qemu/bsd-user/aarch64/signal.c
Stacey Son ce6c541dcb bsd-user:Add AArch64 improvements and signal handling functions
Added get_ucontext_sigreturn function to check processor state ensuring current execution mode is EL0 and no flags
indicating interrupts or exceptions are set.
Updated AArch64 code to use CF directly without reading/writing the entire processor state, improving efficiency.
Changed FP data structures to use Int128 instead of __uint128_t, leveraging QEMU's generic mechanism for referencing this type.

Signed-off-by: Stacey Son <sson@FreeBSD.org>
Signed-off-by: Ajeet Singh <itachis@FreeBSD.org>
Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240707191128.10509-9-itachis@FreeBSD.org>
Signed-off-by: Warner Losh <imp@bsdimp.com>
2024-07-23 10:50:54 -06:00

138 lines
3.9 KiB
C

/*
* ARM AArch64 specific signal definitions for bsd-user
*
* Copyright (c) 2015 Stacey D. Son <sson at FreeBSD>
*
* This 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 of the License, or (at your option) any later version.
*
* This 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 this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "qemu.h"
/*
* Compare to sendsig() in sys/arm64/arm64/exec_machdep.c
* Assumes that target stack frame memory is locked.
*/
abi_long set_sigtramp_args(CPUARMState *regs, int sig,
struct target_sigframe *frame,
abi_ulong frame_addr,
struct target_sigaction *ka)
{
/*
* Arguments to signal handler:
* x0 = signal number
* x1 = siginfo pointer
* x2 = ucontext pointer
* pc/elr = signal handler pointer
* sp = sigframe struct pointer
* lr = sigtramp at base of user stack
*/
regs->xregs[0] = sig;
regs->xregs[1] = frame_addr +
offsetof(struct target_sigframe, sf_si);
regs->xregs[2] = frame_addr +
offsetof(struct target_sigframe, sf_uc);
regs->pc = ka->_sa_handler;
regs->xregs[TARGET_REG_SP] = frame_addr;
regs->xregs[TARGET_REG_LR] = TARGET_PS_STRINGS - TARGET_SZSIGCODE;
return 0;
}
/*
* Compare to get_mcontext() in arm64/arm64/machdep.c
* Assumes that the memory is locked if mcp points to user memory.
*/
abi_long get_mcontext(CPUARMState *regs, target_mcontext_t *mcp, int flags)
{
int err = 0, i;
uint64_t *gr = mcp->mc_gpregs.gp_x;
mcp->mc_gpregs.gp_spsr = pstate_read(regs);
if (flags & TARGET_MC_GET_CLEAR_RET) {
gr[0] = 0UL;
mcp->mc_gpregs.gp_spsr &= ~CPSR_C;
} else {
gr[0] = tswap64(regs->xregs[0]);
}
for (i = 1; i < 30; i++) {
gr[i] = tswap64(regs->xregs[i]);
}
mcp->mc_gpregs.gp_sp = tswap64(regs->xregs[TARGET_REG_SP]);
mcp->mc_gpregs.gp_lr = tswap64(regs->xregs[TARGET_REG_LR]);
mcp->mc_gpregs.gp_elr = tswap64(regs->pc);
/* XXX FP? */
return err;
}
/*
* Compare to arm64/arm64/exec_machdep.c sendsig()
* Assumes that the memory is locked if frame points to user memory.
*/
abi_long setup_sigframe_arch(CPUARMState *env, abi_ulong frame_addr,
struct target_sigframe *frame, int flags)
{
target_mcontext_t *mcp = &frame->sf_uc.uc_mcontext;
get_mcontext(env, mcp, flags);
return 0;
}
/*
* Compare to set_mcontext() in arm64/arm64/machdep.c
* Assumes that the memory is locked if frame points to user memory.
*/
abi_long set_mcontext(CPUARMState *regs, target_mcontext_t *mcp, int srflag)
{
int err = 0, i;
const uint64_t *gr = mcp->mc_gpregs.gp_x;
for (i = 0; i < 30; i++) {
regs->xregs[i] = tswap64(gr[i]);
}
regs->xregs[TARGET_REG_SP] = tswap64(mcp->mc_gpregs.gp_sp);
regs->xregs[TARGET_REG_LR] = tswap64(mcp->mc_gpregs.gp_lr);
regs->pc = mcp->mc_gpregs.gp_elr;
pstate_write(regs, mcp->mc_gpregs.gp_spsr);
/* XXX FP? */
return err;
}
/* Compare to sys_sigreturn() in arm64/arm64/machdep.c */
abi_long get_ucontext_sigreturn(CPUARMState *regs, abi_ulong target_sf,
abi_ulong *target_uc)
{
uint32_t pstate = pstate_read(regs);
*target_uc = 0;
if ((pstate & PSTATE_M) != PSTATE_MODE_EL0t ||
(pstate & (PSTATE_F | PSTATE_I | PSTATE_A | PSTATE_D)) != 0) {
return -TARGET_EINVAL;
}
*target_uc = target_sf;
return 0;
}