[PATCH v2 09/19] KVM: arm64: Move vcpu debug/SPE/TRBE flags to the input flag set

Marc Zyngier
2022-06-10T09:30:45Z

The three debug flags (which deal with the debug registers, SPE and
TRBE) all are input flags to the hypervisor code.

Move them into the input set and convert them to the new accessors.

Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/include/asm/kvm_host.h | 9 +++++---
arch/arm64/kvm/debug.c | 25 +++++++++++-----------
arch/arm64/kvm/hyp/include/hyp/debug-sr.h | 6 +++---
arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 4 ++--
arch/arm64/kvm/hyp/nvhe/debug-sr.c | 8 +++----
arch/arm64/kvm/sys_regs.c | 8 +++----
6 files changed, 31 insertions(+), 29 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index db42b4c06449..4c7446400b77 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -508,6 +508,12 @@ struct kvm_vcpu_arch {
#define EXCEPT_AA64_EL2_IRQ __vcpu_except_flags(5)
#define EXCEPT_AA64_EL2_FIQ __vcpu_except_flags(6)
#define EXCEPT_AA64_EL2_SERR __vcpu_except_flags(7)
+/* Guest debug is live */
+#define DEBUG_DIRTY __vcpu_single_flag(iflags, BIT(4))
+/* Save SPE context if active */
+#define DEBUG_STATE_SAVE_SPE __vcpu_single_flag(iflags, BIT(5))
+/* Save TRBE context if active */
+#define DEBUG_STATE_SAVE_TRBE __vcpu_single_flag(iflags, BIT(6))

/* Pointer to the vcpu's SVE FFR for sve_{save,load}_state() */
#define vcpu_sve_pffr(vcpu) (kern_hyp_va((vcpu)->arch.sve_state) + \
@@ -530,10 +536,7 @@ struct kvm_vcpu_arch {
})

/* vcpu_arch flags field values: */
-#define KVM_ARM64_DEBUG_DIRTY (1 << 0)
#define KVM_ARM64_HOST_SVE_ENABLED (1 << 4) /* SVE enabled for EL0 */
-#define KVM_ARM64_DEBUG_STATE_SAVE_SPE (1 << 12) /* Save SPE context if active */
-#define KVM_ARM64_DEBUG_STATE_SAVE_TRBE (1 << 13) /* Save TRBE context if active */
#define KVM_ARM64_ON_UNSUPPORTED_CPU (1 << 15) /* Physical CPU not in supported_cpus */
#define KVM_ARM64_HOST_SME_ENABLED (1 << 16) /* SME enabled for EL0 */
#define KVM_ARM64_WFIT (1 << 17) /* WFIT instruction trapped */
diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c
index 4fd5c216c4bb..0b28d7db7c76 100644
--- a/arch/arm64/kvm/debug.c
+++ b/arch/arm64/kvm/debug.c
@@ -104,11 +104,11 @@ static void kvm_arm_setup_mdcr_el2(struct kvm_vcpu *vcpu)
* Trap debug register access when one of the following is true:
* - Userspace is using the hardware to debug the guest
* (KVM_GUESTDBG_USE_HW is set).
- * - The guest is not using debug (KVM_ARM64_DEBUG_DIRTY is clear).
+ * - The guest is not using debug (DEBUG_DIRTY clear).
* - The guest has enabled the OS Lock (debug exceptions are blocked).
*/
if ((vcpu->guest_debug & KVM_GUESTDBG_USE_HW) ||
- !(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY) ||
+ !vcpu_get_flag(vcpu, DEBUG_DIRTY) ||
kvm_vcpu_os_lock_enabled(vcpu))
vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA;

@@ -147,8 +147,8 @@ void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu)
* debug related registers.
*
* Additionally, KVM only traps guest accesses to the debug registers if
- * the guest is not actively using them (see the KVM_ARM64_DEBUG_DIRTY
- * flag on vcpu->arch.flags). Since the guest must not interfere
+ * the guest is not actively using them (see the DEBUG_DIRTY
+ * flag on vcpu->arch.iflags). Since the guest must not interfere
* with the hardware state when debugging the guest, we must ensure that
* trapping is enabled whenever we are debugging the guest using the
* debug registers.
@@ -205,9 +205,8 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu)
*
* We simply switch the debug_ptr to point to our new
* external_debug_state which has been populated by the
- * debug ioctl. The existing KVM_ARM64_DEBUG_DIRTY
- * mechanism ensures the registers are updated on the
- * world switch.
+ * debug ioctl. The existing DEBUG_DIRTY mechanism ensures
+ * the registers are updated on the world switch.
*/
if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) {
/* Enable breakpoints/watchpoints */
@@ -216,7 +215,7 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu)
vcpu_write_sys_reg(vcpu, mdscr, MDSCR_EL1);

