2 /*--------------------------------------------------------------------*/
3 /*--- Support for doing system calls. syscall-arm-linux.S ---*/
4 /*--------------------------------------------------------------------*/
7 This file is part of Valgrind, a dynamic binary instrumentation
10 Copyright (C) 2008-2010 Evan Geller (gaze@bea.ms)
12 This program is free software; you can redistribute it and/or
13 modify it under the terms of the GNU General Public License as
14 published by the Free Software Foundation; either version 2 of the
15 License, or (at your option) any later version.
17 This program is distributed in the hope that it will be useful, but
18 WITHOUT ANY WARRANTY; without even the implied warranty of
19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 General Public License for more details.
22 You should have received a copy of the GNU General Public License
23 along with this program; if not, write to the Free Software
24 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
27 The GNU General Public License is contained in the file COPYING.
30 #if defined(VGP_arm_linux)
32 #include "pub_core_basics_asm.h"
33 #include "pub_core_vkiscnums_asm.h"
34 #include "libvex_guest_offsets.h"
37 /*----------------------------------------------------------------*/
39 Perform a syscall for the client. This will run a syscall
40 with the client's specific per-thread signal mask.
42 The structure of this function is such that, if the syscall is
43 interrupted by a signal, we can determine exactly what
44 execution state we were in with respect to the execution of
45 the syscall by examining the value of IP in the signal
46 handler. This means that we can always do the appropriate
47 thing to precisely emulate the kernel's signal/syscall
50 The syscall number is taken from the argument, even though it
51 should also be in regs->m_R7. The syscall result is written
52 back to regs->m_R0 on completion.
54 Returns 0 if the syscall was successfully called (even if the
55 syscall itself failed), or a nonzero error code in the lowest
56 8 bits if one of the sigprocmasks failed (there's no way to
57 determine which one failed). And there's no obvious way to
58 recover from that either, but nevertheless we want to know.
60 VG_(fixup_guest_state_after_syscall_interrupted) does the
61 thread state fixup in the case where we were interrupted by a
66 UWord ML_(do_syscall_for_client_WRK)(
68 void* guest_state, // r1
69 const vki_sigset_t *sysmask, // r2
70 const vki_sigset_t *postmask, // r3
71 Int nsigwords) // [sp, #0]
74 #define VKI_SIG_SETMASK 2
76 .globl ML_(do_syscall_for_client_WRK)
77 ML_(do_syscall_for_client_WRK):
79 /* Stash callee-saves and our args on the stack */
80 push {r0, r1, r3, r4, r5, r7, fp, lr}
84 mov r7, #__NR_rt_sigprocmask
85 mov r0, #VKI_SIG_SETMASK
86 mov r1, r2 /* sysmask */
87 mov r2, r3 /* postmask */
88 ldr r3, [sp, #32] /* nsigwords */
92 ldr r5, [sp, #4] /* guest_state */
94 ldr r7, [sp, #0] /* syscall# */
95 ldr r0, [r5, #OFFSET_arm_R0]
96 ldr r1, [r5, #OFFSET_arm_R1]
97 ldr r2, [r5, #OFFSET_arm_R2]
98 ldr r3, [r5, #OFFSET_arm_R3]
99 ldr r4, [r5, #OFFSET_arm_R4]
100 ldr r5, [r5, #OFFSET_arm_R5]
104 ldr r5, [sp, #4] /* guest_state */
105 str r0, [r5, #OFFSET_arm_R0]
108 mov r7, #__NR_rt_sigprocmask
109 mov r0, #VKI_SIG_SETMASK
110 ldr r1, [sp, #8] /* postmask */
112 ldr r3, [sp, #32] /* nsigwords */
117 add sp, sp, #4 /* r0 contains return value */
121 pop {r1, r3, r4, r5, r7, fp, pc}
123 7: /* Failure: return 0x8000 | error code */
125 pop {r1, r3, r4, r5, r7, fp, pc}
129 /* export the ranges so that
130 VG_(fixup_guest_state_after_syscall_interrupted) can do the
133 .globl ML_(blksys_setup)
134 .globl ML_(blksys_restart)
135 .globl ML_(blksys_complete)
136 .globl ML_(blksys_committed)
137 .globl ML_(blksys_finished)
138 ML_(blksys_setup): .long 1b
139 ML_(blksys_restart): .long 2b
140 ML_(blksys_complete): .long 3b
141 ML_(blksys_committed): .long 4b
142 ML_(blksys_finished): .long 5b
144 /* Let the linker know we don't need an executable stack */
145 .section .note.GNU-stack,"",%progbits
149 #endif // defined(VGP_arm_linux)
151 /*--------------------------------------------------------------------*/
153 /*--------------------------------------------------------------------*/