648 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			648 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* -*- mode: c; c-basic-offset: 8; -*-
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|  * vim: noexpandtab sw=8 ts=8 sts=0:
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|  *
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|  * blockcheck.c
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|  *
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|  * Checksum and ECC codes for the OCFS2 userspace library.
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|  *
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|  * Copyright (C) 2006, 2008 Oracle.  All rights reserved.
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|  *
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|  * This program is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU General Public
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|  * License, version 2, as published by the Free Software Foundation.
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|  *
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|  * This program is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * General Public License for more details.
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|  */
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| 
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| #include <linux/kernel.h>
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| #include <linux/types.h>
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| #include <linux/crc32.h>
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| #include <linux/buffer_head.h>
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| #include <linux/bitops.h>
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| #include <linux/debugfs.h>
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| #include <linux/module.h>
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| #include <linux/fs.h>
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| #include <asm/byteorder.h>
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| 
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| #include <cluster/masklog.h>
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| 
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| #include "ocfs2.h"
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| 
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| #include "blockcheck.h"
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| 
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| 
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| /*
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|  * We use the following conventions:
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|  *
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|  * d = # data bits
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|  * p = # parity bits
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|  * c = # total code bits (d + p)
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|  */
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| 
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| 
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| /*
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|  * Calculate the bit offset in the hamming code buffer based on the bit's
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|  * offset in the data buffer.  Since the hamming code reserves all
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|  * power-of-two bits for parity, the data bit number and the code bit
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|  * number are offset by all the parity bits beforehand.
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|  *
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|  * Recall that bit numbers in hamming code are 1-based.  This function
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|  * takes the 0-based data bit from the caller.
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|  *
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|  * An example.  Take bit 1 of the data buffer.  1 is a power of two (2^0),
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|  * so it's a parity bit.  2 is a power of two (2^1), so it's a parity bit.
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|  * 3 is not a power of two.  So bit 1 of the data buffer ends up as bit 3
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|  * in the code buffer.
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|  *
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|  * The caller can pass in *p if it wants to keep track of the most recent
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|  * number of parity bits added.  This allows the function to start the
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|  * calculation at the last place.
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|  */
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| static unsigned int calc_code_bit(unsigned int i, unsigned int *p_cache)
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| {
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| 	unsigned int b, p = 0;
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| 
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| 	/*
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| 	 * Data bits are 0-based, but we're talking code bits, which
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| 	 * are 1-based.
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| 	 */
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| 	b = i + 1;
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| 
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| 	/* Use the cache if it is there */
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| 	if (p_cache)
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| 		p = *p_cache;
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|         b += p;
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| 
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| 	/*
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| 	 * For every power of two below our bit number, bump our bit.
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| 	 *
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| 	 * We compare with (b + 1) because we have to compare with what b
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| 	 * would be _if_ it were bumped up by the parity bit.  Capice?
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| 	 *
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| 	 * p is set above.
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| 	 */
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| 	for (; (1 << p) < (b + 1); p++)
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| 		b++;
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| 
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| 	if (p_cache)
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| 		*p_cache = p;
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| 
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| 	return b;
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| }
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| 
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| /*
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|  * This is the low level encoder function.  It can be called across
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|  * multiple hunks just like the crc32 code.  'd' is the number of bits
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|  * _in_this_hunk_.  nr is the bit offset of this hunk.  So, if you had
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|  * two 512B buffers, you would do it like so:
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|  *
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|  * parity = ocfs2_hamming_encode(0, buf1, 512 * 8, 0);
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|  * parity = ocfs2_hamming_encode(parity, buf2, 512 * 8, 512 * 8);
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|  *
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|  * If you just have one buffer, use ocfs2_hamming_encode_block().
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|  */
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| u32 ocfs2_hamming_encode(u32 parity, void *data, unsigned int d, unsigned int nr)
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| {
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| 	unsigned int i, b, p = 0;
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| 
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| 	BUG_ON(!d);
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| 
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| 	/*
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| 	 * b is the hamming code bit number.  Hamming code specifies a
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| 	 * 1-based array, but C uses 0-based.  So 'i' is for C, and 'b' is
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| 	 * for the algorithm.
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| 	 *
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| 	 * The i++ in the for loop is so that the start offset passed
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| 	 * to ocfs2_find_next_bit_set() is one greater than the previously
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| 	 * found bit.
