On Mon, 3 Jun 2024 at 20:39, Eric Biggers <ebiggers@xxxxxxxxxx> wrote: > > From: Eric Biggers <ebiggers@xxxxxxxxxx> > > Add an implementation of finup_mb to sha256-ce, using an interleaving > factor of 2. It interleaves a finup operation for two equal-length > messages that share a common prefix. dm-verity and fs-verity will take > advantage of this for greatly improved performance on capable CPUs. > > On an ARM Cortex-X1, this increases the throughput of SHA-256 hashing > 4096-byte messages by 70%. > > Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx> Reviewed-by: Ard Biesheuvel <ardb@xxxxxxxxxx> > --- > arch/arm64/crypto/sha2-ce-core.S | 281 ++++++++++++++++++++++++++++++- > arch/arm64/crypto/sha2-ce-glue.c | 40 +++++ > 2 files changed, 315 insertions(+), 6 deletions(-) > > diff --git a/arch/arm64/crypto/sha2-ce-core.S b/arch/arm64/crypto/sha2-ce-core.S > index fce84d88ddb2..fb5d5227e585 100644 > --- a/arch/arm64/crypto/sha2-ce-core.S > +++ b/arch/arm64/crypto/sha2-ce-core.S > @@ -68,22 +68,26 @@ > .word 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5 > .word 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3 > .word 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208 > .word 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2 > > + .macro load_round_constants tmp > + adr_l \tmp, .Lsha2_rcon > + ld1 { v0.4s- v3.4s}, [\tmp], #64 > + ld1 { v4.4s- v7.4s}, [\tmp], #64 > + ld1 { v8.4s-v11.4s}, [\tmp], #64 > + ld1 {v12.4s-v15.4s}, [\tmp] > + .endm > + > /* > * int __sha256_ce_transform(struct sha256_ce_state *sst, u8 const *src, > * int blocks) > */ > .text > SYM_FUNC_START(__sha256_ce_transform) > - /* load round constants */ > - adr_l x8, .Lsha2_rcon > - ld1 { v0.4s- v3.4s}, [x8], #64 > - ld1 { v4.4s- v7.4s}, [x8], #64 > - ld1 { v8.4s-v11.4s}, [x8], #64 > - ld1 {v12.4s-v15.4s}, [x8] > + > + load_round_constants x8 > > /* load state */ > ld1 {dgav.4s, dgbv.4s}, [x0] > > /* load sha256_ce_state::finalize */ > @@ -153,5 +157,270 @@ CPU_LE( rev32 v19.16b, v19.16b ) > /* store new state */ > 3: st1 {dgav.4s, dgbv.4s}, [x0] > mov w0, w2 > ret > SYM_FUNC_END(__sha256_ce_transform) > + > + .unreq dga > + .unreq dgav > + .unreq dgb > + .unreq dgbv > + .unreq t0 > + .unreq t1 > + .unreq dg0q > + .unreq dg0v > + .unreq dg1q > + .unreq dg1v > + .unreq dg2q > + .unreq dg2v > + > + // parameters for __sha256_ce_finup2x() > + sctx .req x0 > + data1 .req x1 > + data2 .req x2 > + len .req w3 > + out1 .req x4 > + out2 .req x5 > + > + // other scalar variables > + count .req x6 > + final_step .req w7 > + > + // x8-x9 are used as temporaries. > + > + // v0-v15 are used to cache the SHA-256 round constants. > + // v16-v19 are used for the message schedule for the first message. > + // v20-v23 are used for the message schedule for the second message. > + // v24-v31 are used for the state and temporaries as given below. > + // *_a are for the first message and *_b for the second. > + state0_a_q .req q24 > + state0_a .req v24 > + state1_a_q .req q25 > + state1_a .req v25 > + state0_b_q .req q26 > + state0_b .req v26 > + state1_b_q .req q27 > + state1_b .req v27 > + t0_a .req v28 > + t0_b .req v29 > + t1_a_q .req q30 > + t1_a .req v30 > + t1_b_q .req q31 > + t1_b .req v31 > + > +#define