blob: b1acbd6ab6fb07c857b910f518a53736d8bd3631 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * fs/nfsctl.c
3 *
4 * This should eventually move to userland.
5 *
6 */
Alan Cox715b49e2006-01-18 17:44:07 -08007#include <linux/types.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07008#include <linux/file.h>
9#include <linux/fs.h>
10#include <linux/sunrpc/svc.h>
11#include <linux/nfsd/nfsd.h>
12#include <linux/nfsd/syscall.h>
Randy Dunlap9789cfe2008-11-19 11:46:46 -080013#include <linux/cred.h>
14#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#include <linux/linkage.h>
16#include <linux/namei.h>
17#include <linux/mount.h>
18#include <linux/syscalls.h>
19#include <asm/uaccess.h>
20
21/*
22 * open a file on nfsd fs
23 */
24
25static struct file *do_open(char *name, int flags)
26{
27 struct nameidata nd;
Josef 'Jeff' Sipek16b62872007-07-19 01:48:21 -070028 struct vfsmount *mnt;
Linus Torvalds1da177e2005-04-16 15:20:36 -070029 int error;
30
Josef 'Jeff' Sipek16b62872007-07-19 01:48:21 -070031 mnt = do_kern_mount("nfsd", 0, "nfsd", NULL);
32 if (IS_ERR(mnt))
33 return (struct file *)mnt;
Linus Torvalds1da177e2005-04-16 15:20:36 -070034
Josef 'Jeff' Sipek16b62872007-07-19 01:48:21 -070035 error = vfs_path_lookup(mnt->mnt_root, mnt, name, 0, &nd);
36 mntput(mnt); /* drop do_kern_mount reference */
Linus Torvalds1da177e2005-04-16 15:20:36 -070037 if (error)
38 return ERR_PTR(error);
39
40 if (flags == O_RDWR)
41 error = may_open(&nd,MAY_READ|MAY_WRITE,FMODE_READ|FMODE_WRITE);
42 else
43 error = may_open(&nd, MAY_WRITE, FMODE_WRITE);
44
45 if (!error)
David Howells745ca242008-11-14 10:39:22 +110046 return dentry_open(nd.path.dentry, nd.path.mnt, flags,
47 current_cred());
Linus Torvalds1da177e2005-04-16 15:20:36 -070048
Jan Blunck1d957f92008-02-14 19:34:35 -080049 path_put(&nd.path);
Linus Torvalds1da177e2005-04-16 15:20:36 -070050 return ERR_PTR(error);
51}
52
53static struct {
54 char *name; int wsize; int rsize;
55} map[] = {
56 [NFSCTL_SVC] = {
57 .name = ".svc",
58 .wsize = sizeof(struct nfsctl_svc)
59 },
60 [NFSCTL_ADDCLIENT] = {
61 .name = ".add",
62 .wsize = sizeof(struct nfsctl_client)
63 },
64 [NFSCTL_DELCLIENT] = {
65 .name = ".del",
66 .wsize = sizeof(struct nfsctl_client)
67 },
68 [NFSCTL_EXPORT] = {
69 .name = ".export",
70 .wsize = sizeof(struct nfsctl_export)
71 },
72 [NFSCTL_UNEXPORT] = {
73 .name = ".unexport",
74 .wsize = sizeof(struct nfsctl_export)
75 },
76 [NFSCTL_GETFD] = {
77 .name = ".getfd",
78 .wsize = sizeof(struct nfsctl_fdparm),
79 .rsize = NFS_FHSIZE
80 },
81 [NFSCTL_GETFS] = {
82 .name = ".getfs",
83 .wsize = sizeof(struct nfsctl_fsparm),
84 .rsize = sizeof(struct knfsd_fh)
85 },
86};
87
88long
89asmlinkage sys_nfsservctl(int cmd, struct nfsctl_arg __user *arg, void __user *res)
90{
91 struct file *file;
92 void __user *p = &arg->u;
93 int version;
94 int err;
95
96 if (copy_from_user(&version, &arg->ca_version, sizeof(int)))
97 return -EFAULT;
98
Peter Staubach85c69322006-03-16 23:04:02 -080099 if (version != NFSCTL_VERSION)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101
Tobias Klausere8c96f82006-03-24 03:15:34 -0800102 if (cmd < 0 || cmd >= ARRAY_SIZE(map) || !map[cmd].name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 return -EINVAL;
104
105 file = do_open(map[cmd].name, map[cmd].rsize ? O_RDWR : O_WRONLY);
106 if (IS_ERR(file))
107 return PTR_ERR(file);
108 err = file->f_op->write(file, p, map[cmd].wsize, &file->f_pos);
109 if (err >= 0 && map[cmd].rsize)
110 err = file->f_op->read(file, res, map[cmd].rsize, &file->f_pos);
111 if (err >= 0)
112 err = 0;
113 fput(file);
114 return err;
115}