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| 	 */
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| 	for (i = 0; (i = ocfs2_find_next_bit(data, d, i)) < d; i++)
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| 	{
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| 		/*
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| 		 * i is the offset in this hunk, nr + i is the total bit
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| 		 * offset.
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| 		 */
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| 		b = calc_code_bit(nr + i, &p);
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| 
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| 		/*
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| 		 * Data bits in the resultant code are checked by
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| 		 * parity bits that are part of the bit number
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| 		 * representation.  Huh?
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| 		 *
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| 		 * <wikipedia href="http://en.wikipedia.org/wiki/Hamming_code">
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| 		 * In other words, the parity bit at position 2^k
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| 		 * checks bits in positions having bit k set in
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| 		 * their binary representation.  Conversely, for
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| 		 * instance, bit 13, i.e. 1101(2), is checked by
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| 		 * bits 1000(2) = 8, 0100(2)=4 and 0001(2) = 1.
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| 		 * </wikipedia>
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| 		 *
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| 		 * Note that 'k' is the _code_ bit number.  'b' in
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| 		 * our loop.
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| 		 */
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| 		parity ^= b;
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| 	}
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| 
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| 	/* While the data buffer was treated as little endian, the
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| 	 * return value is in host endian. */
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| 	return parity;
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| }
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| 
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| u32 ocfs2_hamming_encode_block(void *data, unsigned int blocksize)
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| {
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| 	return ocfs2_hamming_encode(0, data, blocksize * 8, 0);
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| }
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| 
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| /*
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|  * Like ocfs2_hamming_encode(), this can handle hunks.  nr is the bit
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|  * offset of the current hunk.  If bit to be fixed is not part of the
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|  * current hunk, this does nothing.
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|  *
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|  * If you only have one hunk, use ocfs2_hamming_fix_block().
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|  */
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| void ocfs2_hamming_fix(void *data, unsigned int d, unsigned int nr,
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| 		       unsigned int fix)
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| {
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| 	unsigned int i, b;
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| 
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| 	BUG_ON(!d);
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| 
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| 	/*
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| 	 * If the bit to fix has an hweight of 1, it's a parity bit.  One
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| 	 * busted parity bit is its own error.  Nothing to do here.
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| 	 */
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| 	if (hweight32(fix) == 1)
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| 		return;
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| 
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| 	/*
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| 	 * nr + d is the bit right past the data hunk we're looking at.
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| 	 * If fix after that, nothing to do
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| 	 */
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| 	if (fix >= calc_code_bit(nr + d, NULL))
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| 		return;
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| 
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| 	/*
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| 	 * nr is the offset in the data hunk we're starting at.  Let's
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| 	 * start b at the offset in the code buffer.  See hamming_encode()
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| 	 * for a more detailed description of 'b'.
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| 	 */
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| 	b = calc_code_bit(nr, NULL);
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| 	/* If the fix is before this hunk, nothing to do */
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| 	if (fix < b)
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| 		return;
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| 
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| 	for (i = 0; i < d; i++, b++)
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| 	{
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| 		/* Skip past parity bits */
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| 		while (hweight32(b) == 1)
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| 			b++;
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| 
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| 		/*
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| 		 * i is the offset in this data hunk.
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| 		 * nr + i is the offset in the total data buffer.
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| 		 * b is the offset in the total code buffer.
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| 		 *
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| 		 * Thus, when b == fix, bit i in the current hunk needs
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| 		 * fixing.
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| 		 */
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| 		if (b == fix)
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| 		{
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| 			if (ocfs2_test_bit(i, data))
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| 				ocfs2_clear_bit(i, data);
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| 			else
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| 				ocfs2_set_bit(i, data);
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| 			break;
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| 		}
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| 	}
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| }
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| 
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| void ocfs2_hamming_fix_block(void *data, unsigned int blocksize,
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| 			     unsigned int fix)
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| {
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| 	ocfs2_hamming_fix(data, blocksize * 8, 0, fix);
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| }
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| 
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| 
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| /*
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|  * Debugfs handling.
