ocfs2: allow return of new inode block location before allocation of the inode

This allows code which needs to know the eventual block number of an inode
but can't allocate it yet due to transaction or lock ordering. For example,
ocfs2_create_inode_in_orphan() currently gives a junk blkno for preparation
of the orphan dir because it can't yet know where the actual inode is placed
- that code is actually in ocfs2_mknod_locked. This is a problem when the
orphan dirs are indexed as the junk inode number will create an index entry
which goes unused (and fails the later removal from the orphan dir).  Now
with these interfaces, ocfs2_create_inode_in_orphan() can run the block
group search (and get back the inode block number) *before* any actual
allocation occurs.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Tao Ma <tao.ma@oracle.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/fs/ocfs2/suballoc.h b/fs/ocfs2/suballoc.h
index a017dd3ee7d9..b8afabfeede4 100644
--- a/fs/ocfs2/suballoc.h
+++ b/fs/ocfs2/suballoc.h
@@ -56,6 +56,9 @@ struct ocfs2_alloc_context {
         u64    ac_max_block;  /* Highest block number to allocate. 0 is
                                  is the same as ~0 - unlimited */
 
+        int    ac_find_loc_only;  /* hack for reflink operation ordering */
+        struct ocfs2_suballoc_result *ac_find_loc_priv; /* */
+
         struct ocfs2_alloc_reservation  *ac_resv;
 };
 
@@ -197,4 +200,22 @@ int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_extent_tree *et,
                           struct ocfs2_alloc_context **meta_ac);
 
 int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res);
+
+
+
+/*
+ * The following two interfaces are for ocfs2_create_inode_in_orphan().
+ */
+int ocfs2_find_new_inode_loc(struct inode *dir,
+                             struct buffer_head *parent_fe_bh,
+                             struct ocfs2_alloc_context *ac,
+                             u64 *fe_blkno);
+
+int ocfs2_claim_new_inode_at_loc(handle_t *handle,
+                                 struct inode *dir,
+                                 struct ocfs2_alloc_context *ac,
+                                 u64 *suballoc_loc,
+                                 u16 *suballoc_bit,
+                                 u64 di_blkno);
+
 #endif /* _CHAINALLOC_H_ */