aboutsummaryrefslogtreecommitdiff
path: root/sysdeps/mach/hurd/mips/trampoline.c
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/mach/hurd/mips/trampoline.c')
-rw-r--r--sysdeps/mach/hurd/mips/trampoline.c292
1 files changed, 0 insertions, 292 deletions
diff --git a/sysdeps/mach/hurd/mips/trampoline.c b/sysdeps/mach/hurd/mips/trampoline.c
deleted file mode 100644
index 34e363b1aa..0000000000
--- a/sysdeps/mach/hurd/mips/trampoline.c
+++ /dev/null
@@ -1,292 +0,0 @@
-/* Set thread_state for sighandler, and sigcontext to recover. MIPS version.
- Copyright (C) 1996, 1997, 1998, 2005 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 <hurd/userlink.h>
-#include <thread_state.h>
-#include <assert.h>
-#include <errno.h>
-#include "hurdfault.h"
-#include <intr-msg.h>
-
-
-struct sigcontext *
-_hurd_setup_sighandler (struct hurd_sigstate *ss, __sighandler_t handler,
- int signo, struct hurd_signal_detail *detail,
- volatile int rpc_wait,
- struct machine_thread_all_state *state)
-{
- __label__ trampoline, rpc_wait_trampoline, firewall;
- void *volatile sigsp;
- struct sigcontext *scp;
- struct
- {
- int signo;
- long int sigcode;
- struct sigcontext *scp; /* Points to ctx, below. */
- void *sigreturn_addr;
- void *sigreturn_returns_here;
- struct sigcontext *return_scp; /* Same; arg to sigreturn. */
- struct sigcontext ctx;
- struct hurd_userlink link;
- } *stackframe;
-
- 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_mips_thread_state,
- sizeof (state->basic));
- memcpy (&state->exc, &ss->context->sc_mips_exc_state,
- sizeof (state->exc));
- state->set = (1 << MIPS_THREAD_STATE) | (1 << MIPS_EXC_STATE);
- if (state->exc.coproc_state & SC_COPROC_USE_FPU)
- {
- memcpy (&state->fpu, &ss->context->sc_mips_float_state,
- sizeof (state->fpu));
- state->set |= (1 << MIPS_FLOAT_STATE);
- }
- }
- }
-
- if (! machine_get_basic_state (ss->thread, state))
- return NULL;
-
- /* Save the original SP in the gratuitous s0 ($16) slot.
- We may need to reset the SP (the `r29' slot) to avoid clobbering an
- interrupted RPC frame. */
- state->basic.r16 = state->basic.r29;
-
- 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.r29;
-
- /* Push the arguments to call `trampoline' on the stack. */
- sigsp -= sizeof (*stackframe);
- stackframe = sigsp;
-
- if (_hurdsig_catch_memory_fault (stackframe))
- {
- /* 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
- {
- int ok;
-
- extern void _hurdsig_longjmp_from_handler (void *, jmp_buf, int);
-
- /* Add a link to the thread's active-resources list. We mark this as
- the only user of the "resource", so the cleanup function will be
- called by any longjmp which is unwinding past the signal frame.
