@@ -20,7 +20,6 @@
 #include <asm/unaligned.h>
 #include <linux/pagemap.h>
 #include <linux/btrfs.h>
-#include <linux/btrfs_tree.h>
 #include <linux/workqueue.h>
 #include <linux/security.h>
 #include <linux/sizes.h>

@@ -28,6 +27,7 @@
 #include <linux/refcount.h>
 #include <linux/crc32c.h>
 #include <linux/iomap.h>
+#include "ondisk_format.h"
 #include "extent-io-tree.h"
 #include "extent_io.h"
 #include "extent_map.h"

@@ -50,8 +50,6 @@ struct btrfs_ordered_sum;
 struct btrfs_ref;
 struct btrfs_bio;
 
-#define BTRFS_MAGIC 0x4D5F53665248425FULL /* ascii _BHRfS_M, no null */
-
 /*
  * Maximum number of mirrors that can be available for all profiles counting
  * the target device of dev-replace as one. During an active device replace

@@ -145,212 +143,6 @@ enum {
 	BTRFS_FS_STATE_DUMMY_FS_INFO,
 };
 
-#define BTRFS_BACKREF_REV_MAX		256
-#define BTRFS_BACKREF_REV_SHIFT		56
-#define BTRFS_BACKREF_REV_MASK		(((u64)BTRFS_BACKREF_REV_MAX - 1) << \
-					 BTRFS_BACKREF_REV_SHIFT)
-
-#define BTRFS_OLD_BACKREF_REV		0
-#define BTRFS_MIXED_BACKREF_REV		1
-
-/*
- * every tree block (leaf or node) starts with this header.
- */
-struct btrfs_header {
-	/* these first four must match the super block */
-	u8 csum[BTRFS_CSUM_SIZE];
-	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
-	__le64 bytenr; /* which block this node is supposed to live in */
-	__le64 flags;
-
-	/* allowed to be different from the super from here on down */
-	u8 chunk_tree_uuid[BTRFS_UUID_SIZE];
-	__le64 generation;
-	__le64 owner;
-	__le32 nritems;
-	u8 level;
-} __attribute__ ((__packed__));
-
-/*
- * this is a very generous portion of the super block, giving us
- * room to translate 14 chunks with 3 stripes each.
- */
-#define BTRFS_SYSTEM_CHUNK_ARRAY_SIZE 2048
-
-/*
- * just in case we somehow lose the roots and are not able to mount,
- * we store an array of the roots from previous transactions
- * in the super.
- */
-#define BTRFS_NUM_BACKUP_ROOTS 4
-struct btrfs_root_backup {
-	__le64 tree_root;
-	__le64 tree_root_gen;
-
-	__le64 chunk_root;
-	__le64 chunk_root_gen;
-
-	__le64 extent_root;
-	__le64 extent_root_gen;
-
-	__le64 fs_root;
-	__le64 fs_root_gen;
-
-	__le64 dev_root;
-	__le64 dev_root_gen;
-
-	__le64 csum_root;
-	__le64 csum_root_gen;
-
-	__le64 total_bytes;
-	__le64 bytes_used;
-	__le64 num_devices;
-	/* future */
-	__le64 unused_64[4];
-
-	u8 tree_root_level;
-	u8 chunk_root_level;
-	u8 extent_root_level;
-	u8 fs_root_level;
-	u8 dev_root_level;
-	u8 csum_root_level;
-	/* future and to align */
-	u8 unused_8[10];
-} __attribute__ ((__packed__));
-
-#define BTRFS_SUPER_INFO_OFFSET			SZ_64K
-#define BTRFS_SUPER_INFO_SIZE			4096
-
-/*
- * the super block basically lists the main trees of the FS
- * it currently lacks any block count etc etc
- */
-struct btrfs_super_block {
-	/* the first 4 fields must match struct btrfs_header */
-	u8 csum[BTRFS_CSUM_SIZE];
-	/* FS specific UUID, visible to user */
-	u8 fsid[BTRFS_FSID_SIZE];
-	__le64 bytenr; /* this block number */
-	__le64 flags;
-
-	/* allowed to be different from the btrfs_header from here own down */
