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
  27 struct 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
  44 int badblocks_check(struct badblocks *bb, sector_t s, int sectors,
  45                    sector_t *first_bad, int *bad_sectors);
  46 int badblocks_set(struct badblocks *bb, sector_t s, int sectors,
  47                         int acknowledged);
  48 int badblocks_clear(struct badblocks *bb, sector_t s, int sectors);
  49 void ack_all_badblocks(struct badblocks *bb);
  50 ssize_t badblocks_show(struct badblocks *bb, char *page, int unack);
  51 ssize_t badblocks_store(struct badblocks *bb, const char *page, size_t len,
  52                         int unack);
  53 int badblocks_init(struct badblocks *bb, int enable);
  54 void badblocks_exit(struct badblocks *bb);
  55 struct device;
  56 int devm_init_badblocks(struct device *dev, struct badblocks *bb);
  57 static 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