[PATCH 08/15] ppc: spapr: Implement nested PAPR hcall - H_GUEST_CREATE

[Harsh Prateek Bora]

This hcall is used by L1 to indicate to L0 that a new nested guest needs
to be created and therefore necessary resource allocation shall be made.
The L0 uses a hash table for nested guest specific resource management.
This data structure is further utilized by other hcalls to operate on
related members during entire life cycle of the nested guest.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
---
 hw/ppc/spapr_nested.c         | 75 +++++++++++++++++++++++++++++++++++
 include/hw/ppc/spapr_nested.h |  3 ++
 2 files changed, 78 insertions(+)

diff --git a/hw/ppc/spapr_nested.c b/hw/ppc/spapr_nested.c
index 9af65f257f..09bbbfb341 100644
--- a/hw/ppc/spapr_nested.c
+++ b/hw/ppc/spapr_nested.c
@@ -444,6 +444,80 @@ static target_ulong h_guest_set_capabilities(PowerPCCPU 
*cpu,
     return H_SUCCESS;
 }
 
+static void
+destroy_guest_helper(gpointer value)
+{
+    struct SpaprMachineStateNestedGuest *guest = value;
+    g_free(guest);
+}
+
+static target_ulong h_guest_create(PowerPCCPU *cpu,
+                                   SpaprMachineState *spapr,
+                                   target_ulong opcode,
+                                   target_ulong *args)
+{
+    CPUPPCState *env = &cpu->env;
+    target_ulong flags = args[0];
+    target_ulong continue_token = args[1];
+    uint64_t lpid;
+    int nguests = 0;
+    struct SpaprMachineStateNestedGuest *guest;
+
+    if (flags) { /* don't handle any flags for now */
+        return H_UNSUPPORTED_FLAG;
+    }
+
+    if (continue_token != -1) {
+        return H_P2;
+    }
+
+    if (!spapr_get_cap(spapr, SPAPR_CAP_NESTED_PAPR)) {
+        return H_FUNCTION;
+    }
+
+    if (!spapr->nested.capabilities_set) {
+        return H_STATE;
+    }
+
+    if (!spapr->nested.guests) {
+        spapr->nested.lpid_max = NESTED_GUEST_MAX;
+        spapr->nested.guests = g_hash_table_new_full(NULL,
+                                                     NULL,
+                                                     NULL,
+                                                     destroy_guest_helper);
+    }
+
+    nguests = g_hash_table_size(spapr->nested.guests);
+
+    if (nguests == spapr->nested.lpid_max) {
+        return H_NO_MEM;
+    }
+
+    /* Lookup for available lpid */
+    for (lpid = 1; lpid < spapr->nested.lpid_max; lpid++) {
+        if (!(g_hash_table_lookup(spapr->nested.guests,
+                                  GINT_TO_POINTER(lpid)))) {
+            break;
+        }
+    }
+    if (lpid == spapr->nested.lpid_max) {
+        return H_NO_MEM;
+    }
+
+    guest = g_try_new0(struct SpaprMachineStateNestedGuest, 1);
+    if (!guest) {
+        return H_NO_MEM;
+    }
+
+    guest->pvr_logical = spapr->nested.pvr_base;
+
+    g_hash_table_insert(spapr->nested.guests, GINT_TO_POINTER(lpid), guest);
+    printf("%s: lpid: %lu (MAX: %i)\n", __func__, lpid, 
spapr->nested.lpid_max);
+
+    env->gpr[4] = lpid;
+    return H_SUCCESS;
+}
+
 void spapr_register_nested(void)
 {
     spapr_register_hypercall(KVMPPC_H_SET_PARTITION_TABLE, h_set_ptbl);
@@ -456,6 +530,7 @@ void spapr_register_nested_phyp(void)
 {
     spapr_register_hypercall(H_GUEST_GET_CAPABILITIES, 
h_guest_get_capabilities);
     spapr_register_hypercall(H_GUEST_SET_CAPABILITIES, 
h_guest_set_capabilities);
+    spapr_register_hypercall(H_GUEST_CREATE          , h_guest_create);
 }
 
 #else
diff --git a/include/hw/ppc/spapr_nested.h b/include/hw/ppc/spapr_nested.h
index a7996251cb..7841027df8 100644
--- a/include/hw/ppc/spapr_nested.h
+++ b/include/hw/ppc/spapr_nested.h
@@ -197,6 +197,9 @@
 #define H_GUEST_CAP_P9_MODE_BMAP    1
 #define H_GUEST_CAP_P10_MODE_BMAP   2
 
+/* Nested PAPR API macros */
+#define NESTED_GUEST_MAX 4096
+
 typedef struct SpaprMachineStateNestedGuest {
     unsigned long vcpus;
     struct SpaprMachineStateNestedGuestVcpu *vcpu;
-- 
2.39.3