-	__le64 magic;
-	__le64 generation;
-	__le64 root;
-	__le64 chunk_root;
-	__le64 log_root;
-
-	/* this will help find the new super based on the log root */
-	__le64 log_root_transid;
-	__le64 total_bytes;
-	__le64 bytes_used;
-	__le64 root_dir_objectid;
-	__le64 num_devices;
-	__le32 sectorsize;
-	__le32 nodesize;
-	__le32 __unused_leafsize;
-	__le32 stripesize;
-	__le32 sys_chunk_array_size;
-	__le64 chunk_root_generation;
-	__le64 compat_flags;
-	__le64 compat_ro_flags;
-	__le64 incompat_flags;
-	__le16 csum_type;
-	u8 root_level;
-	u8 chunk_root_level;
-	u8 log_root_level;
-	struct btrfs_dev_item dev_item;
-
-	char label[BTRFS_LABEL_SIZE];
-
-	__le64 cache_generation;
-	__le64 uuid_tree_generation;
-
-	/* the UUID written into btree blocks */
-	u8 metadata_uuid[BTRFS_FSID_SIZE];
-
-	/* future expansion */
-	__le64 reserved[28];
-	u8 sys_chunk_array[BTRFS_SYSTEM_CHUNK_ARRAY_SIZE];
-	struct btrfs_root_backup super_roots[BTRFS_NUM_BACKUP_ROOTS];
-
-	/* Padded to 4096 bytes */
-	u8 padding[565];
-} __attribute__ ((__packed__));
-static_assert(sizeof(struct btrfs_super_block) == BTRFS_SUPER_INFO_SIZE);
-
-/*
- * Compat flags that we support.  If any incompat flags are set other than the
- * ones specified below then we will fail to mount
- */
-#define BTRFS_FEATURE_COMPAT_SUPP		0ULL
-#define BTRFS_FEATURE_COMPAT_SAFE_SET		0ULL
-#define BTRFS_FEATURE_COMPAT_SAFE_CLEAR		0ULL
-
-#define BTRFS_FEATURE_COMPAT_RO_SUPP			\
-	(BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE |	\
-	 BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID | \
-	 BTRFS_FEATURE_COMPAT_RO_VERITY)
-
-#define BTRFS_FEATURE_COMPAT_RO_SAFE_SET	0ULL
-#define BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR	0ULL
-
-#define BTRFS_FEATURE_INCOMPAT_SUPP			\
-	(BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF |		\
-	 BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL |	\
-	 BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS |		\
-	 BTRFS_FEATURE_INCOMPAT_BIG_METADATA |		\
-	 BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO |		\
-	 BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD |		\
-	 BTRFS_FEATURE_INCOMPAT_RAID56 |		\
-	 BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF |		\
-	 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA |	\
-	 BTRFS_FEATURE_INCOMPAT_NO_HOLES	|	\
-	 BTRFS_FEATURE_INCOMPAT_METADATA_UUID	|	\
-	 BTRFS_FEATURE_INCOMPAT_RAID1C34	|	\
-	 BTRFS_FEATURE_INCOMPAT_ZONED)
-
-#define BTRFS_FEATURE_INCOMPAT_SAFE_SET			\
-	(BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF)
-#define BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR		0ULL
-
-/*
- * A leaf is full of items. offset and size tell us where to find
- * the item in the leaf (relative to the start of the data area)
- */
-struct btrfs_item {
-	struct btrfs_disk_key key;
-	__le32 offset;
-	__le32 size;
-} __attribute__ ((__packed__));
-
-/*
- * leaves have an item area and a data area:
- * [item0, item1....itemN] [free space] [dataN...data1, data0]
- *
- * The data is separate from the items to get the keys closer together
- * during searches.
