diff --git a/include/crucible/btrfs.h b/include/crucible/btrfs.h
index 2792679..568ead4 100644
--- a/include/crucible/btrfs.h
+++ b/include/crucible/btrfs.h
@@ -205,8 +205,27 @@
 #endif
 
 #ifndef BTRFS_IOC_LOGICAL_INO_V2
-#define BTRFS_IOC_LOGICAL_INO_V2 _IOWR(BTRFS_IOCTL_MAGIC, 59, struct btrfs_ioctl_logical_ino_args)
-#define BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET (1ULL << 0)
+	#define BTRFS_IOC_LOGICAL_INO_V2 _IOWR(BTRFS_IOCTL_MAGIC, 59, struct btrfs_ioctl_logical_ino_args)
+	#define BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET (1ULL << 0)
 #endif
 
+#ifndef BTRFS_FS_INFO_FLAG_CSUM_INFO
+	/* Request information about checksum type and size */
+	#define BTRFS_FS_INFO_FLAG_CSUM_INFO                    (1 << 0)
+#endif
+
+struct btrfs_ioctl_fs_info_args_v2 {
+	__u64 max_id;                           /* out */
+	__u64 num_devices;                      /* out */
+	__u8 fsid[BTRFS_FSID_SIZE];             /* out */
+	__u32 nodesize;                         /* out */
+	__u32 sectorsize;                       /* out */
+	__u32 clone_alignment;                  /* out */
+	/* See BTRFS_FS_INFO_FLAG_* */
+	__u16 csum_type;                        /* out */
+	__u16 csum_size;                        /* out */
+	__u64 flags;                            /* in/out */
+	__u8 reserved[968];                     /* pad to 1k */
+};
+
 #endif // CRUCIBLE_BTRFS_H
diff --git a/include/crucible/fs.h b/include/crucible/fs.h
index 05ee5e1..0e7e04d 100644
--- a/include/crucible/fs.h
+++ b/include/crucible/fs.h
@@ -258,10 +258,12 @@ namespace crucible {
 
 	ostream &hexdump(ostream &os, const vector<char> &v);
 
-	struct BtrfsIoctlFsInfoArgs : public btrfs_ioctl_fs_info_args {
+	struct BtrfsIoctlFsInfoArgs : public btrfs_ioctl_fs_info_args_v2 {
 		BtrfsIoctlFsInfoArgs();
 		void do_ioctl(int fd);
 		string uuid() const;
+		uint16_t csum_type() const;
+		uint16_t csum_size() const;
 	};
 
 	ostream & operator<<(ostream &os, const BtrfsIoctlFsInfoArgs &a);
diff --git a/lib/fs.cc b/lib/fs.cc
index e7dd7e7..401d1db 100644
--- a/lib/fs.cc
+++ b/lib/fs.cc
@@ -1084,13 +1084,14 @@ namespace crucible {
 
 	BtrfsIoctlFsInfoArgs::BtrfsIoctlFsInfoArgs()
 	{
-		memset_zero<btrfs_ioctl_fs_info_args>(this);
+		memset_zero<btrfs_ioctl_fs_info_args_v2>(this);
+		flags = BTRFS_FS_INFO_FLAG_CSUM_INFO;
 	}
 
 	void
 	BtrfsIoctlFsInfoArgs::do_ioctl(int fd)
 	{
-		btrfs_ioctl_fs_info_args *p = static_cast<btrfs_ioctl_fs_info_args *>(this);
+		btrfs_ioctl_fs_info_args_v2 *p = static_cast<btrfs_ioctl_fs_info_args_v2 *>(this);
 		if (ioctl(fd, BTRFS_IOC_FS_INFO, p)) {
 			THROW_ERRNO("BTRFS_IOC_FS_INFO: fd " << fd);
 		}
@@ -1102,4 +1103,16 @@ namespace crucible {
 		return uuid_unparse(fsid);
 	}
 
+	uint16_t
+	BtrfsIoctlFsInfoArgs::csum_type() const
+	{
+		return this->btrfs_ioctl_fs_info_args_v2::csum_type;
+	}
+
+	uint16_t
+	BtrfsIoctlFsInfoArgs::csum_size() const
+	{
+		return this->btrfs_ioctl_fs_info_args_v2::csum_size;
+	}
+
 };