root/arch/powerpc/include/asm/user.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_POWERPC_USER_H
#define _ASM_POWERPC_USER_H

#include <asm/ptrace.h>
#include <asm/page.h>

/*
 * Adapted from <asm-alpha/user.h>
 *
 * Core file format: The core file is written in such a way that gdb
 * can understand it and provide useful information to the user (under
 * linux we use the `trad-core' bfd, NOT the osf-core).  The file contents
 * are as follows:
 *
 *  upage: 1 page consisting of a user struct that tells gdb
 *      what is present in the file.  Directly after this is a
 *      copy of the task_struct, which is currently not used by gdb,
 *      but it may come in handy at some point.  All of the registers
 *      are stored as part of the upage.  The upage should always be
 *      only one page long.
 *  data: The data segment follows next.  We use current->end_text to
 *      current->brk to pick up all of the user variables, plus any memory
 *      that may have been sbrk'ed.  No attempt is made to determine if a
 *      page is demand-zero or if a page is totally unused, we just cover
 *      the entire range.  All of the addresses are rounded in such a way
 *      that an integral number of pages is written.
 *  stack: We need the stack information in order to get a meaningful
 *      backtrace.  We need to write the data from usp to
 *      current->start_stack, so we round each of these in order to be able
 *      to write an integer number of pages.
 */
struct user {
        struct user_pt_regs regs;               /* entire machine state */
        size_t          u_tsize;                /* text size (pages) */
        size_t          u_dsize;                /* data size (pages) */
        size_t          u_ssize;                /* stack size (pages) */
        unsigned long   start_code;             /* text starting address */
        unsigned long   start_data;             /* data starting address */
        unsigned long   start_stack;            /* stack starting address */
        long int        signal;                 /* signal causing core dump */
        unsigned long   u_ar0;                  /* help gdb find registers */
        unsigned long   magic;                  /* identifies a core file */
        char            u_comm[32];             /* user command name */
};

#endif  /* _ASM_POWERPC_USER_H */