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|  */
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| 
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| #ifdef CONFIG_DEBUG_FS
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| 
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| static int blockcheck_u64_get(void *data, u64 *val)
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| {
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| 	*val = *(u64 *)data;
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| 	return 0;
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| }
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| DEFINE_SIMPLE_ATTRIBUTE(blockcheck_fops, blockcheck_u64_get, NULL, "%llu\n");
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| 
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| static struct dentry *blockcheck_debugfs_create(const char *name,
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| 						struct dentry *parent,
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| 						u64 *value)
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| {
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| 	return debugfs_create_file(name, S_IFREG | S_IRUSR, parent, value,
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| 				   &blockcheck_fops);
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| }
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| 
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| static void ocfs2_blockcheck_debug_remove(struct ocfs2_blockcheck_stats *stats)
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| {
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| 	if (stats) {
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| 		debugfs_remove(stats->b_debug_check);
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| 		stats->b_debug_check = NULL;
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| 		debugfs_remove(stats->b_debug_failure);
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| 		stats->b_debug_failure = NULL;
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| 		debugfs_remove(stats->b_debug_recover);
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| 		stats->b_debug_recover = NULL;
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| 		debugfs_remove(stats->b_debug_dir);
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| 		stats->b_debug_dir = NULL;
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| 	}
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| }
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| 
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| static int ocfs2_blockcheck_debug_install(struct ocfs2_blockcheck_stats *stats,
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| 					  struct dentry *parent)
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| {
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| 	int rc = -EINVAL;
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| 
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| 	if (!stats)
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| 		goto out;
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| 
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| 	stats->b_debug_dir = debugfs_create_dir("blockcheck", parent);
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| 	if (!stats->b_debug_dir)
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| 		goto out;
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| 
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| 	stats->b_debug_check =
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| 		blockcheck_debugfs_create("blocks_checked",
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| 					  stats->b_debug_dir,
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| 					  &stats->b_check_count);
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| 
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| 	stats->b_debug_failure =
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| 		blockcheck_debugfs_create("checksums_failed",
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| 					  stats->b_debug_dir,
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| 					  &stats->b_failure_count);
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| 
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| 	stats->b_debug_recover =
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| 		blockcheck_debugfs_create("ecc_recoveries",
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| 					  stats->b_debug_dir,
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| 					  &stats->b_recover_count);
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| 	if (stats->b_debug_check && stats->b_debug_failure &&
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| 	    stats->b_debug_recover)
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| 		rc = 0;
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| 
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| out:
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| 	if (rc)
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| 		ocfs2_blockcheck_debug_remove(stats);
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| 	return rc;
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| }
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| #else
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| static inline int ocfs2_blockcheck_debug_install(struct ocfs2_blockcheck_stats *stats,
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| 						 struct dentry *parent)
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| {
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| 	return 0;
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| }
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| 
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| static inline void ocfs2_blockcheck_debug_remove(struct ocfs2_blockcheck_stats *stats)
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| {
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| }
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| #endif  /* CONFIG_DEBUG_FS */
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| 
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| /* Always-called wrappers for starting and stopping the debugfs files */
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| int ocfs2_blockcheck_stats_debugfs_install(struct ocfs2_blockcheck_stats *stats,
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| 					   struct dentry *parent)
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| {
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| 	return ocfs2_blockcheck_debug_install(stats, parent);
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| }
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| 
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| void ocfs2_blockcheck_stats_debugfs_remove(struct ocfs2_blockcheck_stats *stats)
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| {
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| 	ocfs2_blockcheck_debug_remove(stats);
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| }
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| 
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| static void ocfs2_blockcheck_inc_check(struct ocfs2_blockcheck_stats *stats)
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| {
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| 	u64 new_count;
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| 
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| 	if (!stats)
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| 		return;
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| 
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| 	spin_lock(&stats->b_lock);
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| 	stats->b_check_count++;
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| 	new_count = stats->b_check_count;
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| 	spin_unlock(&stats->b_lock);
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| 
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| 	if (!new_count)
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| 		mlog(ML_NOTICE, "Block check count has wrapped\n");
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| }
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| 
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| static void ocfs2_blockcheck_inc_failure(struct ocfs2_blockcheck_stats *stats)
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| {
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| 	u64 new_count;
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| 
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| 	if (!stats)
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| 		return;
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| 
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| 	spin_lock(&stats->b_lock);
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| 	stats->b_failure_count++;
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| 	new_count = stats->b_failure_count;
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| 	spin_unlock(&stats->b_lock);
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| 
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| 	if (!new_count)
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| 		mlog(ML_NOTICE, "Checksum failure count has wrapped\n");
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| }
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| 
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| static void ocfs2_blockcheck_inc_recover(struct ocfs2_blockcheck_stats *stats)
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| {
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| 	u64 new_count;
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| 
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| 	if (!stats)
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| 		return;
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| 
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| 	spin_lock(&stats->b_lock);
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| 	stats->b_recover_count++;
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| 	new_count = stats->b_recover_count;
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| 	spin_unlock(&stats->b_lock);
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| 
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| 	if (!new_count)
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| 		mlog(ML_NOTICE, "ECC recovery count has wrapped\n");
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| }
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| 
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| 
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| 
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| /*
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|  * These are the low-level APIs for using the ocfs2_block_check structure.
