resources: add interfaces that return conflict information

request_resource() and insert_resource() only return success or failure,
which no information about what existing resource conflicted with the
proposed new reservation.  This patch adds request_resource_conflict()
and insert_resource_conflict(), which return the conflicting resource.

Callers may use this for better error messages or to adjust the new
resource and retry the request.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 71ab79da7e7f..26fad187d661 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -112,12 +112,14 @@ struct resource_list {
 extern struct resource ioport_resource;
 extern struct resource iomem_resource;
 
+extern struct resource *request_resource_conflict(struct resource *root, struct resource *new);
 extern int request_resource(struct resource *root, struct resource *new);
 extern int release_resource(struct resource *new);
 void release_child_resources(struct resource *new);
 extern void reserve_region_with_split(struct resource *root,
                              resource_size_t start, resource_size_t end,
                              const char *name);
+extern struct resource *insert_resource_conflict(struct resource *parent, struct resource *new);
 extern int insert_resource(struct resource *parent, struct resource *new);
 extern void insert_resource_expand_to_fit(struct resource *root, struct resource *new);
 extern int allocate_resource(struct resource *root, struct resource *new,