include/linux/badblocks.h

   1 #ifndef _LINUX_BADBLOCKS_H
   2 #define _LINUX_BADBLOCKS_H
   3
   4 #include <linux/seqlock.h>
   5 #include <linux/kernel.h>
   6 #include <linux/stddef.h>
   7 #include <linux/types.h>
   8
   9 #define BB_LEN_MASK     (0x00000000000001FFULL)
  10 #define BB_OFFSET_MASK  (0x7FFFFFFFFFFFFE00ULL)
  11 #define BB_ACK_MASK     (0x8000000000000000ULL)
  12 #define BB_MAX_LEN      512
  13 #define BB_OFFSET(x)    (((x) & BB_OFFSET_MASK) >> 9)
  14 #define BB_LEN(x)       (((x) & BB_LEN_MASK) + 1)
  15 #define BB_ACK(x)       (!!((x) & BB_ACK_MASK))
  16 #define BB_MAKE(a, l, ack) (((a)<<9) | ((l)-1) | ((u64)(!!(ack)) << 63))
  17
  18 /* Bad block numbers are stored sorted in a single page.
  19  * 64bits is used for each block or extent.
  20  * 54 bits are sector number, 9 bits are extent size,
  21  * 1 bit is an 'acknowledged' flag.
  22  */
  23 #define MAX_BADBLOCKS   (PAGE_SIZE/8)
  24
  25 struct badblocks {
  26         int count;              /* count of bad blocks */
  27         int unacked_exist;      /* there probably are unacknowledged
  28                                  * bad blocks.  This is only cleared
  29                                  * when a read discovers none
  30                                  */
  31         int shift;              /* shift from sectors to block size
  32                                  * a -ve shift means badblocks are
  33                                  * disabled.*/
  34         u64 *page;              /* badblock list */
  35         int changed;
  36         seqlock_t lock;
  37         sector_t sector;
  38         sector_t size;          /* in sectors */
  39 };
  40
  41 int badblocks_check(struct badblocks *bb, sector_t s, int sectors,
  42                    sector_t *first_bad, int *bad_sectors);
  43 int badblocks_set(struct badblocks *bb, sector_t s, int sectors,
  44                         int acknowledged);
  45 int badblocks_clear(struct badblocks *bb, sector_t s, int sectors);
  46 void ack_all_badblocks(struct badblocks *bb);
  47 ssize_t badblocks_show(struct badblocks *bb, char *page, int unack);
  48 ssize_t badblocks_store(struct badblocks *bb, const char *page, size_t len,
  49                         int unack);
  50 int badblocks_init(struct badblocks *bb, int enable);
  51 void badblocks_free(struct badblocks *bb);
  52
  53 #endif