +} + +static struct fsg_lun_opts_attribute fsg_lun_opts_cdrom = + __CONFIGFS_ATTR(cdrom, S_IRUGO | S_IWUSR, fsg_lun_opts_cdrom_show, + fsg_lun_opts_cdrom_store); + +static ssize_t fsg_lun_opts_nofua_show(struct fsg_lun_opts *opts, char *page) +{ + return fsg_show_nofua(opts->lun, page); +} + +static ssize_t fsg_lun_opts_nofua_store(struct fsg_lun_opts *opts, + const char *page, size_t len) +{ + return fsg_store_nofua(opts->lun, page, len); +} + +static struct fsg_lun_opts_attribute fsg_lun_opts_nofua = + __CONFIGFS_ATTR(nofua, S_IRUGO | S_IWUSR, fsg_lun_opts_nofua_show, + fsg_lun_opts_nofua_store); + +static struct configfs_attribute *fsg_lun_attrs[] = { + &fsg_lun_opts_file.attr, + &fsg_lun_opts_ro.attr, + &fsg_lun_opts_removable.attr, + &fsg_lun_opts_cdrom.attr, + &fsg_lun_opts_nofua.attr, + NULL, +}; + +static struct config_item_type fsg_lun_type = { + .ct_item_ops = &fsg_lun_item_ops, + .ct_attrs = fsg_lun_attrs, + .ct_owner = THIS_MODULE, +}; + +static struct config_group *fsg_lun_make(struct config_group *group, + const char *name) +{ + struct fsg_lun_opts *opts; + struct fsg_opts *fsg_opts; + struct fsg_lun_config config; + char *num_str; + u8 num; + int ret; + + num_str = strchr(name, '.'); + if (!num_str) { + pr_err("Unable to locate . in LUN.NUMBER\n"); + return ERR_PTR(-EINVAL); + } + num_str++; + + ret = kstrtou8(num_str, 0, &num); + if (ret) + return ERR_PTR(ret); + + fsg_opts = to_fsg_opts(&group->cg_item); + if (num >= FSG_MAX_LUNS) + return ERR_PTR(-ERANGE); + + mutex_lock(&fsg_opts->lock); + if (fsg_opts->refcnt || fsg_opts->common->luns[num]) { + ret = -EBUSY; + goto out; + } + + opts = kzalloc(sizeof(*opts), GFP_KERNEL); + if (!opts) { + ret = -ENOMEM; + goto out; + } + + memset(&config, 0, sizeof(config)); + config.removable = true; + + ret = fsg_common_create_lun(fsg_opts->common, &config, num, name, + (const char **)&group->cg_item.ci_name); + if (ret) { + kfree(opts); + goto out; + } + opts->lun = fsg_opts->common->luns[num]; + opts->lun_id = num; + mutex_unlock(&fsg_opts->lock); + + config_group_init_type_name(&opts->group, name, &fsg_lun_type); + + return &opts->group; +out: + mutex_unlock(&fsg_opts->lock); + return ERR_PTR(ret); +} + +static void fsg_lun_drop(struct config_group *group, struct config_item *item) +{ + struct fsg_lun_opts *lun_opts; + struct fsg_opts *fsg_opts; + + lun_opts = to_fsg_lun_opts(item); + fsg_opts = to_fsg_opts(&group->cg_item); + + mutex_lock(&fsg_opts->lock); + if (fsg_opts->refcnt) { + struct config_item *gadget; + + gadget = group->cg_item.ci_parent->ci_parent; + unregister_gadget_item(gadget); + } + + fsg_common_remove_lun(lun_opts->lun, fsg_opts->common->sysfs); + fsg_opts->common->luns[lun_opts->lun_id] = NULL; + lun_opts->lun_id = 0; + mutex_unlock(&fsg_opts->lock); + + config_item_put(item); +} + +CONFIGFS_ATTR_STRUCT(fsg_opts); +CONFIGFS_ATTR_OPS(fsg_opts); + +static void fsg_attr_release(struct config_item *item) +{ + struct fsg_opts *opts = to_fsg_opts(item); + + usb_put_function_instance(&opts->func_inst); +} + +static struct configfs_item_operations fsg_item_ops = { + .release = fsg_attr_release, + .show_attribute = fsg_opts_attr_show, + .store_attribute = fsg_opts_attr_store, +}; + +static ssize_t fsg_opts_stall_show(struct fsg_opts *opts, char *page) +{ + int result; + + mutex_lock(&opts->lock); + result = sprintf(page, "%d", opts->common->can_stall); + mutex_unlock(&opts->lock); + + return result; +} + +static ssize_t fsg_opts_stall_store(struct fsg_opts *opts, const char *page, + size_t len) +{ + int ret; + bool stall; + + mutex_lock(&opts->lock); + + if (opts->refcnt) { + mutex_unlock(&opts->lock); + return -EBUSY; + } + + ret = strtobool(page, &stall); + if (!ret) { + opts->common->can_stall = stall; + ret = len; + } + + mutex_unlock(&opts->lock); + + return ret; +} + +static struct fsg_opts_attribute fsg_opts_stall = + __CONFIGFS_ATTR(stall, S_IRUGO | S_IWUSR, fsg_opts_stall_show, + fsg_opts_stall_store); + +#ifdef CONFIG_USB_GADGET_DEBUG_FILES +static ssize_t fsg_opts_num_buffers_show(struct fsg_opts *opts, char *page) +{ + int result; + + mutex_lock(&opts->lock); + result = sprintf(page, "%d", opts->common->fsg_num_buffers); + mutex_unlock(&opts->lock); + + return result; +} + +static ssize_t fsg_opts_num_buffers_store(struct fsg_opts *opts, + const char *page, size_t len) +{ + int ret; + u8 num; + + mutex_lock(&opts->lock); + if (opts->refcnt) { + ret = -EBUSY; + goto end; + } + ret = kstrtou8(page, 0, &num); + if (ret) + goto end; + + ret = fsg_num_buffers_validate(num); + if (ret) + goto end; + + fsg_common_set_num_buffers(opts->common, num); + ret = len; + +end: + mutex_unlock(&opts->lock); + return ret; +} + +static struct fsg_opts_attribute fsg_opts_num_buffers = + __CONFIGFS_ATTR(num_buffers, S_IRUGO | S_IWUSR, + fsg_opts_num_buffers_show, + fsg_opts_num_buffers_store); + +#endif + +static struct configfs_attribute *fsg_attrs[] = { + &fsg_opts_stall.attr, +#ifdef CONFIG_USB_GADGET_DEBUG_FILES + &fsg_opts_num_buffers.attr, +#endif + NULL, +}; + +static struct configfs_group_operations fsg_group_ops = { + .make_group = fsg_lun_make, + .drop_item = fsg_lun_drop, +}; + +static struct config_item_type fsg_func_type = { + .ct_item_ops = &fsg_item_ops, + .ct_group_ops = &fsg_group_ops, + .ct_attrs = fsg_attrs, + .ct_owner = THIS_MODULE, +}; + +static void fsg_free_inst(struct usb_function_instance *fi) +{ + struct fsg_opts *opts; + + opts = fsg_opts_from_func_inst(fi); + fsg_common_put(opts->common); + kfree(opts); +} + +static struct usb_function_instance *fsg_alloc_inst(void) +{ + struct fsg_opts *opts; + struct fsg_lun_config config; + int rc; + + opts = kzalloc(sizeof(*opts), GFP_KERNEL); + if (!opts) + return ERR_PTR(-ENOMEM); + mutex_init(&opts->lock); + opts->func_inst.free_func_inst = fsg_free_inst; + opts->common = fsg_common_setup(opts->common); + if (IS_ERR(opts->common)) { + rc = PTR_ERR(opts->common); + goto release_opts; + } + rc = fsg_common_set_nluns(opts->common, FSG_MAX_LUNS); + if (rc) + goto release_opts; + + rc = fsg_common_set_num_buffers(opts->common, + CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS); + if (rc) + goto release_luns; + + pr_info(FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n"); + + memset(&config, 0, sizeof(config)); + config.removable = true; + rc = fsg_common_create_lun(opts->common, &config, 0, "lun.0", + (const char **)&opts->func_inst.group.cg_item.ci_name); + opts->lun0.lun = opts->common->luns[0]; + opts->lun0.lun_id = 0; + config_group_init_type_name(&opts->lun0.group, "lun.0", &fsg_lun_type); + opts->default_groups[0] = &opts->lun0.group; + opts->func_inst.group.default_groups = opts->default_groups; + + config_group_init_type_name(&opts->func_inst.group, "", &fsg_func_type); + + return &opts->func_inst; + +release_luns: + kfree(opts->common->luns); +release_opts: + kfree(opts); + return ERR_PTR(rc); +} + +static void fsg_free(struct usb_function *f) +{ + struct fsg_dev *fsg; + struct fsg_opts *opts; + + fsg = container_of(f, struct fsg_dev, function); + opts = container_of(f->fi, struct fsg_opts, func_inst); + + mutex_lock(&opts->lock); + opts->refcnt--; + mutex_unlock(&opts->lock); + + kfree(fsg); +} + +static struct usb_function *fsg_alloc(struct usb_function_instance *fi) +{ + struct fsg_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 (unlikely(!fsg)) + return ERR_PTR(-ENOMEM); + + mutex_lock(&opts->lock); + opts->refcnt++; + mutex_unlock(&opts->lock); + fsg->function.name = FSG_DRIVER_DESC; + fsg->function.bind = fsg_bind; + fsg->function.unbind = fsg_unbind; + fsg->function.setup = fsg_setup; + fsg->function.set_alt = fsg_set_alt; + fsg->function.disable = fsg_disable; + fsg->function.free_func = fsg_free; + + fsg->common = common; + + return &fsg->function; +} + +DECLARE_USB_FUNCTION_INIT(mass_storage, fsg_alloc_inst, fsg_alloc); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Michal Nazarewicz"); + +/************************* Module parameters *************************/ + + +void fsg_config_from_params(struct fsg_config *cfg, + const struct fsg_module_parameters *params, + unsigned int fsg_num_buffers) +{ + struct fsg_lun_config *lun; + unsigned i; + + /* Configure LUNs */ + cfg->nluns = + min(params->luns ?: (params->file_count ?: 1u), + (unsigned)FSG_MAX_LUNS); + for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) { + lun->ro = !!params->ro[i]; + lun->cdrom = !!params->cdrom[i]; + lun->removable = !!params->removable[i]; + lun->filename = + params->file_count > i && params->file[i][0] + ? params->file[i] + : NULL; + } + + /* Let MSF use defaults */ + cfg->vendor_name = NULL; + cfg->product_name = NULL; + + cfg->ops = NULL; + cfg->private_data = NULL; + + /* Finalise */ + cfg->can_stall = params->stall; + cfg->fsg_num_buffers = fsg_num_buffers; +} +EXPORT_SYMBOL_GPL(fsg_config_from_params); + |