1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */ 2*4882a593Smuzhiyun #ifndef _ARM_USER_H 3*4882a593Smuzhiyun #define _ARM_USER_H 4*4882a593Smuzhiyun 5*4882a593Smuzhiyun #include <asm/page.h> 6*4882a593Smuzhiyun #include <asm/ptrace.h> 7*4882a593Smuzhiyun /* Core file format: The core file is written in such a way that gdb 8*4882a593Smuzhiyun can understand it and provide useful information to the user (under 9*4882a593Smuzhiyun linux we use the 'trad-core' bfd). There are quite a number of 10*4882a593Smuzhiyun obstacles to being able to view the contents of the floating point 11*4882a593Smuzhiyun registers, and until these are solved you will not be able to view the 12*4882a593Smuzhiyun contents of them. Actually, you can read in the core file and look at 13*4882a593Smuzhiyun the contents of the user struct to find out what the floating point 14*4882a593Smuzhiyun registers contain. 15*4882a593Smuzhiyun The actual file contents are as follows: 16*4882a593Smuzhiyun UPAGE: 1 page consisting of a user struct that tells gdb what is present 17*4882a593Smuzhiyun in the file. Directly after this is a copy of the task_struct, which 18*4882a593Smuzhiyun is currently not used by gdb, but it may come in useful at some point. 19*4882a593Smuzhiyun All of the registers are stored as part of the upage. The upage should 20*4882a593Smuzhiyun always be only one page. 21*4882a593Smuzhiyun DATA: The data area is stored. We use current->end_text to 22*4882a593Smuzhiyun current->brk to pick up all of the user variables, plus any memory 23*4882a593Smuzhiyun that may have been malloced. No attempt is made to determine if a page 24*4882a593Smuzhiyun is demand-zero or if a page is totally unused, we just cover the entire 25*4882a593Smuzhiyun range. All of the addresses are rounded in such a way that an integral 26*4882a593Smuzhiyun number of pages is written. 27*4882a593Smuzhiyun STACK: We need the stack information in order to get a meaningful 28*4882a593Smuzhiyun backtrace. We need to write the data from (esp) to 29*4882a593Smuzhiyun current->start_stack, so we round each of these off in order to be able 30*4882a593Smuzhiyun to write an integer number of pages. 31*4882a593Smuzhiyun The minimum core file size is 3 pages, or 12288 bytes. 32*4882a593Smuzhiyun */ 33*4882a593Smuzhiyun 34*4882a593Smuzhiyun struct user_fp { 35*4882a593Smuzhiyun struct fp_reg { 36*4882a593Smuzhiyun unsigned int sign1:1; 37*4882a593Smuzhiyun unsigned int unused:15; 38*4882a593Smuzhiyun unsigned int sign2:1; 39*4882a593Smuzhiyun unsigned int exponent:14; 40*4882a593Smuzhiyun unsigned int j:1; 41*4882a593Smuzhiyun unsigned int mantissa1:31; 42*4882a593Smuzhiyun unsigned int mantissa0:32; 43*4882a593Smuzhiyun } fpregs[8]; 44*4882a593Smuzhiyun unsigned int fpsr:32; 45*4882a593Smuzhiyun unsigned int fpcr:32; 46*4882a593Smuzhiyun unsigned char ftype[8]; 47*4882a593Smuzhiyun unsigned int init_flag; 48*4882a593Smuzhiyun }; 49*4882a593Smuzhiyun 50*4882a593Smuzhiyun /* When the kernel dumps core, it starts by dumping the user struct - 51*4882a593Smuzhiyun this will be used by gdb to figure out where the data and stack segments 52*4882a593Smuzhiyun are within the file, and what virtual addresses to use. */ 53*4882a593Smuzhiyun struct user{ 54*4882a593Smuzhiyun /* We start with the registers, to mimic the way that "memory" is returned 55*4882a593Smuzhiyun from the ptrace(3,...) function. */ 56*4882a593Smuzhiyun struct pt_regs regs; /* Where the registers are actually stored */ 57*4882a593Smuzhiyun /* ptrace does not yet supply these. Someday.... */ 58*4882a593Smuzhiyun int u_fpvalid; /* True if math co-processor being used. */ 59*4882a593Smuzhiyun /* for this mess. Not yet used. */ 60*4882a593Smuzhiyun /* The rest of this junk is to help gdb figure out what goes where */ 61*4882a593Smuzhiyun unsigned long int u_tsize; /* Text segment size (pages). */ 62*4882a593Smuzhiyun unsigned long int u_dsize; /* Data segment size (pages). */ 63*4882a593Smuzhiyun unsigned long int u_ssize; /* Stack segment size (pages). */ 64*4882a593Smuzhiyun unsigned long start_code; /* Starting virtual address of text. */ 65*4882a593Smuzhiyun unsigned long start_stack; /* Starting virtual address of stack area. 66*4882a593Smuzhiyun This is actually the bottom of the stack, 67*4882a593Smuzhiyun the top of the stack is always found in the 68*4882a593Smuzhiyun esp register. */ 69*4882a593Smuzhiyun long int signal; /* Signal that caused the core dump. */ 70*4882a593Smuzhiyun int reserved; /* No longer used */ 71*4882a593Smuzhiyun unsigned long u_ar0; /* Used by gdb to help find the values for */ 72*4882a593Smuzhiyun /* the registers. */ 73*4882a593Smuzhiyun unsigned long magic; /* To uniquely identify a core file */ 74*4882a593Smuzhiyun char u_comm[32]; /* User command that was responsible */ 75*4882a593Smuzhiyun int u_debugreg[8]; /* No longer used */ 76*4882a593Smuzhiyun struct user_fp u_fp; /* FP state */ 77*4882a593Smuzhiyun struct user_fp_struct * u_fp0;/* Used by gdb to help find the values for */ 78*4882a593Smuzhiyun /* the FP registers. */ 79*4882a593Smuzhiyun }; 80*4882a593Smuzhiyun #define NBPG PAGE_SIZE 81*4882a593Smuzhiyun #define UPAGES 1 82*4882a593Smuzhiyun #define HOST_TEXT_START_ADDR (u.start_code) 83*4882a593Smuzhiyun #define HOST_STACK_END_ADDR (u.start_stack + u.u_ssize * NBPG) 84*4882a593Smuzhiyun 85*4882a593Smuzhiyun /* 86*4882a593Smuzhiyun * User specific VFP registers. If only VFPv2 is present, registers 16 to 31 87*4882a593Smuzhiyun * are ignored by the ptrace system call and the signal handler. 88*4882a593Smuzhiyun */ 89*4882a593Smuzhiyun struct user_vfp { 90*4882a593Smuzhiyun unsigned long long fpregs[32]; 91*4882a593Smuzhiyun unsigned long fpscr; 92*4882a593Smuzhiyun }; 93*4882a593Smuzhiyun 94*4882a593Smuzhiyun /* 95*4882a593Smuzhiyun * VFP exception registers exposed to user space during signal delivery. 96*4882a593Smuzhiyun * Fields not relavant to the current VFP architecture are ignored. 97*4882a593Smuzhiyun */ 98*4882a593Smuzhiyun struct user_vfp_exc { 99*4882a593Smuzhiyun unsigned long fpexc; 100*4882a593Smuzhiyun unsigned long fpinst; 101*4882a593Smuzhiyun unsigned long fpinst2; 102*4882a593Smuzhiyun }; 103*4882a593Smuzhiyun 104*4882a593Smuzhiyun #endif /* _ARM_USER_H */ 105