[Qemu-devel] [PATCH 2/2] PPC: KVM: Update HIOR code to new interface

[Alexander Graf <agraf@suse.de>]

Unfortunately the HIOR setting code slipped into upstream QEMU
before it was pulled into upstream KVM. And since Murphy is always
right, comments on the patches only emerged on the pull request
leading to changes in the interface.

So here's an update to the HIOR setting. While at it, I also relaxed
it a bit since for HV KVM we can already run fine without and 3.2
works just fine with HV KVM but when not setting HIOR. We will only
need this when running PAPR in PR KVM.

Since we accidently changed the ABI and API along the way, we have
to update the underlying kernel headers together with the code that
uses it to not break bisectability.

Signed-off-by: Alexander Graf <agraf@suse.de>
---
 linux-headers/asm-powerpc/kvm.h |    2 +-
 linux-headers/linux/kvm.h       |   37 ++++++++++++++++++++-----------------
 target-ppc/kvm.c                |   10 +++++++---
 3 files changed, 28 insertions(+), 21 deletions(-)

diff --git a/linux-headers/asm-powerpc/kvm.h b/linux-headers/asm-powerpc/kvm.h
index 1f0cb55..b921c3f 100644
--- a/linux-headers/asm-powerpc/kvm.h
+++ b/linux-headers/asm-powerpc/kvm.h
@@ -324,6 +324,6 @@ struct kvm_book3e_206_tlb_params {
 	__u32 reserved[8];
 };
 
-#define KVM_ONE_REG_PPC_HIOR	KVM_ONE_REG_PPC | 0x100
+#define KVM_REG_PPC_HIOR	(KVM_REG_PPC | KVM_REG_SIZE_U64 | 0x1)
 
 #endif /* __LINUX_KVM_POWERPC_H */
diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
index 4847813..f6b5343 100644
--- a/linux-headers/linux/kvm.h
+++ b/linux-headers/linux/kvm.h
@@ -684,30 +684,33 @@ struct kvm_dirty_tlb {
 
 /* Available with KVM_CAP_ONE_REG */
 
-#define KVM_ONE_REG_GENERIC		0x0000000000000000ULL
+#define KVM_REG_ARCH_MASK	0xff00000000000000ULL
+#define KVM_REG_GENERIC		0x0000000000000000ULL
 
 /*
  * Architecture specific registers are to be defined in arch headers and
  * ORed with the arch identifier.
  */
-#define KVM_ONE_REG_PPC			0x1000000000000000ULL
-#define KVM_ONE_REG_X86			0x2000000000000000ULL
-#define KVM_ONE_REG_IA64		0x3000000000000000ULL
-#define KVM_ONE_REG_ARM			0x4000000000000000ULL
-#define KVM_ONE_REG_S390		0x5000000000000000ULL
+#define KVM_REG_PPC		0x1000000000000000ULL
+#define KVM_REG_X86		0x2000000000000000ULL
+#define KVM_REG_IA64		0x3000000000000000ULL
+#define KVM_REG_ARM		0x4000000000000000ULL
+#define KVM_REG_S390		0x5000000000000000ULL
+
+#define KVM_REG_SIZE_SHIFT	52
+#define KVM_REG_SIZE_MASK	0x00f0000000000000ULL
+#define KVM_REG_SIZE_U8		0x0000000000000000ULL
+#define KVM_REG_SIZE_U16	0x0010000000000000ULL
+#define KVM_REG_SIZE_U32	0x0020000000000000ULL
+#define KVM_REG_SIZE_U64	0x0030000000000000ULL
+#define KVM_REG_SIZE_U128	0x0040000000000000ULL
+#define KVM_REG_SIZE_U256	0x0050000000000000ULL
+#define KVM_REG_SIZE_U512	0x0060000000000000ULL
+#define KVM_REG_SIZE_U1024	0x0070000000000000ULL
 
 struct kvm_one_reg {
 	__u64 id;
-	union {
-		__u8 reg8;
-		__u16 reg16;
-		__u32 reg32;
-		__u64 reg64;
-		__u8 reg128[16];
-		__u8 reg256[32];
-		__u8 reg512[64];
-		__u8 reg1024[128];
-	} u;
+	__u64 addr;
 };
 
 /*
@@ -850,7 +853,7 @@ struct kvm_s390_ucas_mapping {
 /* Available with KVM_CAP_SW_TLB */
 #define KVM_DIRTY_TLB		  _IOW(KVMIO,  0xaa, struct kvm_dirty_tlb)
 /* Available with KVM_CAP_ONE_REG */
-#define KVM_GET_ONE_REG		  _IOWR(KVMIO, 0xab, struct kvm_one_reg)
+#define KVM_GET_ONE_REG		  _IOW(KVMIO,  0xab, struct kvm_one_reg)
 #define KVM_SET_ONE_REG		  _IOW(KVMIO,  0xac, struct kvm_one_reg)
 
 #define KVM_DEV_ASSIGN_ENABLE_IOMMU	(1 << 0)
diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c
index ce8ac5b..50cfa02 100644
--- a/target-ppc/kvm.c
+++ b/target-ppc/kvm.c
@@ -740,6 +740,7 @@ void kvmppc_set_papr(CPUState *env)
     struct kvm_one_reg reg = {};
     struct kvm_sregs sregs = {};
     int ret;
+    uint64_t hior = env->spr[SPR_HIOR];
 
     cap.cap = KVM_CAP_PPC_PAPR;
     ret = kvm_vcpu_ioctl(env, KVM_ENABLE_CAP, &cap);
@@ -755,11 +756,14 @@ void kvmppc_set_papr(CPUState *env)
      *     Once we have qdev CPUs, move HIOR to a qdev property and
      *     remove this chunk.
      */
-    reg.id = KVM_ONE_REG_PPC_HIOR;
-    reg.u.reg64 = env->spr[SPR_HIOR];
+    reg.id = KVM_REG_PPC_HIOR;
+    reg.addr = (uintptr_t)&hior;
     ret = kvm_vcpu_ioctl(env, KVM_SET_ONE_REG, &reg);
     if (ret) {
-        goto fail;
+        fprintf(stderr, "Couldn't set HIOR. Maybe you're running an old \n"
+                        "kernel with support for HV KVM but no PAPR PR \n"
+                        "KVM in which case things will work. If they don't \n"
+                        "please update your host kernel!\n");
     }
 
     /* Set SDR1 so kernel space finds the HTAB */
-- 
1.6.0.2