Merge tag 'for-5.18/64bit-pi-2022-03-25' of git://git.kernel.dk/linux-block

Pull block layer 64-bit data integrity support from Jens Axboe:
 "This adds support for 64-bit data integrity in the block layer and in
  NVMe"

* tag 'for-5.18/64bit-pi-2022-03-25' of git://git.kernel.dk/linux-block:
  crypto: fix crc64 testmgr digest byte order
  nvme: add support for enhanced metadata
  block: add pi for extended integrity
  crypto: add rocksoft 64b crc guard tag framework
  lib: add rocksoft model crc64
  linux/kernel: introduce lower_48_bits function
  asm-generic: introduce be48 unaligned accessors
  nvme: allow integrity on extended metadata formats
  block: support pi with extended metadata

5 files changed, 204 insertions, 11 deletions

diff --git a/lib/Kconfig b/lib/Kconfig
index 9b5a692ce00c..087e06b4cdfd 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -145,6 +145,15 @@ config CRC_T10DIF
 	  kernel tree needs to calculate CRC checks for use with the
 	  SCSI data integrity subsystem.
 
+config CRC64_ROCKSOFT
+	tristate "CRC calculation for the Rocksoft model CRC64"
+	select CRC64
+	select CRYPTO
+	select CRYPTO_CRC64_ROCKSOFT
+	help
+	  This option provides a CRC64 API to a registered crypto driver.
+	  This is used with the block layer's data integrity subsystem.
+
 config CRC_ITU_T
 	tristate "CRC ITU-T V.41 functions"
 	help
diff --git a/lib/Makefile b/lib/Makefile
index 2fd40c5bf378..df001b876930 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -174,6 +174,7 @@ obj-$(CONFIG_CRC4)	+= crc4.o
 obj-$(CONFIG_CRC7)	+= crc7.o
 obj-$(CONFIG_LIBCRC32C)	+= libcrc32c.o
 obj-$(CONFIG_CRC8)	+= crc8.o
+obj-$(CONFIG_CRC64_ROCKSOFT) += crc64-rocksoft.o
 obj-$(CONFIG_XXHASH)	+= xxhash.o
 obj-$(CONFIG_GENERIC_ALLOCATOR) += genalloc.o
 
