/* Copyright (C) 2005-2016 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_offset TREG, 0 ASM_LINE_SEP \ .cfi_adjust_cfa_offset 64 ASM_LINE_SEP \ stw %sp, -4(%sp) ASM_LINE_SEP \ .cfi_offset 30, -4 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 \ .cfi_adjust_cfa_offset -64 ASM_LINE_SEP \ /* Restore rp before exit */ ASM_LINE_SEP \ ldw -20(%sp), %rp ASM_LINE_SEP \ .cfi_restore 2 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_adjust_cfa_offset 64 ASM_LINE_SEP \ stw %sp, -4(%sp) ASM_LINE_SEP \ .cfi_offset 30, -4 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 \ .cfi_adjust_cfa_offset -64 ASM_LINE_SEP \ /* Restore rp before exit */ ASM_LINE_SEP \ ldw -20(%sp), %rp ASM_LINE_SEP \ .cfi_restore 2 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, -36 ASM_LINE_SEP # define PUSHARGS_2 PUSHARGS_1 stw %r25, -40(%sr0,%sp) ASM_LINE_SEP \ .cfi_offset 25, -40 ASM_LINE_SEP # define PUSHARGS_3 PUSHARGS_2 stw %r24, -44(%sr0,%sp) ASM_LINE_SEP \ .cfi_offset 24, -44 ASM_LINE_SEP # define PUSHARGS_4 PUSHARGS_3 stw %r23, -48(%sr0,%sp) ASM_LINE_SEP \ .cfi_offset 23, -48 ASM_LINE_SEP # define PUSHARGS_5 PUSHARGS_4 stw %r22, -52(%sr0,%sp) ASM_LINE_SEP \ .cfi_offset 22, -52 ASM_LINE_SEP # define PUSHARGS_6 PUSHARGS_5 stw %r21, -56(%sr0,%sp) ASM_LINE_SEP \ .cfi_offset 21, -56 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 \ .cfi_restore 26 ASM_LINE_SEP # define POPARGS_2 POPARGS_1 ldw -40(%sr0,%sp), %r25 ASM_LINE_SEP \ .cfi_restore 25 ASM_LINE_SEP # define POPARGS_3 POPARGS_2 ldw -44(%sr0,%sp), %r24 ASM_LINE_SEP \ .cfi_restore 24 ASM_LINE_SEP # define POPARGS_4 POPARGS_3 ldw -48(%sr0,%sp), %r23 ASM_LINE_SEP \ .cfi_restore 23 ASM_LINE_SEP # define POPARGS_5 POPARGS_4 ldw -52(%sr0,%sp), %r22 ASM_LINE_SEP \ .cfi_restore 22 ASM_LINE_SEP # define POPARGS_6 POPARGS_5 ldw -56(%sr0,%sp), %r21 ASM_LINE_SEP \ .cfi_restore 21 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