sparc/crc32: expose CRC32 functions through lib

Move the sparc CRC32C assembly code into the lib directory and wire it
up to the library interface.  This allows it to be used without going
through the crypto API.  It remains usable via the crypto API too via
the shash algorithms that use the library interface.  Thus all the
arch-specific "shash" code becomes unnecessary and is removed.

Note: to see the diff from arch/sparc/crypto/crc32c_glue.c to
arch/sparc/lib/crc32_glue.c, view this commit with 'git show -M10'.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20241202010844.144356-11-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>

7 files changed, 97 insertions, 199 deletions

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index dcfdb7f1dae9..0f88123925a4 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -110,6 +110,7 @@ config SPARC64
 	select HAVE_SETUP_PER_CPU_AREA
 	select NEED_PER_CPU_EMBED_FIRST_CHUNK
 	select NEED_PER_CPU_PAGE_FIRST_CHUNK
+	select ARCH_HAS_CRC32
 
 config ARCH_PROC_KCORE_TEXT
 	def_bool y
diff --git a/arch/sparc/crypto/Kconfig b/arch/sparc/crypto/Kconfig
index cfe5102b1c68..e858597de89d 100644
--- a/arch/sparc/crypto/Kconfig
+++ b/arch/sparc/crypto/Kconfig
@@ -16,16 +16,6 @@ config CRYPTO_DES_SPARC64
 
 	  Architecture: sparc64
 
-config CRYPTO_CRC32C_SPARC64
-	tristate "CRC32c"
-	depends on SPARC64
-	select CRYPTO_HASH
-	select CRC32
-	help
-	  CRC32c CRC algorithm with the iSCSI polynomial (RFC 3385 and RFC 3720)
-
-	  Architecture: sparc64
-
 config CRYPTO_MD5_SPARC64
 	tristate "Digests: MD5"
 	depends on SPARC64
diff --git a/arch/sparc/crypto/Makefile b/arch/sparc/crypto/Makefile
index d257186c27d1..a2d7fca40cb4 100644
--- a/arch/sparc/crypto/Makefile
+++ b/arch/sparc/crypto/Makefile
@@ -12,8 +12,6 @@ obj-$(CONFIG_CRYPTO_AES_SPARC64) += aes-sparc64.o
 obj-$(CONFIG_CRYPTO_DES_SPARC64) += des-sparc64.o
 obj-$(CONFIG_CRYPTO_CAMELLIA_SPARC64) += camellia-sparc64.o
 
