tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * fs/nfsctl.c
3 *
4 * This should eventually move to userland.
5 *
6 */
7#include <linux/types.h>
8#include <linux/file.h>
9#include <linux/fs.h>
10#include <linux/nfsd/syscall.h>
11#include <linux/cred.h>
12#include <linux/sched.h>
13#include <linux/linkage.h>
14#include <linux/namei.h>
15#include <linux/mount.h>
16#include <linux/syscalls.h>
17#include <asm/uaccess.h>
18
19/*
20 * open a file on nfsd fs
21 */
22
23static struct file *do_open(char *name, int flags)
24{
25 struct vfsmount *mnt;
26 struct file *file;
27
28 mnt = do_kern_mount("nfsd", 0, "nfsd", NULL);
29 if (IS_ERR(mnt))
30 return (struct file *)mnt;
31
32 file = file_open_root(mnt->mnt_root, mnt, name, flags);
33
34 mntput(mnt); /* drop do_kern_mount reference */
35 return file;
36}
37
38static struct {
39 char *name; int wsize; int rsize;
40} map[] = {
41 [NFSCTL_SVC] = {
42 .name = ".svc",
43 .wsize = sizeof(struct nfsctl_svc)
44 },
45 [NFSCTL_ADDCLIENT] = {
46 .name = ".add",
47 .wsize = sizeof(struct nfsctl_client)
48 },
49 [NFSCTL_DELCLIENT] = {
50 .name = ".del",
51 .wsize = sizeof(struct nfsctl_client)
52 },
53 [NFSCTL_EXPORT] = {
54 .name = ".export",
55 .wsize = sizeof(struct nfsctl_export)
56 },
57 [NFSCTL_UNEXPORT] = {
58 .name = ".unexport",
59 .wsize = sizeof(struct nfsctl_export)
60 },
61 [NFSCTL_GETFD] = {
62 .name = ".getfd",
63 .wsize = sizeof(struct nfsctl_fdparm),
64 .rsize = NFS_FHSIZE
65 },
66 [NFSCTL_GETFS] = {
67 .name = ".getfs",
68 .wsize = sizeof(struct nfsctl_fsparm),
69 .rsize = sizeof(struct knfsd_fh)
70 },
71};
72
73SYSCALL_DEFINE3(nfsservctl, int, cmd, struct nfsctl_arg __user *, arg,
74 void __user *, res)
75{
76 struct file *file;
77 void __user *p = &arg->u;
78 int version;
79 int err;
80
81 if (copy_from_user(&version, &arg->ca_version, sizeof(int)))
82 return -EFAULT;
83
84 if (version != NFSCTL_VERSION)
85 return -EINVAL;
86
87 if (cmd < 0 || cmd >= ARRAY_SIZE(map) || !map[cmd].name)
88 return -EINVAL;
89
90 file = do_open(map[cmd].name, map[cmd].rsize ? O_RDWR : O_WRONLY);
91 if (IS_ERR(file))
92 return PTR_ERR(file);
93 err = file->f_op->write(file, p, map[cmd].wsize, &file->f_pos);
94 if (err >= 0 && map[cmd].rsize)
95 err = file->f_op->read(file, res, map[cmd].rsize, &file->f_pos);
96 if (err >= 0)
97 err = 0;
98 fput(file);
99 return err;
100}