blob: b27451909dff0d17b2f148adad84f964214bac83 [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)
Christoph Hellwig3fb64192008-10-24 09:58:10 +020041 error = may_open(&nd.path, MAY_READ|MAY_WRITE,
42 FMODE_READ|FMODE_WRITE);
Linus Torvalds1da177e2005-04-16 15:20:36 -070043 else
Christoph Hellwig3fb64192008-10-24 09:58:10 +020044 error = may_open(&nd.path, MAY_WRITE, FMODE_WRITE);
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
46 if (!error)
David Howells745ca242008-11-14 10:39:22 +110047 return dentry_open(nd.path.dentry, nd.path.mnt, flags,
48 current_cred());
Linus Torvalds1da177e2005-04-16 15:20:36 -070049
Jan Blunck1d957f92008-02-14 19:34:35 -080050 path_put(&nd.path);
Linus Torvalds1da177e2005-04-16 15:20:36 -070051 return ERR_PTR(error);
52}
53
54static struct {
55 char *name; int wsize; int rsize;
56} map[] = {
57 [NFSCTL_SVC] = {
58 .name = ".svc",
59 .wsize = sizeof(struct nfsctl_svc)
60 },
61 [NFSCTL_ADDCLIENT] = {
62 .name = ".add",
63 .wsize = sizeof(struct nfsctl_client)
64 },
65 [NFSCTL_DELCLIENT] = {
66 .name = ".del",
67 .wsize = sizeof(struct nfsctl_client)
68 },
69 [NFSCTL_EXPORT] = {
70 .name = ".export",
71 .wsize = sizeof(struct nfsctl_export)
72 },
73 [NFSCTL_UNEXPORT] = {
74 .name = ".unexport",
75 .wsize = sizeof(struct nfsctl_export)
76 },
77 [NFSCTL_GETFD] = {
78 .name = ".getfd",
79 .wsize = sizeof(struct nfsctl_fdparm),
80 .rsize = NFS_FHSIZE
81 },
82 [NFSCTL_GETFS] = {
83 .name = ".getfs",
84 .wsize = sizeof(struct nfsctl_fsparm),
85 .rsize = sizeof(struct knfsd_fh)
86 },
87};
88
89long
90asmlinkage sys_nfsservctl(int cmd, struct nfsctl_arg __user *arg, void __user *res)
91{
92 struct file *file;
93 void __user *p = &arg->u;
94 int version;
95 int err;
96
97 if (copy_from_user(&version, &arg->ca_version, sizeof(int)))
98 return -EFAULT;
99
Peter Staubach85c69322006-03-16 23:04:02 -0800100 if (version != NFSCTL_VERSION)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102
Tobias Klausere8c96f82006-03-24 03:15:34 -0800103 if (cmd < 0 || cmd >= ARRAY_SIZE(map) || !map[cmd].name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104 return -EINVAL;
105
106 file = do_open(map[cmd].name, map[cmd].rsize ? O_RDWR : O_WRONLY);
107 if (IS_ERR(file))
108 return PTR_ERR(file);
109 err = file->f_op->write(file, p, map[cmd].wsize, &file->f_pos);
110 if (err >= 0 && map[cmd].rsize)
111 err = file->f_op->read(file, res, map[cmd].rsize, &file->f_pos);
112 if (err >= 0)
113 err = 0;
114 fput(file);
115 return err;
116}