f2fs: revive F2FS_IOC_ABORT_VOLATILE_WRITE

F2FS_IOC_ABORT_VOLATILE_WRITE was used to abort a atomic write before.
However it was removed accidentally. So revive it by changing the name,
since volatile write had gone.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Fiexes: 7bc155fe("f2fs: kill volatile write support")
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/file.c

@@ -2109,6 +2109,31 @@ static int f2fs_ioc_commit_atomic_write(struct file *filp)
 	return ret;
 }
 
+static int f2fs_ioc_abort_atomic_write(struct file *filp)
+{
+	struct inode *inode = file_inode(filp);
+	struct user_namespace *mnt_userns = file_mnt_user_ns(filp);
+	int ret;
+
+	if (!inode_owner_or_capable(mnt_userns, inode))
+		return -EACCES;
+
+	ret = mnt_want_write_file(filp);
+	if (ret)
+		return ret;
+
+	inode_lock(inode);
+
+	if (f2fs_is_atomic_file(inode))
+		f2fs_abort_atomic_write(inode, true);
+
+	inode_unlock(inode);
+
+	mnt_drop_write_file(filp);
+	f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
+	return ret;
+}
+
 static int f2fs_ioc_shutdown(struct file *filp, unsigned long arg)
 {
 	struct inode *inode = file_inode(filp);
@@ -4054,9 +4079,10 @@ static long __f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		return f2fs_ioc_start_atomic_write(filp);
 	case F2FS_IOC_COMMIT_ATOMIC_WRITE:
 		return f2fs_ioc_commit_atomic_write(filp);
+	case F2FS_IOC_ABORT_ATOMIC_WRITE:
+		return f2fs_ioc_abort_atomic_write(filp);
 	case F2FS_IOC_START_VOLATILE_WRITE:
 	case F2FS_IOC_RELEASE_VOLATILE_WRITE:
-	case F2FS_IOC_ABORT_VOLATILE_WRITE:
 		return -EOPNOTSUPP;
 	case F2FS_IOC_SHUTDOWN:
 		return f2fs_ioc_shutdown(filp, arg);
@@ -4725,7 +4751,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	case F2FS_IOC_COMMIT_ATOMIC_WRITE:
 	case F2FS_IOC_START_VOLATILE_WRITE:
 	case F2FS_IOC_RELEASE_VOLATILE_WRITE:
-	case F2FS_IOC_ABORT_VOLATILE_WRITE:
+	case F2FS_IOC_ABORT_ATOMIC_WRITE:
 	case F2FS_IOC_SHUTDOWN:
 	case FITRIM:
 	case FS_IOC_SET_ENCRYPTION_POLICY:

include/uapi/linux/f2fs.h

@@ -13,7 +13,7 @@
 #define F2FS_IOC_COMMIT_ATOMIC_WRITE	_IO(F2FS_IOCTL_MAGIC, 2)
 #define F2FS_IOC_START_VOLATILE_WRITE	_IO(F2FS_IOCTL_MAGIC, 3)
 #define F2FS_IOC_RELEASE_VOLATILE_WRITE	_IO(F2FS_IOCTL_MAGIC, 4)
-#define F2FS_IOC_ABORT_VOLATILE_WRITE	_IO(F2FS_IOCTL_MAGIC, 5)
+#define F2FS_IOC_ABORT_ATOMIC_WRITE	_IO(F2FS_IOCTL_MAGIC, 5)
 #define F2FS_IOC_GARBAGE_COLLECT	_IOW(F2FS_IOCTL_MAGIC, 6, __u32)
 #define F2FS_IOC_WRITE_CHECKPOINT	_IO(F2FS_IOCTL_MAGIC, 7)
 #define F2FS_IOC_DEFRAGMENT		_IOWR(F2FS_IOCTL_MAGIC, 8,	\