diff --git a/lib/crc64-rocksoft.c b/lib/crc64-rocksoft.c
new file mode 100644
index 000000000000..fc9ae0da5df7
--- /dev/null
+++ b/lib/crc64-rocksoft.c
@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/crc64.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <crypto/hash.h>
+#include <crypto/algapi.h>
+#include <linux/static_key.h>
+#include <linux/notifier.h>
+
+static struct crypto_shash __rcu *crc64_rocksoft_tfm;
+static DEFINE_STATIC_KEY_TRUE(crc64_rocksoft_fallback);
+static DEFINE_MUTEX(crc64_rocksoft_mutex);
+static struct work_struct crc64_rocksoft_rehash_work;
+
+static int crc64_rocksoft_notify(struct notifier_block *self, unsigned long val, void *data)
+{
+	struct crypto_alg *alg = data;
+
+	if (val != CRYPTO_MSG_ALG_LOADED ||
+	    strcmp(alg->cra_name, CRC64_ROCKSOFT_STRING))
+		return NOTIFY_DONE;
+
+	schedule_work(&crc64_rocksoft_rehash_work);
+	return NOTIFY_OK;
+}
+
+static void crc64_rocksoft_rehash(struct work_struct *work)
+{
+	struct crypto_shash *new, *old;
+
+	mutex_lock(&crc64_rocksoft_mutex);
+	old = rcu_dereference_protected(crc64_rocksoft_tfm,
+					lockdep_is_held(&crc64_rocksoft_mutex));
+	new = crypto_alloc_shash(CRC64_ROCKSOFT_STRING, 0, 0);
+	if (IS_ERR(new)) {
+		mutex_unlock(&crc64_rocksoft_mutex);
+		return;
+	}
+	rcu_assign_pointer(crc64_rocksoft_tfm, new);
+	mutex_unlock(&crc64_rocksoft_mutex);
+
+	if (old) {
+		synchronize_rcu();
+		crypto_free_shash(old);
+	} else {
+		static_branch_disable(&crc64_rocksoft_fallback);
+	}
+}
+
+static struct notifier_block crc64_rocksoft_nb = {
+	.notifier_call = crc64_rocksoft_notify,
+};
+
+u64 crc64_rocksoft_update(u64 crc, const unsigned char *buffer, size_t len)
+{
+	struct {
+		struct shash_desc shash;
+		u64 crc;
+	} desc;
+	int err;
+
+	if (static_branch_unlikely(&crc64_rocksoft_fallback))
+		return crc64_rocksoft_generic(crc, buffer, len);
+
+	rcu_read_lock();
+	desc.shash.tfm = rcu_dereference(crc64_rocksoft_tfm);
+	desc.crc = crc;
+	err = crypto_shash_update(&desc.shash, buffer, len);
+	rcu_read_unlock();
+
+	BUG_ON(err);
+
+	return desc.crc;
+}
+EXPORT_SYMBOL_GPL(crc64_rocksoft_update);
+
+u64 crc64_rocksoft(const unsigned char *buffer, size_t len)
+{
+	return crc64_rocksoft_update(0, buffer, len);
+}
+EXPORT_SYMBOL_GPL(crc64_rocksoft);
+
+static int __init crc64_rocksoft_mod_init(void)
+{
+	INIT_WORK(&crc64_rocksoft_rehash_work, crc64_rocksoft_rehash);
+	crypto_register_notifier(&crc64_rocksoft_nb);
+	crc64_rocksoft_rehash(&crc64_rocksoft_rehash_work);
+	return 0;
+}
+
+static void __exit crc64_rocksoft_mod_fini(void)
+{
+	crypto_unregister_notifier(&crc64_rocksoft_nb);
+	cancel_work_sync(&crc64_rocksoft_rehash_work);
+	crypto_free_shash(rcu_dereference_protected(crc64_rocksoft_tfm, 1));
+}
+
+module_init(crc64_rocksoft_mod_init);
+module_exit(crc64_rocksoft_mod_fini);
+
+static int crc64_rocksoft_transform_show(char *buffer, const struct kernel_param *kp)
+{
+	struct crypto_shash *tfm;
+	int len;
+
+	if (static_branch_unlikely(&crc64_rocksoft_fallback))
+		return sprintf(buffer, "fallback\n");
+
+	rcu_read_lock();
+	tfm = rcu_dereference(crc64_rocksoft_tfm);
+	len = snprintf(buffer, PAGE_SIZE, "%s\n",
+		       crypto_shash_driver_name(tfm));
+	rcu_read_unlock();
+
+	return len;
+}
+
+module_param_call(transform, NULL, crc64_rocksoft_transform_show, NULL, 0444);
+
+MODULE_AUTHOR("Keith Busch <kbusch@kernel.org>");
+MODULE_DESCRIPTION("Rocksoft model CRC64 calculation (library API)");
+MODULE_LICENSE("GPL");
+MODULE_SOFTDEP("pre: crc64");
diff --git a/lib/crc64.c b/lib/crc64.c
index 9f852a89ee2a..61ae8dfb6a1c 100644
--- a/lib/crc64.c
+++ b/lib/crc64.c
@@ -22,6 +22,13 @@
  * x^24 + x^23 + x^22 + x^21 + x^19 + x^17 + x^13 + x^12 + x^10 + x^9 +
  * x^7 + x^4 + x + 1
  *
+ * crc64rocksoft[256] table is from the Rocksoft specification polynomial
+ * defined as,
+ *
+ * x^64 + x^63 + x^61 + x^59 + x^58 + x^56 + x^55 + x^52 + x^49 + x^48 + x^47 +
+ * x^46 + x^44 + x^41 + x^37 + x^36 + x^34 + x^32 + x^31 + x^28 + x^26 + x^23 +
+ * x^22 + x^19 + x^16 + x^13 + x^12 + x^10 + x^9 + x^6 + x^4 + x^3 + 1
+ *
  * Copyright 2018 SUSE Linux.
  *   Author: Coly Li <colyli@suse.de>
  */
@@ -55,3 +62,24 @@ u64 __pure crc64_be(u64 crc, const void *p, size_t len)
 	return crc;
 }
 EXPORT_SYMBOL_GPL(crc64_be);
+
+/**
+ * crc64_rocksoft_generic - Calculate bitwise Rocksoft CRC64
+ * @crc: seed value for computation. 0 for a new CRC calculation, or the
+ * 	 previous crc64 value if computing incrementally.
+ * @p: pointer to buffer over which CRC64 is run
+ * @len: length of buffer @p
+ */
+u64 __pure crc64_rocksoft_generic(u64 crc, const void *p, size_t len)
+{
+	const unsigned char *_p = p;
+	size_t i;
+
+	crc = ~crc;
+
+	for (i = 0; i < len; i++)
+		crc = (crc >> 8) ^ crc64rocksofttable[(crc & 0xff) ^ *_p++];
+
+	return ~crc;
+}
+EXPORT_SYMBOL_GPL(crc64_rocksoft_generic);
diff --git a/lib/gen_crc64table.c b/lib/gen_crc64table.c
index 094b43aef8db..55e222acd0b8 100644
--- a/lib/gen_crc64table.c
+++ b/lib/gen_crc64table.c
@@ -17,10 +17,30 @@
 #include <stdio.h>
 
