[PATCH 0/7] Move some code out of ctree.c and ctree.h

[PATCH 0/7] Move some code out of ctree.c and ctree.h

[David Sterba]

The ctree.[ch] files gathered a lot of unrelated code over the years, it
should be moved to appropriate files. This series does the easiest part,
nes I'll split the incompate/feature handling and messages.

David Sterba (7):
  btrfs: move cond_wake_up functions out of ctree
  btrfs: move math functions to misc.h
  btrfs: move private raid56 definitions from ctree.h
  btrfs: rename and export read_node_slot
  btrfs: move functions for tree compare to send.c
  btrfs: move struct io_ctl to free-space-cache.h
  btrfs: move dev_stats helpers to volumes.c

 fs/btrfs/block-group.c      |   2 +-
 fs/btrfs/block-group.h      |   2 +
 fs/btrfs/block-rsv.c        |   2 +-
 fs/btrfs/compression.c      |   1 +
 fs/btrfs/ctree.c            | 382 +-----------------------------------
 fs/btrfs/ctree.h            |  93 +--------
 fs/btrfs/delayed-inode.c    |   1 +
 fs/btrfs/dev-replace.c      |   1 +
 fs/btrfs/extent-tree.c      |   2 +-
 fs/btrfs/free-space-cache.h |  14 +-
 fs/btrfs/inode.c            |   1 +
 fs/btrfs/locking.c          |   1 +
 fs/btrfs/math.h             |  28 ---
 fs/btrfs/misc.h             |  50 +++++
 fs/btrfs/ordered-data.c     |   1 +
 fs/btrfs/raid56.c           |  16 ++
 fs/btrfs/send.c             | 374 +++++++++++++++++++++++++++++++++++
 fs/btrfs/space-info.c       |   2 +-
 fs/btrfs/transaction.c      |   1 +
 fs/btrfs/tree-log.c         |   1 +
 fs/btrfs/volumes.c          |  25 ++-
 fs/btrfs/zstd.c             |   1 +
 22 files changed, 505 insertions(+), 496 deletions(-)
 delete mode 100644 fs/btrfs/math.h
 create mode 100644 fs/btrfs/misc.h

-- 
2.22.0

[PATCH 1/7] btrfs: move cond_wake_up functions out of ctree

[David Sterba]

The file ctree.h serves as a header for everything and has become quite
bloated. Split some helpers that are generic and create a new file that
should be the catch-all for code that's not btrfs-specific.

Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/compression.c   |  1 +
 fs/btrfs/ctree.h         | 22 ----------------------
 fs/btrfs/delayed-inode.c |  1 +
 fs/btrfs/dev-replace.c   |  1 +
 fs/btrfs/extent-tree.c   |  1 +
 fs/btrfs/inode.c         |  1 +
 fs/btrfs/locking.c       |  1 +
 fs/btrfs/misc.h          | 33 +++++++++++++++++++++++++++++++++
 fs/btrfs/ordered-data.c  |  1 +
 fs/btrfs/transaction.c   |  1 +
 fs/btrfs/tree-log.c      |  1 +
 fs/btrfs/zstd.c          |  1 +
 12 files changed, 43 insertions(+), 22 deletions(-)
 create mode 100644 fs/btrfs/misc.h

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index fe7a8b5ff96c..b05b361e2062 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -18,6 +18,7 @@
 #include <linux/sched/mm.h>
 #include <linux/log2.h>
 #include <crypto/hash.h>
+#include "misc.h"
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index d27b39858339..70d1b9767a96 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3516,26 +3516,4 @@ static inline int btrfs_is_testing(struct btrfs_fs_info *fs_info)
 }
 #endif
 
-static inline void cond_wake_up(struct wait_queue_head *wq)
-{
-	/*
-	 * This implies a full smp_mb barrier, see comments for
-	 * waitqueue_active why.
-	 */
-	if (wq_has_sleeper(wq))
-		wake_up(wq);
-}
-
-static inline void cond_wake_up_nomb(struct wait_queue_head *wq)
-{
-	/*
-	 * Special case for conditional wakeup where the barrier required for
-	 * waitqueue_active is implied by some of the preceding code. Eg. one
-	 * of such atomic operations (atomic_dec_and_return, ...), or a
-	 * unlock/lock sequence, etc.
-	 */
-	if (waitqueue_active(wq))
-		wake_up(wq);
-}
-
 #endif
diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index 9318cf761a07..1f7f39b10bd0 100644
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -6,6 +6,7 @@
 
 #include <linux/slab.h>
 #include <linux/iversion.h>
+#include "misc.h"
 #include "delayed-inode.h"
 #include "disk-io.h"
 #include "transaction.h"
diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 00ea828beb00..48890826b5e6 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -9,6 +9,7 @@
 #include <linux/blkdev.h>
 #include <linux/kthread.h>
 #include <linux/math64.h>
+#include "misc.h"
 #include "ctree.h"
 #include "extent_map.h"
 #include "disk-io.h"
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index af7631472073..795b592e5269 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -16,6 +16,7 @@
 #include <linux/percpu_counter.h>
 #include <linux/lockdep.h>
 #include <linux/crc32c.h>
+#include "misc.h"
 #include "tree-log.h"
 #include "disk-io.h"
 #include "print-tree.h"
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index aece5dd0e7a8..30adbdd775a3 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -30,6 +30,7 @@
 #include <linux/swap.h>
 #include <linux/sched/mm.h>
 #include <asm/unaligned.h>
+#include "misc.h"
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c
index e4309bcf0b5f..7f9a578a1a20 100644
--- a/fs/btrfs/locking.c
+++ b/fs/btrfs/locking.c
@@ -8,6 +8,7 @@
 #include <linux/spinlock.h>
 #include <linux/page-flags.h>
 #include <asm/bug.h>
+#include "misc.h"
 #include "ctree.h"
 #include "extent_io.h"
 #include "locking.h"
diff --git a/fs/btrfs/misc.h b/fs/btrfs/misc.h
new file mode 100644
index 000000000000..ef3901238ddd
--- /dev/null
+++ b/fs/btrfs/misc.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef BTRFS_MISC_H
+#define BTRFS_MISC_H
+
+#include <linux/sched.h>
+#include <linux/wait.h>
+
+#define in_range(b, first, len) ((b) >= (first) && (b) < (first) + (len))
+
+static inline void cond_wake_up(struct wait_queue_head *wq)
+{
+	/*
+	 * This implies a full smp_mb barrier, see comments for
+	 * waitqueue_active why.
+	 */
+	if (wq_has_sleeper(wq))
+		wake_up(wq);
+}
+
+static inline void cond_wake_up_nomb(struct wait_queue_head *wq)
+{
+	/*
+	 * Special case for conditional wakeup where the barrier required for
+	 * waitqueue_active is implied by some of the preceding code. Eg. one
+	 * of such atomic operations (atomic_dec_and_return, ...), or a
+	 * unlock/lock sequence, etc.
+	 */
+	if (waitqueue_active(wq))
+		wake_up(wq);
+}
+
+#endif
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index ae7f64a8facb..24b6c72b9a59 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -7,6 +7,7 @@
 #include <linux/blkdev.h>
 #include <linux/writeback.h>
 #include <linux/sched/mm.h>
+#include "misc.h"
 #include "ctree.h"
 #include "transaction.h"
 #include "btrfs_inode.h"
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index f21416d68c2c..8624bdee8c5b 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -10,6 +10,7 @@
 #include <linux/pagemap.h>
 #include <linux/blkdev.h>
 #include <linux/uuid.h>
+#include "misc.h"
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 19a4b9dc669f..34d087008b72 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -8,6 +8,7 @@
 #include <linux/blkdev.h>
 #include <linux/list_sort.h>
 #include <linux/iversion.h>
+#include "misc.h"
 #include "ctree.h"
 #include "tree-log.h"
 #include "disk-io.h"
diff --git a/fs/btrfs/zstd.c b/fs/btrfs/zstd.c
index 0af4a5cd4313..764d47b107e5 100644
--- a/fs/btrfs/zstd.c
+++ b/fs/btrfs/zstd.c
@@ -17,6 +17,7 @@
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/zstd.h>
+#include "misc.h"
 #include "compression.h"
 #include "ctree.h"
 