-obj-$(CONFIG_CRYPTO_CRC32C_SPARC64) += crc32c-sparc64.o
-
 sha1-sparc64-y := sha1_asm.o sha1_glue.o
 sha256-sparc64-y := sha256_asm.o sha256_glue.o
 sha512-sparc64-y := sha512_asm.o sha512_glue.o
@@ -22,5 +20,3 @@ md5-sparc64-y := md5_asm.o md5_glue.o
 aes-sparc64-y := aes_asm.o aes_glue.o
 des-sparc64-y := des_asm.o des_glue.o
 camellia-sparc64-y := camellia_asm.o camellia_glue.o
-
-crc32c-sparc64-y := crc32c_asm.o crc32c_glue.o
diff --git a/arch/sparc/crypto/crc32c_glue.c b/arch/sparc/crypto/crc32c_glue.c
deleted file mode 100644
index 913b9a09e885..000000000000
--- a/arch/sparc/crypto/crc32c_glue.c
+++ /dev/null
@@ -1,184 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/* Glue code for CRC32C optimized for sparc64 crypto opcodes.
- *
- * This is based largely upon arch/x86/crypto/crc32c-intel.c
- *
- * Copyright (C) 2008 Intel Corporation
- * Authors: Austin Zhang <austin_zhang@linux.intel.com>
- *          Kent Liu <kent.liu@intel.com>
- */
-
-#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
-
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/string.h>
-#include <linux/kernel.h>
-#include <linux/crc32.h>
-
-#include <crypto/internal/hash.h>
-
-#include <asm/pstate.h>
-#include <asm/elf.h>
-#include <linux/unaligned.h>
-
-#include "opcodes.h"
-
-/*
- * Setting the seed allows arbitrary accumulators and flexible XOR policy
- * If your algorithm starts with ~0, then XOR with ~0 before you set
- * the seed.
- */
-static int crc32c_sparc64_setkey(struct crypto_shash *hash, const u8 *key,
-				 unsigned int keylen)
-{
-	u32 *mctx = crypto_shash_ctx(hash);
-
-	if (keylen != sizeof(u32))
-		return -EINVAL;
-	*mctx = get_unaligned_le32(key);
-	return 0;
-}
-
-static int crc32c_sparc64_init(struct shash_desc *desc)
-{
-	u32 *mctx = crypto_shash_ctx(desc->tfm);
-	u32 *crcp = shash_desc_ctx(desc);
-
-	*crcp = *mctx;
-
-	return 0;
-}
-
-extern void crc32c_sparc64(u32 *crcp, const u64 *data, unsigned int len);
-
-static u32 crc32c_compute(u32 crc, const u8 *data, unsigned int len)
-{
-	unsigned int n = -(uintptr_t)data & 7;
-
-	if (n) {
-		/* Data isn't 8-byte aligned.  Align it. */
-		n = min(n, len);
-		crc = __crc32c_le(crc, data, n);
-		data += n;
-		len -= n;
-	}
-	n = len & ~7U;
-	if (n) {
-		crc32c_sparc64(&crc, (const u64 *)data, n);
-		data += n;
-		len -= n;
-	}
-	if (len)
-		crc = __crc32c_le(crc, data, len);
-	return crc;
-}
-
-static int crc32c_sparc64_update(struct shash_desc *desc, const u8 *data,
-				 unsigned int len)
-{
-	u32 *crcp = shash_desc_ctx(desc);
-
-	*crcp = crc32c_compute(*crcp, data, len);
-	return 0;
-}
-
-static int __crc32c_sparc64_finup(const u32 *crcp, const u8 *data,
-				  unsigned int len, u8 *out)
-{
-	put_unaligned_le32(~crc32c_compute(*crcp, data, len), out);
-	return 0;
-}
-
-static int crc32c_sparc64_finup(struct shash_desc *desc, const u8 *data,
-				unsigned int len, u8 *out)
-{
-	return __crc32c_sparc64_finup(shash_desc_ctx(desc), data, len, out);
-}
-
-static int crc32c_sparc64_final(struct shash_desc *desc, u8 *out)
-{
-	u32 *crcp = shash_desc_ctx(desc);
-
-	put_unaligned_le32(~*crcp, out);
-	return 0;
-}
-
-static int crc32c_sparc64_digest(struct shash_desc *desc, const u8 *data,
-				 unsigned int len, u8 *out)
-{
-	return __crc32c_sparc64_finup(crypto_shash_ctx(desc->tfm), data, len,
-				      out);
-}
-
-static int crc32c_sparc64_cra_init(struct crypto_tfm *tfm)
-{
-	u32 *key = crypto_tfm_ctx(tfm);
-
-	*key = ~0;
-
-	return 0;
-}
-
-#define CHKSUM_BLOCK_SIZE	1
-#define CHKSUM_DIGEST_SIZE	4
-
-static struct shash_alg alg = {
-	.setkey			=	crc32c_sparc64_setkey,
-	.init			=	crc32c_sparc64_init,
-	.update			=	crc32c_sparc64_update,
-	.final			=	crc32c_sparc64_final,
-	.finup			=	crc32c_sparc64_finup,
-	.digest			=	crc32c_sparc64_digest,
-	.descsize		=	sizeof(u32),
-	.digestsize		=	CHKSUM_DIGEST_SIZE,
-	.base			=	{
-		.cra_name		=	"crc32c",
-		.cra_driver_name	=	"crc32c-sparc64",
-		.cra_priority		=	SPARC_CR_OPCODE_PRIORITY,
-		.cra_flags		=	CRYPTO_ALG_OPTIONAL_KEY,
-		.cra_blocksize		=	CHKSUM_BLOCK_SIZE,
-		.cra_ctxsize		=	sizeof(u32),
