| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com) |
| 3 | * Licensed under the GPL |
| 4 | */ |
| 5 | |
| 6 | #include <unistd.h> |
| 7 | #include <signal.h> |
| 8 | #include <errno.h> |
| 9 | #include <asm/unistd.h> |
| 10 | #include "sysdep/ptrace.h" |
| 11 | #include "sigcontext.h" |
| 12 | #include "ptrace_user.h" |
| 13 | #include "task.h" |
| 14 | #include "user_util.h" |
| 15 | #include "kern_util.h" |
| 16 | #include "syscall_user.h" |
| 17 | #include "tt.h" |
| 18 | |
| 19 | |
| 20 | void syscall_handler_tt(int sig, union uml_pt_regs *regs) |
| 21 | { |
| 22 | void *sc; |
| 23 | long result; |
| 24 | int syscall; |
| 25 | #ifdef UML_CONFIG_DEBUG_SYSCALL |
| 26 | int index; |
| 27 | #endif |
| 28 | |
| 29 | syscall = UPT_SYSCALL_NR(regs); |
| 30 | sc = UPT_SC(regs); |
| 31 | SC_START_SYSCALL(sc); |
| 32 | |
| 33 | #ifdef UML_CONFIG_DEBUG_SYSCALL |
| 34 | index = record_syscall_start(syscall); |
| 35 | #endif |
| 36 | syscall_trace(regs, 0); |
| 37 | result = execute_syscall_tt(regs); |
| 38 | |
| 39 | /* regs->sc may have changed while the system call ran (there may |
| 40 | * have been an interrupt or segfault), so it needs to be refreshed. |
| 41 | */ |
| 42 | UPT_SC(regs) = sc; |
| 43 | |
| 44 | SC_SET_SYSCALL_RETURN(sc, result); |
| 45 | |
| 46 | syscall_trace(regs, 1); |
| 47 | #ifdef UML_CONFIG_DEBUG_SYSCALL |
| 48 | record_syscall_end(index, result); |
| 49 | #endif |
| 50 | } |
| 51 | |
| 52 | void do_sigtrap(void *task) |
| 53 | { |
| 54 | UPT_SYSCALL_NR(TASK_REGS(task)) = -1; |
| 55 | } |
| 56 | |
| 57 | void do_syscall(void *task, int pid, int local_using_sysemu) |
| 58 | { |
| 59 | unsigned long proc_regs[FRAME_SIZE]; |
| 60 | |
| 61 | if(ptrace_getregs(pid, proc_regs) < 0) |
| 62 | tracer_panic("Couldn't read registers"); |
| 63 | |
| 64 | UPT_SYSCALL_NR(TASK_REGS(task)) = PT_SYSCALL_NR(proc_regs); |
| 65 | |
| 66 | if(((unsigned long *) PT_IP(proc_regs) >= &_stext) && |
| 67 | ((unsigned long *) PT_IP(proc_regs) <= &_etext)) |
| 68 | tracer_panic("I'm tracing myself and I can't get out"); |
| 69 | |
| 70 | /* advanced sysemu mode set syscall number to -1 automatically */ |
| 71 | if (local_using_sysemu==2) |
| 72 | return; |
| 73 | |
| 74 | /* syscall number -1 in sysemu skips syscall restarting in host */ |
| 75 | if(ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_NR_OFFSET, |
| 76 | local_using_sysemu ? -1 : __NR_getpid) < 0) |
| 77 | tracer_panic("do_syscall : Nullifying syscall failed, " |
| 78 | "errno = %d", errno); |
| 79 | } |
| 80 | |
| 81 | /* |
| 82 | * Overrides for Emacs so that we follow Linus's tabbing style. |
| 83 | * Emacs will notice this stuff at the end of the file and automatically |
| 84 | * adjust the settings for this buffer only. This must remain at the end |
| 85 | * of the file. |
| 86 | * --------------------------------------------------------------------------- |
| 87 | * Local variables: |
| 88 | * c-file-style: "linux" |
| 89 | * End: |
| 90 | */ |