ocfs2: abstract btree growing calls

The top level calls and logic for growing a tree can easily be abstracted
out of ocfs2_insert_extent() into a seperate function - ocfs2_grow_tree().

This allows future code to easily grow btrees when needed.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index b5327b4cdb34aa34b9714ceb1d149412e02877be..a02d026cb0e429e4ac0e6f097a2377b702f4a96f 100644 (file)
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -824,6 +824,74 @@ bail:
        return status;
 }
 
+/*
+ * Grow a b-tree so that it has more records.
+ *
+ * We might shift the tree depth in which case existing paths should
+ * be considered invalid.
+ *
+ * Tree depth after the grow is returned via *final_depth.
+ */
+static int ocfs2_grow_tree(struct inode *inode, handle_t *handle,
+                          struct buffer_head *di_bh, int *final_depth,
+                          struct buffer_head *last_eb_bh,
+                          struct ocfs2_alloc_context *meta_ac)
+{
+       int ret, shift;
+       struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+       int depth = le16_to_cpu(di->id2.i_list.l_tree_depth);
+       struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+       struct buffer_head *bh = NULL;
+
+       BUG_ON(meta_ac == NULL);
+
+       shift = ocfs2_find_branch_target(osb, inode, di_bh, &bh);
+       if (shift < 0) {
+               ret = shift;
+               mlog_errno(ret);
+               goto out;
+       }
+
+       /* We traveled all the way to the bottom of the allocation tree
+        * and didn't find room for any more extents - we need to add
+        * another tree level */
+       if (shift) {
+               BUG_ON(bh);
+               mlog(0, "need to shift tree depth (current = %d)\n", depth);
+
+               /* ocfs2_shift_tree_depth will return us a buffer with
+                * the new extent block (so we can pass that to
+                * ocfs2_add_branch). */
+               ret = ocfs2_shift_tree_depth(osb, handle, inode, di_bh,
+                                            meta_ac, &bh);
+               if (ret < 0) {
+                       mlog_errno(ret);
+                       goto out;
+               }
+               depth++;
+               /* Special case: we have room now if we shifted from
+                * tree_depth 0 */
+               if (depth == 1)
+                       goto out;
+       }
+
+       /* call ocfs2_add_branch to add the final part of the tree with
+        * the new data. */
+       mlog(0, "add branch. bh = %p\n", bh);
+       ret = ocfs2_add_branch(osb, handle, inode, di_bh, bh, last_eb_bh,
+                              meta_ac);
+       if (ret < 0) {
+               mlog_errno(ret);
+               goto out;
+       }
+
+out:
+       if (final_depth)
+               *final_depth = depth;
+       brelse(bh);
+       return ret;
+}
+
 /*
  * This is only valid for leaf nodes, which are the only ones that can
  * have empty extents anyway.
@@ -2325,7 +2393,7 @@ int ocfs2_insert_extent(struct ocfs2_super *osb,
                        u32 new_clusters,
                        struct ocfs2_alloc_context *meta_ac)
 {
-       int status, shift;
+       int status;
        struct buffer_head *last_eb_bh = NULL;
        struct buffer_head *bh = NULL;
        struct ocfs2_insert_type insert = {0, };
@@ -2360,55 +2428,16 @@ int ocfs2_insert_extent(struct ocfs2_super *osb,
             insert.ins_appending, insert.ins_contig, insert.ins_contig_index,
             insert.ins_free_records, insert.ins_tree_depth);
 
-       /*
-        * Avoid growing the tree unless we're out of records and the
-        * insert type requres one.
-        */
-       if (insert.ins_contig != CONTIG_NONE || insert.ins_free_records)
-               goto out_add;
-
-       shift = ocfs2_find_branch_target(osb, inode, fe_bh, &bh);
-       if (shift < 0) {
-               status = shift;
-               mlog_errno(status);
-               goto bail;
-       }
-
-       /* We traveled all the way to the bottom of the allocation tree
-        * and didn't find room for any more extents - we need to add
-        * another tree level */
-       if (shift) {
-               BUG_ON(bh);
-               mlog(0, "need to shift tree depth "
-                    "(current = %d)\n", insert.ins_tree_depth);
-
-               /* ocfs2_shift_tree_depth will return us a buffer with
-                * the new extent block (so we can pass that to
-                * ocfs2_add_branch). */
-               status = ocfs2_shift_tree_depth(osb, handle, inode, fe_bh,
-                                               meta_ac, &bh);
-               if (status < 0) {
+       if (insert.ins_contig == CONTIG_NONE && insert.ins_free_records == 0) {
+               status = ocfs2_grow_tree(inode, handle, fe_bh,
+                                        &insert.ins_tree_depth, last_eb_bh,
+                                        meta_ac);
+               if (status) {
                        mlog_errno(status);
                        goto bail;
                }
-               insert.ins_tree_depth++;
-               /* Special case: we have room now if we shifted from
-                * tree_depth 0 */
-               if (insert.ins_tree_depth == 1)
-                       goto out_add;
-       }
-
-       /* call ocfs2_add_branch to add the final part of the tree with
-        * the new data. */
-       mlog(0, "add branch. bh = %p\n", bh);
-       status = ocfs2_add_branch(osb, handle, inode, fe_bh, bh, last_eb_bh,
-                                 meta_ac);
-       if (status < 0) {
-               mlog_errno(status);
-               goto bail;
        }
 
-out_add:
        /* Finally, we can add clusters. This might rotate the tree for us. */
        status = ocfs2_do_insert_extent(inode, handle, fe_bh, &rec, &insert);
        if (status < 0)