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 <roy.franz@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
This commit is contained in:
Roy Franz 2013-09-22 15:45:32 -07:00 committed by Matt Fleming
parent c6866d7238
commit 4a9f3a7c33
2 changed files with 63 additions and 23 deletions

View File

@ -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);

View File

@ -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
* 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.
*/
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, &efi_addr);
new_addr = efi_addr;
/*
* If preferred address allocation failed allocate as low as
* possible.
*/
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,
EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
nr_pages, &start);
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;
}