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authorLinus Torvalds <torvalds@linux-foundation.org>2012-03-23 19:59:10 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-23 19:59:10 -0400
commit8e3ade251bc7c0a4f0777df4dd34343a03efadba (patch)
tree6c0b78731e3d6609057951d07660efbd90992ad0 /lib/crc32defs.h
parente317234975cb7463b8ca21a93bb6862d9dcf113f (diff)
parente075f59152890ffd7e3d704afc997dd686c8a781 (diff)
Merge branch 'akpm' (Andrew's patch-bomb)
Merge second batch of patches from Andrew Morton: - various misc things - core kernel changes to prctl, exit, exec, init, etc. - kernel/watchdog.c updates - get_maintainer - MAINTAINERS - the backlight driver queue - core bitops code cleanups - the led driver queue - some core prio_tree work - checkpatch udpates - largeish crc32 update - a new poll() feature for the v4l guys - the rtc driver queue - fatfs - ptrace - signals - kmod/usermodehelper updates - coredump - procfs updates * emailed from Andrew Morton <akpm@linux-foundation.org>: (141 commits) seq_file: add seq_set_overflow(), seq_overflow() proc-ns: use d_set_d_op() API to set dentry ops in proc_ns_instantiate(). procfs: speed up /proc/pid/stat, statm procfs: add num_to_str() to speed up /proc/stat proc: speed up /proc/stat handling fs/proc/kcore.c: make get_sparsemem_vmemmap_info() static coredump: add VM_NODUMP, MADV_NODUMP, MADV_CLEAR_NODUMP coredump: remove VM_ALWAYSDUMP flag kmod: make __request_module() killable kmod: introduce call_modprobe() helper usermodehelper: ____call_usermodehelper() doesn't need do_exit() usermodehelper: kill umh_wait, renumber UMH_* constants usermodehelper: implement UMH_KILLABLE usermodehelper: introduce umh_complete(sub_info) usermodehelper: use UMH_WAIT_PROC consistently signal: zap_pid_ns_processes: s/SEND_SIG_NOINFO/SEND_SIG_FORCED/ signal: oom_kill_task: use SEND_SIG_FORCED instead of force_sig() signal: cosmetic, s/from_ancestor_ns/force/ in prepare_signal() paths signal: give SEND_SIG_FORCED more power to beat SIGNAL_UNKILLABLE Hexagon: use set_current_blocked() and block_sigmask() ...
Diffstat (limited to 'lib/crc32defs.h')
-rw-r--r--lib/crc32defs.h56
1 files changed, 48 insertions, 8 deletions
diff --git a/lib/crc32defs.h b/lib/crc32defs.h
index 9b6773d73749..64cba2c3c700 100644
--- a/lib/crc32defs.h
+++ b/lib/crc32defs.h
@@ -6,27 +6,67 @@
6#define CRCPOLY_LE 0xedb88320 6#define CRCPOLY_LE 0xedb88320
7#define CRCPOLY_BE 0x04c11db7 7#define CRCPOLY_BE 0x04c11db7
8 8
9/* How many bits at a time to use. Requires a table of 4<<CRC_xx_BITS bytes. */ 9/*
10/* For less performance-sensitive, use 4 */ 10 * This is the CRC32c polynomial, as outlined by Castagnoli.
11#ifndef CRC_LE_BITS 11 * x^32+x^28+x^27+x^26+x^25+x^23+x^22+x^20+x^19+x^18+x^14+x^13+x^11+x^10+x^9+
12 * x^8+x^6+x^0
13 */
14#define CRC32C_POLY_LE 0x82F63B78
15
16/* Try to choose an implementation variant via Kconfig */
17#ifdef CONFIG_CRC32_SLICEBY8
18# define CRC_LE_BITS 64
19# define CRC_BE_BITS 64
20#endif
21#ifdef CONFIG_CRC32_SLICEBY4
22# define CRC_LE_BITS 32
23# define CRC_BE_BITS 32
24#endif
25#ifdef CONFIG_CRC32_SARWATE
12# define CRC_LE_BITS 8 26# define CRC_LE_BITS 8
27# define CRC_BE_BITS 8
28#endif
29#ifdef CONFIG_CRC32_BIT
30# define CRC_LE_BITS 1
31# define CRC_BE_BITS 1
32#endif
33
34/*
35 * How many bits at a time to use. Valid values are 1, 2, 4, 8, 32 and 64.
36 * For less performance-sensitive, use 4 or 8 to save table size.
37 * For larger systems choose same as CPU architecture as default.
38 * This works well on X86_64, SPARC64 systems. This may require some
39 * elaboration after experiments with other architectures.
40 */
41#ifndef CRC_LE_BITS
42# ifdef CONFIG_64BIT
43# define CRC_LE_BITS 64
44# else
45# define CRC_LE_BITS 32
46# endif
13#endif 47#endif
14#ifndef CRC_BE_BITS 48#ifndef CRC_BE_BITS
15# define CRC_BE_BITS 8 49# ifdef CONFIG_64BIT
50# define CRC_BE_BITS 64
51# else
52# define CRC_BE_BITS 32
53# endif
16#endif 54#endif
17 55
18/* 56/*
19 * Little-endian CRC computation. Used with serial bit streams sent 57 * Little-endian CRC computation. Used with serial bit streams sent
20 * lsbit-first. Be sure to use cpu_to_le32() to append the computed CRC. 58 * lsbit-first. Be sure to use cpu_to_le32() to append the computed CRC.
21 */ 59 */
22#if CRC_LE_BITS > 8 || CRC_LE_BITS < 1 || CRC_LE_BITS & CRC_LE_BITS-1 60#if CRC_LE_BITS > 64 || CRC_LE_BITS < 1 || CRC_LE_BITS == 16 || \
23# error CRC_LE_BITS must be a power of 2 between 1 and 8 61 CRC_LE_BITS & CRC_LE_BITS-1
62# error "CRC_LE_BITS must be one of {1, 2, 4, 8, 32, 64}"
24#endif 63#endif
25 64
26/* 65/*
27 * Big-endian CRC computation. Used with serial bit streams sent 66 * Big-endian CRC computation. Used with serial bit streams sent
28 * msbit-first. Be sure to use cpu_to_be32() to append the computed CRC. 67 * msbit-first. Be sure to use cpu_to_be32() to append the computed CRC.
29 */ 68 */
30#if CRC_BE_BITS > 8 || CRC_BE_BITS < 1 || CRC_BE_BITS & CRC_BE_BITS-1 69#if CRC_BE_BITS > 64 || CRC_BE_BITS < 1 || CRC_BE_BITS == 16 || \
31# error CRC_BE_BITS must be a power of 2 between 1 and 8 70 CRC_BE_BITS & CRC_BE_BITS-1
71# error "CRC_BE_BITS must be one of {1, 2, 4, 8, 32, 64}"
32#endif 72#endif