vcpu->arch.debug_ptr = &vcpu->arch.external_debug_state;
- vcpu->arch.flags |= KVM_ARM64_DEBUG_DIRTY;
+ vcpu_set_flag(vcpu, DEBUG_DIRTY);

trace_kvm_arm_set_regset("BKPTS", get_num_brps(),
&vcpu->arch.debug_ptr->dbg_bcr[0],
@@ -246,7 +245,7 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu)

/* If KDE or MDE are set, perform a full save/restore cycle. */
if (vcpu_read_sys_reg(vcpu, MDSCR_EL1) & (DBG_MDSCR_KDE | DBG_MDSCR_MDE))
- vcpu->arch.flags |= KVM_ARM64_DEBUG_DIRTY;
+ vcpu_set_flag(vcpu, DEBUG_DIRTY);

/* Write mdcr_el2 changes since vcpu_load on VHE systems */
if (has_vhe() && orig_mdcr_el2 != vcpu->arch.mdcr_el2)
@@ -298,16 +297,16 @@ void kvm_arch_vcpu_load_debug_state_flags(struct kvm_vcpu *vcpu)
*/
if (cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_PMSVER_SHIFT) &&
!(read_sysreg_s(SYS_PMBIDR_EL1) & BIT(SYS_PMBIDR_EL1_P_SHIFT)))
- vcpu->arch.flags |= KVM_ARM64_DEBUG_STATE_SAVE_SPE;
+ vcpu_set_flag(vcpu, DEBUG_STATE_SAVE_SPE);

/* Check if we have TRBE implemented and available at the host */
if (cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_TRBE_SHIFT) &&
!(read_sysreg_s(SYS_TRBIDR_EL1) & TRBIDR_PROG))
- vcpu->arch.flags |= KVM_ARM64_DEBUG_STATE_SAVE_TRBE;
+ vcpu_set_flag(vcpu, DEBUG_STATE_SAVE_TRBE);
}

void kvm_arch_vcpu_put_debug_state_flags(struct kvm_vcpu *vcpu)
{
- vcpu->arch.flags &= ~(KVM_ARM64_DEBUG_STATE_SAVE_SPE |
- KVM_ARM64_DEBUG_STATE_SAVE_TRBE);
+ vcpu_clear_flag(vcpu, DEBUG_STATE_SAVE_SPE);
+ vcpu_clear_flag(vcpu, DEBUG_STATE_SAVE_TRBE);
}
diff --git a/arch/arm64/kvm/hyp/include/hyp/debug-sr.h b/arch/arm64/kvm/hyp/include/hyp/debug-sr.h
index 4ebe9f558f3a..961bbef104a6 100644
--- a/arch/arm64/kvm/hyp/include/hyp/debug-sr.h
+++ b/arch/arm64/kvm/hyp/include/hyp/debug-sr.h
@@ -132,7 +132,7 @@ static inline void __debug_switch_to_guest_common(struct kvm_vcpu *vcpu)
struct kvm_guest_debug_arch *host_dbg;
struct kvm_guest_debug_arch *guest_dbg;

- if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY))
+ if (!vcpu_get_flag(vcpu, DEBUG_DIRTY))
return;

host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
@@ -151,7 +151,7 @@ static inline void __debug_switch_to_host_common(struct kvm_vcpu *vcpu)
struct kvm_guest_debug_arch *host_dbg;
struct kvm_guest_debug_arch *guest_dbg;

- if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY))
+ if (!vcpu_get_flag(vcpu, DEBUG_DIRTY))
return;

host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
@@ -162,7 +162,7 @@ static inline void __debug_switch_to_host_common(struct kvm_vcpu *vcpu)
__debug_save_state(guest_dbg, guest_ctxt);
__debug_restore_state(host_dbg, host_ctxt);

- vcpu->arch.flags &= ~KVM_ARM64_DEBUG_DIRTY;
+ vcpu_clear_flag(vcpu, DEBUG_DIRTY);
}

