/* -*- 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. * * ----------------------------------------------------------------------- */ /* * raid6int$#.c * * $#-way unrolled portable integer math RAID-6 instruction set * * This file is postprocessed using unroll.pl */ #include <linux/raid/pq.h> /* * This is the C data type to use */ /* Change this from BITS_PER_LONG if there is something better... */ #if BITS_PER_LONG == 64 # define NBYTES(x) ((x) * 0x0101010101010101UL) # define NSIZE 8 # define NSHIFT 3 # define NSTRING "64" typedef u64 unative_t; #else # define NBYTES(x) ((x) * 0x01010101U) # define NSIZE 4 # define NSHIFT 2 # define NSTRING "32" typedef u32 unative_t; #endif /* * IA-64 wants insane amounts of unrolling. On other architectures that * is just a waste of space. */ #if ($# <= 8) || defined(__ia64__) /* * 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; } static void raid6_int$#_gen_syndrome(int disks, size_t bytes, void **ptrs) { u8 **dptr = (u8 **)ptrs; u8 *p, *q; int d, z, z0; unative_t wd$$, wq$$, wp$$, w1$$, w2$$; z0 = disks - 3; /* Highest data disk */ p = dptr[z0+1]; /* XOR parity */ q = dptr[z0+2]; /* RS syndrome */ for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { wq$$ = wp$$ = *(unative_t *)&dptr[z0][d+$$*NSIZE]; for ( z = z0-1 ; z >= 0 ; z-- ) { wd$$ = *(unative_t *)&dptr[z][d+$$*NSIZE]; wp$$ ^= wd$$; w2$$ = MASK(wq$$); w1$$ = SHLBYTE(wq$$); w2$$ &= NBYTES(0x1d); w1$$ ^= w2$$; wq$$ = w1$$ ^ wd$$; } *(unative_t *)&p[d+NSIZE*$$] = wp$$; *(unative_t *)&q[d+NSIZE*$$] = wq$$; } } const struct raid6_calls raid6_intx$# = { raid6_int$#_gen_syndrome, NULL, /* always valid */ "int" NSTRING "x$#", 0 }; #endif