Patchwork [2/3] pseries: Allow KVM Book3S-HV on PPC970 CPUS

diff --git a/hw/spapr.c b/hw/spapr.c
index ba9ae1c..d51425a 100644
--- a/hw/spapr.c
+++ b/hw/spapr.c
@@ -89,6 +89,7 @@  qemu_irq spapr_allocate_irq(uint32_t hint, uint32_t *irq_num)
 }
 
 static void *spapr_create_fdt_skel(const char *cpu_model,
+                                   target_phys_addr_t rma_size,
                                    target_phys_addr_t initrd_base,
                                    target_phys_addr_t initrd_size,
                                    const char *boot_device,
@@ -97,7 +98,9 @@  static void *spapr_create_fdt_skel(const char *cpu_model,
 {
     void *fdt;
     CPUState *env;
-    uint64_t mem_reg_property[] = { 0, cpu_to_be64(ram_size) };
+    uint64_t mem_reg_property_rma[] = { 0, cpu_to_be64(rma_size) };
+    uint64_t mem_reg_property_nonrma[] = { cpu_to_be64(rma_size),
+                                           cpu_to_be64(ram_size - rma_size) };
     uint32_t start_prop = cpu_to_be32(initrd_base);
     uint32_t end_prop = cpu_to_be32(initrd_base + initrd_size);
     uint32_t pft_size_prop[] = {0, cpu_to_be32(hash_shift)};
@@ -143,15 +146,25 @@  static void *spapr_create_fdt_skel(const char *cpu_model,
 
     _FDT((fdt_end_node(fdt)));
 
-    /* memory node */
+    /* memory node(s) */
     _FDT((fdt_begin_node(fdt, "memory@0")));
 
     _FDT((fdt_property_string(fdt, "device_type", "memory")));
-    _FDT((fdt_property(fdt, "reg",
-                       mem_reg_property, sizeof(mem_reg_property))));
-
+    _FDT((fdt_property(fdt, "reg", mem_reg_property_rma,
+                       sizeof(mem_reg_property_rma))));
     _FDT((fdt_end_node(fdt)));
 
+    if (ram_size > rma_size) {
+        char mem_name[32];
+
+	sprintf(mem_name, "memory@%" PRIx64, (uint64_t)rma_size);
+	_FDT((fdt_begin_node(fdt, mem_name)));
+	_FDT((fdt_property_string(fdt, "device_type", "memory")));
+        _FDT((fdt_property(fdt, "reg", mem_reg_property_nonrma,
+                           sizeof(mem_reg_property_nonrma))));
+        _FDT((fdt_end_node(fdt)));
+    }        
+
     /* cpus */
     _FDT((fdt_begin_node(fdt, "cpus")));
 
@@ -341,6 +354,7 @@  static void ppc_spapr_init(ram_addr_t ram_size,
 {
     CPUState *env;
     int i;
+    target_phys_addr_t rma_alloc_size, rma_size;
     ram_addr_t ram_offset;
     uint32_t initrd_base;
     long kernel_size, initrd_size, fw_size;
@@ -350,10 +364,23 @@  static void ppc_spapr_init(ram_addr_t ram_size,
     spapr = g_malloc(sizeof(*spapr));
     cpu_ppc_hypercall = emulate_spapr_hypercall;
 
+    /* Allocate RMA if necessary */
+    rma_alloc_size = kvmppc_alloc_rma("ppc_spapr.rma");
+
+    if (rma_alloc_size == -1) {
+        hw_error("qemu: Unable to create RMA\n");
+        exit(1);
+    }
+    if (rma_alloc_size && (rma_alloc_size < ram_size)) {
+        rma_size = rma_alloc_size;
+    } else {
+        rma_size = ram_size;
+    }
+
     /* We place the device tree just below either the top of RAM, or
      * 2GB, so that it can be processed with 32-bit code if
      * necessary */
-    spapr->fdt_addr = MIN(ram_size, 0x80000000) - FDT_MAX_SIZE;
+    spapr->fdt_addr = MIN(rma_size, 0x80000000) - FDT_MAX_SIZE;
     spapr->rtas_addr = spapr->fdt_addr - RTAS_MAX_SIZE;
 
     /* init CPUs */
@@ -378,8 +405,13 @@  static void ppc_spapr_init(ram_addr_t ram_size,
 
     /* allocate RAM */
     spapr->ram_limit = ram_size;
-    ram_offset = qemu_ram_alloc(NULL, "ppc_spapr.ram", spapr->ram_limit);
-    cpu_register_physical_memory(0, ram_size, ram_offset);
+    if (spapr->ram_limit > rma_alloc_size) {
+        ram_addr_t nonrma_base = rma_alloc_size;
+        ram_addr_t nonrma_size = spapr->ram_limit - rma_alloc_size;
+
+        ram_offset = qemu_ram_alloc(NULL, "ppc_spapr.ram", nonrma_size);
+        cpu_register_physical_memory(nonrma_base, nonrma_size, ram_offset);
+    }
 
