[PATCH v2 09/19] crypto: x86 - use common macro for FPU limit

[Robert Elliott <elliott@hpe.com>]

Use a common macro name (FPU_BYTES) for the limit of the number of bytes
processed within kernel_fpu_begin and kernel_fpu_end rather than
using SZ_4K (which is a signed value), or a magic value of 4096U.

Use unsigned int rather than size_t for some of the arguments to
avoid typecasting for the min() macro.

Signed-off-by: Robert Elliott <elliott@hpe.com>
---
 arch/x86/crypto/blake2s-glue.c         |  7 ++++---
 arch/x86/crypto/chacha_glue.c          |  4 +++-
 arch/x86/crypto/nhpoly1305-avx2-glue.c |  4 +++-
 arch/x86/crypto/nhpoly1305-sse2-glue.c |  4 +++-
 arch/x86/crypto/poly1305_glue.c        | 25 ++++++++++++++-----------
 arch/x86/crypto/polyval-clmulni_glue.c |  5 +++--
 6 files changed, 30 insertions(+), 19 deletions(-)

diff --git a/arch/x86/crypto/blake2s-glue.c b/arch/x86/crypto/blake2s-glue.c
index aaba21230528..3054ee7fa219 100644
--- a/arch/x86/crypto/blake2s-glue.c
+++ b/arch/x86/crypto/blake2s-glue.c
@@ -16,6 +16,8 @@
 #include <asm/processor.h>
 #include <asm/simd.h>
 
+#define FPU_BYTES 4096U /* avoid kernel_fpu_begin/end scheduler/rcu stalls */
+
 asmlinkage void blake2s_compress_ssse3(struct blake2s_state *state,
 				       const u8 *block, const size_t nblocks,
 				       const u32 inc);
@@ -29,8 +31,7 @@ static __ro_after_init DEFINE_STATIC_KEY_FALSE(blake2s_use_avx512);
 void blake2s_compress(struct blake2s_state *state, const u8 *block,
 		      size_t nblocks, const u32 inc)
 {
-	/* SIMD disables preemption, so relax after processing each page. */
-	BUILD_BUG_ON(SZ_4K / BLAKE2S_BLOCK_SIZE < 8);
+	BUILD_BUG_ON(FPU_BYTES / BLAKE2S_BLOCK_SIZE < 8);
 
 	if (!static_branch_likely(&blake2s_use_ssse3) || !may_use_simd()) {
 		blake2s_compress_generic(state, block, nblocks, inc);
@@ -39,7 +40,7 @@ void blake2s_compress(struct blake2s_state *state, const u8 *block,
 
 	do {
 		const size_t blocks = min_t(size_t, nblocks,
-					    SZ_4K / BLAKE2S_BLOCK_SIZE);
+					    FPU_BYTES / BLAKE2S_BLOCK_SIZE);
 
 		kernel_fpu_begin();
 		if (IS_ENABLED(CONFIG_AS_AVX512) &&
diff --git a/arch/x86/crypto/chacha_glue.c b/arch/x86/crypto/chacha_glue.c
index 7b3a1cf0984b..0d7e172862db 100644
--- a/arch/x86/crypto/chacha_glue.c
+++ b/arch/x86/crypto/chacha_glue.c
@@ -15,6 +15,8 @@
 #include <linux/sizes.h>
 #include <asm/simd.h>
 
