[PATCH v6 4/6] KVM: PPC: Book3S HV: Nested support in H_RPT_INVALIDATE
Bharata B Rao
bharata at linux.ibm.com
Thu Mar 11 19:39:37 AEDT 2021
Enable support for process-scoped invalidations from nested
guests and partition-scoped invalidations for nested guests.
Process-scoped invalidations for any level of nested guests
are handled by implementing H_RPT_INVALIDATE handler in the
nested guest exit path in L0.
Partition-scoped invalidation requests are forwarded to the
right nested guest, handled there and passed down to L0
for eventual handling.
Signed-off-by: Bharata B Rao <bharata at linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.ibm.com>
[Nested guest partition-scoped invalidation changes]
---
arch/powerpc/include/asm/kvm_book3s.h | 3 +
arch/powerpc/kvm/book3s_hv.c | 71 +++++++++++++++++-
arch/powerpc/kvm/book3s_hv_nested.c | 104 ++++++++++++++++++++++++++
3 files changed, 175 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
index 2f5f919f6cd3..de8fc5a4d19c 100644
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -305,6 +305,9 @@ 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 do_h_rpt_invalidate_pat(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 5d008468347c..03755389efd1 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -922,6 +922,46 @@ static int kvmppc_get_yield_count(struct kvm_vcpu *vcpu)
return yield_count;
}
+/*
+ * H_RPT_INVALIDATE hcall handler for nested guests.
+ *
+ * Handles only nested process-scoped invalidation requests in L0.
+ */
+static int kvmppc_nested_h_rpt_invalidate(struct kvm_vcpu *vcpu)
+{
+ unsigned long type = kvmppc_get_gpr(vcpu, 6);
+ unsigned long pid, pg_sizes, start, end, psize;
+ struct kvm_nested_guest *gp;
+ struct mmu_psize_def *def;
+
+ /*
+ * The partition-scoped invalidations aren't handled here in L0.
+ */
+ if (type & H_RPTI_TYPE_NESTED)
+ return RESUME_HOST;
+
+ pid = kvmppc_get_gpr(vcpu, 4);
+ pg_sizes = kvmppc_get_gpr(vcpu, 7);
+ start = kvmppc_get_gpr(vcpu, 8);
+ end = kvmppc_get_gpr(vcpu, 9);
+
+ gp = kvmhv_get_nested(vcpu->kvm, vcpu->kvm->arch.lpid, false);
+ if (!gp)
+ goto out;
+
+ for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
+ def = &mmu_psize_defs[psize];
+ if (pg_sizes & def->h_rpt_pgsize)
+ do_h_rpt_invalidate_prt(pid, gp->shadow_lpid, type,
+ (1UL << def->shift), psize,
+ start, end);
+ }
+ kvmhv_put_nested(gp);
+out:
+ kvmppc_set_gpr(vcpu, 3, H_SUCCESS);
+ return RESUME_GUEST;
+}
+
static long kvmppc_h_rpt_invalidate(struct kvm_vcpu *vcpu,
unsigned long id, unsigned long target,
unsigned long type, unsigned long pg_sizes,
@@ -938,10 +978,18 @@ static long kvmppc_h_rpt_invalidate(struct kvm_vcpu *vcpu,
/*
* Partition-scoped invalidation for nested guests.
- * Not yet supported
*/
- if (type & H_RPTI_TYPE_NESTED)
- return H_P3;
+ 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 do_h_rpt_invalidate_pat(vcpu, id, type, pg_sizes,
+ start, end);
+ }
/*
* Process-scoped invalidation for L1 guests.
@@ -1636,6 +1684,23 @@ static int kvmppc_handle_nested_exit(struct kvm_vcpu *vcpu)
if (!xics_on_xive())
kvmppc_xics_rm_complete(vcpu, 0);
break;
+ case BOOK3S_INTERRUPT_SYSCALL:
+ {
+ unsigned long req = kvmppc_get_gpr(vcpu, 3);
+
+ /*
+ * The H_RPT_INVALIDATE hcalls issued by nested
+ * guests for process-scoped invalidations when
+ * GTSE=0, are handled here in L0.
+ */
+ if (req == H_RPT_INVALIDATE) {
+ r = kvmppc_nested_h_rpt_invalidate(vcpu);
+ break;
+ }
+
+ r = RESUME_HOST;
+ break;
+ }
default:
r = RESUME_HOST;
break;
diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c
index 0cd0e7aad588..adcc8e26ef22 100644
--- a/arch/powerpc/kvm/book3s_hv_nested.c
+++ b/arch/powerpc/kvm/book3s_hv_nested.c
@@ -1191,6 +1191,110 @@ 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, unsigned long ric)
+{
+ 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);
+ kvmhv_put_nested(gp);
+ }
+ return H_SUCCESS;
+}
+
+/*
+ * Performs partition-scoped invalidations for nested guests
+ * as part of H_RPT_INVALIDATE hcall.
+ */
+long do_h_rpt_invalidate_pat(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.
+ *
+ * However, 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 which happens in
+ * H_ENTER_NESTED call. Since we can't differentiate this case from
+ * the invalid case, we ignore such flush requests and return success.
+ */
+ gp = kvmhv_find_nested(vcpu->kvm, lpid);
+ if (!gp)
+ return H_SUCCESS;
+
+ /*
+ * A flush all request can be handled by a full lpid flush only.
+ */
+ if ((type & H_RPTI_TYPE_NESTED_ALL) == H_RPTI_TYPE_NESTED_ALL)
+ return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_ALL);
+
+#if 0
+ /*
+ * We don't need to handle a PWC flush like process table here,
+ * because intermediate partition scoped table in nested guest doesn't
+ * really have PWC. Only level we have PWC is in L0 and for nested
+ * invalidate at L0 we always do kvm_flush_lpid() which does
+ * radix__flush_all_lpid(). For range invalidate at any level, we
+ * are not removing the higher level page tables and hence there is
+ * no PWC invalidate needed.
+ */
+ if (type & H_RPTI_TYPE_PWC) {
+ ret = do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_PWC);
+ if (ret)
+ return H_P4;
+ }
+#endif
+
+ if (start == 0 && end == -1)
+ return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_TLB);
+
+ if (type & H_RPTI_TYPE_TLB) {
+ struct mmu_psize_def *def;
+
+ for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
+ def = &mmu_psize_defs[psize];
+ if (!(pg_sizes & def->h_rpt_pgsize))
+ continue;
+
+ ret = do_tlb_invalidate_nested_tlb(vcpu, lpid,
+ (1UL << def->shift),
+ 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,
--
2.26.2
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