module: Move sysfs support into a separate file

No functional change. This patch migrates module sysfs support out of core code into kernel/module/sysfs.c. In addition simple code refactoring to make this possible.

Aaron Tomlin committed 4 years ago

Commit 44c09531 parent 0ffc40f4 files · +461 −466Browse files

Showing the changes to kernel/module (4 of 4 files). Show all

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4 files

kernel/module/Makefile +1 −0
kernel/module/internal.h +21 −0
kernel/module/main.c +3 −466
kernel/module/sysfs.c +436 −0

kernel/module/Makefile+1−0

@@ -16,3 +16,4 @@ obj-$(CONFIG_STRICT_MODULE_RWX) += strict_rwx.o · 15 unmodified lines
16	16	obj-$(CONFIG_DEBUG_KMEMLEAK) += debug_kmemleak.o
17	17	obj-$(CONFIG_KALLSYMS) += kallsyms.o
18	18	obj-$(CONFIG_PROC_FS) += procfs.o
	19	+obj-$(CONFIG_SYSFS) += sysfs.o

kernel/module/internal.h+21−0

@@ -34,6 +34,9 @@ · 33 unmodified lines
34	34	extern struct mutex module_mutex;
35	35	extern struct list_head modules;
36	36
	37	+extern struct module_attribute *modinfo_attrs[];
	38	+extern size_t modinfo_attrs_count;
	39	+
37	40	/* Provided by the linker */
38	41	extern const struct kernel_symbol __start___ksymtab[];
39	42	extern const struct kernel_symbol __stop___ksymtab[];
@@ -204,3 +207,21 @@ static inline void init_build_id(struct module mod, const struct load_info inf · 164 unmodified lines
204	207	static inline void layout_symtab(struct module mod, struct load_info info) { }
205	208	static inline void add_kallsyms(struct module mod, const struct load_info info) { }
206	209	#endif /* CONFIG_KALLSYMS */
	210	+
	211	+#ifdef CONFIG_SYSFS
	212	+int mod_sysfs_setup(struct module mod, const struct load_info info,
	213	+ struct kernel_param *kparam, unsigned int num_params);
	214	+void mod_sysfs_teardown(struct module *mod);
	215	+void init_param_lock(struct module *mod);
	216	+#else /* !CONFIG_SYSFS */
	217	+static inline int mod_sysfs_setup(struct module *mod,
	218	+ const struct load_info *info,
	219	+ struct kernel_param *kparam,
	220	+ unsigned int num_params)
	221	+{
	222	+ return 0;
	223	+}
	224	+
	225	+static inline void mod_sysfs_teardown(struct module *mod) { }
	226	+static inline void init_param_lock(struct module *mod) { }
	227	+#endif /* CONFIG_SYSFS */

kernel/module/main.c+3−466

@@ -14,9 +14,7 @@ · 13 unmodified lines
14	14	#include <linux/init.h>
15	15	#include <linux/kallsyms.h>
16	16	#include <linux/buildid.h>
17		−#include <linux/file.h>
18	17	#include <linux/fs.h>
19		−#include <linux/sysfs.h>
20	18	#include <linux/kernel.h>
21	19	#include <linux/kernel_read_file.h>
22	20	#include <linux/slab.h>
@@ -989,7 +987,7 @@ static ssize_t show_taint(struct module_attribute *mattr, · 966 unmodified lines
989	987	static struct module_attribute modinfo_taint =
990	988	__ATTR(taint, 0444, show_taint, NULL);
991	989
992		−static struct module_attribute *modinfo_attrs[] = {
	990	+struct module_attribute *modinfo_attrs[] = {
993	991	&module_uevent,
994	992	&modinfo_version,
995	993	&modinfo_srcversion,
@@ -1003,6 +1001,8 @@ static struct module_attribute *modinfo_attrs[] = { · 7 unmodified lines
1003	1001	NULL,
1004	1002	};
1005	1003
	1004	+size_t modinfo_attrs_count = ARRAY_SIZE(modinfo_attrs);
	1005	+
1006	1006	static const char vermagic[] = VERMAGIC_STRING;
1007	1007
1008	1008	static int try_to_force_load(struct module mod, const char reason)
@@ -1253,469 +1253,6 @@ resolve_symbol_wait(struct module *mod, · 244 unmodified lines
1253	1253	return ksym;
1254	1254	}
1255	1255
1256		−/*
1257		− * /sys/module/foo/sections stuff
1258		− * J. Corbet <corbet@lwn.net>
1259		− */
1260		−#ifdef CONFIG_SYSFS
1261		−
1262		−#ifdef CONFIG_KALLSYMS
1263		−struct module_sect_attr {
1264		− struct bin_attribute battr;
1265		− unsigned long address;
1266		−};
1267		−
1268		−struct module_sect_attrs {
1269		− struct attribute_group grp;
1270		− unsigned int nsections;
1271		− struct module_sect_attr attrs[];
1272		−};
1273		−
1274		−#define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4))
1275		−static ssize_t module_sect_read(struct file file, struct kobject kobj,
1276		− struct bin_attribute *battr,
1277		− char *buf, loff_t pos, size_t count)
1278		−{
1279		− struct module_sect_attr *sattr =
1280		− container_of(battr, struct module_sect_attr, battr);
1281		− char bounce[MODULE_SECT_READ_SIZE + 1];
1282		− size_t wrote;
1283		−
1284		− if (pos != 0)
1285		− return -EINVAL;
1286		−
1287		− /*
1288		− * Since we're a binary read handler, we must account for the
1289		− * trailing NUL byte that sprintf will write: if "buf" is
1290		− * too small to hold the NUL, or the NUL is exactly the last
1291		− * byte, the read will look like it got truncated by one byte.
