From: "H. Peter Anvin" <hpa@zytor.com>
See Kconfig help for usage details.
---
drivers/md/Kconfig | 33
drivers/md/Makefile | 30
drivers/md/md.c | 14
drivers/md/mktables.c | 125 ++
drivers/md/raid6.h | 144 +++
drivers/md/raid6algos.c | 140 ++
drivers/md/raid6int.uc | 66 +
drivers/md/raid6main.c | 1973 ++++++++++++++++++++++++++++++++++++++++++
drivers/md/raid6mmx.c | 150 +++
drivers/md/raid6recov.c | 133 ++
drivers/md/raid6sse1.c | 171 +++
drivers/md/raid6sse2.c | 270 +++++
drivers/md/raid6test/Makefile | 56 +
drivers/md/raid6test/test.c | 98 ++
drivers/md/raid6x86.h | 242 +++++
drivers/md/unroll.pl | 24
include/linux/raid/md_k.h | 5
17 files changed, 3668 insertions(+), 6 deletions(-)
diff -puN drivers/md/Kconfig~raid6-20040107 drivers/md/Kconfig
--- 25/drivers/md/Kconfig~raid6-20040107 2004-01-07 22:20:04.000000000 -0800
+++ 25-akpm/drivers/md/Kconfig 2004-01-07 22:20:04.000000000 -0800
@@ -107,6 +107,39 @@ config MD_RAID5
If unsure, say Y.
+config MD_RAID6
+ tristate "RAID-6 mode (EXPERIMENTAL)"
+ depends on BLK_DEV_MD && EXPERIMENTAL
+ ---help---
+ WARNING: RAID-6 is currently highly experimental. If you
+ use it, there is no guarantee whatsoever that it won't
+ destroy your data, eat your disk drives, insult your mother,
+ or re-appoint George W. Bush.
+
+ A RAID-6 set of N drives with a capacity of C MB per drive
+ provides the capacity of C * (N - 2) MB, and protects
+ against a failure of any two drives. For a given sector
+ (row) number, (N - 2) drives contain data sectors, and two
+ drives contains two independent redundancy syndromes. Like
+ RAID-5, RAID-6 distributes the syndromes across the drives
+ in one of the available parity distribution methods.
+
+ RAID-6 currently requires a specially patched version of
+ mdadm; the patch is available at:
+
+ ftp://ftp.kernel.org/pub/linux/kernel/people/hpa/
+
+ ... and the mdadm source code at ...
+
+ ftp://ftp.kernel.org/pub/linux/utils/raid/mdadm/
+
+ If you want to use such a RAID-6 set, say Y. To compile
+ this code as a module, choose M here: the module will be
+ called raid6.
+
+
+ If unsure, say N.
+
config MD_MULTIPATH
tristate "Multipath I/O support"
depends on BLK_DEV_MD
diff -puN drivers/md/Makefile~raid6-20040107 drivers/md/Makefile
--- 25/drivers/md/Makefile~raid6-20040107 2004-01-07 22:20:04.000000000 -0800
+++ 25-akpm/drivers/md/Makefile 2004-01-07 22:20:04.000000000 -0800
@@ -4,6 +4,11 @@
dm-mod-objs := dm.o dm-table.o dm-target.o dm-linear.o dm-stripe.o \
dm-ioctl.o
+raid6-objs := raid6main.o raid6algos.o raid6recov.o raid6tables.o \
+ raid6int1.o raid6int2.o raid6int4.o \
+ raid6int8.o raid6int16.o raid6int32.o \
+ raid6mmx.o raid6sse1.o raid6sse2.o
+host-progs := mktables
# Note: link order is important. All raid personalities
# and xor.o must come before md.o, as they each initialise
@@ -14,6 +19,31 @@ obj-$(CONFIG_MD_LINEAR) += linear.o
obj-$(CONFIG_MD_RAID0) += raid0.o
obj-$(CONFIG_MD_RAID1) += raid1.o
obj-$(CONFIG_MD_RAID5) += raid5.o xor.o
+obj-$(CONFIG_MD_RAID6) += raid6.o xor.o
obj-$(CONFIG_MD_MULTIPATH) += multipath.o
obj-$(CONFIG_BLK_DEV_MD) += md.o
obj-$(CONFIG_BLK_DEV_DM) += dm-mod.o
+
+# Files generated that shall be removed upon make clean
+clean-files := raid6int*.c raid6tables.c mktables
+
+$(obj)/raid6int1.c: $(src)/raid6int.uc $(src)/unroll.pl
+ $(PERL) $(src)/unroll.pl 1 < $< > $@ || ( rm -f $@ && exit 1 )
+
+$(obj)/raid6int2.c: $(src)/raid6int.uc $(src)/unroll.pl
+ $(PERL) $(src)/unroll.pl 2 < $< > $@ || ( rm -f $@ && exit 1 )
+
+$(obj)/raid6int4.c: $(src)/raid6int.uc $(src)/unroll.pl
+ $(PERL) $(src)/unroll.pl 4 < $< > $@ || ( rm -f $@ && exit 1 )
+
+$(obj)/raid6int8.c: $(src)/raid6int.uc $(src)/unroll.pl
+ $(PERL) $(src)/unroll.pl 8 < $< > $@ || ( rm -f $@ && exit 1 )
+
+$(obj)/raid6int16.c: $(src)/raid6int.uc $(src)/unroll.pl
+ $(PERL) $(src)/unroll.pl 16 < $< > $@ || ( rm -f $@ && exit 1 )
+
+$(obj)/raid6int32.c: $(src)/raid6int.uc $(src)/unroll.pl
+ $(PERL) $(src)/unroll.pl 32 < $< > $@ || ( rm -f $@ && exit 1 )
+
+$(obj)/raid6tables.c: $(obj)/mktables
+ $(obj)/mktables > $@ || ( rm -f $@ && exit 1 )
diff -puN drivers/md/md.c~raid6-20040107 drivers/md/md.c
--- 25/drivers/md/md.c~raid6-20040107 2004-01-07 22:20:04.000000000 -0800
+++ 25-akpm/drivers/md/md.c 2004-01-07 22:20:04.000000000 -0800
@@ -7,6 +7,7 @@
Changes:
- RAID-1/RAID-5 extensions by Miguel de Icaza, Gadi Oxman, Ingo Molnar
+ - RAID-6 extensions by H. Peter Anvin <hpa@zytor.com>
- boot support for linear and striped mode by Harald Hoyer <HarryH@Royal.Net>
- kerneld support by Boris Tobotras <boris@xtalk.msk.su>
- kmod support by: Cyrus Durgin
@@ -1435,11 +1436,12 @@ static int analyze_sbs(mddev_t * mddev)
goto abort;
}
- if ((mddev->recovery_cp != MaxSector) && ((mddev->level == 1) ||
- (mddev->level == 4) || (mddev->level == 5)))
+ if ((mddev->recovery_cp != MaxSector) &&
+ ((mddev->level == 1) ||
+ ((mddev->level >= 4) && (mddev->level <= 6))))
printk(KERN_ERR "md: md%d: raid array is not clean"
- " -- starting background reconstruction\n",
- mdidx(mddev));
+ " -- starting background reconstruction\n",
+ mdidx(mddev));
return 0;
abort:
@@ -3014,7 +3016,9 @@ static struct file_operations md_seq_fop
int register_md_personality(int pnum, mdk_personality_t *p)
{
if (pnum >= MAX_PERSONALITY) {
- MD_BUG();
+ printk(KERN_ERR
+ "md: tried to install personality %s as nr %d, but max is %lu\n",
+ p->name, pnum, MAX_PERSONALITY-1);
return -EINVAL;
}
diff -puN /dev/null drivers/md/mktables.c
--- /dev/null 2002-08-30 16:31:37.000000000 -0700
+++ 25-akpm/drivers/md/mktables.c 2004-01-07 22:20:04.000000000 -0800
@@ -0,0 +1,125 @@
+#ident "$Id: raid6-20040107.patch,v 1.1 2004/01/08 06:20:43 akpm Exp $"
+/* ----------------------------------------------------------------------- *
+ *
+ * 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,
+ * Bostom MA 02111-1307, USA; either version 2 of the License, or
+ * (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * mktables.c
+ *
+ * Make RAID-6 tables. This is a host user space program to be run at
+ * compile time.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <inttypes.h>
+#include <stdlib.h>
+#include <time.h>
+
+static uint8_t gfmul(uint8_t a, uint8_t b)
+{
+ uint8_t v = 0;
+
+ while ( b ) {
+ if ( b & 1 ) v ^= a;
+ a = (a << 1) ^ (a & 0x80 ? 0x1d : 0);
+ b >>= 1;
+ }
+ return v;
+}
+
+static uint8_t gfpow(uint8_t a, int b)
+{
+ uint8_t v = 1;
+
+ b %= 255;
+ if ( b < 0 )
+ b += 255;
+
+ while ( b ) {
+ if ( b & 1 ) v = gfmul(v,a);
+ a = gfmul(a,a);
+ b >>= 1;
+ }
+ return v;
+}
+
+int main(int argc, char *argv[])
+{
+ int i, j, k;
+ uint8_t v;
+ uint8_t exptbl[256], invtbl[256];
+
+ printf("#include \"raid6.h\"\n");
+
+ /* Compute multiplication table */
+ printf("\nconst u8 __attribute__((aligned(256)))\n"
+ "raid6_gfmul[256][256] =\n"
+ "{\n");
+ for ( i = 0 ; i < 256 ; i++ ) {
+ printf("\t{\n");
+ for ( j = 0 ; j < 256 ; j += 8 ) {
+ printf("\t\t");
+ for ( k = 0 ; k < 8 ; k++ ) {
+ printf("0x%02x, ", gfmul(i,j+k));
+ }
+ printf("\n");
+ }
+ printf("\t},\n");
+ }
+ printf("};\n");
+
+ /* Compute power-of-2 table (exponent) */
+ v = 1;
+ printf("\nconst u8 __attribute__((aligned(256)))\n"
+ "raid6_gfexp[256] =\n"
+ "{\n");
+ for ( i = 0 ; i < 256 ; i += 8 ) {
+ printf("\t");
+ for ( j = 0 ; j < 8 ; j++ ) {
+ exptbl[i+j] = v;
+ printf("0x%02x, ", v);
+ v = gfmul(v,2);
+ if ( v == 1 ) v = 0; /* For entry 255, not a real entry */
+ }
+ printf("\n");
+ }
+ printf("};\n");
+
+ /* Compute inverse table x^-1 == x^254 */
+ printf("\nconst u8 __attribute__((aligned(256)))\n"
+ "raid6_gfinv[256] =\n"
+ "{\n");
+ for ( i = 0 ; i < 256 ; i += 8 ) {
+ printf("\t");
+ for ( j = 0 ; j < 8 ; j++ ) {
+ invtbl[i+j] = v = gfpow(i+j,254);
+ printf("0x%02x, ", v);
+ }
+ printf("\n");
+ }
+ printf("};\n");
+
+ /* Compute inv(2^x + 1) (exponent-xor-inverse) table */
+ printf("\nconst u8 __attribute__((aligned(256)))\n"
+ "raid6_gfexi[256] =\n"
+ "{\n");
+ for ( i = 0 ; i < 256 ; i += 8 ) {
+ printf("\t");
+ for ( j = 0 ; j < 8 ; j++ ) {
+ printf("0x%02x, ", invtbl[exptbl[i+j]^1]);
+ }
+ printf("\n");
+ }
+ printf("};\n\n");
+
+ return 0;
+}
diff -puN /dev/null drivers/md/raid6algos.c
--- /dev/null 2002-08-30 16:31:37.000000000 -0700
+++ 25-akpm/drivers/md/raid6algos.c 2004-01-07 22:20:04.000000000 -0800
@@ -0,0 +1,140 @@
+/* -*- 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,
+ * Bostom 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 "raid6.h"
+#ifndef __KERNEL__
+#include <sys/mman.h>
+#endif
+
+struct raid6_calls 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_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;
+
+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(__x86_64__)
+ &raid6_mmxx1,
+ &raid6_mmxx2,
+ &raid6_sse1x1,
+ &raid6_sse1x2,
+ &raid6_sse2x1,
+ &raid6_sse2x2,
+#endif
+#if defined(__x86_64__)
+ &raid6_sse2x4;
+#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
+#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 ( (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));
+ else
+ printk("raid6: Yikes! No algorithm found!\n");
+
+ raid6_call = *best;
+
+ free_pages((unsigned long)syndromes, 1);
+
+ return best ? 0 : -EINVAL;
+}
diff -puN /dev/null drivers/md/raid6.h
--- /dev/null 2002-08-30 16:31:37.000000000 -0700
+++ 25-akpm/drivers/md/raid6.h 2004-01-07 22:20:04.000000000 -0800
@@ -0,0 +1,144 @@
+/* -*- linux-c -*- ------------------------------------------------------- *
+ *
+ * Copyright 2003 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,
+ * Bostom MA 02111-1307, USA; either version 2 of the License, or
+ * (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+#ifndef LINUX_RAID_RAID6_H
+#define LINUX_RAID_RAID6_H
+
+#ifdef __KERNEL__
+
+/* Set to 1 to use kernel-wide empty_zero_page */
+#define RAID6_USE_EMPTY_ZERO_PAGE 0
+
+#include <linux/module.h>
+#include <linux/stddef.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/mempool.h>
+#include <linux/list.h>
+#include <linux/vmalloc.h>
+#include <linux/raid/md.h>
+#include <linux/raid/raid5.h>
+
+typedef raid5_conf_t raid6_conf_t; /* Same configuration */
+
+/* Additional compute_parity mode -- updates the parity w/o LOCKING */
+#define UPDATE_PARITY 4
+
+/* We need a pre-zeroed page... if we don't want to use the kernel-provided
+ one define it here */
+#if RAID6_USE_EMPTY_ZERO_PAGE
+# define raid6_empty_zero_page empty_zero_page
+#else
+extern const char raid6_empty_zero_page[PAGE_SIZE];
+#endif
+
+#else /* ! __KERNEL__ */
+/* Used for testing in user space */
+
+#include <stddef.h>
+#include <sys/types.h>
+#include <inttypes.h>
+#include <errno.h>
+#include <sys/mman.h>
+
+typedef uint8_t u8;
+typedef uint16_t u16;
+typedef uint32_t u32;
+typedef uint64_t u64;
+
+#ifndef PAGE_SIZE
+# define PAGE_SIZE 4096
+#endif
+extern const char raid6_empty_zero_page[PAGE_SIZE];
+
+#define __init
+#define __exit
+
+#define preempt_enable()
+#define preempt_disable()
+
+#endif /* __KERNEL__ */
+
+/* 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
+
+/* Routine choices */
+struct raid6_calls {
+ void (*gen_syndrome)(int, size_t, void **);
+ int (*valid)(void); /* Returns 1 if this routine set is usable */
+ const char *name; /* Name of this routine set */
+ int prefer; /* Has special performance attribute */
+};
+
+/* Selected algorithm */
+extern struct raid6_calls raid6_call;
+
+/* Algorithm list */
+extern const struct raid6_calls * const raid6_algos[];
+int raid6_select_algo(void);
+
+/* Return values from chk_syndrome */
+#define RAID6_OK 0
+#define RAID6_P_BAD 1
+#define RAID6_Q_BAD 2
+#define RAID6_PQ_BAD 3
+
+/* Galois field tables */
+extern const u8 raid6_gfmul[256][256] __attribute__((aligned(256)));
+extern const u8 raid6_gfexp[256] __attribute__((aligned(256)));
+extern const u8 raid6_gfinv[256] __attribute__((aligned(256)));
+extern const u8 raid6_gfexi[256] __attribute__((aligned(256)));
+
+/* Recovery routines */
+void raid6_2data_recov(int disks, size_t bytes, int faila, int failb, void **ptrs);
+void raid6_datap_recov(int disks, size_t bytes, int faila, void **ptrs);
+void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, void **ptrs);
+
+/* Some definitions to allow code to be compiled for testing in userspace */
+#ifndef __KERNEL__
+
+# define jiffies raid6_jiffies()
+# define printk printf
+# define GFP_KERNEL 0
+# define __get_free_pages(x,y) ((unsigned long)mmap(NULL, PAGE_SIZE << (y), PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, 0, 0))
+# define free_pages(x,y) munmap((void *)(x), (y)*PAGE_SIZE)
+
+static inline void cpu_relax(void)
+{
+ /* Nothing */
+}
+
+#undef HZ
+#define HZ 1000
+static inline uint32_t raid6_jiffies(void)
+{
+ struct timeval tv;
+ gettimeofday(&tv, NULL);
+ return tv.tv_sec*1000 + tv.tv_usec/1000;
+}
+
+#endif /* ! __KERNEL__ */
+
+#endif /* LINUX_RAID_RAID6_H */
diff -puN /dev/null drivers/md/raid6int.uc
--- /dev/null 2002-08-30 16:31:37.000000000 -0700
+++ 25-akpm/drivers/md/raid6int.uc 2004-01-07 22:20:04.000000000 -0800
@@ -0,0 +1,66 @@
+/* -*- 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,
+ * Bostom MA 02111-1307, USA; either version 2 of the License, or
+ * (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * raid6int$#.c
+ *
+ * $#-way unrolled portable integer math RAID-6 instruction set
+ *
+ * This file is postprocessed using unroller.pl
+ */
+
+#include "raid6.h"
+
+/*
+ * IA-64 wants insane amounts of unrolling. On other architectures that
+ * is just a waste of space.