- */
-struct btrfs_leaf {
-	struct btrfs_header header;
-	struct btrfs_item items[];
-} __attribute__ ((__packed__));
-
-/*
- * all non-leaf blocks are nodes, they hold only keys and pointers to
- * other blocks
- */
-struct btrfs_key_ptr {
-	struct btrfs_disk_key key;
-	__le64 blockptr;
-	__le64 generation;
-} __attribute__ ((__packed__));
-
-struct btrfs_node {
-	struct btrfs_header header;
-	struct btrfs_key_ptr ptrs[];
-} __attribute__ ((__packed__));
-
 /* Read ahead values for struct btrfs_path.reada */
 enum {
 	READA_NONE,

@@ -0,0 +1,223 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef BTRFS_ONDISK_FORMAT_H
+#define BTRFS_ONDISK_FORMAT_H
+
+#include <linux/types.h>
+/*
+ * Most btrfs on-disk format is exposed through btrfs_tree.h uapi header
+ * already, as SEARCH_TREE ioctl can expose the tree directly to user space.
+ */
+#include <linux/btrfs_tree.h>
+
+/* Only structures not exposed through tree search ioctl are kept here. */
+
+#define BTRFS_MAGIC 0x4D5F53665248425FULL /* ascii _BHRfS_M, no null */
+
+#define BTRFS_BACKREF_REV_MAX		256
+#define BTRFS_BACKREF_REV_SHIFT		56
+#define BTRFS_BACKREF_REV_MASK		(((u64)BTRFS_BACKREF_REV_MAX - 1) << \
+					 BTRFS_BACKREF_REV_SHIFT)
+
+#define BTRFS_OLD_BACKREF_REV		0
+#define BTRFS_MIXED_BACKREF_REV		1
+
+/*
+ * every tree block (leaf or node) starts with this header.
+ */
+struct btrfs_header {
+	/* these first four must match the super block */
+	u8 csum[BTRFS_CSUM_SIZE];
+	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
+	__le64 bytenr; /* which block this node is supposed to live in */
+	__le64 flags;
+
+	/* allowed to be different from the super from here on down */
+	u8 chunk_tree_uuid[BTRFS_UUID_SIZE];
+	__le64 generation;
+	__le64 owner;
+	__le32 nritems;
+	u8 level;
+} __attribute__ ((__packed__));
+
+/*
+ * this is a very generous portion of the super block, giving us
+ * room to translate 14 chunks with 3 stripes each.
+ */
+#define BTRFS_SYSTEM_CHUNK_ARRAY_SIZE 2048
+
+/*
+ * just in case we somehow lose the roots and are not able to mount,
+ * we store an array of the roots from previous transactions
+ * in the super.
+ */
+#define BTRFS_NUM_BACKUP_ROOTS 4
+struct btrfs_root_backup {
+	__le64 tree_root;
+	__le64 tree_root_gen;
+
+	__le64 chunk_root;
+	__le64 chunk_root_gen;
+
+	__le64 extent_root;
+	__le64 extent_root_gen;
+
+	__le64 fs_root;
+	__le64 fs_root_gen;
+
+	__le64 dev_root;
+	__le64 dev_root_gen;
+
+	__le64 csum_root;
+	__le64 csum_root_gen;
+
+	__le64 total_bytes;
+	__le64 bytes_used;
+	__le64 num_devices;
+	/* future */
+	__le64 unused_64[4];
+
+	u8 tree_root_level;
+	u8 chunk_root_level;
+	u8 extent_root_level;
+	u8 fs_root_level;
+	u8 dev_root_level;
+	u8 csum_root_level;
+	/* future and to align */
+	u8 unused_8[10];
+} __attribute__ ((__packed__));
+
+#define BTRFS_SUPER_INFO_OFFSET			SZ_64K
+#define BTRFS_SUPER_INFO_SIZE			4096
+
+/*
+ * the super block basically lists the main trees of the FS
+ * it currently lacks any block count etc etc
+ */
+struct btrfs_super_block {
+	/* the first 4 fields must match struct btrfs_header */
+	u8 csum[BTRFS_CSUM_SIZE];
+	/* FS specific UUID, visible to user */
+	u8 fsid[BTRFS_FSID_SIZE];
+	__le64 bytenr; /* this block number */
+	__le64 flags;
+
+	/* allowed to be different from the btrfs_header from here own down */
+	__le64 magic;
+	__le64 generation;
+	__le64 root;
+	__le64 chunk_root;
+	__le64 log_root;
+
