android/android_kernel_xiaomi_sm8450
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[PATCH] USB: File-Storage gadget: use the kthread API

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This patch (as566) converts the File-Storage gadget over to the kthread
API.  The new code doesn't use kthread_stop because the control thread
needs to terminate asynchronously when it receives a signal.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

 drivers/usb/gadget/file_storage.c |   32 +++++++++++++-------------------
 1 file changed, 13 insertions(+), 19 deletions(-)
This commit is contained in:
Alan Stern
2005-09-26 16:12:02 -04:00
committed by Greg Kroah-Hartman
parent dabb592816
commit 22efcf4ade
1 changed files with 13 additions and 19 deletions
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32
drivers/usb/gadget/file_storage.c
View File

@ -224,6 +224,7 @@
#include <linux/fs.h> #include <linux/fs.h>
#include <linux/init.h> #include <linux/init.h>
#include <linux/kernel.h> #include <linux/kernel.h>
#include <linux/kthread.h>
#include <linux/limits.h> #include <linux/limits.h>
#include <linux/list.h> #include <linux/list.h>
#include <linux/module.h> #include <linux/module.h>
@ -669,7 +670,6 @@ struct fsg_dev {
wait_queue_head_t thread_wqh; wait_queue_head_t thread_wqh;
int thread_wakeup_needed; int thread_wakeup_needed;
struct completion thread_notifier; struct completion thread_notifier;
int thread_pid;
struct task_struct *thread_task; struct task_struct *thread_task;
sigset_t thread_signal_mask; sigset_t thread_signal_mask;
@ -1084,7 +1084,6 @@ static void wakeup_thread(struct fsg_dev *fsg)
static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state) static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state)
{ {
unsigned long flags; unsigned long flags;
struct task_struct *thread_task;
/* Do nothing if a higher-priority exception is already in progress. /* Do nothing if a higher-priority exception is already in progress.
* If a lower-or-equal priority exception is in progress, preempt it * If a lower-or-equal priority exception is in progress, preempt it
@ -1093,9 +1092,9 @@ static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state)
if (fsg->state <= new_state) { if (fsg->state <= new_state) {
fsg->exception_req_tag = fsg->ep0_req_tag; fsg->exception_req_tag = fsg->ep0_req_tag;
fsg->state = new_state; fsg->state = new_state;
thread_task = fsg->thread_task; if (fsg->thread_task)
if (thread_task) send_sig_info(SIGUSR1, SEND_SIG_FORCED,
send_sig_info(SIGUSR1, SEND_SIG_FORCED, thread_task); fsg->thread_task);
} }
spin_unlock_irqrestore(&fsg->lock, flags); spin_unlock_irqrestore(&fsg->lock, flags);
} }
@ -3383,11 +3382,6 @@ static int fsg_main_thread(void *fsg_)
{ {
struct fsg_dev *fsg = (struct fsg_dev *) fsg_; 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 /* Allow the thread to be killed by a signal, but set the signal mask
* to block everything but INT, TERM, KILL, and USR1. */ * to block everything but INT, TERM, KILL, and USR1. */
siginitsetinv(&fsg->thread_signal_mask, sigmask(SIGINT) | siginitsetinv(&fsg->thread_signal_mask, sigmask(SIGINT) |
@ -3400,9 +3394,6 @@ static int fsg_main_thread(void *fsg_)
* that expects a __user pointer and it will work okay. */ * that expects a __user pointer and it will work okay. */
set_fs(get_ds()); set_fs(get_ds());
/* Wait for the gadget registration to finish up */
wait_for_completion(&fsg->thread_notifier);
/* The main loop */ /* The main loop */
while (fsg->state != FSG_STATE_TERMINATED) { while (fsg->state != FSG_STATE_TERMINATED) {
if (exception_in_progress(fsg) || signal_pending(current)) { if (exception_in_progress(fsg) || signal_pending(current)) {
@ -3440,8 +3431,9 @@ static int fsg_main_thread(void *fsg_)
spin_unlock_irq(&fsg->lock); spin_unlock_irq(&fsg->lock);
} }
spin_lock_irq(&fsg->lock);
fsg->thread_task = NULL; fsg->thread_task = NULL;
flush_signals(current); spin_unlock_irq(&fsg->lock);
/* In case we are exiting because of a signal, unregister the /* In case we are exiting because of a signal, unregister the
* gadget driver and close the backing file. */ * gadget driver and close the backing file. */
@ -3959,10 +3951,12 @@ static int __init fsg_bind(struct usb_gadget *gadget)
sprintf(&serial[i], "%02X", c); sprintf(&serial[i], "%02X", c);
} }
if ((rc = kernel_thread(fsg_main_thread, fsg, (CLONE_VM | CLONE_FS | fsg->thread_task = kthread_create(fsg_main_thread, fsg,
CLONE_FILES))) < 0) "file-storage-gadget");
if (IS_ERR(fsg->thread_task)) {
rc = PTR_ERR(fsg->thread_task);
goto out; goto out;
fsg->thread_pid = rc; }
INFO(fsg, DRIVER_DESC ", version: " DRIVER_VERSION "\n"); INFO(fsg, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
INFO(fsg, "Number of LUNs=%d\n", fsg->nluns); INFO(fsg, "Number of LUNs=%d\n", fsg->nluns);
@ -3994,7 +3988,7 @@ static int __init fsg_bind(struct usb_gadget *gadget)
DBG(fsg, "removable=%d, stall=%d, buflen=%u\n", DBG(fsg, "removable=%d, stall=%d, buflen=%u\n",
mod_data.removable, mod_data.can_stall, mod_data.removable, mod_data.can_stall,
mod_data.buflen); 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);
return 0; return 0;
autoconf_fail: autoconf_fail:
@ -4093,7 +4087,7 @@ static int __init fsg_init(void)
set_bit(REGISTERED, &fsg->atomic_bitflags); set_bit(REGISTERED, &fsg->atomic_bitflags);
/* Tell the thread to start working */ /* Tell the thread to start working */
complete(&fsg->thread_notifier); wake_up_process(fsg->thread_task);
return 0; return 0;
} }
module_init(fsg_init); module_init(fsg_init);