L1 can reuest to get/set state of any of the supported Guest State
Buffer (GSB) elements using h_guest_[get|set]_state hcalls.
These hcalls needs to do some necessary validation check for each
get/set request based on the flags passed and operation supported.
Signed-off-by: Michael Neuling <mi...@neuling.org>
Signed-off-by: Harsh Prateek Bora <hars...@linux.ibm.com>
---
hw/ppc/spapr_nested.c | 267 ++++++++++++++++++++++++++++++++++
include/hw/ppc/spapr_nested.h | 22 +++
2 files changed, 289 insertions(+)
diff --git a/hw/ppc/spapr_nested.c b/hw/ppc/spapr_nested.c
index 6fbb1bcb02..498e7286fa 100644
--- a/hw/ppc/spapr_nested.c
+++ b/hw/ppc/spapr_nested.c
@@ -897,6 +897,138 @@ void init_nested(void)
}
}
+static struct guest_state_element *guest_state_element_next(
+ struct guest_state_element *element,
+ int64_t *len,
+ int64_t *num_elements)
+{
+ uint16_t size;
+
+ /* size is of element->value[] only. Not whole guest_state_element */
+ size = be16_to_cpu(element->size);
+
+ if (len) {
+ *len -= size + offsetof(struct guest_state_element, value);
+ }
+
+ if (num_elements) {
+ *num_elements -= 1;
+ }
+
+ return (struct guest_state_element *)(element->value + size);
+}
+
+static
+struct guest_state_element_type *guest_state_element_type_find(uint16_t id)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(guest_state_element_types); i++)
+ if (id == guest_state_element_types[i].id) {
+ return &guest_state_element_types[i];
+ }
+
+ return NULL;
+}
+
+static void print_element(struct guest_state_element *element,
+ struct guest_state_request *gsr)
+{
+ printf("id:0x%04x size:0x%04x %s ",
+ be16_to_cpu(element->id), be16_to_cpu(element->size),
+ gsr->flags & GUEST_STATE_REQUEST_SET ? "set" : "get");
+ printf("buf:0x%016lx ...\n", be64_to_cpu(*(uint64_t *)element->value));
+}
+
+static bool guest_state_request_check(struct guest_state_request *gsr)
+{
+ int64_t num_elements, len = gsr->len;
+ struct guest_state_buffer *gsb = gsr->gsb;
+ struct guest_state_element *element;
+ struct guest_state_element_type *type;
+ uint16_t id, size;
+
+ /* gsb->num_elements = 0 == 32 bits long */
+ assert(len >= 4);
+
+ num_elements = be32_to_cpu(gsb->num_elements);
+ element = gsb->elements;
+ len -= sizeof(gsb->num_elements);
+
+ /* Walk the buffer to validate the length */
+ while (num_elements) {
+
+ id = be16_to_cpu(element->id);
+ size = be16_to_cpu(element->size);
+
+ if (false) {
+ print_element(element, gsr);
+ }
+ /* buffer size too small */
+ if (len < 0) {
+ return false;
+ }
+
+ type = guest_state_element_type_find(id);
+ if (!type) {
+ printf("%s: Element ID %04x unknown\n", __func__, id);
+ print_element(element, gsr);
+ return false;
+ }
+
+ if (id == GSB_HV_VCPU_IGNORED_ID) {
+ goto next_element;
+ }
+
+ if (size != type->size) {
+ printf("%s: Size mismatch. Element ID:%04x. Size Exp:%i Got:%i\n",
+ __func__, id, type->size, size);
+ print_element(element, gsr);
+ return false;
+ }
+
+ if ((type->flags & GUEST_STATE_ELEMENT_TYPE_FLAG_READ_ONLY) &&
+ (gsr->flags & GUEST_STATE_REQUEST_SET)) {
