Revert "net, lib: kill arch_fast_hash library bits"

This reverts commit 0cb6c969ed.

arch/alpha/include/asm/Kbuild

@@ -3,6 +3,7 @@
 generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += exec.h
+generic-y += hash.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += mm-arch-hooks.h

arch/arc/include/asm/Kbuild

@@ -11,6 +11,7 @@ generic-y += fb.h
 generic-y += fcntl.h
 generic-y += ftrace.h
 generic-y += hardirq.h
+generic-y += hash.h
 generic-y += hw_irq.h
 generic-y += ioctl.h
 generic-y += ioctls.h

arch/arm/include/asm/Kbuild

@@ -6,6 +6,7 @@ generic-y += current.h
 generic-y += emergency-restart.h
 generic-y += errno.h
 generic-y += exec.h
+generic-y += hash.h
 generic-y += ioctl.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h

arch/arm64/include/asm/Kbuild

@@ -14,6 +14,7 @@ generic-y += early_ioremap.h
 generic-y += emergency-restart.h
 generic-y += errno.h
 generic-y += ftrace.h
+generic-y += hash.h
 generic-y += hw_irq.h
 generic-y += ioctl.h
 generic-y += ioctls.h

arch/avr32/include/asm/Kbuild

@@ -7,6 +7,7 @@ generic-y += div64.h
 generic-y += emergency-restart.h
 generic-y += exec.h
 generic-y += futex.h
+generic-y += hash.h
 generic-y += irq_regs.h
 generic-y += irq_work.h
 generic-y += local.h

arch/blackfin/include/asm/Kbuild

@@ -10,6 +10,7 @@ generic-y += emergency-restart.h
 generic-y += errno.h
 generic-y += fb.h
 generic-y += futex.h
+generic-y += hash.h
 generic-y += hw_irq.h
 generic-y += ioctl.h
 generic-y += ipcbuf.h

arch/c6x/include/asm/Kbuild

@@ -15,6 +15,7 @@ generic-y += exec.h
 generic-y += fb.h
 generic-y += fcntl.h
 generic-y += futex.h
+generic-y += hash.h
 generic-y += hw_irq.h
 generic-y += io.h
 generic-y += ioctl.h

arch/frv/include/asm/Kbuild

@@ -2,6 +2,7 @@
 generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += exec.h
+generic-y += hash.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += mm-arch-hooks.h

arch/hexagon/include/asm/Kbuild

@@ -16,6 +16,7 @@ generic-y += fb.h
 generic-y += fcntl.h
 generic-y += ftrace.h
 generic-y += hardirq.h
+generic-y += hash.h
 generic-y += hw_irq.h
 generic-y += ioctl.h
 generic-y += ioctls.h

arch/ia64/include/asm/Kbuild

@@ -1,6 +1,7 @@
 
 generic-y += clkdev.h
 generic-y += exec.h
+generic-y += hash.h
 generic-y += irq_work.h
 generic-y += kvm_para.h
 generic-y += mcs_spinlock.h

arch/m32r/include/asm/Kbuild

@@ -2,6 +2,7 @@
 generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += exec.h
+generic-y += hash.h
 generic-y += irq_work.h
 generic-y += kvm_para.h
 generic-y += mcs_spinlock.h

arch/metag/include/asm/Kbuild

@@ -13,6 +13,7 @@ generic-y += fb.h
 generic-y += fcntl.h
 generic-y += futex.h
 generic-y += hardirq.h
+generic-y += hash.h
 generic-y += hw_irq.h
 generic-y += ioctl.h
 generic-y += ioctls.h

arch/microblaze/include/asm/Kbuild

@@ -4,6 +4,7 @@ generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += device.h
 generic-y += exec.h
+generic-y += hash.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += mm-arch-hooks.h

arch/mips/include/asm/Kbuild

@@ -4,6 +4,7 @@ generic-y += cputime.h
 generic-y += current.h
 generic-y += dma-contiguous.h
 generic-y += emergency-restart.h
+generic-y += hash.h
 generic-y += irq_work.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h

arch/mn10300/include/asm/Kbuild

@@ -3,6 +3,7 @@ generic-y += barrier.h
 generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += exec.h
+generic-y += hash.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += mm-arch-hooks.h

arch/openrisc/include/asm/Kbuild

@@ -25,6 +25,7 @@ generic-y += fcntl.h
 generic-y += ftrace.h
 generic-y += futex.h
 generic-y += hardirq.h
+generic-y += hash.h
 generic-y += hw_irq.h
 generic-y += ioctl.h
 generic-y += ioctls.h

arch/parisc/include/asm/Kbuild

@@ -7,6 +7,7 @@ generic-y += device.h
 generic-y += div64.h
 generic-y += emergency-restart.h
 generic-y += exec.h
+generic-y += hash.h
 generic-y += hw_irq.h
 generic-y += irq_regs.h
 generic-y += irq_work.h

