[PATCH v2 33/33] KVM: PPC: Book3S HV: Use hypercalls for TLB invalidation when nested

[Paul Mackerras]

This adds code to call the H_TLB_INVALIDATE hypercall when running as
a guest, in the cases where we need to invalidate TLBs (or other MMU
caches) as part of managing the mappings for a nested guest.  Calling
H_TLB_INVALIDATE is an alternative to doing the tlbie instruction and
having it be emulated by our hypervisor.

Signed-off-by: Paul Mackerras <paulus at ozlabs.org>
---
 arch/powerpc/include/asm/kvm_book3s_64.h |  5 +++++
 arch/powerpc/kvm/book3s_64_mmu_radix.c   | 30 ++++++++++++++++++++++++++++--
 arch/powerpc/kvm/book3s_hv_nested.c      | 19 ++++++++++++-------
 3 files changed, 45 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h
index 6066913..703924f 100644
--- a/arch/powerpc/include/asm/kvm_book3s_64.h
+++ b/arch/powerpc/include/asm/kvm_book3s_64.h
@@ -24,6 +24,7 @@
 #include <asm/bitops.h>
 #include <asm/book3s/64/mmu-hash.h>
 #include <asm/cpu_has_feature.h>
+#include <asm/ppc-opcode.h>
 
 #ifdef CONFIG_PPC_PSERIES
 static inline bool kvmhv_on_pseries(void)
@@ -121,6 +122,10 @@ struct kvm_nested_guest *kvmhv_get_nested(struct kvm *kvm, int l1_lpid,
 void kvmhv_put_nested(struct kvm_nested_guest *gp);
 int kvmhv_nested_next_lpid(struct kvm *kvm, int lpid);
 
+/* Encoding of first parameter for H_TLB_INVALIDATE */
+#define H_TLBIE_P1_ENC(ric, prs, r)	(___PPC_RIC(ric) | ___PPC_PRS(prs) | \
+					 ___PPC_R(r))
+
 /* Power architecture requires HPT is at least 256kiB, at most 64TiB */
 #define PPC_MIN_HPT_ORDER	18
 #define PPC_MAX_HPT_ORDER	46
diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c
index b74abdd..6c93f5c 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_radix.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c
@@ -201,17 +201,43 @@ static void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr,
 				    unsigned int pshift, unsigned int lpid)
 {
 	unsigned long psize = PAGE_SIZE;
+	int psi;
+	long rc;
+	unsigned long rb;
 
 	if (pshift)
 		psize = 1UL << pshift;
+	else
+		pshift = PAGE_SHIFT;
 
 	addr &= ~(psize - 1);
-	radix__flush_tlb_lpid_page(lpid, addr, psize);
+
+	if (!kvmhv_on_pseries()) {
+		radix__flush_tlb_lpid_page(lpid, addr, psize);
+		return;
+	}
+
+	psi = shift_to_mmu_psize(pshift);
+	rb = addr | (mmu_get_ap(psi) << PPC_BITLSHIFT(58));
+	rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(0, 0, 1),
+				lpid, rb);
+	if (rc)
+		pr_err("KVM: TLB page invalidation hcall failed, rc=%ld\n", rc);
 }
 
 static void kvmppc_radix_flush_pwc(struct kvm *kvm, unsigned int lpid)
 {
-	radix__flush_pwc_lpid(lpid);
+	long rc;
+
+	if (!kvmhv_on_pseries()) {
+		radix__flush_pwc_lpid(lpid);
+		return;
+	}
+
+	rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(1, 0, 1),
+				lpid, TLBIEL_INVAL_SET_LPID);
+	if (rc)
+		pr_err("KVM: TLB PWC invalidation hcall failed, rc=%ld\n", rc);
 }
 
 static unsigned long kvmppc_radix_update_pte(struct kvm *kvm, pte_t *ptep,
diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c
index 5879c8d..e35ee4f 100644
--- a/arch/powerpc/kvm/book3s_hv_nested.c
+++ b/arch/powerpc/kvm/book3s_hv_nested.c
@@ -366,15 +366,20 @@ void kvmhv_nested_exit(void)
 
 void kvmhv_set_ptbl_entry(unsigned int lpid, u64 dw0, u64 dw1)
 {
-	if (cpu_has_feature(CPU_FTR_HVMODE)) {
+	long rc;
+
+	if (!kvmhv_on_pseries()) {
 		mmu_partition_table_set_entry(lpid, dw0, dw1);
-	} else {
-		pseries_partition_tb[lpid].patb0 = cpu_to_be64(dw0);
-		pseries_partition_tb[lpid].patb1 = cpu_to_be64(dw1);
-		/* this will be emulated, L0 will do the necessary barriers */
-		asm volatile(PPC_TLBIE_5(%0, %1, 2, 0, 1) : :
-			     "r" (TLBIEL_INVAL_SET_LPID), "r" (lpid));
+		return;
 	}
+
+	pseries_partition_tb[lpid].patb0 = cpu_to_be64(dw0);
+	pseries_partition_tb[lpid].patb1 = cpu_to_be64(dw1);
+	/* L0 will do the necessary barriers */
+	rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(2, 0, 1),
+				lpid, TLBIEL_INVAL_SET_LPID);
+	if (rc)
+		pr_err("KVM: TLB LPID invalidation hcall failed, rc=%ld\n", rc);
 }
 
 static void kvmhv_set_nested_ptbl(struct kvm_nested_guest *gp)
-- 
2.7.4