-- 
2.22.0

[PATCH 2/7] btrfs: move math functions to misc.h

[David Sterba]

Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/block-group.c |  2 +-
 fs/btrfs/block-rsv.c   |  2 +-
 fs/btrfs/extent-tree.c |  1 -
 fs/btrfs/math.h        | 28 ----------------------------
 fs/btrfs/misc.h        | 17 +++++++++++++++++
 fs/btrfs/space-info.c  |  2 +-
 fs/btrfs/volumes.c     |  2 +-
 7 files changed, 21 insertions(+), 33 deletions(-)
 delete mode 100644 fs/btrfs/math.h

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index 162fd9d13b36..10ba8eddec22 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 
+#include "misc.h"
 #include "ctree.h"
 #include "block-group.h"
 #include "space-info.h"
@@ -13,7 +14,6 @@
 #include "sysfs.h"
 #include "tree-log.h"
 #include "delalloc-space.h"
-#include "math.h"
 
 /*
  * Return target flags in extended format or 0 if restripe for this chunk_type
diff --git a/fs/btrfs/block-rsv.c b/fs/btrfs/block-rsv.c
index 698470b9f32d..ef8b8ae27386 100644
--- a/fs/btrfs/block-rsv.c
+++ b/fs/btrfs/block-rsv.c
@@ -1,9 +1,9 @@
 // SPDX-License-Identifier: GPL-2.0
 
+#include "misc.h"
 #include "ctree.h"
 #include "block-rsv.h"
 #include "space-info.h"
-#include "math.h"
 #include "transaction.h"
 
 static u64 block_rsv_release_bytes(struct btrfs_fs_info *fs_info,
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 795b592e5269..2bf5dad82bf1 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -25,7 +25,6 @@
 #include "locking.h"
 #include "free-space-cache.h"
 #include "free-space-tree.h"
-#include "math.h"
 #include "sysfs.h"
 #include "qgroup.h"
 #include "ref-verify.h"
diff --git a/fs/btrfs/math.h b/fs/btrfs/math.h
deleted file mode 100644
index 75246f2f56ba..000000000000
--- a/fs/btrfs/math.h
+++ /dev/null
@@ -1,28 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Copyright (C) 2012 Fujitsu.  All rights reserved.
- * Written by Miao Xie <miaox@cn.fujitsu.com>
- */
-
-#ifndef BTRFS_MATH_H
-#define BTRFS_MATH_H
-
-#include <asm/div64.h>
-
-static inline u64 div_factor(u64 num, int factor)
-{
-	if (factor == 10)
-		return num;
-	num *= factor;
-	return div_u64(num, 10);
-}
-
-static inline u64 div_factor_fine(u64 num, int factor)
-{
-	if (factor == 100)
-		return num;
-	num *= factor;
-	return div_u64(num, 100);
-}
-
-#endif
diff --git a/fs/btrfs/misc.h b/fs/btrfs/misc.h
index ef3901238ddd..7d564924dfeb 100644
--- a/fs/btrfs/misc.h
+++ b/fs/btrfs/misc.h
@@ -5,6 +5,7 @@
 
 #include <linux/sched.h>
 #include <linux/wait.h>
+#include <asm/div64.h>
 
 #define in_range(b, first, len) ((b) >= (first) && (b) < (first) + (len))
 
@@ -30,4 +31,20 @@ static inline void cond_wake_up_nomb(struct wait_queue_head *wq)
 		wake_up(wq);
 }
 
+static inline u64 div_factor(u64 num, int factor)
+{
+	if (factor == 10)
+		return num;
+	num *= factor;
+	return div_u64(num, 10);
+}
+
+static inline u64 div_factor_fine(u64 num, int factor)
+{
+	if (factor == 100)
+		return num;
+	num *= factor;
+	return div_u64(num, 100);
+}
+
 #endif
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index 13a4326c8821..bea7ae0a9739 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 
+#include "misc.h"
 #include "ctree.h"
 #include "space-info.h"
 #include "sysfs.h"
@@ -7,7 +8,6 @@
 #include "free-space-cache.h"
 #include "ordered-data.h"
 #include "transaction.h"
-#include "math.h"
 #include "block-group.h"
 
 u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index e2de7c7b674a..dc1f6985c2c4 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -14,6 +14,7 @@
 #include <linux/semaphore.h>
 #include <linux/uuid.h>
 #include <linux/list_sort.h>
+#include "misc.h"
 #include "ctree.h"
 #include "extent_map.h"
 #include "disk-io.h"
@@ -24,7 +25,6 @@
 #include "async-thread.h"
 #include "check-integrity.h"
 #include "rcu-string.h"
-#include "math.h"
 #include "dev-replace.h"
 #include "sysfs.h"
 #include "tree-checker.h"
-- 
2.22.0

[PATCH 3/7] btrfs: move private raid56 definitions from ctree.h

[David Sterba]

Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/ctree.h  | 16 ----------------
 fs/btrfs/raid56.c | 16 ++++++++++++++++
 2 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 70d1b9767a96..a7291e7dd574 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -470,22 +470,6 @@ enum btrfs_orphan_cleanup_state {
 	ORPHAN_CLEANUP_DONE	= 2,
 };
 
