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.

4 files changed, 8 insertions, 13 deletions

diff --git a/hw/m68k/an5206.c b/hw/m68k/an5206.c
index bed43a936d..846f4e40c6 100644
--- a/hw/m68k/an5206.c
+++ b/hw/m68k/an5206.c
@@ -33,7 +33,6 @@ static void an5206_init(MachineState *machine)
     uint64_t elf_entry;
     hwaddr entry;
     MemoryRegion *address_space_mem = get_system_memory();
-    MemoryRegion *ram = g_new(MemoryRegion, 1);
     MemoryRegion *sram = g_new(MemoryRegion, 1);
 
     cpu = M68K_CPU(cpu_create(machine->cpu_type));
@@ -46,8 +45,7 @@ static void an5206_init(MachineState *machine)
     env->rambar0 = AN5206_RAMBAR_ADDR | 1;
 
     /* DRAM at address zero */
-    memory_region_allocate_system_memory(ram, NULL, "an5206.ram", ram_size);
-    memory_region_add_subregion(address_space_mem, 0, ram);
+    memory_region_add_subregion(address_space_mem, 0, machine->ram);
 
     /* Internal SRAM.  */
     memory_region_init_ram(sram, NULL, "an5206.sram", 512, &error_fatal);
@@ -89,6 +87,7 @@ static void an5206_machine_init(MachineClass *mc)
     mc->desc = "Arnewsh 5206";
     mc->init = an5206_init;
     mc->default_cpu_type = M68K_CPU_TYPE_NAME("m5206");
+    mc->default_ram_id = "an5206.ram";
 }
 
 DEFINE_MACHINE("an5206", an5206_machine_init)
diff --git a/hw/m68k/mcf5208.c b/hw/m68k/mcf5208.c
index a999c21982..31622c71cb 100644
--- a/hw/m68k/mcf5208.c
+++ b/hw/m68k/mcf5208.c
@@ -234,7 +234,6 @@ static void mcf5208evb_init(MachineState *machine)
     qemu_irq *pic;
     MemoryRegion *address_space_mem = get_system_memory();
     MemoryRegion *rom = g_new(MemoryRegion, 1);
-    MemoryRegion *ram = g_new(MemoryRegion, 1);
     MemoryRegion *sram = g_new(MemoryRegion, 1);
 
     cpu = M68K_CPU(cpu_create(machine->cpu_type));
@@ -249,8 +248,7 @@ static void mcf5208evb_init(MachineState *machine)
     memory_region_add_subregion(address_space_mem, 0x00000000, rom);
 
     /* DRAM at 0x40000000 */
-    memory_region_allocate_system_memory(ram, NULL, "mcf5208.ram", ram_size);
-    memory_region_add_subregion(address_space_mem, 0x40000000, ram);
+    memory_region_add_subregion(address_space_mem, 0x40000000, machine->ram);
 
     /* Internal SRAM.  */
     memory_region_init_ram(sram, NULL, "mcf5208.sram", 16 * KiB, &error_fatal);
@@ -354,6 +352,7 @@ static void mcf5208evb_machine_init(MachineClass *mc)
     mc->init = mcf5208evb_init;
     mc->is_default = 1;
     mc->default_cpu_type = M68K_CPU_TYPE_NAME("m5208");
+    mc->default_ram_id = "mcf5208.ram";
 }
 
 DEFINE_MACHINE("mcf5208evb", mcf5208evb_machine_init)
diff --git a/hw/m68k/next-cube.c b/hw/m68k/next-cube.c
index 350c6fec78..14b99ed25d 100644
--- a/hw/m68k/next-cube.c
+++ b/hw/m68k/next-cube.c
@@ -860,7 +860,6 @@ static void next_cube_init(MachineState *machine)
 {
     M68kCPU *cpu;
     CPUM68KState *env;
-    MemoryRegion *ram = g_new(MemoryRegion, 1);
     MemoryRegion *rom = g_new(MemoryRegion, 1);
     MemoryRegion *mmiomem = g_new(MemoryRegion, 1);
     MemoryRegion *scrmem = g_new(MemoryRegion, 1);
@@ -893,8 +892,7 @@ static void next_cube_init(MachineState *machine)
     memcpy(ns->rtc.ram, rtc_ram2, 32);
 
     /* 64MB RAM starting at 0x04000000  */
-    memory_region_allocate_system_memory(ram, NULL, "next.ram", ram_size);
-    memory_region_add_subregion(sysmem, 0x04000000, ram);
+    memory_region_add_subregion(sysmem, 0x04000000, machine->ram);
 
     /* Framebuffer */
     dev = qdev_create(NULL, TYPE_NEXTFB);
@@ -967,6 +965,7 @@ static void next_machine_class_init(ObjectClass *oc, void *data)
     mc->desc = "NeXT Cube";
     mc->init = next_cube_init;
     mc->default_ram_size = RAM_SIZE;
+    mc->default_ram_id = "next.ram";
     mc->default_cpu_type = M68K_CPU_TYPE_NAME("m68040");
 }
 
diff --git a/hw/m68k/q800.c b/hw/m68k/q800.c
index 1e32363688..a4c4bc14cb 100644
--- a/hw/m68k/q800.c
+++ b/hw/m68k/q800.c
@@ -160,7 +160,6 @@ static void q800_init(MachineState *machine)
     ram_addr_t initrd_base;
     int32_t initrd_size;
     MemoryRegion *rom;
-    MemoryRegion *ram;
     MemoryRegion *io;
     const int io_slice_nb = (IO_SIZE / IO_SLICE) - 1;
     int i;
@@ -194,9 +193,7 @@ static void q800_init(MachineState *machine)
     qemu_register_reset(main_cpu_reset, cpu);
 
     /* RAM */
-    ram = g_malloc(sizeof(*ram));
-    memory_region_init_ram(ram, NULL, "m68k_mac.ram", ram_size, &error_abort);
-    memory_region_add_subregion(get_system_memory(), 0, ram);
+    memory_region_add_subregion(get_system_memory(), 0, machine->ram);
 
     /*
      * Memory from IO_BASE to IO_BASE + IO_SLICE is repeated
@@ -443,6 +440,7 @@ static void q800_machine_class_init(ObjectClass *oc, void *data)
     mc->max_cpus = 1;
     mc->is_default = 0;
     mc->block_default_type = IF_SCSI;
+    mc->default_ram_id = "m68k_mac.ram";
 }
 
 static const TypeInfo q800_machine_typeinfo = {