+ */
+
+#if ($# <= 8) || defined(_ia64__)
+
+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$$ = wq$$ & NBYTES(0x80);
+ w1$$ = (wq$$ << 1) & NBYTES(0xfe);
+ w2$$ = (w2$$ << 1) - (w2$$ >> 7);
+ w2$$ &= 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
diff -puN /dev/null drivers/md/raid6main.c
--- /dev/null 2002-08-30 16:31:37.000000000 -0700
+++ 25-akpm/drivers/md/raid6main.c 2004-01-07 22:20:04.000000000 -0800
@@ -0,0 +1,1973 @@
+/*
+ * raid6main.c : Multiple Devices driver for Linux
+ * Copyright (C) 1996, 1997 Ingo Molnar, Miguel de Icaza, Gadi Oxman
+ * Copyright (C) 1999, 2000 Ingo Molnar
+ * Copyright (C) 2002, 2003 H. Peter Anvin
+ *
+ * RAID-6 management functions. This code is derived from raid5.c.
+ * Last merge from raid5.c bkcvs version 1.78.
+ *
+ * Thanks to Penguin Computing for making the RAID-6 development possible
+ * by donating a test server!
+ *
+ * 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; either version 2, or (at your option)
+ * any later version.
+ *
+ * You should have received a copy of the GNU General Public License
+ * (for example /usr/src/linux/COPYING); if not, write to the Free
+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/highmem.h>
+#include <asm/bitops.h>
+#include <asm/atomic.h>
+#include "raid6.h"
+
+/*
+ * Stripe cache
+ */
+
+#define NR_STRIPES 256
+#define STRIPE_SIZE PAGE_SIZE
+#define STRIPE_SHIFT (PAGE_SHIFT - 9)
+#define STRIPE_SECTORS (STRIPE_SIZE>>9)
+#define IO_THRESHOLD 1
+#define HASH_PAGES 1
+#define HASH_PAGES_ORDER 0
+#define NR_HASH (HASH_PAGES * PAGE_SIZE / sizeof(struct stripe_head *))
+#define HASH_MASK (NR_HASH - 1)
+
+#define stripe_hash(conf, sect) ((conf)->stripe_hashtbl[((sect) >> STRIPE_SHIFT) & HASH_MASK])
+
+/* bio's attached to a stripe+device for I/O are linked together in bi_sector
+ * order without overlap. There may be several bio's per stripe+device, and
+ * a bio could span several devices.
+ * When walking this list for a particular stripe+device, we must never proceed
+ * beyond a bio that extends past this device, as the next bio might no longer
+ * be valid.
+ * This macro is used to determine the 'next' bio in the list, given the sector
+ * of the current stripe+device
+ */
+#define r5_next_bio(bio, sect) ( ( bio->bi_sector + (bio->bi_size>>9) < sect + STRIPE_SECTORS) ? bio->bi_next : NULL)
+/*
+ * The following can be used to debug the driver
+ */
+#define RAID6_DEBUG 0 /* Extremely verbose printk */
+#define RAID6_PARANOIA 1 /* Check spinlocks */
+#define RAID6_DUMPSTATE 0 /* Include stripe cache state in /proc/mdstat */
+#if RAID6_PARANOIA && CONFIG_SMP
+# define CHECK_DEVLOCK() if (!spin_is_locked(&conf->device_lock)) BUG()
+#else
+# define CHECK_DEVLOCK()
+#endif
+
+#define PRINTK(x...) ((void)(RAID6_DEBUG && printk(KERN_DEBUG x)))
+#if RAID6_DEBUG
+#undef inline
+#undef __inline__
+#define inline
+#define __inline__
+#endif
+
+#if !RAID6_USE_EMPTY_ZERO_PAGE
+/* In .bss so it's zeroed */
+const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(256)));
+#endif
+
+static inline int raid6_next_disk(int disk, int raid_disks)
+{
+ disk++;
+ return (disk < raid_disks) ? disk : 0;
+}
+
+static void print_raid6_conf (raid6_conf_t *conf);
+
+static inline void __release_stripe(raid6_conf_t *conf, struct stripe_head *sh)
+{
+ if (atomic_dec_and_test(&sh->count)) {
+ if (!list_empty(&sh->lru))
+ BUG();
+ if (atomic_read(&conf->active_stripes)==0)
+ BUG();
+ if (test_bit(STRIPE_HANDLE, &sh->state)) {
+ if (test_bit(STRIPE_DELAYED, &sh->state))
+ list_add_tail(&sh->lru, &conf->delayed_list);
+ else
+ list_add_tail(&sh->lru, &conf->handle_list);
+ md_wakeup_thread(conf->mddev->thread);
+ } else {
+ if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) {
+ atomic_dec(&conf->preread_active_stripes);
+ if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD)
+ md_wakeup_thread(conf->mddev->thread);
+ }
+ list_add_tail(&sh->lru, &conf->inactive_list);
+ atomic_dec(&conf->active_stripes);
+ if (!conf->inactive_blocked ||
+ atomic_read(&conf->active_stripes) < (NR_STRIPES*3/4))
+ wake_up(&conf->wait_for_stripe);
+ }
+ }
+}
+static void release_stripe(struct stripe_head *sh)
+{
+ raid6_conf_t *conf = sh->raid_conf;
+ unsigned long flags;
+
+ spin_lock_irqsave(&conf->device_lock, flags);
+ __release_stripe(conf, sh);
+ spin_unlock_irqrestore(&conf->device_lock, flags);
+}
+
+static void remove_hash(struct stripe_head *sh)
+{
+ PRINTK("remove_hash(), stripe %llu\n", (unsigned long long)sh->sector);
+
+ if (sh->hash_pprev) {
+ if (sh->hash_next)
+ sh->hash_next->hash_pprev = sh->hash_pprev;
+ *sh->hash_pprev = sh->hash_next;
+ sh->hash_pprev = NULL;
+ }
+}
+
+static __inline__ void insert_hash(raid6_conf_t *conf, struct stripe_head *sh)
+{
+ struct stripe_head **shp = &stripe_hash(conf, sh->sector);
+
+ PRINTK("insert_hash(), stripe %llu\n", (unsigned long long)sh->sector);
+
+ CHECK_DEVLOCK();
+ if ((sh->hash_next = *shp) != NULL)
+ (*shp)->hash_pprev = &sh->hash_next;
+ *shp = sh;
+ sh->hash_pprev = shp;
+}
+
+
+/* find an idle stripe, make sure it is unhashed, and return it. */
+static struct stripe_head *get_free_stripe(raid6_conf_t *conf)
+{
+ struct stripe_head *sh = NULL;
+ struct list_head *first;
+
+ CHECK_DEVLOCK();
+ if (list_empty(&conf->inactive_list))
+ goto out;
+ first = conf->inactive_list.next;
+ sh = list_entry(first, struct stripe_head, lru);
+ list_del_init(first);
+ remove_hash(sh);
+ atomic_inc(&conf->active_stripes);
+out:
+ return sh;
+}
+
+static void shrink_buffers(struct stripe_head *sh, int num)
+{
+ struct page *p;
+ int i;
+
+ for (i=0; i<num ; i++) {
+ p = sh->dev[i].page;
+ if (!p)
+ continue;
+ sh->dev[i].page = NULL;
+ page_cache_release(p);
+ }
+}
+
+static int grow_buffers(struct stripe_head *sh, int num)
+{
+ int i;
+
+ for (i=0; i<num; i++) {
+ struct page *page;
+
+ if (!(page = alloc_page(GFP_KERNEL))) {
+ return 1;
+ }
+ sh->dev[i].page = page;
+ }
+ return 0;
+}
+
+static void raid6_build_block (struct stripe_head *sh, int i);
+
+static inline void init_stripe(struct stripe_head *sh, unsigned long sector, int pd_idx)
+{
+ raid6_conf_t *conf = sh->raid_conf;
+ int disks = conf->raid_disks, i;
+
+ if (atomic_read(&sh->count) != 0)
+ BUG();
+ if (test_bit(STRIPE_HANDLE, &sh->state))
+ BUG();
+
+ CHECK_DEVLOCK();
+ PRINTK("init_stripe called, stripe %llu\n",
+ (unsigned long long)sh->sector);
+
+ remove_hash(sh);
+
+ sh->sector = sector;
+ sh->pd_idx = pd_idx;
+ sh->state = 0;
+
+ for (i=disks; i--; ) {
+ struct r5dev *dev = &sh->dev[i];
+
+ if (dev->toread || dev->towrite || dev->written ||
+ test_bit(R5_LOCKED, &dev->flags)) {
+ PRINTK("sector=%llx i=%d %p %p %p %d\n",
+ (unsigned long long)sh->sector, i, dev->toread,
+ dev->towrite, dev->written,
+ test_bit(R5_LOCKED, &dev->flags));
+ BUG();
+ }
+ dev->flags = 0;
+ raid6_build_block(sh, i);
+ }
+ insert_hash(conf, sh);
+}
+
+static struct stripe_head *__find_stripe(raid6_conf_t *conf, unsigned long sector)
+{
+ struct stripe_head *sh;
+
+ CHECK_DEVLOCK();
+ PRINTK("__find_stripe, sector %lu\n", sector);
+ for (sh = stripe_hash(conf, sector); sh; sh = sh->hash_next)
+ if (sh->sector == sector)
+ return sh;
+ PRINTK("__stripe %lu not in cache\n", sector);
+ return NULL;
+}
+
+static struct stripe_head *get_active_stripe(raid6_conf_t *conf, unsigned long sector,
+ int pd_idx, int noblock)
+{
+ struct stripe_head *sh;
+
+ PRINTK("get_stripe, sector %lu\n", sector);
+
+ spin_lock_irq(&conf->device_lock);
+
+ do {
+ sh = __find_stripe(conf, sector);
+ if (!sh) {
+ if (!conf->inactive_blocked)
+ sh = get_free_stripe(conf);
+ if (noblock && sh == NULL)
+ break;
+ if (!sh) {
+ conf->inactive_blocked = 1;
+ wait_event_lock_irq(conf->wait_for_stripe,
+ !list_empty(&conf->inactive_list) &&
+ (atomic_read(&conf->active_stripes) < (NR_STRIPES *3/4)
+ || !conf->inactive_blocked),
+ conf->device_lock);
+ conf->inactive_blocked = 0;
+ } else
+ init_stripe(sh, sector, pd_idx);
+ } else {
+ if (atomic_read(&sh->count)) {
+ if (!list_empty(&sh->lru))
+ BUG();
+ } else {
+ if (!test_bit(STRIPE_HANDLE, &sh->state))
+ atomic_inc(&conf->active_stripes);
+ if (list_empty(&sh->lru))
+ BUG();
+ list_del_init(&sh->lru);
+ }
+ }
+ } while (sh == NULL);
+
+ if (sh)
+ atomic_inc(&sh->count);
+
+ spin_unlock_irq(&conf->device_lock);
+ return sh;
+}
+
+static int grow_stripes(raid6_conf_t *conf, int num)
+{
+ struct stripe_head *sh;
+ kmem_cache_t *sc;
+ int devs = conf->raid_disks;
+
+ sprintf(conf->cache_name, "md/raid6-%d", conf->mddev->__minor);
+
+ sc = kmem_cache_create(conf->cache_name,
+ sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev),
+ 0, 0, NULL, NULL);
+ if (!sc)
+ return 1;
+ conf->slab_cache = sc;
+ while (num--) {
+ sh = kmem_cache_alloc(sc, GFP_KERNEL);
+ if (!sh)
+ return 1;
+ memset(sh, 0, sizeof(*sh) + (devs-1)*sizeof(struct r5dev));
+ sh->raid_conf = conf;
+ sh->lock = SPIN_LOCK_UNLOCKED;
+
+ if (grow_buffers(sh, conf->raid_disks)) {
+ shrink_buffers(sh, conf->raid_disks);
+ kmem_cache_free(sc, sh);
+ return 1;
+ }
+ /* we just created an active stripe so... */
+ atomic_set(&sh->count, 1);
+ atomic_inc(&conf->active_stripes);
+ INIT_LIST_HEAD(&sh->lru);
+ release_stripe(sh);
+ }
+ return 0;
+}
+
+static void shrink_stripes(raid6_conf_t *conf)
+{
+ struct stripe_head *sh;
+
+ while (1) {
+ spin_lock_irq(&conf->device_lock);
+ sh = get_free_stripe(conf);
+ spin_unlock_irq(&conf->device_lock);
+ if (!sh)
+ break;
+ if (atomic_read(&sh->count))
+ BUG();
+ shrink_buffers(sh, conf->raid_disks);
+ kmem_cache_free(conf->slab_cache, sh);
+ atomic_dec(&conf->active_stripes);
+ }
+ kmem_cache_destroy(conf->slab_cache);
+ conf->slab_cache = NULL;
+}
+
+static int raid6_end_read_request (struct bio * bi, unsigned int bytes_done,
+ int error)
+{
+ struct stripe_head *sh = bi->bi_private;
+ raid6_conf_t *conf = sh->raid_conf;
+ int disks = conf->raid_disks, i;
+ int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags);
+
+ if (bi->bi_size)
+ return 1;
+
+ for (i=0 ; i<disks; i++)
+ if (bi == &sh->dev[i].req)
+ break;
+
+ PRINTK("end_read_request %llu/%d, count: %d, uptodate %d.\n",
+ (unsigned long long)sh->sector, i, atomic_read(&sh->count),
+ uptodate);
+ if (i == disks) {
+ BUG();
+ return 0;
+ }
+
+ if (uptodate) {
+#if 0
+ struct bio *bio;
+ unsigned long flags;
+ spin_lock_irqsave(&conf->device_lock, flags);
+ /* we can return a buffer if we bypassed the cache or
+ * if the top buffer is not in highmem. If there are
+ * multiple buffers, leave the extra work to
+ * handle_stripe
+ */
+ buffer = sh->bh_read[i];
+ if (buffer &&
+ (!PageHighMem(buffer->b_page)
+ || buffer->b_page == bh->b_page )
+ ) {
+ sh->bh_read[i] = buffer->b_reqnext;
+ buffer->b_reqnext = NULL;
+ } else
+ buffer = NULL;
+ spin_unlock_irqrestore(&conf->device_lock, flags);
+ if (sh->bh_page[i]==bh->b_page)
+ set_buffer_uptodate(bh);
+ if (buffer) {
+ if (buffer->b_page != bh->b_page)
+ memcpy(buffer->b_data, bh->b_data, bh->b_size);
+ buffer->b_end_io(buffer, 1);
+ }
+#else
+ set_bit(R5_UPTODATE, &sh->dev[i].flags);
+#endif
+ } else {
+ md_error(conf->mddev, conf->disks[i].rdev);
+ clear_bit(R5_UPTODATE, &sh->dev[i].flags);
+ }
+ atomic_dec(&conf->disks[i].rdev->nr_pending);
+#if 0
+ /* must restore b_page before unlocking buffer... */
+ if (sh->bh_page[i] != bh->b_page) {
+ bh->b_page = sh->bh_page[i];
+ bh->b_data = page_address(bh->b_page);
+ clear_buffer_uptodate(bh);
+ }
+#endif
+ clear_bit(R5_LOCKED, &sh->dev[i].flags);
+ set_bit(STRIPE_HANDLE, &sh->state);
+ release_stripe(sh);
+ return 0;
+}
+
+static int raid6_end_write_request (struct bio *bi, unsigned int bytes_done,
+ int error)
+{
+ struct stripe_head *sh = bi->bi_private;
+ raid6_conf_t *conf = sh->raid_conf;
+ int disks = conf->raid_disks, i;
+ unsigned long flags;
+ int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags);
+
+ if (bi->bi_size)
+ return 1;
+
+ for (i=0 ; i<disks; i++)
+ if (bi == &sh->dev[i].req)
+ break;
+
+ PRINTK("end_write_request %llu/%d, count %d, uptodate: %d.\n",
+ (unsigned long long)sh->sector, i, atomic_read(&sh->count),
+ uptodate);
+ if (i == disks) {
+ BUG();
+ return 0;
+ }
+
+ spin_lock_irqsave(&conf->device_lock, flags);
+ if (!uptodate)
+ md_error(conf->mddev, conf->disks[i].rdev);
+
+ atomic_dec(&conf->disks[i].rdev->nr_pending);
+
+ clear_bit(R5_LOCKED, &sh->dev[i].flags);
+ set_bit(STRIPE_HANDLE, &sh->state);
+ __release_stripe(conf, sh);
+ spin_unlock_irqrestore(&conf->device_lock, flags);
+ return 0;
+}
+
+
+static sector_t compute_blocknr(struct stripe_head *sh, int i);
+
+static void raid6_build_block (struct stripe_head *sh, int i)
+{
+ struct r5dev *dev = &sh->dev[i];
+ int pd_idx = sh->pd_idx;
+ int qd_idx = raid6_next_disk(pd_idx, sh->raid_conf->raid_disks);
+
+ bio_init(&dev->req);
+ dev->req.bi_io_vec = &dev->vec;
+ dev->req.bi_vcnt++;
+ dev->vec.bv_page = dev->page;
+ dev->vec.bv_len = STRIPE_SIZE;
+ dev->vec.bv_offset = 0;
+
+ dev->req.bi_sector = sh->sector;
+ dev->req.bi_private = sh;
+
+ dev->flags = 0;
+ if (i != pd_idx && i != qd_idx)
+ dev->sector = compute_blocknr(sh, i);
+}
+
+static void error(mddev_t *mddev, mdk_rdev_t *rdev)
+{
+ char b[BDEVNAME_SIZE];
+ raid6_conf_t *conf = (raid6_conf_t *) mddev->private;
+ PRINTK("raid6: error called\n");
+
+ if (!rdev->faulty) {
+ mddev->sb_dirty = 1;
+ conf->working_disks--;
+ if (rdev->in_sync) {
+ mddev->degraded++;
+ conf->failed_disks++;
+ rdev->in_sync = 0;
+ /*
+ * if recovery was running, make sure it aborts.