1292		− * Since there is no way to ask sprintf nicely to not write
1293		− * the NUL, we have to use a bounce buffer.
1294		− */
1295		− wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n",
1296		− kallsyms_show_value(file->f_cred)
1297		− ? (void *)sattr->address : NULL);
1298		− count = min(count, wrote);
1299		− memcpy(buf, bounce, count);
1300		−
1301		− return count;
1302		−}
1303		−
1304		−static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1305		−{
1306		− unsigned int section;
1307		−
1308		− for (section = 0; section < sect_attrs->nsections; section++)
1309		− kfree(sect_attrs->attrs[section].battr.attr.name);
1310		− kfree(sect_attrs);
1311		−}
1312		−
1313		−static void add_sect_attrs(struct module mod, const struct load_info info)
1314		−{
1315		− unsigned int nloaded = 0, i, size[2];
1316		− struct module_sect_attrs *sect_attrs;
1317		− struct module_sect_attr *sattr;
1318		− struct bin_attribute **gattr;
1319		−
1320		− /* Count loaded sections and allocate structures */
1321		− for (i = 0; i < info->hdr->e_shnum; i++)
1322		− if (!sect_empty(&info->sechdrs[i]))
1323		− nloaded++;
1324		− size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded),
1325		− sizeof(sect_attrs->grp.bin_attrs[0]));
1326		− size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.bin_attrs[0]);
1327		− sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1328		− if (sect_attrs == NULL)
1329		− return;
1330		−
1331		− /* Setup section attributes. */
1332		− sect_attrs->grp.name = "sections";
1333		− sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0];
1334		−
1335		− sect_attrs->nsections = 0;
1336		− sattr = &sect_attrs->attrs[0];
1337		− gattr = &sect_attrs->grp.bin_attrs[0];
1338		− for (i = 0; i < info->hdr->e_shnum; i++) {
1339		− Elf_Shdr *sec = &info->sechdrs[i];
1340		− if (sect_empty(sec))
1341		− continue;
1342		− sysfs_bin_attr_init(&sattr->battr);
1343		− sattr->address = sec->sh_addr;
1344		− sattr->battr.attr.name =
1345		− kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL);
1346		− if (sattr->battr.attr.name == NULL)
1347		− goto out;
1348		− sect_attrs->nsections++;
1349		− sattr->battr.read = module_sect_read;
1350		− sattr->battr.size = MODULE_SECT_READ_SIZE;
1351		− sattr->battr.attr.mode = 0400;
1352		− *(gattr++) = &(sattr++)->battr;
1353		− }
1354		− *gattr = NULL;
1355		−
1356		− if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1357		− goto out;
1358		−
1359		− mod->sect_attrs = sect_attrs;
1360		− return;
1361		− out:
1362		− free_sect_attrs(sect_attrs);
1363		−}
1364		−
1365		−static void remove_sect_attrs(struct module *mod)
1366		−{
1367		− if (mod->sect_attrs) {
1368		− sysfs_remove_group(&mod->mkobj.kobj,
1369		− &mod->sect_attrs->grp);
1370		− /*
1371		− * We are positive that no one is using any sect attrs
1372		− * at this point. Deallocate immediately.
