vfio/mdev: simplify mdev_type handling

Instead of abusing struct attribute_group to control initialization of struct mdev_type, just define the actual attributes in the mdev_driver, allocate the mdev_type structures in the caller and pass them to mdev_register_parent. This allows the caller to use container_of to get at the containing structure and thus significantly simplify the code.

Christoph Hellwig committed 4 years ago

Commit da44c341 parent 89345d517 files · +165 −326Browse files

Showing the changes to samples (3 of 17 files). Show all

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3 files

samples/vfio-mdev/mbochs.c +23 −34
samples/vfio-mdev/mdpy.c +19 −31
samples/vfio-mdev/mtty.c +30 −30

samples/vfio-mdev/mbochs.c+23−34

@@ -99,23 +99,27 @@ MODULE_PARM_DESC(mem, "megabytes available to " MBOCHS_NAME " devices"); · 98 unmodified lines
99	99	#define MBOCHS_TYPE_2 "medium"
100	100	#define MBOCHS_TYPE_3 "large"
101	101
102		−static const struct mbochs_type {
	102	+static struct mbochs_type {
	103	+ struct mdev_type type;
103	104	const char *name;
104	105	u32 mbytes;
105	106	u32 max_x;
106	107	u32 max_y;
107	108	} mbochs_types[] = {
108	109	{
	110	+ .type.sysfs_name = MBOCHS_TYPE_1,
109	111	.name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1,
110	112	.mbytes = 4,
111	113	.max_x = 800,
112	114	.max_y = 600,
113	115	}, {
	116	+ .type.sysfs_name = MBOCHS_TYPE_2,
114	117	.name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2,
115	118	.mbytes = 16,
116	119	.max_x = 1920,
117	120	.max_y = 1440,
118	121	}, {
	122	+ .type.sysfs_name = MBOCHS_TYPE_3,
119	123	.name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3,
120	124	.mbytes = 64,
121	125	.max_x = 0,
@@ -123,6 +127,11 @@ static const struct mbochs_type { · 1 unmodified line
123	127	},
124	128	};
125	129
	130	+static struct mdev_type *mbochs_mdev_types[] = {
	131	+ &mbochs_types[0].type,
	132	+ &mbochs_types[1].type,
	133	+ &mbochs_types[2].type,
	134	+};
126	135
127	136	static dev_t mbochs_devt;
128	137	static struct class *mbochs_class;
@@ -510,8 +519,8 @@ static int mbochs_init_dev(struct vfio_device *vdev) · 381 unmodified lines
510	519	struct mdev_state *mdev_state =
511	520	container_of(vdev, struct mdev_state, vdev);
512	521	struct mdev_device *mdev = to_mdev_device(vdev->dev);
513		− const struct mbochs_type *type =
514		− &mbochs_types[mdev_get_type_group_id(mdev)];
	522	+ struct mbochs_type *type =
	523	+ container_of(mdev->type, struct mbochs_type, type);
515	524	int avail_mbytes = atomic_read(&mbochs_avail_mbytes);
516	525	int ret = -ENOMEM;
517	526
@@ -1345,8 +1354,8 @@ static const struct attribute_group *mdev_dev_groups[] = { · 827 unmodified lines
1345	1354	static ssize_t name_show(struct mdev_type *mtype,
1346	1355	struct mdev_type_attribute attr, char buf)
1347	1356	{
1348		− const struct mbochs_type *type =
1349		− &mbochs_types[mtype_get_type_group_id(mtype)];
	1357	+ struct mbochs_type *type =
	1358	+ container_of(mtype, struct mbochs_type, type);
1350	1359
1351	1360	return sprintf(buf, "%s\n", type->name);
