ia64/linux-2.6.18-xen.hg

view fs/nfsctl.c @ 0:831230e53067

Import 2.6.18 from kernel.org tarball.
author Ian Campbell <ian.campbell@xensource.com>
date Wed Apr 11 14:15:44 2007 +0100 (2007-04-11)
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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/sunrpc/svc.h>
11 #include <linux/nfsd/nfsd.h>
12 #include <linux/nfsd/syscall.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>
19 /*
20 * open a file on nfsd fs
21 */
23 static struct file *do_open(char *name, int flags)
24 {
25 struct nameidata nd;
26 int error;
28 nd.mnt = do_kern_mount("nfsd", 0, "nfsd", NULL);
30 if (IS_ERR(nd.mnt))
31 return (struct file *)nd.mnt;
33 nd.dentry = dget(nd.mnt->mnt_root);
34 nd.last_type = LAST_ROOT;
35 nd.flags = 0;
36 nd.depth = 0;
38 error = path_walk(name, &nd);
39 if (error)
40 return ERR_PTR(error);
42 if (flags == O_RDWR)
43 error = may_open(&nd,MAY_READ|MAY_WRITE,FMODE_READ|FMODE_WRITE);
44 else
45 error = may_open(&nd, MAY_WRITE, FMODE_WRITE);
47 if (!error)
48 return dentry_open(nd.dentry, nd.mnt, flags);
50 path_release(&nd);
51 return ERR_PTR(error);
52 }
54 static 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 };
89 long
90 asmlinkage 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;
97 if (copy_from_user(&version, &arg->ca_version, sizeof(int)))
98 return -EFAULT;
100 if (version != NFSCTL_VERSION)
101 return -EINVAL;
103 if (cmd < 0 || cmd >= ARRAY_SIZE(map) || !map[cmd].name)
104 return -EINVAL;
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 }