From: Dave Martin <Dave.Martin@arm.com>
Date: Fri, 15 Mar 2019 15:47:04 +0000
Subject: KVM: arm64: Factor out core register ID enumeration
Git-commit: be25bbb392fad3a721d6d21b78639b60612b5439
Patch-mainline: v5.2-rc1
References: bsc#1174726
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: Matthias Brugger <mbrugger@suse.com>
---
arch/arm64/kvm/guest.c | 33 +++++++++++++++++++++++++--------
1 file changed, 25 insertions(+), 8 deletions(-)
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -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
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 kv
*/
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)