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-rw-r--r--fs/sysfs/mount.c107
1 files changed, 107 insertions, 0 deletions
diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c
new file mode 100644
index 000000000000..5c805bb1a4b7
--- /dev/null
+++ b/fs/sysfs/mount.c
@@ -0,0 +1,107 @@
+/*
+ * mount.c - operations for initializing and mounting sysfs.
+ */
+
+#define DEBUG
+
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/pagemap.h>
+#include <linux/init.h>
+
+#include "sysfs.h"
+
+/* Random magic number */
+#define SYSFS_MAGIC 0x62656572
+
+struct vfsmount *sysfs_mount;
+struct super_block * sysfs_sb = NULL;
+kmem_cache_t *sysfs_dir_cachep;
+
+static struct super_operations sysfs_ops = {
+ .statfs = simple_statfs,
+ .drop_inode = generic_delete_inode,
+};
+
+static struct sysfs_dirent sysfs_root = {
+ .s_sibling = LIST_HEAD_INIT(sysfs_root.s_sibling),
+ .s_children = LIST_HEAD_INIT(sysfs_root.s_children),
+ .s_element = NULL,
+ .s_type = SYSFS_ROOT,
+};
+
+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;
+ sysfs_sb = sb;
+
+ inode = sysfs_new_inode(S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO);
+ if (inode) {
+ inode->i_op = &sysfs_dir_inode_operations;
+ inode->i_fop = &sysfs_dir_operations;
+ /* directory inodes start off with i_nlink == 2 (for "." entry) */
+ inode->i_nlink++;
+ } else {
+ pr_debug("sysfs: could not get root inode\n");
+ return -ENOMEM;
+ }
+
+ root = d_alloc_root(inode);
+ if (!root) {
+ pr_debug("%s: could not get root dentry!\n",__FUNCTION__);
+ iput(inode);
+ return -ENOMEM;
+ }
+ root->d_fsdata = &sysfs_root;
+ sb->s_root = root;
+ return 0;
+}
+
+static struct super_block *sysfs_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data)
+{
+ return get_sb_single(fs_type, flags, data, sysfs_fill_super);
+}
+
+static struct file_system_type sysfs_fs_type = {
+ .name = "sysfs",
+ .get_sb = sysfs_get_sb,
+ .kill_sb = kill_litter_super,
+};
+
+int __init sysfs_init(void)
+{
+ int err = -ENOMEM;
+
+ sysfs_dir_cachep = kmem_cache_create("sysfs_dir_cache",
+ sizeof(struct sysfs_dirent),
+ 0, 0, NULL, NULL);
+ if (!sysfs_dir_cachep)
+ goto out;
+
+ err = register_filesystem(&sysfs_fs_type);
+ if (!err) {
+ sysfs_mount = kern_mount(&sysfs_fs_type);
+ if (IS_ERR(sysfs_mount)) {
+ printk(KERN_ERR "sysfs: could not mount!\n");
+ err = PTR_ERR(sysfs_mount);
+ sysfs_mount = 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;
+}