OFFSETOF_COUNT 32 // offsetof(struct sha256_state, count) > +#define OFFSETOF_BUF 40 // offsetof(struct sha256_state, buf) > +// offsetof(struct sha256_state, state) is assumed to be 0. > + > + // Do 4 rounds of SHA-256 for each of two messages (interleaved). m0_a > + // and m0_b contain the current 4 message schedule words for the first > + // and second message respectively. > + // > + // If not all the message schedule words have been computed yet, then > + // this also computes 4 more message schedule words for each message. > + // m1_a-m3_a contain the next 3 groups of 4 message schedule words for > + // the first message, and likewise m1_b-m3_b for the second. After > + // consuming the current value of m0_a, this macro computes the group > + // after m3_a and writes it to m0_a, and likewise for *_b. This means > + // that the next (m0_a, m1_a, m2_a, m3_a) is the current (m1_a, m2_a, > + // m3_a, m0_a), and likewise for *_b, so the caller must cycle through > + // the registers accordingly. > + .macro do_4rounds_2x i, k, m0_a, m1_a, m2_a, m3_a, \ > + m0_b, m1_b, m2_b, m3_b > + add t0_a\().4s, \m0_a\().4s, \k\().4s > + add t0_b\().4s, \m0_b\().4s, \k\().4s > + .if \i < 48 > + sha256su0 \m0_a\().4s, \m1_a\().4s > + sha256su0 \m0_b\().4s, \m1_b\().4s > + sha256su1 \m0_a\().4s, \m2_a\().4s, \m3_a\().4s > + sha256su1 \m0_b\().4s, \m2_b\().4s, \m3_b\().4s > + .endif > + mov t1_a.16b, state0_a.16b > + mov t1_b.16b, state0_b.16b > + sha256h state0_a_q, state1_a_q, t0_a\().4s > + sha256h state0_b_q, state1_b_q, t0_b\().4s > + sha256h2 state1_a_q, t1_a_q, t0_a\().4s > + sha256h2 state1_b_q, t1_b_q, t0_b\().4s > + .endm > + > + .macro do_16rounds_2x i, k0, k1, k2, k3 > + do_4rounds_2x \i + 0, \k0, v16, v17, v18, v19, v20, v21, v22, v23 > + do_4rounds_2x \i + 4, \k1, v17, v18, v19, v16, v21, v22, v23, v20 > + do_4rounds_2x \i + 8, \k2, v18, v19, v16, v17, v22, v23, v20, v21 > + do_4rounds_2x \i + 12, \k3, v19, v16, v17, v18, v23, v20, v21, v22 > + .endm > + > +// > +// void __sha256_ce_finup2x(const struct sha256_state *sctx, > +// const u8 *data1, const u8 *data2, int len, > +// u8 out1[SHA256_DIGEST_SIZE], > +// u8 out2[SHA256_DIGEST_SIZE]); > +// > +// This function computes the SHA-256 digests of two messages |data1| and > +// |data2| that are both |len| bytes long, starting from the initial state > +// |sctx|. |len| must be at least SHA256_BLOCK_SIZE. > +// > +// The instructions for the two SHA-256 operations are interleaved. On many > +// CPUs, this is almost twice as fast as hashing each message individually due > +// to taking better advantage of the CPU's SHA-256 and SIMD throughput. > +// > +SYM_FUNC_START(__sha256_ce_finup2x) > + sub sp, sp, #128 > + mov final_step, #0 > + load_round_constants x8 > + > + // Load the initial state from sctx->state. > + ld1 {state0_a.4s-state1_a.4s}, [sctx] > + > + // Load sctx->count. Take the mod 64 of it to get the number of bytes > + // that are buffered in sctx->buf. Also save it in a register with len > + // added to it. > + ldr x8, [sctx, #OFFSETOF_COUNT] > + add count, x8, len, sxtw > + and x8, x8, #63 > + cbz x8, .Lfinup2x_enter_loop // No bytes buffered? > + > + // x8 bytes (1 to 63) are currently buffered in sctx->buf. Load