#endif /* __ARM64_KVM_HYP_DEBUG_SR_H__ */
diff --git a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h
index 7ecca8b07851..baa5b9b3dde5 100644
--- a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h
+++ b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h
@@ -195,7 +195,7 @@ static inline void __sysreg32_save_state(struct kvm_vcpu *vcpu)
__vcpu_sys_reg(vcpu, DACR32_EL2) = read_sysreg(dacr32_el2);
__vcpu_sys_reg(vcpu, IFSR32_EL2) = read_sysreg(ifsr32_el2);

- if (has_vhe() || vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY)
+ if (has_vhe() || vcpu_get_flag(vcpu, DEBUG_DIRTY))
__vcpu_sys_reg(vcpu, DBGVCR32_EL2) = read_sysreg(dbgvcr32_el2);
}

@@ -212,7 +212,7 @@ static inline void __sysreg32_restore_state(struct kvm_vcpu *vcpu)
write_sysreg(__vcpu_sys_reg(vcpu, DACR32_EL2), dacr32_el2);
write_sysreg(__vcpu_sys_reg(vcpu, IFSR32_EL2), ifsr32_el2);

- if (has_vhe() || vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY)
+ if (has_vhe() || vcpu_get_flag(vcpu, DEBUG_DIRTY))
write_sysreg(__vcpu_sys_reg(vcpu, DBGVCR32_EL2), dbgvcr32_el2);
}

diff --git a/arch/arm64/kvm/hyp/nvhe/debug-sr.c b/arch/arm64/kvm/hyp/nvhe/debug-sr.c
index df361d839902..e17455773b98 100644
--- a/arch/arm64/kvm/hyp/nvhe/debug-sr.c
+++ b/arch/arm64/kvm/hyp/nvhe/debug-sr.c
@@ -84,10 +84,10 @@ static void __debug_restore_trace(u64 trfcr_el1)
void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu)
{
/* Disable and flush SPE data generation */
- if (vcpu->arch.flags & KVM_ARM64_DEBUG_STATE_SAVE_SPE)
+ if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE))
__debug_save_spe(&vcpu->arch.host_debug_state.pmscr_el1);
/* Disable and flush Self-Hosted Trace generation */
- if (vcpu->arch.flags & KVM_ARM64_DEBUG_STATE_SAVE_TRBE)
+ if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE))
__debug_save_trace(&vcpu->arch.host_debug_state.trfcr_el1);
}

@@ -98,9 +98,9 @@ void __debug_switch_to_guest(struct kvm_vcpu *vcpu)

void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu)
{
- if (vcpu->arch.flags & KVM_ARM64_DEBUG_STATE_SAVE_SPE)
+ if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE))
__debug_restore_spe(vcpu->arch.host_debug_state.pmscr_el1);
- if (vcpu->arch.flags & KVM_ARM64_DEBUG_STATE_SAVE_TRBE)
+ if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE))
__debug_restore_trace(vcpu->arch.host_debug_state.trfcr_el1);
}

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index c06c0477fab5..f24797c57df8 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -387,7 +387,7 @@ static bool trap_debug_regs(struct kvm_vcpu *vcpu,
{
if (p->is_write) {
vcpu_write_sys_reg(vcpu, p->regval, r->reg);
- vcpu->arch.flags |= KVM_ARM64_DEBUG_DIRTY;
+ vcpu_set_flag(vcpu, DEBUG_DIRTY);
} else {
p->regval = vcpu_read_sys_reg(vcpu, r->reg);
}
@@ -403,8 +403,8 @@ static bool trap_debug_regs(struct kvm_vcpu *vcpu,
* A 32 bit write to a debug register leave top bits alone
* A 32 bit read from a debug register only returns the bottom bits
*
- * All writes will set the KVM_ARM64_DEBUG_DIRTY flag to ensure the
- * hyp.S code switches between host and guest values in future.
+ * All writes will set the DEBUG_DIRTY flag to ensure the hyp code
+ * switches between host and guest values in future.
*/
static void reg_to_dbg(struct kvm_vcpu *vcpu,
struct sys_reg_params *p,
@@ -420,7 +420,7 @@ static void reg_to_dbg(struct kvm_vcpu *vcpu,
val |= (p->regval & (mask >> shift)) << shift;
*dbg_reg = val;

- vcpu->arch.flags |= KVM_ARM64_DEBUG_DIRTY;
+ vcpu_set_flag(vcpu, DEBUG_DIRTY);
}

static void dbg_to_reg(struct kvm_vcpu *vcpu,
--
2.34.1