-/* used by the raid56 code to lock stripes for read/modify/write */
-struct btrfs_stripe_hash {
-	struct list_head hash_list;
-	spinlock_t lock;
-};
-
-/* used by the raid56 code to lock stripes for read/modify/write */
-struct btrfs_stripe_hash_table {
-	struct list_head stripe_cache;
-	spinlock_t cache_lock;
-	int cache_size;
-	struct btrfs_stripe_hash table[];
-};
-
-#define BTRFS_STRIPE_HASH_TABLE_BITS 11
-
 void btrfs_init_async_reclaim_work(struct work_struct *work);
 
 /* fs_info */
diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c
index f3d0576dd327..57a2ac721985 100644
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -35,6 +35,22 @@
 
 #define RBIO_CACHE_SIZE 1024
 
+#define BTRFS_STRIPE_HASH_TABLE_BITS				11
+
+/* Used by the raid56 code to lock stripes for read/modify/write */
+struct btrfs_stripe_hash {
+	struct list_head hash_list;
+	spinlock_t lock;
+};
+
+/* Used by the raid56 code to lock stripes for read/modify/write */
+struct btrfs_stripe_hash_table {
+	struct list_head stripe_cache;
+	spinlock_t cache_lock;
+	int cache_size;
+	struct btrfs_stripe_hash table[];
+};
+
 enum btrfs_rbio_ops {
 	BTRFS_RBIO_WRITE,
 	BTRFS_RBIO_READ_REBUILD,
-- 
2.22.0

[PATCH 4/7] btrfs: rename and export read_node_slot

[David Sterba]

Preparatory work for code that will be moved out of ctree and uses this
function.

Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/ctree.c | 22 +++++++++++-----------
 fs/btrfs/ctree.h |  3 +++
 2 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index a2f3cd7a619c..3b585f3e4d11 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -1792,8 +1792,8 @@ static void root_sub_used(struct btrfs_root *root, u32 size)
 /* given a node and slot number, this reads the blocks it points to.  The
  * extent buffer is returned with a reference taken (but unlocked).
  */
-static noinline struct extent_buffer *read_node_slot(
-				struct extent_buffer *parent, int slot)
+struct extent_buffer *btrfs_read_node_slot(struct extent_buffer *parent,
+					   int slot)
 {
 	int level = btrfs_header_level(parent);
 	struct extent_buffer *eb;
@@ -1862,7 +1862,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 			return 0;
 
 		/* promote the child to a root */
-		child = read_node_slot(mid, 0);
+		child = btrfs_read_node_slot(mid, 0);
 		if (IS_ERR(child)) {
 			ret = PTR_ERR(child);
 			btrfs_handle_fs_error(fs_info, ret, NULL);
@@ -1902,7 +1902,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 	    BTRFS_NODEPTRS_PER_BLOCK(fs_info) / 4)
 		return 0;
 
-	left = read_node_slot(parent, pslot - 1);
+	left = btrfs_read_node_slot(parent, pslot - 1);
 	if (IS_ERR(left))
 		left = NULL;
 
@@ -1917,7 +1917,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 		}
 	}
 
-	right = read_node_slot(parent, pslot + 1);
+	right = btrfs_read_node_slot(parent, pslot + 1);
 	if (IS_ERR(right))
 		right = NULL;
 
@@ -2077,7 +2077,7 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
 	if (!parent)
 		return 1;
 
-	left = read_node_slot(parent, pslot - 1);
+	left = btrfs_read_node_slot(parent, pslot - 1);
 	if (IS_ERR(left))
 		left = NULL;
 
@@ -2129,7 +2129,7 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
 		btrfs_tree_unlock(left);
 		free_extent_buffer(left);
 	}
-	right = read_node_slot(parent, pslot + 1);
+	right = btrfs_read_node_slot(parent, pslot + 1);
 	if (IS_ERR(right))
 		right = NULL;
 
@@ -3783,7 +3783,7 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
 
 	btrfs_assert_tree_locked(path->nodes[1]);
 
-	right = read_node_slot(upper, slot + 1);
+	right = btrfs_read_node_slot(upper, slot + 1);
 	/*
 	 * slot + 1 is not valid or we fail to read the right node,
 	 * no big deal, just return.
@@ -4017,7 +4017,7 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
 
 	btrfs_assert_tree_locked(path->nodes[1]);
 
-	left = read_node_slot(path->nodes[1], slot - 1);
+	left = btrfs_read_node_slot(path->nodes[1], slot - 1);
 	/*
 	 * slot - 1 is not valid or we fail to read the left node,
 	 * no big deal, just return.
@@ -5224,7 +5224,7 @@ int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key,
 			goto out;
 		}
 		btrfs_set_path_blocking(path);
-		cur = read_node_slot(cur, slot);
+		cur = btrfs_read_node_slot(cur, slot);
 		if (IS_ERR(cur)) {
 			ret = PTR_ERR(cur);
 			goto out;
@@ -5251,7 +5251,7 @@ static int tree_move_down(struct btrfs_path *path, int *level)
 	struct extent_buffer *eb;
 
 	BUG_ON(*level == 0);
-	eb = read_node_slot(path->nodes[*level], path->slots[*level]);
+	eb = btrfs_read_node_slot(path->nodes[*level], path->slots[*level]);
 	if (IS_ERR(eb))
 		return PTR_ERR(eb);
 
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index a7291e7dd574..70a80db23ecc 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2586,6 +2586,9 @@ int btrfs_find_next_key(struct btrfs_root *root, struct btrfs_path *path,
 int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key,
 			 struct btrfs_path *path,
 			 u64 min_trans);
+struct extent_buffer *btrfs_read_node_slot(struct extent_buffer *parent,
+					   int slot);
+
 enum btrfs_compare_tree_result {
 	BTRFS_COMPARE_TREE_NEW,
 	BTRFS_COMPARE_TREE_DELETED,
-- 
2.22.0

[PATCH 5/7] btrfs: move functions for tree compare to send.c

[David Sterba]

Send is the only user of tree_compare, we can move it there along with
the other helpers and definitions.

Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/ctree.c | 362 ---------------------------------------------
 fs/btrfs/ctree.h |  14 --
 fs/btrfs/send.c  | 374 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 374 insertions(+), 376 deletions(-)

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 3b585f3e4d11..fbf94e28fba8 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -5246,368 +5246,6 @@ int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key,
 	return ret;
 }
 
-static int tree_move_down(struct btrfs_path *path, int *level)
-{
-	struct extent_buffer *eb;
-
-	BUG_ON(*level == 0);
-	eb = btrfs_read_node_slot(path->nodes[*level], path->slots[*level]);
-	if (IS_ERR(eb))
-		return PTR_ERR(eb);
-
-	path->nodes[*level - 1] = eb;
-	path->slots[*level - 1] = 0;
-	(*level)--;
-	return 0;
-}
-
-static int tree_move_next_or_upnext(struct btrfs_path *path,
-				    int *level, int root_level)
-{
-	int ret = 0;
-	int nritems;
-	nritems = btrfs_header_nritems(path->nodes[*level]);
-
-	path->slots[*level]++;
-
-	while (path->slots[*level] >= nritems) {
-		if (*level == root_level)
-			return -1;
-
-		/* move upnext */
-		path->slots[*level] = 0;
-		free_extent_buffer(path->nodes[*level]);
-		path->nodes[*level] = NULL;
-		(*level)++;
-		path->slots[*level]++;
-
-		nritems = btrfs_header_nritems(path->nodes[*level]);
-		ret = 1;
-	}
-	return ret;
-}
-
-/*
- * Returns 1 if it had to move up and next. 0 is returned if it moved only next
- * or down.
- */
-static int tree_advance(struct btrfs_path *path,
-			int *level, int root_level,
-			int allow_down,
-			struct btrfs_key *key)
-{
-	int ret;
-
-	if (*level == 0 || !allow_down) {
-		ret = tree_move_next_or_upnext(path, level, root_level);
-	} else {
-		ret = tree_move_down(path, level);
-	}
-	if (ret >= 0) {
-		if (*level == 0)
-			btrfs_item_key_to_cpu(path->nodes[*level], key,
-					path->slots[*level]);
-		else
-			btrfs_node_key_to_cpu(path->nodes[*level], key,
-					path->slots[*level]);
-	}
-	return ret;
-}
-
-static int tree_compare_item(struct btrfs_path *left_path,
-			     struct btrfs_path *right_path,
-			     char *tmp_buf)
-{
-	int cmp;
-	int len1, len2;
-	unsigned long off1, off2;
-
-	len1 = btrfs_item_size_nr(left_path->nodes[0], left_path->slots[0]);
-	len2 = btrfs_item_size_nr(right_path->nodes[0], right_path->slots[0]);
-	if (len1 != len2)
-		return 1;
-
-	off1 = btrfs_item_ptr_offset(left_path->nodes[0], left_path->slots[0]);
-	off2 = btrfs_item_ptr_offset(right_path->nodes[0],
-				right_path->slots[0]);
-
-	read_extent_buffer(left_path->nodes[0], tmp_buf, off1, len1);
-
-	cmp = memcmp_extent_buffer(right_path->nodes[0], tmp_buf, off2, len1);
-	if (cmp)
-		return 1;
-	return 0;
-}
-
-#define ADVANCE 1
-#define ADVANCE_ONLY_NEXT -1
-
-/*
- * This function compares two trees and calls the provided callback for
- * every changed/new/deleted item it finds.
- * If shared tree blocks are encountered, whole subtrees are skipped, making
- * the compare pretty fast on snapshotted subvolumes.
- *
- * This currently works on commit roots only. As commit roots are read only,
- * we don't do any locking. The commit roots are protected with transactions.
- * Transactions are ended and rejoined when a commit is tried in between.
- *
- * This function checks for modifications done to the trees while comparing.
- * If it detects a change, it aborts immediately.
- */
-int btrfs_compare_trees(struct btrfs_root *left_root,
-			struct btrfs_root *right_root,
-			btrfs_changed_cb_t changed_cb, void *ctx)
-{
-	struct btrfs_fs_info *fs_info = left_root->fs_info;
-	int ret;
-	int cmp;
-	struct btrfs_path *left_path = NULL;
-	struct btrfs_path *right_path = NULL;
-	struct btrfs_key left_key;
-	struct btrfs_key right_key;
-	char *tmp_buf = NULL;
-	int left_root_level;
-	int right_root_level;
-	int left_level;
-	int right_level;
-	int left_end_reached;
-	int right_end_reached;
-	int advance_left;
-	int advance_right;
-	u64 left_blockptr;
-	u64 right_blockptr;
-	u64 left_gen;
-	u64 right_gen;
-
-	left_path = btrfs_alloc_path();
-	if (!left_path) {
-		ret = -ENOMEM;
-		goto out;
-	}
-	right_path = btrfs_alloc_path();
-	if (!right_path) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	tmp_buf = kvmalloc(fs_info->nodesize, GFP_KERNEL);
-	if (!tmp_buf) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	left_path->search_commit_root = 1;
-	left_path->skip_locking = 1;
-	right_path->search_commit_root = 1;
-	right_path->skip_locking = 1;
-
-	/*
-	 * Strategy: Go to the first items of both trees. Then do
-	 *
-	 * If both trees are at level 0
-	 *   Compare keys of current items
-	 *     If left < right treat left item as new, advance left tree
-	 *       and repeat
-	 *     If left > right treat right item as deleted, advance right tree
-	 *       and repeat
-	 *     If left == right do deep compare of items, treat as changed if
-	 *       needed, advance both trees and repeat
-	 * If both trees are at the same level but not at level 0
-	 *   Compare keys of current nodes/leafs
-	 *     If left < right advance left tree and repeat
-	 *     If left > right advance right tree and repeat
-	 *     If left == right compare blockptrs of the next nodes/leafs
-	 *       If they match advance both trees but stay at the same level
-	 *         and repeat
-	 *       If they don't match advance both trees while allowing to go
-	 *         deeper and repeat
-	 * If tree levels are different
-	 *   Advance the tree that needs it and repeat
-	 *
-	 * Advancing a tree means:
-	 *   If we are at level 0, try to go to the next slot. If that's not