+ */
+ set_bit(MD_RECOVERY_ERR, &mddev->recovery);
+ }
+ rdev->faulty = 1;
+ printk (KERN_ALERT
+ "raid6: Disk failure on %s, disabling device."
+ " Operation continuing on %d devices\n",
+ bdevname(rdev->bdev,b), conf->working_disks);
+ }
+}
+
+/*
+ * Input: a 'big' sector number,
+ * Output: index of the data and parity disk, and the sector # in them.
+ */
+static unsigned long raid6_compute_sector(sector_t r_sector, unsigned int raid_disks,
+ unsigned int data_disks, unsigned int * dd_idx,
+ unsigned int * pd_idx, raid6_conf_t *conf)
+{
+ long stripe;
+ unsigned long chunk_number;
+ unsigned int chunk_offset;
+ sector_t new_sector;
+ int sectors_per_chunk = conf->chunk_size >> 9;
+
+ /* First compute the information on this sector */
+
+ /*
+ * Compute the chunk number and the sector offset inside the chunk
+ */
+ chunk_offset = sector_div(r_sector, sectors_per_chunk);
+ chunk_number = r_sector;
+ if ( r_sector != chunk_number ) {
+ printk(KERN_CRIT "raid6: ERROR: r_sector = %llu, chunk_number = %lu\n",
+ (unsigned long long)r_sector, (unsigned long)chunk_number);
+ BUG();
+ }
+
+ /*
+ * Compute the stripe number
+ */
+ stripe = chunk_number / data_disks;
+
+ /*
+ * Compute the data disk and parity disk indexes inside the stripe
+ */
+ *dd_idx = chunk_number % data_disks;
+
+ /*
+ * Select the parity disk based on the user selected algorithm.
+ */
+
+ /**** FIX THIS ****/
+ switch (conf->algorithm) {
+ case ALGORITHM_LEFT_ASYMMETRIC:
+ *pd_idx = raid_disks - 1 - (stripe % raid_disks);
+ if (*pd_idx == raid_disks-1)
+ (*dd_idx)++; /* Q D D D P */
+ else if (*dd_idx >= *pd_idx)
+ (*dd_idx) += 2; /* D D P Q D */
+ break;
+ case ALGORITHM_RIGHT_ASYMMETRIC:
+ *pd_idx = stripe % raid_disks;
+ if (*pd_idx == raid_disks-1)
+ (*dd_idx)++; /* Q D D D P */
+ else if (*dd_idx >= *pd_idx)
+ (*dd_idx) += 2; /* D D P Q D */
+ break;
+ case ALGORITHM_LEFT_SYMMETRIC:
+ *pd_idx = raid_disks - 1 - (stripe % raid_disks);
+ *dd_idx = (*pd_idx + 2 + *dd_idx) % raid_disks;
+ break;
+ case ALGORITHM_RIGHT_SYMMETRIC:
+ *pd_idx = stripe % raid_disks;
+ *dd_idx = (*pd_idx + 2 + *dd_idx) % raid_disks;
+ break;
+ default:
+ printk (KERN_CRIT "raid6: unsupported algorithm %d\n",
+ conf->algorithm);
+ }
+
+ PRINTK("raid6: chunk_number = %lu, pd_idx = %u, dd_idx = %u\n",
+ chunk_number, *pd_idx, *dd_idx);
+
+ /*
+ * Finally, compute the new sector number
+ */
+ new_sector = stripe * sectors_per_chunk + chunk_offset;
+ return new_sector;
+}
+
+
+static sector_t compute_blocknr(struct stripe_head *sh, int i)
+{
+ raid6_conf_t *conf = sh->raid_conf;
+ int raid_disks = conf->raid_disks, data_disks = raid_disks - 2;
+ sector_t new_sector = sh->sector, check;
+ int sectors_per_chunk = conf->chunk_size >> 9;
+ long stripe;
+ int chunk_offset;
+ int chunk_number, dummy1, dummy2, dd_idx = i;
+ sector_t r_sector;
+ int i0 = i;
+
+ chunk_offset = sector_div(new_sector, sectors_per_chunk);
+ stripe = new_sector;
+ if ( new_sector != stripe ) {
+ printk(KERN_CRIT "raid6: ERROR: new_sector = %llu, stripe = %lu\n",
+ (unsigned long long)new_sector, (unsigned long)stripe);
+ BUG();
+ }
+
+ switch (conf->algorithm) {
+ case ALGORITHM_LEFT_ASYMMETRIC:
+ case ALGORITHM_RIGHT_ASYMMETRIC:
+ if (sh->pd_idx == raid_disks-1)
+ i--; /* Q D D D P */
+ else if (i > sh->pd_idx)
+ i -= 2; /* D D P Q D */
+ break;
+ case ALGORITHM_LEFT_SYMMETRIC:
+ case ALGORITHM_RIGHT_SYMMETRIC:
+ if (sh->pd_idx == raid_disks-1)
+ i--; /* Q D D D P */
+ else {
+ /* D D P Q D */
+ if (i < sh->pd_idx)
+ i += raid_disks;
+ i -= (sh->pd_idx + 2);
+ }
+ break;
+ default:
+ printk (KERN_CRIT "raid6: unsupported algorithm %d\n",
+ conf->algorithm);
+ }
+
+ PRINTK("raid6: compute_blocknr: pd_idx = %u, i0 = %u, i = %u\n", sh->pd_idx, i0, i);
+
+ chunk_number = stripe * data_disks + i;
+ r_sector = (sector_t)chunk_number * sectors_per_chunk + chunk_offset;
+
+ check = raid6_compute_sector (r_sector, raid_disks, data_disks, &dummy1, &dummy2, conf);
+ if (check != sh->sector || dummy1 != dd_idx || dummy2 != sh->pd_idx) {
+ printk(KERN_CRIT "raid6: compute_blocknr: map not correct\n");
+ return 0;
+ }
+ return r_sector;
+}
+
+
+
+/*
+ * Copy data between a page in the stripe cache, and one or more bion
+ * The page could align with the middle of the bio, or there could be
+ * several bion, each with several bio_vecs, which cover part of the page
+ * Multiple bion are linked together on bi_next. There may be extras
+ * at the end of this list. We ignore them.
+ */
+static void copy_data(int frombio, struct bio *bio,
+ struct page *page,
+ sector_t sector)
+{
+ char *pa = page_address(page);
+ struct bio_vec *bvl;
+ int i;
+
+ for (;bio && bio->bi_sector < sector+STRIPE_SECTORS;
+ bio = r5_next_bio(bio, sector) ) {
+ int page_offset;
+ if (bio->bi_sector >= sector)
+ page_offset = (signed)(bio->bi_sector - sector) * 512;
+ else
+ page_offset = (signed)(sector - bio->bi_sector) * -512;
+ bio_for_each_segment(bvl, bio, i) {
+ int len = bio_iovec_idx(bio,i)->bv_len;
+ int clen;
+ int b_offset = 0;
+
+ if (page_offset < 0) {
+ b_offset = -page_offset;
+ page_offset += b_offset;
+ len -= b_offset;
+ }
+
+ if (len > 0 && page_offset + len > STRIPE_SIZE)
+ clen = STRIPE_SIZE - page_offset;
+ else clen = len;
+
+ if (clen > 0) {
+ char *ba = __bio_kmap_atomic(bio, i, KM_USER0);
+ if (frombio)
+ memcpy(pa+page_offset, ba+b_offset, clen);
+ else
+ memcpy(ba+b_offset, pa+page_offset, clen);
+ __bio_kunmap_atomic(ba, KM_USER0);
+ }
+ if (clen < len) /* hit end of page */
+ break;
+ page_offset += len;
+ }
+ }
+}
+
+#define check_xor() do { \
+ if (count == MAX_XOR_BLOCKS) { \
+ xor_block(count, STRIPE_SIZE, ptr); \
+ count = 1; \
+ } \
+ } while(0)
+
+/* Compute P and Q syndromes */
+static void compute_parity(struct stripe_head *sh, int method)
+{
+ raid6_conf_t *conf = sh->raid_conf;
+ int i, pd_idx = sh->pd_idx, qd_idx, d0_idx, disks = conf->raid_disks, count;
+ struct bio *chosen;
+ /**** FIX THIS: This could be very bad if disks is close to 256 ****/
+ void *ptrs[disks];
+
+ qd_idx = raid6_next_disk(pd_idx, disks);
+ d0_idx = raid6_next_disk(qd_idx, disks);
+
+ PRINTK("compute_parity, stripe %llu, method %d\n",
+ (unsigned long long)sh->sector, method);
+
+ switch(method) {
+ case READ_MODIFY_WRITE:
+ BUG(); /* READ_MODIFY_WRITE N/A for RAID-6 */
+ case RECONSTRUCT_WRITE:
+ case UPDATE_PARITY: /* Is this right? */
+ for (i= disks; i-- ;)
+ if ( i != pd_idx && i != qd_idx && sh->dev[i].towrite ) {
+ chosen = sh->dev[i].towrite;
+ sh->dev[i].towrite = NULL;
+ if (sh->dev[i].written) BUG();
+ sh->dev[i].written = chosen;
+ }
+ break;
+ case CHECK_PARITY:
+ BUG(); /* Not implemented yet */
+ }
+
+ for (i = disks; i--;)
+ if (sh->dev[i].written) {
+ sector_t sector = sh->dev[i].sector;
+ struct bio *wbi = sh->dev[i].written;
+ while (wbi && wbi->bi_sector < sector + STRIPE_SECTORS) {
+ copy_data(1, wbi, sh->dev[i].page, sector);
+ wbi = r5_next_bio(wbi, sector);
+ }
+
+ set_bit(R5_LOCKED, &sh->dev[i].flags);
+ set_bit(R5_UPTODATE, &sh->dev[i].flags);
+ }
+
+// switch(method) {
+// case RECONSTRUCT_WRITE:
+// case CHECK_PARITY:
+// case UPDATE_PARITY:
+ /* Note that unlike RAID-5, the ordering of the disks matters greatly. */
+ /* FIX: Is this ordering of drives even remotely optimal? */
+ count = 0;
+ i = d0_idx;
+ do {
+ ptrs[count++] = page_address(sh->dev[i].page);
+
+ i = raid6_next_disk(i, disks);
+ } while ( i != d0_idx );
+// break;
+// }
+
+ raid6_call.gen_syndrome(disks, STRIPE_SIZE, ptrs);
+
+ switch(method) {
+ case RECONSTRUCT_WRITE:
+ set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
+ set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags);
+ set_bit(R5_LOCKED, &sh->dev[pd_idx].flags);
+ set_bit(R5_LOCKED, &sh->dev[qd_idx].flags);
+ break;
+ case UPDATE_PARITY:
+ set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
+ set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags);
+ break;
+ }
+}
+
+/* Compute one missing block */
+static void compute_block_1(struct stripe_head *sh, int dd_idx)
+{
+ raid6_conf_t *conf = sh->raid_conf;
+ int i, count, disks = conf->raid_disks;
+ void *ptr[MAX_XOR_BLOCKS], *p;
+ int pd_idx = sh->pd_idx;
+ int qd_idx = raid6_next_disk(pd_idx, disks);
+
+ PRINTK("compute_block_1, stripe %llu, idx %d\n",
+ (unsigned long long)sh->sector, dd_idx);
+
+ if ( dd_idx == qd_idx ) {
+ /* We're actually computing the Q drive */
+ compute_parity(sh, UPDATE_PARITY);
+ } else {
+ ptr[0] = page_address(sh->dev[dd_idx].page);
+ memset(ptr[0], 0, STRIPE_SIZE);
+ count = 1;
+ for (i = disks ; i--; ) {
+ if (i == dd_idx || i == qd_idx)
+ continue;
+ p = page_address(sh->dev[i].page);
+ if (test_bit(R5_UPTODATE, &sh->dev[i].flags))
+ ptr[count++] = p;
+ else
+ PRINTK("compute_block() %d, stripe %llu, %d"
+ " not present\n", dd_idx,
+ (unsigned long long)sh->sector, i);
+
+ check_xor();
+ }
+ if (count != 1)
+ xor_block(count, STRIPE_SIZE, ptr);
+ set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags);
+ }
+}
+
+/* Compute two missing blocks */
+static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2)
+{
+ raid6_conf_t *conf = sh->raid_conf;
+ int i, count, disks = conf->raid_disks;
+ int pd_idx = sh->pd_idx;
+ int qd_idx = raid6_next_disk(pd_idx, disks);
+ int d0_idx = raid6_next_disk(qd_idx, disks);
+ int faila, failb;
+
+ /* faila and failb are disk numbers relative to d0_idx */
+ /* pd_idx become disks-2 and qd_idx become disks-1 */
+ faila = (dd_idx1 < d0_idx) ? dd_idx1+(disks-d0_idx) : dd_idx1-d0_idx;
+ failb = (dd_idx2 < d0_idx) ? dd_idx2+(disks-d0_idx) : dd_idx2-d0_idx;
+
+ BUG_ON(faila == failb);
+ if ( failb < faila ) { int tmp = faila; faila = failb; failb = tmp; }
+
+ PRINTK("compute_block_2, stripe %llu, idx %d,%d (%d,%d)\n",
+ (unsigned long long)sh->sector, dd_idx1, dd_idx2, faila, failb);
+
+ if ( failb == disks-1 ) {
+ /* Q disk is one of the missing disks */
+ if ( faila == disks-2 ) {
+ /* Missing P+Q, just recompute */
+ compute_parity(sh, UPDATE_PARITY);
+ return;
+ } else {
+ /* We're missing D+Q; recompute D from P */
+ compute_block_1(sh, (dd_idx1 == qd_idx) ? dd_idx2 : dd_idx1);
+ compute_parity(sh, UPDATE_PARITY); /* Is this necessary? */
+ return;
+ }
+ }
+
+ /* We're missing D+P or D+D; build pointer table */
+ {
+ /**** FIX THIS: This could be very bad if disks is close to 256 ****/
+ void *ptrs[disks];
+
+ count = 0;
+ i = d0_idx;
+ do {
+ ptrs[count++] = page_address(sh->dev[i].page);
+ i = raid6_next_disk(i, disks);
+ } while ( i != d0_idx );
+
+ if ( failb == disks-2 ) {
+ /* We're missing D+P. */
+ raid6_datap_recov(disks, STRIPE_SIZE, faila, ptrs);
+ } else {
+ /* We're missing D+D. */
+ raid6_2data_recov(disks, STRIPE_SIZE, faila, failb, ptrs);
+ }
+
+ /* Both the above update both missing blocks */
+ set_bit(R5_UPTODATE, &sh->dev[dd_idx1].flags);
+ set_bit(R5_UPTODATE, &sh->dev[dd_idx2].flags);
+ }
+}
+
+
+/*
+ * Each stripe/dev can have one or more bion attached.
+ * toread/towrite point to the first in a chain.
+ * The bi_next chain must be in order.
+ */
+static void add_stripe_bio (struct stripe_head *sh, struct bio *bi, int dd_idx, int forwrite)
+{
+ struct bio **bip;
+ raid6_conf_t *conf = sh->raid_conf;
+
+ PRINTK("adding bh b#%llu to stripe s#%llu\n",
+ (unsigned long long)bi->bi_sector,
+ (unsigned long long)sh->sector);
+
+
+ spin_lock(&sh->lock);
+ spin_lock_irq(&conf->device_lock);
+ if (forwrite)
+ bip = &sh->dev[dd_idx].towrite;
+ else
+ bip = &sh->dev[dd_idx].toread;
+ while (*bip && (*bip)->bi_sector < bi->bi_sector) {
+ BUG_ON((*bip)->bi_sector + ((*bip)->bi_size >> 9) > bi->bi_sector);
+ bip = & (*bip)->bi_next;
+ }
+/* FIXME do I need to worry about overlapping bion */
+ if (*bip && bi->bi_next && (*bip) != bi->bi_next)
+ BUG();
+ if (*bip)
+ bi->bi_next = *bip;
+ *bip = bi;
+ bi->bi_phys_segments ++;
+ spin_unlock_irq(&conf->device_lock);
+ spin_unlock(&sh->lock);
+
+ PRINTK("added bi b#%llu to stripe s#%llu, disk %d.\n",
+ (unsigned long long)bi->bi_sector,
+ (unsigned long long)sh->sector, dd_idx);
+
+ if (forwrite) {
+ /* check if page is coverred */
+ sector_t sector = sh->dev[dd_idx].sector;
+ for (bi=sh->dev[dd_idx].towrite;
+ sector < sh->dev[dd_idx].sector + STRIPE_SECTORS &&
+ bi && bi->bi_sector <= sector;
+ bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) {
+ if (bi->bi_sector + (bi->bi_size>>9) >= sector)
+ sector = bi->bi_sector + (bi->bi_size>>9);
+ }
+ if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS)
+ set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags);
+ }
+}
+
+
+/*
+ * handle_stripe - do things to a stripe.
+ *
+ * We lock the stripe and then examine the state of various bits
+ * to see what needs to be done.
