From 007f5c35895786fdc797f13313b9493fe5d5e655 Mon Sep 17 00:00:00 2001 From: Alan Kao Date: Tue, 9 Oct 2018 10:18:31 +0800 Subject: [PATCH] Refactor FPU code in signal setup/return procedures FPU-related logic is separated from normal signal handling path in this patch. Kernel can easily be configured to exclude those procedures for no-FPU systems. Signed-off-by: Alan Kao Cc: Greentime Hu Cc: Vincent Chen Cc: Zong Li Cc: Nick Hu Reviewed-by: Christoph Hellwig Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/signal.c | 68 ++++++++++++++++++++++++++++------------------ 1 file changed, 41 insertions(+), 27 deletions(-) diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c index 718d0c9..6a18b98 100644 --- a/arch/riscv/kernel/signal.c +++ b/arch/riscv/kernel/signal.c @@ -37,45 +37,63 @@ struct rt_sigframe { struct ucontext uc; }; -static long restore_d_state(struct pt_regs *regs, - struct __riscv_d_ext_state __user *state) +static long restore_fp_state(struct pt_regs *regs, + union __riscv_fp_state *sc_fpregs) { long err; + struct __riscv_d_ext_state __user *state = &sc_fpregs->d; + size_t i; + err = __copy_from_user(¤t->thread.fstate, state, sizeof(*state)); - if (likely(!err)) - fstate_restore(current, regs); + if (unlikely(err)) + return err; + + fstate_restore(current, regs); + + /* We support no other extension state at this time. */ + for (i = 0; i < ARRAY_SIZE(sc_fpregs->q.reserved); i++) { + u32 value; + + err = __get_user(value, &sc_fpregs->q.reserved[i]); + if (unlikely(err)) + break; + if (value != 0) + return -EINVAL; + } + return err; } -static long save_d_state(struct pt_regs *regs, - struct __riscv_d_ext_state __user *state) +static long save_fp_state(struct pt_regs *regs, + union __riscv_fp_state *sc_fpregs) { + long err; + struct __riscv_d_ext_state __user *state = &sc_fpregs->d; + size_t i; + fstate_save(current, regs); - return __copy_to_user(state, ¤t->thread.fstate, sizeof(*state)); + err = __copy_to_user(state, ¤t->thread.fstate, sizeof(*state)); + if (unlikely(err)) + return err; + + /* We support no other extension state at this time. */ + for (i = 0; i < ARRAY_SIZE(sc_fpregs->q.reserved); i++) { + err = __put_user(0, &sc_fpregs->q.reserved[i]); + if (unlikely(err)) + break; + } + + return err; } static long restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) { long err; - size_t i; /* sc_regs is structured the same as the start of pt_regs */ err = __copy_from_user(regs, &sc->sc_regs, sizeof(sc->sc_regs)); - if (unlikely(err)) - return err; /* Restore the floating-point state. */ - err = restore_d_state(regs, &sc->sc_fpregs.d); - if (unlikely(err)) - return err; - /* We support no other extension state at this time. */ - for (i = 0; i < ARRAY_SIZE(sc->sc_fpregs.q.reserved); i++) { - u32 value; - err = __get_user(value, &sc->sc_fpregs.q.reserved[i]); - if (unlikely(err)) - break; - if (value != 0) - return -EINVAL; - } + err |= restore_fp_state(regs, &sc->sc_fpregs); return err; } @@ -124,14 +142,10 @@ static long setup_sigcontext(struct rt_sigframe __user *frame, { struct sigcontext __user *sc = &frame->uc.uc_mcontext; long err; - size_t i; /* sc_regs is structured the same as the start of pt_regs */ err = __copy_to_user(&sc->sc_regs, regs, sizeof(sc->sc_regs)); /* Save the floating-point state. */ - err |= save_d_state(regs, &sc->sc_fpregs.d); - /* We support no other extension state at this time. */ - for (i = 0; i < ARRAY_SIZE(sc->sc_fpregs.q.reserved); i++) - err |= __put_user(0, &sc->sc_fpregs.q.reserved[i]); + err |= save_fp_state(regs, &sc->sc_fpregs); return err; } -- 2.7.4