Expose the EFI boot time memory map to the kernel via a configuration
table. This is arch agnostic and enables future changes that remove the
dependency on DT on architectures that don't otherwise rely on it.
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
---
drivers/firmware/efi/libstub/arm64-stub.c | 2 +-
drivers/firmware/efi/libstub/efi-stub-helper.c | 2 +-
drivers/firmware/efi/libstub/efistub.h | 3 ++-
drivers/firmware/efi/libstub/mem.c | 26 ++++++++++++++++++--
drivers/firmware/efi/libstub/randomalloc.c | 2 +-
drivers/firmware/efi/libstub/relocate.c | 2 +-
include/linux/efi.h | 1 +
7 files changed, 31 insertions(+), 7 deletions(-)
diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c
index e9d516ad5f97..df05c53baa23 100644
--- a/drivers/firmware/efi/libstub/arm64-stub.c
+++ b/drivers/firmware/efi/libstub/arm64-stub.c
@@ -55,7 +55,7 @@ static bool check_image_region(u64 base, u64 size)
bool ret = false;
int map_offset;
- status = efi_get_memory_map(&map);
+ status = efi_get_memory_map(&map, false);
if (status != EFI_SUCCESS)
return false;
diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index 742ecd9e0df3..f1f7a823be17 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -438,7 +438,7 @@ efi_status_t efi_exit_boot_services(void *handle, void *priv,
struct efi_boot_memmap *map;
efi_status_t status;
- status = efi_get_memory_map(&map);
+ status = efi_get_memory_map(&map, true);
if (status != EFI_SUCCESS)
goto fail;
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index f65a8a3844b8..b4fb6d4e8a59 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -897,7 +897,8 @@ void efi_apply_loadoptions_quirk(const void **load_options, u32 *load_options_si
char *efi_convert_cmdline(efi_loaded_image_t *image, int *cmd_line_len);
-efi_status_t efi_get_memory_map(struct efi_boot_memmap **map);
+efi_status_t efi_get_memory_map(struct efi_boot_memmap **map,
+ bool install_cfg_tbl);
efi_status_t efi_allocate_pages(unsigned long size, unsigned long *addr,
unsigned long max);
diff --git a/drivers/firmware/efi/libstub/mem.c b/drivers/firmware/efi/libstub/mem.c
index 40721573e494..ed4c145afe11 100644
--- a/drivers/firmware/efi/libstub/mem.c
+++ b/drivers/firmware/efi/libstub/mem.c
@@ -9,14 +9,20 @@
* efi_get_memory_map() - get memory map
* @map: pointer to memory map pointer to which to assign the
* newly allocated memory map
+ * @install_cfg_tbl: whether or not to install the boot memory map as a
+ * configuration table
*
* Retrieve the UEFI memory map. The allocated memory leaves room for
* up to EFI_MMAP_NR_SLACK_SLOTS additional memory map entries.
*
* Return: status code
*/
-efi_status_t efi_get_memory_map(struct efi_boot_memmap **map)
+efi_status_t efi_get_memory_map(struct efi_boot_memmap **map,
+ bool install_cfg_tbl)
{
+ int memtype = install_cfg_tbl ? EFI_ACPI_RECLAIM_MEMORY
+ : EFI_LOADER_DATA;
+ efi_guid_t tbl_guid = LINUX_EFI_BOOT_MEMMAP_GUID;
struct efi_boot_memmap *m, tmp;
efi_status_t status;
unsigned long size;
@@ -28,11 +34,23 @@ efi_status_t efi_get_memory_map(struct efi_boot_memmap **map)
return EFI_LOAD_ERROR;
size = tmp.map_size + tmp.desc_size * EFI_MMAP_NR_SLACK_SLOTS;
- status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, sizeof(*m) + size,
+ status = efi_bs_call(allocate_pool, memtype, sizeof(*m) + size,
(void **)&m);
if (status != EFI_SUCCESS)
return status;
+ if (install_cfg_tbl) {
+ /*
+ * Installing a configuration table might allocate memory, and
+ * this may modify the memory map. This means we should install
+ * the configuration table first, and re-install or delete it
+ * as needed.
+ */
+ status = efi_bs_call(install_configuration_table, &tbl_guid, m);
+ if (status != EFI_SUCCESS)
+ goto free_map;
+ }
+
m->buff_size = m->map_size = size;
status = efi_bs_call(get_memory_map, &m->map_size, m->map, &m->map_key,
&m->desc_size, &m->desc_ver);
@@ -40,6 +58,10 @@ efi_status_t efi_get_memory_map(struct efi_boot_memmap **map)
if (status == EFI_SUCCESS) {
*map = m;
} else {
+ if (install_cfg_tbl)
+ efi_bs_call(install_configuration_table, &tbl_guid,
+ NULL);
+free_map:
efi_bs_call(free_pool, m);
}
diff --git a/drivers/firmware/efi/libstub/randomalloc.c b/drivers/firmware/efi/libstub/randomalloc.c
index 5d6000c717cc..9fb5869896be 100644
--- a/drivers/firmware/efi/libstub/randomalloc.c
+++ b/drivers/firmware/efi/libstub/randomalloc.c
@@ -61,7 +61,7 @@ efi_status_t efi_random_alloc(unsigned long size,
efi_status_t status;
int map_offset;
- status = efi_get_memory_map(&map);
+ status = efi_get_memory_map(&map, false);
if (status != EFI_SUCCESS)
return status;
diff --git a/drivers/firmware/efi/libstub/relocate.c b/drivers/firmware/efi/libstub/relocate.c
index cd80db33ab1e..bf6fbd5d22a1 100644
--- a/drivers/firmware/efi/libstub/relocate.c
+++ b/drivers/firmware/efi/libstub/relocate.c
@@ -28,7 +28,7 @@ efi_status_t efi_low_alloc_above(unsigned long size, unsigned long align,
unsigned long nr_pages;
int i;
- status = efi_get_memory_map(&map);
+ status = efi_get_memory_map(&map, false);
if (status != EFI_SUCCESS)
goto fail;
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 8668d9769bb0..89f16ec3ebab 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -414,6 +414,7 @@ void efi_native_runtime_setup(void);
#define LINUX_EFI_ZBOOT_MEDIA_GUID EFI_GUID(0xe565a30d, 0x47da, 0x4dbd, 0xb3, 0x54, 0x9b, 0xb5, 0xc8, 0x4f, 0x8b, 0xe2)
#define LINUX_EFI_MOK_VARIABLE_TABLE_GUID EFI_GUID(0xc451ed2b, 0x9694, 0x45d3, 0xba, 0xba, 0xed, 0x9f, 0x89, 0x88, 0xa3, 0x89)
#define LINUX_EFI_COCO_SECRET_AREA_GUID EFI_GUID(0xadf956ad, 0xe98c, 0x484c, 0xae, 0x11, 0xb5, 0x1c, 0x7d, 0x33, 0x64, 0x47)
+#define LINUX_EFI_BOOT_MEMMAP_GUID EFI_GUID(0x800f683f, 0xd08b, 0x423a, 0xa2, 0x93, 0x96, 0x5c, 0x3c, 0x6f, 0xe2, 0xb4)
#define RISCV_EFI_BOOT_PROTOCOL_GUID EFI_GUID(0xccd15fec, 0x6f73, 0x4eec, 0x83, 0x95, 0x3e, 0x69, 0xe4, 0xb9, 0x40, 0xbf)
--
2.35.1
