mirror of
https://github.com/kdave/btrfs-progs
synced 2024-12-22 06:10:06 +00:00
0173e6eb83
raid6.c is built without access to the prototypes of functions it exports. warning: symbol 'raid6_gen_syndrome' was not declared. Should it be static? They could be changed and get out of sync of the exported prototypes without errors. So we add disk-io.h, and its dependency ctree.h, so that it has a chance to check that its exported prototypes are correct. Signed-off-by: Zach Brown <zab@redhat.com> Signed-off-by: David Sterba <dsterba@suse.cz> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
102 lines
2.5 KiB
C
102 lines
2.5 KiB
C
/* -*- linux-c -*- ------------------------------------------------------- *
|
|
*
|
|
* Copyright 2002-2004 H. Peter Anvin - 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 as published by
|
|
* the Free Software Foundation, Inc., 53 Temple Place Ste 330,
|
|
* Boston MA 02111-1307, USA; either version 2 of the License, or
|
|
* (at your option) any later version; incorporated herein by reference.
|
|
*
|
|
* ----------------------------------------------------------------------- */
|
|
|
|
/*
|
|
* raid6int1.c
|
|
*
|
|
* 1-way unrolled portable integer math RAID-6 instruction set
|
|
*
|
|
* This file was postprocessed using unroll.pl and then ported to userspace
|
|
*/
|
|
#include <stdint.h>
|
|
#include <unistd.h>
|
|
#include "kerncompat.h"
|
|
#include "ctree.h"
|
|
#include "disk-io.h"
|
|
|
|
/*
|
|
* This is the C data type to use
|
|
*/
|
|
|
|
/* Change this from BITS_PER_LONG if there is something better... */
|
|
#if BITS_PER_LONG == 64
|
|
# define NBYTES(x) ((x) * 0x0101010101010101UL)
|
|
# define NSIZE 8
|
|
# define NSHIFT 3
|
|
typedef uint64_t unative_t;
|
|
#else
|
|
# define NBYTES(x) ((x) * 0x01010101U)
|
|
# define NSIZE 4
|
|
# define NSHIFT 2
|
|
typedef uint32_t unative_t;
|
|
#endif
|
|
|
|
/*
|
|
* These sub-operations are separate inlines since they can sometimes be
|
|
* specially optimized using architecture-specific hacks.
|
|
*/
|
|
|
|
/*
|
|
* The SHLBYTE() operation shifts each byte left by 1, *not*
|
|
* rolling over into the next byte
|
|
*/
|
|
static inline __attribute_const__ unative_t SHLBYTE(unative_t v)
|
|
{
|
|
unative_t vv;
|
|
|
|
vv = (v << 1) & NBYTES(0xfe);
|
|
return vv;
|
|
}
|
|
|
|
/*
|
|
* The MASK() operation returns 0xFF in any byte for which the high
|
|
* bit is 1, 0x00 for any byte for which the high bit is 0.
|
|
*/
|
|
static inline __attribute_const__ unative_t MASK(unative_t v)
|
|
{
|
|
unative_t vv;
|
|
|
|
vv = v & NBYTES(0x80);
|
|
vv = (vv << 1) - (vv >> 7); /* Overflow on the top bit is OK */
|
|
return vv;
|
|
}
|
|
|
|
|
|
void raid6_gen_syndrome(int disks, size_t bytes, void **ptrs)
|
|
{
|
|
uint8_t **dptr = (uint8_t **)ptrs;
|
|
uint8_t *p, *q;
|
|
int d, z, z0;
|
|
|
|
unative_t wd0, wq0, wp0, w10, w20;
|
|
|
|
z0 = disks - 3; /* Highest data disk */
|
|
p = dptr[z0+1]; /* XOR parity */
|
|
q = dptr[z0+2]; /* RS syndrome */
|
|
|
|
for ( d = 0 ; d < bytes ; d += NSIZE*1 ) {
|
|
wq0 = wp0 = *(unative_t *)&dptr[z0][d+0*NSIZE];
|
|
for ( z = z0-1 ; z >= 0 ; z-- ) {
|
|
wd0 = *(unative_t *)&dptr[z][d+0*NSIZE];
|
|
wp0 ^= wd0;
|
|
w20 = MASK(wq0);
|
|
w10 = SHLBYTE(wq0);
|
|
w20 &= NBYTES(0x1d);
|
|
w10 ^= w20;
|
|
wq0 = w10 ^ wd0;
|
|
}
|
|
*(unative_t *)&p[d+NSIZE*0] = wp0;
|
|
*(unative_t *)&q[d+NSIZE*0] = wq0;
|
|
}
|
|
}
|
|
|