-	 *   possible, go one level up and repeat. Stop when we found a level
-	 *   where we could go to the next slot. We may at this point be on a
-	 *   node or a leaf.
-	 *
-	 *   If we are not at level 0 and not on shared tree blocks, go one
-	 *   level deeper.
-	 *
-	 *   If we are not at level 0 and on shared tree blocks, go one slot to
-	 *   the right if possible or go up and right.
-	 */
-
-	down_read(&fs_info->commit_root_sem);
-	left_level = btrfs_header_level(left_root->commit_root);
-	left_root_level = left_level;
-	left_path->nodes[left_level] =
-			btrfs_clone_extent_buffer(left_root->commit_root);
-	if (!left_path->nodes[left_level]) {
-		up_read(&fs_info->commit_root_sem);
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	right_level = btrfs_header_level(right_root->commit_root);
-	right_root_level = right_level;
-	right_path->nodes[right_level] =
-			btrfs_clone_extent_buffer(right_root->commit_root);
-	if (!right_path->nodes[right_level]) {
-		up_read(&fs_info->commit_root_sem);
-		ret = -ENOMEM;
-		goto out;
-	}
-	up_read(&fs_info->commit_root_sem);
-
-	if (left_level == 0)
-		btrfs_item_key_to_cpu(left_path->nodes[left_level],
-				&left_key, left_path->slots[left_level]);
-	else
-		btrfs_node_key_to_cpu(left_path->nodes[left_level],
-				&left_key, left_path->slots[left_level]);
-	if (right_level == 0)
-		btrfs_item_key_to_cpu(right_path->nodes[right_level],
-				&right_key, right_path->slots[right_level]);
-	else
-		btrfs_node_key_to_cpu(right_path->nodes[right_level],
-				&right_key, right_path->slots[right_level]);
-
-	left_end_reached = right_end_reached = 0;
-	advance_left = advance_right = 0;
-
-	while (1) {
-		if (advance_left && !left_end_reached) {
-			ret = tree_advance(left_path, &left_level,
-					left_root_level,
-					advance_left != ADVANCE_ONLY_NEXT,
-					&left_key);
-			if (ret == -1)
-				left_end_reached = ADVANCE;
-			else if (ret < 0)
-				goto out;
-			advance_left = 0;
-		}
-		if (advance_right && !right_end_reached) {
-			ret = tree_advance(right_path, &right_level,
-					right_root_level,
-					advance_right != ADVANCE_ONLY_NEXT,
-					&right_key);
-			if (ret == -1)
-				right_end_reached = ADVANCE;
-			else if (ret < 0)
-				goto out;
-			advance_right = 0;
-		}
-
-		if (left_end_reached && right_end_reached) {
-			ret = 0;
-			goto out;
-		} else if (left_end_reached) {
-			if (right_level == 0) {
-				ret = changed_cb(left_path, right_path,
-						&right_key,
-						BTRFS_COMPARE_TREE_DELETED,
-						ctx);
-				if (ret < 0)
-					goto out;
-			}
-			advance_right = ADVANCE;
-			continue;
-		} else if (right_end_reached) {
-			if (left_level == 0) {
-				ret = changed_cb(left_path, right_path,
-						&left_key,
-						BTRFS_COMPARE_TREE_NEW,
-						ctx);
-				if (ret < 0)
-					goto out;
-			}
-			advance_left = ADVANCE;
-			continue;
-		}
-
-		if (left_level == 0 && right_level == 0) {
-			cmp = btrfs_comp_cpu_keys(&left_key, &right_key);
-			if (cmp < 0) {
-				ret = changed_cb(left_path, right_path,
-						&left_key,
-						BTRFS_COMPARE_TREE_NEW,
-						ctx);
-				if (ret < 0)
-					goto out;
-				advance_left = ADVANCE;
-			} else if (cmp > 0) {
-				ret = changed_cb(left_path, right_path,
-						&right_key,
-						BTRFS_COMPARE_TREE_DELETED,
-						ctx);
-				if (ret < 0)
-					goto out;
-				advance_right = ADVANCE;
-			} else {
-				enum btrfs_compare_tree_result result;
-
-				WARN_ON(!extent_buffer_uptodate(left_path->nodes[0]));
-				ret = tree_compare_item(left_path, right_path,
-							tmp_buf);
-				if (ret)
-					result = BTRFS_COMPARE_TREE_CHANGED;
-				else
-					result = BTRFS_COMPARE_TREE_SAME;
-				ret = changed_cb(left_path, right_path,
-						 &left_key, result, ctx);
-				if (ret < 0)
-					goto out;
-				advance_left = ADVANCE;
-				advance_right = ADVANCE;
-			}
-		} else if (left_level == right_level) {
-			cmp = btrfs_comp_cpu_keys(&left_key, &right_key);
-			if (cmp < 0) {
-				advance_left = ADVANCE;
-			} else if (cmp > 0) {
-				advance_right = ADVANCE;
-			} else {
-				left_blockptr = btrfs_node_blockptr(
-						left_path->nodes[left_level],
-						left_path->slots[left_level]);
-				right_blockptr = btrfs_node_blockptr(
-						right_path->nodes[right_level],
-						right_path->slots[right_level]);
-				left_gen = btrfs_node_ptr_generation(
-						left_path->nodes[left_level],
-						left_path->slots[left_level]);
-				right_gen = btrfs_node_ptr_generation(
-						right_path->nodes[right_level],
-						right_path->slots[right_level]);
-				if (left_blockptr == right_blockptr &&
-				    left_gen == right_gen) {
-					/*
-					 * As we're on a shared block, don't
-					 * allow to go deeper.
-					 */
-					advance_left = ADVANCE_ONLY_NEXT;
-					advance_right = ADVANCE_ONLY_NEXT;
-				} else {
-					advance_left = ADVANCE;
-					advance_right = ADVANCE;
-				}
-			}
-		} else if (left_level < right_level) {
-			advance_right = ADVANCE;
-		} else {
-			advance_left = ADVANCE;
-		}
-	}
-
-out:
-	btrfs_free_path(left_path);
-	btrfs_free_path(right_path);
-	kvfree(tmp_buf);
-	return ret;
-}
-
 /*
  * this is similar to btrfs_next_leaf, but does not try to preserve
  * and fixup the path.  It looks for and returns the next key in the
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 70a80db23ecc..1fd5931a9489 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2589,20 +2589,6 @@ int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key,
 struct extent_buffer *btrfs_read_node_slot(struct extent_buffer *parent,
 					   int slot);
 
