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/* Copyright (C) 2005-2017 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 <tls.h>
#ifndef __ASSEMBLER__
# include <nptl/pthreadP.h>
#endif
#if IS_IN (libc) || IS_IN (libpthread) || IS_IN (librt)
# ifndef NO_ERROR
# define NO_ERROR -0x1000
# endif
/* The syscall cancellation mechanism requires userspace
assistance, the following code does roughly this:
do arguments (read arg5 and arg6 to registers)
setup frame
check if there are threads, yes jump to pseudo_cancel
unthreaded:
syscall
check syscall return (jump to pre_end)
set errno
set return to -1
(jump to pre_end)
pseudo_cancel:
cenable
syscall
cdisable
check syscall return (jump to pre_end)
set errno
set return to -1
pre_end
restore stack
It is expected that 'ret' and 'END' macros will
append an 'undo arguments' and 'return' to the
this PSEUDO macro. */
# undef PSEUDO
# define PSEUDO(name, syscall_name, args) \
ENTRY (__##syscall_name##_nocancel) \
DOARGS_##args ASM_LINE_SEP \
stwm TREG, 64(%sp) ASM_LINE_SEP \
.cfi_def_cfa_offset -64 ASM_LINE_SEP \
.cfi_offset TREG, 0 ASM_LINE_SEP \
stw %sp, -4(%sp) ASM_LINE_SEP \
stw %r19, -32(%sp) ASM_LINE_SEP \
.cfi_offset 19, 32 ASM_LINE_SEP \
/* Save r19 */ ASM_LINE_SEP \
SAVE_PIC(TREG) ASM_LINE_SEP \
/* Do syscall, delay loads # */ ASM_LINE_SEP \
ble 0x100(%sr2,%r0) ASM_LINE_SEP \
ldi SYS_ify (syscall_name), %r20 /* delay */ ASM_LINE_SEP \
ldi NO_ERROR,%r1 ASM_LINE_SEP \
cmpb,>>=,n %r1,%ret0,L(pre_nc_end) ASM_LINE_SEP \
/* Restore r19 from TREG */ ASM_LINE_SEP \
LOAD_PIC(TREG) /* delay */ ASM_LINE_SEP \
SYSCALL_ERROR_HANDLER ASM_LINE_SEP \
/* Use TREG for temp storage */ ASM_LINE_SEP \
copy %ret0, TREG /* delay */ ASM_LINE_SEP \
/* OPTIMIZE: Don't reload r19 */ ASM_LINE_SEP \
/* do a -1*syscall_ret0 */ ASM_LINE_SEP \
sub %r0, TREG, TREG ASM_LINE_SEP \
/* Store into errno location */ ASM_LINE_SEP \
stw TREG, 0(%sr0,%ret0) ASM_LINE_SEP \
/* return -1 as error */ ASM_LINE_SEP \
ldi -1, %ret0 ASM_LINE_SEP \
L(pre_nc_end): ASM_LINE_SEP \
/* No need to LOAD_PIC */ ASM_LINE_SEP \
/* Undo frame */ ASM_LINE_SEP \
ldwm -64(%sp),TREG ASM_LINE_SEP \
/* Restore rp before exit */ ASM_LINE_SEP \
ldw -20(%sp), %rp ASM_LINE_SEP \
ret ASM_LINE_SEP \
END(__##syscall_name##_nocancel) ASM_LINE_SEP \
/**********************************************/ASM_LINE_SEP \
ENTRY (name) \
DOARGS_##args ASM_LINE_SEP \
stwm TREG, 64(%sp) ASM_LINE_SEP \
.cfi_def_cfa_offset -64 ASM_LINE_SEP \
.cfi_offset TREG, 0 ASM_LINE_SEP \
stw %sp, -4(%sp) ASM_LINE_SEP \
stw %r19, -32(%sp) ASM_LINE_SEP \
.cfi_offset 19, 32 ASM_LINE_SEP \
/* Done setting up frame, continue... */ ASM_LINE_SEP \
SINGLE_THREAD_P ASM_LINE_SEP \
cmpib,<>,n 0,%ret0,L(pseudo_cancel) ASM_LINE_SEP \
L(unthreaded): ASM_LINE_SEP \
/* Save r19 */ ASM_LINE_SEP \
SAVE_PIC(TREG) ASM_LINE_SEP \
/* Do syscall, delay loads # */ ASM_LINE_SEP \
ble 0x100(%sr2,%r0) ASM_LINE_SEP \
ldi SYS_ify (syscall_name), %r20 /* delay */ ASM_LINE_SEP \
ldi NO_ERROR,%r1 ASM_LINE_SEP \
