btrfs: temporarily export alloc_extent_state helpers

We're going to move this code in stages, but while we're doing that we
need to export these helpers so we can more easily move the code into
the new file.
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/extent-io-tree.h

@@ -250,4 +250,7 @@ void btrfs_free_io_failure_record(struct btrfs_inode *inode, u64 start,
 int btrfs_clean_io_failure(struct btrfs_inode *inode, u64 start,
 			   struct page *page, unsigned int pg_offset);
 
+struct extent_state *alloc_extent_state_atomic(struct extent_state *prealloc);
+struct extent_state *alloc_extent_state(gfp_t mask);
+
 #endif /* BTRFS_EXTENT_IO_TREE_H */

fs/btrfs/extent_io.c

@@ -339,7 +339,7 @@ void extent_io_tree_release(struct extent_io_tree *tree)
 	spin_unlock(&tree->lock);
 }
 
-static struct extent_state *alloc_extent_state(gfp_t mask)
+struct extent_state *alloc_extent_state(gfp_t mask)
 {
 	struct extent_state *state;
 
@@ -710,8 +710,7 @@ static struct extent_state *clear_state_bit(struct extent_io_tree *tree,
 	return next;
 }
 
-static struct extent_state *
-alloc_extent_state_atomic(struct extent_state *prealloc)
+struct extent_state *alloc_extent_state_atomic(struct extent_state *prealloc)
 {
 	if (!prealloc)
 		prealloc = alloc_extent_state(GFP_ATOMIC);