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.

6 files changed, 46 insertions, 41 deletions

diff --git a/include/hw/boards.h b/include/hw/boards.h
index fb1b43d5b9..142b86d0ae 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -4,6 +4,7 @@
 #define HW_BOARDS_H
 
 #include "exec/memory.h"
+#include "sysemu/hostmem.h"
 #include "sysemu/blockdev.h"
 #include "sysemu/accel.h"
 #include "qapi/qapi-types-machine.h"
@@ -11,38 +12,6 @@
 #include "qom/object.h"
 #include "hw/core/cpu.h"
 
-/**
- * memory_region_allocate_system_memory - Allocate a board's main memory
- * @mr: the #MemoryRegion to be initialized
- * @owner: the object that tracks the region's reference count
- * @name: name of the memory region
- * @ram_size: size of the region in bytes
- *
- * This function allocates the main memory for a board model, and
- * initializes @mr appropriately. It also arranges for the memory
- * to be migrated (by calling vmstate_register_ram_global()).
- *
- * Memory allocated via this function will be backed with the memory
- * backend the user provided using "-mem-path" or "-numa node,memdev=..."
- * if appropriate; this is typically used to cause host huge pages to be
- * used. This function should therefore be called by a board exactly once,
- * for the primary or largest RAM area it implements.
- *
- * For boards where the major RAM is split into two parts in the memory
- * map, you can deal with this by calling memory_region_allocate_system_memory()
- * once to get a MemoryRegion with enough RAM for both parts, and then
- * creating alias MemoryRegions via memory_region_init_alias() which
- * alias into different parts of the RAM MemoryRegion and can be mapped
- * into the memory map in the appropriate places.
- *
- * Smaller pieces of memory (display RAM, static RAMs, etc) don't need
- * to be backed via the -mem-path memory backend and can simply
- * be created via memory_region_init_ram().
- */
-void memory_region_allocate_system_memory(MemoryRegion *mr, Object *owner,
-                                          const char *name,
-                                          uint64_t ram_size);
-
 #define TYPE_MACHINE_SUFFIX "-machine"
 
 /* Machine class name that needs to be used for class-name-based machine
@@ -72,7 +41,12 @@ void machine_set_cpu_numa_node(MachineState *machine,
                                Error **errp);
 
 void machine_class_allow_dynamic_sysbus_dev(MachineClass *mc, const char *type);
-
+/*
+ * Checks that backend isn't used, preps it for exclusive usage and
+ * returns migratable MemoryRegion provided by backend.
+ */
+MemoryRegion *machine_consume_memdev(MachineState *machine,
+                                     HostMemoryBackend *backend);
 
 /**
  * CPUArchId:
@@ -169,6 +143,13 @@ typedef struct {
  *    false is returned, an error must be set to show the reason of
  *    the rejection.  If the hook is not provided, all hotplug will be
  *    allowed.
+ * @default_ram_id:
+ *    Specifies inital RAM MemoryRegion name to be used for default backend
+ *    creation if user explicitly hasn't specified backend with "memory-backend"
+ *    property.
+ *    It also will be used as a way to optin into "-m" option support.
+ *    If it's not set by board, '-m' will be ignored and generic code will
+ *    not create default RAM MemoryRegion.
  */
 struct MachineClass {
     /*< private >*/
@@ -225,6 +206,7 @@ struct MachineClass {
     bool nvdimm_supported;
     bool numa_mem_supported;
     bool auto_enable_numa;
+    const char *default_ram_id;
 
     HotplugHandler *(*get_hotplug_handler)(MachineState *machine,
                                            DeviceState *dev);
@@ -285,6 +267,12 @@ struct MachineState {
     bool enforce_config_section;
     bool enable_graphics;
     char *memory_encryption;
+    char *ram_memdev_id;
+    /*
+     * convenience alias to ram_memdev_id backend memory region
+     * or to numa container memory region
+     */
+    MemoryRegion *ram;
     DeviceMemoryState *device_memory;
 
     ram_addr_t ram_size;
diff --git a/include/hw/misc/aspeed_sdmc.h b/include/hw/misc/aspeed_sdmc.h
index 5dbde59fe7..cea1e67fe3 100644
--- a/include/hw/misc/aspeed_sdmc.h
+++ b/include/hw/misc/aspeed_sdmc.h
@@ -40,6 +40,7 @@ typedef struct AspeedSDMCClass {
     SysBusDeviceClass parent_class;
 