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|  */
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| 
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| /*
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|  * This function generates check information for a block.
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|  * data is the block to be checked.  bc is a pointer to the
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|  * ocfs2_block_check structure describing the crc32 and the ecc.
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|  *
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|  * bc should be a pointer inside data, as the function will
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|  * take care of zeroing it before calculating the check information.  If
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|  * bc does not point inside data, the caller must make sure any inline
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|  * ocfs2_block_check structures are zeroed.
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|  *
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|  * The data buffer must be in on-disk endian (little endian for ocfs2).
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|  * bc will be filled with little-endian values and will be ready to go to
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|  * disk.
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|  */
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| void ocfs2_block_check_compute(void *data, size_t blocksize,
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| 			       struct ocfs2_block_check *bc)
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| {
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| 	u32 crc;
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| 	u32 ecc;
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| 
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| 	memset(bc, 0, sizeof(struct ocfs2_block_check));
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| 
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| 	crc = crc32_le(~0, data, blocksize);
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| 	ecc = ocfs2_hamming_encode_block(data, blocksize);
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| 
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| 	/*
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| 	 * No ecc'd ocfs2 structure is larger than 4K, so ecc will be no
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| 	 * larger than 16 bits.
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| 	 */
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| 	BUG_ON(ecc > USHRT_MAX);
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| 
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| 	bc->bc_crc32e = cpu_to_le32(crc);
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| 	bc->bc_ecc = cpu_to_le16((u16)ecc);
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| }
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| 
 | |
| /*
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|  * This function validates existing check information.  Like _compute,
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|  * the function will take care of zeroing bc before calculating check codes.
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|  * If bc is not a pointer inside data, the caller must have zeroed any
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|  * inline ocfs2_block_check structures.
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|  *
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|  * Again, the data passed in should be the on-disk endian.
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|  */
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| int ocfs2_block_check_validate(void *data, size_t blocksize,
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| 			       struct ocfs2_block_check *bc,
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| 			       struct ocfs2_blockcheck_stats *stats)
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| {
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| 	int rc = 0;
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| 	u32 bc_crc32e;
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| 	u16 bc_ecc;
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| 	u32 crc, ecc;
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| 
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| 	ocfs2_blockcheck_inc_check(stats);
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| 
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| 	bc_crc32e = le32_to_cpu(bc->bc_crc32e);
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| 	bc_ecc = le16_to_cpu(bc->bc_ecc);
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| 
 | |
| 	memset(bc, 0, sizeof(struct ocfs2_block_check));
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| 
 | |
| 	/* Fast path - if the crc32 validates, we're good to go */
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| 	crc = crc32_le(~0, data, blocksize);
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| 	if (crc == bc_crc32e)
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| 		goto out;
 | |
| 
 | |
| 	ocfs2_blockcheck_inc_failure(stats);
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| 	mlog(ML_ERROR,
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| 	     "CRC32 failed: stored: 0x%x, computed 0x%x. Applying ECC.\n",
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| 	     (unsigned int)bc_crc32e, (unsigned int)crc);
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| 
 | |
| 	/* Ok, try ECC fixups */
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| 	ecc = ocfs2_hamming_encode_block(data, blocksize);
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| 	ocfs2_hamming_fix_block(data, blocksize, ecc ^ bc_ecc);
 | |
| 
 | |
| 	/* And check the crc32 again */
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| 	crc = crc32_le(~0, data, blocksize);
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| 	if (crc == bc_crc32e) {
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| 		ocfs2_blockcheck_inc_recover(stats);
 | |
| 		goto out;
 | |
| 	}
 | |
| 
 | |
| 	mlog(ML_ERROR, "Fixed CRC32 failed: stored: 0x%x, computed 0x%x\n",
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| 	     (unsigned int)bc_crc32e, (unsigned int)crc);
 | |
| 
 | |
| 	rc = -EIO;
 | |
| 
 | |
| out:
 | |
| 	bc->bc_crc32e = cpu_to_le32(bc_crc32e);
 | |
| 	bc->bc_ecc = cpu_to_le16(bc_ecc);
 | |
| 
 | |
| 	return rc;
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| }
 | |
| 
 | |
| /*
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|  * This function generates check information for a list of buffer_heads.
