Reinstate "crypto: crct10dif - Wrap crc_t10dif function all to use crypto transform framework"

This patch reinstates commits
	67822649d7305caf3dd50ed46c27b99c94eff996
	39761214eefc6b070f29402aa1165f24d789b3f7
	0b95a7f85718adcbba36407ef88bba0a7379ed03
	31d939625a9a20b1badd2d4e6bf6fd39fa523405
	2d31e518a42828df7877bca23a958627d60408bc

Now that module softdeps are in the kernel we can use that to resolve
the boot issue which cause the revert.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/lib/crc-t10dif.c b/lib/crc-t10dif.c
index fbbd66e..43bc5b0 100644
--- a/lib/crc-t10dif.c
+++ b/lib/crc-t10dif.c
@@ -11,57 +11,45 @@
 #include <linux/types.h>
 #include <linux/module.h>
 #include <linux/crc-t10dif.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <crypto/hash.h>
 
-/* Table generated using the following polynomium:
- * x^16 + x^15 + x^11 + x^9 + x^8 + x^7 + x^5 + x^4 + x^2 + x + 1
- * gt: 0x8bb7
- */
-static const __u16 t10_dif_crc_table[256] = {
-	0x0000, 0x8BB7, 0x9CD9, 0x176E, 0xB205, 0x39B2, 0x2EDC, 0xA56B,
-	0xEFBD, 0x640A, 0x7364, 0xF8D3, 0x5DB8, 0xD60F, 0xC161, 0x4AD6,
-	0x54CD, 0xDF7A, 0xC814, 0x43A3, 0xE6C8, 0x6D7F, 0x7A11, 0xF1A6,
-	0xBB70, 0x30C7, 0x27A9, 0xAC1E, 0x0975, 0x82C2, 0x95AC, 0x1E1B,
-	0xA99A, 0x222D, 0x3543, 0xBEF4, 0x1B9F, 0x9028, 0x8746, 0x0CF1,
-	0x4627, 0xCD90, 0xDAFE, 0x5149, 0xF422, 0x7F95, 0x68FB, 0xE34C,
-	0xFD57, 0x76E0, 0x618E, 0xEA39, 0x4F52, 0xC4E5, 0xD38B, 0x583C,
-	0x12EA, 0x995D, 0x8E33, 0x0584, 0xA0EF, 0x2B58, 0x3C36, 0xB781,
-	0xD883, 0x5334, 0x445A, 0xCFED, 0x6A86, 0xE131, 0xF65F, 0x7DE8,
-	0x373E, 0xBC89, 0xABE7, 0x2050, 0x853B, 0x0E8C, 0x19E2, 0x9255,
-	0x8C4E, 0x07F9, 0x1097, 0x9B20, 0x3E4B, 0xB5FC, 0xA292, 0x2925,
-	0x63F3, 0xE844, 0xFF2A, 0x749D, 0xD1F6, 0x5A41, 0x4D2F, 0xC698,
-	0x7119, 0xFAAE, 0xEDC0, 0x6677, 0xC31C, 0x48AB, 0x5FC5, 0xD472,
-	0x9EA4, 0x1513, 0x027D, 0x89CA, 0x2CA1, 0xA716, 0xB078, 0x3BCF,
-	0x25D4, 0xAE63, 0xB90D, 0x32BA, 0x97D1, 0x1C66, 0x0B08, 0x80BF,
-	0xCA69, 0x41DE, 0x56B0, 0xDD07, 0x786C, 0xF3DB, 0xE4B5, 0x6F02,
-	0x3AB1, 0xB106, 0xA668, 0x2DDF, 0x88B4, 0x0303, 0x146D, 0x9FDA,
-	0xD50C, 0x5EBB, 0x49D5, 0xC262, 0x6709, 0xECBE, 0xFBD0, 0x7067,
-	0x6E7C, 0xE5CB, 0xF2A5, 0x7912, 0xDC79, 0x57CE, 0x40A0, 0xCB17,
-	0x81C1, 0x0A76, 0x1D18, 0x96AF, 0x33C4, 0xB873, 0xAF1D, 0x24AA,
-	0x932B, 0x189C, 0x0FF2, 0x8445, 0x212E, 0xAA99, 0xBDF7, 0x3640,
-	0x7C96, 0xF721, 0xE04F, 0x6BF8, 0xCE93, 0x4524, 0x524A, 0xD9FD,
-	0xC7E6, 0x4C51, 0x5B3F, 0xD088, 0x75E3, 0xFE54, 0xE93A, 0x628D,
-	0x285B, 0xA3EC, 0xB482, 0x3F35, 0x9A5E, 0x11E9, 0x0687, 0x8D30,
-	0xE232, 0x6985, 0x7EEB, 0xF55C, 0x5037, 0xDB80, 0xCCEE, 0x4759,
-	0x0D8F, 0x8638, 0x9156, 0x1AE1, 0xBF8A, 0x343D, 0x2353, 0xA8E4,
-	0xB6FF, 0x3D48, 0x2A26, 0xA191, 0x04FA, 0x8F4D, 0x9823, 0x1394,
-	0x5942, 0xD2F5, 0xC59B, 0x4E2C, 0xEB47, 0x60F0, 0x779E, 0xFC29,
-	0x4BA8, 0xC01F, 0xD771, 0x5CC6, 0xF9AD, 0x721A, 0x6574, 0xEEC3,
-	0xA415, 0x2FA2, 0x38CC, 0xB37B, 0x1610, 0x9DA7, 0x8AC9, 0x017E,
-	0x1F65, 0x94D2, 0x83BC, 0x080B, 0xAD60, 0x26D7, 0x31B9, 0xBA0E,
-	0xF0D8, 0x7B6F, 0x6C01, 0xE7B6, 0x42DD, 0xC96A, 0xDE04, 0x55B3
-};
+static struct crypto_shash *crct10dif_tfm;
 
 __u16 crc_t10dif(const unsigned char *buffer, size_t len)
 {
-	__u16 crc = 0;
-	unsigned int i;
+	struct {
+		struct shash_desc shash;
+		char ctx[2];
+	} desc;
+	int err;
 
-	for (i = 0 ; i < len ; i++)
-		crc = (crc << 8) ^ t10_dif_crc_table[((crc >> 8) ^ buffer[i]) & 0xff];
+	desc.shash.tfm = crct10dif_tfm;
+	desc.shash.flags = 0;
+	*(__u16 *)desc.ctx = 0;
 
-	return crc;
+	err = crypto_shash_update(&desc.shash, buffer, len);
+	BUG_ON(err);
+
+	return *(__u16 *)desc.ctx;
 }
 EXPORT_SYMBOL(crc_t10dif);
 
+static int __init crc_t10dif_mod_init(void)
+{
+	crct10dif_tfm = crypto_alloc_shash("crct10dif", 0, 0);
+	return PTR_RET(crct10dif_tfm);
+}
+
+static void __exit crc_t10dif_mod_fini(void)
+{
+	crypto_free_shash(crct10dif_tfm);
+}
+
+module_init(crc_t10dif_mod_init);
+module_exit(crc_t10dif_mod_fini);
+
 MODULE_DESCRIPTION("T10 DIF CRC calculation");
 MODULE_LICENSE("GPL");
+MODULE_SOFTDEP("pre: crct10dif");