#include <linux/fs.h>
#include <linux/init.h>
#include <linux/kernel.h>
+#include <linux/kref.h>
+#include <linux/kthread.h>
#include <linux/limits.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/suspend.h>
#include <linux/utsname.h>
-#include <linux/wait.h>
#include <linux/usb_ch9.h>
#include <linux/usb_gadget.h>
#define DRIVER_DESC "File-backed Storage Gadget"
#define DRIVER_NAME "g_file_storage"
-#define DRIVER_VERSION "20 October 2004"
+#define DRIVER_VERSION "28 November 2005"
static const char longname[] = DRIVER_DESC;
static const char shortname[] = DRIVER_NAME;
#define MAX_LUNS 8
/* Arggh! There should be a module_param_array_named macro! */
-static char *file[MAX_LUNS] = {NULL, };
-static int ro[MAX_LUNS] = {0, };
+static char *file[MAX_LUNS];
+static int ro[MAX_LUNS];
static struct {
int num_filenames;
struct fsg_buffhd {
void *buf;
dma_addr_t dma;
- volatile enum fsg_buffer_state state;
+ enum fsg_buffer_state state;
struct fsg_buffhd *next;
/* The NetChip 2280 is faster, and handles some protocol faults
unsigned int bulk_out_intended_length;
struct usb_request *inreq;
- volatile int inreq_busy;
+ int inreq_busy;
struct usb_request *outreq;
- volatile int outreq_busy;
+ int outreq_busy;
};
enum fsg_state {
/* filesem protects: backing files in use */
struct rw_semaphore filesem;
+ /* reference counting: wait until all LUNs are released */
+ struct kref ref;
+
struct usb_ep *ep0; // Handy copy of gadget->ep0
struct usb_request *ep0req; // For control responses
- volatile unsigned int ep0_req_tag;
+ unsigned int ep0_req_tag;
const char *ep0req_name;
struct usb_request *intreq; // For interrupt responses
- volatile int intreq_busy;
+ int intreq_busy;
struct fsg_buffhd *intr_buffhd;
unsigned int bulk_out_maxpacket;
struct fsg_buffhd *next_buffhd_to_drain;
struct fsg_buffhd buffhds[NUM_BUFFERS];
- wait_queue_head_t thread_wqh;
int thread_wakeup_needed;
struct completion thread_notifier;
- int thread_pid;
struct task_struct *thread_task;
sigset_t thread_signal_mask;
unsigned int nluns;
struct lun *luns;
struct lun *curlun;
- struct completion lun_released;
};
typedef void (*fsg_routine_t)(struct fsg_dev *);
/* These routines may be called in process context or in_irq */
+/* Caller must hold fsg->lock */
static void wakeup_thread(struct fsg_dev *fsg)
{
/* Tell the main thread that something has happened */
fsg->thread_wakeup_needed = 1;
- wake_up_all(&fsg->thread_wqh);
+ if (fsg->thread_task)
+ wake_up_process(fsg->thread_task);
}
static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state)
{
unsigned long flags;
- struct task_struct *thread_task;
/* Do nothing if a higher-priority exception is already in progress.
* If a lower-or-equal priority exception is in progress, preempt it
if (fsg->state <= new_state) {
fsg->exception_req_tag = fsg->ep0_req_tag;
fsg->state = new_state;
- thread_task = fsg->thread_task;
- if (thread_task)
- send_sig_info(SIGUSR1, SEND_SIG_FORCED, thread_task);
+ if (fsg->thread_task)
+ send_sig_info(SIGUSR1, SEND_SIG_FORCED,
+ fsg->thread_task);
}
spin_unlock_irqrestore(&fsg->lock, flags);
}
usb_ep_fifo_flush(ep);
/* Hold the lock while we update the request and buffer states */
+ smp_wmb();
spin_lock(&fsg->lock);
bh->inreq_busy = 0;
bh->state = BUF_STATE_EMPTY;
- spin_unlock(&fsg->lock);
wakeup_thread(fsg);
+ spin_unlock(&fsg->lock);
}
static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
usb_ep_fifo_flush(ep);
