crc32: misc-cleanup.diff

PATCH Superseded Bob Pearson 1 participant 1 message Aug 9, 2011 Library code

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Bob Pearson

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2011-08-09 05:21 UTC #0 lore raw

PATCH v3 3/7 crc32: misc-cleanup.diff

Misc cleanup of lib/crc32.c
- removed unnecessary header files. If it passes sparse without it I took it out.
- straightened out some convoluted ifdef's
- code incorrectly referenced 2D crc32table_le table as crc32table_l(b)e[x] instead of crc32table_l(b)e[0][x] for BITS = 2 & 4. This failed sparse.
- a few trivial whitespace changes

Signed-off-by Bob Pearson <[email protected]>

---
 lib/crc32.c |  104 ++++++++++++++++++++----------------------------------------
 1 file changed, 36 insertions(+), 68 deletions(-)

lib/crc32.c +36 ~~-68~~

Index: infiniband/lib/crc32.c
===================================================================
@@ -21,13 +21,10 @@
  */
 
 #include <linux/crc32.h>
-#include <linux/kernel.h>
 #include <linux/module.h>
-#include <linux/compiler.h>
 #include <linux/types.h>
-#include <linux/init.h>
-#include <asm/atomic.h>
 #include "crc32defs.h"
+
 #if CRC_LE_BITS == 8
 # define tole(x) __constant_cpu_to_le32(x)
 #else

@@ -39,6 +36,7 @@
 #else
 # define tobe(x) (x)
 #endif
+
 #include "crc32table.h"
 
 MODULE_AUTHOR("Matt Domsch <[email protected]>");

@@ -93,6 +91,7 @@ crc32_body(u32 crc, unsigned char const
 #undef DO_CRC4
 }
 #endif
+
 /**
  * crc32_le() - Calculate bitwise little-endian Ethernet AUTODIN II CRC32
  * @crc: seed value for computation.  ~0 for Ethernet, sometimes 0 for

@@ -100,53 +99,39 @@ crc32_body(u32 crc, unsigned char const
  * @p: pointer to buffer over which CRC is run
  * @len: length of buffer @p
  */
-u32 __pure 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 __pure crc32_le(u32 crc, unsigned char const *p, size_t len)
 {
+#if CRC_LE_BITS == 1
 	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 __pure crc32_le(u32 crc, unsigned char const *p, size_t len)
-{
-# if CRC_LE_BITS == 8
-	const u32      (*tab)[] = crc32table_le;
-
-	crc = __cpu_to_le32(crc);
-	crc = crc32_body(crc, p, len, tab);
-	return __le32_to_cpu(crc);
-# elif CRC_LE_BITS == 4
+# elif CRC_LE_BITS == 2
 	while (len--) {
 		crc ^= *p++;
-		crc = (crc >> 4) ^ crc32table_le[crc & 15];
-		crc = (crc >> 4) ^ crc32table_le[crc & 15];
+		crc = (crc >> 2) ^ crc32table_le[0][crc & 3];
+		crc = (crc >> 2) ^ crc32table_le[0][crc & 3];
+		crc = (crc >> 2) ^ crc32table_le[0][crc & 3];
+		crc = (crc >> 2) ^ crc32table_le[0][crc & 3];
 	}
-	return crc;
-# elif CRC_LE_BITS == 2
+# elif CRC_LE_BITS == 4
 	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];
+		crc = (crc >> 4) ^ crc32table_le[0][crc & 15];
+		crc = (crc >> 4) ^ crc32table_le[0][crc & 15];
 	}
+# elif CRC_LE_BITS == 8
+	const u32      (*tab)[] = crc32table_le;
+
+	crc = __cpu_to_le32(crc);
+	crc = crc32_body(crc, p, len, tab);
+	crc = __le32_to_cpu(crc);
+#endif
 	return crc;
-# endif
 }
-#endif
+EXPORT_SYMBOL(crc32_le);
 
 /**
  * crc32_be() - Calculate bitwise big-endian Ethernet AUTODIN II CRC32

@@ -155,16 +140,9 @@ u32 __pure crc32_le(u32 crc, unsigned ch
  * @p: pointer to buffer over which CRC is run
  * @len: length of buffer @p
  */
-u32 __pure 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 __pure crc32_be(u32 crc, unsigned char const *p, size_t len)
 {
+#if CRC_BE_BITS == 1
 	int i;
 	while (len--) {
 		crc ^= *p++ << 24;

@@ -173,39 +151,29 @@ u32 __pure crc32_be(u32 crc, unsigned ch
 			    (crc << 1) ^ ((crc & 0x80000000) ? CRCPOLY_BE :
 					  0);
 	}
-	return crc;
-}
-
-#else				/* Table-based approach */
-u32 __pure crc32_be(u32 crc, unsigned char const *p, size_t len)
-{
-# if CRC_BE_BITS == 8
-	const u32      (*tab)[] = crc32table_be;
-
-	crc = __cpu_to_be32(crc);
-	crc = crc32_body(crc, p, len, tab);
-	return __be32_to_cpu(crc);
-# elif CRC_BE_BITS == 4
+# elif CRC_BE_BITS == 2
 	while (len--) {
 		crc ^= *p++ << 24;
-		crc = (crc << 4) ^ crc32table_be[crc >> 28];
-		crc = (crc << 4) ^ crc32table_be[crc >> 28];
+		crc = (crc << 2) ^ crc32table_be[0][crc >> 30];
+		crc = (crc << 2) ^ crc32table_be[0][crc >> 30];
+		crc = (crc << 2) ^ crc32table_be[0][crc >> 30];
+		crc = (crc << 2) ^ crc32table_be[0][crc >> 30];
 	}
-	return crc;
-# elif CRC_BE_BITS == 2
+# elif CRC_BE_BITS == 4
 	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];
+		crc = (crc << 4) ^ crc32table_be[0][crc >> 28];
+		crc = (crc << 4) ^ crc32table_be[0][crc >> 28];
 	}
-	return crc;
+# elif CRC_BE_BITS == 8
+	const u32      (*tab)[] = crc32table_be;
+
+	crc = __cpu_to_be32(crc);
+	crc = crc32_body(crc, p, len, tab);
+	crc = __be32_to_cpu(crc);
 # endif
+	return crc;
 }
-#endif
-
-EXPORT_SYMBOL(crc32_le);
 EXPORT_SYMBOL(crc32_be);
 
 #ifdef CONFIG_CRC32_SELFTEST