CasperSecurity
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_BADBLOCKS_H
#define _LINUX_BADBLOCKS_H
#include <linux/seqlock.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/stddef.h>
#include <linux/types.h>
#define BB_LEN_MASK (0x00000000000001FFULL)
#define BB_OFFSET_MASK (0x7FFFFFFFFFFFFE00ULL)
#define BB_ACK_MASK (0x8000000000000000ULL)
#define BB_MAX_LEN 512
#define BB_OFFSET(x) (((x) & BB_OFFSET_MASK) >> 9)
#define BB_LEN(x) (((x) & BB_LEN_MASK) + 1)
#define BB_ACK(x) (!!((x) & BB_ACK_MASK))
#define BB_MAKE(a, l, ack) (((a)<<9) | ((l)-1) | ((u64)(!!(ack)) << 63))
/* Bad block numbers are stored sorted in a single page.
* 64bits is used for each block or extent.
* 54 bits are sector number, 9 bits are extent size,
* 1 bit is an 'acknowledged' flag.
*/
#define MAX_BADBLOCKS (PAGE_SIZE/8)
struct badblocks {
struct device *dev; /* set by devm_init_badblocks */
int count; /* count of bad blocks */
int unacked_exist; /* there probably are unacknowledged
* bad blocks. This is only cleared
* when a read discovers none
*/
int shift; /* shift from sectors to block size
* a -ve shift means badblocks are
* disabled.*/
u64 *page; /* badblock list */
int changed;
seqlock_t lock;
sector_t sector;
sector_t size; /* in sectors */
};
int badblocks_check(struct badblocks *bb, sector_t s, int sectors,
sector_t *first_bad, int *bad_sectors);
int badblocks_set(struct badblocks *bb, sector_t s, int sectors,
int acknowledged);
int badblocks_clear(struct badblocks *bb, sector_t s, int sectors);
void ack_all_badblocks(struct badblocks *bb);
ssize_t badblocks_show(struct badblocks *bb, char *page, int unack);
ssize_t badblocks_store(struct badblocks *bb, const char *page, size_t len,
int unack);
int badblocks_init(struct badblocks *bb, int enable);
void badblocks_exit(struct badblocks *bb);
struct device;
int devm_init_badblocks(struct device *dev, struct badblocks *bb);
static inline void devm_exit_badblocks(struct device *dev, struct badblocks *bb)
{
if (bb->dev != dev) {
dev_WARN_ONCE(dev, 1, "%s: badblocks instance not associated\n",
__func__);
return;
}
badblocks_exit(bb);
}
#endif