Marc Zyngier <marc.zyng...@arm.com> writes:

> Implement the debug save restore as a direct translation of
> the assembly code version.
>
> Signed-off-by: Marc Zyngier <marc.zyng...@arm.com>
> ---
>  arch/arm64/kvm/hyp/Makefile   |   1 +
>  arch/arm64/kvm/hyp/debug-sr.c | 130 
> ++++++++++++++++++++++++++++++++++++++++++
>  arch/arm64/kvm/hyp/hyp.h      |   9 +++
>  3 files changed, 140 insertions(+)
>  create mode 100644 arch/arm64/kvm/hyp/debug-sr.c
>
> diff --git a/arch/arm64/kvm/hyp/Makefile b/arch/arm64/kvm/hyp/Makefile
> index ec94200..ec14cac 100644
> --- a/arch/arm64/kvm/hyp/Makefile
> +++ b/arch/arm64/kvm/hyp/Makefile
> @@ -6,3 +6,4 @@ obj-$(CONFIG_KVM_ARM_HOST) += vgic-v2-sr.o
>  obj-$(CONFIG_KVM_ARM_HOST) += vgic-v3-sr.o
>  obj-$(CONFIG_KVM_ARM_HOST) += timer-sr.o
>  obj-$(CONFIG_KVM_ARM_HOST) += sysreg-sr.o
> +obj-$(CONFIG_KVM_ARM_HOST) += debug-sr.o
> diff --git a/arch/arm64/kvm/hyp/debug-sr.c b/arch/arm64/kvm/hyp/debug-sr.c
> new file mode 100644
> index 0000000..a0b2b99
> --- /dev/null
> +++ b/arch/arm64/kvm/hyp/debug-sr.c
> @@ -0,0 +1,130 @@
> +/*
> + * Copyright (C) 2015 - ARM Ltd
> + * Author: Marc Zyngier <marc.zyng...@arm.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * 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 <linux/compiler.h>
> +#include <linux/kvm_host.h>
> +
> +#include <asm/kvm_mmu.h>
> +
> +#include "hyp.h"
> +
> +#define read_debug(r,n)              read_sysreg(r##n##_el1)
> +#define write_debug(v,r,n)   write_sysreg(v, r##n##_el1)
> +
> +#define save_debug(ptr,reg,nr)                                               
> \
> +     switch (nr) {                                                   \
> +     case 15:        ptr[15] = read_debug(reg, 15);                  \
> +     case 14:        ptr[14] = read_debug(reg, 14);                  \
> +     case 13:        ptr[13] = read_debug(reg, 13);                  \
> +     case 12:        ptr[12] = read_debug(reg, 12);                  \
> +     case 11:        ptr[11] = read_debug(reg, 11);                  \
> +     case 10:        ptr[10] = read_debug(reg, 10);                  \
> +     case 9:         ptr[9] = read_debug(reg, 9);                    \
> +     case 8:         ptr[8] = read_debug(reg, 8);                    \
> +     case 7:         ptr[7] = read_debug(reg, 7);                    \
> +     case 6:         ptr[6] = read_debug(reg, 6);                    \
> +     case 5:         ptr[5] = read_debug(reg, 5);                    \
> +     case 4:         ptr[4] = read_debug(reg, 4);                    \
> +     case 3:         ptr[3] = read_debug(reg, 3);                    \
> +     case 2:         ptr[2] = read_debug(reg, 2);                    \
> +     case 1:         ptr[1] = read_debug(reg, 1);                    \
> +     default:        ptr[0] = read_debug(reg, 0);                    \
> +     }
> +
> +#define restore_debug(ptr,reg,nr)                                    \
> +     switch (nr) {                                                   \
> +     case 15:        write_debug(ptr[15], reg, 15);                  \
> +     case 14:        write_debug(ptr[14], reg, 14);                  \
> +     case 13:        write_debug(ptr[13], reg, 13);                  \
> +     case 12:        write_debug(ptr[12], reg, 12);                  \
> +     case 11:        write_debug(ptr[11], reg, 11);                  \
> +     case 10:        write_debug(ptr[10], reg, 10);                  \
> +     case 9:         write_debug(ptr[9], reg, 9);                    \
> +     case 8:         write_debug(ptr[8], reg, 8);                    \
> +     case 7:         write_debug(ptr[7], reg, 7);                    \
> +     case 6:         write_debug(ptr[6], reg, 6);                    \
> +     case 5:         write_debug(ptr[5], reg, 5);                    \
> +     case 4:         write_debug(ptr[4], reg, 4);                    \
> +     case 3:         write_debug(ptr[3], reg, 3);                    \
> +     case 2:         write_debug(ptr[2], reg, 2);                    \
> +     case 1:         write_debug(ptr[1], reg, 1);                    \
> +     default:        write_debug(ptr[0], reg, 0);                    \
> +     }
> +
> +void __hyp_text __debug_save_state(struct kvm_vcpu *vcpu,
> +                                struct kvm_guest_debug_arch *dbg,
> +                                struct kvm_cpu_context *ctxt)
> +{
> +     if (vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY) {
> +             u64 aa64dfr0 = read_sysreg(id_aa64dfr0_el1);
> +             int brps, wrps;
> +
> +             brps = (aa64dfr0 >> 12) & 0xf;
> +             wrps = (aa64dfr0 >> 20) & 0xf;

I'm sure we have that defined - get_num_brps/wrps() - but I don't know
if the compiler would do a better job with it.

