[Qemu-devel] [PATCH 2/5] virtio-ccw: Include standby memory when calculating storage increment

[Matthew Rosato <mjrosato@linux.vnet.ibm.com>]

When determining the memory increment size, include the standby
memory as well as the core memory.

Signed-off-by: Matthew Rosato <mjrosato@linux.vnet.ibm.com>
---
 hw/s390x/s390-virtio-ccw.c |   30 +++++++++++++++++++++++++-----
 target-s390x/cpu.h         |    4 ++++
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index 733d988..75deb24 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -17,6 +17,8 @@
 #include "css.h"
 #include "virtio-ccw.h"
 
+ram_addr_t pad_size;
+
 void io_subsystem_reset(void)
 {
     DeviceState *css, *sclp;
@@ -84,11 +86,22 @@ static void ccw_init(QEMUMachineInitArgs *args)
     int ret;
     VirtualCssBus *css_bus;
 
-    /* s390x ram size detection needs a 16bit multiplier + an increment. So
-       guests > 64GB can be specified in 2MB steps etc. */
-    while ((my_ram_size >> (20 + shift)) > 65535) {
-        shift++;
+    if (standby_mem_size) {
+        /* The storage increment size is a multiple of 1M and is a power of 2.
+         * The number of storage increments must be 1020 or fewer. */
+        while ((my_ram_size >> (20 + shift)) > 1020) {
+            shift++;
+        }
+        while ((standby_mem_size >> (20 + shift)) > 1020) {
+            shift++;
+        }
+        standby_mem_size = standby_mem_size >> (20 + shift) << (20 + shift);
+    } else {
+        while ((my_ram_size >> (20 + shift)) > 65535) {
+            shift++;
+        }
     }
+
     my_ram_size = my_ram_size >> (20 + shift) << (20 + shift);
 
     /* let's propagate the changed ram size into the global variable. */
@@ -103,11 +116,18 @@ static void ccw_init(QEMUMachineInitArgs *args)
     /* register hypercalls */
     virtio_ccw_register_hcalls();
 
-    /* allocate RAM */
+    /* allocate RAM for core */
     memory_region_init_ram(ram, NULL, "s390.ram", my_ram_size);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(sysmem, 0, ram);
 
+    if (standby_mem_size) {
+        if (my_ram_size % MEM_SECTION_SIZE) {
+            pad_size = MEM_SECTION_SIZE - my_ram_size % MEM_SECTION_SIZE;
+        }
+        my_ram_size += standby_mem_size + pad_size;
+    }
+
     /* allocate storage keys */
     storage_keys = g_malloc0(my_ram_size / TARGET_PAGE_SIZE);
 
diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h
index a2c077b..3383d55 100644
--- a/target-s390x/cpu.h
+++ b/target-s390x/cpu.h
@@ -385,6 +385,10 @@ unsigned s390_del_running_cpu(S390CPU *cpu);
 /* service interrupts are floating therefore we must not pass an cpustate */
 void s390_sclp_extint(uint32_t parm);
 
+/* from s390-virtio-ccw */
+#define MEM_SECTION_SIZE             0x10000000UL
+extern ram_addr_t standby_mem_size;
+
 /* from s390-virtio-bus */
 extern const hwaddr virtio_size;
 
-- 
1.7.9.5