+ printf("%s: trying to set a read-only Element ID:%04x.\n",
+ __func__, id);
+ return false;
+ }
+
+ if (type->flags & GUEST_STATE_ELEMENT_TYPE_FLAG_GUEST_WIDE) {
+ /* guest wide element type */
+ if (!(gsr->flags & GUEST_STATE_REQUEST_GUEST_WIDE)) {
+ printf("%s: trying to set a guest wide Element ID:%04x.\n",
+ __func__, id);
+ return false;
+ }
+ } else {
+ /* thread wide element type */
+ if (gsr->flags & GUEST_STATE_REQUEST_GUEST_WIDE) {
+ printf("%s: trying to set a thread wide Element ID:%04x.\n",
+ __func__, id);
+ return false;
+ }
+ }
+next_element:
+ element = guest_state_element_next(element, &len, &num_elements);
+
+ }
+ return true;
+}
+
+static bool is_gsr_invalid(struct guest_state_request *gsr,
+ struct guest_state_element *element,
+ struct guest_state_element_type *type)
+{
+ if ((gsr->flags & GUEST_STATE_REQUEST_SET) &&
+ (*(uint64_t *)(element->value) & ~(type->mask))) {
+ print_element(element, gsr);
+ printf("L1 can't set reserved bits (allowed mask: 0x%08lx)\n",
+ type->mask);
+ return true;
+ }
+ return false;
+}
static target_ulong h_guest_get_capabilities(PowerPCCPU *cpu,
SpaprMachineState *spapr,
@@ -1108,6 +1240,139 @@ static target_ulong h_guest_create_vcpu(PowerPCCPU *cpu,
return H_SUCCESS;
}
+static target_ulong getset_state(SpaprMachineStateNestedGuest *guest,
+ uint64_t vcpuid,
+ struct guest_state_request *gsr)
+{
+ void *ptr;
+ uint16_t id;
+ struct guest_state_element *element;
+ struct guest_state_element_type *type;
+ int64_t lenleft, num_elements;
+
+ lenleft = gsr->len;
+
+ if (!guest_state_request_check(gsr)) {
+ return H_P3;
+ }
+
+ num_elements = be32_to_cpu(gsr->gsb->num_elements);
+ element = gsr->gsb->elements;
+ /* Process the elements */
+ while (num_elements) {
+ type = NULL;
+ /* Debug print before doing anything */
+ if (false) {
+ print_element(element, gsr);
+ }
+
+ id = be16_to_cpu(element->id);
+ if (id == GSB_HV_VCPU_IGNORED_ID) {
+ goto next_element;
+ }
+
+ type = guest_state_element_type_find(id);
+ assert(type);
+
+ /* Get pointer to guest data to get/set */
+ if (type->location && type->copy) {
+ ptr = type->location(guest, vcpuid);
+ assert(ptr);
+ if (!~(type->mask) && is_gsr_invalid(gsr, element, type)) {
+ return H_INVALID_ELEMENT_VALUE;
+ }
+ type->copy(ptr + type->offset, element->value,
+ gsr->flags & GUEST_STATE_REQUEST_SET ? true : false);
+ }
+
+next_element:
+ element = guest_state_element_next(element, &lenleft, &num_elements);
+ }
+
+ return H_SUCCESS;
+}
+
+static target_ulong map_and_getset_state(PowerPCCPU *cpu,
+ SpaprMachineStateNestedGuest *guest,
+ uint64_t vcpuid,
+ struct guest_state_request *gsr)
+{
+ target_ulong rc;
+ int64_t lenleft, len;
+ bool is_write;
+
+ assert(gsr->len < (1024 * 1024)); /* sanity check */
+
+ lenleft = len = gsr->len;
+ gsr->gsb = address_space_map(CPU(cpu)->as, gsr->buf, (uint64_t *)&len,
+ false, MEMTXATTRS_UNSPECIFIED);
+ if (!gsr->gsb) {
+ rc = H_P3;
+ goto out1;
+ }
+
+ if (len != lenleft) {
+ rc = H_P3;
+ goto out1;
+ }
+
+ rc = getset_state(guest, vcpuid, gsr);
+
+out1:
+ is_write = (rc == H_SUCCESS) ? len : 0;
