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-rw-r--r--qemu/hw/ppc/spapr_rng.c191
1 files changed, 191 insertions, 0 deletions
diff --git a/qemu/hw/ppc/spapr_rng.c b/qemu/hw/ppc/spapr_rng.c
new file mode 100644
index 000000000..80515eb54
--- /dev/null
+++ b/qemu/hw/ppc/spapr_rng.c
@@ -0,0 +1,191 @@
+/*
+ * QEMU sPAPR random number generator "device" for H_RANDOM hypercall
+ *
+ * Copyright 2015 Thomas Huth, Red Hat Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qemu-common.h"
+#include "cpu.h"
+#include "qemu/error-report.h"
+#include "sysemu/sysemu.h"
+#include "sysemu/device_tree.h"
+#include "sysemu/rng.h"
+#include "hw/ppc/spapr.h"
+#include "kvm_ppc.h"
+
+#define SPAPR_RNG(obj) \
+ OBJECT_CHECK(sPAPRRngState, (obj), TYPE_SPAPR_RNG)
+
+struct sPAPRRngState {
+ /*< private >*/
+ DeviceState ds;
+ RngBackend *backend;
+ bool use_kvm;
+};
+typedef struct sPAPRRngState sPAPRRngState;
+
+struct HRandomData {
+ QemuSemaphore sem;
+ union {
+ uint64_t v64;
+ uint8_t v8[8];
+ } val;
+ int received;
+};
+typedef struct HRandomData HRandomData;
+
+/* Callback function for the RngBackend */
+static void random_recv(void *dest, const void *src, size_t size)
+{
+ HRandomData *hrdp = dest;
+
+ if (src && size > 0) {
+ assert(size + hrdp->received <= sizeof(hrdp->val.v8));
+ memcpy(&hrdp->val.v8[hrdp->received], src, size);
+ hrdp->received += size;
+ }
+
+ qemu_sem_post(&hrdp->sem);
+}
+
+/* Handler for the H_RANDOM hypercall */
+static target_ulong h_random(PowerPCCPU *cpu, sPAPRMachineState *spapr,
+ target_ulong opcode, target_ulong *args)
+{
+ sPAPRRngState *rngstate;
+ HRandomData hrdata;
+
+ rngstate = SPAPR_RNG(object_resolve_path_type("", TYPE_SPAPR_RNG, NULL));
+
+ if (!rngstate || !rngstate->backend) {
+ return H_HARDWARE;
+ }
+
+ qemu_sem_init(&hrdata.sem, 0);
+ hrdata.val.v64 = 0;
+ hrdata.received = 0;
+
+ while (hrdata.received < 8) {
+ rng_backend_request_entropy(rngstate->backend, 8 - hrdata.received,
+ random_recv, &hrdata);
+ qemu_mutex_unlock_iothread();
+ qemu_sem_wait(&hrdata.sem);
+ qemu_mutex_lock_iothread();
+ }
+
+ qemu_sem_destroy(&hrdata.sem);
+ args[0] = hrdata.val.v64;
+
+ return H_SUCCESS;
+}
+
+static void spapr_rng_instance_init(Object *obj)
+{
+ sPAPRRngState *rngstate = SPAPR_RNG(obj);
+
+ if (object_resolve_path_type("", TYPE_SPAPR_RNG, NULL) != NULL) {
+ error_report("spapr-rng can not be instantiated twice!");
+ return;
+ }
+
+ object_property_add_link(obj, "rng", TYPE_RNG_BACKEND,
+ (Object **)&rngstate->backend,
+ object_property_allow_set_link,
+ OBJ_PROP_LINK_UNREF_ON_RELEASE, NULL);
+ object_property_set_description(obj, "rng",
+ "ID of the random number generator backend",
+ NULL);
+}
+
+static void spapr_rng_realize(DeviceState *dev, Error **errp)
+{
+
+ sPAPRRngState *rngstate = SPAPR_RNG(dev);
+
+ if (rngstate->use_kvm) {
+ if (kvmppc_enable_hwrng() == 0) {
+ return;
+ }
+ /*
+ * If user specified both, use-kvm and a backend, we fall back to
+ * the backend now. If not, provide an appropriate error message.
+ */
+ if (!rngstate->backend) {
+ error_setg(errp, "Could not initialize in-kernel H_RANDOM call!");
+ return;
+ }
+ }
+
+ if (rngstate->backend) {
+ spapr_register_hypercall(H_RANDOM, h_random);
+ } else {
+ error_setg(errp, "spapr-rng needs an RNG backend!");
+ }
+}
+
+int spapr_rng_populate_dt(void *fdt)
+{
+ int node;
+ int ret;
+
+ node = qemu_fdt_add_subnode(fdt, "/ibm,platform-facilities");
+ if (node <= 0) {
+ return -1;
+ }
+ ret = fdt_setprop_string(fdt, node, "device_type",
+ "ibm,platform-facilities");
+ ret |= fdt_setprop_cell(fdt, node, "#address-cells", 0x1);
+ ret |= fdt_setprop_cell(fdt, node, "#size-cells", 0x0);
+
+ node = fdt_add_subnode(fdt, node, "ibm,random-v1");
+ if (node <= 0) {
+ return -1;
+ }
+ ret |= fdt_setprop_string(fdt, node, "compatible", "ibm,random");
+
+ return ret ? -1 : 0;
+}
+
+static Property spapr_rng_properties[] = {
+ DEFINE_PROP_BOOL("use-kvm", sPAPRRngState, use_kvm, false),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void spapr_rng_class_init(ObjectClass *oc, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(oc);
+
+ dc->realize = spapr_rng_realize;
+ set_bit(DEVICE_CATEGORY_MISC, dc->categories);
+ dc->props = spapr_rng_properties;
+ dc->hotpluggable = false;
+}
+
+static const TypeInfo spapr_rng_info = {
+ .name = TYPE_SPAPR_RNG,
+ .parent = TYPE_DEVICE,
+ .instance_size = sizeof(sPAPRRngState),
+ .instance_init = spapr_rng_instance_init,
+ .class_init = spapr_rng_class_init,
+};
+
+static void spapr_rng_register_type(void)
+{
+ type_register_static(&spapr_rng_info);
+}
+type_init(spapr_rng_register_type)