KVM: PPC: Book3S: Get/set guest SPRs using the GET/SET_ONE_REG interface

This enables userspace to get and set various SPRs (special-purpose
registers) using the KVM_[GS]ET_ONE_REG ioctls.  With this, userspace
can get and set all the SPRs that are part of the guest state, either
through the KVM_[GS]ET_REGS ioctls, the KVM_[GS]ET_SREGS ioctls, or
the KVM_[GS]ET_ONE_REG ioctls.

The SPRs that are added here are:

- DABR:  Data address breakpoint register
- DSCR:  Data stream control register
- PURR:  Processor utilization of resources register
- SPURR: Scaled PURR
- DAR:   Data address register
- DSISR: Data storage interrupt status register
- AMR:   Authority mask register
- UAMOR: User authority mask override register
- MMCR0, MMCR1, MMCRA: Performance monitor unit control registers
- PMC1..PMC8: Performance monitor unit counter registers

In order to reduce code duplication between PR and HV KVM code, this
moves the kvm_vcpu_ioctl_[gs]et_one_reg functions into book3s.c and
centralizes the copying between user and kernel space there.  The
registers that are handled differently between PR and HV, and those
that exist only in one flavor, are handled in kvmppc_[gs]et_one_reg()
functions that are specific to each flavor.

Signed-off-by: Paul Mackerras <paulus@samba.org>
[agraf: minimal style fixes]
Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 32 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index 3fb980d293e5..709f0ddae1f1 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -28,6 +28,7 @@
 #include <linux/types.h>
 #include <linux/kvm_types.h>
 #include <linux/kvm_host.h>
+#include <linux/bug.h>
 #ifdef CONFIG_PPC_BOOK3S
 #include <asm/kvm_book3s.h>
 #else
@@ -196,6 +197,35 @@ static inline u32 kvmppc_set_field(u64 inst, int msb, int lsb, int value)
 	return r;
 }
 
+union kvmppc_one_reg {
+	u32	wval;
+	u64	dval;
+};
+
+#define one_reg_size(id)	\
+	(1ul << (((id) & KVM_REG_SIZE_MASK) >> KVM_REG_SIZE_SHIFT))
+
+#define get_reg_val(id, reg)	({		\
+	union kvmppc_one_reg __u;		\
+	switch (one_reg_size(id)) {		\
+	case 4: __u.wval = (reg); break;	\
+	case 8: __u.dval = (reg); break;	\
+	default: BUG();				\
+	}					\
+	__u;					\
+})
+
+
+#define set_reg_val(id, val)	({		\
+	u64 __v;				\
+	switch (one_reg_size(id)) {		\
+	case 4: __v = (val).wval; break;	\
+	case 8: __v = (val).dval; break;	\
+	default: BUG();				\
+	}					\
+	__v;					\
+})
+
 void kvmppc_core_get_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs);
 int kvmppc_core_set_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs);
 
@@ -204,6 +234,8 @@ int kvmppc_set_sregs_ivor(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs);
 
 int kvm_vcpu_ioctl_get_one_reg(struct kvm_vcpu *vcpu, struct kvm_one_reg *reg);
 int kvm_vcpu_ioctl_set_one_reg(struct kvm_vcpu *vcpu, struct kvm_one_reg *reg);
+int kvmppc_get_one_reg(struct kvm_vcpu *vcpu, u64 id, union kvmppc_one_reg *);
+int kvmppc_set_one_reg(struct kvm_vcpu *vcpu, u64 id, union kvmppc_one_reg *);
 
 void kvmppc_set_pid(struct kvm_vcpu *vcpu, u32 pid);