1373		− */
1374		− free_sect_attrs(mod->sect_attrs);
1375		− mod->sect_attrs = NULL;
1376		− }
1377		−}
1378		−
1379		−/*
1380		− * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1381		− */
1382		−
1383		−struct module_notes_attrs {
1384		− struct kobject *dir;
1385		− unsigned int notes;
1386		− struct bin_attribute attrs[];
1387		−};
1388		−
1389		−static ssize_t module_notes_read(struct file filp, struct kobject kobj,
1390		− struct bin_attribute *bin_attr,
1391		− char *buf, loff_t pos, size_t count)
1392		−{
1393		− /*
1394		− * The caller checked the pos and count against our size.
1395		− */
1396		− memcpy(buf, bin_attr->private + pos, count);
1397		− return count;
1398		−}
1399		−
1400		−static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1401		− unsigned int i)
1402		−{
1403		− if (notes_attrs->dir) {
1404		− while (i-- > 0)
1405		− sysfs_remove_bin_file(notes_attrs->dir,
1406		− &notes_attrs->attrs[i]);
1407		− kobject_put(notes_attrs->dir);
1408		− }
1409		− kfree(notes_attrs);
1410		−}
1411		−
1412		−static void add_notes_attrs(struct module mod, const struct load_info info)
1413		−{
1414		− unsigned int notes, loaded, i;
1415		− struct module_notes_attrs *notes_attrs;
1416		− struct bin_attribute *nattr;
1417		−
1418		− /* failed to create section attributes, so can't create notes */
1419		− if (!mod->sect_attrs)
1420		− return;
1421		−
1422		− /* Count notes sections and allocate structures. */
1423		− notes = 0;
1424		− for (i = 0; i < info->hdr->e_shnum; i++)
1425		− if (!sect_empty(&info->sechdrs[i]) &&
1426		− (info->sechdrs[i].sh_type == SHT_NOTE))
1427		− ++notes;
1428		−
1429		− if (notes == 0)
1430		− return;
1431		−
1432		− notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes),
1433		− GFP_KERNEL);
1434		− if (notes_attrs == NULL)
1435		− return;
1436		−
1437		− notes_attrs->notes = notes;
1438		− nattr = &notes_attrs->attrs[0];
1439		− for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1440		− if (sect_empty(&info->sechdrs[i]))
1441		− continue;
1442		− if (info->sechdrs[i].sh_type == SHT_NOTE) {
1443		− sysfs_bin_attr_init(nattr);
1444		− nattr->attr.name = mod->sect_attrs->attrs[loaded].battr.attr.name;
1445		− nattr->attr.mode = S_IRUGO;
1446		− nattr->size = info->sechdrs[i].sh_size;
1447		− nattr->private = (void *) info->sechdrs[i].sh_addr;
1448		− nattr->read = module_notes_read;
1449		− ++nattr;
1450		− }
1451		− ++loaded;
1452		− }
1453		−
1454		− notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1455		− if (!notes_attrs->dir)
1456		− goto out;
1457		−
1458		− for (i = 0; i < notes; ++i)
1459		− if (sysfs_create_bin_file(notes_attrs->dir,
1460		− &notes_attrs->attrs[i]))
1461		− goto out;
1462		−
1463		− mod->notes_attrs = notes_attrs;
1464		− return;
1465		−
1466		− out:
1467		− free_notes_attrs(notes_attrs, i);
1468		−}
1469		−
1470		−static void remove_notes_attrs(struct module *mod)
1471		−{
1472		− if (mod->notes_attrs)
1473		− free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1474		−}
1475		−
1476		−#else
1477		−
1478		−static inline void add_sect_attrs(struct module *mod,
1479		− const struct load_info *info)
1480		−{
1481		−}
1482		−
1483		−static inline void remove_sect_attrs(struct module *mod)
1484		−{
1485		−}
1486		−
1487		−static inline void add_notes_attrs(struct module *mod,
1488		− const struct load_info *info)
1489		−{
1490		−}
1491		−
1492		−static inline void remove_notes_attrs(struct module *mod)
1493		−{
1494		−}
1495		−#endif /* CONFIG_KALLSYMS */
1496		−
1497		−static void del_usage_links(struct module *mod)
1498		−{
1499		−#ifdef CONFIG_MODULE_UNLOAD
1500		− struct module_use *use;
1501		−
1502		− mutex_lock(&module_mutex);
1503		− list_for_each_entry(use, &mod->target_list, target_list)