arch/s390/include/asm/Kbuild

@@ -1,6 +1,7 @@
 
 
 generic-y += clkdev.h
+generic-y += hash.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += mm-arch-hooks.h

arch/score/include/asm/Kbuild

@@ -5,6 +5,7 @@ header-y +=
 generic-y += barrier.h
 generic-y += clkdev.h
 generic-y += cputime.h
+generic-y += hash.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += mm-arch-hooks.h

arch/sh/include/asm/Kbuild

@@ -8,6 +8,7 @@ generic-y += emergency-restart.h
 generic-y += errno.h
 generic-y += exec.h
 generic-y += fcntl.h
+generic-y += hash.h
 generic-y += ioctl.h
 generic-y += ipcbuf.h
 generic-y += irq_regs.h

arch/sparc/include/asm/Kbuild

@@ -6,6 +6,7 @@ generic-y += cputime.h
 generic-y += div64.h
 generic-y += emergency-restart.h
 generic-y += exec.h
+generic-y += hash.h
 generic-y += irq_regs.h
 generic-y += irq_work.h
 generic-y += linkage.h

arch/tile/include/asm/Kbuild

@@ -11,6 +11,7 @@ generic-y += errno.h
 generic-y += exec.h
 generic-y += fb.h
 generic-y += fcntl.h
+generic-y += hash.h
 generic-y += hw_irq.h
 generic-y += ioctl.h
 generic-y += ioctls.h

arch/um/include/asm/Kbuild

@@ -10,6 +10,7 @@ generic-y += exec.h
 generic-y += ftrace.h
 generic-y += futex.h
 generic-y += hardirq.h
+generic-y += hash.h
 generic-y += hw_irq.h
 generic-y += io.h
 generic-y += irq_regs.h

arch/unicore32/include/asm/Kbuild

@@ -16,6 +16,7 @@ generic-y += fcntl.h
 generic-y += ftrace.h
 generic-y += futex.h
 generic-y += hardirq.h
+generic-y += hash.h
 generic-y += hw_irq.h
 generic-y += ioctl.h
 generic-y += ioctls.h

arch/x86/include/asm/hash.h

@@ -0,0 +1,7 @@
+#ifndef _ASM_X86_HASH_H
+#define _ASM_X86_HASH_H
+
+struct fast_hash_ops;
+extern void setup_arch_fast_hash(struct fast_hash_ops *ops);
+
+#endif /* _ASM_X86_HASH_H */

arch/x86/lib/Makefile

@@ -22,7 +22,7 @@ lib-y += memcpy_$(BITS).o
 lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o
 lib-$(CONFIG_INSTRUCTION_DECODER) += insn.o inat.o
 
-obj-y += msr.o msr-reg.o msr-reg-export.o
+obj-y += msr.o msr-reg.o msr-reg-export.o hash.o
 
 ifeq ($(CONFIG_X86_32),y)
         obj-y += atomic64_32.o

arch/x86/lib/hash.c

@@ -0,0 +1,92 @@
+/*
+ * Some portions derived from code covered by the following notice:
+ *
+ * Copyright (c) 2010-2013 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in
+ *     the documentation and/or other materials provided with the
+ *     distribution.
+ *   * Neither the name of Intel Corporation nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/hash.h>
+#include <linux/init.h>
+
+#include <asm/processor.h>
+#include <asm/cpufeature.h>
+#include <asm/hash.h>
+
+static inline u32 crc32_u32(u32 crc, u32 val)
+{
+#ifdef CONFIG_AS_CRC32
+	asm ("crc32l %1,%0\n" : "+r" (crc) : "rm" (val));
+#else
+	asm (".byte 0xf2, 0x0f, 0x38, 0xf1, 0xc1" : "+a" (crc) : "c" (val));
+#endif
+	return crc;
+}
+
+static u32 intel_crc4_2_hash(const void *data, u32 len, u32 seed)
+{
+	const u32 *p32 = (const u32 *) data;
+	u32 i, tmp = 0;
+
+	for (i = 0; i < len / 4; i++)
+		seed = crc32_u32(seed, *p32++);
+
+	switch (len & 3) {
+	case 3:
+		tmp |= *((const u8 *) p32 + 2) << 16;
+		/* fallthrough */
+	case 2:
+		tmp |= *((const u8 *) p32 + 1) << 8;
+		/* fallthrough */
+	case 1:
+		tmp |= *((const u8 *) p32);
+		seed = crc32_u32(seed, tmp);
+		break;
+	}
+
+	return seed;
+}
+
+static u32 intel_crc4_2_hash2(const u32 *data, u32 len, u32 seed)
+{
+	const u32 *p32 = (const u32 *) data;
+	u32 i;
+
+	for (i = 0; i < len; i++)
+		seed = crc32_u32(seed, *p32++);
+
+	return seed;
+}
+
+void __init setup_arch_fast_hash(struct fast_hash_ops *ops)
+{
+	if (cpu_has_xmm4_2) {
+		ops->hash  = intel_crc4_2_hash;
+		ops->hash2 = intel_crc4_2_hash2;
+	}
+}

