Subject: [PATCH v2 1/2] KVM: PPC: Book3S HV: Add support for H_RPT_INVALIDATE

From: Bharata B Rao <[email-masked]>
Date: Wed, 16 Dec 2020 14:24:46 +0530

Implement H_RPT_INVALIDATE hcall and add KVM capability
KVM_CAP_PPC_RPT_INVALIDATE to indicate the support for the same.

This hcall does two types of TLB invalidations:

1. Process-scoped invalidations for guests with LPCR[GTSE]=0.
   This is currently not used in KVM as GTSE is not usually
   disabled in KVM.
2. Partition-scoped invalidations that an L1 hypervisor does on
   behalf of an L2 guest. This replaces the uses of the existing
   hcall H_TLB_INVALIDATE.

Signed-off-by: Bharata B Rao <[email-masked]>
---
 Documentation/virt/kvm/api.rst                |  17 +++
 .../include/asm/book3s/64/tlbflush-radix.h    |  18 +++
 arch/powerpc/include/asm/kvm_book3s.h         |   3 +
 arch/powerpc/kvm/book3s_hv.c                  | 121 ++++++++++++++++++
 arch/powerpc/kvm/book3s_hv_nested.c           |  94 ++++++++++++++
 arch/powerpc/kvm/powerpc.c                    |   3 +
 arch/powerpc/mm/book3s64/radix_tlb.c          |   4 -
 include/uapi/linux/kvm.h                      |   1 +
 8 files changed, 257 insertions(+), 4 deletions(-)

diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index e00a66d72372..5ce237c0d707 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -6014,6 +6014,23 @@ KVM_EXIT_X86_RDMSR and KVM_EXIT_X86_WRMSR exit notifications which user space
 can then handle to implement model specific MSR handling and/or user notifications
 to inform a user that an MSR was not handled.
 
+7.22 KVM_CAP_PPC_RPT_INVALIDATE
+------------------------------
+
+:Capability: KVM_CAP_PPC_RPT_INVALIDATE
+:Architectures: ppc
+:Type: vm
+
+This capability indicates that the kernel is capable of handling
+H_RPT_INVALIDATE hcall.
+
+In order to enable the use of H_RPT_INVALIDATE in the guest,
+user space might have to advertise it for the guest. For example,
+IBM pSeries (sPAPR) guest starts using it if "hcall-rpt-invalidate" is
+present in the "ibm,hypertas-functions" device-tree property.
+
+This capability is always enabled.
+
 8. Other capabilities.
 ======================
 
diff --git a/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h b/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h
index 94439e0cefc9..aace7e9b2397 100644
--- a/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h
+++ b/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h
@@ -4,6 +4,10 @@
 
 #include <asm/hvcall.h>
 
+#define RIC_FLUSH_TLB 0
+#define RIC_FLUSH_PWC 1
+#define RIC_FLUSH_ALL 2
+
 struct vm_area_struct;
 struct mm_struct;
 struct mmu_gather;
@@ -21,6 +25,20 @@ static inline u64 psize_to_rpti_pgsize(unsigned long psize)
 	return H_RPTI_PAGE_ALL;
 }
 
+static inline int rpti_pgsize_to_psize(unsigned long page_size)
+{
+	if (page_size == H_RPTI_PAGE_4K)
+		return MMU_PAGE_4K;
+	if (page_size == H_RPTI_PAGE_64K)
+		return MMU_PAGE_64K;
+	if (page_size == H_RPTI_PAGE_2M)
+		return MMU_PAGE_2M;
+	if (page_size == H_RPTI_PAGE_1G)
+		return MMU_PAGE_1G;
+	else
+		return MMU_PAGE_64K; /* Default */
+}
+
 static inline int mmu_get_ap(int psize)
 {
 	return mmu_psize_defs[psize].ap;
diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
index d32ec9ae73bd..0f1c5fa6e8ce 100644
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -298,6 +298,9 @@ void kvmhv_set_ptbl_entry(unsigned int lpid, u64 dw0, u64 dw1);
 void kvmhv_release_all_nested(struct kvm *kvm);
 long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu);
 long kvmhv_do_nested_tlbie(struct kvm_vcpu *vcpu);
+long kvmhv_h_rpti_nested(struct kvm_vcpu *vcpu, unsigned long lpid,
+			 unsigned long type, unsigned long pg_sizes,
+			 unsigned long start, unsigned long end);
 int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu,
 			  u64 time_limit, unsigned long lpcr);
 void kvmhv_save_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr);
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index e3b1839fc251..adf2d1191581 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -904,6 +904,118 @@ static int kvmppc_get_yield_count(struct kvm_vcpu *vcpu)
 	return yield_count;
 }
 
