diff options
author | Joakim Tjernlund <Joakim.Tjernlund@transmode.se> | 2010-03-05 16:43:55 -0500 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-03-06 14:26:45 -0500 |
commit | 4f2a9463d18517a9839401c3de6419ee1435875b (patch) | |
tree | fa19722c8b1a214ef269cb210f73d9c8a35e88da /lib | |
parent | 5e79d96eed306a8b4af67b3f35f6867edfabeebc (diff) |
crc32: some minor cleanups
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/crc32.c | 30 |
1 files changed, 14 insertions, 16 deletions
diff --git a/lib/crc32.c b/lib/crc32.c index 02e3b31b3a79..0f45fbff34cb 100644 --- a/lib/crc32.c +++ b/lib/crc32.c | |||
@@ -30,11 +30,15 @@ | |||
30 | #include <asm/atomic.h> | 30 | #include <asm/atomic.h> |
31 | #include "crc32defs.h" | 31 | #include "crc32defs.h" |
32 | #if CRC_LE_BITS == 8 | 32 | #if CRC_LE_BITS == 8 |
33 | #define tole(x) __constant_cpu_to_le32(x) | 33 | # define tole(x) __constant_cpu_to_le32(x) |
34 | #define tobe(x) __constant_cpu_to_be32(x) | ||
35 | #else | 34 | #else |
36 | #define tole(x) (x) | 35 | # define tole(x) (x) |
37 | #define tobe(x) (x) | 36 | #endif |
37 | |||
38 | #if CRC_BE_BITS == 8 | ||
39 | # define tobe(x) __constant_cpu_to_be32(x) | ||
40 | #else | ||
41 | # define tobe(x) (x) | ||
38 | #endif | 42 | #endif |
39 | #include "crc32table.h" | 43 | #include "crc32table.h" |
40 | 44 | ||
@@ -52,20 +56,19 @@ crc32_body(u32 crc, unsigned char const *buf, size_t len, const u32 *tab) | |||
52 | # else | 56 | # else |
53 | # define DO_CRC(x) crc = tab[((crc >> 24) ^ (x)) & 255] ^ (crc << 8) | 57 | # define DO_CRC(x) crc = tab[((crc >> 24) ^ (x)) & 255] ^ (crc << 8) |
54 | # endif | 58 | # endif |
55 | const u32 *b = (const u32 *)buf; | 59 | const u32 *b; |
56 | size_t rem_len; | 60 | size_t rem_len; |
57 | 61 | ||
58 | /* Align it */ | 62 | /* Align it */ |
59 | if (unlikely((long)b & 3 && len)) { | 63 | if (unlikely((long)buf & 3 && len)) { |
60 | u8 *p = (u8 *)b; | ||
61 | do { | 64 | do { |
62 | DO_CRC(*p++); | 65 | DO_CRC(*buf++); |
63 | } while ((--len) && ((long)p)&3); | 66 | } while ((--len) && ((long)buf)&3); |
64 | b = (u32 *)p; | ||
65 | } | 67 | } |
66 | rem_len = len & 3; | 68 | rem_len = len & 3; |
67 | /* load data 32 bits wide, xor data 32 bits wide. */ | 69 | /* load data 32 bits wide, xor data 32 bits wide. */ |
68 | len = len >> 2; | 70 | len = len >> 2; |
71 | b = (const u32 *)buf; | ||
69 | for (--b; len; --len) { | 72 | for (--b; len; --len) { |
70 | crc ^= *++b; /* use pre increment for speed */ | 73 | crc ^= *++b; /* use pre increment for speed */ |
71 | DO_CRC(0); | 74 | DO_CRC(0); |
@@ -82,6 +85,7 @@ crc32_body(u32 crc, unsigned char const *buf, size_t len, const u32 *tab) | |||
82 | } while (--len); | 85 | } while (--len); |
83 | } | 86 | } |
84 | return crc; | 87 | return crc; |
88 | #undef DO_CRC | ||
85 | } | 89 | } |
86 | #endif | 90 | #endif |
87 | /** | 91 | /** |
@@ -119,9 +123,6 @@ u32 __pure crc32_le(u32 crc, unsigned char const *p, size_t len) | |||
119 | crc = __cpu_to_le32(crc); | 123 | crc = __cpu_to_le32(crc); |
120 | crc = crc32_body(crc, p, len, tab); | 124 | crc = crc32_body(crc, p, len, tab); |
121 | return __le32_to_cpu(crc); | 125 | return __le32_to_cpu(crc); |
122 | #undef ENDIAN_SHIFT | ||
123 | #undef DO_CRC | ||
124 | |||
125 | # elif CRC_LE_BITS == 4 | 126 | # elif CRC_LE_BITS == 4 |
126 | while (len--) { | 127 | while (len--) { |
127 | crc ^= *p++; | 128 | crc ^= *p++; |
@@ -179,9 +180,6 @@ u32 __pure crc32_be(u32 crc, unsigned char const *p, size_t len) | |||
179 | crc = __cpu_to_be32(crc); | 180 | crc = __cpu_to_be32(crc); |
180 | crc = crc32_body(crc, p, len, tab); | 181 | crc = crc32_body(crc, p, len, tab); |
181 | return __be32_to_cpu(crc); | 182 | return __be32_to_cpu(crc); |
182 | #undef ENDIAN_SHIFT | ||
183 | #undef DO_CRC | ||
184 | |||
185 | # elif CRC_BE_BITS == 4 | 183 | # elif CRC_BE_BITS == 4 |
186 | while (len--) { | 184 | while (len--) { |
187 | crc ^= *p++ << 24; | 185 | crc ^= *p++ << 24; |