1352	1361	}
@@ -1355,8 +1364,8 @@ static MDEV_TYPE_ATTR_RO(name); · 2 unmodified lines
1355	1364	static ssize_t description_show(struct mdev_type *mtype,
1356	1365	struct mdev_type_attribute attr, char buf)
1357	1366	{
1358		− const struct mbochs_type *type =
1359		− &mbochs_types[mtype_get_type_group_id(mtype)];
	1367	+ struct mbochs_type *type =
	1368	+ container_of(mtype, struct mbochs_type, type);
1360	1369
1361	1370	return sprintf(buf, "virtual display, %d MB video memory\n",
1362	1371	type ? type->mbytes : 0);
@@ -1367,8 +1376,8 @@ static ssize_t available_instances_show(struct mdev_type *mtype, · 4 unmodified lines
1367	1376	struct mdev_type_attribute *attr,
1368	1377	char *buf)
1369	1378	{
1370		− const struct mbochs_type *type =
1371		− &mbochs_types[mtype_get_type_group_id(mtype)];
	1379	+ struct mbochs_type *type =
	1380	+ container_of(mtype, struct mbochs_type, type);
1372	1381	int count = atomic_read(&mbochs_avail_mbytes) / type->mbytes;
1373	1382
1374	1383	return sprintf(buf, "%d\n", count);
@@ -1382,7 +1391,7 @@ static ssize_t device_api_show(struct mdev_type *mtype, · 7 unmodified lines
1382	1391	}
1383	1392	static MDEV_TYPE_ATTR_RO(device_api);
1384	1393
1385		−static struct attribute *mdev_types_attrs[] = {
	1394	+static const struct attribute *mdev_types_attrs[] = {
1386	1395	&mdev_type_attr_name.attr,
1387	1396	&mdev_type_attr_description.attr,
1388	1397	&mdev_type_attr_device_api.attr,
@@ -1390,28 +1399,6 @@ static struct attribute *mdev_types_attrs[] = { · 1 unmodified line
1390	1399	NULL,
1391	1400	};
1392	1401
1393		−static struct attribute_group mdev_type_group1 = {
1394		− .name = MBOCHS_TYPE_1,
1395		− .attrs = mdev_types_attrs,
1396		−};
1397		−
1398		−static struct attribute_group mdev_type_group2 = {
1399		− .name = MBOCHS_TYPE_2,
1400		− .attrs = mdev_types_attrs,
1401		−};
1402		−
1403		−static struct attribute_group mdev_type_group3 = {
1404		− .name = MBOCHS_TYPE_3,
1405		− .attrs = mdev_types_attrs,
1406		−};
1407		−
1408		−static struct attribute_group *mdev_type_groups[] = {
1409		− &mdev_type_group1,
1410		− &mdev_type_group2,
1411		− &mdev_type_group3,
1412		− NULL,
1413		−};
1414		−
1415	1402	static const struct vfio_device_ops mbochs_dev_ops = {
1416	1403	.close_device = mbochs_close_device,
1417	1404	.init = mbochs_init_dev,
@@ -1431,7 +1418,7 @@ static struct mdev_driver mbochs_driver = { · 13 unmodified lines
1431	1418	},
1432	1419	.probe = mbochs_probe,
1433	1420	.remove = mbochs_remove,
1434		− .supported_type_groups = mdev_type_groups,
	1421	+ .types_attrs = mdev_types_attrs,
1435	1422	};
1436	1423
1437	1424	static const struct file_operations vd_fops = {
@@ -1476,7 +1463,9 @@ static int __init mbochs_dev_init(void) · 38 unmodified lines
1476	1463	if (ret)
1477	1464	goto err_class;
1478	1465
1479		− ret = mdev_register_parent(&mbochs_parent, &mbochs_dev, &mbochs_driver);
	1466	+ ret = mdev_register_parent(&mbochs_parent, &mbochs_dev, &mbochs_driver,
	1467	+ mbochs_mdev_types,
	1468	+ ARRAY_SIZE(mbochs_mdev_types));
1480	1469	if (ret)
1481	1470	goto err_device;
1482	1471

