Merge branch 'akpm' (updates from Andrew Morton)

Merge second patch-bomb from Andrew Morton:
 - misc fixes
 - audit stuff
 - fanotify/inotify/dnotify things
 - most of the rest of MM.  The new cache shrinker code from Glauber and
   Dave Chinner probably isn't quite stabilized yet.
 - ptrace
 - ipc
 - partitions
 - reboot cleanups
 - add LZ4 decompressor, use it for kernel compression

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
  lib/scatterlist: error handling in __sg_alloc_table()
  scsi_debug: fix do_device_access() with wrap around range
  crypto: talitos: use sg_pcopy_to_buffer()
  lib/scatterlist: introduce sg_pcopy_from_buffer() and sg_pcopy_to_buffer()
  lib/scatterlist: factor out sg_miter_get_next_page() from sg_miter_next()
  crypto: add lz4 Cryptographic API
  lib: add lz4 compressor module
  arm: add support for LZ4-compressed kernel
  lib: add support for LZ4-compressed kernel
  decompressor: add LZ4 decompressor module
  lib: add weak clz/ctz functions
  reboot: move arch/x86 reboot= handling to generic kernel
  reboot: arm: change reboot_mode to use enum reboot_mode
  reboot: arm: prepare reboot_mode for moving to generic kernel code
  reboot: arm: remove unused restart_mode fields from some arm subarchs
  reboot: unicore32: prepare reboot_mode for moving to generic kernel code
  reboot: x86: prepare reboot_mode for moving to generic kernel code
  reboot: checkpatch.pl the new kernel/reboot.c file
  reboot: move shutdown/reboot related functions to kernel/reboot.c
  reboot: remove -stable friendly PF_THREAD_BOUND define
  ...

1 files changed, 443 insertions, 0 deletions

diff --git a/lib/lz4/lz4_compress.c b/lib/lz4/lz4_compress.c
new file mode 100644
index 000000000000..fd94058bd7f9
--- /dev/null
+++ b/lib/lz4/lz4_compress.c
@@ -0,0 +1,443 @@
+/*
+ * LZ4 - Fast LZ compression algorithm
+ * Copyright (C) 2011-2012, Yann Collet.
+ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+
+ * 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.
+ *
+ * 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.
+ *
+ * You can contact the author at :
+ * - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
+ * - LZ4 source repository : http://code.google.com/p/lz4/
+ *
+ *  Changed for kernel use by:
+ *  Chanho Min <chanho.min@lge.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/lz4.h>
+#include <asm/unaligned.h>
+#include "lz4defs.h"
+
+/*
+ * LZ4_compressCtx :
+ * -----------------
+ * Compress 'isize' bytes from 'source' into an output buffer 'dest' of
+ * maximum size 'maxOutputSize'.  * If it cannot achieve it, compression
+ * will stop, and result of the function will be zero.