/* Hold the lock while we update the request and buffer states */
+ smp_wmb();
spin_lock(&fsg->lock);
bh->outreq_busy = 0;
bh->state = BUF_STATE_FULL;
- spin_unlock(&fsg->lock);
wakeup_thread(fsg);
+ spin_unlock(&fsg->lock);
}
usb_ep_fifo_flush(ep);
/* Hold the lock while we update the request and buffer states */
+ smp_wmb();
spin_lock(&fsg->lock);
fsg->intreq_busy = 0;
bh->state = BUF_STATE_EMPTY;
- spin_unlock(&fsg->lock);
wakeup_thread(fsg);
+ spin_unlock(&fsg->lock);
}
#else
fsg->cbbuf_cmnd_size = req->actual;
memcpy(fsg->cbbuf_cmnd, req->buf, fsg->cbbuf_cmnd_size);
- spin_unlock(&fsg->lock);
wakeup_thread(fsg);
+ spin_unlock(&fsg->lock);
}
#else
/* 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, volatile int *pbusy,
- volatile enum fsg_buffer_state *state)
+ struct usb_request *req, int *pbusy,
+ enum fsg_buffer_state *state)
{
int rc;
dump_msg(fsg, "bulk-in", req->buf, req->length);
else if (ep == fsg->intr_in)
dump_msg(fsg, "intr-in", req->buf, req->length);
+
+ spin_lock_irq(&fsg->lock);
*pbusy = 1;
*state = BUF_STATE_BUSY;
+ spin_unlock_irq(&fsg->lock);
rc = usb_ep_queue(ep, req, GFP_KERNEL);
if (rc != 0) {
*pbusy = 0;
static int sleep_thread(struct fsg_dev *fsg)
{
- int rc;
+ int rc = 0;
/* Wait until a signal arrives or we are woken up */
- rc = wait_event_interruptible(fsg->thread_wqh,
- fsg->thread_wakeup_needed);
+ for (;;) {
+ try_to_freeze();
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (signal_pending(current)) {
+ rc = -EINTR;
+ break;
+ }
+ if (fsg->thread_wakeup_needed)
+ break;
+ schedule();
+ }
+ __set_current_state(TASK_RUNNING);
fsg->thread_wakeup_needed = 0;
- try_to_freeze();
- return (rc ? -EINTR : 0);
+ return rc;
}
if (bh->state == BUF_STATE_EMPTY && !get_some_more)
break; // We stopped early
if (bh->state == BUF_STATE_FULL) {
+ smp_rmb();
fsg->next_buffhd_to_drain = bh->next;
bh->state = BUF_STATE_EMPTY;
return -EINVAL;
inode = filp->f_dentry->d_inode;
- down(&inode->i_sem);
+ mutex_lock(&inode->i_mutex);
current->flags |= PF_SYNCWRITE;
rc = filemap_fdatawrite(inode->i_mapping);
err = filp->f_op->fsync(filp, filp->f_dentry, 1);
if (!rc)
rc = err;
current->flags &= ~PF_SYNCWRITE;
- up(&inode->i_sem);
+ mutex_unlock(&inode->i_mutex);
VLDBG(curlun, "fdatasync -> %d\n", rc);
return rc;
}
/* Throw away the data in a filled buffer */
if (bh->state == BUF_STATE_FULL) {
+ smp_rmb();
bh->state = BUF_STATE_EMPTY;
fsg->next_buffhd_to_drain = bh->next;
if ((rc = sleep_thread(fsg)) != 0)
return rc;
}
+ smp_rmb();
rc = received_cbw(fsg, bh);
bh->state = BUF_STATE_EMPTY;
{
struct fsg_dev *fsg = (struct fsg_dev *) fsg_;
- fsg->thread_task = current;
-
- /* Release all our userspace resources */
- daemonize("file-storage-gadget");
-
/* Allow the thread to be killed by a signal, but set the signal mask
* to block everything but INT, TERM, KILL, and USR1. */
siginitsetinv(&fsg->thread_signal_mask, sigmask(SIGINT) |
* that expects a __user pointer and it will work okay. */
set_fs(get_ds());
- /* Wait for the gadget registration to finish up */
- wait_for_completion(&fsg->thread_notifier);
-
/* The main loop */
while (fsg->state != FSG_STATE_TERMINATED) {
if (exception_in_progress(fsg) || signal_pending(current)) {
spin_unlock_irq(&fsg->lock);
}
+ spin_lock_irq(&fsg->lock);
fsg->thread_task = NULL;
- flush_signals(current);
+ spin_unlock_irq(&fsg->lock);
/* In case we are exiting because of a signal, unregister the
* gadget driver and close the backing file. */