samples/vfio-mdev/mdpy.c+19−31

@@ -51,7 +51,8 @@ MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices"); · 50 unmodified lines
51	51	#define MDPY_TYPE_2 "xga"
52	52	#define MDPY_TYPE_3 "hd"
53	53
54		−static const struct mdpy_type {
	54	+static struct mdpy_type {
	55	+ struct mdev_type type;
55	56	const char *name;
56	57	u32 format;
57	58	u32 bytepp;
@@ -59,18 +60,21 @@ static const struct mdpy_type { · 1 unmodified line
59	60	u32 height;
60	61	} mdpy_types[] = {
61	62	{
	63	+ .type.sysfs_name = MDPY_TYPE_1,
62	64	.name = MDPY_CLASS_NAME "-" MDPY_TYPE_1,
63	65	.format = DRM_FORMAT_XRGB8888,
64	66	.bytepp = 4,
65	67	.width = 640,
66	68	.height = 480,
67	69	}, {
	70	+ .type.sysfs_name = MDPY_TYPE_2,
68	71	.name = MDPY_CLASS_NAME "-" MDPY_TYPE_2,
69	72	.format = DRM_FORMAT_XRGB8888,
70	73	.bytepp = 4,
71	74	.width = 1024,
72	75	.height = 768,
73	76	}, {
	77	+ .type.sysfs_name = MDPY_TYPE_3,
74	78	.name = MDPY_CLASS_NAME "-" MDPY_TYPE_3,
75	79	.format = DRM_FORMAT_XRGB8888,
76	80	.bytepp = 4,
@@ -79,6 +83,12 @@ static const struct mdpy_type { · 2 unmodified lines
79	83	},
80	84	};
81	85
	86	+static struct mdev_type *mdpy_mdev_types[] = {
	87	+ &mdpy_types[0].type,
	88	+ &mdpy_types[1].type,
	89	+ &mdpy_types[2].type,
	90	+};
	91	+
82	92	static dev_t mdpy_devt;
83	93	static struct class *mdpy_class;
84	94	static struct cdev mdpy_cdev;
@@ -222,7 +232,7 @@ static int mdpy_init_dev(struct vfio_device *vdev) · 137 unmodified lines
222	232	container_of(vdev, struct mdev_state, vdev);
223	233	struct mdev_device *mdev = to_mdev_device(vdev->dev);
224	234	const struct mdpy_type *type =
225		− &mdpy_types[mdev_get_type_group_id(mdev)];
	235	+ container_of(mdev->type, struct mdpy_type, type);
226	236	u32 fbsize;
227	237	int ret = -ENOMEM;
228	238
@@ -655,8 +665,7 @@ static const struct attribute_group *mdev_dev_groups[] = { · 426 unmodified lines
655	665	static ssize_t name_show(struct mdev_type *mtype,
656	666	struct mdev_type_attribute attr, char buf)
657	667	{
658		− const struct mdpy_type *type =
659		− &mdpy_types[mtype_get_type_group_id(mtype)];
	668	+ struct mdpy_type *type = container_of(mtype, struct mdpy_type, type);
660	669
661	670	return sprintf(buf, "%s\n", type->name);
662	671	}
@@ -665,8 +674,7 @@ static MDEV_TYPE_ATTR_RO(name); · 2 unmodified lines
665	674	static ssize_t description_show(struct mdev_type *mtype,
666	675	struct mdev_type_attribute attr, char buf)
667	676	{
668		− const struct mdpy_type *type =
669		− &mdpy_types[mtype_get_type_group_id(mtype)];
	677	+ struct mdpy_type *type = container_of(mtype, struct mdpy_type, type);
670	678
671	679	return sprintf(buf, "virtual display, %dx%d framebuffer\n",
672	680	type->width, type->height);
@@ -688,7 +696,7 @@ static ssize_t device_api_show(struct mdev_type *mtype, · 15 unmodified lines
688	696	}
689	697	static MDEV_TYPE_ATTR_RO(device_api);
690	698
691		−static struct attribute *mdev_types_attrs[] = {
	699	+static const struct attribute *mdev_types_attrs[] = {
692	700	&mdev_type_attr_name.attr,
693	701	&mdev_type_attr_description.attr,
694	702	&mdev_type_attr_device_api.attr,
@@ -696,28 +704,6 @@ static struct attribute *mdev_types_attrs[] = { · 1 unmodified line
696	704	NULL,
697	705	};
698	706
699		−static struct attribute_group mdev_type_group1 = {
700		− .name = MDPY_TYPE_1,
701		− .attrs = mdev_types_attrs,
702		−};
703		−
704		−static struct attribute_group mdev_type_group2 = {
705		− .name = MDPY_TYPE_2,
706		− .attrs = mdev_types_attrs,
707		−};
708		−
709		−static struct attribute_group mdev_type_group3 = {
710		− .name = MDPY_TYPE_3,
711		− .attrs = mdev_types_attrs,
712		−};
713		−
714		−static struct attribute_group *mdev_type_groups[] = {
715		− &mdev_type_group1,
716		− &mdev_type_group2,
717		− &mdev_type_group3,
718		− NULL,
719		−};
720		−
721	707	static const struct vfio_device_ops mdpy_dev_ops = {
722	708	.init = mdpy_init_dev,
723	709	.release = mdpy_release_dev,
@@ -736,7 +722,7 @@ static struct mdev_driver mdpy_driver = { · 12 unmodified lines
736	722	},
737	723	.probe = mdpy_probe,
738	724	.remove = mdpy_remove,
739		− .supported_type_groups = mdev_type_groups,
	725	+ .types_attrs = mdev_types_attrs,
740	726	};
741	727
742	728	static const struct file_operations vd_fops = {
@@ -779,7 +765,9 @@ static int __init mdpy_dev_init(void) · 36 unmodified lines
779	765	if (ret)
780	766	goto err_class;
781	767
782		− ret = mdev_register_parent(&mdpy_parent, &mdpy_dev, &mdpy_driver);
	768	+ ret = mdev_register_parent(&mdpy_parent, &mdpy_dev, &mdpy_driver,
	769	+ mdpy_mdev_types,
	770	+ ARRAY_SIZE(mdpy_mdev_types));
783	771	if (ret)
784	772	goto err_device;
785	773

