The GICv3 userspace accessors are all about dealing with conversion
between fields from architectural registers and internal representations.
However, and owing to the age of this code, the accessors use
a combination of shift/mask that is hard to read. It is nonetheless
easy to make it better by using the FIELD_{GET,PREP} macros that solely
rely on a mask.
This results in somewhat nicer looking code, and is probably easier
to maintain.
Reviewed-by: Reiji Watanabe <reijiw@xxxxxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
arch/arm64/kvm/vgic-sys-reg-v3.c | 60 ++++++++++++++------------------
1 file changed, 27 insertions(+), 33 deletions(-)
diff --git a/arch/arm64/kvm/vgic-sys-reg-v3.c b/arch/arm64/kvm/vgic-sys-reg-v3.c
index b755b02bc8ba..9e7c486b48c2 100644
--- a/arch/arm64/kvm/vgic-sys-reg-v3.c
+++ b/arch/arm64/kvm/vgic-sys-reg-v3.c
@@ -23,30 +23,25 @@ static int set_gic_ctlr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
* Disallow restoring VM state if not supported by this
* hardware.
*/
- host_pri_bits = ((val & ICC_CTLR_EL1_PRI_BITS_MASK) >>
- ICC_CTLR_EL1_PRI_BITS_SHIFT) + 1;
+ host_pri_bits = FIELD_GET(ICC_CTLR_EL1_PRI_BITS_MASK, val) + 1;
if (host_pri_bits > vgic_v3_cpu->num_pri_bits)
return -EINVAL;
vgic_v3_cpu->num_pri_bits = host_pri_bits;
- host_id_bits = (val & ICC_CTLR_EL1_ID_BITS_MASK) >>
- ICC_CTLR_EL1_ID_BITS_SHIFT;
+ host_id_bits = FIELD_GET(ICC_CTLR_EL1_ID_BITS_MASK, val);
if (host_id_bits > vgic_v3_cpu->num_id_bits)
return -EINVAL;
vgic_v3_cpu->num_id_bits = host_id_bits;
- host_seis = ((kvm_vgic_global_state.ich_vtr_el2 &
- ICH_VTR_SEIS_MASK) >> ICH_VTR_SEIS_SHIFT);
- seis = (val & ICC_CTLR_EL1_SEIS_MASK) >>
- ICC_CTLR_EL1_SEIS_SHIFT;
+ host_seis = FIELD_GET(ICH_VTR_SEIS_MASK, kvm_vgic_global_state.ich_vtr_el2);
+ seis = FIELD_GET(ICC_CTLR_EL1_SEIS_MASK, val);
if (host_seis != seis)
return -EINVAL;
- host_a3v = ((kvm_vgic_global_state.ich_vtr_el2 &
- ICH_VTR_A3V_MASK) >> ICH_VTR_A3V_SHIFT);
- a3v = (val & ICC_CTLR_EL1_A3V_MASK) >> ICC_CTLR_EL1_A3V_SHIFT;
+ host_a3v = FIELD_GET(ICH_VTR_A3V_MASK, kvm_vgic_global_state.ich_vtr_el2);
+ a3v = FIELD_GET(ICC_CTLR_EL1_A3V_MASK, val);
if (host_a3v != a3v)
return -EINVAL;
@@ -54,8 +49,8 @@ static int set_gic_ctlr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
* Here set VMCR.CTLR in ICC_CTLR_EL1 layout.
* The vgic_set_vmcr() will convert to ICH_VMCR layout.
*/
- vmcr.cbpr = (val & ICC_CTLR_EL1_CBPR_MASK) >> ICC_CTLR_EL1_CBPR_SHIFT;
- vmcr.eoim = (val & ICC_CTLR_EL1_EOImode_MASK) >> ICC_CTLR_EL1_EOImode_SHIFT;
+ vmcr.cbpr = FIELD_GET(ICC_CTLR_EL1_CBPR_MASK, val);
+ vmcr.eoim = FIELD_GET(ICC_CTLR_EL1_EOImode_MASK, val);
vgic_set_vmcr(vcpu, &vmcr);
return 0;
@@ -70,20 +65,19 @@ static int get_gic_ctlr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
vgic_get_vmcr(vcpu, &vmcr);
val = 0;
- val |= (vgic_v3_cpu->num_pri_bits - 1) << ICC_CTLR_EL1_PRI_BITS_SHIFT;
- val |= vgic_v3_cpu->num_id_bits << ICC_CTLR_EL1_ID_BITS_SHIFT;
- val |= ((kvm_vgic_global_state.ich_vtr_el2 &
- ICH_VTR_SEIS_MASK) >> ICH_VTR_SEIS_SHIFT) <<
- ICC_CTLR_EL1_SEIS_SHIFT;
- val |= ((kvm_vgic_global_state.ich_vtr_el2 &
- ICH_VTR_A3V_MASK) >> ICH_VTR_A3V_SHIFT) <<
- ICC_CTLR_EL1_A3V_SHIFT;
+ val |= FIELD_PREP(ICC_CTLR_EL1_PRI_BITS_MASK, vgic_v3_cpu->num_pri_bits - 1);
+ val |= FIELD_PREP(ICC_CTLR_EL1_ID_BITS_MASK, vgic_v3_cpu->num_id_bits);
+ val |= FIELD_PREP(ICC_CTLR_EL1_SEIS_MASK,
+ FIELD_GET(ICH_VTR_SEIS_MASK,
+ kvm_vgic_global_state.ich_vtr_el2));
+ val |= FIELD_PREP(ICC_CTLR_EL1_A3V_MASK,
+ FIELD_GET(ICH_VTR_A3V_MASK, kvm_vgic_global_state.ich_vtr_el2));
/*
* The VMCR.CTLR value is in ICC_CTLR_EL1 layout.
