btrfs: move btrfs_truncate_inode_items to inode-item.c

This is an inode item related manipulation with a few vfs related
adjustments.  I'm going to remove the vfs related code from this helper
and simplify it a lot, but I want those changes to be easily seen via
git blame, so move this function now and then the simplification work
can be done.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/ctree.h

@@ -3190,10 +3190,6 @@ int btrfs_add_link(struct btrfs_trans_handle *trans,
 int btrfs_delete_subvolume(struct inode *dir, struct dentry *dentry);
 int btrfs_truncate_block(struct btrfs_inode *inode, loff_t from, loff_t len,
 			 int front);
-int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
-			       struct btrfs_root *root,
-			       struct btrfs_inode *inode, u64 new_size,
-			       u32 min_type, u64 *extents_found);
 
 int btrfs_start_delalloc_snapshot(struct btrfs_root *root, bool in_reclaim_context);
 int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, long nr,

fs/btrfs/inode-item.h

@@ -10,8 +10,19 @@ struct btrfs_root;
 struct btrfs_path;
 struct btrfs_key;
 struct btrfs_inode_extref;
+struct btrfs_inode;
 struct extent_buffer;
 
+/*
+ * Return this if we need to call truncate_block for the last bit of the
+ * truncate.
+ */
+#define BTRFS_NEED_TRUNCATE_BLOCK		1
+
+int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
+			       struct btrfs_root *root,
+			       struct btrfs_inode *inode, u64 new_size,
+			       u32 min_type, u64 *extents_found);
 int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans,
 			   struct btrfs_root *root,
 			   const char *name, int name_len,