From: "Darrick J. Wong" Subject: [PATCH 51/51] e2fsck: Refactor crc32_be code Date: Tue, 13 Dec 2011 17:18:53 -0800 Message-ID: <20111214011853.20947.90727.stgit@elm3c44.beaverton.ibm.com> References: <20111214011316.20947.13706.stgit@elm3c44.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Sunil Mushran , Amir Goldstein , Andi Kleen , Mingming Cao , Joel Becker , linux-ext4@vger.kernel.org, Coly Li To: Andreas Dilger , Theodore Tso , "Darrick J. Wong" Return-path: Received: from e8.ny.us.ibm.com ([32.97.182.138]:56181 "EHLO e8.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756300Ab1LNBTA (ORCPT ); Tue, 13 Dec 2011 20:19:00 -0500 Received: from /spool/local by e8.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 13 Dec 2011 20:18:59 -0500 Received: from d01av02.pok.ibm.com (d01av02.pok.ibm.com [9.56.224.216]) by d01relay06.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id pBE1IuWK3444958 for ; Tue, 13 Dec 2011 20:18:57 -0500 Received: from d01av02.pok.ibm.com (loopback [127.0.0.1]) by d01av02.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id pBE1Itoi023249 for ; Tue, 13 Dec 2011 23:18:56 -0200 In-Reply-To: <20111214011316.20947.13706.stgit@elm3c44.beaverton.ibm.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Remove crc32_be in favor of the implementation in libext2fs. Signed-off-by: Darrick J. Wong --- e2fsck/Makefile.in | 38 --- e2fsck/crc32.c | 570 ----------------------------------------------- e2fsck/crc32defs.h | 64 ----- e2fsck/e2fsck.h | 3 e2fsck/gen_crc32table.c | 101 -------- e2fsck/recovery.c | 8 - 6 files changed, 10 insertions(+), 774 deletions(-) delete mode 100644 e2fsck/crc32.c delete mode 100644 e2fsck/crc32defs.h delete mode 100644 e2fsck/gen_crc32table.c diff --git a/e2fsck/Makefile.in b/e2fsck/Makefile.in index b5336a4..26a93cd 100644 --- a/e2fsck/Makefile.in +++ b/e2fsck/Makefile.in @@ -64,7 +64,7 @@ COMPILE_ET=$(top_builddir)/lib/et/compile_et --build-tree # #MCHECK= -DMCHECK -OBJS= crc32.o dict.o unix.o e2fsck.o super.o pass1.o pass1b.o pass2.o \ +OBJS= dict.o unix.o e2fsck.o super.o pass1.o pass1b.o pass2.o \ pass3.o pass4.o pass5.o journal.o badblocks.o util.o dirinfo.o \ dx_dirinfo.o ehandler.o problem.o message.o quota.o recovery.o \ region.o revoke.o ea_refcount.o rehash.o profile.o prof_err.o \ @@ -78,11 +78,9 @@ PROFILED_OBJS= profiled/dict.o profiled/unix.o profiled/e2fsck.o \ profiled/message.o profiled/problem.o profiled/quota.o \ profiled/recovery.o profiled/region.o profiled/revoke.o \ profiled/ea_refcount.o profiled/rehash.o profiled/profile.o \ - profiled/crc32.o profiled/prof_err.o profiled/sigcatcher.o + profiled/prof_err.o profiled/sigcatcher.o SRCS= $(srcdir)/e2fsck.c \ - $(srcdir)/crc32.c \ - $(srcdir)/gen_crc32table.c \ $(srcdir)/dict.c \ $(srcdir)/super.c \ $(srcdir)/pass1.c \ @@ -132,15 +130,6 @@ e2fsck.profiled: $(PROFILED_OBJS) $(PROFILED_DEPLIBS) $(Q) $(LD) $(ALL_LDFLAGS) -g -pg -o e2fsck.profiled $(PROFILED_OBJS) \ $(PROFILED_LIBS) -gen_crc32table: $(srcdir)/gen_crc32table.c - $(E) " CC $@" - $(Q) $(BUILD_CC) $(BUILD_CFLAGS) -o gen_crc32table \ - $(srcdir)/gen_crc32table.c - -crc32table.h: gen_crc32table - $(E) " GEN32TABLE $@" - $(Q) ./gen_crc32table > crc32table.h - tst_sigcatcher: $(srcdir)/sigcatcher.c $(Q) $(CC) $(BUILD_LDFLAGS) $(ALL_CFLAGS) $(RDYNAMIC) \ $(srcdir)/sigcatcher.c -DDEBUG -o tst_sigcatcher @@ -151,10 +140,6 @@ tst_problem: $(srcdir)/problem.c $(srcdir)/problem.h $(LIBEXT2FS) \ $(srcdir)/problem.c -DUNITTEST $(LIBEXT2FS) $(LIBCOM_ERR) \ $(LIBINTL) -tst_crc32: $(srcdir)/crc32.c $(LIBEXT2FS) $(DEPLIBCOM_ERR) - $(Q) $(CC) $(BUILD_LDFLAGS) $(ALL_CFLAGS) -o tst_crc32 $(srcdir)/crc32.c \ - -DUNITTEST $(LIBEXT2FS) $(LIBCOM_ERR) - tst_refcount: ea_refcount.c $(DEPLIBCOM_ERR) $(E) " LD $@" $(Q) $(CC) -o tst_refcount $(srcdir)/ea_refcount.c \ @@ -165,10 +150,9 @@ tst_region: region.c $(DEPLIBCOM_ERR) $(Q) $(CC) -o tst_region $(srcdir)/region.c \ $(ALL_CFLAGS) -DTEST_PROGRAM $(LIBCOM_ERR) -check:: tst_refcount tst_region tst_crc32 tst_problem +check:: tst_refcount tst_region tst_problem LD_LIBRARY_PATH=$(LIB) DYLD_LIBRARY_PATH=$(LIB) ./tst_refcount LD_LIBRARY_PATH=$(LIB) DYLD_LIBRARY_PATH=$(LIB) ./tst_region - LD_LIBRARY_PATH=$(LIB) DYLD_LIBRARY_PATH=$(LIB) ./tst_crc32 LD_LIBRARY_PATH=$(LIB) DYLD_LIBRARY_PATH=$(LIB) ./tst_problem extend: extend.o @@ -265,9 +249,8 @@ uninstall: clean: $(RM) -f $(PROGS) \#* *\# *.s *.o *.a *~ core e2fsck.static \ e2fsck.shared e2fsck.profiled flushb e2fsck.8 \ - tst_problem tst_crc32 tst_region tst_refcount gen_crc32table \ - crc32table.h e2fsck.conf.5 prof_err.c prof_err.h \ - test_profile + tst_problem tst_region tst_refcount e2fsck.conf.5 \ + prof_err.c prof_err.h test_profile $(RM) -rf profiled mostlyclean: clean @@ -288,17 +271,6 @@ e2fsck.o: $(srcdir)/e2fsck.c $(top_builddir)/lib/config.h $(srcdir)/e2fsck.h \ $(srcdir)/profile.h prof_err.h $(top_srcdir)/lib/quota/mkquota.h \ $(top_srcdir)/lib/quota/quota.h $(top_srcdir)/lib/../e2fsck/dict.h \ $(srcdir)/problem.h -crc32.o: $(srcdir)/crc32.c $(top_builddir)/lib/config.h $(srcdir)/e2fsck.h \ - $(top_srcdir)/lib/ext2fs/ext2_fs.h $(top_builddir)/lib/ext2fs/ext2_types.h \ - $(top_srcdir)/lib/ext2fs/ext2fs.h $(top_srcdir)/lib/ext2fs/ext3_extents.h \ - $(top_srcdir)/lib/et/com_err.h $(top_srcdir)/lib/ext2fs/ext2_io.h \ - $(top_builddir)/lib/ext2fs/ext2_err.h \ - $(top_srcdir)/lib/ext2fs/ext2_ext_attr.h $(top_srcdir)/lib/ext2fs/bitops.h \ - $(srcdir)/profile.h prof_err.h $(top_srcdir)/lib/quota/mkquota.h \ - $(top_srcdir)/lib/quota/quota.h $(top_srcdir)/lib/../e2fsck/dict.h \ - $(srcdir)/crc32defs.h crc32table.h -gen_crc32table.o: $(srcdir)/gen_crc32table.c $(top_builddir)/lib/config.h \ - $(srcdir)/crc32defs.h dict.o: $(srcdir)/dict.c $(top_builddir)/lib/config.h $(srcdir)/dict.h super.o: $(srcdir)/super.c $(top_builddir)/lib/config.h $(srcdir)/e2fsck.h \ $(top_srcdir)/lib/ext2fs/ext2_fs.h $(top_builddir)/lib/ext2fs/ext2_types.h \ diff --git a/e2fsck/crc32.c b/e2fsck/crc32.c deleted file mode 100644 index 0497a38..0000000 --- a/e2fsck/crc32.c +++ /dev/null @@ -1,570 +0,0 @@ -/* - * crc32.c --- CRC32 function - * - * Copyright (C) 2008 Theodore Ts'o. - * - * %Begin-Header% - * This file may be redistributed under the terms of the GNU Public - * License. - * %End-Header% - */ - -/* - * Oct 15, 2000 Matt Domsch - * Nicer crc32 functions/docs submitted by linux@horizon.com. Thanks! - * Code was from the public domain, copyright abandoned. Code was - * subsequently included in the kernel, thus was re-licensed under the - * GNU GPL v2. - * - * Oct 12, 2000 Matt Domsch - * Same crc32 function was used in 5 other places in the kernel. - * I made one version, and deleted the others. - * There are various incantations of crc32(). Some use a seed of 0 or ~0. - * Some xor at the end with ~0. The generic crc32() function takes - * seed as an argument, and doesn't xor at the end. Then individual - * users can do whatever they need. - * drivers/net/smc9194.c uses seed ~0, doesn't xor with ~0. - * fs/jffs2 uses seed 0, doesn't xor with ~0. - * fs/partitions/efi.c uses seed ~0, xor's with ~0. - * - * This source code is licensed under the GNU General Public License, - * Version 2. See the file COPYING for more details. - */ - -#include "config.h" -#include -#include -#include -#include - -#ifdef UNITTEST -#undef ENABLE_NLS -#endif -#include "e2fsck.h" - -#include "crc32defs.h" -#if CRC_LE_BITS == 8 -#define