ocfs2: Make truncating the extent map an extent_tree_operation.

ocfs2_remove_extent() wants to truncate the extent map if it's
truncating an inode data extent.  But since many btrees can call that
function, let's make it an op on ocfs2_extent_tree.  Other tree types
can leave it empty.

Signed-off-by: Joel Becker <joel.becker@oracle.com>

1 files changed, 31 insertions, 6 deletions

diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 4022fa4dffb5..cdf96974a6a2 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -83,6 +83,13 @@ struct ocfs2_extent_tree_operations {
                                    u32 new_clusters);
 
         /*
+         * If this extent tree is supported by an extent map, truncate the
+         * map to clusters,
+         */
+        void (*eo_extent_map_truncate)(struct ocfs2_extent_tree *et,
+                                       u32 clusters);
+
+        /*
          * If ->eo_insert_check() exists, it is called before rec is
          * inserted into the extent tree.  It is optional.
          */
@@ -120,6 +127,8 @@ static void ocfs2_dinode_set_last_eb_blk(struct ocfs2_extent_tree *et,
                                          u64 blkno);
 static void ocfs2_dinode_update_clusters(struct ocfs2_extent_tree *et,
                                          u32 clusters);
+static void ocfs2_dinode_extent_map_truncate(struct ocfs2_extent_tree *et,
+                                             u32 clusters);
 static int ocfs2_dinode_insert_check(struct ocfs2_extent_tree *et,
                                      struct ocfs2_extent_rec *rec);
 static int ocfs2_dinode_sanity_check(struct ocfs2_extent_tree *et);
@@ -128,6 +137,7 @@ static struct ocfs2_extent_tree_operations ocfs2_dinode_et_ops = {
         .eo_set_last_eb_blk     = ocfs2_dinode_set_last_eb_blk,
         .eo_get_last_eb_blk     = ocfs2_dinode_get_last_eb_blk,
         .eo_update_clusters     = ocfs2_dinode_update_clusters,
+        .eo_extent_map_truncate = ocfs2_dinode_extent_map_truncate,
         .eo_insert_check        = ocfs2_dinode_insert_check,
         .eo_sanity_check        = ocfs2_dinode_sanity_check,
         .eo_fill_root_el        = ocfs2_dinode_fill_root_el,
@@ -162,6 +172,14 @@ static void ocfs2_dinode_update_clusters(struct ocfs2_extent_tree *et,
         spin_unlock(&oi->ip_lock);
 }
 
+static void ocfs2_dinode_extent_map_truncate(struct ocfs2_extent_tree *et,
+                                             u32 clusters)
+{
+        struct inode *inode = &cache_info_to_inode(et->et_ci)->vfs_inode;
+
+        ocfs2_extent_map_trunc(inode, clusters);
+}
+
 static int ocfs2_dinode_insert_check(struct ocfs2_extent_tree *et,
                                      struct ocfs2_extent_rec *rec)
 {
@@ -400,6 +418,13 @@ static inline void ocfs2_et_update_clusters(struct ocfs2_extent_tree *et,
         et->et_ops->eo_update_clusters(et, clusters);
 }
 
+static inline void ocfs2_et_extent_map_truncate(struct ocfs2_extent_tree *et,
+                                                u32 clusters)
+{
+        if (et->et_ops->eo_extent_map_truncate)
+                et->et_ops->eo_extent_map_truncate(et, clusters);
+}
+
 static inline int ocfs2_et_root_journal_access(handle_t *handle,
                                                struct ocfs2_extent_tree *et,
                                                int type)
@@ -5106,12 +5131,8 @@ int ocfs2_mark_extent_written(struct inode *inode,
         /*
          * XXX: This should be fixed up so that we just re-insert the
          * next extent records.
-         *
-         * XXX: This is a hack on the extent tree, maybe it should be
-         * an op?
          */
-        if (et->et_ops == &ocfs2_dinode_et_ops)
-                ocfs2_extent_map_trunc(inode, 0);
+        ocfs2_et_extent_map_truncate(et, 0);
 
         left_path = ocfs2_new_path_from_et(et);
         if (!left_path) {
@@ -5393,7 +5414,11 @@ int ocfs2_remove_extent(struct inode *inode,
         struct ocfs2_extent_list *el;
         struct ocfs2_path *path = NULL;
 
-        ocfs2_extent_map_trunc(inode, 0);
+        /*
+         * XXX: Why are we truncating to 0 instead of wherever this
+         * affects us?
+         */
+        ocfs2_et_extent_map_truncate(et, 0);
 
         path = ocfs2_new_path_from_et(et);
         if (!path) {