+ * Possible results:
+ * return some read request which now have data
+ * return some write requests which are safely on disc
+ * schedule a read on some buffers
+ * schedule a write of some buffers
+ * return confirmation of parity correctness
+ *
+ * Parity calculations are done inside the stripe lock
+ * buffers are taken off read_list or write_list, and bh_cache buffers
+ * get BH_Lock set before the stripe lock is released.
+ *
+ */
+
+static void handle_stripe(struct stripe_head *sh)
+{
+ raid6_conf_t *conf = sh->raid_conf;
+ int disks = conf->raid_disks;
+ struct bio *return_bi= NULL;
+ struct bio *bi;
+ int i;
+ int syncing;
+ int locked=0, uptodate=0, to_read=0, to_write=0, failed=0, written=0;
+ int non_overwrite = 0;
+ int failed_num[2] = {0, 0};
+ struct r5dev *dev, *pdev, *qdev;
+ int pd_idx = sh->pd_idx;
+ int qd_idx = raid6_next_disk(pd_idx, disks);
+ int p_failed, q_failed;
+
+ PRINTK("handling stripe %llu, state=%#lx cnt=%d, pd_idx=%d, qd_idx=%d\n",
+ (unsigned long long)sh->sector, sh->state, atomic_read(&sh->count),
+ pd_idx, qd_idx);
+
+ spin_lock(&sh->lock);
+ clear_bit(STRIPE_HANDLE, &sh->state);
+ clear_bit(STRIPE_DELAYED, &sh->state);
+
+ syncing = test_bit(STRIPE_SYNCING, &sh->state);
+ /* Now to look around and see what can be done */
+
+ for (i=disks; i--; ) {
+ mdk_rdev_t *rdev;
+ dev = &sh->dev[i];
+ clear_bit(R5_Insync, &dev->flags);
+ clear_bit(R5_Syncio, &dev->flags);
+
+ PRINTK("check %d: state 0x%lx read %p write %p written %p\n",
+ i, dev->flags, dev->toread, dev->towrite, dev->written);
+ /* maybe we can reply to a read */
+ if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread) {
+ struct bio *rbi, *rbi2;
+ PRINTK("Return read for disc %d\n", i);
+ spin_lock_irq(&conf->device_lock);
+ rbi = dev->toread;
+ dev->toread = NULL;
+ spin_unlock_irq(&conf->device_lock);
+ while (rbi && rbi->bi_sector < dev->sector + STRIPE_SECTORS) {
+ copy_data(0, rbi, dev->page, dev->sector);
+ rbi2 = r5_next_bio(rbi, dev->sector);
+ spin_lock_irq(&conf->device_lock);
+ if (--rbi->bi_phys_segments == 0) {
+ rbi->bi_next = return_bi;
+ return_bi = rbi;
+ }
+ spin_unlock_irq(&conf->device_lock);
+ rbi = rbi2;
+ }
+ }
+
+ /* now count some things */
+ if (test_bit(R5_LOCKED, &dev->flags)) locked++;
+ if (test_bit(R5_UPTODATE, &dev->flags)) uptodate++;
+
+
+ if (dev->toread) to_read++;
+ if (dev->towrite) {
+ to_write++;
+ if (!test_bit(R5_OVERWRITE, &dev->flags))
+ non_overwrite++;
+ }
+ if (dev->written) written++;
+ rdev = conf->disks[i].rdev; /* FIXME, should I be looking rdev */
+ if (!rdev || !rdev->in_sync) {
+ if ( failed < 2 )
+ failed_num[failed] = i;
+ failed++;
+ } else
+ set_bit(R5_Insync, &dev->flags);
+ }
+ PRINTK("locked=%d uptodate=%d to_read=%d"
+ " to_write=%d failed=%d failed_num=%d,%d\n",
+ locked, uptodate, to_read, to_write, failed,
+ failed_num[0], failed_num[1]);
+ /* check if the array has lost >2 devices and, if so, some requests might
+ * need to be failed
+ */
+ if (failed > 2 && to_read+to_write+written) {
+ spin_lock_irq(&conf->device_lock);
+ for (i=disks; i--; ) {
+ /* fail all writes first */
+ bi = sh->dev[i].towrite;
+ sh->dev[i].towrite = NULL;
+ if (bi) to_write--;
+
+ while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS){
+ struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector);
+ clear_bit(BIO_UPTODATE, &bi->bi_flags);
+ if (--bi->bi_phys_segments == 0) {
+ md_write_end(conf->mddev);
+ bi->bi_next = return_bi;
+ return_bi = bi;
+ }
+ bi = nextbi;
+ }
+ /* and fail all 'written' */
+ bi = sh->dev[i].written;
+ sh->dev[i].written = NULL;
+ while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS) {
+ struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector);
+ clear_bit(BIO_UPTODATE, &bi->bi_flags);
+ if (--bi->bi_phys_segments == 0) {
+ md_write_end(conf->mddev);
+ bi->bi_next = return_bi;
+ return_bi = bi;
+ }
+ bi = bi2;
+ }
+
+ /* fail any reads if this device is non-operational */
+ if (!test_bit(R5_Insync, &sh->dev[i].flags)) {
+ bi = sh->dev[i].toread;
+ sh->dev[i].toread = NULL;
+ if (bi) to_read--;
+ while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS){
+ struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector);
+ clear_bit(BIO_UPTODATE, &bi->bi_flags);
+ if (--bi->bi_phys_segments == 0) {
+ bi->bi_next = return_bi;
+ return_bi = bi;
+ }
+ bi = nextbi;
+ }
+ }
+ }
+ spin_unlock_irq(&conf->device_lock);
+ }
+ if (failed > 2 && syncing) {
+ md_done_sync(conf->mddev, STRIPE_SECTORS,0);
+ clear_bit(STRIPE_SYNCING, &sh->state);
+ syncing = 0;
+ }
+
+ /*
+ * might be able to return some write requests if the parity blocks
+ * are safe, or on a failed drive
+ */
+ pdev = &sh->dev[pd_idx];
+ p_failed = (failed >= 1 && failed_num[0] == pd_idx)
+ || (failed >= 2 && failed_num[1] == pd_idx);
+ qdev = &sh->dev[qd_idx];
+ q_failed = (failed >= 1 && failed_num[0] == qd_idx)
+ || (failed >= 2 && failed_num[1] == qd_idx);
+
+ if ( written &&
+ ( p_failed || ((test_bit(R5_Insync, &pdev->flags)
+ && !test_bit(R5_LOCKED, &pdev->flags)
+ && test_bit(R5_UPTODATE, &pdev->flags))) ) &&
+ ( q_failed || ((test_bit(R5_Insync, &qdev->flags)
+ && !test_bit(R5_LOCKED, &qdev->flags)
+ && test_bit(R5_UPTODATE, &qdev->flags))) ) ) {
+ /* any written block on an uptodate or failed drive can be
+ * returned. Note that if we 'wrote' to a failed drive,
+ * it will be UPTODATE, but never LOCKED, so we don't need
+ * to test 'failed' directly.
+ */
+ for (i=disks; i--; )
+ if (sh->dev[i].written) {
+ dev = &sh->dev[i];
+ if (!test_bit(R5_LOCKED, &dev->flags) &&
+ test_bit(R5_UPTODATE, &dev->flags) ) {
+ /* We can return any write requests */
+ struct bio *wbi, *wbi2;
+ PRINTK("Return write for stripe %llu disc %d\n",
+ (unsigned long long)sh->sector, i);
+ spin_lock_irq(&conf->device_lock);
+ wbi = dev->written;
+ dev->written = NULL;
+ while (wbi && wbi->bi_sector < dev->sector + STRIPE_SECTORS) {
+ wbi2 = r5_next_bio(wbi, dev->sector);
+ if (--wbi->bi_phys_segments == 0) {
+ md_write_end(conf->mddev);
+ wbi->bi_next = return_bi;
+ return_bi = wbi;
+ }
+ wbi = wbi2;
+ }
+ spin_unlock_irq(&conf->device_lock);
+ }
+ }
+ }
+
+ /* Now we might consider reading some blocks, either to check/generate
+ * parity, or to satisfy requests
+ * or to load a block that is being partially written.
+ */
+ if (to_read || non_overwrite || (syncing && (uptodate+failed < disks))) {
+ for (i=disks; i--;) {
+ dev = &sh->dev[i];
+ if (!test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) &&
+ (dev->toread ||
+ (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) ||
+ syncing ||
+ (failed >= 1 && (sh->dev[failed_num[0]].toread ||
+ (sh->dev[failed_num[0]].towrite && !test_bit(R5_OVERWRITE, &sh->dev[failed_num[0]].flags)))) ||
+ (failed >= 2 && (sh->dev[failed_num[1]].toread ||
+ (sh->dev[failed_num[1]].towrite && !test_bit(R5_OVERWRITE, &sh->dev[failed_num[1]].flags))))
+ )
+ ) {
+ /* we would like to get this block, possibly
+ * by computing it, but we might not be able to
+ */
+ if (uptodate == disks-1) {
+ PRINTK("Computing stripe %llu block %d\n",
+ (unsigned long long)sh->sector, i);
+ compute_block_1(sh, i);
+ uptodate++;
+ } else if ( uptodate == disks-2 && failed >= 2 ) {
+ /* Computing 2-failure is *very* expensive; only do it if failed >= 2 */
+ int other;
+ for (other=disks; other--;) {
+ if ( other == i )
+ continue;
+ if ( !test_bit(R5_UPTODATE, &sh->dev[other].flags) )
+ break;
+ }
+ BUG_ON(other < 0);
+ PRINTK("Computing stripe %llu blocks %d,%d\n",
+ (unsigned long long)sh->sector, i, other);
+ compute_block_2(sh, i, other);
+ uptodate += 2;
+ } else if (test_bit(R5_Insync, &dev->flags)) {
+ set_bit(R5_LOCKED, &dev->flags);
+ set_bit(R5_Wantread, &dev->flags);
+#if 0
+ /* if I am just reading this block and we don't have
+ a failed drive, or any pending writes then sidestep the cache */
+ if (sh->bh_read[i] && !sh->bh_read[i]->b_reqnext &&
+ ! syncing && !failed && !to_write) {
+ sh->bh_cache[i]->b_page = sh->bh_read[i]->b_page;
+ sh->bh_cache[i]->b_data = sh->bh_read[i]->b_data;
+ }
+#endif
+ locked++;
+ PRINTK("Reading block %d (sync=%d)\n",
+ i, syncing);
+ if (syncing)
+ md_sync_acct(conf->disks[i].rdev, STRIPE_SECTORS);
+ }
+ }
+ }
+ set_bit(STRIPE_HANDLE, &sh->state);
+ }
+
+ /* now to consider writing and what else, if anything should be read */
+ if (to_write) {
+ int rcw=0, must_compute=0;
+ for (i=disks ; i--;) {
+ dev = &sh->dev[i];
+ /* Would I have to read this buffer for reconstruct_write */
+ if (!test_bit(R5_OVERWRITE, &dev->flags)
+ && i != pd_idx && i != qd_idx
+ && (!test_bit(R5_LOCKED, &dev->flags)
+#if 0
+ || sh->bh_page[i] != bh->b_page
+#endif
+ ) &&
+ !test_bit(R5_UPTODATE, &dev->flags)) {
+ if (test_bit(R5_Insync, &dev->flags)) rcw++;
+ else {
+ PRINTK("raid6: must_compute: disk %d flags=%#lx\n", i, dev->flags);
+ must_compute++;
+ }
+ }
+ }
+ PRINTK("for sector %llu, rcw=%d, must_compute=%d\n",
+ (unsigned long long)sh->sector, rcw, must_compute);
+ set_bit(STRIPE_HANDLE, &sh->state);
+
+ if (rcw > 0)
+ /* want reconstruct write, but need to get some data */
+ for (i=disks; i--;) {
+ dev = &sh->dev[i];
+ if (!test_bit(R5_OVERWRITE, &dev->flags)
+ && !(failed == 0 && (i == pd_idx || i == qd_idx))
+ && !test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) &&
+ test_bit(R5_Insync, &dev->flags)) {
+ if (test_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
+ {
+ PRINTK("Read_old stripe %llu block %d for Reconstruct\n",
+ (unsigned long long)sh->sector, i);
+ set_bit(R5_LOCKED, &dev->flags);
+ set_bit(R5_Wantread, &dev->flags);
+ locked++;
+ } else {
+ PRINTK("Request delayed stripe %llu block %d for Reconstruct\n",
+ (unsigned long long)sh->sector, i);
+ set_bit(STRIPE_DELAYED, &sh->state);
+ set_bit(STRIPE_HANDLE, &sh->state);
+ }
+ }
+ }
+ /* now if nothing is locked, and if we have enough data, we can start a write request */
+ if (locked == 0 && rcw == 0) {
+ if ( must_compute > 0 ) {
+ /* We have failed blocks and need to compute them */
+ switch ( failed ) {
+ case 0: BUG();
+ case 1: compute_block_1(sh, failed_num[0]); break;
+ case 2: compute_block_2(sh, failed_num[0], failed_num[1]); break;
+ default: BUG(); /* This request should have been failed? */
+ }
+ }
+
+ PRINTK("Computing parity for stripe %llu\n", (unsigned long long)sh->sector);
+ compute_parity(sh, RECONSTRUCT_WRITE);
+ /* now every locked buffer is ready to be written */
+ for (i=disks; i--;)
+ if (test_bit(R5_LOCKED, &sh->dev[i].flags)) {
+ PRINTK("Writing stripe %llu block %d\n",
+ (unsigned long long)sh->sector, i);
+ locked++;
+ set_bit(R5_Wantwrite, &sh->dev[i].flags);
+#if 0 /**** FIX: I don't understand the logic here... ****/
+ if (!test_bit(R5_Insync, &sh->dev[i].flags)
+ || ((i==pd_idx || i==qd_idx) && failed == 0)) /* FIX? */
+ set_bit(STRIPE_INSYNC, &sh->state);
+#endif
+ }
+ if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) {
+ atomic_dec(&conf->preread_active_stripes);
+ if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD)
+ md_wakeup_thread(conf->mddev->thread);
+ }
+ }
+ }
+
+ /* maybe we need to check and possibly fix the parity for this stripe
+ * Any reads will already have been scheduled, so we just see if enough data
+ * is available
+ */
+ if (syncing && locked == 0 &&
+ !test_bit(STRIPE_INSYNC, &sh->state) && failed <= 2) {
+ set_bit(STRIPE_HANDLE, &sh->state);
+#if 0 /* RAID-6: Don't support CHECK PARITY yet */
+ if (failed == 0) {
+ char *pagea;
+ if (uptodate != disks)
+ BUG();
+ compute_parity(sh, CHECK_PARITY);
+ uptodate--;
+ pagea = page_address(sh->dev[pd_idx].page);
+ if ((*(u32*)pagea) == 0 &&
+ !memcmp(pagea, pagea+4, STRIPE_SIZE-4)) {
+ /* parity is correct (on disc, not in buffer any more) */
+ set_bit(STRIPE_INSYNC, &sh->state);
+ }
+ }
+#endif
+ if (!test_bit(STRIPE_INSYNC, &sh->state)) {
+ int failed_needupdate[2];
+ struct r5dev *adev, *bdev;
+
+ if ( failed < 1 )
+ failed_num[0] = pd_idx;
+ if ( failed < 2 )
+ failed_num[1] = (failed_num[0] == qd_idx) ? pd_idx : qd_idx;
+
+ failed_needupdate[0] = !test_bit(R5_UPTODATE, &sh->dev[failed_num[0]].flags);
+ failed_needupdate[1] = !test_bit(R5_UPTODATE, &sh->dev[failed_num[1]].flags);
+
+ PRINTK("sync: failed=%d num=%d,%d fnu=%u%u\n",
+ failed, failed_num[0], failed_num[1], failed_needupdate[0], failed_needupdate[1]);
+
+#if 0 /* RAID-6: This code seems to require that CHECK_PARITY destroys the uptodateness of the parity */
+ /* should be able to compute the missing block(s) and write to spare */
+ if ( failed_needupdate[0] ^ failed_needupdate[1] ) {
+ if (uptodate+1 != disks)
+ BUG();
+ compute_block_1(sh, failed_needupdate[0] ? failed_num[0] : failed_num[1]);
+ uptodate++;
+ } else if ( failed_needupdate[0] & failed_needupdate[1] ) {
+ if (uptodate+2 != disks)
+ BUG();
+ compute_block_2(sh, failed_num[0], failed_num[1]);
+ uptodate += 2;
+ }
+#else
+ compute_block_2(sh, failed_num[0], failed_num[1]);
+ uptodate += failed_needupdate[0] + failed_needupdate[1];
+#endif
+
+ if (uptodate != disks)
+ BUG();
+
+ PRINTK("Marking for sync stripe %llu blocks %d,%d\n",
+ (unsigned long long)sh->sector, failed_num[0], failed_num[1]);
+
+ /**** FIX: Should we really do both of these unconditionally? ****/
+ adev = &sh->dev[failed_num[0]];
+ locked += !test_bit(R5_LOCKED, &adev->flags);
+ set_bit(R5_LOCKED, &adev->flags);
+ set_bit(R5_Wantwrite, &adev->flags);
+ bdev = &sh->dev[failed_num[1]];
+ locked += !test_bit(R5_LOCKED, &bdev->flags);
+ set_bit(R5_LOCKED, &bdev->flags);
+ set_bit(R5_Wantwrite, &bdev->flags);
+
+ set_bit(STRIPE_INSYNC, &sh->state);
+ set_bit(R5_Syncio, &adev->flags);
+ set_bit(R5_Syncio, &bdev->flags);
+ }
+ }
+ if (syncing && locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) {
+ md_done_sync(conf->mddev, STRIPE_SECTORS,1);
+ clear_bit(STRIPE_SYNCING, &sh->state);
+ }
+
+ spin_unlock(&sh->lock);
+
+ while ((bi=return_bi)) {
+ int bytes = bi->bi_size;
+
+ return_bi = bi->bi_next;
+ bi->bi_next = NULL;
+ bi->bi_size = 0;
+ bi->bi_end_io(bi, bytes, 0);
+ }
+ for (i=disks; i-- ;) {
+ int rw;
+ struct bio *bi;
+ mdk_rdev_t *rdev;
+ if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags))
