1 /*
2 * linux/fs/ioctl.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7 #include <linux/mm.h>
8 #include <linux/smp_lock.h>
9 #include <linux/file.h>
10
11 #include <asm/uaccess.h>
12 #include <asm/ioctls.h>
13
file_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)14 static int file_ioctl(struct file *filp,unsigned int cmd,unsigned long arg)
15 {
16 int error;
17 int block;
18 struct inode * inode = filp->f_dentry->d_inode;
19
20 switch (cmd) {
21 case FIBMAP:
22 {
23 struct address_space *mapping = inode->i_mapping;
24 int res;
25 /* do we support this mess? */
26 if (!mapping->a_ops->bmap)
27 return -EINVAL;
28 if (!capable(CAP_SYS_RAWIO))
29 return -EPERM;
30 if ((error = get_user(block, (int *) arg)) != 0)
31 return error;
32
33 res = mapping->a_ops->bmap(mapping, block);
34 return put_user(res, (int *) arg);
35 }
36 case FIGETBSZ:
37 if (inode->i_sb == NULL)
38 return -EBADF;
39 return put_user(inode->i_sb->s_blocksize, (int *) arg);
40 case FIONREAD:
41 return put_user(inode->i_size - filp->f_pos, (int *) arg);
42 }
43 if (filp->f_op && filp->f_op->ioctl)
44 return filp->f_op->ioctl(inode, filp, cmd, arg);
45 return -ENOTTY;
46 }
47
48
sys_ioctl(unsigned int fd,unsigned int cmd,unsigned long arg)49 asmlinkage long sys_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
50 {
51 struct file * filp;
52 unsigned int flag;
53 int on, error = -EBADF;
54
55 filp = fget(fd);
56 if (!filp)
57 goto out;
58 error = 0;
59 lock_kernel();
60 switch (cmd) {
61 case FIOCLEX:
62 set_close_on_exec(fd, 1);
63 break;
64
65 case FIONCLEX:
66 set_close_on_exec(fd, 0);
67 break;
68
69 case FIONBIO:
70 if ((error = get_user(on, (int *)arg)) != 0)
71 break;
72 flag = O_NONBLOCK;
73 #ifdef __sparc__
74 /* SunOS compatibility item. */
75 if(O_NONBLOCK != O_NDELAY)
76 flag |= O_NDELAY;
77 #endif
78 if (on)
79 filp->f_flags |= flag;
80 else
81 filp->f_flags &= ~flag;
82 break;
83
84 case FIOASYNC:
85 if ((error = get_user(on, (int *)arg)) != 0)
86 break;
87 flag = on ? FASYNC : 0;
88
89 /* Did FASYNC state change ? */
90 if ((flag ^ filp->f_flags) & FASYNC) {
91 if (filp->f_op && filp->f_op->fasync)
92 error = filp->f_op->fasync(fd, filp, on);
93 else error = -ENOTTY;
94 }
95 if (error != 0)
96 break;
97
98 if (on)
99 filp->f_flags |= FASYNC;
100 else
101 filp->f_flags &= ~FASYNC;
102 break;
103
104 case FIOQSIZE:
105 if (S_ISDIR(filp->f_dentry->d_inode->i_mode) ||
106 S_ISREG(filp->f_dentry->d_inode->i_mode) ||
107 S_ISLNK(filp->f_dentry->d_inode->i_mode)) {
108 loff_t res = inode_get_bytes(filp->f_dentry->d_inode);
109 error = copy_to_user((loff_t *)arg, &res, sizeof(res)) ? -EFAULT : 0;
110 }
111 else
112 error = -ENOTTY;
113 break;
114 default:
115 error = -ENOTTY;
116 if (S_ISREG(filp->f_dentry->d_inode->i_mode))
117 error = file_ioctl(filp, cmd, arg);
118 else if (filp->f_op && filp->f_op->ioctl)
119 error = filp->f_op->ioctl(filp->f_dentry->d_inode, filp, cmd, arg);
120 }
121 unlock_kernel();
122 fput(filp);
123
124 out:
125 return error;
126 }
127