redonkable/remarkable-linux
redonkable/remarkable-linux
1
0
Fork 0
Code Releases Activity

[media] lirc_dev: rework storage for cdev data

Browse source 
Fixes an oops when an lirc driver that doesn't provide its own fops is
unplugged while the lirc cdev is open. Tested with lirc_igorplugusb,
with a special thanks to Timo Boettcher for providing the test hardware.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Jarod Wilson 2010-10-18 18:39:20 -03:00 committed by Mauro Carvalho Chehab
parent 09c8dd8de6
commit c1cbb7029e
1 changed files with 23 additions and 17 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

40
drivers/media/IR/lirc_dev.c
View file

@ -58,13 +58,12 @@ struct irctl {
struct task_struct *task;
long jiffies_to_wait;
struct cdev cdev;
};
static DEFINE_MUTEX(lirc_dev_lock);
static struct irctl *irctls[MAX_IRCTL_DEVICES];
static struct cdev cdevs[MAX_IRCTL_DEVICES];
/* Only used for sysfs but defined to void otherwise */
static struct class *lirc_class;
@ -170,19 +169,20 @@ static int lirc_cdev_add(struct irctl *ir)
{
int retval;
struct lirc_driver *d = &ir->d;
struct cdev *cdev = &cdevs[d->minor];
if (d->fops) {
cdev_init(&ir->cdev, d->fops);
ir->cdev.owner = d->owner;
cdev_init(cdev, d->fops);
cdev->owner = d->owner;
} else {
cdev_init(&ir->cdev, &lirc_dev_fops);
ir->cdev.owner = THIS_MODULE;
cdev_init(cdev, &lirc_dev_fops);
cdev->owner = THIS_MODULE;
}
kobject_set_name(&ir->cdev.kobj, "lirc%d", d->minor);
kobject_set_name(&cdev->kobj, "lirc%d", d->minor);
retval = cdev_add(&ir->cdev, MKDEV(MAJOR(lirc_base_dev), d->minor), 1);
retval = cdev_add(cdev, MKDEV(MAJOR(lirc_base_dev), d->minor), 1);
if (retval)
kobject_put(&ir->cdev.kobj);
kobject_put(&cdev->kobj);
return retval;
}
@ -363,6 +363,7 @@ EXPORT_SYMBOL(lirc_register_driver);
int lirc_unregister_driver(int minor)
{
struct irctl *ir;
struct cdev *cdev;
if (minor < 0 || minor >= MAX_IRCTL_DEVICES) {
printk(KERN_ERR "lirc_dev: %s: minor (%d) must be between "
@ -377,6 +378,8 @@ int lirc_unregister_driver(int minor)
return -ENOENT;
}
cdev = &cdevs[minor];
mutex_lock(&lirc_dev_lock);
if (ir->d.minor != minor) {
@ -400,11 +403,11 @@ int lirc_unregister_driver(int minor)
wake_up_interruptible(&ir->buf->wait_poll);
mutex_lock(&ir->irctl_lock);
ir->d.set_use_dec(ir->d.data);
module_put(ir->cdev.owner);
module_put(cdev->owner);
mutex_unlock(&ir->irctl_lock);
} else {
lirc_irctl_cleanup(ir);
cdev_del(&ir->cdev);
cdev_del(cdev);
kfree(ir);
irctls[minor] = NULL;
}
@ -418,6 +421,7 @@ EXPORT_SYMBOL(lirc_unregister_driver);
int lirc_dev_fop_open(struct inode *inode, struct file *file)
{
struct irctl *ir;
struct cdev *cdev;
int retval = 0;
if (iminor(inode) >= MAX_IRCTL_DEVICES) {
@ -447,13 +451,14 @@ int lirc_dev_fop_open(struct inode *inode, struct file *file)
goto error;
}
if (try_module_get(ir->cdev.owner)) {
++ir->open;
cdev = &cdevs[iminor(inode)];
if (try_module_get(cdev->owner)) {
ir->open++;
retval = ir->d.set_use_inc(ir->d.data);
if (retval) {
module_put(ir->cdev.owner);
--ir->open;
module_put(cdev->owner);
ir->open--;
} else {
lirc_buffer_clear(ir->buf);
}
@ -475,6 +480,7 @@ EXPORT_SYMBOL(lirc_dev_fop_open);
int lirc_dev_fop_close(struct inode *inode, struct file *file)
{
struct irctl *ir = irctls[iminor(inode)];
struct cdev *cdev = &cdevs[iminor(inode)];
if (!ir) {
printk(KERN_ERR "%s: called with invalid irctl\n", __func__);
@ -488,10 +494,10 @@ int lirc_dev_fop_close(struct inode *inode, struct file *file)
ir->open--;
if (ir->attached) {
ir->d.set_use_dec(ir->d.data);
module_put(ir->cdev.owner);
module_put(cdev->owner);
} else {
lirc_irctl_cleanup(ir);
cdev_del(&ir->cdev);
cdev_del(cdev);
irctls[ir->d.minor] = NULL;
kfree(ir);
}