/* * fs/nfsctl.c * * This should eventually move to userland. * */ #include <linux/types.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; struct vfsmount *mnt; int error; mnt = do_kern_mount("nfsd", 0, "nfsd", NULL); if (IS_ERR(mnt)) return (struct file *)mnt; error = vfs_path_lookup(mnt->mnt_root, mnt, name, 0, &nd); mntput(mnt); /* drop do_kern_mount reference */ 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.path.dentry, nd.path.mnt, flags); path_put(&nd.path); 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) return -EINVAL; if (cmd < 0 || cmd >= ARRAY_SIZE(map) || !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; }