blob: 4b7660b09ac0679cd79481bc14727dbd4888eeb5 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/ioctl.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
Linus Torvalds1da177e2005-04-16 15:20:36 -07007#include <linux/syscalls.h>
8#include <linux/mm.h>
9#include <linux/smp_lock.h>
Randy Dunlap16f7e0f2006-01-11 12:17:46 -080010#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <linux/file.h>
12#include <linux/fs.h>
13#include <linux/security.h>
14#include <linux/module.h>
15
16#include <asm/uaccess.h>
17#include <asm/ioctls.h>
18
19static long do_ioctl(struct file *filp, unsigned int cmd,
20 unsigned long arg)
21{
22 int error = -ENOTTY;
23
24 if (!filp->f_op)
25 goto out;
26
27 if (filp->f_op->unlocked_ioctl) {
28 error = filp->f_op->unlocked_ioctl(filp, cmd, arg);
29 if (error == -ENOIOCTLCMD)
30 error = -EINVAL;
31 goto out;
32 } else if (filp->f_op->ioctl) {
33 lock_kernel();
34 error = filp->f_op->ioctl(filp->f_dentry->d_inode,
35 filp, cmd, arg);
36 unlock_kernel();
37 }
38
39 out:
40 return error;
41}
42
43static int file_ioctl(struct file *filp, unsigned int cmd,
44 unsigned long arg)
45{
46 int error;
47 int block;
48 struct inode * inode = filp->f_dentry->d_inode;
49 int __user *p = (int __user *)arg;
50
51 switch (cmd) {
52 case FIBMAP:
53 {
54 struct address_space *mapping = filp->f_mapping;
55 int res;
56 /* do we support this mess? */
57 if (!mapping->a_ops->bmap)
58 return -EINVAL;
59 if (!capable(CAP_SYS_RAWIO))
60 return -EPERM;
61 if ((error = get_user(block, p)) != 0)
62 return error;
63
64 lock_kernel();
65 res = mapping->a_ops->bmap(mapping, block);
66 unlock_kernel();
67 return put_user(res, p);
68 }
69 case FIGETBSZ:
70 if (inode->i_sb == NULL)
71 return -EBADF;
72 return put_user(inode->i_sb->s_blocksize, p);
73 case FIONREAD:
74 return put_user(i_size_read(inode) - filp->f_pos, p);
75 }
76
77 return do_ioctl(filp, cmd, arg);
78}
79
80/*
81 * When you add any new common ioctls to the switches above and below
82 * please update compat_sys_ioctl() too.
83 *
84 * vfs_ioctl() is not for drivers and not intended to be EXPORT_SYMBOL()'d.
85 * It's just a simple helper for sys_ioctl and compat_sys_ioctl.
86 */
87int vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd, unsigned long arg)
88{
89 unsigned int flag;
90 int on, error = 0;
91
92 switch (cmd) {
93 case FIOCLEX:
94 set_close_on_exec(fd, 1);
95 break;
96
97 case FIONCLEX:
98 set_close_on_exec(fd, 0);
99 break;
100
101 case FIONBIO:
102 if ((error = get_user(on, (int __user *)arg)) != 0)
103 break;
104 flag = O_NONBLOCK;
105#ifdef __sparc__
106 /* SunOS compatibility item. */
107 if(O_NONBLOCK != O_NDELAY)
108 flag |= O_NDELAY;
109#endif
110 if (on)
111 filp->f_flags |= flag;
112 else
113 filp->f_flags &= ~flag;
114 break;
115
116 case FIOASYNC:
117 if ((error = get_user(on, (int __user *)arg)) != 0)
118 break;
119 flag = on ? FASYNC : 0;
120
121 /* Did FASYNC state change ? */
122 if ((flag ^ filp->f_flags) & FASYNC) {
123 if (filp->f_op && filp->f_op->fasync) {
124 lock_kernel();
125 error = filp->f_op->fasync(fd, filp, on);
126 unlock_kernel();
127 }
128 else error = -ENOTTY;
129 }
130 if (error != 0)
131 break;
132
133 if (on)
134 filp->f_flags |= FASYNC;
135 else
136 filp->f_flags &= ~FASYNC;
137 break;
138
139 case FIOQSIZE:
140 if (S_ISDIR(filp->f_dentry->d_inode->i_mode) ||
141 S_ISREG(filp->f_dentry->d_inode->i_mode) ||
142 S_ISLNK(filp->f_dentry->d_inode->i_mode)) {
143 loff_t res = inode_get_bytes(filp->f_dentry->d_inode);
144 error = copy_to_user((loff_t __user *)arg, &res, sizeof(res)) ? -EFAULT : 0;
145 }
146 else
147 error = -ENOTTY;
148 break;
149 default:
150 if (S_ISREG(filp->f_dentry->d_inode->i_mode))
151 error = file_ioctl(filp, cmd, arg);
152 else
153 error = do_ioctl(filp, cmd, arg);
154 break;
155 }
156 return error;
157}
158
159asmlinkage long sys_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
160{
161 struct file * filp;
162 int error = -EBADF;
163 int fput_needed;
164
165 filp = fget_light(fd, &fput_needed);
166 if (!filp)
167 goto out;
168
169 error = security_file_ioctl(filp, cmd, arg);
170 if (error)
171 goto out_fput;
172
173 error = vfs_ioctl(filp, fd, cmd, arg);
174 out_fput:
175 fput_light(filp, fput_needed);
176 out:
177 return error;
178}
179
180/*
181 * Platforms implementing 32 bit compatibility ioctl handlers in
182 * modules need this exported
183 */
184#ifdef CONFIG_COMPAT
185EXPORT_SYMBOL(sys_ioctl);
186#endif