| |
| /*--------------------------------------------------------------------*/ |
| /*--- Support for doing system calls. syscall-x86-darwin.S ---*/ |
| /*--------------------------------------------------------------------*/ |
| |
| /* |
| This file is part of Valgrind, a dynamic binary instrumentation |
| framework. |
| |
| Copyright (C) 2000-2015 Julian Seward |
| jseward@acm.org |
| |
| This program is free software; you can redistribute it and/or |
| modify it under the terms of the GNU General Public License as |
| published by the Free Software Foundation; either version 2 of the |
| License, or (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307, USA. |
| |
| The GNU General Public License is contained in the file COPYING. |
| */ |
| |
| #include "pub_core_basics_asm.h" |
| |
| #if defined(VGP_x86_darwin) |
| |
| #include "pub_core_vkiscnums_asm.h" |
| #include "libvex_guest_offsets.h" |
| |
| |
| /*----------------------------------------------------------------*/ |
| /* |
| Perform a syscall for the client. This will run a syscall |
| with the client's specific per-thread signal mask. |
| |
| The structure of this function is such that, if the syscall is |
| interrupted by a signal, we can determine exactly what |
| execution state we were in with respect to the execution of |
| the syscall by examining the value of %eip in the signal |
| handler. This means that we can always do the appropriate |
| thing to precisely emulate the kernel's signal/syscall |
| interactions. |
| |
| The syscall number is taken from the argument, even though it |
| should also be in regs->m_eax. The syscall result is written |
| back to regs->m_eax on completion. |
| |
| Returns 0 if the syscall was successfully called (even if the |
| syscall itself failed), or a -ve error code if one of the |
| sigprocmasks failed (there's no way to determine which one |
| failed). |
| |
| VG_(fixup_guest_state_after_syscall_interrupted) does the |
| thread state fixup in the case where we were interrupted by a |
| signal. |
| |
| Prototype: |
| |
| Int ML_(do_syscall_for_client_WRK)( |
| Int syscallno, // ebp+8 |
| void* guest_state, // ebp+12 |
| const vki_sigset_t *sysmask, // ebp+16 |
| const vki_sigset_t *postmask, // ebp+20 |
| Int sigsetSzB) // ebp+24 |
| |
| Note that sigsetSzB is totally ignored (and irrelevant). |
| */ |
| |
| /* from vki-darwin.h, checked at startup by m_vki.c */ |
| #define VKI_SIG_SETMASK 3 |
| |
| /* DO_SYSCALL MACH|MDEP|UNIX */ |
| #define MACH 1 |
| #define MDEP 2 |
| #define UNIX 3 |
| |
| .macro DO_SYSCALL |
| /* establish stack frame */ |
| push %ebp |
| mov %esp, %ebp |
| subl $$8, %esp /* 16-byte align stack */ |
| |
| L_$0_1: /* Even though we can't take a signal until the |
| __pthread_sigmask completes, start the range early. |
| If eip is in the range [1,2), the syscall hasn't been started yet */ |
| |
| /* Set the signal mask which should be current during the syscall. */ |
| /* Set up for __pthread_sigmask(SIG_SETMASK, sysmask, postmask) */ |
| pushl 20(%ebp) |
| pushl 16(%ebp) |
| pushl $$VKI_SIG_SETMASK |
| pushl $$0xcafebabe /* totally fake return address */ |
| movl $$__NR___pthread_sigmask, %eax |
| int $$0x80 /* should be sysenter? */ |
| jc L_$0_7 /* __pthread_sigmask failed */ |
| addl $$16,%esp |
| |
| /* Copy syscall parameters to the stack - assume no more than 8 |
| * plus the return address */ |
| /* do_syscall8 */ |
| /* stack is currently aligned assuming 8 parameters */ |
| movl 12(%ebp), %edx |
| movl OFFSET_x86_ESP(%edx), %edx /* edx = simulated ESP */ |
| movl 28+4(%edx), %eax |
| pushl %eax |
| movl 24+4(%edx), %eax |
| pushl %eax |
| movl 20+4(%edx), %eax |
| pushl %eax |
| movl 16+4(%edx), %eax |
| pushl %eax |
| movl 12+4(%edx), %eax |
| pushl %eax |
| movl 8+4(%edx), %eax |
| pushl %eax |
| movl 4+4(%edx), %eax |
| pushl %eax |
| movl 0+4(%edx), %eax |
| pushl %eax |
| /* return address */ |
| movl 0(%edx), %eax |
| pushl %eax |
| |
| /* Put syscall number in eax */ |
| movl 8(%ebp), %eax |
| |
| /* If eip==2, then the syscall was either just about to start, |
| or was interrupted and the kernel was restarting it. */ |