samples/vfio-mdev/mtty.c+30−30

@@ -143,6 +143,20 @@ struct mdev_state { · 142 unmodified lines
143	143	int nr_ports;
144	144	};
145	145
	146	+static struct mtty_type {
	147	+ struct mdev_type type;
	148	+ int nr_ports;
	149	+ const char *name;
	150	+} mtty_types[2] = {
	151	+ { .nr_ports = 1, .type.sysfs_name = "1", .name = "Single port serial" },
	152	+ { .nr_ports = 2, .type.sysfs_name = "2", .name = "Dual port serial" },
	153	+};
	154	+
	155	+static struct mdev_type *mtty_mdev_types[] = {
	156	+ &mtty_types[0].type,
	157	+ &mtty_types[1].type,
	158	+};
	159	+
146	160	static atomic_t mdev_avail_ports = ATOMIC_INIT(MAX_MTTYS);
147	161
148	162	static const struct file_operations vd_fops = {
@@ -707,17 +721,19 @@ static int mtty_init_dev(struct vfio_device *vdev) · 558 unmodified lines
707	721	struct mdev_state *mdev_state =
708	722	container_of(vdev, struct mdev_state, vdev);
709	723	struct mdev_device *mdev = to_mdev_device(vdev->dev);
710		− int nr_ports = mdev_get_type_group_id(mdev) + 1;
	724	+ struct mtty_type *type =
	725	+ container_of(mdev->type, struct mtty_type, type);
711	726	int avail_ports = atomic_read(&mdev_avail_ports);
712	727	int ret;
713	728
714	729	do {
715		− if (avail_ports < nr_ports)
	730	+ if (avail_ports < type->nr_ports)
716	731	return -ENOSPC;
717	732	} while (!atomic_try_cmpxchg(&mdev_avail_ports,
718		− &avail_ports, avail_ports - nr_ports));
	733	+ &avail_ports,
	734	+ avail_ports - type->nr_ports));
719	735
720		− mdev_state->nr_ports = nr_ports;
	736	+ mdev_state->nr_ports = type->nr_ports;
721	737	mdev_state->irq_index = -1;
722	738	mdev_state->s[0].max_fifo_size = MAX_FIFO_SIZE;
723	739	mdev_state->s[1].max_fifo_size = MAX_FIFO_SIZE;
@@ -735,7 +751,7 @@ static int mtty_init_dev(struct vfio_device *vdev) · 11 unmodified lines
735	751	return 0;
736	752
737	753	err_nr_ports:
738		− atomic_add(nr_ports, &mdev_avail_ports);
	754	+ atomic_add(type->nr_ports, &mdev_avail_ports);
739	755	return ret;
740	756	}
741	757
@@ -1242,11 +1258,9 @@ static const struct attribute_group *mdev_dev_groups[] = { · 500 unmodified lines
1242	1258	static ssize_t name_show(struct mdev_type *mtype,
1243	1259	struct mdev_type_attribute attr, char buf)
1244	1260	{
1245		− static const char *name_str[2] = { "Single port serial",
1246		− "Dual port serial" };
	1261	+ struct mtty_type *type = container_of(mtype, struct mtty_type, type);
1247	1262
1248		− return sysfs_emit(buf, "%s\n",