-enum btrfs_compare_tree_result {
-	BTRFS_COMPARE_TREE_NEW,
-	BTRFS_COMPARE_TREE_DELETED,
-	BTRFS_COMPARE_TREE_CHANGED,
-	BTRFS_COMPARE_TREE_SAME,
-};
-typedef int (*btrfs_changed_cb_t)(struct btrfs_path *left_path,
-				  struct btrfs_path *right_path,
-				  struct btrfs_key *key,
-				  enum btrfs_compare_tree_result result,
-				  void *ctx);
-int btrfs_compare_trees(struct btrfs_root *left_root,
-			struct btrfs_root *right_root,
-			btrfs_changed_cb_t cb, void *ctx);
 int btrfs_cow_block(struct btrfs_trans_handle *trans,
 		    struct btrfs_root *root, struct extent_buffer *buf,
 		    struct extent_buffer *parent, int parent_slot,
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index c3c0c064c25d..f856d6ca3771 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -260,6 +260,21 @@ struct name_cache_entry {
 	char name[];
 };
 
+#define ADVANCE							1
+#define ADVANCE_ONLY_NEXT					-1
+
+enum btrfs_compare_tree_result {
+	BTRFS_COMPARE_TREE_NEW,
+	BTRFS_COMPARE_TREE_DELETED,
+	BTRFS_COMPARE_TREE_CHANGED,
+	BTRFS_COMPARE_TREE_SAME,
+};
+typedef int (*btrfs_changed_cb_t)(struct btrfs_path *left_path,
+				  struct btrfs_path *right_path,
+				  struct btrfs_key *key,
+				  enum btrfs_compare_tree_result result,
+				  void *ctx);
+
 __cold
 static void inconsistent_snapshot_error(struct send_ctx *sctx,
 					enum btrfs_compare_tree_result result,
@@ -6514,6 +6529,365 @@ static int full_send_tree(struct send_ctx *sctx)
 	return ret;
 }
 
