A type punning from (void *) to (u64 *) plus reading its value will cause
bus error on the Linux OS installed on sparc arch, because sparc core will
do a misaligned access and we don't have an option like -misalign or -xmemalign
in gcc.
Instead we introduce a struct to avoid the memory misalignment.
Signed-off-by: Liu Bo <bo.li.liu@xxxxxxxxxx>
---
disk-io.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/disk-io.c b/disk-io.c
index 0af3898..eed7d7e 100644
--- a/disk-io.c
+++ b/disk-io.c
@@ -650,10 +650,14 @@ insert:
return root;
}
+struct root_obj {
+ u64 objectid;
+};
+
static int btrfs_fs_roots_compare_objectids(struct rb_node *node,
void *data)
{
- u64 objectid = *((u64 *)data);
+ u64 objectid = ((struct root_obj *)data)->objectid;
struct btrfs_root *root;
root = rb_entry(node, struct btrfs_root, rb_node);
@@ -669,9 +673,11 @@ static int btrfs_fs_roots_compare_roots(struct rb_node *node1,
struct rb_node *node2)
{
struct btrfs_root *root;
+ struct root_obj obj;
root = rb_entry(node2, struct btrfs_root, rb_node);
- return btrfs_fs_roots_compare_objectids(node1, (void *)&root->objectid);
+ obj.objectid = root->objectid;
+ return btrfs_fs_roots_compare_objectids(node1, (void *)&obj);
}
struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
@@ -680,6 +686,7 @@ struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
struct btrfs_root *root;
struct rb_node *node;
int ret;
+ struct root_obj obj;
if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
return fs_info->tree_root;
@@ -695,7 +702,8 @@ struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
BUG_ON(location->objectid == BTRFS_TREE_RELOC_OBJECTID ||
location->offset != (u64)-1);
- node = rb_search(&fs_info->fs_root_tree, (void *)&location->objectid,
+ obj.objectid = location->objectid;
+ node = rb_search(&fs_info->fs_root_tree, (void *)&obj,
btrfs_fs_roots_compare_objectids, NULL);
if (node)
return container_of(node, struct btrfs_root, rb_node);
--
1.8.1.4
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