     /* allocate hash page table.  For now we always make this 16mb,
      * later we should probably make it scale to the size of guest
@@ -503,7 +535,7 @@  static void ppc_spapr_init(ram_addr_t ram_size,
     }
 
     /* Prepare the device tree */
-    spapr->fdt_skel = spapr_create_fdt_skel(cpu_model,
+    spapr->fdt_skel = spapr_create_fdt_skel(cpu_model, rma_size,
                                             initrd_base, initrd_size,
                                             boot_device, kernel_cmdline,
                                             pteg_shift + 7);
diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c
index 2c1bc7a..37ee902 100644
--- a/target-ppc/kvm.c
+++ b/target-ppc/kvm.c
@@ -55,6 +55,9 @@  static int cap_interrupt_level = false;
 static int cap_segstate;
 static int cap_booke_sregs;
 static int cap_ppc_smt = 0;
+#ifdef KVM_CAP_PPC_RMA
+static int cap_ppc_rma = 0;
+#endif
 
 /* XXX We have a race condition where we actually have a level triggered
  *     interrupt, but the infrastructure can't expose that yet, so the guest
@@ -81,6 +84,9 @@  int kvm_arch_init(KVMState *s)
 #ifdef KVM_CAP_PPC_SMT
     cap_ppc_smt = kvm_check_extension(s, KVM_CAP_PPC_SMT);
 #endif
+#ifdef KVM_CAP_PPC_RMA
+    cap_ppc_rma = kvm_check_extension(s, KVM_CAP_PPC_RMA);
+#endif
 
     if (!cap_interrupt_level) {
         fprintf(stderr, "KVM: Couldn't find level irq capability. Expect the "
@@ -741,6 +747,51 @@  int kvmppc_smt_threads(void)
     return cap_ppc_smt ? cap_ppc_smt : 1;
 }
 
+off_t kvmppc_alloc_rma(const char *name)
+{
+#ifndef KVM_CAP_PPC_RMA
+    return 0;
+#else
+    void *rma;
+    ram_addr_t rma_offset;
+    off_t size;
+    int fd;
+    struct kvm_allocate_rma ret;
+
+    /* If cap_ppc_rma == 0, contiguous RMA allocation is not supported
+     * if cap_ppc_rma == 1, contiguous RMA allocation is supported, but
+     *                      not necessary on this hardware
+     * if cap_ppc_rma == 2, contiguous RMA allocation is needed on this hardware
+     *
+     * FIXME: We should allow the user to force contiguous RMA
+     * allocation in the cap_ppc_rma==1 case.
+     */
+    if (cap_ppc_rma < 2) {
+        return 0;
+    }
+
+    fd = kvm_vm_ioctl(kvm_state, KVM_ALLOCATE_RMA, &ret);
+    if (fd < 0) {
+        fprintf(stderr, "KVM: Error on KVM_ALLOCATE_RMA: %s\n",
+                strerror(errno));
+        return -1;
+    }
+
+    size = MIN(ret.rma_size, 256ul << 20);
+
+    rma = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+    if (rma == MAP_FAILED) {
+        fprintf(stderr, "KVM: Error mapping RMA: %s\n", strerror(errno));
+        return -1;
+    };
+
+    rma_offset = qemu_ram_alloc_from_ptr(NULL, name, size, rma);
+    cpu_register_physical_memory(0, size, rma_offset);
+
+    return size;
+#endif
+}
+
 bool kvm_arch_stop_on_emulation_error(CPUState *env)
 {
     return true;
diff --git a/target-ppc/kvm_ppc.h b/target-ppc/kvm_ppc.h
index c298411..ad9903c 100644
--- a/target-ppc/kvm_ppc.h
+++ b/target-ppc/kvm_ppc.h
@@ -19,6 +19,7 @@  int kvmppc_get_hypercall(CPUState *env, uint8_t *buf, int buf_len);
 int kvmppc_set_interrupt(CPUState *env, int irq, int level);
 void kvmppc_set_papr(CPUState *env);
 int kvmppc_smt_threads(void);
+off_t kvmppc_alloc_rma(const char *name);
 
 #else
 
@@ -51,6 +52,11 @@  static inline int kvmppc_smt_threads(void)
     return 1;
 }
 
+static inline off_t kvmppc_alloc_rma(const char *name)
+{
+    return 0;
+}
+
 #endif
 
 #ifndef CONFIG_KVM