diff options
Diffstat (limited to 'sysdeps/mach/hurd/mips/sigreturn.c')
-rw-r--r-- | sysdeps/mach/hurd/mips/sigreturn.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/sysdeps/mach/hurd/mips/sigreturn.c b/sysdeps/mach/hurd/mips/sigreturn.c new file mode 100644 index 0000000000..a9f7673eb5 --- /dev/null +++ b/sysdeps/mach/hurd/mips/sigreturn.c @@ -0,0 +1,223 @@ +/* Copyright (C) 1996, 1997, 1998 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.h> +#include <hurd/signal.h> +#include <hurd/threadvar.h> +#include <stdlib.h> +#include <mach/mips/mips_instruction.h> + +int +__sigreturn (struct sigcontext *scp) +{ + struct hurd_sigstate *ss; + struct hurd_userlink *link = (void *) &scp[1]; + mach_port_t *reply_port; + + if (scp == NULL || (scp->sc_mask & _SIG_CANT_MASK)) + { + errno = EINVAL; + return -1; + } + + ss = _hurd_self_sigstate (); + __spin_lock (&ss->lock); + + /* Remove the link on the `active resources' chain added by + _hurd_setup_sighandler. Its purpose was to make sure + that we got called; now we have, it is done. */ + _hurd_userlink_unlink (link); + + /* Restore the set of blocked signals, and the intr_port slot. */ + ss->blocked = scp->sc_mask; + ss->intr_port = scp->sc_intr_port; + + /* Check for pending signals that were blocked by the old set. */ + if (ss->pending & ~ss->blocked) + { + /* There are pending signals that just became unblocked. Wake up the + signal thread to deliver them. But first, squirrel away SCP where + the signal thread will notice it if it runs another handler, and + arrange to have us called over again in the new reality. */ + ss->context = scp; + __spin_unlock (&ss->lock); + __msg_sig_post (_hurd_msgport, 0, 0, __mach_task_self ()); + /* If a pending signal was handled, sig_post never returned. */ + __spin_lock (&ss->lock); + ss->context = NULL; + } + + if (scp->sc_onstack) + { + ss->sigaltstack.ss_flags &= ~SS_ONSTACK; /* XXX threadvars */ + /* XXX cannot unlock until off sigstack */ + abort (); + } + else + __spin_unlock (&ss->lock); + + /* Destroy the MiG reply port used by the signal handler, and restore the + reply port in use by the thread when interrupted. */ + reply_port = + (mach_port_t *) __hurd_threadvar_location (_HURD_THREADVAR_MIG_REPLY); + if (*reply_port) + { + mach_port_t port = *reply_port; + + /* Assigning MACH_PORT_DEAD here tells libc's mig_get_reply_port not to + get another reply port, but avoids mig_dealloc_reply_port trying to + deallocate it after the receive fails (which it will, because the + reply port will be bogus, whether we do this or not). */ + *reply_port = MACH_PORT_DEAD; + + __mach_port_destroy (__mach_task_self (), port); + } + *reply_port = scp->sc_reply_port; + + if (scp->sc_coproc_used & SC_COPROC_USE_FPU) + { + /* Restore FPU state. */ +#define restore_fpr(n) \ + asm volatile ("l.d $f" #n ",%0" : : "m" (scp->sc_fpr[n])) + + /* Restore floating-point registers. */ +#ifdef __mips64 + restore_fpr (0); + restore_fpr (1); + restore_fpr (2); + restore_fpr (3); + restore_fpr (4); + restore_fpr (5); + restore_fpr (6); + restore_fpr (7); + restore_fpr (8); + restore_fpr (9); + restore_fpr (10); + restore_fpr (11); + restore_fpr (12); + restore_fpr (13); + restore_fpr (14); + restore_fpr (15); + restore_fpr (16); + restore_fpr (17); + restore_fpr (18); + restore_fpr (19); + restore_fpr (20); + restore_fpr (21); + restore_fpr (22); + restore_fpr (23); + restore_fpr (24); + restore_fpr (25); + restore_fpr (26); + restore_fpr (27); + restore_fpr (28); + restore_fpr (29); + restore_fpr (30); + restore_fpr (31); +#else + restore_fpr (0); + restore_fpr (2); + restore_fpr (4); + restore_fpr (6); + restore_fpr (8); + restore_fpr (10); + restore_fpr (12); + restore_fpr (14); + restore_fpr (16); + restore_fpr (18); + restore_fpr (20); + restore_fpr (22); + restore_fpr (24); + restore_fpr (26); + restore_fpr (28); + restore_fpr (30); +#endif + + /* Restore the floating-point control/status register ($f31). */ + asm volatile ("ctc1 %0,$f31" : : "r" (scp->sc_fpcsr)); + } + + /* Load all the registers from the sigcontext. */ +#ifdef __mips64 +#define restore_gpr(n) \ + asm volatile ("ld $" #n ",%0" : : "m" (scpreg->sc_gpr[n - 1])) +#else +#define restore_gpr(n) \ + asm volatile ("lw $" #n ",%0" : : "m" (scpreg->sc_gpr[n - 1])) +#endif + + { + register const struct sigcontext *const scpreg asm ("$1") = scp; + register int *at asm ("$1"); + + /* First restore the multiplication result registers. The compiler + will use some temporary registers, so we do this before restoring + the general registers. */ + asm volatile ("mtlo %0" : : "r" (scpreg->sc_mdlo)); + asm volatile ("mthi %0" : : "r" (scpreg->sc_mdhi)); + + /* In the word after the saved PC, store the saved $1 value. */ + (&scpreg->sc_pc)[1] = scpreg->sc_gpr[0]; + + asm volatile (".set noreorder; .set noat;"); + + /* Restore the normal registers. */ + restore_gpr (2); + restore_gpr (3); + restore_gpr (4); + restore_gpr (5); + restore_gpr (6); + restore_gpr (7); + restore_gpr (8); + restore_gpr (9); + restore_gpr (10); + restore_gpr (11); + restore_gpr (12); + restore_gpr (13); + restore_gpr (14); + restore_gpr (15); + restore_gpr (16); + restore_gpr (17); + restore_gpr (18); + restore_gpr (19); + restore_gpr (20); + restore_gpr (21); + restore_gpr (22); + restore_gpr (23); + restore_gpr (24); + restore_gpr (25); + /* Registers 26-27 are kernel-only. */ + restore_gpr (28); + restore_gpr (29); /* Stack pointer. */ + restore_gpr (30); /* Frame pointer. */ + restore_gpr (31); /* Return address. */ + + at = &scpreg->sc_pc; + /* This is an emulated instruction that will find at the address in $1 + two words: the PC value to restore, and the $1 value to restore. */ + asm volatile (".word %0" : : "i" (op_sigreturn)); + asm volatile (".set reorder; .set at;"); + /* NOTREACHED */ + return at; /* To prevent optimization. */ + } + + /* NOTREACHED */ + return -1; +} + +weak_alias (__sigreturn, sigreturn) |