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authorDavid Woodhouse <dwmw2@tylersburg.infradead.org>2009-07-13 11:35:12 +0100
committerDavid Woodhouse <David.Woodhouse@intel.com>2009-10-29 14:38:47 +0000
commitf5e70d0fe3ea990cfb3fc8d7f76a719adcb1e0b5 (patch)
tree1794eb51814228ff76f672a541100ad62dd791c9 /drivers/md/raid6algos.c
parent17d857be649a21ca90008c6dc425d849fa83db5c (diff)
md: Factor out RAID6 algorithms into lib/
We'll want to use these in btrfs too. Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'drivers/md/raid6algos.c')
-rw-r--r--drivers/md/raid6algos.c171
1 files changed, 0 insertions, 171 deletions
diff --git a/drivers/md/raid6algos.c b/drivers/md/raid6algos.c
deleted file mode 100644
index 866215ac7f25..000000000000
--- a/drivers/md/raid6algos.c
+++ /dev/null
@@ -1,171 +0,0 @@
-/* -*- linux-c -*- ------------------------------------------------------- *
- *
- * Copyright 2002 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.
- *
- * ----------------------------------------------------------------------- */
-
-/*
- * raid6algos.c
- *
- * Algorithm list and algorithm selection for RAID-6
- */
-
-#include <linux/raid/pq.h>
-#ifndef __KERNEL__
-#include <sys/mman.h>
-#include <stdio.h>
-#else
-#if !RAID6_USE_EMPTY_ZERO_PAGE
-/* In .bss so it's zeroed */
-const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(256)));
-EXPORT_SYMBOL(raid6_empty_zero_page);
-#endif
-#endif
-
-struct raid6_calls raid6_call;
-EXPORT_SYMBOL_GPL(raid6_call);
-
-/* Various routine sets */
-extern const struct raid6_calls raid6_intx1;
-extern const struct raid6_calls raid6_intx2;
-extern const struct raid6_calls raid6_intx4;
-extern const struct raid6_calls raid6_intx8;
-extern const struct raid6_calls raid6_intx16;
-extern const struct raid6_calls raid6_intx32;
-extern const struct raid6_calls raid6_mmxx1;
-extern const struct raid6_calls raid6_mmxx2;
-extern const struct raid6_calls raid6_sse1x1;
-extern const struct raid6_calls raid6_sse1x2;
-extern const struct raid6_calls raid6_sse2x1;
-extern const struct raid6_calls raid6_sse2x2;
-extern const struct raid6_calls raid6_sse2x4;
-extern const struct raid6_calls raid6_altivec1;
-extern const struct raid6_calls raid6_altivec2;
-extern const struct raid6_calls raid6_altivec4;
-extern const struct raid6_calls raid6_altivec8;
-
-const struct raid6_calls * const raid6_algos[] = {
- &raid6_intx1,
- &raid6_intx2,
- &raid6_intx4,
- &raid6_intx8,
-#if defined(__ia64__)
- &raid6_intx16,
- &raid6_intx32,
-#endif
-#if defined(__i386__) && !defined(__arch_um__)
- &raid6_mmxx1,
- &raid6_mmxx2,
- &raid6_sse1x1,
- &raid6_sse1x2,
- &raid6_sse2x1,
- &raid6_sse2x2,
-#endif
-#if defined(__x86_64__) && !defined(__arch_um__)
- &raid6_sse2x1,
- &raid6_sse2x2,
- &raid6_sse2x4,
-#endif
-#ifdef CONFIG_ALTIVEC
- &raid6_altivec1,
- &raid6_altivec2,
- &raid6_altivec4,
- &raid6_altivec8,
-#endif
- NULL
-};
-
-#ifdef __KERNEL__
-#define RAID6_TIME_JIFFIES_LG2 4
-#else
-/* Need more time to be stable in userspace */
-#define RAID6_TIME_JIFFIES_LG2 9
-#define time_before(x, y) ((x) < (y))
-#endif
-
-/* Try to pick the best algorithm */
-/* This code uses the gfmul table as convenient data set to abuse */
-
-int __init raid6_select_algo(void)
-{
- const struct raid6_calls * const * algo;
- const struct raid6_calls * best;
- char *syndromes;
- void *dptrs[(65536/PAGE_SIZE)+2];
- int i, disks;
- unsigned long perf, bestperf;
- int bestprefer;
- unsigned long j0, j1;
-
- disks = (65536/PAGE_SIZE)+2;
- for ( i = 0 ; i < disks-2 ; i++ ) {
- dptrs[i] = ((char *)raid6_gfmul) + PAGE_SIZE*i;
- }
-
- /* Normal code - use a 2-page allocation to avoid D$ conflict */
- syndromes = (void *) __get_free_pages(GFP_KERNEL, 1);
-
- if ( !syndromes ) {
- printk("raid6: Yikes! No memory available.\n");
- return -ENOMEM;
- }
-
- dptrs[disks-2] = syndromes;
- dptrs[disks-1] = syndromes + PAGE_SIZE;
-
- bestperf = 0; bestprefer = 0; best = NULL;
-
- for ( algo = raid6_algos ; *algo ; algo++ ) {
- if ( !(*algo)->valid || (*algo)->valid() ) {
- perf = 0;
-
- preempt_disable();
- j0 = jiffies;
- while ( (j1 = jiffies) == j0 )
- cpu_relax();
- while (time_before(jiffies,
- j1 + (1<<RAID6_TIME_JIFFIES_LG2))) {
- (*algo)->gen_syndrome(disks, PAGE_SIZE, dptrs);
- perf++;
- }
- preempt_enable();
-
- if ( (*algo)->prefer > bestprefer ||
- ((*algo)->prefer == bestprefer &&
- perf > bestperf) ) {
- best = *algo;
- bestprefer = best->prefer;
- bestperf = perf;
- }
- printk("raid6: %-8s %5ld MB/s\n", (*algo)->name,
- (perf*HZ) >> (20-16+RAID6_TIME_JIFFIES_LG2));
- }
- }
-
- if (best) {
- printk("raid6: using algorithm %s (%ld MB/s)\n",
- best->name,
- (bestperf*HZ) >> (20-16+RAID6_TIME_JIFFIES_LG2));
- raid6_call = *best;
- } else
- printk("raid6: Yikes! No algorithm found!\n");
-
- free_pages((unsigned long)syndromes, 1);
-
- return best ? 0 : -EINVAL;
-}
-
-static void raid6_exit(void)
-{
- do { } while (0);
-}
-
-subsys_initcall(raid6_select_algo);
-module_exit(raid6_exit);
-MODULE_LICENSE("GPL");