+static inline void do_tlb_invalidate_all(unsigned long rb, unsigned long rs)
+{
+	asm volatile("ptesync" : : : "memory");
+	asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
+		: : "r"(rb), "i"(1), "i"(1), "i"(RIC_FLUSH_ALL), "r"(rs)
+		: "memory");
+	asm volatile("eieio; tlbsync; ptesync" : : : "memory");
+}
+
+static inline void do_tlb_invalidate_pwc(unsigned long rb, unsigned long rs)
+{
+	asm volatile("ptesync" : : : "memory");
+	asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
+		: : "r"(rb), "i"(1), "i"(1), "i"(RIC_FLUSH_PWC), "r"(rs)
+		: "memory");
+	asm volatile("eieio; tlbsync; ptesync" : : : "memory");
+}
+
+static inline void do_tlb_invalidate_tlb(unsigned long rb, unsigned long rs)
+{
+	asm volatile("ptesync" : : : "memory");
+	asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
+		: : "r"(rb), "i"(1), "i"(1), "i"(RIC_FLUSH_TLB), "r"(rs)
+		: "memory");
+	asm volatile("eieio; tlbsync; ptesync" : : : "memory");
+}
+
+static void do_tlb_invalidate(unsigned long rs, unsigned long target,
+			      unsigned long type, unsigned long page_size,
+			      unsigned long ap, unsigned long start,
+			      unsigned long end)
+{
+	unsigned long rb;
+	unsigned long addr = start;
+
+	if ((type & H_RPTI_TYPE_ALL) == H_RPTI_TYPE_ALL) {
+		rb = PPC_BIT(53); /* IS = 1 */
+		do_tlb_invalidate_all(rb, rs);
+		return;
+	}
+
+	if (type & H_RPTI_TYPE_PWC) {
+		rb = PPC_BIT(53); /* IS = 1 */
+		do_tlb_invalidate_pwc(rb, rs);
+	}
+
+	if (!addr && end == -1) { /* PID */
+		rb = PPC_BIT(53); /* IS = 1 */
+		do_tlb_invalidate_tlb(rb, rs);
+	} else { /* EA */
+		do {
+			rb = addr & ~(PPC_BITMASK(52, 63));
+			rb |= ap << PPC_BITLSHIFT(58);
+			do_tlb_invalidate_tlb(rb, rs);
+			addr += page_size;
+		} while (addr < end);
+	}
+}
+
+static long kvmppc_h_rpt_invalidate(struct kvm_vcpu *vcpu,
+				    unsigned long pid, unsigned long target,
+				    unsigned long type, unsigned long pg_sizes,
+				    unsigned long start, unsigned long end)
+{
+	unsigned long rs, ap, psize;
+
+	if (!kvm_is_radix(vcpu->kvm))
+		return H_FUNCTION;
+
+	if (end < start)
+		return H_P5;
+
+	if (type & H_RPTI_TYPE_NESTED) {
+		if (!nesting_enabled(vcpu->kvm))
+			return H_FUNCTION;
+
+		/* Support only cores as target */
+		if (target != H_RPTI_TARGET_CMMU)
+			return H_P2;
+
+		return kvmhv_h_rpti_nested(vcpu, pid,
+					   (type & ~H_RPTI_TYPE_NESTED),
+					    pg_sizes, start, end);
+	}
+
+	rs = pid << PPC_BITLSHIFT(31);
+	rs |= vcpu->kvm->arch.lpid;
+
+	if (pg_sizes & H_RPTI_PAGE_64K) {
+		psize = rpti_pgsize_to_psize(pg_sizes & H_RPTI_PAGE_64K);
+		ap = mmu_get_ap(psize);
+		do_tlb_invalidate(rs, target, type, (1UL << 16), ap, start,
+				  end);
+	}
+
+	if (pg_sizes & H_RPTI_PAGE_2M) {
+		psize = rpti_pgsize_to_psize(pg_sizes & H_RPTI_PAGE_2M);
+		ap = mmu_get_ap(psize);
+		do_tlb_invalidate(rs, target, type, (1UL << 21), ap, start,
+				  end);
+	}
+
+	if (pg_sizes & H_RPTI_PAGE_1G) {
+		psize = rpti_pgsize_to_psize(pg_sizes & H_RPTI_PAGE_1G);
+		ap = mmu_get_ap(psize);
+		do_tlb_invalidate(rs, target, type, (1UL << 30), ap, start,
+				  end);
+	}
+
+	return H_SUCCESS;
+}
+
 int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 {
 	unsigned long req = kvmppc_get_gpr(vcpu, 3);
@@ -1112,6 +1224,14 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 		 */
 		ret = kvmppc_h_svm_init_abort(vcpu->kvm);
 		break;
+	case H_RPT_INVALIDATE:
+		ret = kvmppc_h_rpt_invalidate(vcpu, kvmppc_get_gpr(vcpu, 4),
+					      kvmppc_get_gpr(vcpu, 5),
+					      kvmppc_get_gpr(vcpu, 6),
+					      kvmppc_get_gpr(vcpu, 7),
+					      kvmppc_get_gpr(vcpu, 8),
+					      kvmppc_get_gpr(vcpu, 9));
+		break;
 
