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-rw-r--r--src/common/crc32c_ppc.c148
1 files changed, 148 insertions, 0 deletions
diff --git a/src/common/crc32c_ppc.c b/src/common/crc32c_ppc.c
new file mode 100644
index 000000000..52fd1c4ee
--- /dev/null
+++ b/src/common/crc32c_ppc.c
@@ -0,0 +1,148 @@
+/* Copyright (C) 2017 International Business Machines Corp.
+ * 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; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#define CRC_TABLE
+#define FAST_ZERO_TABLE
+
+#include "acconfig.h"
+#include "include/int_types.h"
+#include "crc32c_ppc_constants.h"
+#include "reverse.h"
+
+#include <stdlib.h>
+#include <strings.h>
+
+#define VMX_ALIGN 16
+#define VMX_ALIGN_MASK (VMX_ALIGN-1)
+
+#ifdef HAVE_PPC64LE
+#ifdef REFLECT
+static unsigned int crc32_align(unsigned int crc, unsigned char const *p,
+ unsigned long len)
+{
+ while (len--)
+ crc = crc_table[(crc ^ *p++) & 0xff] ^ (crc >> 8);
+ return crc;
+}
+#else
+static unsigned int crc32_align(unsigned int crc, unsigned char const *p,
+ unsigned long len)
+{
+ while (len--)
+ crc = crc_table[((crc >> 24) ^ *p++) & 0xff] ^ (crc << 8);
+ return crc;
+}
+#endif
+
+static inline unsigned long polynomial_multiply(unsigned int a, unsigned int b) {
+ vector unsigned int va = {a, 0, 0, 0};
+ vector unsigned int vb = {b, 0, 0, 0};
+ vector unsigned long vt;
+
+ __asm__("vpmsumw %0,%1,%2" : "=v"(vt) : "v"(va), "v"(vb));
+
+ return vt[0];
+}
+
+unsigned int barrett_reduction(unsigned long val);
+
+static inline unsigned int gf_multiply(unsigned int a, unsigned int b) {
+ return barrett_reduction(polynomial_multiply(a, b));
+}
+
+unsigned int append_zeros(unsigned int crc, unsigned long length) {
+ unsigned long i = 0;
+
+ while (length) {
+ if (length & 1) {
+ crc = gf_multiply(crc, crc_zero[i]);
+ }
+ i++;
+ length /= 2;
+ }
+
+ return crc;
+}
+
+
+unsigned int __crc32_vpmsum(unsigned int crc, unsigned char const *p,
+ unsigned long len);
+
+static uint32_t crc32_vpmsum(uint32_t crc, unsigned char const *data,
+ unsigned len)
+{
+ unsigned int prealign;
+ unsigned int tail;
+
+#ifdef CRC_XOR
+ crc ^= 0xffffffff;
+#endif
+
+ if (len < VMX_ALIGN + VMX_ALIGN_MASK) {
+ crc = crc32_align(crc, data, (unsigned long)len);
+ goto out;
+ }
+
+ if ((unsigned long)data & VMX_ALIGN_MASK) {
+ prealign = VMX_ALIGN - ((unsigned long)data & VMX_ALIGN_MASK);
+ crc = crc32_align(crc, data, prealign);
+ len -= prealign;
+ data += prealign;
+ }
+
+ crc = __crc32_vpmsum(crc, data, (unsigned long)len & ~VMX_ALIGN_MASK);
+
+ tail = len & VMX_ALIGN_MASK;
+ if (tail) {
+ data += len & ~VMX_ALIGN_MASK;
+ crc = crc32_align(crc, data, tail);
+ }
+
+out:
+#ifdef CRC_XOR
+ crc ^= 0xffffffff;
+#endif
+
+ return crc;
+}
+
+/* This wrapper function works around the fact that crc32_vpmsum
+ * does not gracefully handle the case where the data pointer is NULL.
+ */
+uint32_t ceph_crc32c_ppc(uint32_t crc, unsigned char const *data, unsigned len)
+{
+ if (!data) {
+ /* Handle the NULL buffer case. */
+#ifdef REFLECT
+ crc = reverse_bits(crc);
+#endif
+
+ crc = append_zeros(crc, len);
+
+#ifdef REFLECT
+ crc = reverse_bits(crc);
+#endif
+ } else {
+ /* Handle the valid buffer case. */
+ crc = crc32_vpmsum(crc, data, (unsigned long)len);
+ }
+ return crc;
+}
+
+#else /* HAVE_PPC64LE */
+
+/* This symbol has to exist on non-ppc architectures (and on legacy
+ * ppc systems using power7 or below) in order to compile properly
+ * there, even though it won't be called.
+ */
+uint32_t ceph_crc32c_ppc(uint32_t crc, unsigned char const *data, unsigned len)
+{
+ return 0;
+}
+
+#endif /* HAVE_PPC64LE */