Marc-André Lureau | dbb9e0f | 2018-02-01 14:27:54 +0100 | [diff] [blame] | 1 | /* |
| 2 | * QEMU host memfd memory backend |
| 3 | * |
| 4 | * Copyright (C) 2018 Red Hat Inc |
| 5 | * |
| 6 | * Authors: |
| 7 | * Marc-André Lureau <marcandre.lureau@redhat.com> |
| 8 | * |
| 9 | * This work is licensed under the terms of the GNU GPL, version 2 or later. |
| 10 | * See the COPYING file in the top-level directory. |
| 11 | */ |
| 12 | #include "qemu/osdep.h" |
| 13 | #include "qemu-common.h" |
| 14 | #include "sysemu/hostmem.h" |
| 15 | #include "sysemu/sysemu.h" |
| 16 | #include "qom/object_interfaces.h" |
| 17 | #include "qemu/memfd.h" |
| 18 | #include "qapi/error.h" |
| 19 | |
| 20 | #define TYPE_MEMORY_BACKEND_MEMFD "memory-backend-memfd" |
| 21 | |
| 22 | #define MEMORY_BACKEND_MEMFD(obj) \ |
| 23 | OBJECT_CHECK(HostMemoryBackendMemfd, (obj), TYPE_MEMORY_BACKEND_MEMFD) |
| 24 | |
| 25 | typedef struct HostMemoryBackendMemfd HostMemoryBackendMemfd; |
| 26 | |
| 27 | struct HostMemoryBackendMemfd { |
| 28 | HostMemoryBackend parent_obj; |
| 29 | |
| 30 | bool hugetlb; |
| 31 | uint64_t hugetlbsize; |
| 32 | bool seal; |
| 33 | }; |
| 34 | |
| 35 | static void |
| 36 | memfd_backend_memory_alloc(HostMemoryBackend *backend, Error **errp) |
| 37 | { |
| 38 | HostMemoryBackendMemfd *m = MEMORY_BACKEND_MEMFD(backend); |
| 39 | char *name; |
| 40 | int fd; |
| 41 | |
| 42 | if (!backend->size) { |
| 43 | error_setg(errp, "can't create backend with size 0"); |
| 44 | return; |
| 45 | } |
| 46 | |
Marc-André Lureau | dbb9e0f | 2018-02-01 14:27:54 +0100 | [diff] [blame] | 47 | backend->force_prealloc = mem_prealloc; |
| 48 | fd = qemu_memfd_create(TYPE_MEMORY_BACKEND_MEMFD, backend->size, |
| 49 | m->hugetlb, m->hugetlbsize, m->seal ? |
| 50 | F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL : 0, |
| 51 | errp); |
| 52 | if (fd == -1) { |
| 53 | return; |
| 54 | } |
| 55 | |
Marc-André Lureau | fa0cb34 | 2018-09-12 16:18:00 +0400 | [diff] [blame] | 56 | name = host_memory_backend_get_name(backend); |
Marc-André Lureau | dbb9e0f | 2018-02-01 14:27:54 +0100 | [diff] [blame] | 57 | memory_region_init_ram_from_fd(&backend->mr, OBJECT(backend), |
Marc-André Lureau | 36ea397 | 2018-08-28 17:38:40 +0200 | [diff] [blame] | 58 | name, backend->size, |
| 59 | backend->share, fd, errp); |
Marc-André Lureau | dbb9e0f | 2018-02-01 14:27:54 +0100 | [diff] [blame] | 60 | g_free(name); |
| 61 | } |
| 62 | |
| 63 | static bool |
| 64 | memfd_backend_get_hugetlb(Object *o, Error **errp) |
| 65 | { |
| 66 | return MEMORY_BACKEND_MEMFD(o)->hugetlb; |
| 67 | } |
| 68 | |
| 69 | static void |
| 70 | memfd_backend_set_hugetlb(Object *o, bool value, Error **errp) |
| 71 | { |
| 72 | MEMORY_BACKEND_MEMFD(o)->hugetlb = value; |
| 73 | } |
| 74 | |
| 75 | static void |
| 76 | memfd_backend_set_hugetlbsize(Object *obj, Visitor *v, const char *name, |
| 77 | void *opaque, Error **errp) |
| 78 | { |
| 79 | HostMemoryBackendMemfd *m = MEMORY_BACKEND_MEMFD(obj); |
| 80 | Error *local_err = NULL; |
| 81 | uint64_t value; |
| 82 | |
| 83 | if (host_memory_backend_mr_inited(MEMORY_BACKEND(obj))) { |
| 84 | error_setg(&local_err, "cannot change property value"); |
| 85 | goto out; |
| 86 | } |
| 87 | |
| 88 | visit_type_size(v, name, &value, &local_err); |
| 89 | if (local_err) { |
| 90 | goto out; |
| 91 | } |
| 92 | if (!value) { |
| 93 | error_setg(&local_err, "Property '%s.%s' doesn't take value '%" |
| 94 | PRIu64 "'", object_get_typename(obj), name, value); |
| 95 | goto out; |
| 96 | } |
| 97 | m->hugetlbsize = value; |
| 98 | out: |
| 99 | error_propagate(errp, local_err); |