+ * return : the number of bytes written in buffer 'dest', or 0 if the
+ * compression fails
+ */
+static inline int lz4_compressctx(void *ctx,
+		const char *source,
+		char *dest,
+		int isize,
+		int maxoutputsize)
+{
+	HTYPE *hashtable = (HTYPE *)ctx;
+	const u8 *ip = (u8 *)source;
+#if LZ4_ARCH64
+	const BYTE * const base = ip;
+#else
+	const int base = 0;
+#endif
+	const u8 *anchor = ip;
+	const u8 *const iend = ip + isize;
+	const u8 *const mflimit = iend - MFLIMIT;
+	#define MATCHLIMIT (iend - LASTLITERALS)
+
+	u8 *op = (u8 *) dest;
+	u8 *const oend = op + maxoutputsize;
+	int length;
+	const int skipstrength = SKIPSTRENGTH;
+	u32 forwardh;
+	int lastrun;
+
+	/* Init */
+	if (isize < MINLENGTH)
+		goto _last_literals;
+
+	memset((void *)hashtable, 0, LZ4_MEM_COMPRESS);
+
+	/* First Byte */
+	hashtable[LZ4_HASH_VALUE(ip)] = ip - base;
+	ip++;
+	forwardh = LZ4_HASH_VALUE(ip);
+
+	/* Main Loop */
+	for (;;) {
+		int findmatchattempts = (1U << skipstrength) + 3;
+		const u8 *forwardip = ip;
+		const u8 *ref;
+		u8 *token;
+
+		/* Find a match */
+		do {
+			u32 h = forwardh;
+			int step = findmatchattempts++ >> skipstrength;
+			ip = forwardip;
+			forwardip = ip + step;
+
+			if (unlikely(forwardip > mflimit))
+				goto _last_literals;
+
+			forwardh = LZ4_HASH_VALUE(forwardip);
+			ref = base + hashtable[h];
+			hashtable[h] = ip - base;
+		} while ((ref < ip - MAX_DISTANCE) || (A32(ref) != A32(ip)));
+
+		/* Catch up */
+		while ((ip > anchor) && (ref > (u8 *)source) &&
+			unlikely(ip[-1] == ref[-1])) {
+			ip--;
+			ref--;
+		}
+
+		/* Encode Literal length */
+		length = (int)(ip - anchor);
+		token = op++;
+		/* check output limit */
+		if (unlikely(op + length + (2 + 1 + LASTLITERALS) +
+			(length >> 8) > oend))
+			return 0;
+
+		if (length >= (int)RUN_MASK) {
+			int len;
+			*token = (RUN_MASK << ML_BITS);
+			len = length - RUN_MASK;
+			for (; len > 254 ; len -= 255)
+				*op++ = 255;
+			*op++ = (u8)len;
+		} else
+			*token = (length << ML_BITS);
+
+		/* Copy Literals */
+		LZ4_BLINDCOPY(anchor, op, length);
+_next_match:
+		/* Encode Offset */
+		LZ4_WRITE_LITTLEENDIAN_16(op, (u16)(ip - ref));
+
+		/* Start Counting */
+		ip += MINMATCH;
+		/* MinMatch verified */
+		ref += MINMATCH;
+		anchor = ip;
+		while (likely(ip < MATCHLIMIT - (STEPSIZE - 1))) {
+			#if LZ4_ARCH64
+			u64 diff = A64(ref) ^ A64(ip);
+			#else
+			u32 diff = A32(ref) ^ A32(ip);
+			#endif
+			if (!diff) {
+				ip += STEPSIZE;
+				ref += STEPSIZE;
+				continue;
+			}
+			ip += LZ4_NBCOMMONBYTES(diff);
+			goto _endcount;
+		}
+		#if LZ4_ARCH64
+		if ((ip < (MATCHLIMIT - 3)) && (A32(ref) == A32(ip))) {
+			ip += 4;
+			ref += 4;
+		}
+		#endif
+		if ((ip < (MATCHLIMIT - 1)) && (A16(ref) == A16(ip))) {
+			ip += 2;
+			ref += 2;
+		}
+		if ((ip < MATCHLIMIT) && (*ref == *ip))
+			ip++;
+_endcount:
+		/* Encode MatchLength */
+		length = (int)(ip - anchor);
+		/* Check output limit */
+		if (unlikely(op + (1 + LASTLITERALS) + (length >> 8) > oend))
