userns: Simplify insert_extent
Consolidate the code to write to the new mapping at the end of the
function to remove the duplication. Move the increase in the number
of mappings into insert_extent, keeping the logic together.
Just a small increase in readability and maintainability.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index 1d02988..899c310 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -758,12 +758,7 @@ static bool mappings_overlap(struct uid_gid_map *new_map,
*/
static int insert_extent(struct uid_gid_map *map, struct uid_gid_extent *extent)
{
- if (map->nr_extents < UID_GID_MAP_MAX_BASE_EXTENTS) {
- map->extent[map->nr_extents].first = extent->first;
- map->extent[map->nr_extents].lower_first = extent->lower_first;
- map->extent[map->nr_extents].count = extent->count;
- return 0;
- }
+ struct uid_gid_extent *dest;
if (map->nr_extents == UID_GID_MAP_MAX_BASE_EXTENTS) {
struct uid_gid_extent *forward;
@@ -784,9 +779,13 @@ static int insert_extent(struct uid_gid_map *map, struct uid_gid_extent *extent)
map->reverse = NULL;
}
- map->forward[map->nr_extents].first = extent->first;
- map->forward[map->nr_extents].lower_first = extent->lower_first;
- map->forward[map->nr_extents].count = extent->count;
+ if (map->nr_extents < UID_GID_MAP_MAX_BASE_EXTENTS)
+ dest = &map->extent[map->nr_extents];
+ else
+ dest = &map->forward[map->nr_extents];
+
+ *dest = *extent;
+ map->nr_extents++;
return 0;
}
@@ -968,8 +967,6 @@ static ssize_t map_write(struct file *file, const char __user *buf,
if (ret < 0)
goto out;
ret = -EINVAL;
-
- new_map.nr_extents++;
}
/* Be very certaint the new map actually exists */
if (new_map.nr_extents == 0)