+ rw = 1;
+ else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags))
+ rw = 0;
+ else
+ continue;
+
+ bi = &sh->dev[i].req;
+
+ bi->bi_rw = rw;
+ if (rw)
+ bi->bi_end_io = raid6_end_write_request;
+ else
+ bi->bi_end_io = raid6_end_read_request;
+
+ spin_lock_irq(&conf->device_lock);
+ rdev = conf->disks[i].rdev;
+ if (rdev && rdev->faulty)
+ rdev = NULL;
+ if (rdev)
+ atomic_inc(&rdev->nr_pending);
+ spin_unlock_irq(&conf->device_lock);
+
+ if (rdev) {
+ if (test_bit(R5_Syncio, &sh->dev[i].flags))
+ md_sync_acct(rdev, STRIPE_SECTORS);
+
+ bi->bi_bdev = rdev->bdev;
+ PRINTK("for %llu schedule op %ld on disc %d\n",
+ (unsigned long long)sh->sector, bi->bi_rw, i);
+ atomic_inc(&sh->count);
+ bi->bi_sector = sh->sector + rdev->data_offset;
+ bi->bi_flags = 1 << BIO_UPTODATE;
+ bi->bi_vcnt = 1;
+ bi->bi_idx = 0;
+ bi->bi_io_vec = &sh->dev[i].vec;
+ bi->bi_io_vec[0].bv_len = STRIPE_SIZE;
+ bi->bi_io_vec[0].bv_offset = 0;
+ bi->bi_size = STRIPE_SIZE;
+ bi->bi_next = NULL;
+ generic_make_request(bi);
+ } else {
+ PRINTK("skip op %ld on disc %d for sector %llu\n",
+ bi->bi_rw, i, (unsigned long long)sh->sector);
+ clear_bit(R5_LOCKED, &sh->dev[i].flags);
+ set_bit(STRIPE_HANDLE, &sh->state);
+ }
+ }
+}
+
+static inline void raid6_activate_delayed(raid6_conf_t *conf)
+{
+ if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) {
+ while (!list_empty(&conf->delayed_list)) {
+ struct list_head *l = conf->delayed_list.next;
+ struct stripe_head *sh;
+ sh = list_entry(l, struct stripe_head, lru);
+ list_del_init(l);
+ clear_bit(STRIPE_DELAYED, &sh->state);
+ if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
+ atomic_inc(&conf->preread_active_stripes);
+ list_add_tail(&sh->lru, &conf->handle_list);
+ }
+ }
+}
+static void raid6_unplug_device(void *data)
+{
+ request_queue_t *q = data;
+ mddev_t *mddev = q->queuedata;
+ raid6_conf_t *conf = mddev_to_conf(mddev);
+ unsigned long flags;
+
+ spin_lock_irqsave(&conf->device_lock, flags);
+
+ if (blk_remove_plug(q))
+ raid6_activate_delayed(conf);
+ md_wakeup_thread(mddev->thread);
+
+ spin_unlock_irqrestore(&conf->device_lock, flags);
+}
+
+static inline void raid6_plug_device(raid6_conf_t *conf)
+{
+ spin_lock_irq(&conf->device_lock);
+ blk_plug_device(conf->mddev->queue);
+ spin_unlock_irq(&conf->device_lock);
+}
+
+static int make_request (request_queue_t *q, struct bio * bi)
+{
+ mddev_t *mddev = q->queuedata;
+ raid6_conf_t *conf = mddev_to_conf(mddev);
+ const unsigned int raid_disks = conf->raid_disks;
+ const unsigned int data_disks = raid_disks - 2;
+ unsigned int dd_idx, pd_idx;
+ sector_t new_sector;
+ sector_t logical_sector, last_sector;
+ struct stripe_head *sh;
+
+ logical_sector = bi->bi_sector & ~(STRIPE_SECTORS-1);
+ last_sector = bi->bi_sector + (bi->bi_size>>9);
+
+ bi->bi_next = NULL;
+ bi->bi_phys_segments = 1; /* over-loaded to count active stripes */
+ if ( bio_data_dir(bi) == WRITE )
+ md_write_start(mddev);
+ for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) {
+
+ new_sector = raid6_compute_sector(logical_sector,
+ raid_disks, data_disks, &dd_idx, &pd_idx, conf);
+
+ PRINTK("raid6: make_request, sector %Lu logical %Lu\n",
+ (unsigned long long)new_sector,
+ (unsigned long long)logical_sector);
+
+ sh = get_active_stripe(conf, new_sector, pd_idx, (bi->bi_rw&RWA_MASK));
+ if (sh) {
+
+ add_stripe_bio(sh, bi, dd_idx, (bi->bi_rw&RW_MASK));
+
+ raid6_plug_device(conf);
+ handle_stripe(sh);
+ release_stripe(sh);
+ } else {
+ /* cannot get stripe for read-ahead, just give-up */
+ clear_bit(BIO_UPTODATE, &bi->bi_flags);
+ break;
+ }
+
+ }
+ spin_lock_irq(&conf->device_lock);
+ if (--bi->bi_phys_segments == 0) {
+ int bytes = bi->bi_size;
+
+ if ( bio_data_dir(bi) == WRITE )
+ md_write_end(mddev);
+ bi->bi_size = 0;
+ bi->bi_end_io(bi, bytes, 0);
+ }
+ spin_unlock_irq(&conf->device_lock);
+ return 0;
+}
+
+/* FIXME go_faster isn't used */
+static int sync_request (mddev_t *mddev, sector_t sector_nr, int go_faster)
+{
+ raid6_conf_t *conf = (raid6_conf_t *) mddev->private;
+ struct stripe_head *sh;
+ int sectors_per_chunk = conf->chunk_size >> 9;
+ sector_t x;
+ unsigned long stripe;
+ int chunk_offset;
+ int dd_idx, pd_idx;
+ unsigned long first_sector;
+ int raid_disks = conf->raid_disks;
+ int data_disks = raid_disks - 2;
+
+ if (sector_nr >= mddev->size <<1)
+ /* just being told to finish up .. nothing to do */
+ return 0;
+
+ x = sector_nr;
+ chunk_offset = sector_div(x, sectors_per_chunk);
+ stripe = x;
+ BUG_ON(x != stripe);
+
+ first_sector = raid6_compute_sector(stripe*data_disks*sectors_per_chunk
+ + chunk_offset, raid_disks, data_disks, &dd_idx, &pd_idx, conf);
+ sh = get_active_stripe(conf, sector_nr, pd_idx, 0);
+ spin_lock(&sh->lock);
+ set_bit(STRIPE_SYNCING, &sh->state);
+ clear_bit(STRIPE_INSYNC, &sh->state);
+ spin_unlock(&sh->lock);
+
+ handle_stripe(sh);
+ release_stripe(sh);
+
+ return STRIPE_SECTORS;
+}
+
+/*
+ * This is our raid6 kernel thread.
+ *
+ * We scan the hash table for stripes which can be handled now.
+ * During the scan, completed stripes are saved for us by the interrupt
+ * handler, so that they will not have to wait for our next wakeup.
+ */
+static void raid6d (mddev_t *mddev)
+{
+ struct stripe_head *sh;
+ raid6_conf_t *conf = mddev_to_conf(mddev);
+ int handled;
+
+ PRINTK("+++ raid6d active\n");
+
+ md_check_recovery(mddev);
+ md_handle_safemode(mddev);
+
+ handled = 0;
+ spin_lock_irq(&conf->device_lock);
+ while (1) {
+ struct list_head *first;
+
+ if (list_empty(&conf->handle_list) &&
+ atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD &&
+ !blk_queue_plugged(mddev->queue) &&
+ !list_empty(&conf->delayed_list))
+ raid6_activate_delayed(conf);
+
+ if (list_empty(&conf->handle_list))
+ break;
+
+ first = conf->handle_list.next;
+ sh = list_entry(first, struct stripe_head, lru);
+
+ list_del_init(first);
+ atomic_inc(&sh->count);
+ if (atomic_read(&sh->count)!= 1)
+ BUG();
+ spin_unlock_irq(&conf->device_lock);
+
+ handled++;
+ handle_stripe(sh);
+ release_stripe(sh);
+
+ spin_lock_irq(&conf->device_lock);
+ }
+ PRINTK("%d stripes handled\n", handled);
+
+ spin_unlock_irq(&conf->device_lock);
+
+ PRINTK("--- raid6d inactive\n");
+}
+
+static int run (mddev_t *mddev)
+{
+ raid6_conf_t *conf;
+ int raid_disk, memory;
+ mdk_rdev_t *rdev;
+ struct disk_info *disk;
+ struct list_head *tmp;
+
+ if (mddev->level != 6) {
+ PRINTK("raid6: md%d: raid level not set to 6 (%d)\n", mdidx(mddev), mddev->level);
+ return -EIO;
+ }
+
+ mddev->private = kmalloc (sizeof (raid6_conf_t)
+ + mddev->raid_disks * sizeof(struct disk_info),
+ GFP_KERNEL);
+ if ((conf = mddev->private) == NULL)
+ goto abort;
+ memset (conf, 0, sizeof (*conf) + mddev->raid_disks * sizeof(struct disk_info) );
+ conf->mddev = mddev;
+
+ if ((conf->stripe_hashtbl = (struct stripe_head **) __get_free_pages(GFP_ATOMIC, HASH_PAGES_ORDER)) == NULL)
+ goto abort;
+ memset(conf->stripe_hashtbl, 0, HASH_PAGES * PAGE_SIZE);
+
+ conf->device_lock = SPIN_LOCK_UNLOCKED;
+ init_waitqueue_head(&conf->wait_for_stripe);
+ INIT_LIST_HEAD(&conf->handle_list);
+ INIT_LIST_HEAD(&conf->delayed_list);
+ INIT_LIST_HEAD(&conf->inactive_list);
+ atomic_set(&conf->active_stripes, 0);
+ atomic_set(&conf->preread_active_stripes, 0);
+
+ mddev->queue->unplug_fn = raid6_unplug_device;
+
+ PRINTK("raid6: run(md%d) called.\n", mdidx(mddev));
+
+ ITERATE_RDEV(mddev,rdev,tmp) {
+ raid_disk = rdev->raid_disk;
+ if (raid_disk >= mddev->raid_disks
+ || raid_disk < 0)
+ continue;
+ disk = conf->disks + raid_disk;
+
+ disk->rdev = rdev;
+
+ if (rdev->in_sync) {
+ char b[BDEVNAME_SIZE];
+ printk(KERN_INFO "raid6: device %s operational as raid"
+ " disk %d\n", bdevname(rdev->bdev,b),
+ raid_disk);
+ conf->working_disks++;
+ }
+ }
+
+ conf->raid_disks = mddev->raid_disks;
+
+ /*
+ * 0 for a fully functional array, 1 or 2 for a degraded array.
+ */
+ mddev->degraded = conf->failed_disks = conf->raid_disks - conf->working_disks;
+ conf->mddev = mddev;
+ conf->chunk_size = mddev->chunk_size;
+ conf->level = mddev->level;
+ conf->algorithm = mddev->layout;
+ conf->max_nr_stripes = NR_STRIPES;
+
+ if (conf->raid_disks < 4) {
+ printk(KERN_ERR "raid6: not enough configured devices for md%d (%d, minimum 4)\n",
+ mdidx(mddev), conf->raid_disks);
+ goto abort;
+ }
+ if (!conf->chunk_size || conf->chunk_size % 4) {
+ printk(KERN_ERR "raid6: invalid chunk size %d for md%d\n",
+ conf->chunk_size, mdidx(mddev));
+ goto abort;
+ }
+ if (conf->algorithm > ALGORITHM_RIGHT_SYMMETRIC) {
+ printk(KERN_ERR
+ "raid6: unsupported parity algorithm %d for md%d\n",
+ conf->algorithm, mdidx(mddev));
+ goto abort;
+ }
+ if (mddev->degraded > 2) {
+ printk(KERN_ERR "raid6: not enough operational devices for md%d"
+ " (%d/%d failed)\n",
+ mdidx(mddev), conf->failed_disks, conf->raid_disks);
+ goto abort;
+ }
+
+#if 0 /* FIX: For now */
+ if (mddev->degraded > 0 &&
+ mddev->recovery_cp != MaxSector) {
+ printk(KERN_ERR "raid6: cannot start dirty degraded array for md%d\n", mdidx(mddev));
+ goto abort;
+ }
+#endif
+
+ {
+ mddev->thread = md_register_thread(raid6d, mddev, "md%d_raid6");
+ if (!mddev->thread) {
+ printk(KERN_ERR
+ "raid6: couldn't allocate thread for md%d\n",
+ mdidx(mddev));
+ goto abort;
+ }
+ }
+
+ memory = conf->max_nr_stripes * (sizeof(struct stripe_head) +
+ conf->raid_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024;
+ if (grow_stripes(conf, conf->max_nr_stripes)) {
+ printk(KERN_ERR
+ "raid6: couldn't allocate %dkB for buffers\n", memory);
+ shrink_stripes(conf);
+ md_unregister_thread(mddev->thread);
+ goto abort;
+ } else
+ printk(KERN_INFO "raid6: allocated %dkB for md%d\n",
+ memory, mdidx(mddev));
+
+ if (mddev->degraded == 0)
+ printk(KERN_INFO "raid6: raid level %d set md%d active with %d out of %d"
+ " devices, algorithm %d\n", conf->level, mdidx(mddev),
+ mddev->raid_disks-mddev->degraded, mddev->raid_disks,
+ conf->algorithm);
+ else
+ printk(KERN_ALERT "raid6: raid level %d set md%d active with %d"
+ " out of %d devices, algorithm %d\n", conf->level,
+ mdidx(mddev), mddev->raid_disks - mddev->degraded,
+ mddev->raid_disks, conf->algorithm);
+
+ print_raid6_conf(conf);
+
+ /* Ok, everything is just fine now */
+ mddev->array_size = mddev->size * (mddev->raid_disks - 2);
+ return 0;
+abort:
+ if (conf) {
+ print_raid6_conf(conf);
+ if (conf->stripe_hashtbl)
+ free_pages((unsigned long) conf->stripe_hashtbl,
+ HASH_PAGES_ORDER);
+ kfree(conf);
+ }
+ mddev->private = NULL;
+ printk(KERN_ALERT "raid6: failed to run raid set md%d\n", mdidx(mddev));
+ return -EIO;
+}
+
+
+
+static int stop (mddev_t *mddev)
+{
+ raid6_conf_t *conf = (raid6_conf_t *) mddev->private;
+
+ md_unregister_thread(mddev->thread);
+ mddev->thread = NULL;
+ shrink_stripes(conf);
+ free_pages((unsigned long) conf->stripe_hashtbl, HASH_PAGES_ORDER);
+ kfree(conf);
+ mddev->private = NULL;
+ return 0;
+}
+
+#if RAID6_DUMPSTATE
+static void print_sh (struct seq_file *seq, struct stripe_head *sh)
+{
+ int i;
+
+ seq_printf(seq, "sh %llu, pd_idx %d, state %ld.\n",
+ (unsigned long long)sh->sector, sh->pd_idx, sh->state);
+ seq_printf(seq, "sh %llu, count %d.\n",
+ (unsigned long long)sh->sector, atomic_read(&sh->count));
+ seq_printf(seq, "sh %llu, ", (unsigned long long)sh->sector);
+ for (i = 0; i < sh->raid_conf->raid_disks; i++) {
+ seq_printf(seq, "(cache%d: %p %ld) ",
+ i, sh->dev[i].page, sh->dev[i].flags);
+ }
+ seq_printf(seq, "\n");
+}
+
+static void printall (struct seq_file *seq, raid6_conf_t *conf)
+{
+ struct stripe_head *sh;
+ int i;
+
+ spin_lock_irq(&conf->device_lock);
+ for (i = 0; i < NR_HASH; i++) {
+ sh = conf->stripe_hashtbl[i];
+ for (; sh; sh = sh->hash_next) {
+ if (sh->raid_conf != conf)
+ continue;
+ print_sh(seq, sh);
+ }
+ }
+ spin_unlock_irq(&conf->device_lock);
+}
+#endif
+
+static void status (struct seq_file *seq, mddev_t *mddev)
+{
+ raid6_conf_t *conf = (raid6_conf_t *) mddev->private;
+ int i;
+
+ seq_printf (seq, " level %d, %dk chunk, algorithm %d", mddev->level, mddev->chunk_size >> 10, mddev->layout);
+ seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->working_disks);
+ for (i = 0; i < conf->raid_disks; i++)
+ seq_printf (seq, "%s",
+ conf->disks[i].rdev &&
+ conf->disks[i].rdev->in_sync ? "U" : "_");
+ seq_printf (seq, "]");
+#if RAID6_DUMPSTATE
+ seq_printf (seq, "\n");
+ printall(seq, conf);
+#endif
+}
+
+static void print_raid6_conf (raid6_conf_t *conf)
+{
+ int i;
+ struct disk_info *tmp;
+
+ printk("RAID6 conf printout:\n");
+ if (!conf) {
+ printk("(conf==NULL)\n");
+ return;
+ }
+ printk(" --- rd:%d wd:%d fd:%d\n", conf->raid_disks,
+ conf->working_disks, conf->failed_disks);
+
+ for (i = 0; i < conf->raid_disks; i++) {
+ char b[BDEVNAME_SIZE];
+ tmp = conf->disks + i;
+ if (tmp->rdev)
+ printk(" disk %d, o:%d, dev:%s\n",
+ i, !tmp->rdev->faulty,
+ bdevname(tmp->rdev->bdev,b));
+ }
+}
+
+static int raid6_spare_active(mddev_t *mddev)
+{
+ int i;
+ raid6_conf_t *conf = mddev->private;
+ struct disk_info *tmp;
+
+ spin_lock_irq(&conf->device_lock);
+ for (i = 0; i < conf->raid_disks; i++) {
+ tmp = conf->disks + i;
+ if (tmp->rdev
+ && !tmp->rdev->faulty
+ && !tmp->rdev->in_sync) {
+ mddev->degraded--;
+ conf->failed_disks--;
+ conf->working_disks++;
+ tmp->rdev->in_sync = 1;
+ }
+ }
+ spin_unlock_irq(&conf->device_lock);
+ print_raid6_conf(conf);
+ return 0;
+}
+
+static int raid6_remove_disk(mddev_t *mddev, int number)
+{
+ raid6_conf_t *conf = mddev->private;
+ int err = 1;
+ struct disk_info *p = conf->disks + number;
+
+ print_raid6_conf(conf);
+ spin_lock_irq(&conf->device_lock);
+
+ if (p->rdev) {
+ if (p->rdev->in_sync ||
+ atomic_read(&p->rdev->nr_pending)) {
+ err = -EBUSY;
+ goto abort;
+ }
+ p->rdev = NULL;
+ err = 0;
+ }
+ if (err)
+ MD_BUG();
+abort:
+ spin_unlock_irq(&conf->device_lock);
+ print_raid6_conf(conf);
+ return err;
+}
+
+static int raid6_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
+{
+ raid6_conf_t *conf = mddev->private;
+ int found = 0;
+ int disk;
+ struct disk_info *p;
+
+ spin_lock_irq(&conf->device_lock);
+ /*
+ * find the disk ...
