1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_BADBLOCKS_H
3#define _LINUX_BADBLOCKS_H
4
5#include <linux/seqlock.h>
6#include <linux/device.h>
7#include <linux/kernel.h>
8#include <linux/stddef.h>
9#include <linux/types.h>
10
11#define BB_LEN_MASK (0x00000000000001FFULL)
12#define BB_OFFSET_MASK (0x7FFFFFFFFFFFFE00ULL)
13#define BB_ACK_MASK (0x8000000000000000ULL)
14#define BB_MAX_LEN 512
15#define BB_OFFSET(x) (((x) & BB_OFFSET_MASK) >> 9)
16#define BB_LEN(x) (((x) & BB_LEN_MASK) + 1)
17#define BB_ACK(x) (!!((x) & BB_ACK_MASK))
18#define BB_MAKE(a, l, ack) (((a)<<9) | ((l)-1) | ((u64)(!!(ack)) << 63))
19
20/* Bad block numbers are stored sorted in a single page.
21 * 64bits is used for each block or extent.
22 * 54 bits are sector number, 9 bits are extent size,
23 * 1 bit is an 'acknowledged' flag.
24 */
25#define MAX_BADBLOCKS (PAGE_SIZE/8)
26
27struct badblocks {
28 struct device *dev; /* set by devm_init_badblocks */
29 int count; /* count of bad blocks */
30 int unacked_exist; /* there probably are unacknowledged
31 * bad blocks. This is only cleared
32 * when a read discovers none
33 */
34 int shift; /* shift from sectors to block size
35 * a -ve shift means badblocks are
36 * disabled.*/
37 u64 *page; /* badblock list */
38 int changed;
39 seqlock_t lock;
40 sector_t sector;
41 sector_t size; /* in sectors */
42};
43
44int badblocks_check(struct badblocks *bb, sector_t s, int sectors,
45 sector_t *first_bad, int *bad_sectors);
46int badblocks_set(struct badblocks *bb, sector_t s, int sectors,
47 int acknowledged);
48int badblocks_clear(struct badblocks *bb, sector_t s, int sectors);
49void ack_all_badblocks(struct badblocks *bb);
50ssize_t badblocks_show(struct badblocks *bb, char *page, int unack);
51ssize_t badblocks_store(struct badblocks *bb, const char *page, size_t len,
52 int unack);
53int badblocks_init(struct badblocks *bb, int enable);
54void badblocks_exit(struct badblocks *bb);
55struct device;
56int devm_init_badblocks(struct device *dev, struct badblocks *bb);
57static inline void devm_exit_badblocks(struct device *dev, struct badblocks *bb)
58{
59 if (bb->dev != dev) {
60 dev_WARN_ONCE(dev, 1, "%s: badblocks instance not associated\n",
61 __func__);
62 return;
63 }
64 badblocks_exit(bb);
65}
66#endif
67