 	default:
 		return RESUME_HOST;
@@ -1158,6 +1278,7 @@ static int kvmppc_hcall_impl_hv(unsigned long cmd)
 	case H_XIRR_X:
 #endif
 	case H_PAGE_INIT:
+	case H_RPT_INVALIDATE:
 		return 1;
 	}
 
diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c
index 33b58549a9aa..a54ba4b1d4a7 100644
--- a/arch/powerpc/kvm/book3s_hv_nested.c
+++ b/arch/powerpc/kvm/book3s_hv_nested.c
@@ -1149,6 +1149,100 @@ long kvmhv_do_nested_tlbie(struct kvm_vcpu *vcpu)
 	return H_SUCCESS;
 }
 
+static long do_tlb_invalidate_nested_tlb(struct kvm_vcpu *vcpu,
+					 unsigned long lpid,
+					 unsigned long page_size,
+					 unsigned long ap,
+					 unsigned long start,
+					 unsigned long end)
+{
+	unsigned long addr = start;
+	int ret;
+
+	do {
+		ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap,
+						   get_epn(addr));
+		if (ret)
+			return ret;
+		addr += page_size;
+	} while (addr < end);
+
+	return ret;
+}
+
+static long do_tlb_invalidate_nested_all(struct kvm_vcpu *vcpu,
+					 unsigned long lpid)
+{
+	struct kvm *kvm = vcpu->kvm;
+	struct kvm_nested_guest *gp;
+
+	gp = kvmhv_get_nested(kvm, lpid, false);
+	if (gp) {
+		kvmhv_emulate_tlbie_lpid(vcpu, gp, RIC_FLUSH_ALL);
+		kvmhv_put_nested(gp);
+	}
+	return H_SUCCESS;
+}
+
+long kvmhv_h_rpti_nested(struct kvm_vcpu *vcpu, unsigned long lpid,
+			 unsigned long type, unsigned long pg_sizes,
+			 unsigned long start, unsigned long end)
+{
+	struct kvm_nested_guest *gp;
+	long ret;
+	unsigned long psize, ap;
+
+	/*
+	 * If L2 lpid isn't valid, we need to return H_PARAMETER.
+	 * Nested KVM issues a L2 lpid flush call when creating
+	 * partition table entries for L2. This happens even before
+	 * the corresponding shadow lpid is created in HV. Until
+	 * this is fixed, ignore such flush requests.
+	 */
+	gp = kvmhv_find_nested(vcpu->kvm, lpid);
+	if (!gp)
+		return H_SUCCESS;
+
+	if ((type & H_RPTI_TYPE_NESTED_ALL) == H_RPTI_TYPE_NESTED_ALL)
+		return do_tlb_invalidate_nested_all(vcpu, lpid);
+
+	if ((type & H_RPTI_TYPE_TLB) == H_RPTI_TYPE_TLB) {
+		if (pg_sizes & H_RPTI_PAGE_64K) {
+			psize = rpti_pgsize_to_psize(pg_sizes & H_RPTI_PAGE_64K);
+			ap = mmu_get_ap(psize);
+