+			return 0;
+		if (length >= (int)ML_MASK) {
+			*token += ML_MASK;
+			length -= ML_MASK;
+			for (; length > 509 ; length -= 510) {
+				*op++ = 255;
+				*op++ = 255;
+			}
+			if (length > 254) {
+				length -= 255;
+				*op++ = 255;
+			}
+			*op++ = (u8)length;
+		} else
+			*token += length;
+
+		/* Test end of chunk */
+		if (ip > mflimit) {
+			anchor = ip;
+			break;
+		}
+
+		/* Fill table */
+		hashtable[LZ4_HASH_VALUE(ip-2)] = ip - 2 - base;
+
+		/* Test next position */
+		ref = base + hashtable[LZ4_HASH_VALUE(ip)];
+		hashtable[LZ4_HASH_VALUE(ip)] = ip - base;
+		if ((ref > ip - (MAX_DISTANCE + 1)) && (A32(ref) == A32(ip))) {
+			token = op++;
+			*token = 0;
+			goto _next_match;
+		}
+
+		/* Prepare next loop */
+		anchor = ip++;
+		forwardh = LZ4_HASH_VALUE(ip);
+	}
+
+_last_literals:
+	/* Encode Last Literals */
+	lastrun = (int)(iend - anchor);
+	if (((char *)op - dest) + lastrun + 1
+		+ ((lastrun + 255 - RUN_MASK) / 255) > (u32)maxoutputsize)
+		return 0;
+
+	if (lastrun >= (int)RUN_MASK) {
+		*op++ = (RUN_MASK << ML_BITS);
+		lastrun -= RUN_MASK;
+		for (; lastrun > 254 ; lastrun -= 255)
+			*op++ = 255;
+		*op++ = (u8)lastrun;
+	} else
+		*op++ = (lastrun << ML_BITS);
+	memcpy(op, anchor, iend - anchor);
+	op += iend - anchor;
+
+	/* End */
+	return (int)(((char *)op) - dest);
+}
+
+static inline int lz4_compress64kctx(void *ctx,
+		const char *source,
+		char *dest,
+		int isize,
+		int maxoutputsize)
+{
+	u16 *hashtable = (u16 *)ctx;
+	const u8 *ip = (u8 *) source;
+	const u8 *anchor = ip;
+	const u8 *const base = ip;
+	const u8 *const iend = ip + isize;
+	const u8 *const mflimit = iend - MFLIMIT;
+	#define MATCHLIMIT (iend - LASTLITERALS)
+
+	u8 *op = (u8 *) dest;
+	u8 *const oend = op + maxoutputsize;
+	int len, length;
+	const int skipstrength = SKIPSTRENGTH;
+	u32 forwardh;
+	int lastrun;
+
+	/* Init */
+	if (isize < MINLENGTH)
+		goto _last_literals;
+
+	memset((void *)hashtable, 0, LZ4_MEM_COMPRESS);
+
+	/* First Byte */
+	ip++;
+	forwardh = LZ4_HASH64K_VALUE(ip);
+
+	/* Main Loop */
+	for (;;) {
+		int findmatchattempts = (1U << skipstrength) + 3;
+		const u8 *forwardip = ip;
+		const u8 *ref;
+		u8 *token;
+
+		/* Find a match */
+		do {
+			u32 h = forwardh;
+			int step = findmatchattempts++ >> skipstrength;
+			ip = forwardip;
+			forwardip = ip + step;
+
+			if (forwardip > mflimit)
+				goto _last_literals;
+
+			forwardh = LZ4_HASH64K_VALUE(forwardip);
+			ref = base + hashtable[h];
+			hashtable[h] = (u16)(ip - base);
+		} while (A32(ref) != A32(ip));
+
+		/* Catch up */
+		while ((ip > anchor) && (ref > (u8 *)source)
+			&& (ip[-1] == ref[-1])) {
+			ip--;
+			ref--;
+		}
+
+		/* Encode Literal length */
+		length = (int)(ip - anchor);
+		token = op++;
+		/* Check output limit */
+		if (unlikely(op + length + (2 + 1 + LASTLITERALS)
+			+ (length >> 8) > oend))
+			return 0;
+		if (length >= (int)RUN_MASK) {
+			*token = (RUN_MASK << ML_BITS);