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|  * bhs is the blocks to be checked.  bc is a pointer to the
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|  * ocfs2_block_check structure describing the crc32 and the ecc.
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|  *
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|  * bc should be a pointer inside data, as the function will
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|  * take care of zeroing it before calculating the check information.  If
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|  * bc does not point inside data, the caller must make sure any inline
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|  * ocfs2_block_check structures are zeroed.
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|  *
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|  * The data buffer must be in on-disk endian (little endian for ocfs2).
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|  * bc will be filled with little-endian values and will be ready to go to
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|  * disk.
 | |
|  */
 | |
| void ocfs2_block_check_compute_bhs(struct buffer_head **bhs, int nr,
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| 				   struct ocfs2_block_check *bc)
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| {
 | |
| 	int i;
 | |
| 	u32 crc, ecc;
 | |
| 
 | |
| 	BUG_ON(nr < 0);
 | |
| 
 | |
| 	if (!nr)
 | |
| 		return;
 | |
| 
 | |
| 	memset(bc, 0, sizeof(struct ocfs2_block_check));
 | |
| 
 | |
| 	for (i = 0, crc = ~0, ecc = 0; i < nr; i++) {
 | |
| 		crc = crc32_le(crc, bhs[i]->b_data, bhs[i]->b_size);
 | |
| 		/*
 | |
| 		 * The number of bits in a buffer is obviously b_size*8.
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| 		 * The offset of this buffer is b_size*i, so the bit offset
 | |
| 		 * of this buffer is b_size*8*i.
 | |
| 		 */
 | |
| 		ecc = (u16)ocfs2_hamming_encode(ecc, bhs[i]->b_data,
 | |
| 						bhs[i]->b_size * 8,
 | |
| 						bhs[i]->b_size * 8 * i);
 | |
| 	}
 | |
| 
 | |
| 	/*
 | |
| 	 * No ecc'd ocfs2 structure is larger than 4K, so ecc will be no
 | |
| 	 * larger than 16 bits.
 | |
| 	 */
 | |
| 	BUG_ON(ecc > USHRT_MAX);
 | |
| 
 | |
| 	bc->bc_crc32e = cpu_to_le32(crc);
 | |
| 	bc->bc_ecc = cpu_to_le16((u16)ecc);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * This function validates existing check information on a list of
 | |
|  * buffer_heads.  Like _compute_bhs, the function will take care of
 | |
|  * zeroing bc before calculating check codes.  If bc is not a pointer
 | |
|  * inside data, the caller must have zeroed any inline
 | |
|  * ocfs2_block_check structures.
 | |
|  *
 | |
|  * Again, the data passed in should be the on-disk endian.
 | |
|  */
 | |
| int ocfs2_block_check_validate_bhs(struct buffer_head **bhs, int nr,
 | |
| 				   struct ocfs2_block_check *bc,
 | |
| 				   struct ocfs2_blockcheck_stats *stats)
 | |
| {
 | |
| 	int i, rc = 0;
 | |
| 	u32 bc_crc32e;
 | |
| 	u16 bc_ecc;
 | |
| 	u32 crc, ecc, fix;
 | |
| 
 | |
| 	BUG_ON(nr < 0);
 | |
| 
 | |
| 	if (!nr)
 | |
| 		return 0;
 | |
| 
 | |
| 	ocfs2_blockcheck_inc_check(stats);
 | |
| 
 | |
| 	bc_crc32e = le32_to_cpu(bc->bc_crc32e);
 | |
| 	bc_ecc = le16_to_cpu(bc->bc_ecc);
 | |
| 
 | |
| 	memset(bc, 0, sizeof(struct ocfs2_block_check));
 | |
| 
 | |
| 	/* Fast path - if the crc32 validates, we're good to go */
 | |
| 	for (i = 0, crc = ~0; i < nr; i++)
 | |
| 		crc = crc32_le(crc, bhs[i]->b_data, bhs[i]->b_size);
 | |
| 	if (crc == bc_crc32e)
 | |
| 		goto out;
 | |
| 
 | |
| 	ocfs2_blockcheck_inc_failure(stats);
 | |
| 	mlog(ML_ERROR,
 | |
| 	     "CRC32 failed: stored: %u, computed %u.  Applying ECC.\n",
 | |
| 	     (unsigned int)bc_crc32e, (unsigned int)crc);
 | |
| 
 | |
| 	/* Ok, try ECC fixups */
 | |
| 	for (i = 0, ecc = 0; i < nr; i++) {
 | |
| 		/*
 | |
| 		 * The number of bits in a buffer is obviously b_size*8.
