// SPDX-License-Identifier: GPL-2.0 /* Copyright(c) 2019 Intel Corporation. All rights reserved. */ #include <linux/efi.h> #include <asm/e820/api.h> #include "fake_mem.h" void __init efi_fake_memmap_early(void) { int i; /* * The late efi_fake_mem() call can handle all requests if * EFI_MEMORY_SP support is disabled. */ if (!efi_soft_reserve_enabled()) return; if (!efi_enabled(EFI_MEMMAP) || !nr_fake_mem) return; /* * Given that efi_fake_memmap() needs to perform memblock * allocations it needs to run after e820__memblock_setup(). * However, if efi_fake_mem specifies EFI_MEMORY_SP for a given * address range that potentially needs to mark the memory as * reserved prior to e820__memblock_setup(). Update e820 * directly if EFI_MEMORY_SP is specified for an * EFI_CONVENTIONAL_MEMORY descriptor. */ for (i = 0; i < nr_fake_mem; i++) { struct efi_mem_range *mem = &efi_fake_mems[i]; efi_memory_desc_t *md; u64 m_start, m_end; if ((mem->attribute & EFI_MEMORY_SP) == 0) continue; m_start = mem->range.start; m_end = mem->range.end; for_each_efi_memory_desc(md) { u64 start, end, size; if (md->type != EFI_CONVENTIONAL_MEMORY) continue; start = md->phys_addr; end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1; if (m_start <= end && m_end >= start) /* fake range overlaps descriptor */; else continue; /* * Trim the boundary of the e820 update to the * descriptor in case the fake range overlaps * !EFI_CONVENTIONAL_MEMORY */ start = max(start, m_start); end = min(end, m_end); size = end - start + 1; if (end <= start) continue; /* * Ensure each efi_fake_mem instance results in * a unique e820 resource */ e820__range_remove(start, size, E820_TYPE_RAM, 1); e820__range_add(start, size, E820_TYPE_SOFT_RESERVED); e820__update_table(e820_table); } } }