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authorDmitry Torokhov <dtor_core@ameritech.net>2005-05-29 11:29:52 +0400
committerDmitry Torokhov <dtor_core@ameritech.net>2005-05-29 11:29:52 +0400
commit8b1a198bf14d59b67e47dc7b133ec5ea443fb40d (patch)
tree11d80109ddc2f61de6a75a37941346100a67a0d1 /drivers/input/joystick/amijoy.c
parentaf246041277674854383cf91b8f0b01217b521e8 (diff)
downloadlinux-8b1a198bf14d59b67e47dc7b133ec5ea443fb40d.tar.xz
Input: fix open/close races in joystick drivers - add a semaphore
to the ones that register more than one input device. Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Diffstat (limited to 'drivers/input/joystick/amijoy.c')
-rw-r--r--drivers/input/joystick/amijoy.c29
1 files changed, 16 insertions, 13 deletions
diff --git a/drivers/input/joystick/amijoy.c b/drivers/input/joystick/amijoy.c
index cf36ca9b92f3..033456bb9fe0 100644
--- a/drivers/input/joystick/amijoy.c
+++ b/drivers/input/joystick/amijoy.c
@@ -51,7 +51,8 @@ MODULE_PARM_DESC(map, "Map of attached joysticks in form of <a>,<b> (default is
__obsolete_setup("amijoy=");
-static int amijoy_used[2] = { 0, 0 };
+static int amijoy_used;
+static DECLARE_MUTEX(amijoy_sem);
static struct input_dev amijoy_dev[2];
static char *amijoy_phys[2] = { "amijoy/input0", "amijoy/input1" };
@@ -84,26 +85,30 @@ static irqreturn_t amijoy_interrupt(int irq, void *dummy, struct pt_regs *fp)
static int amijoy_open(struct input_dev *dev)
{
- int *used = dev->private;
+ int err;
- if ((*used)++)
- return 0;
+ err = down_interruptible(&amijoy_sem);
+ if (err)
+ return err;
- if (request_irq(IRQ_AMIGA_VERTB, amijoy_interrupt, 0, "amijoy", amijoy_interrupt)) {
- (*used)--;
+ if (!amijoy_used && request_irq(IRQ_AMIGA_VERTB, amijoy_interrupt, 0, "amijoy", amijoy_interrupt)) {
printk(KERN_ERR "amijoy.c: Can't allocate irq %d\n", IRQ_AMIGA_VERTB);
- return -EBUSY;
+ err = -EBUSY;
+ goto out;
}
- return 0;
+ amijoy_used++;
+out:
+ up(&amijoy_sem);
+ return err;
}
static void amijoy_close(struct input_dev *dev)
{
- int *used = dev->private;
-
- if (!--(*used))
+ down(&amijoysem);
+ if (!--amijoy_used)
free_irq(IRQ_AMIGA_VERTB, amijoy_interrupt);
+ up(&amijoy_sem);
}
static int __init amijoy_init(void)
@@ -138,8 +143,6 @@ static int __init amijoy_init(void)
amijoy_dev[i].id.product = 0x0003;
amijoy_dev[i].id.version = 0x0100;
- amijoy_dev[i].private = amijoy_used + i;
-
input_register_device(amijoy_dev + i);
printk(KERN_INFO "input: %s at joy%ddat\n", amijoy_name, i);
}