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path: root/fs/sysfs/mount.c
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Diffstat (limited to 'fs/sysfs/mount.c')
-rw-r--r--fs/sysfs/mount.c184
1 files changed, 25 insertions, 159 deletions
diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c
index 834ec2cdb7a..6211230814f 100644
--- a/fs/sysfs/mount.c
+++ b/fs/sysfs/mount.c
@@ -14,146 +14,41 @@
#include <linux/fs.h>
#include <linux/mount.h>
-#include <linux/pagemap.h>
#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/magic.h>
-#include <linux/slab.h>
#include <linux/user_namespace.h>
#include "sysfs.h"
-
-static struct vfsmount *sysfs_mnt;
-struct kmem_cache *sysfs_dir_cachep;
-
-static const struct super_operations sysfs_ops = {
- .statfs = simple_statfs,
- .drop_inode = generic_delete_inode,
- .evict_inode = sysfs_evict_inode,
-};
-
-struct sysfs_dirent sysfs_root = {
- .s_name = "",
- .s_count = ATOMIC_INIT(1),
- .s_flags = SYSFS_DIR | (KOBJ_NS_TYPE_NONE << SYSFS_NS_TYPE_SHIFT),
- .s_mode = S_IFDIR | S_IRUGO | S_IXUGO,
- .s_ino = 1,
-};
-
-static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
-{
- struct inode *inode;
- struct dentry *root;
-
- sb->s_blocksize = PAGE_CACHE_SIZE;
- sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
- sb->s_magic = SYSFS_MAGIC;
- sb->s_op = &sysfs_ops;
- sb->s_time_gran = 1;
-
- /* get root inode, initialize and unlock it */
- mutex_lock(&sysfs_mutex);
- inode = sysfs_get_inode(sb, &sysfs_root);
- mutex_unlock(&sysfs_mutex);
- if (!inode) {
- pr_debug("sysfs: could not get root inode\n");
- return -ENOMEM;
- }
-
- /* instantiate and link root dentry */
- root = d_make_root(inode);
- if (!root) {
- pr_debug("%s: could not get root dentry!\n", __func__);
- return -ENOMEM;
- }
- root->d_fsdata = &sysfs_root;
- sb->s_root = root;
- sb->s_d_op = &sysfs_dentry_ops;
- return 0;
-}
-
-static int sysfs_test_super(struct super_block *sb, void *data)
-{
- struct sysfs_super_info *sb_info = sysfs_info(sb);
- struct sysfs_super_info *info = data;
- enum kobj_ns_type type;
- int found = 1;
-
- for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++) {
- if (sb_info->ns[type] != info->ns[type])
- found = 0;
- }
- return found;
-}
-
-static int sysfs_set_super(struct super_block *sb, void *data)
-{
- int error;
- error = set_anon_super(sb, data);
- if (!error)
- sb->s_fs_info = data;
- return error;
-}
-
-static void free_sysfs_super_info(struct sysfs_super_info *info)
-{
- int type;
- for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++)
- kobj_ns_drop(type, info->ns[type]);
- kfree(info);
-}
+static struct kernfs_root *sysfs_root;
+struct kernfs_node *sysfs_root_kn;
static struct dentry *sysfs_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
- struct sysfs_super_info *info;
- enum kobj_ns_type type;
- struct super_block *sb;
- int error;
+ struct dentry *root;
+ void *ns;
if (!(flags & MS_KERNMOUNT)) {
if (!capable(CAP_SYS_ADMIN) && !fs_fully_visible(fs_type))
return ERR_PTR(-EPERM);
- for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++) {
- if (!kobj_ns_current_may_mount(type))
- return ERR_PTR(-EPERM);
- }
- }
-
- info = kzalloc(sizeof(*info), GFP_KERNEL);
- if (!info)
- return ERR_PTR(-ENOMEM);
-
- for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++)
- info->ns[type] = kobj_ns_grab_current(type);
-
- sb = sget(fs_type, sysfs_test_super, sysfs_set_super, flags, info);
- if (IS_ERR(sb) || sb->s_fs_info != info)
- free_sysfs_super_info(info);
- if (IS_ERR(sb))
- return ERR_CAST(sb);
- if (!sb->s_root) {
- error = sysfs_fill_super(sb, data, flags & MS_SILENT ? 1 : 0);
- if (error) {
- deactivate_locked_super(sb);
- return ERR_PTR(error);
- }
- sb->s_flags |= MS_ACTIVE;
+ if (!kobj_ns_current_may_mount(KOBJ_NS_TYPE_NET))
+ return ERR_PTR(-EPERM);
}
- return dget(sb->s_root);
+ ns = kobj_ns_grab_current(KOBJ_NS_TYPE_NET);
+ root = kernfs_mount_ns(fs_type, flags, sysfs_root, ns);
+ if (IS_ERR(root))
+ kobj_ns_drop(KOBJ_NS_TYPE_NET, ns);
+ return root;
}
static void sysfs_kill_sb(struct super_block *sb)
{
- struct sysfs_super_info *info = sysfs_info(sb);
- /* Remove the superblock from fs_supers/s_instances
- * so we can't find it, before freeing sysfs_super_info.
- */
- kill_anon_super(sb);
- free_sysfs_super_info(info);
+ void *ns = (void *)kernfs_super_ns(sb);
+
+ kernfs_kill_sb(sb);
+ kobj_ns_drop(KOBJ_NS_TYPE_NET, ns);
}
static struct file_system_type sysfs_fs_type = {
@@ -165,48 +60,19 @@ static struct file_system_type sysfs_fs_type = {
int __init sysfs_init(void)
{
- int err = -ENOMEM;
+ int err;
- sysfs_dir_cachep = kmem_cache_create("sysfs_dir_cache",
- sizeof(struct sysfs_dirent),
- 0, 0, NULL);
- if (!sysfs_dir_cachep)
- goto out;
+ sysfs_root = kernfs_create_root(NULL, NULL);
+ if (IS_ERR(sysfs_root))
+ return PTR_ERR(sysfs_root);
- err = sysfs_inode_init();
- if (err)
- goto out_err;
+ sysfs_root_kn = sysfs_root->kn;
err = register_filesystem(&sysfs_fs_type);
- if (!err) {
- sysfs_mnt = kern_mount(&sysfs_fs_type);
- if (IS_ERR(sysfs_mnt)) {
- printk(KERN_ERR "sysfs: could not mount!\n");
- err = PTR_ERR(sysfs_mnt);
- sysfs_mnt = NULL;
- unregister_filesystem(&sysfs_fs_type);
- goto out_err;
- }
- } else
- goto out_err;
-out:
- return err;
-out_err:
- kmem_cache_destroy(sysfs_dir_cachep);
- sysfs_dir_cachep = NULL;
- goto out;
-}
-
-#undef sysfs_get
-struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
-{
- return __sysfs_get(sd);
-}
-EXPORT_SYMBOL_GPL(sysfs_get);
+ if (err) {
+ kernfs_destroy_root(sysfs_root);
+ return err;
+ }
-#undef sysfs_put
-void sysfs_put(struct sysfs_dirent *sd)
-{
- __sysfs_put(sd);
+ return 0;
}
-EXPORT_SYMBOL_GPL(sysfs_put);