efi_loader: clean up runtime detaching
The detaching of the runtime will have to move to ExitBootServices() to
encompass operating system that do not call SetVirtualAddressMap().
This patch changes the logic for the relocation of the pointers in the
runtime table such that the relocation becomes independent of the entries
in the detach list.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/lib/efi_loader/efi_runtime.c b/lib/efi_loader/efi_runtime.c
index c56230c..702136a 100644
--- a/lib/efi_loader/efi_runtime.c
+++ b/lib/efi_loader/efi_runtime.c
@@ -420,29 +420,53 @@
}
};
-static bool efi_runtime_tobedetached(void *p)
+/**
+ * efi_is_runtime_service_pointer() - check if pointer points to runtime table
+ *
+ * @p: pointer to check
+ * Return: true if the pointer points to a service function pointer in the
+ * runtime table
+ */
+static bool efi_is_runtime_service_pointer(void *p)
{
- int i;
-
- for (i = 0; i < ARRAY_SIZE(efi_runtime_detach_list); i++)
- if (efi_runtime_detach_list[i].ptr == p)
- return true;
-
- return false;
+ return p >= (void *)&efi_runtime_services.get_time &&
+ p <= (void *)&efi_runtime_services.query_variable_info;
}
-static void efi_runtime_detach(ulong offset)
+static __efi_runtime void efi_runtime_detach(void)
{
int i;
- ulong patchoff = offset - (ulong)gd->relocaddr;
+ /*
+ * Replace boottime functions by runtime functions
+ * TODO: move this step to ExitBootServices()
+ */
for (i = 0; i < ARRAY_SIZE(efi_runtime_detach_list); i++) {
ulong patchto = (ulong)efi_runtime_detach_list[i].patchto;
ulong *p = efi_runtime_detach_list[i].ptr;
- ulong newaddr = patchto ? (patchto + patchoff) : 0;
- debug("%s: Setting %p to %lx\n", __func__, p, newaddr);
- *p = newaddr;
+ debug("%s: Setting %p to %lx\n", __func__, p, patchto);
+ *p = patchto;
+ }
+}
+
+static __efi_runtime void efi_relocate_runtime_table(ulong offset)
+{
+ ulong patchoff;
+ void **pos;
+
+ /* Relocate the runtime services pointers */
+ patchoff = offset - gd->relocaddr;
+ for (pos = (void **)&efi_runtime_services.get_time;
+ pos <= (void **)&efi_runtime_services.query_variable_info; ++pos) {
+ /*
+ * The UEFI spec requires not to update VirtualAddressMap()
+ * and ConvertPointer().
+ */
+ if (*pos && pos !=
+ (void **)&efi_runtime_services.set_virtual_address_map &&
+ pos != (void **)&efi_runtime_services.convert_pointer)
+ *pos += patchoff;
}
/* Update CRC32 */
@@ -467,6 +491,10 @@
p = (void*)((ulong)rel->offset - base) + gd->relocaddr;
+ /* The runtime services are updated in efi_runtime_detach() */
+ if (map && efi_is_runtime_service_pointer(p))
+ continue;
+
debug("%s: rel->info=%#lx *p=%#lx rel->offset=%p\n", __func__,
rel->info, *p, rel->offset);
@@ -490,9 +518,8 @@
}
#endif
default:
- if (!efi_runtime_tobedetached(p))
- printf("%s: Unknown relocation type %llx\n",
- __func__, rel->info & R_MASK);
+ printf("%s: Unknown relocation type %llx\n",
+ __func__, rel->info & R_MASK);
continue;
}
@@ -500,9 +527,8 @@
if (map && ((newaddr < map->virtual_start) ||
newaddr > (map->virtual_start +
(map->num_pages << EFI_PAGE_SHIFT)))) {
- if (!efi_runtime_tobedetached(p))
- printf("%s: Relocation at %p is out of "
- "range (%lx)\n", __func__, p, newaddr);
+ printf("%s: Relocation at %p is out of range (%lx)\n",
+ __func__, p, newaddr);
continue;
}
@@ -607,7 +633,15 @@
}
}
- /* Move the actual runtime code over */
+ /*
+ * Some runtime services are implemented in a way that we can only offer
+ * them at boottime. Replace those function pointers.
+ *
+ * TODO: move this call to ExitBootServices().
+ */
+ efi_runtime_detach();
+
+ /* Relocate the runtime. See TODO above */
for (i = 0; i < n; i++) {
struct efi_mem_desc *map;
@@ -616,10 +650,8 @@
ulong new_offset = map->virtual_start -
map->physical_start + gd->relocaddr;
+ efi_relocate_runtime_table(new_offset);
efi_runtime_relocate(new_offset, map);
- /* Once we're virtual, we can no longer handle
- complex callbacks */
- efi_runtime_detach(new_offset);
return EFI_EXIT(EFI_SUCCESS);
}
}