tole(x) __constant_cpu_to_le32(x) -#define tobe(x) __constant_cpu_to_be32(x) -#else -#define tole(x) (x) -#define tobe(x) (x) -#endif -#include "crc32table.h" - -#ifdef UNITTEST - -/** - * crc32_le() - Calculate bitwise little-endian Ethernet AUTODIN II CRC32 - * @crc: seed value for computation. ~0 for Ethernet, sometimes 0 for - * other uses, or the previous crc32 value if computing incrementally. - * @p: pointer to buffer over which CRC is run - * @len: length of buffer @p - */ -__u32 crc32_le(__u32 crc, unsigned char const *p, size_t len); - -#if CRC_LE_BITS == 1 -/* - * In fact, the table-based code will work in this case, but it can be - * simplified by inlining the table in ?: form. - */ - -__u32 crc32_le(__u32 crc, unsigned char const *p, size_t len) -{ - int i; - while (len--) { - crc ^= *p++; - for (i = 0; i < 8; i++) - crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0); - } - return crc; -} -#else /* Table-based approach */ - -__u32 crc32_le(__u32 crc, unsigned char const *p, size_t len) -{ -# if CRC_LE_BITS == 8 - const __u32 *b =(__u32 *)p; - const __u32 *tab = crc32table_le; - -# ifdef WORDS_BIGENDIAN -# define DO_CRC(x) crc = tab[ ((crc >> 24) ^ (x)) & 255] ^ (crc<<8) -# else -# define DO_CRC(x) crc = tab[ (crc ^ (x)) & 255 ] ^ (crc>>8) -# endif - - crc = __cpu_to_le32(crc); - /* Align it */ - if(unlikely(((long)b)&3 && len)){ - do { - __u8 *p = (__u8 *)b; - DO_CRC(*p++); - b = (void *)p; - } while ((--len) && ((long)b)&3 ); - } - if(likely(len >= 4)){ - /* load data 32 bits wide, xor data 32 bits wide. */ - size_t save_len = len & 3; - len = len >> 2; - --b; /* use pre increment below(*++b) for speed */ - do { - crc ^= *++b; - DO_CRC(0); - DO_CRC(0); - DO_CRC(0); - DO_CRC(0); - } while (--len); - b++; /* point to next byte(s) */ - len = save_len; - } - /* And the last few bytes */ - if(len){ - do { - __u8 *p = (__u8 *)b; - DO_CRC(*p++); - b = (void *)p; - } while (--len); - } - - return __le32_to_cpu(crc); -#undef ENDIAN_SHIFT -#undef DO_CRC - -# elif CRC_LE_BITS == 4 - while (len--) { - crc ^= *p++; - crc = (crc >> 4) ^ crc32table_le[crc & 15]; - crc = (crc >> 4) ^ crc32table_le[crc & 15]; - } - return crc; -# elif CRC_LE_BITS == 2 - while (len--) { - crc ^= *p++; - crc = (crc >> 2) ^ crc32table_le[crc & 3]; - crc = (crc >> 2) ^ crc32table_le[crc & 3]; - crc = (crc >> 2) ^ crc32table_le[crc & 3]; - crc = (crc >> 2) ^ crc32table_le[crc & 3]; - } - return crc; -# endif -} -#endif - -#endif /* UNITTEST */ - -/** - * crc32_be() - Calculate bitwise big-endian Ethernet AUTODIN II CRC32 - * @crc: seed value for computation. ~0 for Ethernet, sometimes 0 for - * other uses, or the previous crc32 value if computing incrementally. - * @p: pointer to buffer over which CRC is run - * @len: length of buffer @p - */ -__u32 crc32_be(__u32 crc, unsigned char const *p, size_t len); - -#if CRC_BE_BITS == 1 -/* - * In fact, the table-based code will work in this case, but it can be - * simplified by inlining the table in ?: form. - */ - -__u32 crc32_be(__u32 crc, unsigned char const *p, size_t len) -{ - int i; - while (len--) { - crc ^= *p++ << 24; - for (i = 0; i < 8; i++) - crc = - (crc << 1) ^ ((crc & 0x80000000) ? CRCPOLY_BE : - 0); - } - return crc; -} - -#else /* Table-based approach */ -__u32 crc32_be(__u32 crc, unsigned char const *p, size_t len) -{ -# if CRC_BE_BITS == 8 - const __u32 *b =(const __u32 *)p; - const __u32 *tab = crc32table_be; - -# ifdef WORDS_BIGENDIAN -# define DO_CRC(x) crc = tab[ ((crc >> 24) ^ (x)) & 255] ^ (crc<<8) -# else -# define DO_CRC(x) crc = tab[ (crc ^ (x)) & 255 ] ^ (crc>>8) -# endif - - crc = __cpu_to_be32(crc); - /* Align it */ - if(unlikely(((long)b)&3 && len)){ - do { - const __u8 *q = (const __u8 *)b; - DO_CRC(*q++); - b = (const __u32 *)q; - } while ((--len) && ((long)b)&3 ); - } - if(likely(len >= 4)){ - /* load data 32 bits wide, xor data 32 bits wide. */ - size_t save_len = len & 3; - len = len >> 2; - --b; /* use pre increment below(*++b) for speed */ - do { - crc ^= *++b; - DO_CRC(0); - DO_CRC(0); - DO_CRC(0); - DO_CRC(0); - } while (--len); - b++; /* point to next byte(s) */ - len = save_len; - } - /* And the last few bytes */ - if(len){ - do { - const __u8 *q = (const __u8 *)b; - DO_CRC(*q++); - b = (const void *)q; - } while (--len); - } - return __be32_to_cpu(crc); -#undef ENDIAN_SHIFT -#undef DO_CRC - -# elif CRC_BE_BITS == 4 - while (len--) { - crc ^= *p++ << 24; - crc = (crc << 4) ^ crc32table_be[crc >> 28]; - crc = (crc << 4) ^ crc32table_be[crc >> 28]; - } - return crc; -# elif CRC_BE_BITS == 2 - while (len--) { - crc ^= *p++ << 24; - crc = (crc << 2) ^ crc32table_be[crc >> 30]; - crc = (crc << 2) ^ crc32table_be[crc >> 30]; - crc = (crc << 2) ^ crc32table_be[crc >> 30]; - crc = (crc << 2) ^ crc32table_be[crc >> 30]; - } - return crc; -# endif -} -#endif - -/* - * A brief CRC tutorial. - * - * A CRC is a long-division remainder. You add the CRC to the message, - * and the whole thing (message+CRC) is a multiple of the given - * CRC polynomial. To check the CRC, you can either check that the - * CRC matches the recomputed value, *or* you can check that the - * remainder computed on the message+CRC is 0. This latter approach - * is used by a lot of hardware implementations, and is why so many - * protocols put the end-of-frame flag after the CRC. - * - * It's actually the same long division you learned in school, except that - * - We're working in binary, so the digits are only 0 and 1, and - * - When dividing polynomials, there are no carries. Rather than add and - * subtract, we just xor. Thus, we tend to get a bit sloppy about - * the difference between adding and subtracting. - * - * A 32-bit CRC polynomial is actually 33 bits long. But since it's - * 33 bits long, bit 32 is always going to be set, so usually the CRC - * is written in hex with the most significant bit omitted. (If you're - * familiar with the IEEE 754 floating-point format, it's the same idea.) - * - * Note that a CRC is computed over a string of *bits*, so you have - * to decide on the endianness of the bits within each byte. To get - * the best error-detecting properties, this should correspond to the - * order they're actually sent. For example, standard RS-232 serial is - * little-endian; the most significant bit (sometimes used for parity) - * is sent last. And when appending a CRC word to a message, you should - * do it in the right order, matching the endianness. - * - * Just like with ordinary division, the remainder is always smaller than - * the divisor (the CRC polynomial) you're dividing by. Each step of the - * division, you take one more digit (bit) of the dividend and append it - * to the current remainder. Then you figure out the appropriate multiple - * of the divisor to subtract to being the remainder back into range. - * In binary, it's easy - it has to be either 0 or 1, and to make the - * XOR cancel, it's just a copy of bit 32 of the remainder. - * - * When computing a CRC, we don't care about the quotient, so we can - * throw the quotient bit away, but subtract the appropriate multiple of - * the polynomial from the remainder and we're back to where we started, - * ready to process the next bit. - * - * A big-endian CRC written this way would be coded like: - * for (i = 0; i < input_bits; i++) { - * multiple = remainder & 0x80000000 ? CRCPOLY : 0; - * remainder = (remainder << 1 | next_input_bit()) ^ multiple; - * } - * Notice how, to get at bit 32 of the shifted remainder, we look - * at bit 31 of the remainder *before* shifting it. - * - * But also notice how the next_input_bit() bits we're shifting into - * the remainder don't actually affect any decision-making until - * 32 bits later. Thus, the first 32 cycles of this are pretty boring. - * Also, to add the CRC to a message, we need a 32-bit-long hole for it at - * the end, so we have to add 32 extra cycles shifting in zeros at the - * end of every message, - * - * So the standard trick is to rearrage merging in the next_input_bit() - * until the moment it's needed. Then the first 32 cycles can be precomputed, - * and merging in the final 32 zero bits to make room for the CRC can be - * skipped entirely. - * This changes the code to: - * for (i = 0; i < input_bits; i++) { - * remainder ^= next_input_bit() << 31; - * multiple = (remainder & 0x80000000) ? CRCPOLY : 0; - * remainder = (remainder << 1) ^ multiple; - * } - * With this optimization, the little-endian code is simpler: - * for (i = 0; i < input_bits; i++) { - * remainder ^= next_input_bit(); - * multiple = (remainder & 1) ? CRCPOLY : 0; - * remainder = (remainder >> 1) ^ multiple; - * } - * - * Note that the other details of endianness have been hidden in CRCPOLY - * (which must be bit-reversed) and next_input_bit(). - * - * However, as long as next_input_bit is returning the bits in a sensible - * order, we can actually do the merging 8 or more bits at a time rather - * than one bit at a time: - * for (i = 0; i < input_bytes; i++) { - * remainder ^= next_input_byte() << 24; - * for (j = 0; j < 8; j++) { - * multiple = (remainder & 0x80000000) ? CRCPOLY : 0; - * remainder = (remainder << 1) ^ multiple; - * } - * } - * Or in little-endian: - * for (i = 0; i < input_bytes; i++) { - * remainder ^= next_input_byte(); - * for (j = 0; j < 8; j++) { - * multiple = (remainder & 1) ? CRCPOLY : 0; - * remainder = (remainder << 1) ^ multiple; - * } - * } - * If the input is a multiple of 32 bits, you can even XOR in a 32-bit - * word at a time and increase the inner loop count to 32. - * - * You can also mix and match the two loop styles, for example doing the - * bulk of a message byte-at-a-time and adding bit-at-a-time processing - * for any fractional bytes at the end. - * - * The only remaining optimization is to the byte-at-a-time table method. - * Here, rather than just shifting one bit of the remainder to decide - * in the correct multiple to subtract, we can shift a byte at a time. - * This produces a 40-bit (rather than a 33-bit) intermediate remainder, - * but again the multiple of the polynomial to subtract depends only on - * the high bits, the high 8 bits in this case. - * - * The multiple we need in that case is the low 32 bits of a 40-bit - * value whose high 8 bits are given, and which is a multiple of the - * generator polynomial. This is simply the CRC-32 of the given - * one-byte message. - * - * Two more details: normally, appending zero bits to a message which - * is already a multiple of a polynomial produces a larger multiple of that - * polynomial. To enable a CRC to detect this condition, it's common to - * invert the CRC before appending it. This makes the remainder of the - * message+crc come out not as zero, but some fixed non-zero value. - * - * The same problem applies to zero bits prepended to the message, and - * a similar solution is used. Instead of starting with a remainder of - * 0, an initial remainder of all ones is used. As long as you start - * the same way on decoding, it doesn't make a difference. - */ - -#ifdef UNITTEST - -#include -#include - -const __u8 byte_rev_table[256] = { - 