KVM: PPC: Implement correct SID mapping on Book3s_32
Up until now we were doing segment mappings wrong on Book3s_32. For Book3s_64
we were using a trick where we know that a single mmu_context gives us 16 bits
of context ids.
The mm system on Book3s_32 instead uses a clever algorithm to distribute VSIDs
across the available range, so a context id really only gives us 16 available
VSIDs.
To keep at least a few guest processes in the SID shadow, let's map a number of
contexts that we can use as VSID pool. This makes the code be actually correct
and shouldn't hurt performance too much.
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
index be8aac2..d62e703 100644
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -60,6 +60,13 @@
#define SID_MAP_NUM (1 << SID_MAP_BITS)
#define SID_MAP_MASK (SID_MAP_NUM - 1)
+#ifdef CONFIG_PPC_BOOK3S_64
+#define SID_CONTEXTS 1
+#else
+#define SID_CONTEXTS 128
+#define VSID_POOL_SIZE (SID_CONTEXTS * 16)
+#endif
+
struct kvmppc_vcpu_book3s {
struct kvm_vcpu vcpu;
struct kvmppc_book3s_shadow_vcpu *shadow_vcpu;
@@ -78,10 +85,14 @@
u64 sdr1;
u64 hior;
u64 msr_mask;
- u64 vsid_first;
u64 vsid_next;
+#ifdef CONFIG_PPC_BOOK3S_32
+ u32 vsid_pool[VSID_POOL_SIZE];
+#else
+ u64 vsid_first;
u64 vsid_max;
- int context_id;
+#endif
+ int context_id[SID_CONTEXTS];
ulong prog_flags; /* flags to inject when giving a 700 trap */
};