+ */
+ for (disk=0; disk < mddev->raid_disks; disk++)
+ if ((p=conf->disks + disk)->rdev == NULL) {
+ p->rdev = rdev;
+ rdev->in_sync = 0;
+ rdev->raid_disk = disk;
+ found = 1;
+ break;
+ }
+ spin_unlock_irq(&conf->device_lock);
+ print_raid6_conf(conf);
+ return found;
+}
+
+static mdk_personality_t raid6_personality=
+{
+ .name = "raid6",
+ .owner = THIS_MODULE,
+ .make_request = make_request,
+ .run = run,
+ .stop = stop,
+ .status = status,
+ .error_handler = error,
+ .hot_add_disk = raid6_add_disk,
+ .hot_remove_disk= raid6_remove_disk,
+ .spare_active = raid6_spare_active,
+ .sync_request = sync_request,
+};
+
+static int __init raid6_init (void)
+{
+ int e;
+
+ e = raid6_select_algo();
+ if ( e )
+ return e;
+
+ return register_md_personality (RAID6, &raid6_personality);
+}
+
+static void raid6_exit (void)
+{
+ unregister_md_personality (RAID6);
+}
+
+module_init(raid6_init);
+module_exit(raid6_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("md-personality-8"); /* RAID6 */
diff -puN /dev/null drivers/md/raid6mmx.c
--- /dev/null 2002-08-30 16:31:37.000000000 -0700
+++ 25-akpm/drivers/md/raid6mmx.c 2004-01-07 22:20:04.000000000 -0800
@@ -0,0 +1,150 @@
+/* -*- 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,
+ * Bostom MA 02111-1307, USA; either version 2 of the License, or
+ * (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * raid6mmx.c
+ *
+ * MMX implementation of RAID-6 syndrome functions
+ */
+
+#if defined(__i386__) || defined(__x86_64__)
+
+#include "raid6.h"
+#include "raid6x86.h"
+
+/* Shared with raid6sse1.c */
+const struct raid6_mmx_constants {
+ u64 x1d;
+} raid6_mmx_constants = {
+ 0x1d1d1d1d1d1d1d1dULL,
+};
+
+static int raid6_have_mmx(void)
+{
+#ifdef __KERNEL__
+ /* Not really "boot_cpu" but "all_cpus" */
+ return boot_cpu_has(X86_FEATURE_MMX);
+#else
+ /* User space test code */
+ u32 features = cpuid_features();
+ return ( (features & (1<<23)) == (1<<23) );
+#endif
+}
+
+/*
+ * Plain MMX implementation
+ */
+static void raid6_mmx1_gen_syndrome(int disks, size_t bytes, void **ptrs)
+{
+ u8 **dptr = (u8 **)ptrs;
+ u8 *p, *q;
+ int d, z, z0;
+ raid6_mmx_save_t sa;
+
+ z0 = disks - 3; /* Highest data disk */
+ p = dptr[z0+1]; /* XOR parity */
+ q = dptr[z0+2]; /* RS syndrome */
+
+ raid6_before_mmx(&sa);
+
+ asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d));
+ asm volatile("pxor %mm5,%mm5"); /* Zero temp */
+
+ for ( d = 0 ; d < bytes ; d += 8 ) {
+ asm volatile("movq %0,%%mm2" : : "m" (dptr[z0][d])); /* P[0] */
+ asm volatile("movq %mm2,%mm4"); /* Q[0] */
+ for ( z = z0-1 ; z >= 0 ; z-- ) {
+ asm volatile("movq %0,%%mm6" : : "m" (dptr[z][d]));
+ asm volatile("pcmpgtb %mm4,%mm5");
+ asm volatile("paddb %mm4,%mm4");
+ asm volatile("pand %mm0,%mm5");
+ asm volatile("pxor %mm5,%mm4");
+ asm volatile("pxor %mm5,%mm5");
+ asm volatile("pxor %mm6,%mm2");
+ asm volatile("pxor %mm6,%mm4");
+ }
+ asm volatile("movq %%mm2,%0" : "=m" (p[d]));
+ asm volatile("pxor %mm2,%mm2");
+ asm volatile("movq %%mm4,%0" : "=m" (q[d]));
+ asm volatile("pxor %mm4,%mm4");
+ }
+
+ raid6_after_mmx(&sa);
+}
+
+const struct raid6_calls raid6_mmxx1 = {
+ raid6_mmx1_gen_syndrome,
+ raid6_have_mmx,
+ "mmxx1",
+ 0
+};
+
+/*
+ * Unrolled-by-2 MMX implementation
+ */
+static void raid6_mmx2_gen_syndrome(int disks, size_t bytes, void **ptrs)
+{
+ u8 **dptr = (u8 **)ptrs;
+ u8 *p, *q;
+ int d, z, z0;
+ raid6_mmx_save_t sa;
+
+ z0 = disks - 3; /* Highest data disk */
+ p = dptr[z0+1]; /* XOR parity */
+ q = dptr[z0+2]; /* RS syndrome */
+
+ raid6_before_mmx(&sa);
+
+ asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d));
+ asm volatile("pxor %mm5,%mm5"); /* Zero temp */
+ asm volatile("pxor %mm7,%mm7"); /* Zero temp */
+
+ for ( d = 0 ; d < bytes ; d += 16 ) {
+ asm volatile("movq %0,%%mm2" : : "m" (dptr[z0][d])); /* P[0] */
+ asm volatile("movq %0,%%mm3" : : "m" (dptr[z0][d+8]));
+ asm volatile("movq %mm2,%mm4"); /* Q[0] */
+ asm volatile("movq %mm3,%mm6"); /* Q[1] */
+ for ( z = z0-1 ; z >= 0 ; z-- ) {
+ asm volatile("pcmpgtb %mm4,%mm5");
+ asm volatile("pcmpgtb %mm6,%mm7");
+ asm volatile("paddb %mm4,%mm4");
+ asm volatile("paddb %mm6,%mm6");
+ asm volatile("pand %mm0,%mm5");
+ asm volatile("pand %mm0,%mm7");
+ asm volatile("pxor %mm5,%mm4");
+ asm volatile("pxor %mm7,%mm6");
+ asm volatile("movq %0,%%mm5" : : "m" (dptr[z][d]));
+ asm volatile("movq %0,%%mm7" : : "m" (dptr[z][d+8]));
+ asm volatile("pxor %mm5,%mm2");
+ asm volatile("pxor %mm7,%mm3");
+ asm volatile("pxor %mm5,%mm4");
+ asm volatile("pxor %mm7,%mm6");
+ asm volatile("pxor %mm5,%mm5");
+ asm volatile("pxor %mm7,%mm7");
+ }
+ asm volatile("movq %%mm2,%0" : "=m" (p[d]));
+ asm volatile("movq %%mm3,%0" : "=m" (p[d+8]));
+ asm volatile("movq %%mm4,%0" : "=m" (q[d]));
+ asm volatile("movq %%mm6,%0" : "=m" (q[d+8]));
+ }
+
+ raid6_after_mmx(&sa);
+}
+
+const struct raid6_calls raid6_mmxx2 = {
+ raid6_mmx2_gen_syndrome,
+ raid6_have_mmx,
+ "mmxx2",
+ 0
+};
+
+#endif
diff -puN /dev/null drivers/md/raid6recov.c
--- /dev/null 2002-08-30 16:31:37.000000000 -0700
+++ 25-akpm/drivers/md/raid6recov.c 2004-01-07 22:20:04.000000000 -0800
@@ -0,0 +1,133 @@
+/* -*- 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,
+ * Bostom MA 02111-1307, USA; either version 2 of the License, or
+ * (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * raid6recov.c
+ *
+ * RAID-6 data recovery in dual failure mode. In single failure mode,
+ * use the RAID-5 algorithm (or, in the case of Q failure, just reconstruct
+ * the syndrome.)
+ */
+
+#include "raid6.h"
+
+/* Recover two failed data blocks. */
+void raid6_2data_recov(int disks, size_t bytes, int faila, int failb,
+ void **ptrs)
+{
+ u8 *p, *q, *dp, *dq;
+ u8 px, qx, db;
+ const u8 *pbmul; /* P multiplier table for B data */
+ const u8 *qmul; /* Q multiplier table (for both) */
+
+ p = (u8 *)ptrs[disks-2];
+ q = (u8 *)ptrs[disks-1];
+
+ /* Compute syndrome with zero for the missing data pages
+ Use the dead data pages as temporary storage for
+ delta p and delta q */
+ dp = (u8 *)ptrs[faila];
+ ptrs[faila] = (void *)raid6_empty_zero_page;
+ ptrs[disks-2] = dp;
+ dq = (u8 *)ptrs[failb];
+ ptrs[failb] = (void *)raid6_empty_zero_page;
+ ptrs[disks-1] = dq;
+
+ raid6_call.gen_syndrome(disks, bytes, ptrs);
+
+ /* Restore pointer table */
+ ptrs[faila] = dp;
+ ptrs[failb] = dq;
+ ptrs[disks-2] = p;
+ ptrs[disks-1] = q;
+
+ /* Now, pick the proper data tables */
+ pbmul = raid6_gfmul[raid6_gfexi[failb-faila]];
+ qmul = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]];
+
+ /* Now do it... */
+ while ( bytes-- ) {
+ px = *p ^ *dp;
+ qx = qmul[*q ^ *dq];
+ *dq++ = db = pbmul[px] ^ qx; /* Reconstructed B */
+ *dp++ = db ^ px; /* Reconstructed A */
+ p++; q++;
+ }
+}
+
+
+
+
+/* Recover failure of one data block plus the P block */
+void raid6_datap_recov(int disks, size_t bytes, int faila, void **ptrs)
+{
+ u8 *p, *q, *dq;
+ const u8 *qmul; /* Q multiplier table */
+
+ p = (u8 *)ptrs[disks-2];
+ q = (u8 *)ptrs[disks-1];
+
+ /* Compute syndrome with zero for the missing data page
+ Use the dead data page as temporary storage for delta q */
+ dq = (u8 *)ptrs[faila];
+ ptrs[faila] = (void *)raid6_empty_zero_page;
+ ptrs[disks-1] = dq;
+
+ raid6_call.gen_syndrome(disks, bytes, ptrs);
+
+ /* Restore pointer table */
+ ptrs[faila] = dq;
+ ptrs[disks-1] = q;
+
+ /* Now, pick the proper data tables */
+ qmul = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]]];
+
+ /* Now do it... */
+ while ( bytes-- ) {
+ *p++ ^= *dq = qmul[*q ^ *dq];
+ q++; dq++;
+ }
+}
+
+
+#ifndef __KERNEL__ /* Testing only */
+
+/* Recover two failed blocks. */
+void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, void **ptrs)
+{
+ if ( faila > failb ) {
+ int tmp = faila;
+ faila = failb;
+ failb = tmp;
+ }
+
+ if ( failb == disks-1 ) {
+ if ( faila == disks-2 ) {
+ /* P+Q failure. Just rebuild the syndrome. */
+ raid6_call.gen_syndrome(disks, bytes, ptrs);
+ } else {
+ /* data+Q failure. Reconstruct data from P,
+ then rebuild syndrome. */
+ /* FIX */
+ }
+ } else {
+ if ( failb == disks-2 ) {
+ /* data+P failure. */
+ raid6_datap_recov(disks, bytes, faila, ptrs);
+ } else {
+ /* data+data failure. */
+ raid6_2data_recov(disks, bytes, faila, failb, ptrs);
+ }
+ }
+}
+
+#endif
diff -puN /dev/null drivers/md/raid6sse1.c
--- /dev/null 2002-08-30 16:31:37.000000000 -0700
+++ 25-akpm/drivers/md/raid6sse1.c 2004-01-07 22:20:04.000000000 -0800
@@ -0,0 +1,171 @@
+/* -*- 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,
+ * Bostom MA 02111-1307, USA; either version 2 of the License, or
+ * (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * raid6sse1.c
+ *
+ * SSE-1/MMXEXT implementation of RAID-6 syndrome functions
+ *
+ * This is really an MMX implementation, but it requires SSE-1 or
+ * AMD MMXEXT for prefetch support and a few other features. The
+ * support for nontemporal memory accesses is enough to make this
+ * worthwhile as a separate implementation.
