crc32: bolt on crc32c

[deliverable/linux.git] / lib / crc32.c

diff --git a/lib/crc32.c b/lib/crc32.c
index a1a5145a93ba0a96d8207bdf048e697c50129f61..87678dd1141ed76425687eaf23ff20826a9aa4ca 100644 (file)
--- a/lib/crc32.c
+++ b/lib/crc32.c
@@ -46,7 +46,7 @@
 #include "crc32table.h"
 
 MODULE_AUTHOR("Matt Domsch <Matt_Domsch@dell.com>");
-MODULE_DESCRIPTION("Ethernet CRC32 calculations");
+MODULE_DESCRIPTION("Various CRC32 calculations");
 MODULE_LICENSE("GPL");
 
 #if CRC_LE_BITS > 8 || CRC_BE_BITS > 8
@@ -135,45 +135,66 @@ crc32_body(u32 crc, unsigned char const *buf, size_t len, const u32 (*tab)[256])
  * @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)
+static inline u32 __pure crc32_le_generic(u32 crc, unsigned char const *p,
+                                         size_t len, const u32 (*tab)[256],
+                                         u32 polynomial)
 {
 #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);
+                       crc = (crc >> 1) ^ ((crc & 1) ? polynomial : 0);
        }
 # elif CRC_LE_BITS == 2
        while (len--) {
                crc ^= *p++;
-               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];
+               crc = (crc >> 2) ^ tab[0][crc & 3];
+               crc = (crc >> 2) ^ tab[0][crc & 3];
+               crc = (crc >> 2) ^ tab[0][crc & 3];
+               crc = (crc >> 2) ^ tab[0][crc & 3];
        }
 # elif CRC_LE_BITS == 4
        while (len--) {
                crc ^= *p++;
-               crc = (crc >> 4) ^ crc32table_le[0][crc & 15];
-               crc = (crc >> 4) ^ crc32table_le[0][crc & 15];
+               crc = (crc >> 4) ^ tab[0][crc & 15];
+               crc = (crc >> 4) ^ tab[0][crc & 15];
        }
 # elif CRC_LE_BITS == 8
        /* aka Sarwate algorithm */
        while (len--) {
                crc ^= *p++;
-               crc = (crc >> 8) ^ crc32table_le[0][crc & 255];
+               crc = (crc >> 8) ^ tab[0][crc & 255];
        }
 # else
-       const u32      (*tab)[] = crc32table_le;
-
        crc = (__force u32) __cpu_to_le32(crc);
        crc = crc32_body(crc, p, len, tab);
        crc = __le32_to_cpu((__force __le32)crc);
 #endif
        return crc;
 }
+
+#if CRC_LE_BITS == 1
+u32 __pure crc32_le(u32 crc, unsigned char const *p, size_t len)
+{
+       return crc32_le_generic(crc, p, len, NULL, CRCPOLY_LE);
+}
+u32 __pure __crc32c_le(u32 crc, unsigned char const *p, size_t len)
+{
+       return crc32_le_generic(crc, p, len, NULL, CRC32C_POLY_LE);
+}
+#else
+u32 __pure crc32_le(u32 crc, unsigned char const *p, size_t len)
+{
+       return crc32_le_generic(crc, p, len, crc32table_le, CRCPOLY_LE);
+}
+u32 __pure __crc32c_le(u32 crc, unsigned char const *p, size_t len)
+{
+       return crc32_le_generic(crc, p, len, crc32ctable_le, CRC32C_POLY_LE);
+}
+#endif
 EXPORT_SYMBOL(crc32_le);
+EXPORT_SYMBOL(__crc32c_le);
 
 /**
  * crc32_be() - Calculate bitwise big-endian Ethernet AUTODIN II CRC32
@@ -182,7 +203,9 @@ EXPORT_SYMBOL(crc32_le);
  * @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)
+static inline u32 __pure crc32_be_generic(u32 crc, unsigned char const *p,
+                                         size_t len, const u32 (*tab)[256],
+                                         u32 polynomial)
 {
 #if CRC_BE_BITS == 1
        int i;
@@ -190,37 +213,47 @@ u32 __pure crc32_be(u32 crc, unsigned char const *p, size_t len)
                crc ^= *p++ << 24;
                for (i = 0; i < 8; i++)
                        crc =
-                           (crc << 1) ^ ((crc & 0x80000000) ? CRCPOLY_BE :
+                           (crc << 1) ^ ((crc & 0x80000000) ? polynomial :
                                          0);
        }
 # elif CRC_BE_BITS == 2
        while (len--) {
                crc ^= *p++ << 24;
-               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];
+               crc = (crc << 2) ^ tab[0][crc >> 30];
+               crc = (crc << 2) ^ tab[0][crc >> 30];
+               crc = (crc << 2) ^ tab[0][crc >> 30];
+               crc = (crc << 2) ^ tab[0][crc >> 30];
        }
 # elif CRC_BE_BITS == 4
        while (len--) {
                crc ^= *p++ << 24;
-               crc = (crc << 4) ^ crc32table_be[0][crc >> 28];
-               crc = (crc << 4) ^ crc32table_be[0][crc >> 28];
+               crc = (crc << 4) ^ tab[0][crc >> 28];
+               crc = (crc << 4) ^ tab[0][crc >> 28];
        }
 # elif CRC_BE_BITS == 8
        while (len--) {
                crc ^= *p++ << 24;
-               crc = (crc << 8) ^ crc32table_be[0][crc >> 24];
+               crc = (crc << 8) ^ tab[0][crc >> 24];
        }
 # else
-       const u32      (*tab)[] = crc32table_be;
-
        crc = (__force u32) __cpu_to_be32(crc);
        crc = crc32_body(crc, p, len, tab);
        crc = __be32_to_cpu((__force __be32)crc);
 # endif
        return crc;
 }
+
+#if CRC_LE_BITS == 1
+u32 __pure crc32_be(u32 crc, unsigned char const *p, size_t len)
+{
+       return crc32_be_generic(crc, p, len, NULL, CRCPOLY_BE);
+}
+#else
+u32 __pure crc32_be(u32 crc, unsigned char const *p, size_t len)
+{
+       return crc32_be_generic(crc, p, len, crc32table_be, CRCPOLY_BE);
+}
+#endif
 EXPORT_SYMBOL(crc32_be);
 
 #ifdef CONFIG_CRC32_SELFTEST