Subject: [PATCH 2/2] powerpc/64s/radix: keep kernel ERAT over local process/guest invalidates

From: Nicholas Piggin <[email-masked]>
Date: Sun, 23 Jun 2019 20:41:52 +1000

ISAv3 radix modes provide SLBIA variants which can invalidate ERAT for
effPID!=0 or for effLPID!=0, which allows user and guest invalidations
to retain kernel/host ERAT entries.

Signed-off-by: Nicholas Piggin <[email-masked]>
---
 arch/powerpc/include/asm/ppc-opcode.h | 8 ++++++++
 arch/powerpc/kvm/book3s_hv_builtin.c  | 6 ++++--
 arch/powerpc/mm/book3s64/radix_tlb.c  | 6 +++---
 3 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/include/asm/ppc-opcode.h b/arch/powerpc/include/asm/ppc-opcode.h
index 156102828a3b..0f67d672f719 100644
--- a/arch/powerpc/include/asm/ppc-opcode.h
+++ b/arch/powerpc/include/asm/ppc-opcode.h
@@ -588,7 +588,15 @@
 
 #define PPC_SLBIA(IH)	stringify_in_c(.long PPC_INST_SLBIA | \
 				       ((IH & 0x7) << 21))
+
+/*
+ * These may only be used by ARCH_300 (radix implies ARCH_300).
+ * USER/GUEST invalidates may only be used by radix mode (on HPT these
+ * would also invalidate various SLBEs which may not be desired).
+ */
 #define PPC_ARCH_300_INVALIDATE_ERAT	PPC_SLBIA(7)
+#define PPC_RADIX_INVALIDATE_ERAT_USER	PPC_SLBIA(3)
+#define PPC_RADIX_INVALIDATE_ERAT_GUEST	PPC_SLBIA(6)
 
 #define VCMPEQUD_RC(vrt, vra, vrb)	stringify_in_c(.long PPC_INST_VCMPEQUD | \
 			      ___PPC_RT(vrt) | ___PPC_RA(vra) | \
diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
index 960154262665..08a32c3e6153 100644
--- a/arch/powerpc/kvm/book3s_hv_builtin.c
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -820,6 +820,8 @@ static void flush_guest_tlb(struct kvm *kvm)
 				     : : "r" (rb), "i" (1), "i" (1), "i" (0),
 				       "r" (0) : "memory");
 		}
+		asm volatile("ptesync": : :"memory");
+		asm volatile(PPC_RADIX_INVALIDATE_ERAT_GUEST : : :"memory");
 	} else {
 		for (set = 0; set < kvm->arch.tlb_sets; ++set) {
 			/* R=0 PRS=0 RIC=0 */
@@ -828,9 +830,9 @@ static void flush_guest_tlb(struct kvm *kvm)
 				       "r" (0) : "memory");
 			rb += PPC_BIT(51);	/* increment set number */
 		}
+		asm volatile("ptesync": : :"memory");
+		asm volatile(PPC_ARCH_300_INVALIDATE_ERAT : : :"memory");
 	}
-	asm volatile("ptesync": : :"memory");
-	asm volatile(PPC_ARCH_300_INVALIDATE_ERAT : : :"memory");
 }
 
 void kvmppc_check_need_tlb_flush(struct kvm *kvm, int pcpu,
diff --git a/arch/powerpc/mm/book3s64/radix_tlb.c b/arch/powerpc/mm/book3s64/radix_tlb.c
index 17f33b6645f9..fb880a043898 100644
--- a/arch/powerpc/mm/book3s64/radix_tlb.c
+++ b/arch/powerpc/mm/book3s64/radix_tlb.c
@@ -258,7 +258,7 @@ static inline void _tlbiel_pid(unsigned long pid, unsigned long ric)
 		__tlbiel_pid(pid, set, RIC_FLUSH_TLB);
 
 	asm volatile("ptesync": : :"memory");
-	asm volatile(PPC_ARCH_300_INVALIDATE_ERAT "; isync" : : :"memory");
+	asm volatile(PPC_RADIX_INVALIDATE_ERAT_USER "; isync" : : :"memory");
 }
 
 static inline void _tlbie_pid(unsigned long pid, unsigned long ric)
@@ -310,7 +310,7 @@ static inline void _tlbiel_lpid(unsigned long lpid, unsigned long ric)
 		__tlbiel_lpid(lpid, set, RIC_FLUSH_TLB);
 
 	asm volatile("ptesync": : :"memory");
-	asm volatile(PPC_ARCH_300_INVALIDATE_ERAT "; isync" : : :"memory");
+	asm volatile(PPC_RADIX_INVALIDATE_ERAT_GUEST "; isync" : : :"memory");
 }
 
 static inline void _tlbie_lpid(unsigned long lpid, unsigned long ric)
@@ -362,7 +362,7 @@ static inline void _tlbiel_lpid_guest(unsigned long lpid, unsigned long ric)
 		__tlbiel_lpid_guest(lpid, set, RIC_FLUSH_TLB);
 
 	asm volatile("ptesync": : :"memory");
-	asm volatile(PPC_ARCH_300_INVALIDATE_ERAT : : :"memory");
+	asm volatile(PPC_RADIX_INVALIDATE_ERAT_GUEST : : :"memory");
 }

-- 
2.20.1