> +
> +             save_debug(dbg->dbg_bcr, dbgbcr, brps);
> +             save_debug(dbg->dbg_bvr, dbgbvr, brps);
> +             save_debug(dbg->dbg_wcr, dbgwcr, wrps);
> +             save_debug(dbg->dbg_wvr, dbgwvr, wrps);
> +
> +             ctxt->sys_regs[MDCCINT_EL1] = read_sysreg(mdccint_el1);
> +     }
> +}
> +
> +void __hyp_text __debug_restore_state(struct kvm_vcpu *vcpu,
> +                                   struct kvm_guest_debug_arch *dbg,
> +                                   struct kvm_cpu_context *ctxt)
> +{
> +     if (vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY) {
> +             u64 aa64dfr0 = read_sysreg(id_aa64dfr0_el1);
> +             int brps, wrps;
> +
> +             brps = (aa64dfr0 >> 12) & 0xf;
> +             wrps = (aa64dfr0 >> 20) & 0xf;
> +
> +             restore_debug(dbg->dbg_bcr, dbgbcr, brps);
> +             restore_debug(dbg->dbg_bvr, dbgbvr, brps);
> +             restore_debug(dbg->dbg_wcr, dbgwcr, wrps);
> +             restore_debug(dbg->dbg_wvr, dbgwvr, wrps);
> +
> +             write_sysreg(ctxt->sys_regs[MDCCINT_EL1], mdccint_el1);
> +     }
> +}
> +
> +void __hyp_text __debug_cond_save_host_state(struct kvm_vcpu *vcpu)
> +{
> +     if ((vcpu->arch.ctxt.sys_regs[MDSCR_EL1] & DBG_MDSCR_KDE) ||
> +         (vcpu->arch.ctxt.sys_regs[MDSCR_EL1] & DBG_MDSCR_KDE))
> +             vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY;
> +
> +     __debug_save_state(vcpu, &vcpu->arch.host_debug_state,
> +                        kern_hyp_va(vcpu->arch.host_cpu_context));
> +}
> +
> +void __hyp_text __debug_cond_restore_host_state(struct kvm_vcpu *vcpu)
> +{
> +     if (vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY) {
> +             __debug_restore_state(vcpu, &vcpu->arch.host_debug_state,
> +                                   kern_hyp_va(vcpu->arch.host_cpu_context));
> +             vcpu->arch.debug_flags &= ~KVM_ARM64_DEBUG_DIRTY;
> +     }
> +}
> +
> +u32 __hyp_text __debug_read_mdcr_el2(void)
> +{
> +     return read_sysreg(mdcr_el2);
> +}
> diff --git a/arch/arm64/kvm/hyp/hyp.h b/arch/arm64/kvm/hyp/hyp.h
> index 4639330..2581232 100644
> --- a/arch/arm64/kvm/hyp/hyp.h
> +++ b/arch/arm64/kvm/hyp/hyp.h
> @@ -41,5 +41,14 @@ void __sysreg_restore_state(struct kvm_cpu_context *ctxt);
>  void __sysreg32_save_state(struct kvm_vcpu *vcpu);
>  void __sysreg32_restore_state(struct kvm_vcpu *vcpu);
>
> +void __debug_save_state(struct kvm_vcpu *vcpu,
> +                     struct kvm_guest_debug_arch *dbg,
> +                     struct kvm_cpu_context *ctxt);
> +void __debug_restore_state(struct kvm_vcpu *vcpu,
> +                        struct kvm_guest_debug_arch *dbg,
> +                        struct kvm_cpu_context *ctxt);
> +void __debug_cond_save_host_state(struct kvm_vcpu *vcpu);
> +void __debug_cond_restore_host_state(struct kvm_vcpu *vcpu);
> +
>  #endif /* __ARM64_KVM_HYP_H__ */

I spun it up against my KVM debug tests and everything was fine. Have a:

Tested-by: Alex Bennée <alex.ben...@linaro.org>
Reviewed-by: Alex Bennée <alex.ben...@linaro.org>


--
Alex Bennée
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to