+			len = length - RUN_MASK;
+			for (; len > 254 ; len -= 255)
+				*op++ = 255;
+			*op++ = (u8)len;
+		} else
+			*token = (length << ML_BITS);
+
+		/* Copy Literals */
+		LZ4_BLINDCOPY(anchor, op, length);
+
+_next_match:
+		/* Encode Offset */
+		LZ4_WRITE_LITTLEENDIAN_16(op, (u16)(ip - ref));
+
+		/* Start Counting */
+		ip += MINMATCH;
+		/* MinMatch verified */
+		ref += MINMATCH;
+		anchor = ip;
+
+		while (ip < MATCHLIMIT - (STEPSIZE - 1)) {
+			#if LZ4_ARCH64
+			u64 diff = A64(ref) ^ A64(ip);
+			#else
+			u32 diff = A32(ref) ^ A32(ip);
+			#endif
+
+			if (!diff) {
+				ip += STEPSIZE;
+				ref += STEPSIZE;
+				continue;
+			}
+			ip += LZ4_NBCOMMONBYTES(diff);
+			goto _endcount;
+		}
+		#if LZ4_ARCH64
+		if ((ip < (MATCHLIMIT - 3)) && (A32(ref) == A32(ip))) {
+			ip += 4;
+			ref += 4;
+		}
+		#endif
+		if ((ip < (MATCHLIMIT - 1)) && (A16(ref) == A16(ip))) {
+			ip += 2;
+			ref += 2;
+		}
+		if ((ip < MATCHLIMIT) && (*ref == *ip))
+			ip++;
+_endcount:
+
+		/* Encode MatchLength */
+		len = (int)(ip - anchor);
+		/* Check output limit */
+		if (unlikely(op + (1 + LASTLITERALS) + (len >> 8) > oend))
+			return 0;
+		if (len >= (int)ML_MASK) {
+			*token += ML_MASK;
+			len -= ML_MASK;
+			for (; len > 509 ; len -= 510) {
+				*op++ = 255;
+				*op++ = 255;
+			}
+			if (len > 254) {
+				len -= 255;
+				*op++ = 255;
+			}
+			*op++ = (u8)len;
+		} else
+			*token += len;
+
+		/* Test end of chunk */
+		if (ip > mflimit) {
+			anchor = ip;
+			break;
+		}
+
+		/* Fill table */
+		hashtable[LZ4_HASH64K_VALUE(ip-2)] = (u16)(ip - 2 - base);
+
+		/* Test next position */
+		ref = base + hashtable[LZ4_HASH64K_VALUE(ip)];
+		hashtable[LZ4_HASH64K_VALUE(ip)] = (u16)(ip - base);
+		if (A32(ref) == A32(ip)) {
+			token = op++;
+			*token = 0;
+			goto _next_match;
+		}
+
+		/* Prepare next loop */
+		anchor = ip++;
+		forwardh = LZ4_HASH64K_VALUE(ip);
+	}
+
+_last_literals:
+	/* Encode Last Literals */
+	lastrun = (int)(iend - anchor);
+	if (op + lastrun + 1 + (lastrun - RUN_MASK + 255) / 255 > oend)
+		return 0;
+	if (lastrun >= (int)RUN_MASK) {
+		*op++ = (RUN_MASK << ML_BITS);
+		lastrun -= RUN_MASK;
+		for (; lastrun > 254 ; lastrun -= 255)
+			*op++ = 255;
+		*op++ = (u8)lastrun;
+	} else
+		*op++ = (lastrun << ML_BITS);
+	memcpy(op, anchor, iend - anchor);
+	op += iend - anchor;
+	/* End */
+	return (int)(((char *)op) - dest);
+}
+
+int lz4_compress(const unsigned char *src, size_t src_len,
+			unsigned char *dst, size_t *dst_len, void *wrkmem)
+{
+	int ret = -1;
+	int out_len = 0;
+
+	if (src_len < LZ4_64KLIMIT)
+		out_len = lz4_compress64kctx(wrkmem, src, dst, src_len,
+				lz4_compressbound(src_len));
+	else
+		out_len = lz4_compressctx(wrkmem, src, dst, src_len,
+				lz4_compressbound(src_len));
+
+	if (out_len < 0)
+		goto exit;
+
+	*dst_len = out_len;
+
+	return 0;
+exit:
+	return ret;
+}
+EXPORT_SYMBOL_GPL(lz4_compress);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LZ4 compressor");