* Extract it directly using ICC_CTLR_EL1 reg definitions.
*/
- val |= (vmcr.cbpr << ICC_CTLR_EL1_CBPR_SHIFT) & ICC_CTLR_EL1_CBPR_MASK;
- val |= (vmcr.eoim << ICC_CTLR_EL1_EOImode_SHIFT) & ICC_CTLR_EL1_EOImode_MASK;
+ val |= FIELD_PREP(ICC_CTLR_EL1_CBPR_MASK, vmcr.cbpr);
+ val |= FIELD_PREP(ICC_CTLR_EL1_EOImode_MASK, vmcr.eoim);
*valp = val;
@@ -96,7 +90,7 @@ static int set_gic_pmr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
struct vgic_vmcr vmcr;
vgic_get_vmcr(vcpu, &vmcr);
- vmcr.pmr = (val & ICC_PMR_EL1_MASK) >> ICC_PMR_EL1_SHIFT;
+ vmcr.pmr = FIELD_GET(ICC_PMR_EL1_MASK, val);
vgic_set_vmcr(vcpu, &vmcr);
return 0;
@@ -108,7 +102,7 @@ static int get_gic_pmr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
struct vgic_vmcr vmcr;
vgic_get_vmcr(vcpu, &vmcr);
- *val = (vmcr.pmr << ICC_PMR_EL1_SHIFT) & ICC_PMR_EL1_MASK;
+ *val = FIELD_PREP(ICC_PMR_EL1_MASK, vmcr.pmr);
return 0;
}
@@ -119,7 +113,7 @@ static int set_gic_bpr0(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
struct vgic_vmcr vmcr;
vgic_get_vmcr(vcpu, &vmcr);
- vmcr.bpr = (val & ICC_BPR0_EL1_MASK) >> ICC_BPR0_EL1_SHIFT;
+ vmcr.bpr = FIELD_GET(ICC_BPR0_EL1_MASK, val);
vgic_set_vmcr(vcpu, &vmcr);
return 0;
@@ -131,7 +125,7 @@ static int get_gic_bpr0(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
struct vgic_vmcr vmcr;
vgic_get_vmcr(vcpu, &vmcr);
- *val = (vmcr.bpr << ICC_BPR0_EL1_SHIFT) & ICC_BPR0_EL1_MASK;
+ *val = FIELD_PREP(ICC_BPR0_EL1_MASK, vmcr.bpr);
return 0;
}
@@ -143,7 +137,7 @@ static int set_gic_bpr1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
vgic_get_vmcr(vcpu, &vmcr);
if (!vmcr.cbpr) {
- vmcr.abpr = (val & ICC_BPR1_EL1_MASK) >> ICC_BPR1_EL1_SHIFT;
+ vmcr.abpr = FIELD_GET(ICC_BPR1_EL1_MASK, val);
vgic_set_vmcr(vcpu, &vmcr);
}
@@ -157,7 +151,7 @@ static int get_gic_bpr1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
vgic_get_vmcr(vcpu, &vmcr);
if (!vmcr.cbpr)
- *val = (vmcr.abpr << ICC_BPR1_EL1_SHIFT) & ICC_BPR1_EL1_MASK;
+ *val = FIELD_PREP(ICC_BPR1_EL1_MASK, vmcr.abpr);
else
*val = min((vmcr.bpr + 1), 7U);
@@ -171,7 +165,7 @@ static int set_gic_grpen0(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
struct vgic_vmcr vmcr;
vgic_get_vmcr(vcpu, &vmcr);
- vmcr.grpen0 = (val & ICC_IGRPEN0_EL1_MASK) >> ICC_IGRPEN0_EL1_SHIFT;
+ vmcr.grpen0 = FIELD_GET(ICC_IGRPEN0_EL1_MASK, val);
vgic_set_vmcr(vcpu, &vmcr);
return 0;
@@ -183,7 +177,7 @@ static int get_gic_grpen0(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
struct vgic_vmcr vmcr;
vgic_get_vmcr(vcpu, &vmcr);
- *val = (vmcr.grpen0 << ICC_IGRPEN0_EL1_SHIFT) & ICC_IGRPEN0_EL1_MASK;
+ *val = FIELD_PREP(ICC_IGRPEN0_EL1_MASK, vmcr.grpen0);
return 0;
}
@@ -194,7 +188,7 @@ static int set_gic_grpen1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
struct vgic_vmcr vmcr;
vgic_get_vmcr(vcpu, &vmcr);
- vmcr.grpen1 = (val & ICC_IGRPEN1_EL1_MASK) >> ICC_IGRPEN1_EL1_SHIFT;
+ vmcr.grpen1 = FIELD_GET(ICC_IGRPEN1_EL1_MASK, val);
vgic_set_vmcr(vcpu, &vmcr);
return 0;
@@ -206,7 +200,7 @@ static int get_gic_grpen1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
struct vgic_vmcr vmcr;
vgic_get_vmcr(vcpu, &vmcr);
- *val = (vmcr.grpen1 << ICC_IGRPEN1_EL1_SHIFT) & ICC_IGRPEN1_EL1_MASK;
+ *val = FIELD_GET(ICC_IGRPEN1_EL1_MASK, vmcr.grpen1);
return 0;
}
--
2.34.1
_______________________________________________
kvmarm mailing list
kvmarm@xxxxxxxxxxxxxxxxxxxxx
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
