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gerrit-public.fairphone.software / fp2-dev / kernel / msm / 1e8c573933fd7975679766850252ad08667e5ca4 / . / fs / ioctl.c
blob: f8aeec3ca10c20985146e292023e5554b2290765 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]1/*
2 * linux/fs/ioctl.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7#include <linux/config.h>
8#include <linux/syscalls.h>
9#include <linux/mm.h>
10#include <linux/smp_lock.h>
Randy Dunlap16f7e0f2006-01-11 12:17:46 -0800[diff] [blame]11#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]12#include <linux/file.h>
13#include <linux/fs.h>
14#include <linux/security.h>
15#include <linux/module.h>
16
17#include <asm/uaccess.h>
18#include <asm/ioctls.h>
19
20static long do_ioctl(struct file *filp, unsigned int cmd,
21 unsigned long arg)
22{
23 int error = -ENOTTY;
24
25 if (!filp->f_op)
26 goto out;
27
28 if (filp->f_op->unlocked_ioctl) {
29 error = filp->f_op->unlocked_ioctl(filp, cmd, arg);
30 if (error == -ENOIOCTLCMD)
31 error = -EINVAL;
32 goto out;
33 } else if (filp->f_op->ioctl) {
34 lock_kernel();
35 error = filp->f_op->ioctl(filp->f_dentry->d_inode,
36 filp, cmd, arg);
37 unlock_kernel();
38 }
39
40 out:
41 return error;
42}
43
44static int file_ioctl(struct file *filp, unsigned int cmd,
45 unsigned long arg)
46{
47 int error;
48 int block;
49 struct inode * inode = filp->f_dentry->d_inode;
50 int __user *p = (int __user *)arg;
51
52 switch (cmd) {
53 case FIBMAP:
54 {
55 struct address_space *mapping = filp->f_mapping;
56 int res;
57 /* do we support this mess? */
58 if (!mapping->a_ops->bmap)
59 return -EINVAL;
60 if (!capable(CAP_SYS_RAWIO))
61 return -EPERM;
62 if ((error = get_user(block, p)) != 0)
63 return error;
64
65 lock_kernel();
66 res = mapping->a_ops->bmap(mapping, block);
67 unlock_kernel();
68 return put_user(res, p);
69 }
70 case FIGETBSZ:
71 if (inode->i_sb == NULL)
72 return -EBADF;
73 return put_user(inode->i_sb->s_blocksize, p);
74 case FIONREAD:
75 return put_user(i_size_read(inode) - filp->f_pos, p);
76 }
77
78 return do_ioctl(filp, cmd, arg);
79}
80
81/*
82 * When you add any new common ioctls to the switches above and below
83 * please update compat_sys_ioctl() too.
84 *
85 * vfs_ioctl() is not for drivers and not intended to be EXPORT_SYMBOL()'d.
86 * It's just a simple helper for sys_ioctl and compat_sys_ioctl.
87 */
88int vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd, unsigned long arg)
89{
90 unsigned int flag;
91 int on, error = 0;
92
93 switch (cmd) {
94 case FIOCLEX:
95 set_close_on_exec(fd, 1);
96 break;
97
98 case FIONCLEX:
99 set_close_on_exec(fd, 0);
100 break;
101
102 case FIONBIO:
103 if ((error = get_user(on, (int __user *)arg)) != 0)
104 break;
105 flag = O_NONBLOCK;
106#ifdef __sparc__
107 /* SunOS compatibility item. */
108 if(O_NONBLOCK != O_NDELAY)
109 flag |= O_NDELAY;
110#endif
111 if (on)
112 filp->f_flags |= flag;
113 else
114 filp->f_flags &= ~flag;
115 break;
116
117 case FIOASYNC:
118 if ((error = get_user(on, (int __user *)arg)) != 0)
119 break;
120 flag = on ? FASYNC : 0;
121
122 /* Did FASYNC state change ? */
123 if ((flag ^ filp->f_flags) & FASYNC) {
124 if (filp->f_op && filp->f_op->fasync) {
125 lock_kernel();
126 error = filp->f_op->fasync(fd, filp, on);
127 unlock_kernel();
128 }
129 else error = -ENOTTY;
130 }
131 if (error != 0)
132 break;
133
134 if (on)
135 filp->f_flags |= FASYNC;
136 else
137 filp->f_flags &= ~FASYNC;
138 break;
139
140 case FIOQSIZE:
141 if (S_ISDIR(filp->f_dentry->d_inode->i_mode) ||
142 S_ISREG(filp->f_dentry->d_inode->i_mode) ||
143 S_ISLNK(filp->f_dentry->d_inode->i_mode)) {
144 loff_t res = inode_get_bytes(filp->f_dentry->d_inode);
145 error = copy_to_user((loff_t __user *)arg, &res, sizeof(res)) ? -EFAULT : 0;
146 }
147 else
148 error = -ENOTTY;
149 break;
150 default:
151 if (S_ISREG(filp->f_dentry->d_inode->i_mode))
152 error = file_ioctl(filp, cmd, arg);
153 else
154 error = do_ioctl(filp, cmd, arg);
155 break;
156 }
157 return error;
158}
159
160asmlinkage long sys_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
161{
162 struct file * filp;
163 int error = -EBADF;
164 int fput_needed;
165
166 filp = fget_light(fd, &fput_needed);
167 if (!filp)
168 goto out;
169
170 error = security_file_ioctl(filp, cmd, arg);
171 if (error)
172 goto out_fput;
173
174 error = vfs_ioctl(filp, fd, cmd, arg);
175 out_fput:
176 fput_light(filp, fput_needed);
177 out:
178 return error;
179}
180
181/*
182 * Platforms implementing 32 bit compatibility ioctl handlers in
183 * modules need this exported
184 */
185#ifdef CONFIG_COMPAT
186EXPORT_SYMBOL(sys_ioctl);
187#endif