xref: /openbmc/linux/fs/jfs/ioctl.c (revision e6dec923)
1 /*
2  * linux/fs/jfs/ioctl.c
3  *
4  * Copyright (C) 2006 Herbert Poetzl
5  * adapted from Remy Card's ext2/ioctl.c
6  */
7 
8 #include <linux/fs.h>
9 #include <linux/ctype.h>
10 #include <linux/capability.h>
11 #include <linux/mount.h>
12 #include <linux/time.h>
13 #include <linux/sched.h>
14 #include <linux/blkdev.h>
15 #include <asm/current.h>
16 #include <linux/uaccess.h>
17 
18 #include "jfs_filsys.h"
19 #include "jfs_debug.h"
20 #include "jfs_incore.h"
21 #include "jfs_dinode.h"
22 #include "jfs_inode.h"
23 #include "jfs_dmap.h"
24 #include "jfs_discard.h"
25 
26 static struct {
27 	long jfs_flag;
28 	long ext2_flag;
29 } jfs_map[] = {
30 	{JFS_NOATIME_FL,	FS_NOATIME_FL},
31 	{JFS_DIRSYNC_FL,	FS_DIRSYNC_FL},
32 	{JFS_SYNC_FL,		FS_SYNC_FL},
33 	{JFS_SECRM_FL,		FS_SECRM_FL},
34 	{JFS_UNRM_FL,		FS_UNRM_FL},
35 	{JFS_APPEND_FL,		FS_APPEND_FL},
36 	{JFS_IMMUTABLE_FL,	FS_IMMUTABLE_FL},
37 	{0, 0},
38 };
39 
40 static long jfs_map_ext2(unsigned long flags, int from)
41 {
42 	int index=0;
43 	long mapped=0;
44 
45 	while (jfs_map[index].jfs_flag) {
46 		if (from) {
47 			if (jfs_map[index].ext2_flag & flags)
48 				mapped |= jfs_map[index].jfs_flag;
49 		} else {
50 			if (jfs_map[index].jfs_flag & flags)
51 				mapped |= jfs_map[index].ext2_flag;
52 		}
53 		index++;
54 	}
55 	return mapped;
56 }
57 
58 
59 long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
60 {
61 	struct inode *inode = file_inode(filp);
62 	struct jfs_inode_info *jfs_inode = JFS_IP(inode);
63 	unsigned int flags;
64 
65 	switch (cmd) {
66 	case JFS_IOC_GETFLAGS:
67 		flags = jfs_inode->mode2 & JFS_FL_USER_VISIBLE;
68 		flags = jfs_map_ext2(flags, 0);
69 		return put_user(flags, (int __user *) arg);
70 	case JFS_IOC_SETFLAGS: {
71 		unsigned int oldflags;
72 		int err;
73 
74 		err = mnt_want_write_file(filp);
75 		if (err)
76 			return err;
77 
78 		if (!inode_owner_or_capable(inode)) {
79 			err = -EACCES;
80 			goto setflags_out;
81 		}
82 		if (get_user(flags, (int __user *) arg)) {
83 			err = -EFAULT;
84 			goto setflags_out;
85 		}
86 
87 		flags = jfs_map_ext2(flags, 1);
88 		if (!S_ISDIR(inode->i_mode))
89 			flags &= ~JFS_DIRSYNC_FL;
90 
91 		/* Is it quota file? Do not allow user to mess with it */
92 		if (IS_NOQUOTA(inode)) {
93 			err = -EPERM;
94 			goto setflags_out;
95 		}
96 
97 		/* Lock against other parallel changes of flags */
98 		inode_lock(inode);
99 
100 		oldflags = jfs_inode->mode2;
101 
102 		/*
103 		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
104 		 * the relevant capability.
105 		 */
106 		if ((oldflags & JFS_IMMUTABLE_FL) ||
107 			((flags ^ oldflags) &
108 			(JFS_APPEND_FL | JFS_IMMUTABLE_FL))) {
109 			if (!capable(CAP_LINUX_IMMUTABLE)) {
110 				inode_unlock(inode);
111 				err = -EPERM;
112 				goto setflags_out;
113 			}
114 		}
115 
116 		flags = flags & JFS_FL_USER_MODIFIABLE;
117 		flags |= oldflags & ~JFS_FL_USER_MODIFIABLE;
118 		jfs_inode->mode2 = flags;
119 
120 		jfs_set_inode_flags(inode);
121 		inode_unlock(inode);
122 		inode->i_ctime = current_time(inode);
123 		mark_inode_dirty(inode);
124 setflags_out:
125 		mnt_drop_write_file(filp);
126 		return err;
127 	}
128 
129 	case FITRIM:
130 	{
131 		struct super_block *sb = inode->i_sb;
132 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
133 		struct fstrim_range range;
134 		s64 ret = 0;
135 
136 		if (!capable(CAP_SYS_ADMIN))
137 			return -EPERM;
138 
139 		if (!blk_queue_discard(q)) {
140 			jfs_warn("FITRIM not supported on device");
141 			return -EOPNOTSUPP;
142 		}
143 
144 		if (copy_from_user(&range, (struct fstrim_range __user *)arg,
145 		    sizeof(range)))
146 			return -EFAULT;
147 
148 		range.minlen = max_t(unsigned int, range.minlen,
149 			q->limits.discard_granularity);
150 
151 		ret = jfs_ioc_trim(inode, &range);
152 		if (ret < 0)
153 			return ret;
154 
155 		if (copy_to_user((struct fstrim_range __user *)arg, &range,
156 		    sizeof(range)))
157 			return -EFAULT;
158 
159 		return 0;
160 	}
161 
162 	default:
163 		return -ENOTTY;
164 	}
165 }
166 
167 #ifdef CONFIG_COMPAT
168 long jfs_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
169 {
170 	/* While these ioctl numbers defined with 'long' and have different
171 	 * numbers than the 64bit ABI,
172 	 * the actual implementation only deals with ints and is compatible.
173 	 */
174 	switch (cmd) {
175 	case JFS_IOC_GETFLAGS32:
176 		cmd = JFS_IOC_GETFLAGS;
177 		break;
178 	case JFS_IOC_SETFLAGS32:
179 		cmd = JFS_IOC_SETFLAGS;
180 		break;
181 	}
182 	return jfs_ioctl(filp, cmd, arg);
183 }
184 #endif
185