Merge tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu into...

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

diff --git a/backends/hostmem-file.c b/backends/hostmem-file.c
index cdabb412e699cf0a9cc6faa86adf8a4da51b96b2..b4335a80e6da7d9c654f2935916fc191cae1436d 100644 (file)
--- a/backends/hostmem-file.c
+++ b/backends/hostmem-file.c
@@ -14,22 +14,23 @@
 #include "qapi/error.h"
 #include "qemu/error-report.h"
 #include "qemu/module.h"
+#include "qemu/madvise.h"
 #include "sysemu/hostmem.h"
-#include "sysemu/sysemu.h"
 #include "qom/object_interfaces.h"
+#include "qom/object.h"
 
-#define MEMORY_BACKEND_FILE(obj) \
-    OBJECT_CHECK(HostMemoryBackendFile, (obj), TYPE_MEMORY_BACKEND_FILE)
+OBJECT_DECLARE_SIMPLE_TYPE(HostMemoryBackendFile, MEMORY_BACKEND_FILE)
 
-typedef struct HostMemoryBackendFile HostMemoryBackendFile;
 
 struct HostMemoryBackendFile {
     HostMemoryBackend parent_obj;
 
     char *mem_path;
     uint64_t align;
+    uint64_t offset;
     bool discard_data;
     bool is_pmem;
+    bool readonly;
 };
 
 static void
@@ -40,6 +41,7 @@ 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) {
@@ -52,12 +54,14 @@ file_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
     }
 
     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, errp);
+    ram_flags = backend->share ? RAM_SHARED : 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, fb->readonly,
+                                     errp);
     g_free(name);
 #endif
 }
@@ -110,25 +114,51 @@ static void file_memory_backend_set_align(Object *o, Visitor *v,
 {
     HostMemoryBackend *backend = MEMORY_BACKEND(o);
     HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o);
-    Error *local_err = NULL;
     uint64_t val;
 
     if (host_memory_backend_mr_inited(backend)) {
-        error_setg(&local_err, "cannot change property '%s' of %s",
-                   name, object_get_typename(o));
-        goto out;
+        error_setg(errp, "cannot change property '%s' of %s", name,
+                   object_get_typename(o));
+        return;
     }
 
-    visit_type_size(v, name, &val, &local_err);
-    if (local_err) {
-        goto out;
+    if (!visit_type_size(v, name, &val, errp)) {
+        return;
     }
     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;
+    }
 
- out:
-    error_propagate(errp, local_err);
+    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)
 {
     return MEMORY_BACKEND_FILE(o)->is_pmem;
@@ -140,26 +170,35 @@ static void file_memory_backend_set_pmem(Object *o, bool value, Error **errp)
     HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o);
 
     if (host_memory_backend_mr_inited(backend)) {
-
         error_setg(errp, "cannot change property 'pmem' of %s.",
                    object_get_typename(o));
         return;
     }
 
-#ifndef CONFIG_LIBPMEM
-    if (value) {
-        Error *local_err = NULL;
+    fb->is_pmem = value;
+}
+#endif /* CONFIG_LIBPMEM */
 
-        error_setg(&local_err,
-                   "Lack of libpmem support while setting the 'pmem=on'"
-                   " of %s. We can't ensure data persistence.",
-                   object_get_typename(o));
-        error_propagate(errp, local_err);
+static bool file_memory_backend_get_readonly(Object *obj, Error **errp)
+{
+    HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(obj);
+
+    return fb->readonly;
+}
+
+static void file_memory_backend_set_readonly(Object *obj, bool value,
+                                             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 'readonly' of %s.",
+                   object_get_typename(obj));
         return;
     }
-#endif
 
-    fb->is_pmem = value;
+    fb->readonly = value;
 }
 
 static void file_backend_unparent(Object *obj)
@@ -191,8 +230,19 @@ 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);
+#endif
+    object_class_property_add_bool(oc, "readonly",
+        file_memory_backend_get_readonly,
+        file_memory_backend_set_readonly);
 }
 
 static void file_backend_instance_finalize(Object *o)