LXR linux/include/linux/badblocks.h

   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