On Fri, Aug 2, 2024 at 7:46 AM Richard Henderson <
richard.henderson@linaro.org> wrote:
> On 8/2/24 18:34, Ajeet Singh wrote:
> > From: Mark Corbin <mark.corbin@embecsom.com>
> >
> > Added functions for setting up the RISC-V signal trampoline and signal
> > frame:
> >
> > 'set_sigtramp_args()': Configures the RISC-V CPU state with arguments
> > for the signal handler. It sets up the registers with the signal
> > number,pointers to the signal info and user context, the signal handler
> > address, and the signal frame pointer.
> >
> > 'setup_sigframe_arch()': Initializes the signal frame with the current
> > machine context.This function copies the context from the CPU state to
> > the signal frame, preparing it for the signal handler.
> >
> > Signed-off-by: Mark Corbin <mark.corbin@embecsom.com>
> > Signed-off-by: Ajeet Singh <itachis@FreeBSD.org>
> > Signed-off-by: Warner Losh <imp@bsdimp.com>
> > Co-authored-by: Warner Losh <imp@bsdimp.com>
> > ---
> > bsd-user/riscv/signal.c | 63 +++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 63 insertions(+)
> > create mode 100644 bsd-user/riscv/signal.c
> >
> > diff --git a/bsd-user/riscv/signal.c b/bsd-user/riscv/signal.c
> > new file mode 100644
> > index 0000000000..005eb53cab
> > --- /dev/null
> > +++ b/bsd-user/riscv/signal.c
> > @@ -0,0 +1,63 @@
> > +/*
> > + * RISC-V signal definitions
> > + *
> > + * Copyright (c) 2019 Mark Corbin
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License as published by
> > + * the Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + *
> > + * This program 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 General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU General Public License
> > + * along with this program; if not, see <http://www.gnu.org/licenses/
> >.
> > + */
> > +#include "qemu/osdep.h"
> > +
> > +#include "qemu.h"
> > +
> > +/*
> > + * Compare with sendsig() in riscv/riscv/exec_machdep.c
> > + * Assumes that target stack frame memory is locked.
> > + */
> > +abi_long
> > +set_sigtramp_args(CPURISCVState *regs, int sig, struct target_sigframe
> *frame,
> > + abi_ulong frame_addr, struct target_sigaction *ka)
> > +{
> > + /*
> > + * Arguments to signal handler:
> > + * a0 (10) = signal number
> > + * a1 (11) = siginfo pointer
> > + * a2 (12) = ucontext pointer
> > + * pc = signal pointer handler
> > + * sp (2) = sigframe pointer
> > + * ra (1) = sigtramp at base of user stack
> > + */
> > +
> > + regs->gpr[10] = sig;
> > + regs->gpr[11] = frame_addr +
> > + offsetof(struct target_sigframe, sf_si);
> > + regs->gpr[12] = frame_addr +
> > + offsetof(struct target_sigframe, sf_uc);
>
> xA0 .. xA2
>
> > + regs->pc = ka->_sa_handler;
> > + regs->gpr[2] = frame_addr;
> > + regs->gpr[1] = TARGET_PS_STRINGS - TARGET_SZSIGCODE;
>
> xRA, xSP.
>
So to be clear, this is 'use these constants rather than the raw numbers
for the array subscripts' right?
Warner
Otherwise,
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
>
> r~
>