+			ret = do_tlb_invalidate_nested_tlb(vcpu, lpid,
+							   (1UL << 16),
+							   ap, start, end);
+			if (ret)
+				return H_P4;
+		}
+
+		if (pg_sizes & H_RPTI_PAGE_2M) {
+			psize = rpti_pgsize_to_psize(pg_sizes & H_RPTI_PAGE_2M);
+			ap = mmu_get_ap(psize);
+
+			ret = do_tlb_invalidate_nested_tlb(vcpu, lpid,
+							   (1UL << 21),
+							   ap, start, end);
+			if (ret)
+				return H_P4;
+		}
+
+		if (pg_sizes & H_RPTI_PAGE_1G) {
+			psize = rpti_pgsize_to_psize(pg_sizes & H_RPTI_PAGE_1G);
+			ap = mmu_get_ap(psize);
+
+			ret = do_tlb_invalidate_nested_tlb(vcpu, lpid,
+							   (1UL << 30),
+							   ap, start, end);
+			if (ret)
+				return H_P4;
+		}
+	}
+	return H_SUCCESS;
+}
+
 /* Used to convert a nested guest real address to a L1 guest real address */
 static int kvmhv_translate_addr_nested(struct kvm_vcpu *vcpu,
 				       struct kvm_nested_guest *gp,
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 13999123b735..172a89187116 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -678,6 +678,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 		r = hv_enabled && kvmppc_hv_ops->enable_svm &&
 			!kvmppc_hv_ops->enable_svm(NULL);
 		break;
+	case KVM_CAP_PPC_RPT_INVALIDATE:
+		r = 1;
+		break;
 #endif
 	default:
 		r = 0;
diff --git a/arch/powerpc/mm/book3s64/radix_tlb.c b/arch/powerpc/mm/book3s64/radix_tlb.c
index b487b489d4b6..3a2b12d1d49b 100644
--- a/arch/powerpc/mm/book3s64/radix_tlb.c
+++ b/arch/powerpc/mm/book3s64/radix_tlb.c
@@ -18,10 +18,6 @@
 #include <asm/cputhreads.h>
 #include <asm/plpar_wrappers.h>
 
-#define RIC_FLUSH_TLB 0
-#define RIC_FLUSH_PWC 1
-#define RIC_FLUSH_ALL 2
-
 /*
  * tlbiel instruction for radix, set invalidation
  * i.e., r=1 and is=01 or is=10 or is=11
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index ca41220b40b8..c9ece825299e 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1053,6 +1053,7 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_X86_USER_SPACE_MSR 188
 #define KVM_CAP_X86_MSR_FILTER 189
 #define KVM_CAP_ENFORCE_PV_FEATURE_CPUID 190
+#define KVM_CAP_PPC_RPT_INVALIDATE 191
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
-- 
2.26.2