ocfs2: Make ocfs2_extent_tree the first-class representation of a tree.

We now have three different kinds of extent trees in ocfs2: inode data
(dinode), extended attributes (xattr_tree), and extended attribute
values (xattr_value).  There is a nice abstraction for them,
ocfs2_extent_tree, but it is hidden in alloc.c.  All the calling
functions have to pick amongst a varied API and pass in type bits and
often extraneous pointers.

A better way is to make ocfs2_extent_tree a first-class object.
Everyone converts their object to an ocfs2_extent_tree() via the
ocfs2_get_*_extent_tree() calls, then uses the ocfs2_extent_tree for all
tree calls to alloc.c.

This simplifies a lot of callers, making for readability.  It also
provides an easy way to add additional extent tree types, as they only
need to be defined in alloc.c with a ocfs2_get_<new>_extent_tree()
function.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

1 files changed, 10 insertions, 6 deletions

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 530b1ff599c0..ed937fa9e4e3 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -1242,6 +1242,7 @@ static int ocfs2_write_cluster(struct address_space *mapping,
         int ret, i, new, should_zero = 0;
         u64 v_blkno, p_blkno;
         struct inode *inode = mapping->host;
+        struct ocfs2_extent_tree et;
 
         new = phys == 0 ? 1 : 0;
         if (new || unwritten)
@@ -1276,10 +1277,11 @@ static int ocfs2_write_cluster(struct address_space *mapping,
                         goto out;
                 }
         } else if (unwritten) {
-                ret = ocfs2_mark_extent_written(inode, wc->w_di_bh,
+                ocfs2_get_dinode_extent_tree(&et, inode, wc->w_di_bh);
+                ret = ocfs2_mark_extent_written(inode, &et,
                                                 wc->w_handle, cpos, 1, phys,
-                                                meta_ac, &wc->w_dealloc,
-                                                OCFS2_DINODE_EXTENT, NULL);
+                                                meta_ac, &wc->w_dealloc);
+                ocfs2_put_extent_tree(&et);
                 if (ret < 0) {
                         mlog_errno(ret);
                         goto out;
@@ -1666,6 +1668,7 @@ int ocfs2_write_begin_nolock(struct address_space *mapping,
         struct ocfs2_alloc_context *data_ac = NULL;
         struct ocfs2_alloc_context *meta_ac = NULL;
         handle_t *handle;
+        struct ocfs2_extent_tree et;
 
         ret = ocfs2_alloc_write_ctxt(&wc, osb, pos, len, di_bh);
         if (ret) {
@@ -1719,10 +1722,11 @@ int ocfs2_write_begin_nolock(struct address_space *mapping,
                      (long long)i_size_read(inode), le32_to_cpu(di->i_clusters),
                      clusters_to_alloc, extents_to_split);
 
-                ret = ocfs2_lock_allocators(inode, wc->w_di_bh, &di->id2.i_list,
+                ocfs2_get_dinode_extent_tree(&et, inode, wc->w_di_bh);
+                ret = ocfs2_lock_allocators(inode, &et,
                                             clusters_to_alloc, extents_to_split,
-                                            &data_ac, &meta_ac,
-                                            OCFS2_DINODE_EXTENT, NULL);
+                                            &data_ac, &meta_ac);
+                ocfs2_put_extent_tree(&et);
                 if (ret) {
                         mlog_errno(ret);
                         goto out;