diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/i386/syscall_cancel.S')
| -rw-r--r-- | sysdeps/unix/sysv/linux/i386/syscall_cancel.S | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/i386/syscall_cancel.S b/sysdeps/unix/sysv/linux/i386/syscall_cancel.S new file mode 100644 index 0000000000..46fb746da0 --- /dev/null +++ b/sysdeps/unix/sysv/linux/i386/syscall_cancel.S @@ -0,0 +1,104 @@ +/* Cancellable syscall wrapper. Linux/i686 version. + Copyright (C) 2023 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <sysdep.h> +#include <descr-const.h> + +/* long int [eax] __syscall_cancel_arch (int *cancelhandling [SP], + long int nr [SP+4], + long int arg1 [SP+8], + long int arg2 [SP+12], + long int arg3 [SP+16], + long int arg4 [SP+20], + long int arg5 [SP+24], + long int arg6 [SP+28]) */ + +ENTRY (__syscall_cancel_arch) + pushl %ebp + cfi_def_cfa_offset (8) + cfi_offset (ebp, -8) + pushl %edi + cfi_def_cfa_offset (12) + cfi_offset (edi, -12) + pushl %esi + cfi_def_cfa_offset (16) + cfi_offset (esi, -16) + pushl %ebx + cfi_def_cfa_offset (20) + cfi_offset (ebx, -20) + + .global __syscall_cancel_arch_start +__syscall_cancel_arch_start: + + /* if (*cancelhandling & CANCELED_BITMASK) + __syscall_do_cancel() */ + movl 20(%esp), %eax + testb $TCB_CANCELED_BITMASK, (%eax) + jne 1f + + /* Issue a 6 argument syscall, the nr [%eax] being the syscall + number. */ + movl 24(%esp), %eax + movl 28(%esp), %ebx + movl 32(%esp), %ecx + movl 36(%esp), %edx + movl 40(%esp), %esi + movl 44(%esp), %edi + movl 48(%esp), %ebp + + /* We can not use the vDSO helper for syscall (__kernel_vsyscall) + because the returned PC from kernel will point to the vDSO page + instead of the expected __syscall_cancel_arch_{start,end} + marks. */ + int $0x80 + + .global __syscall_cancel_arch_end +__syscall_cancel_arch_end: + + popl %ebx + cfi_restore (ebx) + cfi_def_cfa_offset (16) + popl %esi + cfi_restore (esi) + cfi_def_cfa_offset (12) + popl %edi + cfi_restore (edi) + cfi_def_cfa_offset (8) + popl %ebp + cfi_restore (ebp) + cfi_def_cfa_offset (4) + ret + +1: + /* Although the __syscall_do_cancel do not return, we need to stack + being set correctly for unwind. */ + popl %ebx + cfi_restore (ebx) + cfi_def_cfa_offset (16) + popl %esi + cfi_restore (esi) + cfi_def_cfa_offset (12) + popl %edi + cfi_restore (edi) + cfi_def_cfa_offset (8) + popl %ebp + cfi_restore (ebp) + cfi_def_cfa_offset (4) + jmp __syscall_do_cancel + +END (__syscall_cancel_arch) |