| L_$0_2: |
| .if $0 == UNIX |
| int $$0x80 /* UNIX (GrP fixme should be sysenter?) */ |
| .elseif $0 == MACH |
| int $$0x81 |
| .elseif $0 == MDEP |
| int $$0x82 |
| .else |
| error$0 x |
| .endif |
| |
| L_$0_3: /* In the range [3, 4), the syscall result is in %eax and %edx and C, |
| but hasn't been committed to the thread state. */ |
| setc 0(%esp) /* stash returned carry flag */ |
| movl 12(%ebp), %ecx |
| movl %eax, OFFSET_x86_EAX(%ecx) /* save EAX to vex */ |
| movl %edx, OFFSET_x86_EDX(%ecx) /* save EDX to vex */ |
| .if $0 == UNIX |
| /* UNIX: save carry flag to vex */ |
| subl $$12, %esp |
| movl %ecx, 4(%esp) |
| movl $$0, 0(%esp) |
| movb 12(%esp), %al |
| movb %al, 0(%esp) |
| call _LibVEX_GuestX86_put_eflag_c |
| addl $$12, %esp |
| .endif |
| |
| L_$0_4: /* Re-block signals. If eip is in [4,5), then the syscall is |
| complete and we needn't worry about it. */ |
| /* Set up for __pthread_sigmask(SIG_SETMASK, postmask, NULL) */ |
| pushl $$0 |
| pushl 20(%ebp) |
| pushl $$VKI_SIG_SETMASK |
| pushl $$0xcafef00d /* totally fake return address */ |
| movl $$__NR___pthread_sigmask, %eax |
| int $$0x80 /* should be sysenter? */ |
| jc L_$0_7 /* __pthread_sigmask failed */ |
| addl $$16,%esp |
| |
| L_$0_5: /* now safe from signals */ |
| movl $$0, %eax /* SUCCESS */ |
| movl %ebp, %esp |
| popl %ebp |
| ret |
| |
| L_$0_7: /* failure: return 0x8000 | error code */ |
| /* Note that we enter here with %esp being 16 too low |
| (4 extra words on the stack). But because we're nuking |
| the stack frame now, that doesn't matter. */ |
| andl $$0x7FFF, %eax |
| orl $$0x8000, %eax |
| movl %ebp, %esp |
| popl %ebp |
| ret |
| |
| .endmacro |
| |
| |
| .globl ML_(do_syscall_for_client_unix_WRK) |
| ML_(do_syscall_for_client_unix_WRK): |
| DO_SYSCALL UNIX |
| |
| .globl ML_(do_syscall_for_client_mach_WRK) |
| ML_(do_syscall_for_client_mach_WRK): |
| DO_SYSCALL MACH |
| |
| .globl ML_(do_syscall_for_client_mdep_WRK) |
| ML_(do_syscall_for_client_mdep_WRK): |
| DO_SYSCALL MDEP |
| |
| .data |
| /* export the ranges so that |
| VG_(fixup_guest_state_after_syscall_interrupted) can do the |
| right thing */ |
| |
| /* eg MK_L_SCLASS_N(UNIX,99) produces L_3_99 |
| since UNIX is #defined to 3 at the top of this file */ |
| #define FOO(scclass,labelno) L_##scclass##_##labelno |
| #define MK_L_SCCLASS_N(scclass,labelno) FOO(scclass,labelno) |
| |
| .globl ML_(blksys_setup_MACH) |
| .globl ML_(blksys_restart_MACH) |
| .globl ML_(blksys_complete_MACH) |
| .globl ML_(blksys_committed_MACH) |
| .globl ML_(blksys_finished_MACH) |
| ML_(blksys_setup_MACH): .long MK_L_SCCLASS_N(MACH,1) |
| ML_(blksys_restart_MACH): .long MK_L_SCCLASS_N(MACH,2) |
| ML_(blksys_complete_MACH): .long MK_L_SCCLASS_N(MACH,3) |
| ML_(blksys_committed_MACH): .long MK_L_SCCLASS_N(MACH,4) |
| ML_(blksys_finished_MACH): .long MK_L_SCCLASS_N(MACH,5) |
| |
| .globl ML_(blksys_setup_MDEP) |
| .globl ML_(blksys_restart_MDEP) |
| .globl ML_(blksys_complete_MDEP) |
| .globl ML_(blksys_committed_MDEP) |
| .globl ML_(blksys_finished_MDEP) |
| ML_(blksys_setup_MDEP): .long MK_L_SCCLASS_N(MDEP,1) |
| ML_(blksys_restart_MDEP): .long MK_L_SCCLASS_N(MDEP,2) |
| ML_(blksys_complete_MDEP): .long MK_L_SCCLASS_N(MDEP,3) |
| ML_(blksys_committed_MDEP): .long MK_L_SCCLASS_N(MDEP,4) |
| ML_(blksys_finished_MDEP): .long MK_L_SCCLASS_N(MDEP,5) |
| |
| .globl ML_(blksys_setup_UNIX) |
| .globl ML_(blksys_restart_UNIX) |
| .globl ML_(blksys_complete_UNIX) |
| .globl ML_(blksys_committed_UNIX) |
| .globl ML_(blksys_finished_UNIX) |
| ML_(blksys_setup_UNIX): .long MK_L_SCCLASS_N(UNIX,1) |
| ML_(blksys_restart_UNIX): .long MK_L_SCCLASS_N(UNIX,2) |
| ML_(blksys_complete_UNIX): .long MK_L_SCCLASS_N(UNIX,3) |
| ML_(blksys_committed_UNIX): .long MK_L_SCCLASS_N(UNIX,4) |
| ML_(blksys_finished_UNIX): .long MK_L_SCCLASS_N(UNIX,5) |
| |
| #endif // defined(VGP_x86_darwin) |
| |
| /* Let the linker know we don't need an executable stack */ |
| MARK_STACK_NO_EXEC |
| |
| /*--------------------------------------------------------------------*/ |
| /*--- end ---*/ |
| /*--------------------------------------------------------------------*/ |