1504		− sysfs_remove_link(use->target->holders_dir, mod->name);
1505		− mutex_unlock(&module_mutex);
1506		−#endif
1507		−}
1508		−
1509		−static int add_usage_links(struct module *mod)
1510		−{
1511		− int ret = 0;
1512		−#ifdef CONFIG_MODULE_UNLOAD
1513		− struct module_use *use;
1514		−
1515		− mutex_lock(&module_mutex);
1516		− list_for_each_entry(use, &mod->target_list, target_list) {
1517		− ret = sysfs_create_link(use->target->holders_dir,
1518		− &mod->mkobj.kobj, mod->name);
1519		− if (ret)
1520		− break;
1521		− }
1522		− mutex_unlock(&module_mutex);
1523		− if (ret)
1524		− del_usage_links(mod);
1525		−#endif
1526		− return ret;
1527		−}
1528		−
1529		−static void module_remove_modinfo_attrs(struct module *mod, int end);
1530		−
1531		−static int module_add_modinfo_attrs(struct module *mod)
1532		−{
1533		− struct module_attribute *attr;
1534		− struct module_attribute *temp_attr;
1535		− int error = 0;
1536		− int i;
1537		−
1538		− mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1539		− (ARRAY_SIZE(modinfo_attrs) + 1)),
1540		− GFP_KERNEL);
1541		− if (!mod->modinfo_attrs)
1542		− return -ENOMEM;
1543		−
1544		− temp_attr = mod->modinfo_attrs;
1545		− for (i = 0; (attr = modinfo_attrs[i]); i++) {
1546		− if (!attr->test \|\| attr->test(mod)) {
1547		− memcpy(temp_attr, attr, sizeof(*temp_attr));
1548		− sysfs_attr_init(&temp_attr->attr);
1549		− error = sysfs_create_file(&mod->mkobj.kobj,
1550		− &temp_attr->attr);
1551		− if (error)
1552		− goto error_out;
1553		− ++temp_attr;
1554		− }
1555		− }
1556		−
1557		− return 0;
1558		−
1559		−error_out:
1560		− if (i > 0)
1561		− module_remove_modinfo_attrs(mod, --i);
1562		− else
1563		− kfree(mod->modinfo_attrs);
1564		− return error;
1565		−}
1566		−
1567		−static void module_remove_modinfo_attrs(struct module *mod, int end)
1568		−{
1569		− struct module_attribute *attr;
1570		− int i;
1571		−
1572		− for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1573		− if (end >= 0 && i > end)
1574		− break;
1575		− /* pick a field to test for end of list */
1576		− if (!attr->attr.name)
1577		− break;
1578		− sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
1579		− if (attr->free)
1580		− attr->free(mod);
1581		− }
1582		− kfree(mod->modinfo_attrs);
1583		−}
1584		−
1585		−static void mod_kobject_put(struct module *mod)
1586		−{
1587		− DECLARE_COMPLETION_ONSTACK(c);
1588		− mod->mkobj.kobj_completion = &c;
1589		− kobject_put(&mod->mkobj.kobj);
1590		− wait_for_completion(&c);
1591		−}
1592		−
1593		−static int mod_sysfs_init(struct module *mod)
1594		−{
1595		− int err;
1596		− struct kobject *kobj;
1597		−
1598		− if (!module_sysfs_initialized) {
1599		− pr_err("%s: module sysfs not initialized\n", mod->name);
1600		− err = -EINVAL;
1601		− goto out;
1602		− }
1603		−
1604		− kobj = kset_find_obj(module_kset, mod->name);
1605		− if (kobj) {
1606		− pr_err("%s: module is already loaded\n", mod->name);
1607		− kobject_put(kobj);
1608		− err = -EINVAL;
1609		− goto out;
1610		− }
1611		−
1612		− mod->mkobj.mod = mod;
1613		−
1614		− memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1615		− mod->mkobj.kobj.kset = module_kset;
1616		− err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1617		− "%s", mod->name);
1618		− if (err)
1619		− mod_kobject_put(mod);
1620		−
1621		−out:
1622		− return err;
1623		−}
1624		−
1625		−static int mod_sysfs_setup(struct module *mod,
1626		− const struct load_info *info,
1627		− struct kernel_param *kparam,
1628		− unsigned int num_params)
1629		−{
1630		− int err;
1631		−
1632		− err = mod_sysfs_init(mod);
1633		− if (err)
1634		− goto out;
1635		−
1636		− mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1637		− if (!mod->holders_dir) {
1638		− err = -ENOMEM;
1639		− goto out_unreg;
