[PATCH v5 3/8] efi: split off remapping code from efi_config_init()

Ard Biesheuvel
2015-01-08T18:48:29Z

Split of the remapping code from efi_config_init() so that the caller
can perform its own remapping. This is necessary to correctly handle
virtually remapped UEFI memory regions under kexec, as efi.systab will
have been updated to a virtual address.

Acked-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
drivers/firmware/efi/efi.c | 56 ++++++++++++++++++++++++++--------------------
include/linux/efi.h | 2 ++
2 files changed, 34 insertions(+), 24 deletions(-)

diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 9035c1b74d58..b7ba9d8ec4b0 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -293,29 +293,15 @@ static __init int match_config_table(efi_guid_t *guid,
return 0;
}

-int __init efi_config_init(efi_config_table_type_t *arch_tables)
+int __init efi_config_parse_tables(void *config_tables, int count, int sz,
+ efi_config_table_type_t *arch_tables)
{
- void *config_tables, *tablep;
- int i, sz;
-
- if (efi_enabled(EFI_64BIT))
- sz = sizeof(efi_config_table_64_t);
- else
- sz = sizeof(efi_config_table_32_t);
-
- /*
- * Let's see what config tables the firmware passed to us.
- */
- config_tables = early_memremap(efi.systab->tables,
- efi.systab->nr_tables * sz);
- if (config_tables == NULL) {
- pr_err("Could not map Configuration table!\n");
- return -ENOMEM;
- }
+ void *tablep;
+ int i;

tablep = config_tables;
pr_info("");
- for (i = 0; i < efi.systab->nr_tables; i++) {
+ for (i = 0; i < count; i++) {
efi_guid_t guid;
unsigned long table;

@@ -328,8 +314,6 @@ int __init efi_config_init(efi_config_table_type_t *arch_tables)
if (table64 >> 32) {
pr_cont("\n");
pr_err("Table located above 4GB, disabling EFI.\n");
- early_memunmap(config_tables,
- efi.systab->nr_tables * sz);
return -EINVAL;
}
#endif
@@ -344,13 +328,37 @@ int __init efi_config_init(efi_config_table_type_t *arch_tables)
tablep += sz;
}
pr_cont("\n");
- early_memunmap(config_tables, efi.systab->nr_tables * sz);
-
set_bit(EFI_CONFIG_TABLES, &efi.flags);
-
return 0;
}

+int __init efi_config_init(efi_config_table_type_t *arch_tables)
+{
+ void *config_tables;
+ int sz, ret;
+
+ if (efi_enabled(EFI_64BIT))
+ sz = sizeof(efi_config_table_64_t);
+ else
+ sz = sizeof(efi_config_table_32_t);
+
+ /*
+ * Let's see what config tables the firmware passed to us.
+ */
+ config_tables = early_memremap(efi.systab->tables,
+ efi.systab->nr_tables * sz);
+ if (config_tables == NULL) {
+ pr_err("Could not map Configuration table!\n");
+ return -ENOMEM;
+ }
+
+ ret = efi_config_parse_tables(config_tables, efi.systab->nr_tables, sz,
+ arch_tables);
+
+ early_memunmap(config_tables, efi.systab->nr_tables * sz);
+ return ret;
+}
+
#ifdef CONFIG_EFI_VARS_MODULE
static int __init efi_load_efivars(void)
{
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 0238d612750e..5ffe5115951f 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -875,6 +875,8 @@ static inline efi_status_t efi_query_variable_store(u32 attributes, unsigned lon
#endif
extern void __iomem *efi_lookup_mapped_addr(u64 phys_addr);
extern int efi_config_init(efi_config_table_type_t *arch_tables);
+extern int efi_config_parse_tables(void *config_tables, int count, int sz,
+ efi_config_table_type_t *arch_tables);
extern u64 efi_get_iobase (void);
extern u32 efi_mem_type (unsigned long phys_addr);
extern u64 efi_mem_attributes (unsigned long phys_addr);
--
1.8.3.2