 #define CRC64_ECMA182_POLY 0x42F0E1EBA9EA3693ULL
+#define CRC64_ROCKSOFT_POLY 0x9A6C9329AC4BC9B5ULL
 
 static uint64_t crc64_table[256] = {0};
+static uint64_t crc64_rocksoft_table[256] = {0};
 
-static void generate_crc64_table(void)
+static void generate_reflected_crc64_table(uint64_t table[256], uint64_t poly)
+{
+	uint64_t i, j, c, crc;
+
+	for (i = 0; i < 256; i++) {
+		crc = 0ULL;
+		c = i;
+
+		for (j = 0; j < 8; j++) {
+			if ((crc ^ (c >> j)) & 1)
+				crc = (crc >> 1) ^ poly;
+			else
+				crc >>= 1;
+		}
+		table[i] = crc;
+	}
+}
+
+static void generate_crc64_table(uint64_t table[256], uint64_t poly)
 {
 	uint64_t i, j, c, crc;
 
@@ -30,26 +50,22 @@ static void generate_crc64_table(void)
 
 		for (j = 0; j < 8; j++) {
 			if ((crc ^ c) & 0x8000000000000000ULL)
-				crc = (crc << 1) ^ CRC64_ECMA182_POLY;
+				crc = (crc << 1) ^ poly;
 			else
 				crc <<= 1;
 			c <<= 1;
 		}
 
-		crc64_table[i] = crc;
+		table[i] = crc;
 	}
 }
 
-static void print_crc64_table(void)
+static void output_table(uint64_t table[256])
 {
 	int i;
 
-	printf("/* this file is generated - do not edit */\n\n");
-	printf("#include <linux/types.h>\n");
-	printf("#include <linux/cache.h>\n\n");
-	printf("static const u64 ____cacheline_aligned crc64table[256] = {\n");
 	for (i = 0; i < 256; i++) {
-		printf("\t0x%016" PRIx64 "ULL", crc64_table[i]);
+		printf("\t0x%016" PRIx64 "ULL", table[i]);
 		if (i & 0x1)
 			printf(",\n");
 		else
@@ -58,9 +74,22 @@ static void print_crc64_table(void)
 	printf("};\n");
 }
 
+static void print_crc64_tables(void)
+{
+	printf("/* this file is generated - do not edit */\n\n");
+	printf("#include <linux/types.h>\n");
+	printf("#include <linux/cache.h>\n\n");
+	printf("static const u64 ____cacheline_aligned crc64table[256] = {\n");
+	output_table(crc64_table);
+
+	printf("\nstatic const u64 ____cacheline_aligned crc64rocksofttable[256] = {\n");
+	output_table(crc64_rocksoft_table);
+}
+
 int main(int argc, char *argv[])
 {
-	generate_crc64_table();
-	print_crc64_table();
+	generate_crc64_table(crc64_table, CRC64_ECMA182_POLY);
+	generate_reflected_crc64_table(crc64_rocksoft_table, CRC64_ROCKSOFT_POLY);
+	print_crc64_tables();
 	return 0;
 }