linux-user/ppc: Implement setup_sigtramp

Create and record the two signal trampolines.

Cc: qemu-ppc@nongnu.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210929130553.121567-20-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
This commit is contained in:
Richard Henderson 2021-09-29 09:05:46 -04:00 committed by Laurent Vivier
parent 5d2fc70f57
commit c790e4ebfe
2 changed files with 20 additions and 16 deletions

View File

@ -203,9 +203,6 @@ struct target_func_ptr {
#endif
/* We use the mc_pad field for the signal return trampoline. */
#define tramp mc_pad
/* See arch/powerpc/kernel/signal.c. */
static target_ulong get_sigframe(struct target_sigaction *ka,
CPUPPCState *env,
@ -436,12 +433,7 @@ void setup_frame(int sig, struct target_sigaction *ka,
/* Save user regs. */
save_user_regs(env, &frame->mctx);
/* Construct the trampoline code on the stack. */
encode_trampoline(TARGET_NR_sigreturn, (uint32_t *)&frame->mctx.tramp);
/* The kernel checks for the presence of a VDSO here. We don't
emulate a vdso, so use a sigreturn system call. */
env->lr = (target_ulong) h2g(frame->mctx.tramp);
env->lr = default_sigreturn;
/* Turn off all fp exceptions. */
env->fpscr = 0;
@ -477,7 +469,6 @@ void setup_rt_frame(int sig, struct target_sigaction *ka,
target_sigset_t *set, CPUPPCState *env)
{
struct target_rt_sigframe *rt_sf;
uint32_t *trampptr = 0;
struct target_mcontext *mctx = 0;
target_ulong rt_sf_addr, newsp = 0;
int i, err = 0;
@ -507,22 +498,17 @@ void setup_rt_frame(int sig, struct target_sigaction *ka,
#if defined(TARGET_PPC64)
mctx = &rt_sf->uc.tuc_sigcontext.mcontext;
trampptr = &rt_sf->trampoline[0];
sc = &rt_sf->uc.tuc_sigcontext;
__put_user(h2g(mctx), &sc->regs);
__put_user(sig, &sc->signal);
#else
mctx = &rt_sf->uc.tuc_mcontext;
trampptr = (uint32_t *)&rt_sf->uc.tuc_mcontext.tramp;
#endif
save_user_regs(env, mctx);
encode_trampoline(TARGET_NR_rt_sigreturn, trampptr);
/* The kernel checks for the presence of a VDSO here. We don't
emulate a vdso, so use a sigreturn system call. */
env->lr = (target_ulong) h2g(trampptr);
env->lr = default_rt_sigreturn;
/* Turn off all fp exceptions. */
env->fpscr = 0;
@ -720,3 +706,19 @@ abi_long do_swapcontext(CPUArchState *env, abi_ulong uold_ctx,
return 0;
}
void setup_sigtramp(abi_ulong sigtramp_page)
{
uint32_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 2 * 8, 0);
assert(tramp != NULL);
#ifdef TARGET_ARCH_HAS_SETUP_FRAME
default_sigreturn = sigtramp_page;
encode_trampoline(TARGET_NR_sigreturn, tramp + 0);
#endif
default_rt_sigreturn = sigtramp_page + 8;
encode_trampoline(TARGET_NR_rt_sigreturn, tramp + 2);
unlock_user(tramp, sigtramp_page, 2 * 8);
}

View File

@ -24,4 +24,6 @@ typedef struct target_sigaltstack {
#if !defined(TARGET_PPC64)
#define TARGET_ARCH_HAS_SETUP_FRAME
#endif
#define TARGET_ARCH_HAS_SIGTRAMP_PAGE 1
#endif /* PPC_TARGET_SIGNAL_H */