include/linux/badblocks.h

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