From: Dave Martin Dave.Martin@arm.com
[ Upstream commit be25bbb392fad3a721d6d21b78639b60612b5439 ]
In preparation for adding logic to filter out some KVM_REG_ARM_CORE registers from the KVM_GET_REG_LIST output, this patch factors out the core register enumeration into a separate function and rebuilds num_core_regs() on top of it.
This may be a little more expensive (depending on how good a job the compiler does of specialising the code), but KVM_GET_REG_LIST is not a hot path.
This will make it easier to consolidate ID filtering code in one place.
No functional change.
Signed-off-by: Dave Martin Dave.Martin@arm.com Reviewed-by: Julien Thierry julien.thierry@arm.com Tested-by: zhang.lei zhang.lei@jp.fujitsu.com Signed-off-by: Marc Zyngier marc.zyngier@arm.com Signed-off-by: Takahiro Itazuri itazur@amazon.com --- arch/arm64/kvm/guest.c | 32 ++++++++++++++++++++++++-------- 1 file changed, 24 insertions(+), 8 deletions(-)
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 76d27edf33cb..d29cb34a828f 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -193,9 +193,28 @@ int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) return -EINVAL; }
+static int kvm_arm_copy_core_reg_indices(u64 __user *uindices) +{ + unsigned int i; + int n = 0; + const u64 core_reg = KVM_REG_ARM64 | KVM_REG_SIZE_U64 | KVM_REG_ARM_CORE; + + for (i = 0; i < sizeof(struct kvm_regs) / sizeof(__u32); i++) { + if (uindices) { + if (put_user(core_reg | i, uindices)) + return -EFAULT; + uindices++; + } + + n++; + } + + return n; +} + static unsigned long num_core_regs(void) { - return sizeof(struct kvm_regs) / sizeof(__u32); + return kvm_arm_copy_core_reg_indices(NULL); }
/** @@ -269,15 +288,12 @@ unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu) */ int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices) { - unsigned int i; - const u64 core_reg = KVM_REG_ARM64 | KVM_REG_SIZE_U64 | KVM_REG_ARM_CORE; int ret;
- for (i = 0; i < sizeof(struct kvm_regs) / sizeof(__u32); i++) { - if (put_user(core_reg | i, uindices)) - return -EFAULT; - uindices++; - } + ret = kvm_arm_copy_core_reg_indices(uindices); + if (ret) + return ret; + uindices += ret;
ret = kvm_arm_copy_fw_reg_indices(vcpu, uindices); if (ret)