xref: /openbmc/linux/fs/jfs/ioctl.c (revision c819e2cf)
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 <asm/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 		jfs_get_inode_flags(jfs_inode);
68 		flags = jfs_inode->mode2 & JFS_FL_USER_VISIBLE;
69 		flags = jfs_map_ext2(flags, 0);
70 		return put_user(flags, (int __user *) arg);
71 	case JFS_IOC_SETFLAGS: {
72 		unsigned int oldflags;
73 		int err;
74 
75 		err = mnt_want_write_file(filp);
76 		if (err)
77 			return err;
78 
79 		if (!inode_owner_or_capable(inode)) {
80 			err = -EACCES;
81 			goto setflags_out;
82 		}
83 		if (get_user(flags, (int __user *) arg)) {
84 			err = -EFAULT;
85 			goto setflags_out;
86 		}
87 
88 		flags = jfs_map_ext2(flags, 1);
89 		if (!S_ISDIR(inode->i_mode))
90 			flags &= ~JFS_DIRSYNC_FL;
91 
92 		/* Is it quota file? Do not allow user to mess with it */
93 		if (IS_NOQUOTA(inode)) {
94 			err = -EPERM;
95 			goto setflags_out;
96 		}
97 
98 		/* Lock against other parallel changes of flags */
99 		mutex_lock(&inode->i_mutex);
100 
101 		jfs_get_inode_flags(jfs_inode);
102 		oldflags = jfs_inode->mode2;
103 
104 		/*
105 		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
106 		 * the relevant capability.
107 		 */
108 		if ((oldflags & JFS_IMMUTABLE_FL) ||
109 			((flags ^ oldflags) &
110 			(JFS_APPEND_FL | JFS_IMMUTABLE_FL))) {
111 			if (!capable(CAP_LINUX_IMMUTABLE)) {
112 				mutex_unlock(&inode->i_mutex);
113 				err = -EPERM;
114 				goto setflags_out;
115 			}
116 		}
117 
118 		flags = flags & JFS_FL_USER_MODIFIABLE;
119 		flags |= oldflags & ~JFS_FL_USER_MODIFIABLE;
120 		jfs_inode->mode2 = flags;
121 
122 		jfs_set_inode_flags(inode);
123 		mutex_unlock(&inode->i_mutex);
124 		inode->i_ctime = CURRENT_TIME_SEC;
125 		mark_inode_dirty(inode);
126 setflags_out:
127 		mnt_drop_write_file(filp);
128 		return err;
129 	}
130 
131 	case FITRIM:
132 	{
133 		struct super_block *sb = inode->i_sb;
134 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
135 		struct fstrim_range range;
136 		s64 ret = 0;
137 
138 		if (!capable(CAP_SYS_ADMIN))
139 			return -EPERM;
140 
141 		if (!blk_queue_discard(q)) {
142 			jfs_warn("FITRIM not supported on device");
143 			return -EOPNOTSUPP;
144 		}
145 
146 		if (copy_from_user(&range, (struct fstrim_range __user *)arg,
147 		    sizeof(range)))
148 			return -EFAULT;
149 
150 		range.minlen = max_t(unsigned int, range.minlen,
151 			q->limits.discard_granularity);
152 
153 		ret = jfs_ioc_trim(inode, &range);
154 		if (ret < 0)
155 			return ret;
156 
157 		if (copy_to_user((struct fstrim_range __user *)arg, &range,
158 		    sizeof(range)))
159 			return -EFAULT;
160 
161 		return 0;
162 	}
163 
164 	default:
165 		return -ENOTTY;
166 	}
167 }
168 
169 #ifdef CONFIG_COMPAT
170 long jfs_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
171 {
172 	/* While these ioctl numbers defined with 'long' and have different
173 	 * numbers than the 64bit ABI,
174 	 * the actual implementation only deals with ints and is compatible.
175 	 */
176 	switch (cmd) {
177 	case JFS_IOC_GETFLAGS32:
178 		cmd = JFS_IOC_GETFLAGS;
179 		break;
180 	case JFS_IOC_SETFLAGS32:
181 		cmd = JFS_IOC_SETFLAGS;
182 		break;
183 	case FITRIM:
184 		cmd = FITRIM;
185 		break;
186 	}
187 	return jfs_ioctl(filp, cmd, arg);
188 }
189 #endif
190