diff options
| author | Mike Isely <isely@pobox.com> | 2008-04-22 14:45:44 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@infradead.org> | 2008-04-24 14:07:48 -0300 |
| commit | c4a8828ddbf5fb445d2679ab006d5743540fc41a (patch) | |
| tree | 2b17fa77218b812f164f1d897dfe1015d98d2510 /drivers/media/video/pvrusb2/pvrusb2-hdw.c | |
| parent | ee9ca4b24f03b4da04cae1a24ea445ceb8a1f3d2 (diff) | |
V4L/DVB (7319): pvrusb2: Close potential race condition during initialization
There is a callback that is issued to into pvr2_context from pvr2_hdw
after initialization is done. There was a probability that this
callback could get missed. Fixed.
Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Diffstat (limited to 'drivers/media/video/pvrusb2/pvrusb2-hdw.c')
| -rw-r--r-- | drivers/media/video/pvrusb2/pvrusb2-hdw.c | 31 |
1 files changed, 17 insertions, 14 deletions
diff --git a/drivers/media/video/pvrusb2/pvrusb2-hdw.c b/drivers/media/video/pvrusb2/pvrusb2-hdw.c index c51c5cef82d..f2d2677936b 100644 --- a/drivers/media/video/pvrusb2/pvrusb2-hdw.c +++ b/drivers/media/video/pvrusb2/pvrusb2-hdw.c @@ -1813,8 +1813,23 @@ static void pvr2_hdw_setup(struct pvr2_hdw *hdw) } -/* Create and return a structure for interacting with the underlying - hardware */ +/* Perform second stage initialization. Set callback pointer first so that + we can avoid a possible initialization race (if the kernel thread runs + before the callback has been set). */ +void pvr2_hdw_initialize(struct pvr2_hdw *hdw, + void (*callback_func)(void *), + void *callback_data) +{ + LOCK_TAKE(hdw->big_lock); do { + hdw->state_data = callback_data; + hdw->state_func = callback_func; + } while (0); LOCK_GIVE(hdw->big_lock); + queue_work(hdw->workqueue,&hdw->workinit); +} + + +/* Create, set up, and return a structure for interacting with the + underlying hardware. */ struct pvr2_hdw *pvr2_hdw_create(struct usb_interface *intf, const struct usb_device_id *devid) { @@ -2039,7 +2054,6 @@ struct pvr2_hdw *pvr2_hdw_create(struct usb_interface *intf, mutex_init(&hdw->ctl_lock_mutex); mutex_init(&hdw->big_lock_mutex); - queue_work(hdw->workqueue,&hdw->workinit); return hdw; fail: if (hdw) { @@ -2521,17 +2535,6 @@ static int pvr2_hdw_wait(struct pvr2_hdw *hdw,int state) } -void pvr2_hdw_set_state_callback(struct pvr2_hdw *hdw, - void (*callback_func)(void *), - void *callback_data) -{ - LOCK_TAKE(hdw->big_lock); do { - hdw->state_data = callback_data; - hdw->state_func = callback_func; - } while (0); LOCK_GIVE(hdw->big_lock); -} - - /* Return name for this driver instance */ const char *pvr2_hdw_get_driver_name(struct pvr2_hdw *hdw) { |