diff options
Diffstat (limited to 'sysdeps/mach/hurd/alpha/trampoline.c')
-rw-r--r-- | sysdeps/mach/hurd/alpha/trampoline.c | 249 |
1 files changed, 0 insertions, 249 deletions
diff --git a/sysdeps/mach/hurd/alpha/trampoline.c b/sysdeps/mach/hurd/alpha/trampoline.c deleted file mode 100644 index 2360cbb469..0000000000 --- a/sysdeps/mach/hurd/alpha/trampoline.c +++ /dev/null @@ -1,249 +0,0 @@ -/* Set thread_state for sighandler, and sigcontext to recover. Alpha version. - Copyright (C) 1994,95,97,98,2002 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, write to the Free - Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA - 02111-1307 USA. */ - -#include <hurd/signal.h> -#include "thread_state.h" -#include "hurdfault.h" -#include <assert.h> - -struct mach_msg_trap_args - { - /* This is the order of arguments to mach_msg_trap. */ - mach_msg_header_t *msg; - mach_msg_option_t option; - mach_msg_size_t send_size; - mach_msg_size_t rcv_size; - mach_port_t rcv_name; - mach_msg_timeout_t timeout; - mach_port_t notify; - }; - - -struct sigcontext * -_hurd_setup_sighandler (struct hurd_sigstate *ss, __sighandler_t handler, - int signo, struct hurd_signal_detail *detail, - int rpc_wait, struct machine_thread_all_state *state) -{ - __label__ trampoline, rpc_wait_trampoline; - void *sigsp; - struct sigcontext *scp; - - if (ss->context) - { - /* We have a previous sigcontext that sigreturn was about - to restore when another signal arrived. We will just base - our setup on that. */ - if (! _hurdsig_catch_memory_fault (ss->context)) - { - memcpy (&state->basic, &ss->context->sc_alpha_thread_state, - sizeof (state->basic)); - memcpy (&state->exc, &ss->context->sc_alpha_exc_state, - sizeof (state->exc)); - state->set = (1 << ALPHA_THREAD_STATE) | (1 << ALPHA_EXC_STATE); - if (state->exc.used_fpa) - { - memcpy (&state->fpu, &ss->context->sc_alpha_float_state, - sizeof (state->fpu)); - state->set |= (1 << ALPHA_FLOAT_STATE); - } - assert (! rpc_wait); - /* The intr_port slot was cleared before sigreturn sent us the - sig_post that made us notice this pending signal, so - _hurd_internal_post_signal wouldn't do interrupt_operation. - After we return, our caller will set SCP->sc_intr_port (in the - new context) from SS->intr_port and clear SS->intr_port. Now - that we are restoring this old context recorded by sigreturn, - we want to restore its intr_port too; so store it in - SS->intr_port now, so it will end up in SCP->sc_intr_port - later. */ - ss->intr_port = ss->context->sc_intr_port; - } - _hurdsig_end_catch_fault (); - - /* If the sigreturn context was bogus, just ignore it. */ - ss->context = NULL; - } - else if (! machine_get_basic_state (ss->thread, state)) - return NULL; - - if ((ss->actions[signo].sa_flags & SA_ONSTACK) && - !(ss->sigaltstack.ss_flags & (SS_DISABLE|SS_ONSTACK))) - { - sigsp = ss->sigaltstack.ss_sp + ss->sigaltstack.ss_size; - ss->sigaltstack.ss_flags |= SS_ONSTACK; - /* XXX need to set up base of new stack for - per-thread variables, cthreads. */ - } - else - sigsp = (char *) state->basic.SP; - - /* Set up the sigcontext structure on the stack. This is all the stack - needs, since the args are passed in registers (below). */ - sigsp -= sizeof (*scp); - scp = sigsp; - - if (_hurdsig_catch_memory_fault (scp)) - { - /* We got a fault trying to write the stack frame. - We cannot set up the signal handler. - Returning NULL tells our caller, who will nuke us with a SIGILL. */ - return NULL; - } - else - { - /* Set up the sigcontext from the current state of the thread. */ - - scp->sc_onstack = ss->sigaltstack.ss_flags & SS_ONSTACK ? 1 : 0; - - /* struct sigcontext is laid out so that starting at sc_regs - mimics a struct alpha_thread_state. */ - memcpy (&scp->sc_alpha_thread_state, - &state->basic, sizeof (state->basic)); - - /* struct sigcontext is laid out so that starting at sc_badvaddr - mimics a struct mips_exc_state. */ - if (! machine_get_state (ss->thread, state, ALPHA_EXC_STATE, - &state->exc, &scp->sc_alpha_exc_state, - sizeof (state->exc))) - return NULL; - - if (state->exc.used_fpa && - /* struct sigcontext is laid out so that starting at sc_fpregs - mimics a struct alpha_float_state. This state - is only meaningful if the coprocessor was used. */ - ! machine_get_state (ss->thread, state, ALPHA_FLOAT_STATE, - &state->fpu, - &scp->sc_alpha_float_state, - sizeof (state->fpu))) - return NULL; - - _hurdsig_end_catch_fault (); - } - - /* Modify the