+static int tree_move_down(struct btrfs_path *path, int *level)
+{
+	struct extent_buffer *eb;
+
+	BUG_ON(*level == 0);
+	eb = btrfs_read_node_slot(path->nodes[*level], path->slots[*level]);
+	if (IS_ERR(eb))
+		return PTR_ERR(eb);
+
+	path->nodes[*level - 1] = eb;
+	path->slots[*level - 1] = 0;
+	(*level)--;
+	return 0;
+}
+
+static int tree_move_next_or_upnext(struct btrfs_path *path,
+				    int *level, int root_level)
+{
+	int ret = 0;
+	int nritems;
+	nritems = btrfs_header_nritems(path->nodes[*level]);
+
+	path->slots[*level]++;
+
+	while (path->slots[*level] >= nritems) {
+		if (*level == root_level)
+			return -1;
+
+		/* move upnext */
+		path->slots[*level] = 0;
+		free_extent_buffer(path->nodes[*level]);
+		path->nodes[*level] = NULL;
+		(*level)++;
+		path->slots[*level]++;
+
+		nritems = btrfs_header_nritems(path->nodes[*level]);
+		ret = 1;
+	}
+	return ret;
+}
+
+/*
+ * Returns 1 if it had to move up and next. 0 is returned if it moved only next
+ * or down.
+ */
+static int tree_advance(struct btrfs_path *path,
+			int *level, int root_level,
+			int allow_down,
+			struct btrfs_key *key)
+{
+	int ret;
+
+	if (*level == 0 || !allow_down) {
+		ret = tree_move_next_or_upnext(path, level, root_level);
+	} else {
+		ret = tree_move_down(path, level);
+	}
+	if (ret >= 0) {
+		if (*level == 0)
+			btrfs_item_key_to_cpu(path->nodes[*level], key,
+					path->slots[*level]);
+		else
+			btrfs_node_key_to_cpu(path->nodes[*level], key,
+					path->slots[*level]);
+	}
+	return ret;
+}
+
+static int tree_compare_item(struct btrfs_path *left_path,
+			     struct btrfs_path *right_path,
+			     char *tmp_buf)
+{
+	int cmp;
+	int len1, len2;
+	unsigned long off1, off2;
+
+	len1 = btrfs_item_size_nr(left_path->nodes[0], left_path->slots[0]);
+	len2 = btrfs_item_size_nr(right_path->nodes[0], right_path->slots[0]);
+	if (len1 != len2)
+		return 1;
+
+	off1 = btrfs_item_ptr_offset(left_path->nodes[0], left_path->slots[0]);
+	off2 = btrfs_item_ptr_offset(right_path->nodes[0],
+				right_path->slots[0]);
+
+	read_extent_buffer(left_path->nodes[0], tmp_buf, off1, len1);
+
+	cmp = memcmp_extent_buffer(right_path->nodes[0], tmp_buf, off2, len1);
+	if (cmp)
+		return 1;
+	return 0;
+}
+
+/*
+ * This function compares two trees and calls the provided callback for
+ * every changed/new/deleted item it finds.
+ * If shared tree blocks are encountered, whole subtrees are skipped, making
+ * the compare pretty fast on snapshotted subvolumes.
+ *
+ * This currently works on commit roots only. As commit roots are read only,
+ * we don't do any locking. The commit roots are protected with transactions.
+ * Transactions are ended and rejoined when a commit is tried in between.
+ *
+ * This function checks for modifications done to the trees while comparing.
+ * If it detects a change, it aborts immediately.
+ */
+static int btrfs_compare_trees(struct btrfs_root *left_root,
+			struct btrfs_root *right_root,
+			btrfs_changed_cb_t changed_cb, void *ctx)
+{
+	struct btrfs_fs_info *fs_info = left_root->fs_info;
+	int ret;
+	int cmp;
+	struct btrfs_path *left_path = NULL;
+	struct btrfs_path *right_path = NULL;
+	struct btrfs_key left_key;
+	struct btrfs_key right_key;
+	char *tmp_buf = NULL;
+	int left_root_level;
+	int right_root_level;
+	int left_level;
+	int right_level;
+	int left_end_reached;
+	int right_end_reached;
+	int advance_left;
+	int advance_right;
+	u64 left_blockptr;
+	u64 right_blockptr;
+	u64 left_gen;
+	u64 right_gen;
+
+	left_path = btrfs_alloc_path();
+	if (!left_path) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	right_path = btrfs_alloc_path();
+	if (!right_path) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	tmp_buf = kvmalloc(fs_info->nodesize, GFP_KERNEL);
+	if (!tmp_buf) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	left_path->search_commit_root = 1;
+	left_path->skip_locking = 1;
+	right_path->search_commit_root = 1;
+	right_path->skip_locking = 1;
+
+	/*
+	 * Strategy: Go to the first items of both trees. Then do
+	 *
+	 * If both trees are at level 0
+	 *   Compare keys of current items
+	 *     If left < right treat left item as new, advance left tree
+	 *       and repeat
+	 *     If left > right treat right item as deleted, advance right tree
+	 *       and repeat
+	 *     If left == right do deep compare of items, treat as changed if
+	 *       needed, advance both trees and repeat
+	 * If both trees are at the same level but not at level 0
+	 *   Compare keys of current nodes/leafs
+	 *     If left < right advance left tree and repeat
+	 *     If left > right advance right tree and repeat
+	 *     If left == right compare blockptrs of the next nodes/leafs
+	 *       If they match advance both trees but stay at the same level
+	 *         and repeat
+	 *       If they don't match advance both trees while allowing to go
+	 *         deeper and repeat
+	 * If tree levels are different
+	 *   Advance the tree that needs it and repeat
+	 *
+	 * Advancing a tree means:
+	 *   If we are at level 0, try to go to the next slot. If that's not
+	 *   possible, go one level up and repeat. Stop when we found a level
+	 *   where we could go to the next slot. We may at this point be on a
+	 *   node or a leaf.
+	 *
+	 *   If we are not at level 0 and not on shared tree blocks, go one
+	 *   level deeper.
+	 *
+	 *   If we are not at level 0 and on shared tree blocks, go one slot to
+	 *   the right if possible or go up and right.
+	 */
+
+	down_read(&fs_info->commit_root_sem);
+	left_level = btrfs_header_level(left_root->commit_root);
+	left_root_level = left_level;
+	left_path->nodes[left_level] =
+			btrfs_clone_extent_buffer(left_root->commit_root);
+	if (!left_path->nodes[left_level]) {
+		up_read(&fs_info->commit_root_sem);
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	right_level = btrfs_header_level(right_root->commit_root);
+	right_root_level = right_level;
+	right_path->nodes[right_level] =
+			btrfs_clone_extent_buffer(right_root->commit_root);
+	if (!right_path->nodes[right_level]) {
+		up_read(&fs_info->commit_root_sem);
+		ret = -ENOMEM;
+		goto out;
+	}
+	up_read(&fs_info->commit_root_sem);
+
+	if (left_level == 0)
+		btrfs_item_key_to_cpu(left_path->nodes[left_level],
+				&left_key, left_path->slots[left_level]);
+	else
+		btrfs_node_key_to_cpu(left_path->nodes[left_level],
+				&left_key, left_path->slots[left_level]);
+	if (right_level == 0)
+		btrfs_item_key_to_cpu(right_path->nodes[right_level],
+				&right_key, right_path->slots[right_level]);
+	else
+		btrfs_node_key_to_cpu(right_path->nodes[right_level],
+				&right_key, right_path->slots[right_level]);
+
+	left_end_reached = right_end_reached = 0;
+	advance_left = advance_right = 0;
+
+	while (1) {
+		if (advance_left && !left_end_reached) {
+			ret = tree_advance(left_path, &left_level,
+					left_root_level,
+					advance_left != ADVANCE_ONLY_NEXT,
+					&left_key);
+			if (ret == -1)
+				left_end_reached = ADVANCE;
+			else if (ret < 0)
+				goto out;
+			advance_left = 0;
+		}
+		if (advance_right && !right_end_reached) {
+			ret = tree_advance(right_path, &right_level,
+					right_root_level,
+					advance_right != ADVANCE_ONLY_NEXT,
+					&right_key);
+			if (ret == -1)
+				right_end_reached = ADVANCE;
+			else if (ret < 0)
+				goto out;
+			advance_right = 0;
+		}
+
+		if (left_end_reached && right_end_reached) {
+			ret = 0;
+			goto out;
+		} else if (left_end_reached) {
+			if (right_level == 0) {
+				ret = changed_cb(left_path, right_path,
+						&right_key,
+						BTRFS_COMPARE_TREE_DELETED,
+						ctx);
+				if (ret < 0)
+					goto out;
+			}
+			advance_right = ADVANCE;
+			continue;
+		} else if (right_end_reached) {
+			if (left_level == 0) {
+				ret = changed_cb(left_path, right_path,
+						&left_key,
+						BTRFS_COMPARE_TREE_NEW,
+						ctx);
+				if (ret < 0)
+					goto out;
+			}
+			advance_left = ADVANCE;
+			continue;
+		}
+
+		if (left_level == 0 && right_level == 0) {
+			cmp = btrfs_comp_cpu_keys(&left_key, &right_key);
+			if (cmp < 0) {
+				ret = changed_cb(left_path, right_path,
+						&left_key,
+						BTRFS_COMPARE_TREE_NEW,
+						ctx);
+				if (ret < 0)
+					goto out;
+				advance_left = ADVANCE;
+			} else if (cmp > 0) {
+				ret = changed_cb(left_path, right_path,
+						&right_key,
+						BTRFS_COMPARE_TREE_DELETED,
+						ctx);
+				if (ret < 0)
+					goto out;
+				advance_right = ADVANCE;
+			} else {
+				enum btrfs_compare_tree_result result;
+
+				WARN_ON(!extent_buffer_uptodate(left_path->nodes[0]));
+				ret = tree_compare_item(left_path, right_path,
+							tmp_buf);
+				if (ret)
+					result = BTRFS_COMPARE_TREE_CHANGED;
+				else
+					result = BTRFS_COMPARE_TREE_SAME;
+				ret = changed_cb(left_path, right_path,
+						 &left_key, result, ctx);
+				if (ret < 0)
+					goto out;
+				advance_left = ADVANCE;
+				advance_right = ADVANCE;
+			}
+		} else if (left_level == right_level) {
+			cmp = btrfs_comp_cpu_keys(&left_key, &right_key);
+			if (cmp < 0) {
+				advance_left = ADVANCE;
+			} else if (cmp > 0) {
+				advance_right = ADVANCE;
+			} else {
+				left_blockptr = btrfs_node_blockptr(
+						left_path->nodes[left_level],
+						left_path->slots[left_level]);
+				right_blockptr = btrfs_node_blockptr(
+						right_path->nodes[right_level],
+						right_path->slots[right_level]);
+				left_gen = btrfs_node_ptr_generation(
+						left_path->nodes[left_level],
+						left_path->slots[left_level]);
+				right_gen = btrfs_node_ptr_generation(
+						right_path->nodes[right_level],
+						right_path->slots[right_level]);
+				if (left_blockptr == right_blockptr &&
+				    left_gen == right_gen) {
+					/*
+					 * As we're on a shared block, don't
+					 * allow to go deeper.
+					 */
+					advance_left = ADVANCE_ONLY_NEXT;
+					advance_right = ADVANCE_ONLY_NEXT;
+				} else {
+					advance_left = ADVANCE;
+					advance_right = ADVANCE;
+				}
+			}
+		} else if (left_level < right_level) {
+			advance_right = ADVANCE;
+		} else {
+			advance_left = ADVANCE;
+		}
+	}
+
+out:
+	btrfs_free_path(left_path);
+	btrfs_free_path(right_path);
+	kvfree(tmp_buf);
+	return ret;
+}
+
 static int send_subvol(struct send_ctx *sctx)
 {
 	int ret;
-- 
2.22.0

