efi_loader: implement OpenProtocolInformation

efi_open_protocol_information provides the agent and controller
handles as well as the attributes and open count of an protocol
on a handle.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
[agraf: fix counting error]
Signed-off-by: Alexander Graf <agraf@suse.de>

diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
index f8cc3180743f7026ae2e21acfe53c17dee833e52..7a6c282f818a8dff27469fd23dc1c4a9b9e29259 100644 (file)
--- a/lib/efi_loader/efi_boottime.c
+++ b/lib/efi_loader/efi_boottime.c
@@ -1742,9 +1742,49 @@ static efi_status_t EFIAPI efi_open_protocol_information(efi_handle_t handle,
                        struct efi_open_protocol_info_entry **entry_buffer,
                        efi_uintn_t *entry_count)
 {
+       unsigned long buffer_size;
+       unsigned long count;
+       struct efi_handler *handler;
+       struct efi_open_protocol_info_item *item;
+       efi_status_t r;
+
        EFI_ENTRY("%p, %pUl, %p, %p", handle, protocol, entry_buffer,
                  entry_count);
-       return EFI_EXIT(EFI_NOT_FOUND);
+
+       /* Check parameters */
+       if (!entry_buffer) {
+               r = EFI_INVALID_PARAMETER;
+               goto out;
+       }
+       r = efi_search_protocol(handle, protocol, &handler);
+       if (r != EFI_SUCCESS)
+               goto out;
+
+       /* Count entries */
+       count = 0;
+       list_for_each_entry(item, &handler->open_infos, link) {
+               if (item->info.open_count)
+                       ++count;
+       }
+       *entry_count = count;
+       *entry_buffer = NULL;
+       if (!count) {
+               r = EFI_SUCCESS;
+               goto out;
+       }
+
+       /* Copy entries */
+       buffer_size = count * sizeof(struct efi_open_protocol_info_entry);
+       r = efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES, buffer_size,
+                             (void **)entry_buffer);
+       if (r != EFI_SUCCESS)
+               goto out;
+       list_for_each_entry_reverse(item, &handler->open_infos, link) {
+               if (item->info.open_count)
+                       (*entry_buffer)[--count] = item->info;
+       }
+out:
+       return EFI_EXIT(r);
 }
 
 /*