     uint64_t max_ram_size;
+    const uint64_t *valid_ram_sizes;
     uint32_t (*compute_conf)(AspeedSDMCState *s, uint32_t data);
     void (*write)(AspeedSDMCState *s, uint32_t reg, uint32_t data);
 } AspeedSDMCClass;
diff --git a/include/hw/ppc/ppc4xx.h b/include/hw/ppc/ppc4xx.h
index 7d82259051..cc19c8da5b 100644
--- a/include/hw/ppc/ppc4xx.h
+++ b/include/hw/ppc/ppc4xx.h
@@ -42,11 +42,10 @@ enum {
 qemu_irq *ppcuic_init (CPUPPCState *env, qemu_irq *irqs,
                        uint32_t dcr_base, int has_ssr, int has_vr);
 
-ram_addr_t ppc4xx_sdram_adjust(ram_addr_t ram_size, int nr_banks,
-                               MemoryRegion ram_memories[],
-                               hwaddr ram_bases[],
-                               hwaddr ram_sizes[],
-                               const ram_addr_t sdram_bank_sizes[]);
+void ppc4xx_sdram_banks(MemoryRegion *ram, int nr_banks,
+                        MemoryRegion ram_memories[],
+                        hwaddr ram_bases[], hwaddr ram_sizes[],
+                        const ram_addr_t sdram_bank_sizes[]);
 
 void ppc4xx_sdram_init (CPUPPCState *env, qemu_irq irq, int nbanks,
                         MemoryRegion ram_memories[],
diff --git a/include/sysemu/hostmem.h b/include/sysemu/hostmem.h
index 4dbdadd39e..8276e53683 100644
--- a/include/sysemu/hostmem.h
+++ b/include/sysemu/hostmem.h
@@ -27,6 +27,22 @@
 #define MEMORY_BACKEND_CLASS(klass) \
     OBJECT_CLASS_CHECK(HostMemoryBackendClass, (klass), TYPE_MEMORY_BACKEND)
 
+/* hostmem-ram.c */
+/**
+ * @TYPE_MEMORY_BACKEND_RAM:
+ * name of backend that uses mmap on the anonymous RAM
+ */
+
+#define TYPE_MEMORY_BACKEND_RAM "memory-backend-ram"
+
+/* hostmem-file.c */
+/**
+ * @TYPE_MEMORY_BACKEND_FILE:
+ * name of backend that uses mmap on a file descriptor
+ */
+#define TYPE_MEMORY_BACKEND_FILE "memory-backend-file"
+
+typedef struct HostMemoryBackend HostMemoryBackend;
 typedef struct HostMemoryBackendClass HostMemoryBackendClass;
 
 /**
@@ -45,6 +61,7 @@ struct HostMemoryBackendClass {
  * @parent: opaque parent object container
  * @size: amount of memory backend provides
  * @mr: MemoryRegion representing host memory belonging to backend
+ * @prealloc_threads: number of threads to be used for preallocatining RAM
  */
 struct HostMemoryBackend {
     /* private */
@@ -53,7 +70,8 @@ struct HostMemoryBackend {
     /* protected */
     uint64_t size;
     bool merge, dump, use_canonical_path;
-    bool prealloc, force_prealloc, is_mapped, share;
+    bool prealloc, is_mapped, share;
+    uint32_t prealloc_threads;
     DECLARE_BITMAP(host_nodes, MAX_NODES + 1);
     HostMemPolicy policy;
 
diff --git a/include/sysemu/numa.h b/include/sysemu/numa.h
index ba693cc80b..ad58ee88f7 100644
--- a/include/sysemu/numa.h
+++ b/include/sysemu/numa.h
@@ -112,5 +112,6 @@ void numa_default_auto_assign_ram(MachineClass *mc, NodeInfo *nodes,
                                   int nb_nodes, ram_addr_t size);
 void numa_cpu_pre_plug(const struct CPUArchId *slot, DeviceState *dev,
                        Error **errp);
+bool numa_uses_legacy_mem(void);
 
 #endif
diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h
index dec64fcc17..479d90bcea 100644
--- a/include/sysemu/sysemu.h
+++ b/include/sysemu/sysemu.h
@@ -50,8 +50,6 @@ extern uint8_t *boot_splash_filedata;
 extern bool enable_mlock;
 extern bool enable_cpu_pm;
 extern QEMUClockType rtc_clock;
-extern const char *mem_path;
-extern int mem_prealloc;
 
 #define MAX_OPTION_ROMS 16
 typedef struct QEMUOptionRom {