1 files changed, 118 insertions, 0 deletions
diff --git a/fs/nfsctl.c b/fs/nfsctl.c
new file mode 100644
index 000000000000..0b14938b5b62
--- /dev/null
+++ b/fs/nfsctl.c
@@ -0,0 +1,118 @@
+/*
+ *	fs/nfsctl.c
+ *
+ *	This should eventually move to userland.
+ *
+ */
+#include <linux/config.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/sunrpc/svc.h>
+#include <linux/nfsd/nfsd.h>
+#include <linux/nfsd/syscall.h>
+#include <linux/linkage.h>
+#include <linux/namei.h>
+#include <linux/mount.h>
+#include <linux/syscalls.h>
+#include <asm/uaccess.h>
+
+/*
+ * open a file on nfsd fs
+ */
+
+static struct file *do_open(char *name, int flags)
+{
+	struct nameidata nd;
+	int error;
+
+	nd.mnt = do_kern_mount("nfsd", 0, "nfsd", NULL);
+
+	if (IS_ERR(nd.mnt))
+		return (struct file *)nd.mnt;
+
+	nd.dentry = dget(nd.mnt->mnt_root);
+	nd.last_type = LAST_ROOT;
+	nd.flags = 0;
+	nd.depth = 0;
+
+	error = path_walk(name, &nd);
+	if (error)
+		return ERR_PTR(error);
+
+	if (flags == O_RDWR)
+		error = may_open(&nd,MAY_READ|MAY_WRITE,FMODE_READ|FMODE_WRITE);
+	else
+		error = may_open(&nd, MAY_WRITE, FMODE_WRITE);
+
+	if (!error)
+		return dentry_open(nd.dentry, nd.mnt, flags);
+
+	path_release(&nd);
+	return ERR_PTR(error);
+}
+
+static struct {
+	char *name; int wsize; int rsize;
+} map[] = {
+	[NFSCTL_SVC] = {
+		.name	= ".svc",
+		.wsize	= sizeof(struct nfsctl_svc)
+	},
+	[NFSCTL_ADDCLIENT] = {
+		.name	= ".add",
+		.wsize	= sizeof(struct nfsctl_client)
+	},
+	[NFSCTL_DELCLIENT] = {
+		.name	= ".del",
+		.wsize	= sizeof(struct nfsctl_client)
+	},
+	[NFSCTL_EXPORT] = {
+		.name	= ".export",
+		.wsize	= sizeof(struct nfsctl_export)
+	},
+	[NFSCTL_UNEXPORT] = {
+		.name	= ".unexport",
+		.wsize	= sizeof(struct nfsctl_export)
+	},
+	[NFSCTL_GETFD] = {
+		.name	= ".getfd",
+		.wsize	= sizeof(struct nfsctl_fdparm),
+		.rsize	= NFS_FHSIZE
+	},
+	[NFSCTL_GETFS] = {
+		.name	= ".getfs",
+		.wsize	= sizeof(struct nfsctl_fsparm),
+		.rsize	= sizeof(struct knfsd_fh)
+	},
+};
+
+long
+asmlinkage sys_nfsservctl(int cmd, struct nfsctl_arg __user *arg, void __user *res)
+{
+	struct file *file;
+	void __user *p = &arg->u;
+	int version;
+	int err;
+
+	if (copy_from_user(&version, &arg->ca_version, sizeof(int)))
+		return -EFAULT;
+
+	if (version != NFSCTL_VERSION) {
+		printk(KERN_WARNING "nfsd: incompatible version in syscall.\n");
+		return -EINVAL;
+	}
+
+	if (cmd < 0 || cmd >= sizeof(map)/sizeof(map[0]) || !map[cmd].name)
+		return -EINVAL;
+
+	file = do_open(map[cmd].name, map[cmd].rsize ? O_RDWR : O_WRONLY);	
+	if (IS_ERR(file))
+		return PTR_ERR(file);
+	err = file->f_op->write(file, p, map[cmd].wsize, &file->f_pos);
+	if (err >= 0 && map[cmd].rsize)
+		err = file->f_op->read(file, res, map[cmd].rsize, &file->f_pos);
+	if (err >= 0)
+		err = 0;
+	fput(file);
+	return err;
+}