1 /* 2 * Copyright (C) 2004 Jeff Dike (jdike@addtoit.com) 3 * Licensed under the GPL 4 */ 5 6 #ifndef __SYSDEP_STUB_H 7 #define __SYSDEP_STUB_H 8 9 #include <asm/ptrace.h> 10 #include <generated/asm-offsets.h> 11 12 #define STUB_MMAP_NR __NR_mmap2 13 #define MMAP_OFFSET(o) ((o) >> UM_KERN_PAGE_SHIFT) 14 15 static inline long stub_syscall0(long syscall) 16 { 17 long ret; 18 19 __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall)); 20 21 return ret; 22 } 23 24 static inline long stub_syscall1(long syscall, long arg1) 25 { 26 long ret; 27 28 __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1)); 29 30 return ret; 31 } 32 33 static inline long stub_syscall2(long syscall, long arg1, long arg2) 34 { 35 long ret; 36 37 __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1), 38 "c" (arg2)); 39 40 return ret; 41 } 42 43 static inline long stub_syscall3(long syscall, long arg1, long arg2, long arg3) 44 { 45 long ret; 46 47 __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1), 48 "c" (arg2), "d" (arg3)); 49 50 return ret; 51 } 52 53 static inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3, 54 long arg4) 55 { 56 long ret; 57 58 __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1), 59 "c" (arg2), "d" (arg3), "S" (arg4)); 60 61 return ret; 62 } 63 64 static inline long stub_syscall5(long syscall, long arg1, long arg2, long arg3, 65 long arg4, long arg5) 66 { 67 long ret; 68 69 __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1), 70 "c" (arg2), "d" (arg3), "S" (arg4), "D" (arg5)); 71 72 return ret; 73 } 74 75 static inline void trap_myself(void) 76 { 77 __asm("int3"); 78 } 79 80 static inline void remap_stack_and_trap(void) 81 { 82 __asm__ volatile ( 83 "movl %%esp,%%ebx ;" 84 "andl %0,%%ebx ;" 85 "movl %1,%%eax ;" 86 "movl %%ebx,%%edi ; addl %2,%%edi ; movl (%%edi),%%edi ;" 87 "movl %%ebx,%%ebp ; addl %3,%%ebp ; movl (%%ebp),%%ebp ;" 88 "int $0x80 ;" 89 "addl %4,%%ebx ; movl %%eax, (%%ebx) ;" 90 "int $3" 91 : : 92 "g" (~(UM_KERN_PAGE_SIZE - 1)), 93 "g" (STUB_MMAP_NR), 94 "g" (UML_STUB_FIELD_FD), 95 "g" (UML_STUB_FIELD_OFFSET), 96 "g" (UML_STUB_FIELD_CHILD_ERR), 97 "c" (UM_KERN_PAGE_SIZE), 98 "d" (PROT_READ | PROT_WRITE), 99 "S" (MAP_FIXED | MAP_SHARED) 100 : 101 "memory"); 102 } 103 104 static __always_inline void *get_stub_page(void) 105 { 106 unsigned long ret; 107 108 asm volatile ( 109 "movl %%esp,%0 ;" 110 "andl %1,%0" 111 : "=a" (ret) 112 : "g" (~(UM_KERN_PAGE_SIZE - 1))); 113 114 return (void *)ret; 115 } 116 #endif 117