+#define FPU_BYTES 4096U /* avoid kernel_fpu_begin/end scheduler/rcu stalls */
+
 asmlinkage void chacha_block_xor_ssse3(u32 *state, u8 *dst, const u8 *src,
 				       unsigned int len, int nrounds);
 asmlinkage void chacha_4block_xor_ssse3(u32 *state, u8 *dst, const u8 *src,
@@ -147,7 +149,7 @@ void chacha_crypt_arch(u32 *state, u8 *dst, const u8 *src, unsigned int bytes,
 		return chacha_crypt_generic(state, dst, src, bytes, nrounds);
 
 	do {
-		unsigned int todo = min_t(unsigned int, bytes, SZ_4K);
+		unsigned int todo = min(bytes, FPU_BYTES);
 
 		kernel_fpu_begin();
 		chacha_dosimd(state, dst, src, todo, nrounds);
diff --git a/arch/x86/crypto/nhpoly1305-avx2-glue.c b/arch/x86/crypto/nhpoly1305-avx2-glue.c
index 8ea5ab0f1ca7..59615ae95e86 100644
--- a/arch/x86/crypto/nhpoly1305-avx2-glue.c
+++ b/arch/x86/crypto/nhpoly1305-avx2-glue.c
@@ -13,6 +13,8 @@
 #include <linux/sizes.h>
 #include <asm/simd.h>
 
+#define FPU_BYTES 4096U /* avoid kernel_fpu_begin/end scheduler/rcu stalls */
+
 asmlinkage void nh_avx2(const u32 *key, const u8 *message, size_t message_len,
 			u8 hash[NH_HASH_BYTES]);
 
@@ -30,7 +32,7 @@ static int nhpoly1305_avx2_update(struct shash_desc *desc,
 		return crypto_nhpoly1305_update(desc, src, srclen);
 
 	do {
-		unsigned int n = min_t(unsigned int, srclen, SZ_4K);
+		unsigned int n = min(srclen, FPU_BYTES);
 
 		kernel_fpu_begin();
 		crypto_nhpoly1305_update_helper(desc, src, n, _nh_avx2);
diff --git a/arch/x86/crypto/nhpoly1305-sse2-glue.c b/arch/x86/crypto/nhpoly1305-sse2-glue.c
index 2b353d42ed13..bf91c375821a 100644
--- a/arch/x86/crypto/nhpoly1305-sse2-glue.c
+++ b/arch/x86/crypto/nhpoly1305-sse2-glue.c
@@ -13,6 +13,8 @@
 #include <linux/sizes.h>
 #include <asm/simd.h>
 
+#define FPU_BYTES 4096U /* avoid kernel_fpu_begin/end scheduler/rcu stalls */
+
 asmlinkage void nh_sse2(const u32 *key, const u8 *message, size_t message_len,
 			u8 hash[NH_HASH_BYTES]);
 
@@ -30,7 +32,7 @@ static int nhpoly1305_sse2_update(struct shash_desc *desc,
 		return crypto_nhpoly1305_update(desc, src, srclen);
 
 	do {
-		unsigned int n = min_t(unsigned int, srclen, SZ_4K);
+		unsigned int n = min(srclen, FPU_BYTES);
 
 		kernel_fpu_begin();
 		crypto_nhpoly1305_update_helper(desc, src, n, _nh_sse2);
diff --git a/arch/x86/crypto/poly1305_glue.c b/arch/x86/crypto/poly1305_glue.c
index 1dfb8af48a3c..3764301bdf1b 100644
--- a/arch/x86/crypto/poly1305_glue.c
+++ b/arch/x86/crypto/poly1305_glue.c
@@ -15,20 +15,24 @@
 #include <asm/intel-family.h>
 #include <asm/simd.h>
 