-		.cra_module		=	THIS_MODULE,
-		.cra_init		=	crc32c_sparc64_cra_init,
-	}
-};
-
-static bool __init sparc64_has_crc32c_opcode(void)
-{
-	unsigned long cfr;
-
-	if (!(sparc64_elf_hwcap & HWCAP_SPARC_CRYPTO))
-		return false;
-
-	__asm__ __volatile__("rd %%asr26, %0" : "=r" (cfr));
-	if (!(cfr & CFR_CRC32C))
-		return false;
-
-	return true;
-}
-
-static int __init crc32c_sparc64_mod_init(void)
-{
-	if (sparc64_has_crc32c_opcode()) {
-		pr_info("Using sparc64 crc32c opcode optimized CRC32C implementation\n");
-		return crypto_register_shash(&alg);
-	}
-	pr_info("sparc64 crc32c opcode not available.\n");
-	return -ENODEV;
-}
-
-static void __exit crc32c_sparc64_mod_fini(void)
-{
-	crypto_unregister_shash(&alg);
-}
-
-module_init(crc32c_sparc64_mod_init);
-module_exit(crc32c_sparc64_mod_fini);
-
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("CRC32c (Castagnoli), sparc64 crc32c opcode accelerated");
-
-MODULE_ALIAS_CRYPTO("crc32c");
-
-#include "crop_devid.c"
diff --git a/arch/sparc/lib/Makefile b/arch/sparc/lib/Makefile
index ee5091dd67ed..5724d0f356eb 100644
--- a/arch/sparc/lib/Makefile
+++ b/arch/sparc/lib/Makefile
@@ -53,3 +53,5 @@ lib-$(CONFIG_SPARC64) += mcount.o ipcsum.o xor.o hweight.o ffs.o
 obj-$(CONFIG_SPARC64) += iomap.o
 obj-$(CONFIG_SPARC32) += atomic32.o
 obj-$(CONFIG_SPARC64) += PeeCeeI.o
+obj-$(CONFIG_CRC32_ARCH) += crc32-sparc.o
+crc32-sparc-y := crc32_glue.o crc32c_asm.o
diff --git a/arch/sparc/lib/crc32_glue.c b/arch/sparc/lib/crc32_glue.c
new file mode 100644
index 000000000000..41076d2b1fd2
--- /dev/null
+++ b/arch/sparc/lib/crc32_glue.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Glue code for CRC32C optimized for sparc64 crypto opcodes.
+ *
+ * This is based largely upon arch/x86/crypto/crc32c-intel.c
+ *
+ * Copyright (C) 2008 Intel Corporation
+ * Authors: Austin Zhang <austin_zhang@linux.intel.com>
+ *          Kent Liu <kent.liu@intel.com>
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/crc32.h>
+#include <asm/pstate.h>
+#include <asm/elf.h>
+
+static DEFINE_STATIC_KEY_FALSE(have_crc32c_opcode);
+
+u32 crc32_le_arch(u32 crc, const u8 *data, size_t len)
+{
+	return crc32_le_base(crc, data, len);
+}
+EXPORT_SYMBOL(crc32_le_arch);
+
+void crc32c_sparc64(u32 *crcp, const u64 *data, size_t len);
+
+u32 crc32c_le_arch(u32 crc, const u8 *data, size_t len)
+{
+	size_t n = -(uintptr_t)data & 7;
+
+	if (!static_branch_likely(&have_crc32c_opcode))
+		return crc32c_le_base(crc, data, len);
+
+	if (n) {
+		/* Data isn't 8-byte aligned.  Align it. */
+		n = min(n, len);
+		crc = crc32c_le_base(crc, data, n);
+		data += n;
+		len -= n;
+	}
+	n = len & ~7U;
+	if (n) {
+		crc32c_sparc64(&crc, (const u64 *)data, n);
+		data += n;
+		len -= n;
+	}
+	if (len)
+		crc = crc32c_le_base(crc, data, len);
+	return crc;
+}
+EXPORT_SYMBOL(crc32c_le_arch);
+
+u32 crc32_be_arch(u32 crc, const u8 *data, size_t len)
+{
+	return crc32_be_base(crc, data, len);
+}
+EXPORT_SYMBOL(crc32_be_arch);
+
+static int __init crc32_sparc_init(void)
+{
+	unsigned long cfr;
+
+	if (!(sparc64_elf_hwcap & HWCAP_SPARC_CRYPTO))
+		return 0;
+
+	__asm__ __volatile__("rd %%asr26, %0" : "=r" (cfr));
+	if (!(cfr & CFR_CRC32C))
+		return 0;
+
+	static_branch_enable(&have_crc32c_opcode);
+	pr_info("Using sparc64 crc32c opcode optimized CRC32C implementation\n");
+	return 0;
+}
+arch_initcall(crc32_sparc_init);
+
+static void __exit crc32_sparc_exit(void)
+{
+}
+module_exit(crc32_sparc_exit);
+
+u32 crc32_optimizations(void)
+{
+	if (static_key_enabled(&have_crc32c_opcode))
+		return CRC32C_OPTIMIZATION;
+	return 0;
+}
+EXPORT_SYMBOL(crc32_optimizations);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("CRC32c (Castagnoli), sparc64 crc32c opcode accelerated");
diff --git a/arch/sparc/crypto/crc32c_asm.S b/arch/sparc/lib/crc32c_asm.S
index b8659a479242..ee454fa6aed6 100644
--- a/arch/sparc/crypto/crc32c_asm.S
+++ b/arch/sparc/lib/crc32c_asm.S
@@ -3,7 +3,7 @@
 #include <asm/visasm.h>
 #include <asm/asi.h>
 
-#include "opcodes.h"
+#include "../crypto/opcodes.h"
 
 ENTRY(crc32c_sparc64)
 	/* %o0=crc32p, %o1=data_ptr, %o2=len */