0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0, - 0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0, - 0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8, - 0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8, - 0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4, - 0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4, - 0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec, - 0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc, - 0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2, - 0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2, - 0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea, - 0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa, - 0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6, - 0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6, - 0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee, - 0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe, - 0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1, - 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1, - 0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9, - 0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9, - 0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5, - 0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5, - 0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed, - 0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd, - 0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3, - 0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3, - 0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb, - 0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb, - 0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7, - 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7, - 0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef, - 0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff, -}; - -static inline __u8 bitrev8(__u8 byte) -{ - return byte_rev_table[byte]; -} - -static inline __u16 bitrev16(__u16 x) -{ - return (bitrev8(x & 0xff) << 8) | bitrev8(x >> 8); -} - -/** - * bitrev32 - reverse the order of bits in a u32 value - * @x: value to be bit-reversed - */ -static __u32 bitrev32(__u32 x) -{ - return (bitrev16(x & 0xffff) << 16) | bitrev16(x >> 16); -} - -#if 0 /*Not used at present */ - -static void -buf_dump(char const *prefix, unsigned char const *buf, size_t len) -{ - fputs(prefix, stdout); - while (len--) - printf(" %02x", *buf++); - putchar('\n'); - -} -#endif - -static void bytereverse(unsigned char *buf, size_t len) -{ - while (len--) { - unsigned char x = bitrev8(*buf); - *buf++ = x; - } -} - -static void random_garbage(unsigned char *buf, size_t len) -{ - while (len--) - *buf++ = (unsigned char) random(); -} - -#if 0 /* Not used at present */ -static void store_le(__u32 x, unsigned char *buf) -{ - buf[0] = (unsigned char) x; - buf[1] = (unsigned char) (x >> 8); - buf[2] = (unsigned char) (x >> 16); - buf[3] = (unsigned char) (x >> 24); -} -#endif - -static void store_be(__u32 x, unsigned char *buf) -{ - buf[0] = (unsigned char) (x >> 24); - buf[1] = (unsigned char) (x >> 16); - buf[2] = (unsigned char) (x >> 8); - buf[3] = (unsigned char) x; -} - -/* - * This checks that CRC(buf + CRC(buf)) = 0, and that - * CRC commutes with bit-reversal. This has the side effect - * of bytewise bit-reversing the input buffer, and returns - * the CRC of the reversed buffer. - */ -static __u32 test_step(__u32 init, unsigned char *buf, size_t len) -{ - __u32 crc1, crc2; - size_t i; - - crc1 = crc32_be(init, buf, len); - store_be(crc1, buf + len); - crc2 = crc32_be(init, buf, len + 4); - if (crc2) - printf("\nCRC cancellation fail: 0x%08x should be 0\n", - crc2); - - for (i = 0; i <= len + 4; i++) { - crc2 = crc32_be(init, buf, i); - crc2 = crc32_be(crc2, buf + i, len + 4 - i); - if (crc2) - printf("\nCRC split fail: 0x%08x\n", crc2); - } - - /* Now swap it around for the other test */ - - bytereverse(buf, len + 4); - init = bitrev32(init); - crc2 = bitrev32(crc1); - if (crc1 != bitrev32(crc2)) - printf("\nBit reversal fail: 0x%08x -> 0x%08x -> 0x%08x\n", - crc1, crc2, bitrev32(crc2)); - crc1 = crc32_le(init, buf, len); - if (crc1 != crc2) - printf("\nCRC endianness fail: 0x%08x != 0x%08x\n", crc1, - crc2); - crc2 = crc32_le(init, buf, len + 4); - if (crc2) - printf("\nCRC cancellation fail: 0x%08x should be 0\n", - crc2); - - for (i = 0; i <= len + 4; i++) { - crc2 = crc32_le(init, buf, i); - crc2 = crc32_le(crc2, buf + i, len + 4 - i); - if (crc2) - printf("\nCRC split fail: 0x%08x\n", crc2); - } - - return crc1; -} - -#define SIZE 64 -#define INIT1 0 -#define INIT2 0 - -int main(int argc, char **argv) -{ - unsigned char buf1[SIZE + 4]; - unsigned char buf2[SIZE + 4]; - unsigned char buf3[SIZE + 4]; - int i, j; - __u32 crc1, crc2, crc3; - int exit_status = 0; - - for (i = 0; i <= SIZE; i++) { - printf("\rTesting length %d...", i); - fflush(stdout); - random_garbage(buf1, i); - random_garbage(buf2, i); - for (j = 0; j < i; j++) - buf3[j] = buf1[j] ^ buf2[j]; - - crc1 = test_step(INIT1, buf1, i); - crc2 = test_step(INIT2, buf2, i); - /* Now check that CRC(buf1 ^ buf2) = CRC(buf1) ^ CRC(buf2) */ - crc3 = test_step(INIT1 ^ INIT2, buf3, i); - if (crc3 != (crc1 ^ crc2)) { - printf("CRC XOR fail: 0x%08x != 0x%08x ^ 0x%08x\n", - crc3, crc1, crc2); - exit_status++; - } - } - printf("\nAll test complete. No failures expected.\n"); - return 0; -} - -#endif /* UNITTEST */ diff --git a/e2fsck/crc32defs.h b/e2fsck/crc32defs.h deleted file mode 100644 index 27414d2..0000000 --- a/e2fsck/crc32defs.h +++ /dev/null @@ -1,64 +0,0 @@ -/* - * There are multiple 16-bit CRC polynomials in common use, but this is - * *the* standard CRC-32 polynomial, first popularized by Ethernet. - * x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x^1+x^0 - */ -#define CRCPOLY_LE 0xedb88320 -#define CRCPOLY_BE 0x04c11db7 - -/* How many bits at a time to use. Requires a table of 4< 8 || CRC_LE_BITS < 1 || CRC_LE_BITS & CRC_LE_BITS-1 -# error CRC_LE_BITS must be a power of 2 between 1 and 8 -#endif - -/* - * Big-endian CRC computation. Used with serial bit streams sent - * msbit-first. Be sure to use cpu_to_be32() to append the computed CRC. - */ -#if CRC_BE_BITS > 8 || CRC_BE_BITS < 1 || CRC_BE_BITS & CRC_BE_BITS-1 -# error CRC_BE_BITS must be a power of 2 between 1 and 8 -#endif - -#define ___constant_swab32(x) \ - ((__u32)( \ - (((__u32)(x) & (__u32)0x000000ffUL) << 24) | \ - (((__u32)(x) & (__u32)0x0000ff00UL) << 8) | \ - (((__u32)(x) & (__u32)0x00ff0000UL) >> 8) | \ - (((__u32)(x) & (__u32)0xff000000UL) >> 24) )) - - -#ifdef WORDS_BIGENDIAN -#define __constant_cpu_to_le32(x) ___constant_swab32((x)) -#define __constant_cpu_to_be32(x) (x) -#define __be32_to_cpu(x) (x) -#define __cpu_to_be32(x) (x) -#define __cpu_to_le32(x) (ext2fs_swab32((x))) -#define __le32_to_cpu(x) (ext2fs_swab32((x))) -#else -#define __constant_cpu_to_le32(x) (x) -#define __constant_cpu_to_be32(x) ___constant_swab32((x)) -#define __be32_to_cpu(x) (ext2fs_swab32((x))) -#define __cpu_to_be32(x) (ext2fs_swab32((x))) -#define __cpu_to_le32(x) (x) -#define __le32_to_cpu(x) (x) -#endif - -#if (__GNUC__ >= 3) -#define likely(x) __builtin_expect(!!(x), 1) -#define unlikely(x) __builtin_expect(!!