From 9e0e252a048b0ba5066f0dc15c3b2468ffe5c422 Mon Sep 17 00:00:00 2001 From: Vishal Verma Date: Thu, 24 Dec 2015 19:20:32 -0700 Subject: badblocks: Add core badblock management code Take the core badblocks implementation from md, and make it generally available. This follows the same style as kernel implementations of linked lists, rb-trees etc, where you can have a structure that can be embedded anywhere, and accessor functions to manipulate the data. The only changes in this copy of the code are ones to generalize function/variable names from md-specific ones. Also add init and free functions. Signed-off-by: Vishal Verma Signed-off-by: Dan Williams --- include/linux/badblocks.h | 53 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) create mode 100644 include/linux/badblocks.h (limited to 'include/linux/badblocks.h') diff --git a/include/linux/badblocks.h b/include/linux/badblocks.h new file mode 100644 index 000000000000..929344630b51 --- /dev/null +++ b/include/linux/badblocks.h @@ -0,0 +1,53 @@ +#ifndef _LINUX_BADBLOCKS_H +#define _LINUX_BADBLOCKS_H + +#include +#include +#include +#include + +#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)) + +/* 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 MAX_BADBLOCKS (PAGE_SIZE/8) + +struct badblocks { + int count; /* count of bad blocks */ + int unacked_exist; /* there probably are unacknowledged + * bad blocks. This is only cleared + * when a read discovers none + */ + int shift; /* shift from sectors to block size + * a -ve shift means badblocks are + * disabled.*/ + u64 *page; /* badblock list */ + int changed; + seqlock_t lock; + sector_t sector; + sector_t size; /* in sectors */ +}; + +int badblocks_check(struct badblocks *bb, sector_t s, int sectors, + sector_t *first_bad, int *bad_sectors); +int badblocks_set(struct badblocks *bb, sector_t s, int sectors, + int acknowledged); +int badblocks_clear(struct badblocks *bb, sector_t s, int sectors); +void ack_all_badblocks(struct badblocks *bb); +ssize_t badblocks_show(struct badblocks *bb, char *page, int unack); +ssize_t badblocks_store(struct badblocks *bb, const char *page, size_t len, + int unack); +int badblocks_init(struct badblocks *bb, int enable); +void badblocks_free(struct badblocks *bb); + +#endif -- cgit v1.2.3