spapr_iommu: Enable multiple TCE requests

Currently only single TCE entry per request is supported (H_PUT_TCE).
However PAPR+ specification allows multiple entry requests such as
H_PUT_TCE_INDIRECT and H_STUFF_TCE. Having less transitions to the host
kernel via ioctls, support of these calls can accelerate IOMMU operations.

This implements H_STUFF_TCE and H_PUT_TCE_INDIRECT.

This advertises "multi-tce" capability to the guest if the host kernel
supports it (KVM_CAP_SPAPR_MULTITCE) or guest is running in TCG mode.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>

2 files changed, 81 insertions, 0 deletions

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 39f196304d..8f612c9347 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -537,6 +537,9 @@ static void *spapr_create_fdt_skel(hwaddr initrd_base,
     /* RTAS */
     _FDT((fdt_begin_node(fdt, "rtas")));
 
+    if (!kvm_enabled() || kvmppc_spapr_use_multitce()) {
+        add_str(hypertas, "hcall-multi-tce");
+    }
     _FDT((fdt_property(fdt, "ibm,hypertas-functions", hypertas->str,
                        hypertas->len)));
     g_string_free(hypertas, TRUE);
diff --git a/hw/ppc/spapr_iommu.c b/hw/ppc/spapr_iommu.c
index 8c7382c289..b855e7ca6b 100644
--- a/hw/ppc/spapr_iommu.c
+++ b/hw/ppc/spapr_iommu.c
@@ -226,6 +226,82 @@ static target_ulong put_tce_emu(sPAPRTCETable *tcet, target_ulong ioba,
     return H_SUCCESS;
 }
 
+static target_ulong h_put_tce_indirect(PowerPCCPU *cpu,
+                                       sPAPREnvironment *spapr,
+                                       target_ulong opcode, target_ulong *args)
+{
+    int i;
+    target_ulong liobn = args[0];
+    target_ulong ioba = args[1];
+    target_ulong ioba1 = ioba;
+    target_ulong tce_list = args[2];
+    target_ulong npages = args[3];
+    target_ulong ret = H_PARAMETER;
+    sPAPRTCETable *tcet = spapr_tce_find_by_liobn(liobn);
+    CPUState *cs = CPU(cpu);
+
+    if (!tcet) {
+        return H_PARAMETER;
+    }
+
+    if (npages > 512) {
+        return H_PARAMETER;
+    }
+
+    ioba &= ~SPAPR_TCE_PAGE_MASK;
+    tce_list &= ~SPAPR_TCE_PAGE_MASK;
+
+    for (i = 0; i < npages; ++i, ioba += SPAPR_TCE_PAGE_SIZE) {
+        target_ulong tce = ldq_phys(cs->as, tce_list +
+                                    i * sizeof(target_ulong));
+        ret = put_tce_emu(tcet, ioba, tce);
+        if (ret) {
+            break;
+        }
+    }
+
+    /* Trace last successful or the first problematic entry */
+    i = i ? (i - 1) : 0;
+    trace_spapr_iommu_indirect(liobn, ioba1, tce_list, i,
+                               ldq_phys(cs->as,
+                               tce_list + i * sizeof(target_ulong)),
+                               ret);
+
+    return ret;
+}
+
+static target_ulong h_stuff_tce(PowerPCCPU *cpu, sPAPREnvironment *spapr,
+                              target_ulong opcode, target_ulong *args)
+{
+    int i;
+    target_ulong liobn = args[0];
+    target_ulong ioba = args[1];
+    target_ulong tce_value = args[2];
+    target_ulong npages = args[3];
+    target_ulong ret = H_PARAMETER;
+    sPAPRTCETable *tcet = spapr_tce_find_by_liobn(liobn);
+
+    if (!tcet) {
+        return H_PARAMETER;
+    }
+
+    if (npages > tcet->nb_table) {
+        return H_PARAMETER;
+    }
+
+    ioba &= ~SPAPR_TCE_PAGE_MASK;
+
+    for (i = 0; i < npages; ++i, ioba += SPAPR_TCE_PAGE_SIZE) {
+        ret = put_tce_emu(tcet, ioba, tce_value);
+        if (ret) {
+            break;
+        }
+    }
+    trace_spapr_iommu_stuff(liobn, ioba, tce_value, npages, ret);
+
+    return ret;
+}
+
 static target_ulong h_put_tce(PowerPCCPU *cpu, sPAPREnvironment *spapr,
                               target_ulong opcode, target_ulong *args)
 {
@@ -333,6 +409,8 @@ static void spapr_tce_table_class_init(ObjectClass *klass, void *data)
     /* hcall-tce */
     spapr_register_hypercall(H_PUT_TCE, h_put_tce);
     spapr_register_hypercall(H_GET_TCE, h_get_tce);
+    spapr_register_hypercall(H_PUT_TCE_INDIRECT, h_put_tce_indirect);
+    spapr_register_hypercall(H_STUFF_TCE, h_stuff_tce);
 }
 
 static TypeInfo spapr_tce_table_info = {