| 100 | } |
| 101 | |
| 102 | static void |
| 103 | memfd_backend_get_hugetlbsize(Object *obj, Visitor *v, const char *name, |
| 104 | void *opaque, Error **errp) |
| 105 | { |
| 106 | HostMemoryBackendMemfd *m = MEMORY_BACKEND_MEMFD(obj); |
| 107 | uint64_t value = m->hugetlbsize; |
| 108 | |
| 109 | visit_type_size(v, name, &value, errp); |
| 110 | } |
| 111 | |
| 112 | static bool |
| 113 | memfd_backend_get_seal(Object *o, Error **errp) |
| 114 | { |
| 115 | return MEMORY_BACKEND_MEMFD(o)->seal; |
| 116 | } |
| 117 | |
| 118 | static void |
| 119 | memfd_backend_set_seal(Object *o, bool value, Error **errp) |
| 120 | { |
| 121 | MEMORY_BACKEND_MEMFD(o)->seal = value; |
| 122 | } |
| 123 | |
| 124 | static void |
| 125 | memfd_backend_instance_init(Object *obj) |
| 126 | { |
| 127 | HostMemoryBackendMemfd *m = MEMORY_BACKEND_MEMFD(obj); |
| 128 | |
| 129 | /* default to sealed file */ |
| 130 | m->seal = true; |
Marc-André Lureau | 36ea397 | 2018-08-28 17:38:40 +0200 | [diff] [blame] | 131 | MEMORY_BACKEND(m)->share = true; |
Marc-André Lureau | dbb9e0f | 2018-02-01 14:27:54 +0100 | [diff] [blame] | 132 | } |
| 133 | |
| 134 | static void |
| 135 | memfd_backend_class_init(ObjectClass *oc, void *data) |
| 136 | { |
| 137 | HostMemoryBackendClass *bc = MEMORY_BACKEND_CLASS(oc); |
| 138 | |
| 139 | bc->alloc = memfd_backend_memory_alloc; |
| 140 | |
Marc-André Lureau | 3829640 | 2018-09-06 20:14:15 +0400 | [diff] [blame] | 141 | if (qemu_memfd_check(MFD_HUGETLB)) { |
| 142 | object_class_property_add_bool(oc, "hugetlb", |
| 143 | memfd_backend_get_hugetlb, |
| 144 | memfd_backend_set_hugetlb, |
| 145 | &error_abort); |
Marc-André Lureau | 033bfc5 | 2018-09-06 18:39:08 +0400 | [diff] [blame] | 146 | object_class_property_set_description(oc, "hugetlb", |
| 147 | "Use huge pages", |
| 148 | &error_abort); |
Marc-André Lureau | 3829640 | 2018-09-06 20:14:15 +0400 | [diff] [blame] | 149 | object_class_property_add(oc, "hugetlbsize", "int", |
| 150 | memfd_backend_get_hugetlbsize, |
| 151 | memfd_backend_set_hugetlbsize, |
| 152 | NULL, NULL, &error_abort); |
Marc-André Lureau | 033bfc5 | 2018-09-06 18:39:08 +0400 | [diff] [blame] | 153 | object_class_property_set_description(oc, "hugetlbsize", |
| 154 | "Huge pages size (ex: 2M, 1G)", |
| 155 | &error_abort); |
Marc-André Lureau | 3829640 | 2018-09-06 20:14:15 +0400 | [diff] [blame] | 156 | } |
Ilya Maximets | 4a66c7a | 2019-03-11 16:58:47 +0300 | [diff] [blame] | 157 | object_class_property_add_bool(oc, "seal", |
| 158 | memfd_backend_get_seal, |
| 159 | memfd_backend_set_seal, |
| 160 | &error_abort); |
| 161 | object_class_property_set_description(oc, "seal", |
| 162 | "Seal growing & shrinking", |
| 163 | &error_abort); |
Marc-André Lureau | dbb9e0f | 2018-02-01 14:27:54 +0100 | [diff] [blame] | 164 | } |
| 165 | |
| 166 | static const TypeInfo memfd_backend_info = { |
| 167 | .name = TYPE_MEMORY_BACKEND_MEMFD, |
| 168 | .parent = TYPE_MEMORY_BACKEND, |
| 169 | .instance_init = memfd_backend_instance_init, |
| 170 | .class_init = memfd_backend_class_init, |
| 171 | .instance_size = sizeof(HostMemoryBackendMemfd), |
| 172 | }; |
| 173 | |
| 174 | static void register_types(void) |
| 175 | { |
Ilya Maximets | 4a66c7a | 2019-03-11 16:58:47 +0300 | [diff] [blame] | 176 | if (qemu_memfd_check(MFD_ALLOW_SEALING)) { |
Marc-André Lureau | 3829640 | 2018-09-06 20:14:15 +0400 | [diff] [blame] | 177 | type_register_static(&memfd_backend_info); |
| 178 | } |
Marc-André Lureau | dbb9e0f | 2018-02-01 14:27:54 +0100 | [diff] [blame] | 179 | } |
| 180 | |
| 181 | type_init(register_types); |