fat: split fat_generic_ioctl

Split up fat_generic_ioctl and add separate functions for the two
implemented ioctls.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>

fs/fat/file.c

@@ -18,15 +18,8 @@
 #include <linux/security.h>
 #include "fat.h"
 
-int fat_generic_ioctl(struct inode *inode, struct file *filp,
-		      unsigned int cmd, unsigned long arg)
+static int fat_ioctl_get_attributes(struct inode *inode, u32 __user *user_attr)
 {
-	struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
-	u32 __user *user_attr = (u32 __user *)arg;
-
-	switch (cmd) {
-	case FAT_IOCTL_GET_ATTRIBUTES:
-	{
 	u32 attr;
 
 	mutex_lock(&inode->i_mutex);
@@ -34,22 +27,25 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp,
 	mutex_unlock(&inode->i_mutex);
 
 	return put_user(attr, user_attr);
-	}
-	case FAT_IOCTL_SET_ATTRIBUTES:
-	{
+}
+
+static int fat_ioctl_set_attributes(struct file *file, u32 __user *user_attr)
+{
+	struct inode *inode = file->f_path.dentry->d_inode;
+	struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
+	int is_dir = S_ISDIR(inode->i_mode);
 	u32 attr, oldattr;
-		int err, is_dir = S_ISDIR(inode->i_mode);
 	struct iattr ia;
+	int err;
 
 	err = get_user(attr, user_attr);
 	if (err)
-			return err;
+		goto out;
 
 	mutex_lock(&inode->i_mutex);
-
-		err = mnt_want_write(filp->f_path.mnt);
+	err = mnt_want_write(file->f_path.mnt);
 	if (err)
-			goto up_no_drop_write;
+		goto out_unlock_inode;
 
 	/*
 	 * ATTR_VOLUME and ATTR_DIR cannot be changed; this also
@@ -76,16 +72,14 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp,
 	/* The root directory has no attributes */
 	if (inode->i_ino == MSDOS_ROOT_INO && attr != ATTR_DIR) {
 		err = -EINVAL;
-			goto up;
+		goto out_drop_write;
 	}
 
-		if (sbi->options.sys_immutable) {
-			if ((attr | oldattr) & ATTR_SYS) {
-				if (!capable(CAP_LINUX_IMMUTABLE)) {
+	if (sbi->options.sys_immutable &&
+	    ((attr | oldattr) & ATTR_SYS) &&
+	    !capable(CAP_LINUX_IMMUTABLE)) {
 		err = -EPERM;
-					goto up;
-				}
-			}
+		goto out_drop_write;
 	}
 
 	/*
@@ -93,16 +87,16 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp,
 	 * out the RO attribute for checking by the security
 	 * module, just because it maps to a file mode.
 	 */
-		err = security_inode_setattr(filp->f_path.dentry, &ia);
+	err = security_inode_setattr(file->f_path.dentry, &ia);
 	if (err)
-			goto up;
+		goto out_drop_write;
 
 	/* This MUST be done before doing anything irreversible... */
-		err = fat_setattr(filp->f_path.dentry, &ia);
+	err = fat_setattr(file->f_path.dentry, &ia);
 	if (err)
-			goto up;
+		goto out_drop_write;
 
-		fsnotify_change(filp->f_path.dentry, ia.ia_valid);
+	fsnotify_change(file->f_path.dentry, ia.ia_valid);
 	if (sbi->options.sys_immutable) {
 		if (attr & ATTR_SYS)
 			inode->i_flags |= S_IMMUTABLE;
@@ -112,12 +106,24 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp,
 
 	fat_save_attrs(inode, attr);
 	mark_inode_dirty(inode);
-up:
-		mnt_drop_write(filp->f_path.mnt);
-up_no_drop_write:
+out_drop_write:
+	mnt_drop_write(file->f_path.mnt);
+out_unlock_inode:
 	mutex_unlock(&inode->i_mutex);
+out:
 	return err;
-	}
+}
+
+int fat_generic_ioctl(struct inode *inode, struct file *filp,
+		      unsigned int cmd, unsigned long arg)
+{
+	u32 __user *user_attr = (u32 __user *)arg;
+
+	switch (cmd) {
+	case FAT_IOCTL_GET_ATTRIBUTES:
+		return fat_ioctl_get_attributes(inode, user_attr);
+	case FAT_IOCTL_SET_ATTRIBUTES:
+		return fat_ioctl_set_attributes(filp, user_attr);
 	default:
 		return -ENOTTY;	/* Inappropriate ioctl for device */
 	}