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authorQu Wenruo <quwenruo@cn.fujitsu.com>2016-09-30 13:04:54 +0800
committerDavid Sterba <dsterba@suse.com>2016-10-24 15:03:20 +0200
commitfd48a96b9abab6845c0b148e91f520e74d385d85 (patch)
treeac12e2fcfe6ec441871434b0441902360cc3e239 /raid56.c
parent112514568fbe266943d7dd5ed3d2a6a8ab01a1de (diff)
btrfs-progs: rename raid6.c to raid56.c
This allows us to put raid5 codes into that file other than creating a new raid5.c. Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'raid56.c')
-rw-r--r--raid56.c109
1 files changed, 109 insertions, 0 deletions
diff --git a/raid56.c b/raid56.c
new file mode 100644
index 00000000..833df5f3
--- /dev/null
+++ b/raid56.c
@@ -0,0 +1,109 @@
+/* -*- linux-c -*- ------------------------------------------------------- *
+ *
+ * Copyright 2002-2004 H. Peter Anvin - All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, Inc., 53 Temple Place Ste 330,
+ * Boston MA 02111-1307, USA; either version 2 of the License, or
+ * (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * Added helpers for unaligned native int access
+ */
+
+/*
+ * raid6int1.c
+ *
+ * 1-way unrolled portable integer math RAID-6 instruction set
+ *
+ * This file was postprocessed using unroll.pl and then ported to userspace
+ */
+#include <stdint.h>
+#include <unistd.h>
+#include "kerncompat.h"
+#include "ctree.h"
+#include "disk-io.h"
+
+/*
+ * This is the C data type to use
+ */
+
+/* Change this from BITS_PER_LONG if there is something better... */
+#if BITS_PER_LONG == 64
+# define NBYTES(x) ((x) * 0x0101010101010101UL)
+# define NSIZE 8
+# define NSHIFT 3
+typedef uint64_t unative_t;
+#define put_unaligned_native(val,p) put_unaligned_64((val),(p))
+#define get_unaligned_native(p) get_unaligned_64((p))
+#else
+# define NBYTES(x) ((x) * 0x01010101U)
+# define NSIZE 4
+# define NSHIFT 2
+typedef uint32_t unative_t;
+#define put_unaligned_native(val,p) put_unaligned_32((val),(p))
+#define get_unaligned_native(p) get_unaligned_32((p))
+#endif
+
+/*
+ * These sub-operations are separate inlines since they can sometimes be
+ * specially optimized using architecture-specific hacks.
+ */
+
+/*
+ * The SHLBYTE() operation shifts each byte left by 1, *not*
+ * rolling over into the next byte
+ */
+static inline __attribute_const__ unative_t SHLBYTE(unative_t v)
+{
+ unative_t vv;
+
+ vv = (v << 1) & NBYTES(0xfe);
+ return vv;
+}
+
+/*
+ * The MASK() operation returns 0xFF in any byte for which the high
+ * bit is 1, 0x00 for any byte for which the high bit is 0.
+ */
+static inline __attribute_const__ unative_t MASK(unative_t v)
+{
+ unative_t vv;
+
+ vv = v & NBYTES(0x80);
+ vv = (vv << 1) - (vv >> 7); /* Overflow on the top bit is OK */
+ return vv;
+}
+
+
+void raid6_gen_syndrome(int disks, size_t bytes, void **ptrs)
+{
+ uint8_t **dptr = (uint8_t **)ptrs;
+ uint8_t *p, *q;
+ int d, z, z0;
+
+ unative_t wd0, wq0, wp0, w10, w20;
+
+ z0 = disks - 3; /* Highest data disk */
+ p = dptr[z0+1]; /* XOR parity */
+ q = dptr[z0+2]; /* RS syndrome */
+
+ for ( d = 0 ; d < bytes ; d += NSIZE*1 ) {
+ wq0 = wp0 = get_unaligned_native(&dptr[z0][d+0*NSIZE]);
+ for ( z = z0-1 ; z >= 0 ; z-- ) {
+ wd0 = get_unaligned_native(&dptr[z][d+0*NSIZE]);
+ wp0 ^= wd0;
+ w20 = MASK(wq0);
+ w10 = SHLBYTE(wq0);
+ w20 &= NBYTES(0x1d);
+ w10 ^= w20;
+ wq0 = w10 ^ wd0;
+ }
+ put_unaligned_native(wp0, &p[d+NSIZE*0]);
+ put_unaligned_native(wq0, &q[d+NSIZE*0]);
+ }
+}
+