cmpb,>>=,n %r1,%ret0,L(pre_end) ASM_LINE_SEP \
/* Restore r19 from TREG */ ASM_LINE_SEP \
LOAD_PIC(TREG) /* delay */ ASM_LINE_SEP \
SYSCALL_ERROR_HANDLER ASM_LINE_SEP \
/* Use TREG for temp storage */ ASM_LINE_SEP \
copy %ret0, TREG /* delay */ ASM_LINE_SEP \
/* OPTIMIZE: Don't reload r19 */ ASM_LINE_SEP \
/* do a -1*syscall_ret0 */ ASM_LINE_SEP \
sub %r0, TREG, TREG ASM_LINE_SEP \
/* Store into errno location */ ASM_LINE_SEP \
stw TREG, 0(%sr0,%ret0) ASM_LINE_SEP \
b L(pre_end) ASM_LINE_SEP \
/* return -1 as error */ ASM_LINE_SEP \
ldi -1, %ret0 /* delay */ ASM_LINE_SEP \
L(pseudo_cancel): ASM_LINE_SEP \
PUSHARGS_##args /* Save args */ ASM_LINE_SEP \
/* Save r19 into TREG */ ASM_LINE_SEP \
CENABLE /* FUNC CALL */ ASM_LINE_SEP \
SAVE_PIC(TREG) /* delay */ ASM_LINE_SEP \
/* restore syscall args */ ASM_LINE_SEP \
POPARGS_##args ASM_LINE_SEP \
/* save mask from cenable (use stub rp slot) */ ASM_LINE_SEP \
stw %ret0, -24(%sp) ASM_LINE_SEP \
/* ... SYSCALL ... */ ASM_LINE_SEP \
ble 0x100(%sr2,%r0) ASM_LINE_SEP \
ldi SYS_ify (syscall_name), %r20 /* delay */ ASM_LINE_SEP \
/* ............... */ ASM_LINE_SEP \
LOAD_PIC(TREG) ASM_LINE_SEP \
/* pass mask as arg0 to cdisable */ ASM_LINE_SEP \
ldw -24(%sp), %r26 ASM_LINE_SEP \
CDISABLE ASM_LINE_SEP \
stw %ret0, -24(%sp) /* delay */ ASM_LINE_SEP \
/* Restore syscall return */ ASM_LINE_SEP \
ldw -24(%sp), %ret0 ASM_LINE_SEP \
/* compare error */ ASM_LINE_SEP \
ldi NO_ERROR,%r1 ASM_LINE_SEP \
/* branch if no error */ ASM_LINE_SEP \
cmpb,>>=,n %r1,%ret0,L(pre_end) ASM_LINE_SEP \
LOAD_PIC(TREG) /* cond. nullify */ ASM_LINE_SEP \
copy %ret0, TREG /* save syscall return */ ASM_LINE_SEP \
SYSCALL_ERROR_HANDLER ASM_LINE_SEP \
/* make syscall res value positive */ ASM_LINE_SEP \
sub %r0, TREG, TREG /* delay */ ASM_LINE_SEP \
/* No need to LOAD_PIC */ ASM_LINE_SEP \
/* store into errno location */ ASM_LINE_SEP \
stw TREG, 0(%sr0,%ret0) ASM_LINE_SEP \
/* return -1 */ ASM_LINE_SEP \
ldi -1, %ret0 ASM_LINE_SEP \
L(pre_end): ASM_LINE_SEP \
/* No need to LOAD_PIC */ ASM_LINE_SEP \
/* Undo frame */ ASM_LINE_SEP \
ldwm -64(%sp),TREG ASM_LINE_SEP \
/* Restore rp before exit */ ASM_LINE_SEP \
ldw -20(%sp), %rp ASM_LINE_SEP
/* Save arguments into our frame */
# define PUSHARGS_0 /* nothing to do */
# define PUSHARGS_1 PUSHARGS_0 stw %r26, -36(%sr0,%sp) ASM_LINE_SEP \
.cfi_offset 26, 28 ASM_LINE_SEP
# define PUSHARGS_2 PUSHARGS_1 stw %r25, -40(%sr0,%sp) ASM_LINE_SEP \
.cfi_offset 25, 24 ASM_LINE_SEP
# define PUSHARGS_3 PUSHARGS_2 stw %r24, -44(%sr0,%sp) ASM_LINE_SEP \
.cfi_offset 24, 20 ASM_LINE_SEP
# define PUSHARGS_4 PUSHARGS_3 stw %r23, -48(%sr0,%sp) ASM_LINE_SEP \
.cfi_offset 23, 16 ASM_LINE_SEP
# define PUSHARGS_5 PUSHARGS_4 stw %r22, -52(%sr0,%sp) ASM_LINE_SEP \
.cfi_offset 22, 12 ASM_LINE_SEP
# define PUSHARGS_6 PUSHARGS_5 stw %r21, -56(%sr0,%sp) ASM_LINE_SEP \
.cfi_offset 21, 8 ASM_LINE_SEP
/* Bring them back from the stack */
