[PATCH] i2c: Push ioctl BKL down into the i2c code

[Alan Cox <alan@lxorguk.ukuu.org.uk>]

Signed-off-by: Alan Cox <alan@redhat.com>

diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index d34c14c..16cf0f2 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -34,7 +34,8 @@
 #include <linux/list.h>
 #include <linux/i2c.h>
 #include <linux/i2c-dev.h>
-#include <asm/uaccess.h>
+#include <linux/smp_lock.h>
+#include <linux/uaccess.h>
 
 static struct i2c_driver i2cdev_driver;
 
@@ -266,8 +267,9 @@ static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client,
 		kfree(rdwr_pa);
 		return res;
 	}
-
+	lock_kernel();
 	res = i2c_transfer(client->adapter, rdwr_pa, rdwr_arg.nmsgs);
+	unlock_kernel();
 	while (i-- > 0) {
 		if (res >= 0 && (rdwr_pa[i].flags & I2C_M_RD)) {
 			if (copy_to_user(data_ptrs[i], rdwr_pa[i].buf,
@@ -320,11 +322,15 @@ static noinline int i2cdev_ioctl_smbus(struct i2c_client *client,
 
 	if ((data_arg.size == I2C_SMBUS_QUICK) ||
 	    ((data_arg.size == I2C_SMBUS_BYTE) &&
-	    (data_arg.read_write == I2C_SMBUS_WRITE)))
+	    (data_arg.read_write == I2C_SMBUS_WRITE))) {
 		/* These are special: we do not use data */
-		return i2c_smbus_xfer(client->adapter, client->addr,
+		lock_kernel();
+		res =i2c_smbus_xfer(client->adapter, client->addr,
 				      client->flags, data_arg.read_write,
 				      data_arg.command, data_arg.size, NULL);
+		unlock_kernel();
+		return res;
+	}
 
 	if (data_arg.data == NULL) {
 		dev_dbg(&client->adapter->dev,
@@ -355,8 +361,10 @@ static noinline int i2cdev_ioctl_smbus(struct i2c_client *client,
 		if (data_arg.read_write == I2C_SMBUS_READ)
 			temp.block[0] = I2C_SMBUS_BLOCK_MAX;
 	}
+	lock_kernel();
 	res = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
 	      data_arg.read_write, data_arg.command, data_arg.size, &temp);
+	unlock_kernel();
 	if (!res && ((data_arg.size == I2C_SMBUS_PROC_CALL) ||
 		     (data_arg.size == I2C_SMBUS_BLOCK_PROC_CALL) ||
 		     (data_arg.read_write == I2C_SMBUS_READ))) {
@@ -366,11 +374,12 @@ static noinline int i2cdev_ioctl_smbus(struct i2c_client *client,
 	return res;
 }
 
-static int i2cdev_ioctl(struct inode *inode, struct file *file,
-		unsigned int cmd, unsigned long arg)
+static long i2cdev_ioctl(struct file *file, unsigned int cmd,
+						unsigned long arg)
 {
 	struct i2c_client *client = (struct i2c_client *)file->private_data;
 	unsigned long funcs;
+	int ret = 0;
 
 	dev_dbg(&client->adapter->dev, "ioctl, cmd=0x%02x, arg=0x%02lx\n",
 		cmd, arg);
@@ -388,28 +397,37 @@ static int i2cdev_ioctl(struct inode *inode, struct file *file,
 		 * the PEC flag already set, the i2c-dev driver won't see
 		 * (or use) this setting.
 		 */
+		lock_kernel();
 		if ((arg > 0x3ff) ||
 		    (((client->flags & I2C_M_TEN) == 0) && arg > 0x7f))
-			return -EINVAL;
-		if (cmd == I2C_SLAVE && i2cdev_check_addr(client->adapter, arg))
-			return -EBUSY;
-		/* REVISIT: address could become busy later */
-		client->addr = arg;
-		return 0;
+			ret = -EINVAL;
+		else if (cmd == I2C_SLAVE &&
+				i2cdev_check_addr(client->adapter, arg))
+			ret = -EBUSY;
+		else
+			/* REVISIT: address could become busy later */
+			client->addr = arg;
+		return ret;
 	case I2C_TENBIT:
+		lock_kernel();
 		if (arg)
 			client->flags |= I2C_M_TEN;
 		else
 			client->flags &= ~I2C_M_TEN;
+		unlock_kernel();
 		return 0;
 	case I2C_PEC:
+		lock_kernel();
 		if (arg)
 			client->flags |= I2C_CLIENT_PEC;
 		else
 			client->flags &= ~I2C_CLIENT_PEC;
+		unlock_kernel();
 		return 0;
 	case I2C_FUNCS:
+		lock_kernel();
 		funcs = i2c_get_functionality(client->adapter);
+		unlock_kernel();
 		return put_user(funcs, (unsigned long __user *)arg);
 
 	case I2C_RDWR:
@@ -419,10 +437,14 @@ static int i2cdev_ioctl(struct inode *inode, struct file *file,
 		return i2cdev_ioctl_smbus(client, arg);
 
 	case I2C_RETRIES:
+		lock_kernel();
 		client->adapter->retries = arg;
+		unlock_kernel();
 		break;
 	case I2C_TIMEOUT:
+		lock_kernel();
 		client->adapter->timeout = arg;
+		unlock_kernel();
 		break;
 	default:
 		/* NOTE:  returning a fault code here could cause trouble
@@ -487,7 +509,7 @@ static const struct file_operations i2cdev_fops = {
 	.llseek		= no_llseek,
 	.read		= i2cdev_read,
 	.write		= i2cdev_write,
-	.ioctl		= i2cdev_ioctl,
+	.unlocked_ioctl	= i2cdev_ioctl,
 	.open		= i2cdev_open,
 	.release	= i2cdev_release,
 };