1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */ 2*4882a593Smuzhiyun /* 3*4882a593Smuzhiyun * S390 version 4*4882a593Smuzhiyun * 5*4882a593Smuzhiyun * Derived from "include/asm-i386/usr.h" 6*4882a593Smuzhiyun */ 7*4882a593Smuzhiyun 8*4882a593Smuzhiyun #ifndef _S390_USER_H 9*4882a593Smuzhiyun #define _S390_USER_H 10*4882a593Smuzhiyun 11*4882a593Smuzhiyun #include <asm/page.h> 12*4882a593Smuzhiyun #include <asm/ptrace.h> 13*4882a593Smuzhiyun /* Core file format: The core file is written in such a way that gdb 14*4882a593Smuzhiyun can understand it and provide useful information to the user (under 15*4882a593Smuzhiyun linux we use the 'trad-core' bfd). There are quite a number of 16*4882a593Smuzhiyun obstacles to being able to view the contents of the floating point 17*4882a593Smuzhiyun registers, and until these are solved you will not be able to view the 18*4882a593Smuzhiyun contents of them. Actually, you can read in the core file and look at 19*4882a593Smuzhiyun the contents of the user struct to find out what the floating point 20*4882a593Smuzhiyun registers contain. 21*4882a593Smuzhiyun The actual file contents are as follows: 22*4882a593Smuzhiyun UPAGE: 1 page consisting of a user struct that tells gdb what is present 23*4882a593Smuzhiyun in the file. Directly after this is a copy of the task_struct, which 24*4882a593Smuzhiyun is currently not used by gdb, but it may come in useful at some point. 25*4882a593Smuzhiyun All of the registers are stored as part of the upage. The upage should 26*4882a593Smuzhiyun always be only one page. 27*4882a593Smuzhiyun DATA: The data area is stored. We use current->end_text to 28*4882a593Smuzhiyun current->brk to pick up all of the user variables, plus any memory 29*4882a593Smuzhiyun that may have been malloced. No attempt is made to determine if a page 30*4882a593Smuzhiyun is demand-zero or if a page is totally unused, we just cover the entire 31*4882a593Smuzhiyun range. All of the addresses are rounded in such a way that an integral 32*4882a593Smuzhiyun number of pages is written. 33*4882a593Smuzhiyun STACK: We need the stack information in order to get a meaningful 34*4882a593Smuzhiyun backtrace. We need to write the data from (esp) to 35*4882a593Smuzhiyun current->start_stack, so we round each of these off in order to be able 36*4882a593Smuzhiyun to write an integer number of pages. 37*4882a593Smuzhiyun The minimum core file size is 3 pages, or 12288 bytes. 38*4882a593Smuzhiyun */ 39*4882a593Smuzhiyun 40*4882a593Smuzhiyun 41*4882a593Smuzhiyun /* 42*4882a593Smuzhiyun * This is the old layout of "struct pt_regs", and 43*4882a593Smuzhiyun * is still the layout used by user mode (the new 44*4882a593Smuzhiyun * pt_regs doesn't have all registers as the kernel 45*4882a593Smuzhiyun * doesn't use the extra segment registers) 46*4882a593Smuzhiyun */ 47*4882a593Smuzhiyun 48*4882a593Smuzhiyun /* When the kernel dumps core, it starts by dumping the user struct - 49*4882a593Smuzhiyun this will be used by gdb to figure out where the data and stack segments 50*4882a593Smuzhiyun are within the file, and what virtual addresses to use. */ 51*4882a593Smuzhiyun struct user { 52*4882a593Smuzhiyun /* We start with the registers, to mimic the way that "memory" is returned 53*4882a593Smuzhiyun from the ptrace(3,...) function. */ 54*4882a593Smuzhiyun struct user_regs_struct regs; /* Where the registers are actually stored */ 55*4882a593Smuzhiyun /* The rest of this junk is to help gdb figure out what goes where */ 56*4882a593Smuzhiyun unsigned long int u_tsize; /* Text segment size (pages). */ 57*4882a593Smuzhiyun unsigned long int u_dsize; /* Data segment size (pages). */ 58*4882a593Smuzhiyun unsigned long int u_ssize; /* Stack segment size (pages). */ 59*4882a593Smuzhiyun unsigned long start_code; /* Starting virtual address of text. */ 60*4882a593Smuzhiyun unsigned long start_stack; /* Starting virtual address of stack area. 61*4882a593Smuzhiyun This is actually the bottom of the stack, 62*4882a593Smuzhiyun the top of the stack is always found in the 63*4882a593Smuzhiyun esp register. */ 64*4882a593Smuzhiyun long int signal; /* Signal that caused the core dump. */ 65*4882a593Smuzhiyun unsigned long u_ar0; /* Used by gdb to help find the values for */ 66*4882a593Smuzhiyun /* the registers. */ 67*4882a593Smuzhiyun unsigned long magic; /* To uniquely identify a core file */ 68*4882a593Smuzhiyun char u_comm[32]; /* User command that was responsible */ 69*4882a593Smuzhiyun }; 70*4882a593Smuzhiyun #define NBPG PAGE_SIZE 71*4882a593Smuzhiyun #define UPAGES 1 72*4882a593Smuzhiyun #define HOST_TEXT_START_ADDR (u.start_code) 73*4882a593Smuzhiyun #define HOST_STACK_END_ADDR (u.start_stack + u.u_ssize * NBPG) 74*4882a593Smuzhiyun 75*4882a593Smuzhiyun #endif /* _S390_USER_H */ 76