/*-------------------------------------------------------------------------*/
+static void fsg_release(struct kref *ref)
+{
+ struct fsg_dev *fsg = container_of(ref, struct fsg_dev, ref);
+
+ kfree(fsg->luns);
+ kfree(fsg);
+}
+
static void lun_release(struct device *dev)
{
struct fsg_dev *fsg = (struct fsg_dev *) dev_get_drvdata(dev);
- complete(&fsg->lun_released);
+ kref_put(&fsg->ref, fsg_release);
}
static void fsg_unbind(struct usb_gadget *gadget)
clear_bit(REGISTERED, &fsg->atomic_bitflags);
/* Unregister the sysfs attribute files and the LUNs */
- init_completion(&fsg->lun_released);
for (i = 0; i < fsg->nluns; ++i) {
curlun = &fsg->luns[i];
if (curlun->registered) {
device_remove_file(&curlun->dev, &dev_attr_ro);
device_remove_file(&curlun->dev, &dev_attr_file);
device_unregister(&curlun->dev);
- wait_for_completion(&fsg->lun_released);
curlun->registered = 0;
}
}
/* Create the LUNs, open their backing files, and register the
* LUN devices in sysfs. */
- fsg->luns = kmalloc(i * sizeof(struct lun), GFP_KERNEL);
+ fsg->luns = kzalloc(i * sizeof(struct lun), GFP_KERNEL);
if (!fsg->luns) {
rc = -ENOMEM;
goto out;
}
- memset(fsg->luns, 0, i * sizeof(struct lun));
fsg->nluns = i;
for (i = 0; i < fsg->nluns; ++i) {
curlun->dev.release = lun_release;
device_create_file(&curlun->dev, &dev_attr_ro);
device_create_file(&curlun->dev, &dev_attr_file);
+ kref_get(&fsg->ref);
}
if (file[i] && *file[i]) {
sprintf(&serial[i], "%02X", c);
}
- if ((rc = kernel_thread(fsg_main_thread, fsg, (CLONE_VM | CLONE_FS |
- CLONE_FILES))) < 0)
+ fsg->thread_task = kthread_create(fsg_main_thread, fsg,
+ "file-storage-gadget");
+ if (IS_ERR(fsg->thread_task)) {
+ rc = PTR_ERR(fsg->thread_task);
goto out;
- fsg->thread_pid = rc;
+ }
INFO(fsg, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
INFO(fsg, "Number of LUNs=%d\n", fsg->nluns);
DBG(fsg, "removable=%d, stall=%d, buflen=%u\n",
mod_data.removable, mod_data.can_stall,
mod_data.buflen);
- DBG(fsg, "I/O thread pid: %d\n", fsg->thread_pid);
+ DBG(fsg, "I/O thread pid: %d\n", fsg->thread_task->pid);
+
+ set_bit(REGISTERED, &fsg->atomic_bitflags);
+
+ /* Tell the thread to start working */
+ wake_up_process(fsg->thread_task);
return 0;
autoconf_fail:
.driver = {
.name = (char *) shortname,
+ .owner = THIS_MODULE,
// .release = ...
// .suspend = ...
// .resume = ...
{
struct fsg_dev *fsg;
- fsg = kmalloc(sizeof *fsg, GFP_KERNEL);
+ fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
if (!fsg)
return -ENOMEM;
- memset(fsg, 0, sizeof *fsg);
spin_lock_init(&fsg->lock);
init_rwsem(&fsg->filesem);
- init_waitqueue_head(&fsg->thread_wqh);
+ kref_init(&fsg->ref);
init_completion(&fsg->thread_notifier);
the_fsg = fsg;
}
-static void fsg_free(struct fsg_dev *fsg)
-{
- kfree(fsg->luns);
- kfree(fsg);
-}
-
-
static int __init fsg_init(void)
{
int rc;
if ((rc = fsg_alloc()) != 0)
return rc;
fsg = the_fsg;
- if ((rc = usb_gadget_register_driver(&fsg_driver)) != 0) {
- fsg_free(fsg);
- return rc;
- }
- set_bit(REGISTERED, &fsg->atomic_bitflags);
-
- /* Tell the thread to start working */
- complete(&fsg->thread_notifier);
- return 0;
+ if ((rc = usb_gadget_register_driver(&fsg_driver)) != 0)
+ kref_put(&fsg->ref, fsg_release);
+ return rc;
}
module_init(fsg_init);
wait_for_completion(&fsg->thread_notifier);
close_all_backing_files(fsg);
- fsg_free(fsg);
+ kref_put(&fsg->ref, fsg_release);
}
module_exit(fsg_cleanup);
projects / cascardo / linux.git / blobdiff