thread state to call the trampoline code on the new stack. */ - if (rpc_wait) - { - /* The signalee thread was blocked in a mach_msg_trap system call, - still waiting for a reply. We will have it run the special - trampoline code which retries the message receive before running - the signal handler. - - To do this we change the OPTION argument in its registers to - enable only message reception, since the request message has - already been sent. */ - - /* The system call arguments are stored in consecutive registers - starting with a0 ($16). */ - struct mach_msg_trap_args *args = (void *) &state->basic.r16; - - assert (args->option & MACH_RCV_MSG); - /* Disable the message-send, since it has already completed. The - calls we retry need only wait to receive the reply message. */ - args->option &= ~MACH_SEND_MSG; - - /* Limit the time to receive the reply message, in case the server - claimed that `interrupt_operation' succeeded but in fact the RPC - is hung. */ - args->option |= MACH_RCV_TIMEOUT; - args->timeout = _hurd_interrupted_rpc_timeout; - - state->basic.pc = (long int) &&rpc_wait_trampoline; - /* After doing the message receive, the trampoline code will need to - update the v0 ($0) value to be restored by sigreturn. To simplify - the assembly code, we pass the address of its slot in SCP to the - trampoline code in at ($28). */ - state->basic.r28 = (long int) &scp->sc_regs[0]; - /* We must preserve the mach_msg_trap args in a0..a5 and t0 - ($16..$21, $1). Pass the handler args to the trampoline code in - t8..t10 ($22.$24). */ - state->basic.r22 = signo; - state->basic.r23 = detail->code; - state->basic.r24 = (long int) scp; - } - else - { - state->basic.pc = (long int) &&trampoline; - state->basic.r16 = signo; - state->basic.r17 = detail->code; - state->basic.r18 = (long int) scp; - } - - state->basic.r30 = (long int) sigsp; /* $30 is the stack pointer. */ - - /* We pass the handler function to the trampoline code in ra ($26). */ - state->basic.r26 = (long int) handler; - /* In the callee-saved register t12/pv ($27), we store the - address of __sigreturn itself, for the trampoline code to use. */ - state->basic.r27 = (long int) &__sigreturn; - /* In the callee-saved register t11/ai ($25), we save the SCP value to pass - to __sigreturn after the handler returns. */ - state->basic.r25 = (long int) scp; - - return scp; - - /* The trampoline code follows. This is not actually executed as part of - this function, it is just convenient to write it that way. */ - - rpc_wait_trampoline: - /* This is the entry point when we have an RPC reply message to receive - before running the handler. The MACH_MSG_SEND bit has already been - cleared in the OPTION argument in our registers. For our convenience, - at ($28) points to the sc_regs[0] member of the sigcontext (saved v0 - ($0)). */ - asm volatile - (/* Retry the interrupted mach_msg system call. */ - "lda $0, -25($31)\n" /* mach_msg_trap */ - "callsys\n" /* Magic system call instruction. */ - /* When the sigcontext was saved, v0 was MACH_RCV_INTERRUPTED. But - now the message receive has completed and the original caller of - the RPC (i.e. the code running when the signal arrived) needs to - see the final return value of the message receive in v0. So - store the new v0 value into the sc_regs[0] member of the sigcontext - (whose address is in at to make this code simpler). */ - "stq $0, 0($28)\n" - /* Since the argument registers needed to have the mach_msg_trap - arguments, we've stored the arguments to the handler function - in registers t8..t10 ($22..$24). */ - "mov $22, $16\n" - "mov $23, $17\n" - "mov $24, $18\n"); - - trampoline: - /* Entry point for running the handler normally. The arguments to the - handler function are already in the standard registers: - - a0 SIGNO - a1 SIGCODE - a2 SCP - - t12 also contains SCP; this value is callee-saved (and so should not get - clobbered by running the handler). We use this saved value to pass to - __sigreturn, so the handler can clobber the argument registers if it - likes. */ - /* Call the handler function, saving return address in ra ($26). */ - asm volatile ("jsr $26, ($26)"); - /* Reset gp ($29) from the return address (here) in ra ($26). */ - asm volatile ("ldgp $29, 0($26)"); - asm volatile ("mov $25, $16"); /* Move saved SCP to argument register. */ - /* Call __sigreturn (SCP); this cannot return. */ - asm volatile ("jmp $31, ($27)"); - - /* NOTREACHED */ - return NULL; -} |