1 2 /*--------------------------------------------------------------------*/ 3 /*--- Support for doing system calls. syscall-amd64-darwin.S ---*/ 4 /*--------------------------------------------------------------------*/ 5 6 /* 7 This file is part of Valgrind, a dynamic binary instrumentation 8 framework. 9 10 Copyright (C) 2000-2012 Julian Seward 11 jseward (at) acm.org 12 13 This program is free software; you can redistribute it and/or 14 modify it under the terms of the GNU General Public License as 15 published by the Free Software Foundation; either version 2 of the 16 License, or (at your option) any later version. 17 18 This program is distributed in the hope that it will be useful, but 19 WITHOUT ANY WARRANTY; without even the implied warranty of 20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 21 General Public License for more details. 22 23 You should have received a copy of the GNU General Public License 24 along with this program; if not, write to the Free Software 25 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 26 02111-1307, USA. 27 28 The GNU General Public License is contained in the file COPYING. 29 */ 30 31 #if defined(VGP_amd64_darwin) 32 33 #include "pub_core_basics_asm.h" 34 #include "pub_core_vkiscnums_asm.h" 35 #include "libvex_guest_offsets.h" 36 37 38 /*----------------------------------------------------------------*/ 39 /* 40 Perform a syscall for the client. This will run a syscall 41 with the client's specific per-thread signal mask. 42 43 The structure of this function is such that, if the syscall is 44 interrupted by a signal, we can determine exactly what 45 execution state we were in with respect to the execution of 46 the syscall by examining the value of %eip in the signal 47 handler. This means that we can always do the appropriate 48 thing to precisely emulate the kernel's signal/syscall 49 interactions. 50 51 The syscall number is taken from the argument, even though it 52 should also be in guest_state->guest_RAX. The syscall result 53 is written back to guest_state->guest_RAX on completion. 54 55 Returns 0 if the syscall was successfully called (even if the 56 syscall itself failed), or a -ve error code if one of the 57 sigprocmasks failed (there's no way to determine which one 58 failed). 59 60 VG_(fixup_guest_state_after_syscall_interrupted) does the 61 thread state fixup in the case where we were interrupted by a 62 signal. 63 64 Prototype: 65 66 Int ML_(do_syscall_for_client_WRK( 67 Int syscallno, // rdi 68 void* guest_state, // rsi 69 const vki_sigset_t *sysmask, // rdx 70 const vki_sigset_t *postmask, // rcx 71 Int sigsetSzB) // r8 72 73 Note that sigsetSzB is totally ignored (and irrelevant). 74 */ 75 76 /* from vki_arch.h */ 77 #define VKI_SIG_SETMASK 3 78 79 /* DO_SYSCALL MACH|MDEP|UNIX */ 80 #define MACH 1 81 #define MDEP 2 82 #define UNIX 3 83 84 .macro DO_SYSCALL 85 /* save callee-saved regs */ 86 pushq %rbp 87 movq %rsp, %rbp 88 // stack is now aligned 89 pushq %rdi // -8(%rbp) syscallno 90 pushq %rsi // -16(%rbp) guest_state 91 pushq %rdx // -24(%rbp) sysmask 92 pushq %rcx // -32(%rbp) postmask 93 pushq %r8 // -40(%rbp) sigsetSzB 94 // stack is now aligned 95 96 L_$0_1: /* Even though we can't take a signal until the sigprocmask completes, 97 start the range early. 98 If rip is in the range [1,2), the syscall hasn't been started yet */ 99 100 /* Set the signal mask which should be current during the syscall. */ 101 /* GrP fixme signals 102 DDD: JRS fixme: use __NR___pthread_sigmask, not __NR_rt_sigprocmask 103 movq $__NR_rt_sigprocmask, %rax // syscall # 104 movq $VKI_SIG_SETMASK, %rdi // how 105 movq -24(%rbp), %rsi // sysmask 106 movq -32(%rbp), %rdx // postmask 107 movq -40(%rbp), %r10 // sigsetSzB in r10 not rcx 108 DDD: fixme return address 109 syscall 110 111 jnc 7f // sigprocmask failed 112 */ 113 114 /* OK, that worked. Now do the syscall proper. */ 115 116 /* 6 register parameters */ 117 movq -16(%rbp), %r11 /* r11 = VexGuestAMD64State * */ 118 movq OFFSET_amd64_RDI(%r11), %rdi 119 movq OFFSET_amd64_RSI(%r11), %rsi 120 movq OFFSET_amd64_RDX(%r11), %rdx 121 movq OFFSET_amd64_RCX(%r11), %r10 /* rcx is passed in r10 instead */ 122 movq OFFSET_amd64_R8(%r11), %r8 123 movq OFFSET_amd64_R9(%r11), %r9 124 /* 2 stack parameters plus return address (ignored by syscall) */ 125 movq OFFSET_amd64_RSP(%r11), %r11 /* r11 = simulated RSP */ 126 movq 16(%r11), %rax 127 pushq %rax 128 movq 8(%r11), %rax 129 pushq %rax 130 /* stack is currently aligned - return address misaligns */ 131 movq 0(%r11), %rax 132 pushq %rax 133 /* syscallno */ 134 movq -8(%rbp), %rax 135 136 /* If rip==2, then the syscall was either just about 137 to start, or was interrupted and the kernel was 138 restarting it. */ 139 L_$0_2: syscall 140 L_$0_3: /* In the range [3, 4), the syscall result is in %rax, 141 but hasn't been committed to RAX. */ 142 143 /* stack contents: 3 words for syscall above, plus our prologue */ 144 setc 0(%rsp) /* stash returned carry flag */ 145 146 movq -16(%rbp), %r11 /* r11 = VexGuestAMD64State * */ 147 movq %rax, OFFSET_amd64_RAX(%r11) /* save back to RAX */ 148 movq %rdx, OFFSET_amd64_RDX(%r11) /* save back to RDX */ 149 150 .if $0 == UNIX 151 /* save carry flag to VEX */ 152 xor %rax, %rax 153 movb 0(%rsp), %al 154 movq %rax, %rdi /* arg1 = new flag */ 155 movq %r11, %rsi /* arg2 = vex state */ 156 addq $$24, %rsp /* remove syscall parameters */ 157 call _LibVEX_GuestAMD64_put_rflag_c 158 .else 159 addq $$24, %rsp /* remove syscall parameters*/ 160 .endif 161 162 L_$0_4: /* Re-block signals. If eip is in [4,5), then the syscall 163 is complete and we needn't worry about it. */ 164 /* GrP fixme signals 165 DDD: JRS fixme: use __NR___pthread_sigmask, not __NR_rt_sigprocmask 166 PUSH_di_si_dx_cx_8 167 168 movq $__NR_rt_sigprocmask, %rax // syscall # 169 movq $VKI_SIG_SETMASK, %rdi // how 170 movq %rcx, %rsi // postmask 171 xorq %rdx, %rdx // NULL 172 movq %r8, %r10 // sigsetSzB 173 DDD: fixme return address 174 syscall 175 176 POP_di_si_dx_cx_8 177 178 jnc 7f // sigprocmask failed 179 */ 180 L_$0_5: /* now safe from signals */ 181 movq $$0, %rax /* SUCCESS */ 182 movq %rbp, %rsp 183 popq %rbp 184 ret 185 186 /* GrP fixme signals 187 L_$0_7: // failure: return 0x8000 | error code 188 DDD: fixme return value 189 movq %rbp, %rsp 190 popq %rbp 191 ret 192 */ 193 194 .endmacro 195 196 197 .globl ML_(do_syscall_for_client_unix_WRK) 198 ML_(do_syscall_for_client_unix_WRK): 199 DO_SYSCALL UNIX 200 201 .globl ML_(do_syscall_for_client_mach_WRK) 202 ML_(do_syscall_for_client_mach_WRK): 203 DO_SYSCALL MACH 204 205 .globl ML_(do_syscall_for_client_mdep_WRK) 206 ML_(do_syscall_for_client_mdep_WRK): 207 DO_SYSCALL MDEP 208 209 .data 210 /* export the ranges so that 211 VG_(fixup_guest_state_after_syscall_interrupted) can do the 212 right thing */ 213 214 /* eg MK_L_SCLASS_N(UNIX,99) produces L_3_99 215 since UNIX is #defined to 3 at the top of this file */ 216 #define FOO(scclass,labelno) L_##scclass##_##labelno 217 #define MK_L_SCCLASS_N(scclass,labelno) FOO(scclass,labelno) 218 219 .globl ML_(blksys_setup_MACH) 220 .globl ML_(blksys_restart_MACH) 221 .globl ML_(blksys_complete_MACH) 222 .globl ML_(blksys_committed_MACH) 223 .globl ML_(blksys_finished_MACH) 224 ML_(blksys_setup_MACH): .quad MK_L_SCCLASS_N(MACH,1) 225 ML_(blksys_restart_MACH): .quad MK_L_SCCLASS_N(MACH,2) 226 ML_(blksys_complete_MACH): .quad MK_L_SCCLASS_N(MACH,3) 227 ML_(blksys_committed_MACH): .quad MK_L_SCCLASS_N(MACH,4) 228 ML_(blksys_finished_MACH): .quad MK_L_SCCLASS_N(MACH,5) 229 230 .globl ML_(blksys_setup_MDEP) 231 .globl ML_(blksys_restart_MDEP) 232 .globl ML_(blksys_complete_MDEP) 233 .globl ML_(blksys_committed_MDEP) 234 .globl ML_(blksys_finished_MDEP) 235 ML_(blksys_setup_MDEP): .quad MK_L_SCCLASS_N(MDEP,1) 236 ML_(blksys_restart_MDEP): .quad MK_L_SCCLASS_N(MDEP,2) 237 ML_(blksys_complete_MDEP): .quad MK_L_SCCLASS_N(MDEP,3) 238 ML_(blksys_committed_MDEP): .quad MK_L_SCCLASS_N(MDEP,4) 239 ML_(blksys_finished_MDEP): .quad MK_L_SCCLASS_N(MDEP,5) 240 241 .globl ML_(blksys_setup_UNIX) 242 .globl ML_(blksys_restart_UNIX) 243 .globl ML_(blksys_complete_UNIX) 244 .globl ML_(blksys_committed_UNIX) 245 .globl ML_(blksys_finished_UNIX) 246 ML_(blksys_setup_UNIX): .quad MK_L_SCCLASS_N(UNIX,1) 247 ML_(blksys_restart_UNIX): .quad MK_L_SCCLASS_N(UNIX,2) 248 ML_(blksys_complete_UNIX): .quad MK_L_SCCLASS_N(UNIX,3) 249 ML_(blksys_committed_UNIX): .quad MK_L_SCCLASS_N(UNIX,4) 250 ML_(blksys_finished_UNIX): .quad MK_L_SCCLASS_N(UNIX,5) 251 252 #endif // defined(VGP_amd64_darwin) 253 254 /*--------------------------------------------------------------------*/ 255 /*--- end ---*/ 256 /*--------------------------------------------------------------------*/ 257