1640		− }
1641		−
1642		− err = module_param_sysfs_setup(mod, kparam, num_params);
1643		− if (err)
1644		− goto out_unreg_holders;
1645		−
1646		− err = module_add_modinfo_attrs(mod);
1647		− if (err)
1648		− goto out_unreg_param;
1649		−
1650		− err = add_usage_links(mod);
1651		− if (err)
1652		− goto out_unreg_modinfo_attrs;
1653		−
1654		− add_sect_attrs(mod, info);
1655		− add_notes_attrs(mod, info);
1656		−
1657		− return 0;
1658		−
1659		−out_unreg_modinfo_attrs:
1660		− module_remove_modinfo_attrs(mod, -1);
1661		−out_unreg_param:
1662		− module_param_sysfs_remove(mod);
1663		−out_unreg_holders:
1664		− kobject_put(mod->holders_dir);
1665		−out_unreg:
1666		− mod_kobject_put(mod);
1667		−out:
1668		− return err;
1669		−}
1670		−
1671		−static void mod_sysfs_fini(struct module *mod)
1672		−{
1673		− remove_notes_attrs(mod);
1674		− remove_sect_attrs(mod);
1675		− mod_kobject_put(mod);
1676		−}
1677		−
1678		−static void init_param_lock(struct module *mod)
1679		−{
1680		− mutex_init(&mod->param_lock);
1681		−}
1682		−#else /* !CONFIG_SYSFS */
1683		−
1684		−static int mod_sysfs_setup(struct module *mod,
1685		− const struct load_info *info,
1686		− struct kernel_param *kparam,
1687		− unsigned int num_params)
1688		−{
1689		− return 0;
1690		−}
1691		−
1692		−static void mod_sysfs_fini(struct module *mod)
1693		−{
1694		−}
1695		−
1696		−static void module_remove_modinfo_attrs(struct module *mod, int end)
1697		−{
1698		−}
1699		−
1700		−static void del_usage_links(struct module *mod)
1701		−{
1702		−}
1703		−
1704		−static void init_param_lock(struct module *mod)
1705		−{
1706		−}
1707		−#endif /* CONFIG_SYSFS */
1708		−
1709		−static void mod_sysfs_teardown(struct module *mod)
1710		−{
1711		− del_usage_links(mod);
1712		− module_remove_modinfo_attrs(mod, -1);
1713		− module_param_sysfs_remove(mod);
1714		− kobject_put(mod->mkobj.drivers_dir);
1715		− kobject_put(mod->holders_dir);
1716		− mod_sysfs_fini(mod);
1717		−}
1718		−
1719	1256	/*
1720	1257	* LKM RO/NX protection: protect module's text/ro-data
1721	1258	* from modification and any data from execution.

kernel/module/sysfs.c+436−0

@@ -0,0 +1,436 @@
	1	+// SPDX-License-Identifier: GPL-2.0-or-later
	2	+/*
	3	+ * Module sysfs support
	4	+ *
	5	+ * Copyright (C) 2008 Rusty Russell
	6	+ */
	7	+
	8	+#include <linux/module.h>
	9	+#include <linux/kernel.h>
	10	+#include <linux/fs.h>
	11	+#include <linux/sysfs.h>
	12	+#include <linux/slab.h>
	13	+#include <linux/kallsyms.h>
	14	+#include <linux/mutex.h>
	15	+#include "internal.h"
	16	+
	17	+/*
	18	+ * /sys/module/foo/sections stuff
	19	+ * J. Corbet <corbet@lwn.net>
	20	+ */
	21	+#ifdef CONFIG_KALLSYMS
	22	+struct module_sect_attr {
	23	+ struct bin_attribute battr;
	24	+ unsigned long address;
	25	+};
	26	+
	27	+struct module_sect_attrs {
	28	+ struct attribute_group grp;
	29	+ unsigned int nsections;
	30	+ struct module_sect_attr attrs[];
	31	+};
	32	+
	33	+#define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4))
	34	+static ssize_t module_sect_read(struct file file, struct kobject kobj,
	35	+ struct bin_attribute *battr,
	36	+ char *buf, loff_t pos, size_t count)
	37	+{
	38	+ struct module_sect_attr *sattr =
	39	+ container_of(battr, struct module_sect_attr, battr);
	40	+ char bounce[MODULE_SECT_READ_SIZE + 1];
	41	+ size_t wrote;
	42	+
	43	+ if (pos != 0)
	44	+ return -EINVAL;
	45	+
	46	+ /*
	47	+ * Since we're a binary read handler, we must account for the
	48	+ * trailing NUL byte that sprintf will write: if "buf" is
	49	+ * too small to hold the NUL, or the NUL is exactly the last
	50	+ * byte, the read will look like it got truncated by one byte.
	51	+ * Since there is no way to ask sprintf nicely to not write
	52	+ * the NUL, we have to use a bounce buffer.