arch/xtensa/include/asm/Kbuild

@@ -8,6 +8,7 @@ generic-y += errno.h
 generic-y += exec.h
 generic-y += fcntl.h
 generic-y += hardirq.h
+generic-y += hash.h
 generic-y += ioctl.h
 generic-y += irq_regs.h
 generic-y += irq_work.h

include/asm-generic/hash.h

@@ -0,0 +1,9 @@
+#ifndef __ASM_GENERIC_HASH_H
+#define __ASM_GENERIC_HASH_H
+
+struct fast_hash_ops;
+static inline void setup_arch_fast_hash(struct fast_hash_ops *ops)
+{
+}
+
+#endif /* __ASM_GENERIC_HASH_H */

include/linux/hash.h

@@ -15,6 +15,7 @@
  */
 
 #include <asm/types.h>
+#include <asm/hash.h>
 #include <linux/compiler.h>
 
 /* 2^31 + 2^29 - 2^25 + 2^22 - 2^19 - 2^16 + 1 */
@@ -83,4 +84,38 @@ static inline u32 hash32_ptr(const void *ptr)
 	return (u32)val;
 }
 
+struct fast_hash_ops {
+	u32 (*hash)(const void *data, u32 len, u32 seed);
+	u32 (*hash2)(const u32 *data, u32 len, u32 seed);
+};
+
+/**
+ *	arch_fast_hash - Caclulates a hash over a given buffer that can have
+ *			 arbitrary size. This function will eventually use an
+ *			 architecture-optimized hashing implementation if
+ *			 available, and trades off distribution for speed.
+ *
+ *	@data: buffer to hash
+ *	@len: length of buffer in bytes
+ *	@seed: start seed
+ *
+ *	Returns 32bit hash.
+ */
+extern u32 arch_fast_hash(const void *data, u32 len, u32 seed);
+
+/**
+ *	arch_fast_hash2 - Caclulates a hash over a given buffer that has a
+ *			  size that is of a multiple of 32bit words. This
+ *			  function will eventually use an architecture-
+ *			  optimized hashing implementation if available,
+ *			  and trades off distribution for speed.
+ *
+ *	@data: buffer to hash (must be 32bit padded)
+ *	@len: number of 32bit words
+ *	@seed: start seed
+ *
+ *	Returns 32bit hash.
+ */
+extern u32 arch_fast_hash2(const u32 *data, u32 len, u32 seed);
+
 #endif /* _LINUX_HASH_H */

lib/Makefile

@@ -27,7 +27,7 @@ obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
 	 gcd.o lcm.o list_sort.o uuid.o flex_array.o iov_iter.o clz_ctz.o \
 	 bsearch.o find_bit.o llist.o memweight.o kfifo.o \
 	 percpu-refcount.o percpu_ida.o rhashtable.o reciprocal_div.o \
-	 once.o
+	 once.o hash.o
 obj-y += string_helpers.o
 obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o
 obj-y += hexdump.o

lib/hash.c

@@ -0,0 +1,39 @@
+/* General purpose hashing library
+ *
+ * That's a start of a kernel hashing library, which can be extended
+ * with further algorithms in future. arch_fast_hash{2,}() will
+ * eventually resolve to an architecture optimized implementation.
+ *
+ * Copyright 2013 Francesco Fusco <ffusco@redhat.com>
+ * Copyright 2013 Daniel Borkmann <dborkman@redhat.com>
+ * Copyright 2013 Thomas Graf <tgraf@redhat.com>
+ * Licensed under the GNU General Public License, version 2.0 (GPLv2)
+ */
+
+#include <linux/jhash.h>
+#include <linux/hash.h>
+#include <linux/cache.h>
+
+static struct fast_hash_ops arch_hash_ops __read_mostly = {
+	.hash  = jhash,
+	.hash2 = jhash2,
+};
+
+u32 arch_fast_hash(const void *data, u32 len, u32 seed)
+{
+	return arch_hash_ops.hash(data, len, seed);
+}
+EXPORT_SYMBOL_GPL(arch_fast_hash);
+
+u32 arch_fast_hash2(const u32 *data, u32 len, u32 seed)
+{
+	return arch_hash_ops.hash2(data, len, seed);
+}
+EXPORT_SYMBOL_GPL(arch_fast_hash2);
+
+static int __init hashlib_init(void)
+{
+	setup_arch_fast_hash(&arch_hash_ops);
+	return 0;
+}
+early_initcall(hashlib_init);

tools/perf/util/include/asm/hash.h

@@ -0,0 +1,6 @@
+#ifndef __ASM_GENERIC_HASH_H
+#define __ASM_GENERIC_HASH_H
+
+/* Stub */
+
+#endif /* __ASM_GENERIC_HASH_H */