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;
+}