From 2230dfe4ccc3add340dc6d437965b2de1d269fde Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Thu, 28 Jul 2011 11:31:46 +1000 Subject: md: beginnings of bad block management. This the first step in allowing md to track bad-blocks per-device so that we can fail individual blocks rather than the whole device. This patch just adds a data structure for recording bad blocks, with routines to add, remove, search the list. Signed-off-by: NeilBrown Reviewed-by: Namhyung Kim --- drivers/md/md.h | 48 +++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 47 insertions(+), 1 deletion(-) (limited to 'drivers/md/md.h') diff --git a/drivers/md/md.h b/drivers/md/md.h index 7d906a96477a..85af8433f8b8 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -29,6 +29,13 @@ typedef struct mddev_s mddev_t; typedef struct mdk_rdev_s mdk_rdev_t; +/* 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 MD_MAX_BADBLOCKS (PAGE_SIZE/8) + /* * MD's 'extended' device */ @@ -111,8 +118,47 @@ struct mdk_rdev_s struct sysfs_dirent *sysfs_state; /* handle for 'state' * sysfs entry */ + + struct badblocks { + int count; /* count of bad blocks */ + int shift; /* shift from sectors to block size + * a -ve shift means badblocks are + * disabled.*/ + u64 *page; /* badblock list */ + int changed; + seqlock_t lock; + } badblocks; }; +#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)) + +extern int md_is_badblock(struct badblocks *bb, sector_t s, int sectors, + sector_t *first_bad, int *bad_sectors); +static inline int is_badblock(mdk_rdev_t *rdev, sector_t s, int sectors, + sector_t *first_bad, int *bad_sectors) +{ + if (unlikely(rdev->badblocks.count)) { + int rv = md_is_badblock(&rdev->badblocks, rdev->data_offset + s, + sectors, + first_bad, bad_sectors); + if (rv) + *first_bad -= rdev->data_offset; + return rv; + } + return 0; +} +extern int rdev_set_badblocks(mdk_rdev_t *rdev, sector_t s, int sectors, + int acknowledged); +extern int rdev_clear_badblocks(mdk_rdev_t *rdev, sector_t s, int sectors); +extern void md_ack_all_badblocks(struct badblocks *bb); + struct mddev_s { void *private; @@ -517,7 +563,7 @@ extern void mddev_init(mddev_t *mddev); extern int md_run(mddev_t *mddev); extern void md_stop(mddev_t *mddev); extern void md_stop_writes(mddev_t *mddev); -extern void md_rdev_init(mdk_rdev_t *rdev); +extern int md_rdev_init(mdk_rdev_t *rdev); extern void mddev_suspend(mddev_t *mddev); extern void mddev_resume(mddev_t *mddev); -- cgit v1.2.3