u-boot/lib/efi_loader/efi_dt_fixup.c
Mark Kettenis 073e5db672 efi_loader: fix memory type for memory reservation block
The (yet unreleased version of the) devicetree specification clearly
states that:

  As with the /reserved-memory node, when booting via UEFI
  entries in the Memory Reservation Block must also be listed
  in the system memory map obtained via the GetMemoryMap() toi
  protect against allocations by UEFI applications. The memory
  reservation block entries should be listed with type
  EfiReservedMemoryType.

This restores the behaviour that was changed by commit 4cbb2930bd
("efi_loader: consider no-map property of reserved memory").

Fixes: 4cbb2930bd ("efi_loader: consider no-map property of reserved memory")
Signed-off-by: Mark Kettenis <kettenis@openbsd.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2021-03-25 20:07:18 +01:00

168 lines
4.2 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* EFI_DT_FIXUP_PROTOCOL
*
* Copyright (c) 2020 Heinrich Schuchardt
*/
#include <common.h>
#include <efi_dt_fixup.h>
#include <efi_loader.h>
#include <fdtdec.h>
#include <mapmem.h>
const efi_guid_t efi_guid_dt_fixup_protocol = EFI_DT_FIXUP_PROTOCOL_GUID;
/**
* efi_reserve_memory() - add reserved memory to memory map
*
* @addr: start address of the reserved memory range
* @size: size of the reserved memory range
* @nomap: indicates that the memory range shall not be accessed by the
* UEFI payload
*/
static void efi_reserve_memory(u64 addr, u64 size, bool nomap)
{
int type;
efi_uintn_t ret;
/* Convert from sandbox address space. */
addr = (uintptr_t)map_sysmem(addr, 0);
if (nomap)
type = EFI_RESERVED_MEMORY_TYPE;
else
type = EFI_BOOT_SERVICES_DATA;
ret = efi_add_memory_map(addr, size, type);
if (ret != EFI_SUCCESS)
log_err("Reserved memory mapping failed addr %llx size %llx\n",
addr, size);
}
/**
* efi_carve_out_dt_rsv() - Carve out DT reserved memory ranges
*
* The mem_rsv entries of the FDT are added to the memory map. Any failures are
* ignored because this is not critical and we would rather continue to try to
* boot.
*
* @fdt: Pointer to device tree
*/
void efi_carve_out_dt_rsv(void *fdt)
{
int nr_rsv, i;
u64 addr, size;
int nodeoffset, subnode;
nr_rsv = fdt_num_mem_rsv(fdt);
/* Look for an existing entry and add it to the efi mem map. */
for (i = 0; i < nr_rsv; i++) {
if (fdt_get_mem_rsv(fdt, i, &addr, &size) != 0)
continue;
efi_reserve_memory(addr, size, true);
}
/* process reserved-memory */
nodeoffset = fdt_subnode_offset(fdt, 0, "reserved-memory");
if (nodeoffset >= 0) {
subnode = fdt_first_subnode(fdt, nodeoffset);
while (subnode >= 0) {
fdt_addr_t fdt_addr;
fdt_size_t fdt_size;
/* check if this subnode has a reg property */
fdt_addr = fdtdec_get_addr_size_auto_parent(
fdt, nodeoffset, subnode,
"reg", 0, &fdt_size, false);
/*
* The /reserved-memory node may have children with
* a size instead of a reg property.
*/
if (fdt_addr != FDT_ADDR_T_NONE &&
fdtdec_get_is_enabled(fdt, subnode)) {
bool nomap;
nomap = !!fdt_getprop(fdt, subnode, "no-map",
NULL);
efi_reserve_memory(fdt_addr, fdt_size, nomap);
}
subnode = fdt_next_subnode(fdt, subnode);
}
}
}
/**
* efi_dt_fixup() - fix up device tree
*
* This function implements the Fixup() service of the
* EFI Device Tree Fixup Protocol.
*
* @this: instance of the protocol
* @dtb: device tree provided by caller
* @buffer_size: size of buffer for the device tree including free space
* @flags: bit field designating action to be performed
* Return: status code
*/
static efi_status_t __maybe_unused EFIAPI
efi_dt_fixup(struct efi_dt_fixup_protocol *this, void *dtb,
efi_uintn_t *buffer_size, u32 flags)
{
efi_status_t ret;
size_t required_size;
size_t total_size;
bootm_headers_t img = { 0 };
EFI_ENTRY("%p, %p, %p, %d", this, dtb, buffer_size, flags);
if (this != &efi_dt_fixup_prot || !dtb || !buffer_size ||
!flags || (flags & ~EFI_DT_ALL)) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
if (fdt_check_header(dtb)) {
ret = EFI_INVALID_PARAMETER;
goto out;
}
if (flags & EFI_DT_APPLY_FIXUPS) {
/* Check size */
required_size = fdt_off_dt_strings(dtb) +
fdt_size_dt_strings(dtb) +
0x3000;
total_size = fdt_totalsize(dtb);
if (required_size < total_size)
required_size = total_size;
if (required_size > *buffer_size) {
*buffer_size = required_size;
ret = EFI_BUFFER_TOO_SMALL;
goto out;
}
fdt_set_totalsize(dtb, *buffer_size);
if (image_setup_libfdt(&img, dtb, 0, NULL)) {
log_err("failed to process device tree\n");
ret = EFI_INVALID_PARAMETER;
goto out;
}
}
if (flags & EFI_DT_RESERVE_MEMORY)
efi_carve_out_dt_rsv(dtb);
if (flags & EFI_DT_INSTALL_TABLE) {
ret = efi_install_configuration_table(&efi_guid_fdt, dtb);
if (ret != EFI_SUCCESS) {
log_err("failed to install device tree\n");
goto out;
}
}
ret = EFI_SUCCESS;
out:
return EFI_EXIT(ret);
}
struct efi_dt_fixup_protocol efi_dt_fixup_prot = {
.revision = EFI_DT_FIXUP_PROTOCOL_REVISION,
.fixup = efi_dt_fixup
};