# define POPARGS_0 /* nothing to do */
# define POPARGS_1 POPARGS_0 ldw -36(%sr0,%sp), %r26 ASM_LINE_SEP
# define POPARGS_2 POPARGS_1 ldw -40(%sr0,%sp), %r25 ASM_LINE_SEP
# define POPARGS_3 POPARGS_2 ldw -44(%sr0,%sp), %r24 ASM_LINE_SEP
# define POPARGS_4 POPARGS_3 ldw -48(%sr0,%sp), %r23 ASM_LINE_SEP
# define POPARGS_5 POPARGS_4 ldw -52(%sr0,%sp), %r22 ASM_LINE_SEP
# define POPARGS_6 POPARGS_5 ldw -56(%sr0,%sp), %r21 ASM_LINE_SEP
# if IS_IN (libpthread)
# ifdef PIC
# define CENABLE .import __pthread_enable_asynccancel,code ASM_LINE_SEP \
bl __pthread_enable_asynccancel,%r2 ASM_LINE_SEP
# define CDISABLE .import __pthread_disable_asynccancel,code ASM_LINE_SEP \
bl __pthread_disable_asynccancel,%r2 ASM_LINE_SEP
# else
# define CENABLE .import __pthread_enable_asynccancel,code ASM_LINE_SEP \
bl __pthread_enable_asynccancel,%r2 ASM_LINE_SEP
# define CDISABLE .import __pthread_disable_asynccancel,code ASM_LINE_SEP \
bl __pthread_disable_asynccancel,%r2 ASM_LINE_SEP
# endif
# elif IS_IN (libc)
# ifdef PIC
# define CENABLE .import __libc_enable_asynccancel,code ASM_LINE_SEP \
bl __libc_enable_asynccancel,%r2 ASM_LINE_SEP
# define CDISABLE .import __libc_disable_asynccancel,code ASM_LINE_SEP \
bl __libc_disable_asynccancel,%r2 ASM_LINE_SEP
# else
# define CENABLE .import __libc_enable_asynccancel,code ASM_LINE_SEP \
bl __libc_enable_asynccancel,%r2 ASM_LINE_SEP
# define CDISABLE .import __libc_disable_asynccancel,code ASM_LINE_SEP \
bl __libc_disable_asynccancel,%r2 ASM_LINE_SEP
# endif
# elif IS_IN (librt)
# ifdef PIC
# define CENABLE .import __librt_enable_asynccancel,code ASM_LINE_SEP \
bl __librt_enable_asynccancel,%r2 ASM_LINE_SEP
# define CDISABLE .import __librt_disable_asynccancel,code ASM_LINE_SEP \
bl __librt_disable_asynccancel,%r2 ASM_LINE_SEP
# else
# define CENABLE .import __librt_enable_asynccancel,code ASM_LINE_SEP \
bl __librt_enable_asynccancel,%r2 ASM_LINE_SEP
# define CDISABLE .import __librt_disable_asynccancel,code ASM_LINE_SEP \
bl __librt_disable_asynccancel,%r2 ASM_LINE_SEP
# endif
# else
# error Unsupported library
# endif
# if IS_IN (libpthread)
# define __local_multiple_threads __pthread_multiple_threads
# elif IS_IN (libc)
# define __local_multiple_threads __libc_multiple_threads
# elif IS_IN (librt)
# define __local_multiple_threads __librt_multiple_threads
# else
# error Unsupported library
# endif
# ifndef __ASSEMBLER__
# define SINGLE_THREAD_P \
__builtin_expect (THREAD_GETMEM (THREAD_SELF, \
header.multiple_threads) == 0, 1)
# else
/* Read the value of header.multiple_threads from the thread pointer */
# define SINGLE_THREAD_P \
mfctl %cr27, %ret0 ASM_LINE_SEP \
ldw MULTIPLE_THREADS_THREAD_OFFSET(%sr0,%ret0),%ret0 ASM_LINE_SEP
# endif
#elif !defined __ASSEMBLER__
/* This code should never be used but we define it anyhow. */
# define SINGLE_THREAD_P (1)
# define NO_CANCELLATION 1
#endif
/* IS_IN (libc) || IS_IN (libpthread) || IS_IN (librt) */
#ifndef __ASSEMBLER__
# define RTLD_SINGLE_THREAD_P \
__builtin_expect (THREAD_GETMEM (THREAD_SELF, \
header.multiple_threads) == 0, 1)
#endif
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