	53	+ */
	54	+ wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n",
	55	+ kallsyms_show_value(file->f_cred)
	56	+ ? (void *)sattr->address : NULL);
	57	+ count = min(count, wrote);
	58	+ memcpy(buf, bounce, count);
	59	+
	60	+ return count;
	61	+}
	62	+
	63	+static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
	64	+{
	65	+ unsigned int section;
	66	+
	67	+ for (section = 0; section < sect_attrs->nsections; section++)
	68	+ kfree(sect_attrs->attrs[section].battr.attr.name);
	69	+ kfree(sect_attrs);
	70	+}
	71	+
	72	+static void add_sect_attrs(struct module mod, const struct load_info info)
	73	+{
	74	+ unsigned int nloaded = 0, i, size[2];
	75	+ struct module_sect_attrs *sect_attrs;
	76	+ struct module_sect_attr *sattr;
	77	+ struct bin_attribute **gattr;
	78	+
	79	+ /* Count loaded sections and allocate structures */
	80	+ for (i = 0; i < info->hdr->e_shnum; i++)
	81	+ if (!sect_empty(&info->sechdrs[i]))
	82	+ nloaded++;
	83	+ size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded),
	84	+ sizeof(sect_attrs->grp.bin_attrs[0]));
	85	+ size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.bin_attrs[0]);
	86	+ sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
	87	+ if (!sect_attrs)
	88	+ return;
	89	+
	90	+ /* Setup section attributes. */
	91	+ sect_attrs->grp.name = "sections";
	92	+ sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0];
	93	+
	94	+ sect_attrs->nsections = 0;
	95	+ sattr = &sect_attrs->attrs[0];
	96	+ gattr = &sect_attrs->grp.bin_attrs[0];
	97	+ for (i = 0; i < info->hdr->e_shnum; i++) {
	98	+ Elf_Shdr *sec = &info->sechdrs[i];
	99	+
	100	+ if (sect_empty(sec))
	101	+ continue;
	102	+ sysfs_bin_attr_init(&sattr->battr);
	103	+ sattr->address = sec->sh_addr;
	104	+ sattr->battr.attr.name =
	105	+ kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL);
	106	+ if (!sattr->battr.attr.name)
	107	+ goto out;
	108	+ sect_attrs->nsections++;
	109	+ sattr->battr.read = module_sect_read;
	110	+ sattr->battr.size = MODULE_SECT_READ_SIZE;
	111	+ sattr->battr.attr.mode = 0400;
	112	+ *(gattr++) = &(sattr++)->battr;
	113	+ }
	114	+ *gattr = NULL;
	115	+
	116	+ if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
	117	+ goto out;
	118	+
	119	+ mod->sect_attrs = sect_attrs;
	120	+ return;
	121	+out:
	122	+ free_sect_attrs(sect_attrs);
	123	+}
	124	+
	125	+static void remove_sect_attrs(struct module *mod)
	126	+{
	127	+ if (mod->sect_attrs) {
	128	+ sysfs_remove_group(&mod->mkobj.kobj,
	129	+ &mod->sect_attrs->grp);
	130	+ /*
	131	+ * We are positive that no one is using any sect attrs
	132	+ * at this point. Deallocate immediately.
	133	+ */
	134	+ free_sect_attrs(mod->sect_attrs);
	135	+ mod->sect_attrs = NULL;
	136	+ }
	137	+}
	138	+
	139	+/*
	140	+ * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
	141	+ */
	142	+
	143	+struct module_notes_attrs {
	144	+ struct kobject *dir;
	145	+ unsigned int notes;
	146	+ struct bin_attribute attrs[];
	147	+};
	148	+
	149	+static ssize_t module_notes_read(struct file filp, struct kobject kobj,
	150	+ struct bin_attribute *bin_attr,
	151	+ char *buf, loff_t pos, size_t count)
	152	+{
	153	+ /*
	154	+ * The caller checked the pos and count against our size.