+ */
+
+#if defined(__i386__) || defined(__x86_64__)
+
+#include "raid6.h"
+#include "raid6x86.h"
+
+/* Defined in raid6mmx.c */
+extern const struct raid6_mmx_constants {
+ u64 x1d;
+} raid6_mmx_constants;
+
+static int raid6_have_sse1_or_mmxext(void)
+{
+#ifdef __KERNEL__
+ /* Not really boot_cpu but "all_cpus" */
+ return boot_cpu_has(X86_FEATURE_MMX) &&
+ (boot_cpu_has(X86_FEATURE_XMM) ||
+ boot_cpu_has(X86_FEATURE_MMXEXT));
+#else
+ /* User space test code - this incorrectly breaks on some Athlons */
+ u32 features = cpuid_features();
+ return ( (features & (5<<23)) == (5<<23) );
+#endif
+}
+
+/*
+ * Plain SSE1 implementation
+ */
+static void raid6_sse11_gen_syndrome(int disks, size_t bytes, void **ptrs)
+{
+ u8 **dptr = (u8 **)ptrs;
+ u8 *p, *q;
+ int d, z, z0;
+ raid6_mmx_save_t sa;
+
+ z0 = disks - 3; /* Highest data disk */
+ p = dptr[z0+1]; /* XOR parity */
+ q = dptr[z0+2]; /* RS syndrome */
+
+ /* This is really MMX code, not SSE */
+ raid6_before_mmx(&sa);
+
+ asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d));
+ asm volatile("pxor %mm5,%mm5"); /* Zero temp */
+
+ for ( d = 0 ; d < bytes ; d += 8 ) {
+ asm volatile("prefetchnta %0" : : "m" (dptr[z0][d]));
+ asm volatile("movq %0,%%mm2" : : "m" (dptr[z0][d])); /* P[0] */
+ asm volatile("prefetchnta %0" : : "m" (dptr[z0-1][d]));
+ asm volatile("movq %mm2,%mm4"); /* Q[0] */
+ asm volatile("movq %0,%%mm6" : : "m" (dptr[z0-1][d]));
+ for ( z = z0-2 ; z >= 0 ; z-- ) {
+ asm volatile("prefetchnta %0" : : "m" (dptr[z][d]));
+ asm volatile("pcmpgtb %mm4,%mm5");
+ asm volatile("paddb %mm4,%mm4");
+ asm volatile("pand %mm0,%mm5");
+ asm volatile("pxor %mm5,%mm4");
+ asm volatile("pxor %mm5,%mm5");
+ asm volatile("pxor %mm6,%mm2");
+ asm volatile("pxor %mm6,%mm4");
+ asm volatile("movq %0,%%mm6" : : "m" (dptr[z][d]));
+ }
+ asm volatile("pcmpgtb %mm4,%mm5");
+ asm volatile("paddb %mm4,%mm4");
+ asm volatile("pand %mm0,%mm5");
+ asm volatile("pxor %mm5,%mm4");
+ asm volatile("pxor %mm5,%mm5");
+ asm volatile("pxor %mm6,%mm2");
+ asm volatile("pxor %mm6,%mm4");
+
+ asm volatile("movntq %%mm2,%0" : "=m" (p[d]));
+ asm volatile("movntq %%mm4,%0" : "=m" (q[d]));
+ }
+
+ raid6_after_mmx(&sa);
+ asm volatile("sfence" : : : "memory");
+}
+
+const struct raid6_calls raid6_sse1x1 = {
+ raid6_sse11_gen_syndrome,
+ raid6_have_sse1_or_mmxext,
+ "sse1x1",
+ 1 /* Has cache hints */
+};
+
+/*
+ * Unrolled-by-2 SSE1 implementation
+ */
+static void raid6_sse12_gen_syndrome(int disks, size_t bytes, void **ptrs)
+{
+ u8 **dptr = (u8 **)ptrs;
+ u8 *p, *q;
+ int d, z, z0;
+ raid6_mmx_save_t sa;
+
+ z0 = disks - 3; /* Highest data disk */
+ p = dptr[z0+1]; /* XOR parity */
+ q = dptr[z0+2]; /* RS syndrome */
+
+ raid6_before_mmx(&sa);
+
+ asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d));
+ asm volatile("pxor %mm5,%mm5"); /* Zero temp */
+ asm volatile("pxor %mm7,%mm7"); /* Zero temp */
+
+ /* We uniformly assume a single prefetch covers at least 16 bytes */
+ for ( d = 0 ; d < bytes ; d += 16 ) {
+ asm volatile("prefetchnta %0" : : "m" (dptr[z0][d]));
+ asm volatile("movq %0,%%mm2" : : "m" (dptr[z0][d])); /* P[0] */
+ asm volatile("movq %0,%%mm3" : : "m" (dptr[z0][d+8])); /* P[1] */
+ asm volatile("movq %mm2,%mm4"); /* Q[0] */
+ asm volatile("movq %mm3,%mm6"); /* Q[1] */
+ for ( z = z0-1 ; z >= 0 ; z-- ) {
+ asm volatile("prefetchnta %0" : : "m" (dptr[z][d]));
+ asm volatile("pcmpgtb %mm4,%mm5");
+ asm volatile("pcmpgtb %mm6,%mm7");
+ asm volatile("paddb %mm4,%mm4");
+ asm volatile("paddb %mm6,%mm6");
+ asm volatile("pand %mm0,%mm5");
+ asm volatile("pand %mm0,%mm7");
+ asm volatile("pxor %mm5,%mm4");
+ asm volatile("pxor %mm7,%mm6");
+ asm volatile("movq %0,%%mm5" : : "m" (dptr[z][d]));
+ asm volatile("movq %0,%%mm7" : : "m" (dptr[z][d+8]));
+ asm volatile("pxor %mm5,%mm2");
+ asm volatile("pxor %mm7,%mm3");
+ asm volatile("pxor %mm5,%mm4");
+ asm volatile("pxor %mm7,%mm6");
+ asm volatile("pxor %mm5,%mm5");
+ asm volatile("pxor %mm7,%mm7");
+ }
+ asm volatile("movntq %%mm2,%0" : "=m" (p[d]));
+ asm volatile("movntq %%mm3,%0" : "=m" (p[d+8]));
+ asm volatile("movntq %%mm4,%0" : "=m" (q[d]));
+ asm volatile("movntq %%mm6,%0" : "=m" (q[d+8]));
+ }
+
+ raid6_after_mmx(&sa);
+ asm volatile("sfence" : :: "memory");
+}
+
+const struct raid6_calls raid6_sse1x2 = {
+ raid6_sse12_gen_syndrome,
+ raid6_have_sse1_or_mmxext,
+ "sse1x2",
+ 1 /* Has cache hints */
+};
+
+#endif
diff -puN /dev/null drivers/md/raid6sse2.c
--- /dev/null 2002-08-30 16:31:37.000000000 -0700
+++ 25-akpm/drivers/md/raid6sse2.c 2004-01-07 22:20:04.000000000 -0800
@@ -0,0 +1,270 @@
+/* -*- 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,
+ * Bostom MA 02111-1307, USA; either version 2 of the License, or
+ * (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * raid6sse2.c
+ *
+ * SSE-2 implementation of RAID-6 syndrome functions
+ *
+ */
+
+#if defined(__i386__) || defined(__x86_64__)
+
+#include "raid6.h"
+#include "raid6x86.h"
+
+static const struct raid6_sse_constants {
+ u64 x1d[2];
+} raid6_sse_constants __attribute__((aligned(16))) = {
+ { 0x1d1d1d1d1d1d1d1dULL, 0x1d1d1d1d1d1d1d1dULL },
+};
+
+static int raid6_have_sse2(void)
+{
+#ifdef __KERNEL__
+ /* Not really boot_cpu but "all_cpus" */
+ return boot_cpu_has(X86_FEATURE_MMX) &&
+ boot_cpu_has(X86_FEATURE_FXSR) &&
+ boot_cpu_has(X86_FEATURE_XMM) &&
+ boot_cpu_has(X86_FEATURE_XMM2);
+#else
+ /* User space test code */
+ u32 features = cpuid_features();
+ return ( (features & (15<<23)) == (15<<23) );
+#endif
+}
+
+/*
+ * Plain SSE2 implementation
+ */
+static void raid6_sse21_gen_syndrome(int disks, size_t bytes, void **ptrs)
+{
+ u8 **dptr = (u8 **)ptrs;
+ u8 *p, *q;
+ int d, z, z0;
+ raid6_sse_save_t sa;
+
+ z0 = disks - 3; /* Highest data disk */
+ p = dptr[z0+1]; /* XOR parity */
+ q = dptr[z0+2]; /* RS syndrome */
+
+ raid6_before_sse2(&sa);
+
+ asm volatile("movdqa %0,%%xmm0" : : "m" (raid6_sse_constants.x1d[0]));
+ asm volatile("pxor %xmm5,%xmm5"); /* Zero temp */
+
+ for ( d = 0 ; d < bytes ; d += 16 ) {
+ asm volatile("prefetchnta %0" : : "m" (dptr[z0][d]));
+ asm volatile("movdqa %0,%%xmm2" : : "m" (dptr[z0][d])); /* P[0] */
+ asm volatile("prefetchnta %0" : : "m" (dptr[z0-1][d]));
+ asm volatile("movdqa %xmm2,%xmm4"); /* Q[0] */
+ asm volatile("movdqa %0,%%xmm6" : : "m" (dptr[z0-1][d]));
+ for ( z = z0-2 ; z >= 0 ; z-- ) {
+ asm volatile("prefetchnta %0" : : "m" (dptr[z][d]));
+ asm volatile("pcmpgtb %xmm4,%xmm5");
+ asm volatile("paddb %xmm4,%xmm4");
+ asm volatile("pand %xmm0,%xmm5");
+ asm volatile("pxor %xmm5,%xmm4");
+ asm volatile("pxor %xmm5,%xmm5");
+ asm volatile("pxor %xmm6,%xmm2");
+ asm volatile("pxor %xmm6,%xmm4");
+ asm volatile("movdqa %0,%%xmm6" : : "m" (dptr[z][d]));
+ }
+ asm volatile("pcmpgtb %xmm4,%xmm5");
+ asm volatile("paddb %xmm4,%xmm4");
+ asm volatile("pand %xmm0,%xmm5");
+ asm volatile("pxor %xmm5,%xmm4");
+ asm volatile("pxor %xmm5,%xmm5");
+ asm volatile("pxor %xmm6,%xmm2");
+ asm volatile("pxor %xmm6,%xmm4");
+
+ asm volatile("movntdq %%xmm2,%0" : "=m" (p[d]));
+ asm volatile("pxor %xmm2,%xmm2");
+ asm volatile("movntdq %%xmm4,%0" : "=m" (q[d]));
+ asm volatile("pxor %xmm4,%xmm4");
+ }
+
+ raid6_after_sse2(&sa);
+ asm volatile("sfence" : : : "memory");
+}
+
+const struct raid6_calls raid6_sse2x1 = {
+ raid6_sse21_gen_syndrome,
+ raid6_have_sse2,
+ "sse2x1",
+ 1 /* Has cache hints */
+};
+
+/*
+ * Unrolled-by-2 SSE2 implementation
+ */
+static void raid6_sse22_gen_syndrome(int disks, size_t bytes, void **ptrs)
+{
+ u8 **dptr = (u8 **)ptrs;
+ u8 *p, *q;
+ int d, z, z0;
+ raid6_sse_save_t sa;
+
+ z0 = disks - 3; /* Highest data disk */
+ p = dptr[z0+1]; /* XOR parity */
+ q = dptr[z0+2]; /* RS syndrome */
+
+ raid6_before_sse2(&sa);
+
+ asm volatile("movdqa %0,%%xmm0" : : "m" (raid6_sse_constants.x1d[0]));
+ asm volatile("pxor %xmm5,%xmm5"); /* Zero temp */
+ asm volatile("pxor %xmm7,%xmm7"); /* Zero temp */
+
+ /* We uniformly assume a single prefetch covers at least 32 bytes */
+ for ( d = 0 ; d < bytes ; d += 32 ) {
+ asm volatile("prefetchnta %0" : : "m" (dptr[z0][d]));
+ asm volatile("movdqa %0,%%xmm2" : : "m" (dptr[z0][d])); /* P[0] */
+ asm volatile("movdqa %0,%%xmm3" : : "m" (dptr[z0][d+16])); /* P[1] */
+ asm volatile("movdqa %xmm2,%xmm4"); /* Q[0] */
+ asm volatile("movdqa %xmm3,%xmm6"); /* Q[1] */
+ for ( z = z0-1 ; z >= 0 ; z-- ) {
+ asm volatile("prefetchnta %0" : : "m" (dptr[z][d]));
+ asm volatile("pcmpgtb %xmm4,%xmm5");
+ asm volatile("pcmpgtb %xmm6,%xmm7");
+ asm volatile("paddb %xmm4,%xmm4");
+ asm volatile("paddb %xmm6,%xmm6");
+ asm volatile("pand %xmm0,%xmm5");
+ asm volatile("pand %xmm0,%xmm7");
+ asm volatile("pxor %xmm5,%xmm4");
+ asm volatile("pxor %xmm7,%xmm6");
+ asm volatile("movdqa %0,%%xmm5" : : "m" (dptr[z][d]));
+ asm volatile("movdqa %0,%%xmm7" : : "m" (dptr[z][d+16]));
+ asm volatile("pxor %xmm5,%xmm2");
+ asm volatile("pxor %xmm7,%xmm3");
+ asm volatile("pxor %xmm5,%xmm4");
+ asm volatile("pxor %xmm7,%xmm6");
+ asm volatile("pxor %xmm5,%xmm5");
+ asm volatile("pxor %xmm7,%xmm7");
+ }
+ asm volatile("movntdq %%xmm2,%0" : "=m" (p[d]));
+ asm volatile("movntdq %%xmm3,%0" : "=m" (p[d+16]));
+ asm volatile("movntdq %%xmm4,%0" : "=m" (q[d]));
+ asm volatile("movntdq %%xmm6,%0" : "=m" (q[d+16]));
+ }
+
+ raid6_after_sse2(&sa);
+ asm volatile("sfence" : : : "memory");
+}
+
+const struct raid6_calls raid6_sse2x2 = {
+ raid6_sse22_gen_syndrome,
+ raid6_have_sse2,
+ "sse2x2",
+ 1 /* Has cache hints */
+};
+
+#endif
+
+#ifdef __x86_64__
+
+/*
+ * Unrolled-by-4 SSE2 implementation
+ */
+static void raid6_sse24_gen_syndrome(int disks, size_t bytes, void **ptrs)
+{
+ u8 **dptr = (u8 **)ptrs;
+ u8 *p, *q;
+ int d, z, z0;
+ raid6_sse16_save_t sa;
+
+ z0 = disks - 3; /* Highest data disk */
+ p = dptr[z0+1]; /* XOR parity */
+ q = dptr[z0+2]; /* RS syndrome */
+
+ raid6_before_sse16(&sa);
+
+ asm volatile("movdqa %0,%%xmm0" :: "m" (raid6_sse_constants.x1d[0]));
+ asm volatile("pxor %xmm2,%xmm2"); /* P[0] */
+ asm volatile("pxor %xmm3,%xmm3"); /* P[1] */
+ asm volatile("pxor %xmm4,%xmm4"); /* Q[0] */
+ asm volatile("pxor %xmm5,%xmm5"); /* Zero temp */
+ asm volatile("pxor %xmm6,%xmm6"); /* Q[1] */
+ asm volatile("pxor %xmm7,%xmm7"); /* Zero temp */
+ asm volatile("pxor %xmm10,%xmm10"); /* P[2] */
+ asm volatile("pxor %xmm11,%xmm11"); /* P[3] */
+ asm volatile("pxor %xmm12,%xmm12"); /* Q[2] */
+ asm volatile("pxor %xmm13,%xmm13"); /* Zero temp */
+ asm volatile("pxor %xmm14,%xmm14"); /* Q[3] */
+ asm volatile("pxor %xmm15,%xmm15"); /* Zero temp */
+
+ for ( d = 0 ; d < bytes ; d += 64 ) {
+ for ( z = z0 ; z >= 0 ; z-- ) {
+ /* The second prefetch seems to improve performance... */
+ asm volatile("prefetchnta %0" :: "m" (dptr[z][d]));
+ asm volatile("prefetchnta %0" :: "m" (dptr[z][d+32]));
+ asm volatile("pcmpgtb %xmm4,%xmm5");
+ asm volatile("pcmpgtb %xmm6,%xmm7");
+ asm volatile("pcmpgtb %xmm12,%xmm13");
+ asm volatile("pcmpgtb %xmm14,%xmm15");
+ asm volatile("paddb %xmm4,%xmm4");
+ asm volatile("paddb %xmm6,%xmm6");
+ asm volatile("paddb %xmm12,%xmm12");
+ asm volatile("paddb %xmm14,%xmm14");
+ asm volatile("pand %xmm0,%xmm5");
+ asm volatile("pand %xmm0,%xmm7");
+ asm volatile("pand %xmm0,%xmm13");
+ asm volatile("pand %xmm0,%xmm15");
+ asm volatile("pxor %xmm5,%xmm4");
+ asm volatile("pxor %xmm7,%xmm6");
+ asm volatile("pxor %xmm13,%xmm12");
+ asm volatile("pxor %xmm15,%xmm14");
+ asm volatile("movdqa %0,%%xmm5" :: "m" (dptr[z][d]));
+ asm volatile("movdqa %0,%%xmm7" :: "m" (dptr[z][d+16]));
+ asm volatile("movdqa %0,%%xmm13" :: "m" (dptr[z][d+32]));
+ asm volatile("movdqa %0,%%xmm15" :: "m" (dptr[z][d+48]));
+ asm volatile("pxor %xmm5,%xmm2");
+ asm volatile("pxor %xmm7,%xmm3");
+ asm volatile("pxor %xmm13,%xmm10");
+ asm volatile("pxor %xmm15,%xmm11");
+ asm volatile("pxor %xmm5,%xmm4");
+ asm volatile("pxor %xmm7,%xmm6");
+ asm volatile("pxor %xmm13,%xmm12");
+ asm volatile("pxor %xmm15,%xmm14");
+ asm volatile("pxor %xmm5,%xmm5");
+ asm volatile("pxor %xmm7,%xmm7");
+ asm volatile("pxor %xmm13,%xmm13");
+ asm volatile("pxor %xmm15,%xmm15");
+ }
+ asm volatile("movntdq %%xmm2,%0" : "=m" (p[d]));
+ asm volatile("pxor %xmm2,%xmm2");
+ asm volatile("movntdq %%xmm3,%0" : "=m" (p[d+16]));
+ asm volatile("pxor %xmm3,%xmm3");
+ asm volatile("movntdq %%xmm10,%0" : "=m" (p[d+32]));
+ asm volatile("pxor %xmm10,%xmm10");
+ asm volatile("movntdq %%xmm11,%0" : "=m" (p[d+48]));
+ asm volatile("pxor %xmm11,%xmm11");
+ asm volatile("movntdq %%xmm4,%0" : "=m" (q[d]));
+ asm volatile("pxor %xmm4,%xmm4");
+ asm volatile("movntdq %%xmm6,%0" : "=m" (q[d+16]));
+ asm volatile("pxor %xmm6,%xmm6");
+ asm volatile("movntdq %%xmm12,%0" : "=m" (q[d+32]));
+ asm volatile("pxor %xmm12,%xmm12");
+ asm volatile("movntdq %%xmm14,%0" : "=m" (q[d+48]));
+ asm volatile("pxor %xmm14,%xmm14");
+ }
+ asm volatile("sfence" : : : "memory");
+ raid6_after_sse16(&sa);
+}
+
+const struct raid6_calls raid6_sse2x4 = {
+ raid6_sse24_gen_syndrome,
+ raid6_have_sse2,
+ "sse2x4",
+ 1 /* Has cache hints */
+};
+
+#endif
diff -puN /dev/null drivers/md/raid6test/Makefile
--- /dev/null 2002-08-30 16:31:37.000000000 -0700
+++ 25-akpm/drivers/md/raid6test/Makefile 2004-01-07 22:20:04.000000000 -0800
@@ -0,0 +1,56 @@
+#
+# This is a simple Makefile to test some of the RAID-6 code
+# from userspace.
