efi_loader: allocate configuration table array

The system table contains a link to the list of configurations tables.
These include the device tree, SMBIOS table, and the ACPI table.

This array is currently statically linked. With the patch it is allocated
as EFI_RUNTIME_SERVICES_DATA. Due to the structure of the system table we
cannot work with a linked list here.
Signed-off-by: NHeinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: NBin Meng <bmeng.cn@gmail.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

include/efi_loader.h

@@ -17,6 +17,9 @@
 
 #include <linux/list.h>
 
+/* Maximum number of configuration tables */
+#define EFI_MAX_CONFIGURATION_TABLES 16
+
 int __efi_entry_check(void);
 int __efi_exit_check(void);
 const char *__efi_nesting(void);

lib/efi_loader/efi_boottime.c

@@ -35,16 +35,6 @@ LIST_HEAD(efi_events);
  */
 static bool efi_is_direct_boot = true;
 
-/*
- * EFI can pass arbitrary additional "tables" containing vendor specific
- * information to the payload. One such table is the FDT table which contains
- * a pointer to a flattened device tree blob.
- *
- * In most cases we want to pass an FDT to the payload, so reserve one slot of
- * config table space for it. The pointer gets populated by do_bootefi_exec().
- */
-static struct efi_configuration_table __efi_runtime_data efi_conf_table[16];
-
 #ifdef CONFIG_ARM
 /*
  * The "gd" pointer lives in a register on ARM and AArch64 that we declare
@@ -1402,9 +1392,9 @@ static efi_status_t EFIAPI efi_locate_handle_ext(
  */
 static void efi_remove_configuration_table(int i)
 {
-	struct efi_configuration_table *this = &efi_conf_table[i];
-	struct efi_configuration_table *next = &efi_conf_table[i + 1];
-	struct efi_configuration_table *end = &efi_conf_table[systab.nr_tables];
+	struct efi_configuration_table *this = &systab.tables[i];
+	struct efi_configuration_table *next = &systab.tables[i + 1];
+	struct efi_configuration_table *end = &systab.tables[systab.nr_tables];
 
 	memmove(this, next, (ulong)end - (ulong)next);
 	systab.nr_tables--;
@@ -1432,9 +1422,9 @@ efi_status_t efi_install_configuration_table(const efi_guid_t *guid,
 
 	/* Check for guid override */
 	for (i = 0; i < systab.nr_tables; i++) {
-		if (!guidcmp(guid, &efi_conf_table[i].guid)) {
+		if (!guidcmp(guid, &systab.tables[i].guid)) {
 			if (table)
-				efi_conf_table[i].table = table;
+				systab.tables[i].table = table;
 			else
 				efi_remove_configuration_table(i);
 			goto out;
@@ -1445,12 +1435,12 @@ efi_status_t efi_install_configuration_table(const efi_guid_t *guid,
 		return EFI_NOT_FOUND;
 
 	/* No override, check for overflow */
-	if (i >= ARRAY_SIZE(efi_conf_table))
+	if (i >= EFI_MAX_CONFIGURATION_TABLES)
 		return EFI_OUT_OF_RESOURCES;
 
 	/* Add a new entry */
-	memcpy(&efi_conf_table[i].guid, guid, sizeof(*guid));
-	efi_conf_table[i].table = table;
+	memcpy(&systab.tables[i].guid, guid, sizeof(*guid));
+	systab.tables[i].table = table;
 	systab.nr_tables = i + 1;
 
 out:
@@ -3136,7 +3126,7 @@ struct efi_system_table __efi_runtime_data systab = {
 	.runtime = (void *)&efi_runtime_services,
 	.boottime = (void *)&efi_boot_services,
 	.nr_tables = 0,
-	.tables = (void *)efi_conf_table,
+	.tables = NULL,
 };
 
 /**
@@ -3146,9 +3136,18 @@ struct efi_system_table __efi_runtime_data systab = {
  */
 efi_status_t efi_initialize_system_table(void)
 {
+	efi_status_t ret;
+
+	/* Allocate configuration table array */
+	ret = efi_allocate_pool(EFI_RUNTIME_SERVICES_DATA,
+				EFI_MAX_CONFIGURATION_TABLES *
+				sizeof(struct efi_configuration_table),
+				(void **)&systab.tables);
+
 	/* Set crc32 field in table headers */
 	efi_update_table_header_crc32(&systab.hdr);
 	efi_update_table_header_crc32(&efi_runtime_services.hdr);
 	efi_update_table_header_crc32(&efi_boot_services.hdr);
-	return EFI_SUCCESS;
+
+	return ret;
 }