1249		− name_str[mtype_get_type_group_id(mtype)]);
	1263	+ return sysfs_emit(buf, "%s\n", type->name);
1250	1264	}
1251	1265
1252	1266	static MDEV_TYPE_ATTR_RO(name);
@@ -1255,9 +1269,10 @@ static ssize_t available_instances_show(struct mdev_type *mtype, · 2 unmodified lines
1255	1269	struct mdev_type_attribute *attr,
1256	1270	char *buf)
1257	1271	{
1258		− unsigned int ports = mtype_get_type_group_id(mtype) + 1;
	1272	+ struct mtty_type *type = container_of(mtype, struct mtty_type, type);
1259	1273
1260		− return sprintf(buf, "%d\n", atomic_read(&mdev_avail_ports) / ports);
	1274	+ return sprintf(buf, "%d\n", atomic_read(&mdev_avail_ports) /
	1275	+ type->nr_ports);
1261	1276	}
1262	1277
1263	1278	static MDEV_TYPE_ATTR_RO(available_instances);
@@ -1270,29 +1285,13 @@ static ssize_t device_api_show(struct mdev_type *mtype, · 6 unmodified lines
1270	1285
1271	1286	static MDEV_TYPE_ATTR_RO(device_api);
1272	1287
1273		−static struct attribute *mdev_types_attrs[] = {
	1288	+static const struct attribute *mdev_types_attrs[] = {
1274	1289	&mdev_type_attr_name.attr,
1275	1290	&mdev_type_attr_device_api.attr,
1276	1291	&mdev_type_attr_available_instances.attr,
1277	1292	NULL,
1278	1293	};
1279	1294
1280		−static struct attribute_group mdev_type_group1 = {
1281		− .name = "1",
1282		− .attrs = mdev_types_attrs,
1283		−};
1284		−
1285		−static struct attribute_group mdev_type_group2 = {
1286		− .name = "2",
1287		− .attrs = mdev_types_attrs,
1288		−};
1289		−
1290		−static struct attribute_group *mdev_type_groups[] = {
1291		− &mdev_type_group1,
1292		− &mdev_type_group2,
1293		− NULL,
1294		−};
1295		−
1296	1295	static const struct vfio_device_ops mtty_dev_ops = {
1297	1296	.name = "vfio-mtty",
1298	1297	.init = mtty_init_dev,
@@ -1311,7 +1310,7 @@ static struct mdev_driver mtty_driver = { · 12 unmodified lines
1311	1310	},
1312	1311	.probe = mtty_probe,
1313	1312	.remove = mtty_remove,
1314		− .supported_type_groups = mdev_type_groups,
	1313	+ .types_attrs = mdev_types_attrs,
1315	1314	};
1316	1315
1317	1316	static void mtty_device_release(struct device *dev)
@@ -1363,7 +1362,8 @@ static int __init mtty_dev_init(void) · 45 unmodified lines
1363	1362	goto err_class;
1364	1363
1365	1364	ret = mdev_register_parent(&mtty_dev.parent, &mtty_dev.dev,
1366		− &mtty_driver);
	1365	+ &mtty_driver, mtty_mdev_types,
	1366	+ ARRAY_SIZE(mtty_mdev_types));
1367	1367	if (ret)
1368	1368	goto err_device;
1369	1369	return 0;