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>

4 files changed, 61 insertions, 23 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);
 		}
diff --git a/drivers/input/joystick/db9.c b/drivers/input/joystick/db9.c
index cfdd3acf06a1..fbd3eed07f90 100644
--- a/drivers/input/joystick/db9.c
+++ b/drivers/input/joystick/db9.c
@@ -87,7 +87,7 @@ __obsolete_setup("db9_3=");
 #define DB9_NORMAL		0x0a
 #define DB9_NOSELECT		0x08
 
-#define DB9_MAX_DEVICES 2
+#define DB9_MAX_DEVICES		2
 
 #define DB9_GENESIS6_DELAY	14
 #define DB9_REFRESH_TIME	HZ/100
@@ -98,6 +98,7 @@ struct db9 {
 	struct pardevice *pd;
 	int mode;
 	int used;
+	struct semaphore sem;
 	char phys[2][32];
 };
 
@@ -503,6 +504,11 @@ static int db9_open(struct input_dev *dev)
 {
 	struct db9 *db9 = dev->private;
 	struct parport *port = db9->pd->port;
+	int err;
+
+	err = down_interruptible(&db9->sem);
+	if (err)
+		return err;
 
 	if (!db9->used++) {
 		parport_claim(db9->pd);
@@ -514,6 +520,7 @@ static int db9_open(struct input_dev *dev)
 		mod_timer(&db9->timer, jiffies + DB9_REFRESH_TIME);
 	}
 
+	up(&db9->sem);
 	return 0;
 }
 
@@ -522,12 +529,14 @@ static void db9_close(struct input_dev *dev)
 	struct db9 *db9 = dev->private;
 	struct parport *port = db9->pd->port;
 
+	down(&db9->sem);
 	if (!--db9->used) {
-		del_timer(&db9->timer);
+		del_timer_sync(&db9->timer);
 		parport_write_control(port, 0x00);
 		parport_data_forward(port);
 		parport_release(db9->pd);
 	}
+	up(&db9->sem);
 }
 
 static struct db9 __init *db9_probe(int *config, int nargs)
@@ -563,12 +572,12 @@ static struct db9 __init *db9_probe(int *config, int nargs)
 		}
 	}
 
-	if (!(db9 = kmalloc(sizeof(struct db9), GFP_KERNEL))) {
+	if (!(db9 = kcalloc(1, sizeof(struct db9), GFP_KERNEL))) {
 		parport_put_port(pp);
 		return NULL;
 	}
-	memset(db9, 0, sizeof(struct db9));
 
+	init_MUTEX(&db9->sem);
 	db9->mode = config[1];
 	init_timer(&db9->timer);
 	db9->timer.data = (long) db9;
diff --git a/drivers/input/joystick/gamecon.c b/drivers/input/joystick/gamecon.c
index 462fc38f026e..95bbdd302aad 100644
--- a/drivers/input/joystick/gamecon.c
+++ b/drivers/input/joystick/gamecon.c
@@ -81,6 +81,7 @@ struct gc {
 	struct timer_list timer;
 	unsigned char pads[GC_MAX + 1];
 	int used;
+	struct semaphore sem;
 	char phys[5][32];
 };
 
@@ -503,22 +504,33 @@ static void gc_timer(unsigned long private)
 static int gc_open(struct input_dev *dev)
 {
 	struct gc *gc = dev->private;
+	int err;
+
+	err = down_interruptible(&gc->sem);
+	if (err)
+		return err;
+
 	if (!gc->used++) {
 		parport_claim(gc->pd);
 		parport_write_control(gc->pd->port, 0x04);
 		mod_timer(&gc->timer, jiffies + GC_REFRESH_TIME);
 	}
+
+	up(&gc->sem);
 	return 0;
 }
 
 static void gc_close(struct input_dev *dev)
 {
 	struct gc *gc = dev->private;
+
+	down(&gc->sem);
 	if (!--gc->used) {
-		del_timer(&gc->timer);
+		del_timer_sync(&gc->timer);
 		parport_write_control(gc->pd->port, 0x00);
 		parport_release(gc->pd);
 	}
+	up(&gc->sem);
 }
 
 static struct gc __init *gc_probe(int *config, int nargs)
@@ -542,11 +554,12 @@ static struct gc __init *gc_probe(int *config, int nargs)
 		return NULL;
 	}
 
-	if (!(gc = kmalloc(sizeof(struct gc), GFP_KERNEL))) {
+	if (!(gc = kcalloc(1, sizeof(struct gc), GFP_KERNEL))) {
 		parport_put_port(pp);
 		return NULL;
 	}
-	memset(gc, 0, sizeof(struct gc));
+
+	init_MUTEX(&gc->sem);
 
 	gc->pd = parport_register_device(pp, "gamecon", NULL, NULL, NULL, PARPORT_DEV_EXCL, NULL);
 
diff --git a/drivers/input/joystick/turbografx.c b/drivers/input/joystick/turbografx.c
index 316c4bebfed2..28100d461cb7 100644
--- a/drivers/input/joystick/turbografx.c
+++ b/drivers/input/joystick/turbografx.c
@@ -84,6 +84,7 @@ static struct tgfx {
 	char phys[7][32];
 	int sticks;
 	int used;
+	struct semaphore sem;
 } *tgfx_base[3];
 
 /*
@@ -123,22 +124,33 @@ static void tgfx_timer(unsigned long private)
 static int tgfx_open(struct input_dev *dev)
 {
 	struct tgfx *tgfx = dev->private;
+	int err;
+
+	err = down_interruptible(&tgfx->sem);
+	if (err)
+		return err;
+
 	if (!tgfx->used++) {
 		parport_claim(tgfx->pd);
 		parport_write_control(tgfx->pd->port, 0x04);
 		mod_timer(&tgfx->timer, jiffies + TGFX_REFRESH_TIME);
 	}
+
+	up(&tgfx->sem);
 	return 0;
 }
 
 static void tgfx_close(struct input_dev *dev)
 {
 	struct tgfx *tgfx = dev->private;
+
+	down(&tgfx->sem);
 	if (!--tgfx->used) {
-		del_timer(&tgfx->timer);
+		del_timer_sync(&tgfx->timer);
 		parport_write_control(tgfx->pd->port, 0x00);
 		parport_release(tgfx->pd);
 	}
+	up(&tgfx->sem);
 }
 
 /*
@@ -166,11 +178,12 @@ static struct tgfx __init *tgfx_probe(int *config, int nargs)
 		return NULL;
 	}
 
-	if (!(tgfx = kmalloc(sizeof(struct tgfx), GFP_KERNEL))) {
+	if (!(tgfx = kcalloc(1, sizeof(struct tgfx), GFP_KERNEL))) {
 		parport_put_port(pp);
 		return NULL;
 	}
-	memset(tgfx, 0, sizeof(struct tgfx));
+
+	init_MUTEX(&tgfx->sem);
 
 	tgfx->pd = parport_register_device(pp, "turbografx", NULL, NULL, NULL, PARPORT_DEV_EXCL, NULL);