KVM: arm64: Factor out core register ID enumeration

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>
This commit is contained in:
Dave Martin 2019-03-15 15:47:04 +00:00 committed by Marc Zyngier
parent dc52f31a92
commit be25bbb392
1 changed files with 25 additions and 8 deletions

View File

@ -23,6 +23,7 @@
#include <linux/err.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
@ -194,9 +195,28 @@ 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);
}
/**
@ -276,15 +296,12 @@ 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)