	155	+ */
	156	+ memcpy(buf, bin_attr->private + pos, count);
	157	+ return count;
	158	+}
	159	+
	160	+static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
	161	+ unsigned int i)
	162	+{
	163	+ if (notes_attrs->dir) {
	164	+ while (i-- > 0)
	165	+ sysfs_remove_bin_file(notes_attrs->dir,
	166	+ &notes_attrs->attrs[i]);
	167	+ kobject_put(notes_attrs->dir);
	168	+ }
	169	+ kfree(notes_attrs);
	170	+}
	171	+
	172	+static void add_notes_attrs(struct module mod, const struct load_info info)
	173	+{
	174	+ unsigned int notes, loaded, i;
	175	+ struct module_notes_attrs *notes_attrs;
	176	+ struct bin_attribute *nattr;
	177	+
	178	+ /* failed to create section attributes, so can't create notes */
	179	+ if (!mod->sect_attrs)
	180	+ return;
	181	+
	182	+ /* Count notes sections and allocate structures. */
	183	+ notes = 0;
	184	+ for (i = 0; i < info->hdr->e_shnum; i++)
	185	+ if (!sect_empty(&info->sechdrs[i]) &&
	186	+ info->sechdrs[i].sh_type == SHT_NOTE)
	187	+ ++notes;
	188	+
	189	+ if (notes == 0)
	190	+ return;
	191	+
	192	+ notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes),
	193	+ GFP_KERNEL);
	194	+ if (!notes_attrs)
	195	+ return;
	196	+
	197	+ notes_attrs->notes = notes;
	198	+ nattr = &notes_attrs->attrs[0];
	199	+ for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
	200	+ if (sect_empty(&info->sechdrs[i]))
	201	+ continue;
	202	+ if (info->sechdrs[i].sh_type == SHT_NOTE) {
	203	+ sysfs_bin_attr_init(nattr);
	204	+ nattr->attr.name = mod->sect_attrs->attrs[loaded].battr.attr.name;
	205	+ nattr->attr.mode = 0444;
	206	+ nattr->size = info->sechdrs[i].sh_size;
	207	+ nattr->private = (void *)info->sechdrs[i].sh_addr;
	208	+ nattr->read = module_notes_read;
	209	+ ++nattr;
	210	+ }
	211	+ ++loaded;
	212	+ }
	213	+
	214	+ notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
	215	+ if (!notes_attrs->dir)
	216	+ goto out;
	217	+
	218	+ for (i = 0; i < notes; ++i)
	219	+ if (sysfs_create_bin_file(notes_attrs->dir,
	220	+ &notes_attrs->attrs[i]))
	221	+ goto out;
	222	+
	223	+ mod->notes_attrs = notes_attrs;
	224	+ return;
	225	+
	226	+out:
	227	+ free_notes_attrs(notes_attrs, i);
	228	+}
	229	+
	230	+static void remove_notes_attrs(struct module *mod)
	231	+{
	232	+ if (mod->notes_attrs)
	233	+ free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
	234	+}
	235	+
	236	+#else /* !CONFIG_KALLSYMS */
	237	+static inline void add_sect_attrs(struct module mod, const struct load_info info) { }
	238	+static inline void remove_sect_attrs(struct module *mod) { }
	239	+static inline void add_notes_attrs(struct module mod, const struct load_info info) { }
	240	+static inline void remove_notes_attrs(struct module *mod) { }
	241	+#endif /* CONFIG_KALLSYMS */
	242	+
	243	+static void del_usage_links(struct module *mod)
	244	+{
	245	+#ifdef CONFIG_MODULE_UNLOAD
	246	+ struct module_use *use;
	247	+
	248	+ mutex_lock(&module_mutex);
	249	+ list_for_each_entry(use, &mod->target_list, target_list)
	250	+ sysfs_remove_link(use->target->holders_dir, mod->name);
	251	+ mutex_unlock(&module_mutex);
	252	+#endif
	253	+}
	254	+
	255	+static int add_usage_links(struct module *mod)
	256	+{
	257	+ int ret = 0;
	258	+#ifdef CONFIG_MODULE_UNLOAD
	259	+ struct module_use *use;
	260	+
	261	+ mutex_lock(&module_mutex);
	262	+ list_for_each_entry(use, &mod->target_list, target_list) {
	263	+ ret = sysfs_create_link(use->target->holders_dir,
	264	+ &mod->mkobj.kobj, mod->name);
	265	+ if (ret)
	266	+ break;
	267	+ }
	268	+ mutex_unlock(&module_mutex);
	269	+ if (ret)
	270	+ del_usage_links(mod);
	271	+#endif
	272	+ return ret;
	273	+}
	274	+
	275	+static void module_remove_modinfo_attrs(struct module *mod, int end)
	276	+{
	277	+ struct module_attribute *attr;
	278	+ int i;
	279	+
	280	+ for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
	281	+ if (end >= 0 && i > end)
	282	+ break;
	283	+ /* pick a field to test for end of list */
