From 4a9f3a7c336a6b0ffeef2523bef93e67b0921163 Mon Sep 17 00:00:00 2001 From: Roy Franz Date: Sun, 22 Sep 2013 15:45:32 -0700 Subject: [PATCH] efi: Generalize relocate_kernel() for use by other architectures. Rename relocate_kernel() to efi_relocate_kernel(), and take parameters rather than x86 specific structure. Add max_addr argument as for ARM we have some address constraints that we need to enforce when relocating the kernel. Add alloc_size parameter for use by ARM64 which uses an uncompressed kernel, and needs to allocate space for BSS. Signed-off-by: Roy Franz Signed-off-by: Matt Fleming --- arch/x86/boot/compressed/eboot.c | 10 +++- drivers/firmware/efi/efi-stub-helper.c | 76 +++++++++++++++++++------- 2 files changed, 63 insertions(+), 23 deletions(-) diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index 5bbba868e2bc..2e997b6fbdb1 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -733,10 +733,16 @@ struct boot_params *efi_main(void *handle, efi_system_table_t *_table, * address, relocate it. */ if (hdr->pref_address != hdr->code32_start) { - status = relocate_kernel(hdr); - + unsigned long bzimage_addr = hdr->code32_start; + status = efi_relocate_kernel(sys_table, &bzimage_addr, + hdr->init_size, hdr->init_size, + hdr->pref_address, + hdr->kernel_alignment); if (status != EFI_SUCCESS) goto fail; + + hdr->pref_address = hdr->code32_start; + hdr->code32_start = bzimage_addr; } status = exit_boot(boot_params, handle); diff --git a/drivers/firmware/efi/efi-stub-helper.c b/drivers/firmware/efi/efi-stub-helper.c index 333ed9c37751..361e24d8d665 100644 --- a/drivers/firmware/efi/efi-stub-helper.c +++ b/drivers/firmware/efi/efi-stub-helper.c @@ -485,38 +485,72 @@ fail: return status; } - -static efi_status_t relocate_kernel(struct setup_header *hdr) +/* + * Relocate a kernel image, either compressed or uncompressed. + * In the ARM64 case, all kernel images are currently + * uncompressed, and as such when we relocate it we need to + * allocate additional space for the BSS segment. Any low + * memory that this function should avoid needs to be + * unavailable in the EFI memory map, as if the preferred + * address is not available the lowest available address will + * be used. + */ +static efi_status_t efi_relocate_kernel(efi_system_table_t *sys_table_arg, + unsigned long *image_addr, + unsigned long image_size, + unsigned long alloc_size, + unsigned long preferred_addr, + unsigned long alignment) { - unsigned long start, nr_pages; + unsigned long cur_image_addr; + unsigned long new_addr = 0; efi_status_t status; + unsigned long nr_pages; + efi_physical_addr_t efi_addr = preferred_addr; + + if (!image_addr || !image_size || !alloc_size) + return EFI_INVALID_PARAMETER; + if (alloc_size < image_size) + return EFI_INVALID_PARAMETER; + + cur_image_addr = *image_addr; /* * The EFI firmware loader could have placed the kernel image - * anywhere in memory, but the kernel has various restrictions - * on the max physical address it can run at. Attempt to move - * the kernel to boot_params.pref_address, or as low as - * possible. + * anywhere in memory, but the kernel has restrictions on the + * max physical address it can run at. Some architectures + * also have a prefered address, so first try to relocate + * to the preferred address. If that fails, allocate as low + * as possible while respecting the required alignment. */ - start = hdr->pref_address; - nr_pages = round_up(hdr->init_size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE; - - status = efi_call_phys4(sys_table->boottime->allocate_pages, + nr_pages = round_up(alloc_size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE; + status = efi_call_phys4(sys_table_arg->boottime->allocate_pages, EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA, - nr_pages, &start); + nr_pages, &efi_addr); + new_addr = efi_addr; + /* + * If preferred address allocation failed allocate as low as + * possible. + */ if (status != EFI_SUCCESS) { - status = efi_low_alloc(sys_table, hdr->init_size, - hdr->kernel_alignment, &start); - if (status != EFI_SUCCESS) - efi_printk(sys_table, "Failed to alloc mem for kernel\n"); + status = efi_low_alloc(sys_table_arg, alloc_size, alignment, + &new_addr); + } + if (status != EFI_SUCCESS) { + efi_printk(sys_table_arg, "ERROR: Failed to allocate usable memory for kernel.\n"); + return status; } - if (status == EFI_SUCCESS) - memcpy((void *)start, (void *)(unsigned long)hdr->code32_start, - hdr->init_size); + /* + * We know source/dest won't overlap since both memory ranges + * have been allocated by UEFI, so we can safely use memcpy. + */ + memcpy((void *)new_addr, (void *)cur_image_addr, image_size); + /* Zero any extra space we may have allocated for BSS. */ + memset((void *)(new_addr + image_size), alloc_size - image_size, 0); - hdr->pref_address = hdr->code32_start; - hdr->code32_start = (__u32)start; + /* Return the new address of the relocated image. */ + *image_addr = new_addr; return status; } -- 2.39.5