(x), 0) -#else -#define likely(x) (x) -#define unlikely(x) (x) -#endif diff --git a/e2fsck/e2fsck.h b/e2fsck/e2fsck.h index 96a0cc9..d0249cb 100644 --- a/e2fsck/e2fsck.h +++ b/e2fsck/e2fsck.h @@ -397,9 +397,6 @@ extern int e2fsck_run(e2fsck_t ctx); extern void read_bad_blocks_file(e2fsck_t ctx, const char *bad_blocks_file, int replace_bad_blocks); -/* crc32.c */ -extern __u32 crc32_be(__u32 crc, unsigned char const *p, size_t len); - /* dirinfo.c */ extern void e2fsck_add_dir_info(e2fsck_t ctx, ext2_ino_t ino, ext2_ino_t parent); extern void e2fsck_free_dir_info(e2fsck_t ctx); diff --git a/e2fsck/gen_crc32table.c b/e2fsck/gen_crc32table.c deleted file mode 100644 index 2c1aa8e..0000000 --- a/e2fsck/gen_crc32table.c +++ /dev/null @@ -1,101 +0,0 @@ -/* - * gen_crc32table.c --- Generate CRC32 tables. - * - * Copyright (C) 2008 Theodore Ts'o. - * - * %Begin-Header% - * This file may be redistributed under the terms of the GNU Public - * License. - * %End-Header% - */ - -#include -#include "crc32defs.h" -#include - -#define ENTRIES_PER_LINE 4 - -#define LE_TABLE_SIZE (1 << CRC_LE_BITS) -#define BE_TABLE_SIZE (1 << CRC_BE_BITS) - -static uint32_t crc32table_le[LE_TABLE_SIZE]; -static uint32_t crc32table_be[BE_TABLE_SIZE]; - -/** - * crc32init_le() - allocate and initialize LE table data - * - * crc is the crc of the byte i; other entries are filled in based on the - * fact that crctable[i^j] = crctable[i] ^ crctable[j]. - * - */ -static void crc32init_le(void) -{ - unsigned i, j; - uint32_t crc = 1; - - crc32table_le[0] = 0; - - for (i = 1 << (CRC_LE_BITS - 1); i; i >>= 1) { - crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0); - for (j = 0; j < LE_TABLE_SIZE; j += 2 * i) - crc32table_le[i + j] = crc ^ crc32table_le[j]; - } -} - -/** - * crc32init_be() - allocate and initialize BE table data - */ -static void crc32init_be(void) -{ - unsigned i, j; - uint32_t crc = 0x80000000; - - crc32table_be[0] = 0; - - for (i = 1; i < BE_TABLE_SIZE; i <<= 1) { - crc = (crc << 1) ^ ((crc & 0x80000000) ? CRCPOLY_BE : 0); - for (j = 0; j < i; j++) - crc32table_be[i + j] = crc ^ crc32table_be[j]; - } -} - -static void output_table(uint32_t table[], int len, const char *trans) -{ - int i; - - for (i = 0; i < len - 1; i++) { - if (i % ENTRIES_PER_LINE == 0) - printf("\n"); - printf("%s(0x%8.8xL), ", trans, table[i]); - } - printf("%s(0x%8.8xL)\n", trans, table[len - 1]); -} - -#ifdef __GNUC__ -#define ATTR(x) __attribute__(x) -#else -#define ATTR(x) -#endif - -int main(int argc ATTR((unused)), char** argv ATTR((unused))) -{ - printf("/* this file is generated - do not edit */\n\n"); - - printf("#ifdef UNITTEST\n"); - if (CRC_LE_BITS > 1) { - crc32init_le(); - printf("static const __u32 crc32table_le[] = {"); - output_table(crc32table_le, LE_TABLE_SIZE, "tole"); - printf("};\n"); - } - printf("#endif /* UNITTEST */\n"); - - if (CRC_BE_BITS > 1) { - crc32init_be(); - printf("static const __u32 crc32table_be[] = {"); - output_table(crc32table_be, BE_TABLE_SIZE, "tobe"); - printf("};\n"); - } - - return 0; -} diff --git a/e2fsck/recovery.c b/e2fsck/recovery.c index d7c470e..4a8d850 100644 --- a/e2fsck/recovery.c +++ b/e2fsck/recovery.c @@ -356,7 +356,8 @@ static int calc_chksums(journal_t *journal, struct buffer_head *bh, num_blks = count_tags(journal, bh); /* Calculate checksum of the descriptor block. */ - *crc32_sum = crc32_be(*crc32_sum, (void *)bh->b_data, bh->b_size); + *crc32_sum = ext2fs_crc32_be(*crc32_sum, (void *)bh->b_data, + bh->b_size); for (i = 0; i < num_blks; i++) { io_block = (*next_log_block)++; @@ -367,8 +368,9 @@ static int calc_chksums(journal_t *journal, struct buffer_head *bh, "%lu in log\n", err, io_block); return 1; } else { - *crc32_sum = crc32_be(*crc32_sum, (void *)obh->b_data, - obh->b_size); + *crc32_sum = ext2fs_crc32_be(*crc32_sum, + (void *)obh->b_data, + obh->b_size); } brelse(obh); }