mirror of
https://github.com/team-infusion-developers/android_kernel_samsung_msm8976.git
synced 2024-11-07 04:09:21 +00:00
73be192b17
It would be nice to know how often we get checksum failures. Even better, how many of them we can fix with the single bit ecc. So, we add a statistics structure. The structure can be installed into debugfs wherever the user wants. For ocfs2, we'll put it in the superblock-specific debugfs directory and pass it down from our higher-level functions. The stats are only registered with debugfs when the filesystem supports metadata ecc. Signed-off-by: Joel Becker <joel.becker@oracle.com>
107 lines
3.8 KiB
C
107 lines
3.8 KiB
C
/* -*- mode: c; c-basic-offset: 8; -*-
|
|
* vim: noexpandtab sw=8 ts=8 sts=0:
|
|
*
|
|
* blockcheck.h
|
|
*
|
|
* Checksum and ECC codes for the OCFS2 userspace library.
|
|
*
|
|
* Copyright (C) 2004, 2008 Oracle. All rights reserved.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public
|
|
* License, version 2, as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* General Public License for more details.
|
|
*/
|
|
|
|
#ifndef OCFS2_BLOCKCHECK_H
|
|
#define OCFS2_BLOCKCHECK_H
|
|
|
|
|
|
/* Count errors and error correction from blockcheck.c */
|
|
struct ocfs2_blockcheck_stats {
|
|
spinlock_t b_lock;
|
|
u64 b_check_count; /* Number of blocks we've checked */
|
|
u64 b_failure_count; /* Number of failed checksums */
|
|
u64 b_recover_count; /* Number of blocks fixed by ecc */
|
|
|
|
/*
|
|
* debugfs entries, used if this is passed to
|
|
* ocfs2_blockcheck_stats_debugfs_install()
|
|
*/
|
|
struct dentry *b_debug_dir; /* Parent of the debugfs files */
|
|
struct dentry *b_debug_check; /* Exposes b_check_count */
|
|
struct dentry *b_debug_failure; /* Exposes b_failure_count */
|
|
struct dentry *b_debug_recover; /* Exposes b_recover_count */
|
|
};
|
|
|
|
|
|
/* High level block API */
|
|
void ocfs2_compute_meta_ecc(struct super_block *sb, void *data,
|
|
struct ocfs2_block_check *bc);
|
|
int ocfs2_validate_meta_ecc(struct super_block *sb, void *data,
|
|
struct ocfs2_block_check *bc);
|
|
void ocfs2_compute_meta_ecc_bhs(struct super_block *sb,
|
|
struct buffer_head **bhs, int nr,
|
|
struct ocfs2_block_check *bc);
|
|
int ocfs2_validate_meta_ecc_bhs(struct super_block *sb,
|
|
struct buffer_head **bhs, int nr,
|
|
struct ocfs2_block_check *bc);
|
|
|
|
/* Lower level API */
|
|
void ocfs2_block_check_compute(void *data, size_t blocksize,
|
|
struct ocfs2_block_check *bc);
|
|
int ocfs2_block_check_validate(void *data, size_t blocksize,
|
|
struct ocfs2_block_check *bc,
|
|
struct ocfs2_blockcheck_stats *stats);
|
|
void ocfs2_block_check_compute_bhs(struct buffer_head **bhs, int nr,
|
|
struct ocfs2_block_check *bc);
|
|
int ocfs2_block_check_validate_bhs(struct buffer_head **bhs, int nr,
|
|
struct ocfs2_block_check *bc,
|
|
struct ocfs2_blockcheck_stats *stats);
|
|
|
|
/* Debug Initialization */
|
|
int ocfs2_blockcheck_stats_debugfs_install(struct ocfs2_blockcheck_stats *stats,
|
|
struct dentry *parent);
|
|
void ocfs2_blockcheck_stats_debugfs_remove(struct ocfs2_blockcheck_stats *stats);
|
|
|
|
/*
|
|
* Hamming code functions
|
|
*/
|
|
|
|
/*
|
|
* Encoding hamming code parity bits for a buffer.
|
|
*
|
|
* This is the low level encoder function. It can be called across
|
|
* multiple hunks just like the crc32 code. 'd' is the number of bits
|
|
* _in_this_hunk_. nr is the bit offset of this hunk. So, if you had
|
|
* two 512B buffers, you would do it like so:
|
|
*
|
|
* parity = ocfs2_hamming_encode(0, buf1, 512 * 8, 0);
|
|
* parity = ocfs2_hamming_encode(parity, buf2, 512 * 8, 512 * 8);
|
|
*
|
|
* If you just have one buffer, use ocfs2_hamming_encode_block().
|
|
*/
|
|
u32 ocfs2_hamming_encode(u32 parity, void *data, unsigned int d,
|
|
unsigned int nr);
|
|
/*
|
|
* Fix a buffer with a bit error. The 'fix' is the original parity
|
|
* xor'd with the parity calculated now.
|
|
*
|
|
* Like ocfs2_hamming_encode(), this can handle hunks. nr is the bit
|
|
* offset of the current hunk. If bit to be fixed is not part of the
|
|
* current hunk, this does nothing.
|
|
*
|
|
* If you only have one buffer, use ocfs2_hamming_fix_block().
|
|
*/
|
|
void ocfs2_hamming_fix(void *data, unsigned int d, unsigned int nr,
|
|
unsigned int fix);
|
|
|
|
/* Convenience wrappers for a single buffer of data */
|
|
extern u32 ocfs2_hamming_encode_block(void *data, unsigned int blocksize);
|
|
extern void ocfs2_hamming_fix_block(void *data, unsigned int blocksize,
|
|
unsigned int fix);
|
|
#endif
|