lib/crypto: arm64/sha512: Remove obsolete chunking logic

Since commit aefbab8e77eb ("arm64: fpsimd: Preserve/restore kernel mode
NEON at context switch"), kernel-mode NEON sections have been
preemptible on arm64.  And since commit 7dadeaa6e851 ("sched: Further
restrict the preemption modes"), voluntary preemption is no longer
supported on arm64 either.  Therefore, there's no longer any need to
limit the length of kernel-mode NEON sections on arm64.

Simplify the SHA-512 code accordingly.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20260401000548.133151-8-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>

diff --git a/lib/crypto/arm64/sha512-ce-core.S b/lib/crypto/arm64/sha512-ce-core.S
index ffd51acfd1eed02cb085edbda19f451a9deb2415..26834921e8d6f8801a11df6ad73ff65a2bdd350c 100644 (file)
--- a/lib/crypto/arm64/sha512-ce-core.S
+++ b/lib/crypto/arm64/sha512-ce-core.S
@@ -93,11 +93,11 @@
        .endm
 
        /*
-        * size_t __sha512_ce_transform(struct sha512_block_state *state,
-        *                              const u8 *data, size_t nblocks);
+        * void sha512_ce_transform(struct sha512_block_state *state,
+        *                          const u8 *data, size_t nblocks);
         */
        .text
-SYM_FUNC_START(__sha512_ce_transform)
+SYM_FUNC_START(sha512_ce_transform)
        /* load state */
        ld1             {v8.2d-v11.2d}, [x0]
 
@@ -186,12 +186,10 @@ CPU_LE(   rev64           v19.16b, v19.16b        )
        add             v10.2d, v10.2d, v2.2d
        add             v11.2d, v11.2d, v3.2d
 
-       cond_yield      3f, x4, x5
        /* handled all input blocks? */
        cbnz            x2, 0b
 
        /* store new state */
-3:     st1             {v8.2d-v11.2d}, [x0]
-       mov             x0, x2
+       st1             {v8.2d-v11.2d}, [x0]
        ret
-SYM_FUNC_END(__sha512_ce_transform)
+SYM_FUNC_END(sha512_ce_transform)

diff --git a/lib/crypto/arm64/sha512.h b/lib/crypto/arm64/sha512.h
index d978c4d07e905388fbf5dbb866cb0e77fd1317cd..5da27e6e23ea2c90765bc13674b918833d052183 100644 (file)
--- a/lib/crypto/arm64/sha512.h
+++ b/lib/crypto/arm64/sha512.h
@@ -12,23 +12,16 @@ static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_sha512_insns);
 
 asmlinkage void sha512_block_data_order(struct sha512_block_state *state,
                                        const u8 *data, size_t nblocks);
-asmlinkage size_t __sha512_ce_transform(struct sha512_block_state *state,
-                                       const u8 *data, size_t nblocks);
+asmlinkage void sha512_ce_transform(struct sha512_block_state *state,
+                                   const u8 *data, size_t nblocks);
 
 static void sha512_blocks(struct sha512_block_state *state,
                          const u8 *data, size_t nblocks)
 {
        if (static_branch_likely(&have_sha512_insns) &&
            likely(may_use_simd())) {
-               do {
-                       size_t rem;
-
-                       scoped_ksimd()
-                               rem = __sha512_ce_transform(state, data, nblocks);
-
-                       data += (nblocks - rem) * SHA512_BLOCK_SIZE;
-                       nblocks = rem;
-               } while (nblocks);
+               scoped_ksimd()
+                       sha512_ce_transform(state, data, nblocks);
        } else {
                sha512_block_data_order(state, data, nblocks);
        }