+#
+
+CC = gcc
+CFLAGS = -I.. -O2 -g -march=i686
+LD = ld
+PERL = perl
+
+.c.o:
+ $(CC) $(CFLAGS) -c -o $@ $<
+
+%.c: ../%.c
+ cp -f $< $@
+
+%.uc: ../%.uc
+ cp -f $< $@
+
+%.pl: ../%.pl
+ cp -f $< $@
+
+all: raid6.o raid6test
+
+raid6.o: raid6int1.o raid6int2.o raid6int4.o raid6int8.o raid6int16.o \
+ raid6mmx.o raid6sse1.o raid6sse2.o \
+ raid6recov.o raid6algos.o \
+ raid6tables.o
+ $(LD) -r -o $@ $^
+
+raid6test: raid6.o test.c
+ $(CC) $(CFLAGS) -o raid6test $^
+
+raid6int1.c: raid6int.uc unroller.pl
+ $(PERL) ./unroller.pl 1 < raid6int.uc > $@
+
+raid6int2.c: raid6int.uc unroller.pl
+ $(PERL) ./unroller.pl 2 < raid6int.uc > $@
+
+raid6int4.c: raid6int.uc unroller.pl
+ $(PERL) ./unroller.pl 4 < raid6int.uc > $@
+
+raid6int8.c: raid6int.uc unroller.pl
+ $(PERL) ./unroller.pl 8 < raid6int.uc > $@
+
+raid6int16.c: raid6int.uc unroller.pl
+ $(PERL) ./unroller.pl 16 < raid6int.uc > $@
+
+raid6tables.c: mktables
+ ./mktables > raid6tables.c
+
+clean:
+ rm -f *.o mktables mktables.c raid6int.uc raid6*.c raid6test
+
+spotless: clean
+ rm -f *~
diff -puN /dev/null drivers/md/raid6test/test.c
--- /dev/null 2002-08-30 16:31:37.000000000 -0700
+++ 25-akpm/drivers/md/raid6test/test.c 2004-01-07 22:20:04.000000000 -0800
@@ -0,0 +1,98 @@
+/* -*- 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,
+ * Bostom MA 02111-1307, USA; either version 2 of the License, or
+ * (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * raid6test.c
+ *
+ * Test RAID-6 recovery with various algorithms
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include "raid6.h"
+
+#define NDISKS 16 /* Including P and Q */
+
+const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(256)));
+struct raid6_calls raid6_call;
+
+char *dataptrs[NDISKS];
+char data[NDISKS][PAGE_SIZE];
+char recovi[PAGE_SIZE], recovj[PAGE_SIZE];
+
+void makedata(void)
+{
+ int i, j;
+
+ for ( i = 0 ; i < NDISKS ; i++ ) {
+ for ( j = 0 ; j < PAGE_SIZE ; j++ ) {
+ data[i][j] = rand();
+ }
+ dataptrs[i] = data[i];
+ }
+}
+
+int main(int argc, char *argv[])
+{
+ const struct raid6_calls * const * algo;
+ int i, j;
+ int erra, errb;
+
+ makedata();
+
+ for ( algo = raid6_algos ; *algo ; algo++ ) {
+ if ( !(*algo)->valid || (*algo)->valid() ) {
+ raid6_call = **algo;
+
+ /* Nuke syndromes */
+ memset(data[NDISKS-2], 0xee, 2*PAGE_SIZE);
+
+ /* Generate assumed good syndrome */
+ raid6_call.gen_syndrome(NDISKS, PAGE_SIZE, (void **)&dataptrs);
+
+ for ( i = 0 ; i < NDISKS-1 ; i++ ) {
+ for ( j = i+1 ; j < NDISKS ; j++ ) {
+ memset(recovi, 0xf0, PAGE_SIZE);
+ memset(recovj, 0xba, PAGE_SIZE);
+
+ dataptrs[i] = recovi;
+ dataptrs[j] = recovj;
+
+ raid6_dual_recov(NDISKS, PAGE_SIZE, i, j, (void **)&dataptrs);
+
+ erra = memcmp(data[i], recovi, PAGE_SIZE);
+ errb = memcmp(data[j], recovj, PAGE_SIZE);
+
+ printf("algo=%-8s faila=%3d(%c) failb=%3d(%c) %s\n",
+ raid6_call.name,
+ i, (i==NDISKS-2)?'P':'D',
+ j, (j==NDISKS-1)?'Q':(j==NDISKS-2)?'P':'D',
+ (!erra && !errb) ? "OK" :
+ !erra ? "ERRB" :
+ !errb ? "ERRA" :
+ "ERRAB");
+
+ dataptrs[i] = data[i];
+ dataptrs[j] = data[j];
+ }
+ }
+ }
+ printf("\n");
+ }
+
+ printf("\n");
+ /* Pick the best algorithm test */
+ raid6_select_algo();
+
+ return 0;
+}
diff -puN /dev/null drivers/md/raid6x86.h
--- /dev/null 2002-08-30 16:31:37.000000000 -0700
+++ 25-akpm/drivers/md/raid6x86.h 2004-01-07 22:20:04.000000000 -0800
@@ -0,0 +1,242 @@
+#ident "$Id: raid6-20040107.patch,v 1.1 2004/01/08 06:20:43 akpm Exp $"
+/* ----------------------------------------------------------------------- *
+ *
+ * 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,
+ * Bostom MA 02111-1307, USA; either version 2 of the License, or
+ * (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * raid6x86.h
+ *
+ * Definitions common to x86 and x86-64 RAID-6 code only
+ */
+
+#ifndef LINUX_RAID_RAID6X86_H
+#define LINUX_RAID_RAID6X86_H
+
+#if defined(__i386__) || defined(__x86_64__)
+
+typedef struct {
+ unsigned int fsave[27];
+ unsigned int cr0;
+} raid6_mmx_save_t;
+
+/* N.B.: For SSE we only save %xmm0-%xmm7 even for x86-64, since
+ the code doesn't know about the additional x86-64 registers */
+/* The +3 is so we can make sure the area is aligned properly */
+typedef struct {
+ unsigned int sarea[8*4+3];
+ unsigned int cr0;
+} raid6_sse_save_t __attribute__((aligned(16)));
+
+#ifdef __x86_64__
+
+/* This is for x86-64-specific code which uses all 16 XMM registers */
+typedef struct {
+ unsigned int sarea[16*4+3];
+ unsigned int cr0;
+} raid6_sse16_save_t __attribute__((aligned(16)));
+
+#endif
+
+#ifdef __KERNEL__ /* Real code */
+
+ static inline u32 raid6_get_fpu(void)
+{
+ u32 cr0;
+
+ preempt_disable();
+ asm volatile("movl %%cr0,%0 ; clts" : "=r" (cr0));
+ return cr0;
+}
+
+static inline void raid6_put_fpu(u32 cr0)
+{
+ asm volatile("movl %0,%%cr0" : : "r" (cr0));
+ preempt_enable();
+}
+
+#else /* Dummy code for user space testing */
+
+static inline u32 raid6_get_fpu(void)
+{
+ return 0xf00ba6;
+}
+
+static inline void raid6_put_fpu(u32 cr0)
+{
+ (void)cr0;
+}
+
+#endif
+
+static inline void raid6_before_mmx(raid6_mmx_save_t *s)
+{
+ s->cr0 = raid6_get_fpu();
+ asm volatile("fsave %0 ; fwait" : "=m" (s->fsave[0]));
+}
+
+static inline void raid6_after_mmx(raid6_mmx_save_t *s)
+{
+ asm volatile("frstor %0" : : "m" (s->fsave[0]));
+ raid6_put_fpu(s->cr0);
+}
+
+static inline void raid6_before_sse(raid6_sse_save_t *s)
+{
+#ifdef __x86_64__
+ unsigned int *rsa = s->sarea;
+#else
+ /* On i386 the save area may not be aligned */
+ unsigned int *rsa =
+ (unsigned int *)((((unsigned long)&s->sarea)+15) & ~15);
+#endif
+ s->cr0 = raid6_get_fpu();
+
+ asm volatile("movaps %%xmm0,%0" : "=m" (rsa[0]));
+ asm volatile("movaps %%xmm1,%0" : "=m" (rsa[4]));
+ asm volatile("movaps %%xmm2,%0" : "=m" (rsa[8]));
+ asm volatile("movaps %%xmm3,%0" : "=m" (rsa[12]));
+ asm volatile("movaps %%xmm4,%0" : "=m" (rsa[16]));
+ asm volatile("movaps %%xmm5,%0" : "=m" (rsa[20]));
+ asm volatile("movaps %%xmm6,%0" : "=m" (rsa[24]));
+ asm volatile("movaps %%xmm7,%0" : "=m" (rsa[28]));
+}
+
+static inline void raid6_after_sse(raid6_sse_save_t *s)
+{
+#ifdef __x86_64__
+ unsigned int *rsa = s->sarea;
+#else
+ /* On i386 the save area may not be aligned */
+ unsigned int *rsa =
+ (unsigned int *)((((unsigned long)&s->sarea)+15) & ~15);
+#endif
+ asm volatile("movaps %0,%%xmm0" : : "m" (rsa[0]));
+ asm volatile("movaps %0,%%xmm1" : : "m" (rsa[4]));
+ asm volatile("movaps %0,%%xmm2" : : "m" (rsa[8]));
+ asm volatile("movaps %0,%%xmm3" : : "m" (rsa[12]));
+ asm volatile("movaps %0,%%xmm4" : : "m" (rsa[16]));
+ asm volatile("movaps %0,%%xmm5" : : "m" (rsa[20]));
+ asm volatile("movaps %0,%%xmm6" : : "m" (rsa[24]));
+ asm volatile("movaps %0,%%xmm7" : : "m" (rsa[28]));
+
+ raid6_put_fpu(s->cr0);
+}
+
+static inline void raid6_before_sse2(raid6_sse_save_t *s)
+{
+#ifdef __x86_64__
+ unsigned int *rsa = &s->sarea;
+#else
+ /* On i386 the save area may not be aligned */
+ unsigned int *rsa =
+ (unsigned int *)((((unsigned long)&s->sarea)+15) & ~15);
+#endif
+ s->cr0 = raid6_get_fpu();
+
+ asm volatile("movdqa %%xmm0,%0" : "=m" (rsa[0]));
+ asm volatile("movdqa %%xmm1,%0" : "=m" (rsa[4]));
+ asm volatile("movdqa %%xmm2,%0" : "=m" (rsa[8]));
+ asm volatile("movdqa %%xmm3,%0" : "=m" (rsa[12]));
+ asm volatile("movdqa %%xmm4,%0" : "=m" (rsa[16]));
+ asm volatile("movdqa %%xmm5,%0" : "=m" (rsa[20]));
+ asm volatile("movdqa %%xmm6,%0" : "=m" (rsa[24]));
+ asm volatile("movdqa %%xmm7,%0" : "=m" (rsa[28]));
+}
+
+static inline void raid6_after_sse2(raid6_sse_save_t *s)
+{
+#ifdef __x86_64__
+ unsigned int *rsa = s->sarea;
+#else
+ /* On i386 the save area may not be aligned */
+ unsigned int *rsa =
+ (unsigned int *)((((unsigned long)&s->sarea)+15) & ~15);
+#endif
+ asm volatile("movdqa %0,%%xmm0" : : "m" (rsa[0]));
+ asm volatile("movdqa %0,%%xmm1" : : "m" (rsa[4]));
+ asm volatile("movdqa %0,%%xmm2" : : "m" (rsa[8]));
+ asm volatile("movdqa %0,%%xmm3" : : "m" (rsa[12]));
+ asm volatile("movdqa %0,%%xmm4" : : "m" (rsa[16]));
+ asm volatile("movdqa %0,%%xmm5" : : "m" (rsa[20]));
+ asm volatile("movdqa %0,%%xmm6" : : "m" (rsa[24]));
+ asm volatile("movdqa %0,%%xmm7" : : "m" (rsa[28]));
+
+ raid6_put_fpu(s->cr0);
+}
+
+#ifdef __x86_64__
+
+static inline raid6_before_sse16(raid6_sse16_save_t *s)
+{
+ unsigned int *rsa = s->sarea;
+
+ s->cr0 = raid6_get_fpu();
+
+ asm volatile("movdqa %%xmm0,%0" : "=m" (rsa[0]));
+ asm volatile("movdqa %%xmm1,%0" : "=m" (rsa[4]));
+ asm volatile("movdqa %%xmm2,%0" : "=m" (rsa[8]));
+ asm volatile("movdqa %%xmm3,%0" : "=m" (rsa[12]));
+ asm volatile("movdqa %%xmm4,%0" : "=m" (rsa[16]));
+ asm volatile("movdqa %%xmm5,%0" : "=m" (rsa[20]));
+ asm volatile("movdqa %%xmm6,%0" : "=m" (rsa[24]));
+ asm volatile("movdqa %%xmm7,%0" : "=m" (rsa[28]));
+ asm volatile("movdqa %%xmm8,%0" : "=m" (rsa[32]));
+ asm volatile("movdqa %%xmm9,%0" : "=m" (rsa[36]));
+ asm volatile("movdqa %%xmm10,%0" : "=m" (rsa[40]));
+ asm volatile("movdqa %%xmm11,%0" : "=m" (rsa[44]));
+ asm volatile("movdqa %%xmm12,%0" : "=m" (rsa[48]));
+ asm volatile("movdqa %%xmm13,%0" : "=m" (rsa[52]));
+ asm volatile("movdqa %%xmm14,%0" : "=m" (rsa[56]));
+ asm volatile("movdqa %%xmm15,%0" : "=m" (rsa[60]));
+}
+
+static inline raid6_after_sse16(raid6_sse16_save_t *s)
+{
+ unsigned int *rsa = s->sarea;
+
+ asm volatile("movdqa %0,%%xmm0" : : "m" (rsa[0]));
+ asm volatile("movdqa %0,%%xmm1" : : "m" (rsa[4]));
+ asm volatile("movdqa %0,%%xmm2" : : "m" (rsa[8]));
+ asm volatile("movdqa %0,%%xmm3" : : "m" (rsa[12]));
+ asm volatile("movdqa %0,%%xmm4" : : "m" (rsa[16]));
+ asm volatile("movdqa %0,%%xmm5" : : "m" (rsa[20]));
+ asm volatile("movdqa %0,%%xmm6" : : "m" (rsa[24]));
+ asm volatile("movdqa %0,%%xmm7" : : "m" (rsa[28]));
+ asm volatile("movdqa %0,%%xmm8" : : "m" (rsa[32]));
+ asm volatile("movdqa %0,%%xmm9" : : "m" (rsa[36]));
+ asm volatile("movdqa %0,%%xmm10" : : "m" (rsa[40]));
+ asm volatile("movdqa %0,%%xmm11" : : "m" (rsa[44]));
+ asm volatile("movdqa %0,%%xmm12" : : "m" (rsa[48]));
+ asm volatile("movdqa %0,%%xmm13" : : "m" (rsa[52]));
+ asm volatile("movdqa %0,%%xmm14" : : "m" (rsa[56]));
+ asm volatile("movdqa %0,%%xmm15" : : "m" (rsa[60]));
+
+ raid6_put_fpu(s->cr0);
+}
+
+#endif /* __x86_64__ */
+
+/* User space test hack */
+#ifndef __KERNEL__
+static inline int cpuid_features(void)
+{
+ u32 eax = 1;
+ u32 ebx, ecx, edx;
+
+ asm volatile("cpuid" :
+ "+a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx));
+
+ return edx;
+}
+#endif /* ndef __KERNEL__ */
+
+#endif
+#endif
diff -puN /dev/null drivers/md/unroll.pl
--- /dev/null 2002-08-30 16:31:37.000000000 -0700
+++ 25-akpm/drivers/md/unroll.pl 2004-01-07 22:20:04.000000000 -0800
@@ -0,0 +1,24 @@
+#!/usr/bin/perl
+#
+# Take a piece of C code and for each line which contains the sequence $$
+# repeat n times with $ replaced by 0...n-1; the sequence $# is replaced
+# by the unrolling factor, and $* with a single $
+#
+
+($n) = @ARGV;
+$n += 0;
+
+while ( defined($line = <STDIN>) ) {
+ if ( $line =~ /\$\$/ ) {
+ $rep = $n;
+ } else {
+ $rep = 1;
+ }
+ for ( $i = 0 ; $i < $rep ; $i++ ) {
+ $tmp = $line;
+ $tmp =~ s/\$\$/$i/g;
+ $tmp =~ s/\$\#/$n/g;
+ $tmp =~ s/\$\*/\$/g;
+ print $tmp;
+ }
+}
diff -puN include/linux/raid/md_k.h~raid6-20040107 include/linux/raid/md_k.h
--- 25/include/linux/raid/md_k.h~raid6-20040107 2004-01-07 22:20:04.000000000 -0800
+++ 25-akpm/include/linux/raid/md_k.h 2004-01-07 22:20:04.000000000 -0800
@@ -23,7 +23,8 @@
#define TRANSLUCENT 5UL
#define HSM 6UL
#define MULTIPATH 7UL
-#define MAX_PERSONALITY 8UL
+#define RAID6 8UL
+#define MAX_PERSONALITY 9UL
#define LEVEL_MULTIPATH (-4)
#define LEVEL_LINEAR (-1)
@@ -41,6 +42,7 @@ static inline int pers_to_level (int per
case RAID0: return 0;
case RAID1: return 1;
case RAID5: return 5;
+ case RAID6: return 6;
}
BUG();
return MD_RESERVED;
@@ -57,6 +59,7 @@ static inline int level_to_pers (int lev
case 1: return RAID1;
case 4:
case 5: return RAID5;
+ case 6: return RAID6;
}
return MD_RESERVED;
}
_