+ address_space_unmap(CPU(cpu)->as, gsr->gsb, len, is_write, false);
+ return rc;
+}
+
+static target_ulong h_guest_getset_state(PowerPCCPU *cpu,
+ SpaprMachineState *spapr,
+ target_ulong *args,
+ bool set)
+{
+ target_ulong flags = args[0];
+ target_ulong lpid = args[1];
+ target_ulong vcpuid = args[2];
+ target_ulong buf = args[3];
+ target_ulong buflen = args[4];
+ struct guest_state_request gsr;
+ SpaprMachineStateNestedGuest *guest;
+
+ guest = spapr_get_nested_guest(spapr, lpid);
+ if (!guest) {
+ return H_P2;
+ }
+ gsr.buf = buf;
+ gsr.len = buflen;
+ gsr.flags = 0;
+ if (flags & H_GUEST_GETSET_STATE_FLAG_GUEST_WIDE) {
+ gsr.flags |= GUEST_STATE_REQUEST_GUEST_WIDE;
+ }
+ if (flags & !H_GUEST_GETSET_STATE_FLAG_GUEST_WIDE) {
+ return H_PARAMETER; /* flag not supported yet */
+ }
+
+ if (set) {
+ gsr.flags |= GUEST_STATE_REQUEST_SET;
+ }
+ return map_and_getset_state(cpu, guest, vcpuid, &gsr);
+}
+
+static target_ulong h_guest_set_state(PowerPCCPU *cpu,
+ SpaprMachineState *spapr,
+ target_ulong opcode,
+ target_ulong *args)
+{
+ return h_guest_getset_state(cpu, spapr, args, true);
+}
+
+static target_ulong h_guest_get_state(PowerPCCPU *cpu,
+ SpaprMachineState *spapr,
+ target_ulong opcode,
+ target_ulong *args)
+{
+ return h_guest_getset_state(cpu, spapr, args, false);
+}
+
void spapr_register_nested(void)
{
spapr_register_hypercall(KVMPPC_H_SET_PARTITION_TABLE, h_set_ptbl);
@@ -1122,6 +1387,8 @@ void spapr_register_nested_phyp(void)
spapr_register_hypercall(H_GUEST_SET_CAPABILITIES,
h_guest_set_capabilities);
spapr_register_hypercall(H_GUEST_CREATE , h_guest_create);
spapr_register_hypercall(H_GUEST_CREATE_VCPU , h_guest_create_vcpu);
+ spapr_register_hypercall(H_GUEST_SET_STATE , h_guest_set_state);
+ spapr_register_hypercall(H_GUEST_GET_STATE , h_guest_get_state);
}
#else
diff --git a/include/hw/ppc/spapr_nested.h b/include/hw/ppc/spapr_nested.h
index 3c0d6a486e..eaee624b87 100644
--- a/include/hw/ppc/spapr_nested.h
+++ b/include/hw/ppc/spapr_nested.h
@@ -206,6 +206,9 @@
#define HVMASK_MSR 0xEBFFFFFFFFBFEFFF
#define HVMASK_HDEXCR 0x00000000FFFFFFFF
#define HVMASK_TB_OFFSET 0x000000FFFFFFFFFF
+#define H_GUEST_GETSET_STATE_FLAG_GUEST_WIDE 0x8000000000000000 /* BE in GSB */
+#define GUEST_STATE_REQUEST_GUEST_WIDE 0x1
+#define GUEST_STATE_REQUEST_SET 0x2
#define GUEST_STATE_ELEMENT(i, sz, s, f, ptr, c) { \
.id = (i), \
@@ -336,6 +339,25 @@ struct guest_state_element_type {
uint64_t mask;
};
+struct guest_state_element {
+ uint16_t id; /* Big Endian */
+ uint16_t size; /* Big Endian */
+ uint8_t value[]; /* Big Endian (based on size above) */
+} QEMU_PACKED;
+
+struct guest_state_buffer {
+ uint32_t num_elements; /* Big Endian */
+ struct guest_state_element elements[];
+} QEMU_PACKED;
+
+/* Actuall buffer plus some metadata about the request */
+struct guest_state_request {
+ struct guest_state_buffer *gsb;
+ int64_t buf;
+ int64_t len;
+ uint16_t flags;
+};
+
/*
* Register state for entering a nested guest with H_ENTER_NESTED.
* New member must be added at the end.
--
2.39.3