[PATCH 6/7] btrfs: move struct io_ctl to free-space-cache.h

[David Sterba]

The io_ctl structure is used for free space management, and used only by
the v1 space cache code, but unfortunatlly the full definition is
required by block-group.h so it can't be moved to free-space-cache.c
without additional changes.

Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/block-group.h      |  2 ++
 fs/btrfs/ctree.h            | 14 --------------
 fs/btrfs/free-space-cache.h | 14 +++++++++++++-
 3 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/fs/btrfs/block-group.h b/fs/btrfs/block-group.h
index 5c6e2fb23e35..c391800388dd 100644
--- a/fs/btrfs/block-group.h
+++ b/fs/btrfs/block-group.h
@@ -3,6 +3,8 @@
 #ifndef BTRFS_BLOCK_GROUP_H
 #define BTRFS_BLOCK_GROUP_H
 
+#include "free-space-cache.h"
+
 enum btrfs_disk_cache_state {
 	BTRFS_DC_WRITTEN,
 	BTRFS_DC_ERROR,
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 1fd5931a9489..5977995b1b69 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -433,20 +433,6 @@ enum btrfs_caching_type {
 	BTRFS_CACHE_ERROR,
 };
 
-struct btrfs_io_ctl {
-	void *cur, *orig;
-	struct page *page;
-	struct page **pages;
-	struct btrfs_fs_info *fs_info;
-	struct inode *inode;
-	unsigned long size;
-	int index;
-	int num_pages;
-	int entries;
-	int bitmaps;
-	unsigned check_crcs:1;
-};
-
 /*
  * Tree to record all locked full stripes of a RAID5/6 block group
  */
diff --git a/fs/btrfs/free-space-cache.h b/fs/btrfs/free-space-cache.h
index 2205a4113ef3..39c32c8fc24f 100644
--- a/fs/btrfs/free-space-cache.h
+++ b/fs/btrfs/free-space-cache.h
@@ -36,7 +36,19 @@ struct btrfs_free_space_op {
 			   struct btrfs_free_space *info);
 };
 
-struct btrfs_io_ctl;
+struct btrfs_io_ctl {
+	void *cur, *orig;
+	struct page *page;
+	struct page **pages;
+	struct btrfs_fs_info *fs_info;
+	struct inode *inode;
+	unsigned long size;
+	int index;
+	int num_pages;
+	int entries;
+	int bitmaps;
+	unsigned check_crcs:1;
+};
 
 struct inode *lookup_free_space_inode(
 		struct btrfs_block_group_cache *block_group,
-- 
2.22.0

[PATCH 7/7] btrfs: move dev_stats helpers to volumes.c

[David Sterba]

The other dev stats functions are already there and the helpers are not
used by anything else.

Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/ctree.h   | 24 ------------------------
 fs/btrfs/volumes.c | 23 +++++++++++++++++++++++
 2 files changed, 23 insertions(+), 24 deletions(-)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 5977995b1b69..35a94a43758d 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2257,30 +2257,6 @@ static inline u32 btrfs_file_extent_inline_item_len(
 	return btrfs_item_size(eb, e) - BTRFS_FILE_EXTENT_INLINE_DATA_START;
 }
 
-/* btrfs_dev_stats_item */
-static inline u64 btrfs_dev_stats_value(const struct extent_buffer *eb,
-					const struct btrfs_dev_stats_item *ptr,
-					int index)
-{
-	u64 val;
-
-	read_extent_buffer(eb, &val,
-			   offsetof(struct btrfs_dev_stats_item, values) +
-			    ((unsigned long)ptr) + (index * sizeof(u64)),
-			   sizeof(val));
-	return val;
-}
-
-static inline void btrfs_set_dev_stats_value(struct extent_buffer *eb,
-					     struct btrfs_dev_stats_item *ptr,
-					     int index, u64 val)
-{
-	write_extent_buffer(eb, &val,
-			    offsetof(struct btrfs_dev_stats_item, values) +
-			     ((unsigned long)ptr) + (index * sizeof(u64)),
-			    sizeof(val));
-}
-
 /* btrfs_qgroup_status_item */
 BTRFS_SETGET_FUNCS(qgroup_status_generation, struct btrfs_qgroup_status_item,
 		   generation, 64);
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index dc1f6985c2c4..104fa1c2afb0 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -7276,6 +7276,29 @@ void btrfs_init_devices_late(struct btrfs_fs_info *fs_info)
 	}
 }
 
+static u64 btrfs_dev_stats_value(const struct extent_buffer *eb,
+				 const struct btrfs_dev_stats_item *ptr,
+				 int index)
+{
+	u64 val;
+
+	read_extent_buffer(eb, &val,
+			   offsetof(struct btrfs_dev_stats_item, values) +
+			    ((unsigned long)ptr) + (index * sizeof(u64)),
+			   sizeof(val));
+	return val;
+}
+
+static void btrfs_set_dev_stats_value(struct extent_buffer *eb,
+				      struct btrfs_dev_stats_item *ptr,
+				      int index, u64 val)
+{
+	write_extent_buffer(eb, &val,
+			    offsetof(struct btrfs_dev_stats_item, values) +
+			     ((unsigned long)ptr) + (index * sizeof(u64)),
+			    sizeof(val));
+}
+
 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
 {
 	struct btrfs_key key;
-- 
2.22.0

Re: [PATCH 1/7] btrfs: move cond_wake_up functions out of ctree

[Johannes Thumshirn]

Looks good,
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
-- 
Johannes Thumshirn                            SUSE Labs Filesystems
jthumshirn@suse.de                                +49 911 74053 689
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5
90409 Nürnberg
Germany
(HRB 247165, AG München)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850

Re: [PATCH 2/7] btrfs: move math functions to misc.h

[Johannes Thumshirn]

> @@ -1,28 +0,0 @@
> -/* SPDX-License-Identifier: GPL-2.0 */
> -/*
> - * Copyright (C) 2012 Fujitsu.  All rights reserved.
> - * Written by Miao Xie <miaox@cn.fujitsu.com>
> - */

This copyright note will get lost with this patch.


-- 
Johannes Thumshirn                            SUSE Labs Filesystems
jthumshirn@suse.de                                +49 911 74053 689
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5
90409 Nürnberg
Germany
(HRB 247165, AG München)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850

Re: [PATCH 3/7] btrfs: move private raid56 definitions from ctree.h

[Johannes Thumshirn]

Looks good,
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
-- 
Johannes Thumshirn                            SUSE Labs Filesystems
jthumshirn@suse.de                                +49 911 74053 689
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5
90409 Nürnberg
Germany
(HRB 247165, AG München)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850

Re: [PATCH 5/7] btrfs: move functions for tree compare to send.c

[Johannes Thumshirn]

Looks good,
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
-- 
Johannes Thumshirn                            SUSE Labs Filesystems
jthumshirn@suse.de                                +49 911 74053 689
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5
90409 Nürnberg
Germany
(HRB 247165, AG München)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850

Re: [PATCH 4/7] btrfs: rename and export read_node_slot

[Johannes Thumshirn]

Looks good,
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
-- 
Johannes Thumshirn                            SUSE Labs Filesystems
jthumshirn@suse.de                                +49 911 74053 689
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5
90409 Nürnberg
Germany
(HRB 247165, AG München)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850

Re: [PATCH 6/7] btrfs: move struct io_ctl to free-space-cache.h

[Johannes Thumshirn]

Looks good,
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
-- 
Johannes Thumshirn                            SUSE Labs Filesystems
jthumshirn@suse.de                                +49 911 74053 689
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5
90409 Nürnberg
Germany
(HRB 247165, AG München)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850

Re: [PATCH 7/7] btrfs: move dev_stats helpers to volumes.c

[Johannes Thumshirn]

Looks good,
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
-- 
Johannes Thumshirn                            SUSE Labs Filesystems
jthumshirn@suse.de                                +49 911 74053 689
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5
90409 Nürnberg
Germany
(HRB 247165, AG München)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850