- The cleanup function (in sigunwind.c) will make sure that all the
- appropriate cleanups done by sigreturn are taken care of. */
- stackframe->link.cleanup = &_hurdsig_longjmp_from_handler;
- stackframe->link.cleanup_data = &stackframe->ctx;
- stackframe->link.resource.next = NULL;
- stackframe->link.resource.prevp = NULL;
- stackframe->link.thread.next = ss->active_resources;
- stackframe->link.thread.prevp = &ss->active_resources;
- if (stackframe->link.thread.next)
- stackframe->link.thread.next->thread.prevp
- = &stackframe->link.thread.next;
- ss->active_resources = &stackframe->link;
-
- /* Set up the arguments for the signal handler. */
- stackframe->signo = signo;
- stackframe->sigcode = detail->code;
- stackframe->scp = stackframe->return_scp = scp = &stackframe->ctx;
- stackframe->sigreturn_addr = &__sigreturn;
- stackframe->sigreturn_returns_here = &&firewall; /* Crash on return. */
-
- /* 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_gpr
- mimics a struct mips_thread_state. */
- memcpy (&scp->sc_mips_thread_state,
- &state->basic, sizeof (state->basic));
-
- /* struct sigcontext is laid out so that starting at sc_cause
- mimics a struct mips_exc_state. */
- ok = machine_get_state (ss->thread, state, MIPS_EXC_STATE,
- &state->exc, &scp->sc_cause,
- sizeof (state->exc));
-
- if (ok && (scp->sc_coproc_used & SC_COPROC_USE_FPU))
- /* struct sigcontext is laid out so that starting at sc_fpr
- mimics a struct mips_float_state. This state
- is only meaningful if the coprocessor was used. */
- ok = machine_get_state (ss->thread, state, MIPS_FLOAT_STATE,
- &state->fpu, &scp->sc_mips_float_state,
- sizeof (state->fpu));
-
- _hurdsig_end_catch_fault ();
-
- if (! ok)
- return NULL;
- }
-
- /* 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 ($4). */
- struct mach_msg_trap_args *args = (void *) &state->basic.r4;
-
- if (_hurdsig_catch_memory_fault (args))
- {
- /* Faulted accessing ARGS. Bomb. */
- return NULL;
- }
-
- 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;
-
- _hurdsig_end_catch_fault ();
-
- state->basic.pc = (int) &&rpc_wait_trampoline;
- /* The reply-receiving trampoline code runs initially on the original
- user stack. We pass it the signal stack pointer in s4 ($20). */
- state->basic.r29 = state->basic.r16; /* Restore mach_msg syscall SP. */
- state->basic.r20 = (int) sigsp;
- /* After doing the message receive, the trampoline code will need to
- update the v0 ($2) 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 s5 ($21). */
- state->basic.r21 = (int) &scp->sc_gpr[1];
- /* We must preserve the mach_msg_trap args in a0..t2 ($4..$10).
- Pass the handler args to the trampoline code in s1..s3 ($17..$19). */
- state->basic.r17 = signo;
- state->basic.r18 = detail->code;
- state->basic.r19 = (int) scp;
- }
- else
- {
- state->basic.pc = (int) &&trampoline;
- state->basic.r29 = (int) sigsp;
- state->basic.r4 = signo;
- state->basic.r5 = detail->code;
- state->basic.r6 = (int) scp;
- }
-
- /* We pass the handler function to the trampoline code in s6 ($22). */
- state->basic.r22 = (int) handler;
- /* In the callee-saved register s0 ($16), we save the SCP value to pass
- to __sigreturn after the handler returns. */
- state->basic.r16 = (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,
- $3 points to the sc_gpr[1] member of the sigcontext (saved v0 ($2)). */
- asm volatile
- (".set noat; .set noreorder; .set nomacro\n"
- /* Retry the interrupted mach_msg system call. */
-#ifdef __mips64
- "dli $2, -25\n" /* mach_msg_trap */
-#else
- "li $2, -25\n" /* mach_msg_trap */
-#endif
- "syscall\n"
- /* 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_gpr[1] member of the sigcontext
- (whose address is in s5 to make this code simpler). */
-#ifdef __mips64
- "sd $2, ($21)\n"
-#else
- "sw $2, ($21)\n"
-#endif
- /* Since the argument registers needed to have the mach_msg_trap
- arguments, we've stored the arguments to the handler function
- in registers s1..s3 ($17..$19). */
- "move $4, $17\n"
- "move $5, $18\n"
- "move $6, $19\n"
- /* Switch to the signal stack. */
- "move $29, $20\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
- */
- asm volatile
- ("move $25, $22\n" /* Copy s6 to t9 for MIPS ABI. */
- "jal $25; nop\n" /* Call the handler function. */
- /* Call __sigreturn (SCP); this cannot return. */
-#ifdef __mips64
- "dla $1,%0\n"
-#else
- "la $1,%0\n"
-#endif
- "j $1\n"
- "move $4, $16" /* Set up arg from saved SCP in delay slot. */
- : : "i" (&__sigreturn));
-
- /* NOTREACHED */
- asm volatile (".set reorder; .set at; .set macro");
-
- firewall:
- asm volatile ("hlt: j hlt");
-
- return NULL;
-}