 | |
| 		 * The offset of this buffer is b_size*i, so the bit offset
 | |
| 		 * of this buffer is b_size*8*i.
 | |
| 		 */
 | |
| 		ecc = (u16)ocfs2_hamming_encode(ecc, bhs[i]->b_data,
 | |
| 						bhs[i]->b_size * 8,
 | |
| 						bhs[i]->b_size * 8 * i);
 | |
| 	}
 | |
| 	fix = ecc ^ bc_ecc;
 | |
| 	for (i = 0; i < nr; i++) {
 | |
| 		/*
 | |
| 		 * Try the fix against each buffer.  It will only affect
 | |
| 		 * one of them.
 | |
| 		 */
 | |
| 		ocfs2_hamming_fix(bhs[i]->b_data, bhs[i]->b_size * 8,
 | |
| 				  bhs[i]->b_size * 8 * i, fix);
 | |
| 	}
 | |
| 
 | |
| 	/* And check the crc32 again */
 | |
| 	for (i = 0, crc = ~0; i < nr; i++)
 | |
| 		crc = crc32_le(crc, bhs[i]->b_data, bhs[i]->b_size);
 | |
| 	if (crc == bc_crc32e) {
 | |
| 		ocfs2_blockcheck_inc_recover(stats);
 | |
| 		goto out;
 | |
| 	}
 | |
| 
 | |
| 	mlog(ML_ERROR, "Fixed CRC32 failed: stored: %u, computed %u\n",
 | |
| 	     (unsigned int)bc_crc32e, (unsigned int)crc);
 | |
| 
 | |
| 	rc = -EIO;
 | |
| 
 | |
| out:
 | |
| 	bc->bc_crc32e = cpu_to_le32(bc_crc32e);
 | |
| 	bc->bc_ecc = cpu_to_le16(bc_ecc);
 | |
| 
 | |
| 	return rc;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * These are the main API.  They check the superblock flag before
 | |
|  * calling the underlying operations.
 | |
|  *
 | |
|  * They expect the buffer(s) to be in disk format.
 | |
|  */
 | |
| void ocfs2_compute_meta_ecc(struct super_block *sb, void *data,
 | |
| 			    struct ocfs2_block_check *bc)
 | |
| {
 | |
| 	if (ocfs2_meta_ecc(OCFS2_SB(sb)))
 | |
| 		ocfs2_block_check_compute(data, sb->s_blocksize, bc);
 | |
| }
 | |
| 
 | |
| int ocfs2_validate_meta_ecc(struct super_block *sb, void *data,
 | |
| 			    struct ocfs2_block_check *bc)
 | |
| {
 | |
| 	int rc = 0;
 | |
| 	struct ocfs2_super *osb = OCFS2_SB(sb);
 | |
| 
 | |
| 	if (ocfs2_meta_ecc(osb))
 | |
| 		rc = ocfs2_block_check_validate(data, sb->s_blocksize, bc,
 | |
| 						&osb->osb_ecc_stats);
 | |
| 
 | |
| 	return rc;
 | |
| }
 | |
| 
 | |
| void ocfs2_compute_meta_ecc_bhs(struct super_block *sb,
 | |
| 				struct buffer_head **bhs, int nr,
 | |
| 				struct ocfs2_block_check *bc)
 | |
| {
 | |
| 	if (ocfs2_meta_ecc(OCFS2_SB(sb)))
 | |
| 		ocfs2_block_check_compute_bhs(bhs, nr, bc);
 | |
| }
 | |
| 
 | |
| int ocfs2_validate_meta_ecc_bhs(struct super_block *sb,
 | |
| 				struct buffer_head **bhs, int nr,
 | |
| 				struct ocfs2_block_check *bc)
 | |
| {
 | |
| 	int rc = 0;
 | |
| 	struct ocfs2_super *osb = OCFS2_SB(sb);
 | |
| 
 | |
| 	if (ocfs2_meta_ecc(osb))
 | |
| 		rc = ocfs2_block_check_validate_bhs(bhs, nr, bc,
 | |
| 						    &osb->osb_ecc_stats);
 | |
| 
 | |
| 	return rc;
 | |
| }
 | |
| 
 | 
