| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * fs/nfsctl.c |
| 3 | * |
| 4 | * This should eventually move to userland. |
| 5 | * |
| 6 | */ |
| 7 | #include <linux/config.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> |
| 18 | |
| 19 | /* |
| 20 | * open a file on nfsd fs |
| 21 | */ |
| 22 | |
| 23 | static struct file *do_open(char *name, int flags) |
| 24 | { |
| 25 | struct nameidata nd; |
| 26 | int error; |
| 27 | |
| 28 | nd.mnt = do_kern_mount("nfsd", 0, "nfsd", NULL); |
| 29 | |
| 30 | if (IS_ERR(nd.mnt)) |
| 31 | return (struct file *)nd.mnt; |
| 32 | |
| 33 | nd.dentry = dget(nd.mnt->mnt_root); |
| 34 | nd.last_type = LAST_ROOT; |
| 35 | nd.flags = 0; |
| 36 | nd.depth = 0; |
| 37 | |
| 38 | error = path_walk(name, &nd); |
| 39 | if (error) |
| 40 | return ERR_PTR(error); |
| 41 | |
| 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); |
| 46 | |
| 47 | if (!error) |
| 48 | return dentry_open(nd.dentry, nd.mnt, flags); |
| 49 | |
| 50 | path_release(&nd); |
| 51 | return ERR_PTR(error); |
| 52 | } |
| 53 | |
| 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 | }; |
| 88 | |
| 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; |
| 96 | |
| 97 | if (copy_from_user(&version, &arg->ca_version, sizeof(int))) |
| 98 | return -EFAULT; |
| 99 | |
| 100 | if (version != NFSCTL_VERSION) { |
| 101 | printk(KERN_WARNING "nfsd: incompatible version in syscall.\n"); |
| 102 | return -EINVAL; |
| 103 | } |
| 104 | |
| 105 | if (cmd < 0 || cmd >= sizeof(map)/sizeof(map[0]) || !map[cmd].name) |
| 106 | return -EINVAL; |
| 107 | |
| 108 | file = do_open(map[cmd].name, map[cmd].rsize ? O_RDWR : O_WRONLY); |
| 109 | if (IS_ERR(file)) |
| 110 | return PTR_ERR(file); |
| 111 | err = file->f_op->write(file, p, map[cmd].wsize, &file->f_pos); |
| 112 | if (err >= 0 && map[cmd].rsize) |
| 113 | err = file->f_op->read(file, res, map[cmd].rsize, &file->f_pos); |
| 114 | if (err >= 0) |
| 115 | err = 0; |
| 116 | fput(file); |
| 117 | return err; |
| 118 | } |