1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/ext2/ioctl.c
4 *
5 * Copyright (C) 1993, 1994, 1995
6 * Remy Card (card@masi.ibp.fr)
7 * Laboratoire MASI - Institut Blaise Pascal
8 * Universite Pierre et Marie Curie (Paris VI)
9 */
10
11#include "ext2.h"
12#include <linux/capability.h>
13#include <linux/time.h>
14#include <linux/sched.h>
15#include <linux/compat.h>
16#include <linux/mount.h>
17#include <asm/current.h>
18#include <linux/uaccess.h>
19#include <linux/fileattr.h>
20
21int ext2_fileattr_get(struct dentry *dentry, struct fileattr *fa)
22{
23	struct ext2_inode_info *ei = EXT2_I(d_inode(dentry));
24
25	fileattr_fill_flags(fa, ei->i_flags & EXT2_FL_USER_VISIBLE);
26
27	return 0;
28}
29
30int ext2_fileattr_set(struct mnt_idmap *idmap,
31		      struct dentry *dentry, struct fileattr *fa)
32{
33	struct inode *inode = d_inode(dentry);
34	struct ext2_inode_info *ei = EXT2_I(inode);
35
36	if (fileattr_has_fsx(fa))
37		return -EOPNOTSUPP;
38
39	/* Is it quota file? Do not allow user to mess with it */
40	if (IS_NOQUOTA(inode))
41		return -EPERM;
42
43	ei->i_flags = (ei->i_flags & ~EXT2_FL_USER_MODIFIABLE) |
44		(fa->flags & EXT2_FL_USER_MODIFIABLE);
45
46	ext2_set_inode_flags(inode);
47	inode_set_ctime_current(inode);
48	mark_inode_dirty(inode);
49
50	return 0;
51}
52
53
54long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
55{
56	struct inode *inode = file_inode(filp);
57	struct ext2_inode_info *ei = EXT2_I(inode);
58	unsigned short rsv_window_size;
59	int ret;
60
61	ext2_debug ("cmd = %u, arg = %lu\n", cmd, arg);
62
63	switch (cmd) {
64	case EXT2_IOC_GETVERSION:
65		return put_user(inode->i_generation, (int __user *) arg);
66	case EXT2_IOC_SETVERSION: {
67		__u32 generation;
68
69		if (!inode_owner_or_capable(&nop_mnt_idmap, inode))
70			return -EPERM;
71		ret = mnt_want_write_file(filp);
72		if (ret)
73			return ret;
74		if (get_user(generation, (int __user *) arg)) {
75			ret = -EFAULT;
76			goto setversion_out;
77		}
78
79		inode_lock(inode);
80		inode_set_ctime_current(inode);
81		inode->i_generation = generation;
82		inode_unlock(inode);
83
84		mark_inode_dirty(inode);
85setversion_out:
86		mnt_drop_write_file(filp);
87		return ret;
88	}
89	case EXT2_IOC_GETRSVSZ:
90		if (test_opt(inode->i_sb, RESERVATION)
91			&& S_ISREG(inode->i_mode)
92			&& ei->i_block_alloc_info) {
93			rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
94			return put_user(rsv_window_size, (int __user *)arg);
95		}
96		return -ENOTTY;
97	case EXT2_IOC_SETRSVSZ: {
98
99		if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
100			return -ENOTTY;
101
102		if (!inode_owner_or_capable(&nop_mnt_idmap, inode))
103			return -EACCES;
104
105		if (get_user(rsv_window_size, (int __user *)arg))
106			return -EFAULT;
107
108		ret = mnt_want_write_file(filp);
109		if (ret)
110			return ret;
111
112		if (rsv_window_size > EXT2_MAX_RESERVE_BLOCKS)
113			rsv_window_size = EXT2_MAX_RESERVE_BLOCKS;
114
115		/*
116		 * need to allocate reservation structure for this inode
117		 * before set the window size
118		 */
119		/*
120		 * XXX What lock should protect the rsv_goal_size?
121		 * Accessed in ext2_get_block only.  ext3 uses i_truncate.
122		 */
123		mutex_lock(&ei->truncate_mutex);
124		if (!ei->i_block_alloc_info)
125			ext2_init_block_alloc_info(inode);
126
127		if (ei->i_block_alloc_info){
128			struct ext2_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
129			rsv->rsv_goal_size = rsv_window_size;
130		} else {
131			ret = -ENOMEM;
132		}
133
134		mutex_unlock(&ei->truncate_mutex);
135		mnt_drop_write_file(filp);
136		return ret;
137	}
138	default:
139		return -ENOTTY;
140	}
141}
142
143#ifdef CONFIG_COMPAT
144long ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
145{
146	/* These are just misnamed, they actually get/put from/to user an int */
147	switch (cmd) {
148	case EXT2_IOC32_GETVERSION:
149		cmd = EXT2_IOC_GETVERSION;
150		break;
151	case EXT2_IOC32_SETVERSION:
152		cmd = EXT2_IOC_SETVERSION;
153		break;
154	default:
155		return -ENOIOCTLCMD;
156	}
157	return ext2_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
158}
159#endif
160