1 /*
2  * Copyright (C) 2011 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "ext4_utils.h"
18 #include "wipe.h"
19 
20 #if WIPE_IS_SUPPORTED
21 
22 #if defined(__linux__)
23 
24 #include <linux/fs.h>
25 #include <sys/ioctl.h>
26 
27 #ifndef BLKDISCARD
28 #define BLKDISCARD _IO(0x12,119)
29 #endif
30 
31 #ifndef BLKSECDISCARD
32 #define BLKSECDISCARD _IO(0x12,125)
33 #endif
34 
wipe_block_device(int fd,s64 len)35 int wipe_block_device(int fd, s64 len)
36 {
37 	u64 range[2];
38 	int ret;
39 
40 	if (!is_block_device_fd(fd)) {
41 		// Wiping only makes sense on a block device.
42 		return 0;
43 	}
44 
45 	range[0] = 0;
46 	range[1] = len;
47 	ret = ioctl(fd, BLKSECDISCARD, &range);
48 	if (ret < 0) {
49 		range[0] = 0;
50 		range[1] = len;
51 		ret = ioctl(fd, BLKDISCARD, &range);
52 		if (ret < 0) {
53 			warn("Discard failed\n");
54 			return 1;
55 		} else {
56 			warn("Wipe via secure discard failed, used discard instead\n");
57 			return 0;
58 		}
59 	}
60 
61 	return 0;
62 }
63 
64 #else  /* __linux__ */
65 #error "Missing block device wiping implementation for this platform!"
66 #endif
67 
68 #else  /* WIPE_IS_SUPPORTED */
69 
wipe_block_device(int fd,s64 len)70 int wipe_block_device(int fd, s64 len)
71 {
72 	/* Wiping is not supported on this platform. */
73 	return 1;
74 }
75 
76 #endif  /* WIPE_IS_SUPPORTED */
77