Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

[mirror_qemu.git] / backends / hostmem-file.c

diff --git a/backends/hostmem-file.c b/backends/hostmem-file.c
index 9b1b9f0a56043dc5788826c16fb9519f9fdf8370..361d4a8103ef82cba0994b24bc989a65798741ef 100644 (file)
--- a/backends/hostmem-file.c
+++ b/backends/hostmem-file.c
@@ -14,9 +14,12 @@
 #include "qapi/error.h"
 #include "qemu/error-report.h"
 #include "qemu/module.h"
+#include "qemu/madvise.h"
 #include "sysemu/hostmem.h"
 #include "qom/object_interfaces.h"
 #include "qom/object.h"
+#include "qapi/visitor.h"
+#include "qapi/qapi-visit-common.h"
 
 OBJECT_DECLARE_SIMPLE_TYPE(HostMemoryBackendFile, MEMORY_BACKEND_FILE)
 
@@ -26,9 +29,11 @@ struct HostMemoryBackendFile {
 
     char *mem_path;
     uint64_t align;
+    uint64_t offset;
     bool discard_data;
     bool is_pmem;
     bool readonly;
+    OnOffAuto rom;
 };
 
 static void
@@ -39,6 +44,7 @@ file_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
                object_get_typename(OBJECT(backend)));
 #else
     HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(backend);
+    uint32_t ram_flags;
     gchar *name;
 
     if (!backend->size) {
@@ -50,13 +56,39 @@ file_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
         return;
     }
 
+    switch (fb->rom) {
+    case ON_OFF_AUTO_AUTO:
+        /* Traditionally, opening the file readonly always resulted in ROM. */
+        fb->rom = fb->readonly ? ON_OFF_AUTO_ON : ON_OFF_AUTO_OFF;
+        break;
+    case ON_OFF_AUTO_ON:
+        if (!fb->readonly) {
+            error_setg(errp, "property 'rom' = 'on' is not supported with"
+                       " 'readonly' = 'off'");
+            return;
+        }
+        break;
+    case ON_OFF_AUTO_OFF:
+        if (fb->readonly && backend->share) {
+            error_setg(errp, "property 'rom' = 'off' is incompatible with"
+                       " 'readonly' = 'on' and 'share' = 'on'");
+            return;
+        }
+        break;
+    default:
+        assert(false);
+    }
+
     name = host_memory_backend_get_name(backend);
-    memory_region_init_ram_from_file(&backend->mr, OBJECT(backend),
-                                     name,
-                                     backend->size, fb->align,
-                                     (backend->share ? RAM_SHARED : 0) |
-                                     (fb->is_pmem ? RAM_PMEM : 0),
-                                     fb->mem_path, fb->readonly, errp);
+    ram_flags = backend->share ? RAM_SHARED : 0;
+    ram_flags |= fb->readonly ? RAM_READONLY_FD : 0;
+    ram_flags |= fb->rom == ON_OFF_AUTO_ON ? RAM_READONLY : 0;
+    ram_flags |= backend->reserve ? 0 : RAM_NORESERVE;
+    ram_flags |= fb->is_pmem ? RAM_PMEM : 0;
+    ram_flags |= RAM_NAMED_FILE;
+    memory_region_init_ram_from_file(&backend->mr, OBJECT(backend), name,
+                                     backend->size, fb->align, ram_flags,
+                                     fb->mem_path, fb->offset, errp);
     g_free(name);
 #endif
 }
@@ -123,6 +155,36 @@ static void file_memory_backend_set_align(Object *o, Visitor *v,
     fb->align = val;
 }
 
+static void file_memory_backend_get_offset(Object *o, Visitor *v,
+                                          const char *name, void *opaque,
+                                          Error **errp)
+{
+    HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o);
+    uint64_t val = fb->offset;
+
+    visit_type_size(v, name, &val, errp);
+}
+
+static void file_memory_backend_set_offset(Object *o, Visitor *v,
+                                          const char *name, void *opaque,
+                                          Error **errp)
+{
+    HostMemoryBackend *backend = MEMORY_BACKEND(o);
+    HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o);
+    uint64_t val;
+
+    if (host_memory_backend_mr_inited(backend)) {
+        error_setg(errp, "cannot change property '%s' of %s", name,
+                   object_get_typename(o));
+        return;
+    }
+
+    if (!visit_type_size(v, name, &val, errp)) {
+        return;
+    }
+    fb->offset = val;
+}
+
 #ifdef CONFIG_LIBPMEM
 static bool file_memory_backend_get_pmem(Object *o, Error **errp)
 {
@@ -166,6 +228,32 @@ static void file_memory_backend_set_readonly(Object *obj, bool value,
     fb->readonly = value;
 }
 
+static void file_memory_backend_get_rom(Object *obj, Visitor *v,
+                                        const char *name, void *opaque,
+                                        Error **errp)
+{
+    HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(obj);
+    OnOffAuto rom = fb->rom;
+
+    visit_type_OnOffAuto(v, name, &rom, errp);
+}
+
+static void file_memory_backend_set_rom(Object *obj, Visitor *v,
+                                        const char *name, void *opaque,
+                                        Error **errp)
+{
+    HostMemoryBackend *backend = MEMORY_BACKEND(obj);
+    HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(obj);
+
+    if (host_memory_backend_mr_inited(backend)) {
+        error_setg(errp, "cannot change property '%s' of %s.", name,
+                   object_get_typename(obj));
+        return;
+    }
+
+    visit_type_OnOffAuto(v, name, &fb->rom, errp);
+}
+
 static void file_backend_unparent(Object *obj)
 {
     HostMemoryBackend *backend = MEMORY_BACKEND(obj);
@@ -195,6 +283,12 @@ file_backend_class_init(ObjectClass *oc, void *data)
         file_memory_backend_get_align,
         file_memory_backend_set_align,
         NULL, NULL);
+    object_class_property_add(oc, "offset", "int",
+        file_memory_backend_get_offset,
+        file_memory_backend_set_offset,
+        NULL, NULL);
+    object_class_property_set_description(oc, "offset",
+        "Offset into the target file (ex: 1G)");
 #ifdef CONFIG_LIBPMEM
     object_class_property_add_bool(oc, "pmem",
         file_memory_backend_get_pmem, file_memory_backend_set_pmem);
@@ -202,6 +296,10 @@ file_backend_class_init(ObjectClass *oc, void *data)
     object_class_property_add_bool(oc, "readonly",
         file_memory_backend_get_readonly,
         file_memory_backend_set_readonly);
+    object_class_property_add(oc, "rom", "OnOffAuto",
+        file_memory_backend_get_rom, file_memory_backend_set_rom, NULL, NULL);
+    object_class_property_set_description(oc, "rom",
+        "Whether to create Read Only Memory (ROM)");
 }
 
 static void file_backend_instance_finalize(Object *o)