+	/* this will help find the new super based on the log root */
+	__le64 log_root_transid;
+	__le64 total_bytes;
+	__le64 bytes_used;
+	__le64 root_dir_objectid;
+	__le64 num_devices;
+	__le32 sectorsize;
+	__le32 nodesize;
+	__le32 __unused_leafsize;
+	__le32 stripesize;
+	__le32 sys_chunk_array_size;
+	__le64 chunk_root_generation;
+	__le64 compat_flags;
+	__le64 compat_ro_flags;
+	__le64 incompat_flags;
+	__le16 csum_type;
+	u8 root_level;
+	u8 chunk_root_level;
+	u8 log_root_level;
+	struct btrfs_dev_item dev_item;
+
+	char label[BTRFS_LABEL_SIZE];
+
+	__le64 cache_generation;
+	__le64 uuid_tree_generation;
+
+	/* the UUID written into btree blocks */
+	u8 metadata_uuid[BTRFS_FSID_SIZE];
+
+	/* future expansion */
+	__le64 reserved[28];
+	u8 sys_chunk_array[BTRFS_SYSTEM_CHUNK_ARRAY_SIZE];
+	struct btrfs_root_backup super_roots[BTRFS_NUM_BACKUP_ROOTS];
+
+	/* Padded to 4096 bytes */
+	u8 padding[565];
+} __attribute__ ((__packed__));
+static_assert(sizeof(struct btrfs_super_block) == BTRFS_SUPER_INFO_SIZE);
+
+/*
+ * Compat flags that we support.  If any incompat flags are set other than the
+ * ones specified below then we will fail to mount
+ */
+#define BTRFS_FEATURE_COMPAT_SUPP		0ULL
+#define BTRFS_FEATURE_COMPAT_SAFE_SET		0ULL
+#define BTRFS_FEATURE_COMPAT_SAFE_CLEAR		0ULL
+
+#define BTRFS_FEATURE_COMPAT_RO_SUPP			\
+	(BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE |	\
+	 BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID | \
+	 BTRFS_FEATURE_COMPAT_RO_VERITY)
+
+#define BTRFS_FEATURE_COMPAT_RO_SAFE_SET	0ULL
+#define BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR	0ULL
+
+#define BTRFS_FEATURE_INCOMPAT_SUPP			\
+	(BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF |		\
+	 BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL |	\
+	 BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS |		\
+	 BTRFS_FEATURE_INCOMPAT_BIG_METADATA |		\
+	 BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO |		\
+	 BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD |		\
+	 BTRFS_FEATURE_INCOMPAT_RAID56 |		\
+	 BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF |		\
+	 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA |	\
+	 BTRFS_FEATURE_INCOMPAT_NO_HOLES	|	\
+	 BTRFS_FEATURE_INCOMPAT_METADATA_UUID	|	\
+	 BTRFS_FEATURE_INCOMPAT_RAID1C34	|	\
+	 BTRFS_FEATURE_INCOMPAT_ZONED)
+
+#define BTRFS_FEATURE_INCOMPAT_SAFE_SET			\
+	(BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF)
+#define BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR		0ULL
+
+/*
+ * A leaf is full of items. offset and size tell us where to find
+ * the item in the leaf (relative to the start of the data area)
+ */
+struct btrfs_item {
+	struct btrfs_disk_key key;
+	__le32 offset;
+	__le32 size;
+} __attribute__ ((__packed__));
+
+/*
+ * leaves have an item area and a data area:
+ * [item0, item1....itemN] [free space] [dataN...data1, data0]
+ *
+ * The data is separate from the items to get the keys closer together
+ * during searches.
+ */
+struct btrfs_leaf {
+	struct btrfs_header header;
+	struct btrfs_item items[];
+} __attribute__ ((__packed__));
+
+/*
+ * all non-leaf blocks are nodes, they hold only keys and pointers to
+ * other blocks
+ */
+struct btrfs_key_ptr {
+	struct btrfs_disk_key key;
+	__le64 blockptr;
+	__le64 generation;
+} __attribute__ ((__packed__));
+
+struct btrfs_node {
+	struct btrfs_header header;
+	struct btrfs_key_ptr ptrs[];
+} __attribute__ ((__packed__));
+
+#endif