+#define FPU_BYTES 4096U /* avoid kernel_fpu_begin/end scheduler/rcu stalls */
+
 asmlinkage void poly1305_init_x86_64(void *ctx,
 				     const u8 key[POLY1305_BLOCK_SIZE]);
 asmlinkage void poly1305_blocks_x86_64(void *ctx, const u8 *inp,
-				       const size_t len, const u32 padbit);
+				       const unsigned int len,
+				       const u32 padbit);
 asmlinkage void poly1305_emit_x86_64(void *ctx, u8 mac[POLY1305_DIGEST_SIZE],
 				     const u32 nonce[4]);
 asmlinkage void poly1305_emit_avx(void *ctx, u8 mac[POLY1305_DIGEST_SIZE],
 				  const u32 nonce[4]);
-asmlinkage void poly1305_blocks_avx(void *ctx, const u8 *inp, const size_t len,
-				    const u32 padbit);
-asmlinkage void poly1305_blocks_avx2(void *ctx, const u8 *inp, const size_t len,
-				     const u32 padbit);
+asmlinkage void poly1305_blocks_avx(void *ctx, const u8 *inp,
+				    const unsigned int len, const u32 padbit);
+asmlinkage void poly1305_blocks_avx2(void *ctx, const u8 *inp,
+				     const unsigned int len, const u32 padbit);
 asmlinkage void poly1305_blocks_avx512(void *ctx, const u8 *inp,
-				       const size_t len, const u32 padbit);
+				       const unsigned int len,
+				       const u32 padbit);
 
 static __ro_after_init DEFINE_STATIC_KEY_FALSE(poly1305_use_avx);
 static __ro_after_init DEFINE_STATIC_KEY_FALSE(poly1305_use_avx2);
@@ -86,14 +90,13 @@ static void poly1305_simd_init(void *ctx, const u8 key[POLY1305_BLOCK_SIZE])
 	poly1305_init_x86_64(ctx, key);
 }
 
-static void poly1305_simd_blocks(void *ctx, const u8 *inp, size_t len,
+static void poly1305_simd_blocks(void *ctx, const u8 *inp, unsigned int len,
 				 const u32 padbit)
 {
 	struct poly1305_arch_internal *state = ctx;
 
-	/* SIMD disables preemption, so relax after processing each page. */
-	BUILD_BUG_ON(SZ_4K < POLY1305_BLOCK_SIZE ||
-		     SZ_4K % POLY1305_BLOCK_SIZE);
+	BUILD_BUG_ON(FPU_BYTES < POLY1305_BLOCK_SIZE ||
+		     FPU_BYTES % POLY1305_BLOCK_SIZE);
 
 	if (!static_branch_likely(&poly1305_use_avx) ||
 	    (len < (POLY1305_BLOCK_SIZE * 18) && !state->is_base2_26) ||
@@ -104,7 +107,7 @@ static void poly1305_simd_blocks(void *ctx, const u8 *inp, size_t len,
 	}
 
 	do {
-		const size_t bytes = min_t(size_t, len, SZ_4K);
+		const unsigned int bytes = min(len, FPU_BYTES);
 
 		kernel_fpu_begin();
 		if (IS_ENABLED(CONFIG_AS_AVX512) && static_branch_likely(&poly1305_use_avx512))
diff --git a/arch/x86/crypto/polyval-clmulni_glue.c b/arch/x86/crypto/polyval-clmulni_glue.c
index b7664d018851..2502964afef6 100644
--- a/arch/x86/crypto/polyval-clmulni_glue.c
+++ b/arch/x86/crypto/polyval-clmulni_glue.c
@@ -29,6 +29,8 @@
 
 #define NUM_KEY_POWERS	8
 
+#define FPU_BYTES 4096U /* avoid kernel_fpu_begin/end scheduler/rcu stalls */
+
 struct polyval_tfm_ctx {
 	/*
 	 * These powers must be in the order h^8, ..., h^1.
@@ -123,8 +125,7 @@ static int polyval_x86_update(struct shash_desc *desc,
 	}
 
 	while (srclen >= POLYVAL_BLOCK_SIZE) {
-		/* Allow rescheduling every 4K bytes. */
-		nblocks = min(srclen, 4096U) / POLYVAL_BLOCK_SIZE;
+		nblocks = min(srclen, FPU_BYTES) / POLYVAL_BLOCK_SIZE;
 		internal_polyval_update(tctx, src, nblocks, dctx->buffer);
 		srclen -= nblocks * POLYVAL_BLOCK_SIZE;
 		src += nblocks * POLYVAL_BLOCK_SIZE;
-- 
2.37.3