	284	+ if (!attr->attr.name)
	285	+ break;
	286	+ sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
	287	+ if (attr->free)
	288	+ attr->free(mod);
	289	+ }
	290	+ kfree(mod->modinfo_attrs);
	291	+}
	292	+
	293	+static int module_add_modinfo_attrs(struct module *mod)
	294	+{
	295	+ struct module_attribute *attr;
	296	+ struct module_attribute *temp_attr;
	297	+ int error = 0;
	298	+ int i;
	299	+
	300	+ mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
	301	+ (modinfo_attrs_count + 1)),
	302	+ GFP_KERNEL);
	303	+ if (!mod->modinfo_attrs)
	304	+ return -ENOMEM;
	305	+
	306	+ temp_attr = mod->modinfo_attrs;
	307	+ for (i = 0; (attr = modinfo_attrs[i]); i++) {
	308	+ if (!attr->test \|\| attr->test(mod)) {
	309	+ memcpy(temp_attr, attr, sizeof(*temp_attr));
	310	+ sysfs_attr_init(&temp_attr->attr);
	311	+ error = sysfs_create_file(&mod->mkobj.kobj,
	312	+ &temp_attr->attr);
	313	+ if (error)
	314	+ goto error_out;
	315	+ ++temp_attr;
	316	+ }
	317	+ }
	318	+
	319	+ return 0;
	320	+
	321	+error_out:
	322	+ if (i > 0)
	323	+ module_remove_modinfo_attrs(mod, --i);
	324	+ else
	325	+ kfree(mod->modinfo_attrs);
	326	+ return error;
	327	+}
	328	+
	329	+static void mod_kobject_put(struct module *mod)
	330	+{
	331	+ DECLARE_COMPLETION_ONSTACK(c);
	332	+
	333	+ mod->mkobj.kobj_completion = &c;
	334	+ kobject_put(&mod->mkobj.kobj);
	335	+ wait_for_completion(&c);
	336	+}
	337	+
	338	+static int mod_sysfs_init(struct module *mod)
	339	+{
	340	+ int err;
	341	+ struct kobject *kobj;
	342	+
	343	+ if (!module_sysfs_initialized) {
	344	+ pr_err("%s: module sysfs not initialized\n", mod->name);
	345	+ err = -EINVAL;
	346	+ goto out;
	347	+ }
	348	+
	349	+ kobj = kset_find_obj(module_kset, mod->name);
	350	+ if (kobj) {
	351	+ pr_err("%s: module is already loaded\n", mod->name);
	352	+ kobject_put(kobj);
	353	+ err = -EINVAL;
	354	+ goto out;
	355	+ }
	356	+
	357	+ mod->mkobj.mod = mod;
	358	+
	359	+ memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
	360	+ mod->mkobj.kobj.kset = module_kset;
	361	+ err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
	362	+ "%s", mod->name);
	363	+ if (err)
	364	+ mod_kobject_put(mod);
	365	+
	366	+out:
	367	+ return err;
	368	+}
	369	+
	370	+int mod_sysfs_setup(struct module *mod,
	371	+ const struct load_info *info,
	372	+ struct kernel_param *kparam,
	373	+ unsigned int num_params)
	374	+{
	375	+ int err;
	376	+
	377	+ err = mod_sysfs_init(mod);
	378	+ if (err)
	379	+ goto out;
	380	+
	381	+ mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
	382	+ if (!mod->holders_dir) {
	383	+ err = -ENOMEM;
	384	+ goto out_unreg;
	385	+ }
	386	+
	387	+ err = module_param_sysfs_setup(mod, kparam, num_params);
	388	+ if (err)
	389	+ goto out_unreg_holders;
	390	+
	391	+ err = module_add_modinfo_attrs(mod);
	392	+ if (err)
	393	+ goto out_unreg_param;
	394	+
	395	+ err = add_usage_links(mod);
	396	+ if (err)
	397	+ goto out_unreg_modinfo_attrs;
	398	+
	399	+ add_sect_attrs(mod, info);
	400	+ add_notes_attrs(mod, info);
	401	+
	402	+ return 0;
	403	+
	404	+out_unreg_modinfo_attrs:
	405	+ module_remove_modinfo_attrs(mod, -1);
	406	+out_unreg_param:
	407	+ module_param_sysfs_remove(mod);
	408	+out_unreg_holders:
	409	+ kobject_put(mod->holders_dir);
	410	+out_unreg:
	411	+ mod_kobject_put(mod);
	412	+out:
	413	+ return err;
	414	+}
	415	+
	416	+static void mod_sysfs_fini(struct module *mod)
	417	+{
	418	+ remove_notes_attrs(mod);
	419	+ remove_sect_attrs(mod);
	420	+ mod_kobject_put(mod);
	421	+}
	422	+
	423	+void mod_sysfs_teardown(struct module *mod)
	424	+{
	425	+ del_usage_links(mod);
	426	+ module_remove_modinfo_attrs(mod, -1);
	427	+ module_param_sysfs_remove(mod);
	428	+ kobject_put(mod->mkobj.drivers_dir);
	429	+ kobject_put(mod->holders_dir);
	430	+ mod_sysfs_fini(mod);
	431	+}
	432	+
	433	+void init_param_lock(struct module *mod)
	434	+{
	435	+ mutex_init(&mod->param_lock);
	436	+}