Merge tag 'patchew/20200219160953.13771-1-imammedo@redhat.com' of https://github.com/patchew-project/qemu into HEAD

This series removes ad hoc RAM allocation API (memory_region_allocate_system_memory)
and consolidates it around hostmem backend. It allows to

* resolve conflicts between global -mem-prealloc and hostmem's "policy" option,
  fixing premature allocation before binding policy is applied

* simplify complicated memory allocation routines which had to deal with 2 ways
  to allocate RAM.

* reuse hostmem backends of a choice for main RAM without adding extra CLI
  options to duplicate hostmem features.  A recent case was -mem-shared, to
  enable vhost-user on targets that don't support hostmem backends [1] (ex: s390)

* move RAM allocation from individual boards into generic machine code and
  provide them with prepared MemoryRegion.

* clean up deprecated NUMA features which were tied to the old API (see patches)
  - "numa: remove deprecated -mem-path fallback to anonymous RAM"
  - (POSTPONED, waiting on libvirt side) "forbid '-numa node,mem' for 5.0 and newer machine types"
  - (POSTPONED) "numa: remove deprecated implicit RAM distribution between nodes"

Introduce a new machine.memory-backend property and wrapper code that aliases
global -mem-path and -mem-alloc into automatically created hostmem backend
properties (provided memory-backend was not set explicitly given by user).
A bulk of trivial patches then follow to incrementally convert individual
boards to using machine.memory-backend provided MemoryRegion.

Board conversion typically involves:

* providing MachineClass::default_ram_size and MachineClass::default_ram_id
  so generic code could create default backend if user didn't explicitly provide
  memory-backend or -m options

* dropping memory_region_allocate_system_memory() call

* using convenience MachineState::ram MemoryRegion, which points to MemoryRegion
   allocated by ram-memdev

On top of that for some boards:

* missing ram_size checks are added (typically it were boards with fixed ram size)

* ram_size fixups are replaced by checks and hard errors, forcing user to
  provide correct "-m" values instead of ignoring it and continuing running.

After all boards are converted, the old API is removed and memory allocation
routines are cleaned up.

1 files changed, 5 insertions, 9 deletions

diff --git a/hw/arm/vexpress.c b/hw/arm/vexpress.c
index 4673a88a8d..ed683eeea5 100644
--- a/hw/arm/vexpress.c
+++ b/hw/arm/vexpress.c
@@ -273,7 +273,6 @@ static void a9_daughterboard_init(const VexpressMachineState *vms,
 {
     MachineState *machine = MACHINE(vms);
     MemoryRegion *sysmem = get_system_memory();
-    MemoryRegion *ram = g_new(MemoryRegion, 1);
     MemoryRegion *lowram = g_new(MemoryRegion, 1);
     ram_addr_t low_ram_size;
 
@@ -283,8 +282,6 @@ static void a9_daughterboard_init(const VexpressMachineState *vms,
         exit(1);
     }
 
-    memory_region_allocate_system_memory(ram, NULL, "vexpress.highmem",
-                                         ram_size);
     low_ram_size = ram_size;
     if (low_ram_size > 0x4000000) {
         low_ram_size = 0x4000000;
@@ -293,9 +290,10 @@ static void a9_daughterboard_init(const VexpressMachineState *vms,
      * address space should in theory be remappable to various
      * things including ROM or RAM; we always map the RAM there.
      */
-    memory_region_init_alias(lowram, NULL, "vexpress.lowmem", ram, 0, low_ram_size);
+    memory_region_init_alias(lowram, NULL, "vexpress.lowmem", machine->ram,
+                             0, low_ram_size);
     memory_region_add_subregion(sysmem, 0x0, lowram);
-    memory_region_add_subregion(sysmem, 0x60000000, ram);
+    memory_region_add_subregion(sysmem, 0x60000000, machine->ram);
 
     /* 0x1e000000 A9MPCore (SCU) private memory region */
     init_cpus(machine, cpu_type, TYPE_A9MPCORE_PRIV, 0x1e000000, pic,
@@ -360,7 +358,6 @@ static void a15_daughterboard_init(const VexpressMachineState *vms,
 {
     MachineState *machine = MACHINE(vms);
     MemoryRegion *sysmem = get_system_memory();
-    MemoryRegion *ram = g_new(MemoryRegion, 1);
     MemoryRegion *sram = g_new(MemoryRegion, 1);
 
     {
@@ -375,10 +372,8 @@ static void a15_daughterboard_init(const VexpressMachineState *vms,
         }
     }
 
-    memory_region_allocate_system_memory(ram, NULL, "vexpress.highmem",
-                                         ram_size);
     /* RAM is from 0x80000000 upwards; there is no low-memory alias for it. */
-    memory_region_add_subregion(sysmem, 0x80000000, ram);
+    memory_region_add_subregion(sysmem, 0x80000000, machine->ram);
 
     /* 0x2c000000 A15MPCore private memory region (GIC) */
     init_cpus(machine, cpu_type, TYPE_A15MPCORE_PRIV,
@@ -795,6 +790,7 @@ static void vexpress_class_init(ObjectClass *oc, void *data)
     mc->init = vexpress_common_init;
     mc->max_cpus = 4;
     mc->ignore_memory_transaction_failures = true;
+    mc->default_ram_id = "vexpress.highmem";
 }
 
 static void vexpress_a9_class_init(ObjectClass *oc, void *data)