4 * Copyright (C) 1991, 1992 Linus Torvalds
7 #include <linux/syscalls.h>
9 #include <linux/smp_lock.h>
10 #include <linux/capability.h>
11 #include <linux/file.h>
13 #include <linux/security.h>
14 #include <linux/module.h>
15 #include <linux/uaccess.h>
17 #include <asm/ioctls.h>
20 * vfs_ioctl - call filesystem specific ioctl methods
21 * @filp: open file to invoke ioctl method on
22 * @cmd: ioctl command to execute
23 * @arg: command-specific argument for ioctl
25 * Invokes filesystem specific ->unlocked_ioctl, if one exists; otherwise
26 * invokes filesystem specific ->ioctl method. If neither method exists,
29 * Returns 0 on success, -errno on error.
31 static long vfs_ioctl(struct file *filp, unsigned int cmd,
39 if (filp->f_op->unlocked_ioctl) {
40 error = filp->f_op->unlocked_ioctl(filp, cmd, arg);
41 if (error == -ENOIOCTLCMD)
44 } else if (filp->f_op->ioctl) {
46 error = filp->f_op->ioctl(filp->f_path.dentry->d_inode,
55 static int ioctl_fibmap(struct file *filp, int __user *p)
57 struct address_space *mapping = filp->f_mapping;
60 /* do we support this mess? */
61 if (!mapping->a_ops->bmap)
63 if (!capable(CAP_SYS_RAWIO))
65 res = get_user(block, p);
69 res = mapping->a_ops->bmap(mapping, block);
71 return put_user(res, p);
74 static int file_ioctl(struct file *filp, unsigned int cmd,
77 struct inode *inode = filp->f_path.dentry->d_inode;
78 int __user *p = (int __user *)arg;
82 return ioctl_fibmap(filp, p);
84 return put_user(inode->i_sb->s_blocksize, p);
86 return put_user(i_size_read(inode) - filp->f_pos, p);
89 return vfs_ioctl(filp, cmd, arg);
92 static int ioctl_fionbio(struct file *filp, int __user *argp)
97 error = get_user(on, argp);
102 /* SunOS compatibility item. */
103 if (O_NONBLOCK != O_NDELAY)
107 filp->f_flags |= flag;
109 filp->f_flags &= ~flag;
113 static int ioctl_fioasync(unsigned int fd, struct file *filp,
119 error = get_user(on, argp);
122 flag = on ? FASYNC : 0;
124 /* Did FASYNC state change ? */
125 if ((flag ^ filp->f_flags) & FASYNC) {
126 if (filp->f_op && filp->f_op->fasync)
127 error = filp->f_op->fasync(fd, filp, on);
135 filp->f_flags |= FASYNC;
137 filp->f_flags &= ~FASYNC;
142 * When you add any new common ioctls to the switches above and below
143 * please update compat_sys_ioctl() too.
145 * do_vfs_ioctl() is not for drivers and not intended to be EXPORT_SYMBOL()'d.
146 * It's just a simple helper for sys_ioctl and compat_sys_ioctl.
148 int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
152 int __user *argp = (int __user *)arg;
156 set_close_on_exec(fd, 1);
160 set_close_on_exec(fd, 0);
164 /* BKL needed to avoid races tweaking f_flags */
166 error = ioctl_fionbio(filp, argp);
171 /* BKL needed to avoid races tweaking f_flags */
173 error = ioctl_fioasync(fd, filp, argp);
178 if (S_ISDIR(filp->f_path.dentry->d_inode->i_mode) ||
179 S_ISREG(filp->f_path.dentry->d_inode->i_mode) ||
180 S_ISLNK(filp->f_path.dentry->d_inode->i_mode)) {
182 inode_get_bytes(filp->f_path.dentry->d_inode);
183 error = copy_to_user((loff_t __user *)arg, &res,
184 sizeof(res)) ? -EFAULT : 0;
189 if (S_ISREG(filp->f_path.dentry->d_inode->i_mode))
190 error = file_ioctl(filp, cmd, arg);
192 error = vfs_ioctl(filp, cmd, arg);
198 SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
204 filp = fget_light(fd, &fput_needed);
208 error = security_file_ioctl(filp, cmd, arg);
212 error = do_vfs_ioctl(filp, fd, cmd, arg);
214 fput_light(filp, fput_needed);