55 lines
1.8 KiB
C
55 lines
1.8 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* Copyright (c) 2026, Google LLC.
|
|
* Pasha Tatashin <pasha.tatashin@soleen.com>
|
|
*/
|
|
|
|
/**
|
|
* DOC: KHO Serialization Blocks ABI
|
|
*
|
|
* Subsystems using the KHO Serialization Blocks framework rely on the stable
|
|
* Application Binary Interface defined below to pass serialized state from a
|
|
* pre-update kernel to a post-update kernel.
|
|
*
|
|
* This interface is a contract. Any modification to the structure fields,
|
|
* compatible strings, or the layout of the `__packed` serialization
|
|
* structures defined here constitutes a breaking change. Such changes require
|
|
* incrementing the version number in the `KHO_FDT_COMPATIBLE` string to
|
|
* prevent a new kernel from misinterpreting data from an old kernel.
|
|
*
|
|
* Changes are allowed provided the compatibility version is incremented;
|
|
* however, backward/forward compatibility is only guaranteed for kernels
|
|
* supporting the same ABI version.
|
|
*/
|
|
|
|
#ifndef _LINUX_KHO_ABI_BLOCK_H
|
|
#define _LINUX_KHO_ABI_BLOCK_H
|
|
|
|
#include <asm/page.h>
|
|
#include <linux/types.h>
|
|
|
|
/**
|
|
* KHO_BLOCK_SIZE - The size of each serialization block.
|
|
*
|
|
* This is defined as PAGE_SIZE. PAGE_SIZE is ABI compliant because live
|
|
* update between kernels with different page sizes is not supported by KHO.
|
|
*/
|
|
#define KHO_BLOCK_SIZE PAGE_SIZE
|
|
|
|
/**
|
|
* struct kho_block_header_ser - Header for the serialized data block.
|
|
* @next: Physical address of the next struct kho_block_header_ser.
|
|
* @count: The number of entries that immediately follow this header in the
|
|
* memory block.
|
|
*
|
|
* This structure is located at the beginning of a block of physical memory
|
|
* preserved across a kexec. It provides the necessary metadata to interpret
|
|
* the array of entries that follow.
|
|
*/
|
|
struct kho_block_header_ser {
|
|
u64 next;
|
|
u64 count;
|
|
} __packed;
|
|
|
|
#endif /* _LINUX_KHO_ABI_BLOCK_H */
|