them > + // followed by the first 64 - x8 bytes of data. Since len >= 64, we > + // just load 64 bytes from each of sctx->buf, data1, and data2 > + // unconditionally and rearrange the data as needed. > + add x9, sctx, #OFFSETOF_BUF > + ld1 {v16.16b-v19.16b}, [x9] > + st1 {v16.16b-v19.16b}, [sp] > + > + ld1 {v16.16b-v19.16b}, [data1], #64 > + add x9, sp, x8 > + st1 {v16.16b-v19.16b}, [x9] > + ld1 {v16.4s-v19.4s}, [sp] > + > + ld1 {v20.16b-v23.16b}, [data2], #64 > + st1 {v20.16b-v23.16b}, [x9] > + ld1 {v20.4s-v23.4s}, [sp] > + > + sub len, len, #64 > + sub data1, data1, x8 > + sub data2, data2, x8 > + add len, len, w8 > + mov state0_b.16b, state0_a.16b > + mov state1_b.16b, state1_a.16b > + b .Lfinup2x_loop_have_data > + > +.Lfinup2x_enter_loop: > + sub len, len, #64 > + mov state0_b.16b, state0_a.16b > + mov state1_b.16b, state1_a.16b > +.Lfinup2x_loop: > + // Load the next two data blocks. > + ld1 {v16.4s-v19.4s}, [data1], #64 > + ld1 {v20.4s-v23.4s}, [data2], #64 > +.Lfinup2x_loop_have_data: > + // Convert the words of the data blocks from big endian. > +CPU_LE( rev32 v16.16b, v16.16b ) > +CPU_LE( rev32 v17.16b, v17.16b ) > +CPU_LE( rev32 v18.16b, v18.16b ) > +CPU_LE( rev32 v19.16b, v19.16b ) > +CPU_LE( rev32 v20.16b, v20.16b ) > +CPU_LE( rev32 v21.16b, v21.16b ) > +CPU_LE( rev32 v22.16b, v22.16b ) > +CPU_LE( rev32 v23.16b, v23.16b ) > +.Lfinup2x_loop_have_bswapped_data: > + > + // Save the original state for each block. > + st1 {state0_a.4s-state1_b.4s}, [sp] > + > + // Do the SHA-256 rounds on each block. > + do_16rounds_2x 0, v0, v1, v2, v3 > + do_16rounds_2x 16, v4, v5, v6, v7 > + do_16rounds_2x 32, v8, v9, v10, v11 > + do_16rounds_2x 48, v12, v13, v14, v15 > + > + // Add the original state for each block. > + ld1 {v16.4s-v19.4s}, [sp] > + add state0_a.4s, state0_a.4s, v16.4s > + add state1_a.4s, state1_a.4s, v17.4s > + add state0_b.4s, state0_b.4s, v18.4s > + add state1_b.4s, state1_b.4s, v19.4s > + > + // Update len and loop back if more blocks remain. > + sub len, len, #64 > + tbz len, #31, .Lfinup2x_loop // len >= 0? > + > + // Check if any final blocks need to be handled. > + // final_step = 2: all done > + // final_step = 1: need to do count-only padding block > + // final_step = 0: need to do the block with 0x80 padding byte > + tbnz final_step, #1, .Lfinup2x_done > + tbnz final_step, #0, .Lfinup2x_finalize_countonly > + add len, len, #64 > + cbz len, .Lfinup2x_finalize_blockaligned > + > + // Not block-aligned; 1 <= len <= 63 data bytes remain. Pad the block. > + // To do this, write the padding starting with the 0x80 byte to > + // &sp[64]. Then for each message, copy the last 64 data bytes to sp > + // and load from &sp[64 - len] to get the needed padding block. This > + // code relies on the data buffers being >= 64 bytes in length. > + sub w8, len, #64 // w8 = len - 64 > + add data1, data1, w8, sxtw // data1 += len - 64 > + add data2, data2, w8, sxtw // data2 += len - 64 > + mov x9, 0x80 > + fmov d16, x9 > + movi v17.16b, #0 > + stp q16, q17, [sp, #64] > + stp q17, q17, [sp, #96] > + sub x9, sp, w8, sxtw // x9 = &sp[64 - len] > + cmp len, #56 > + b.ge 1f // will count spill into its own block? > + lsl count, count, #3 > + rev count, count > + str count, [x9, #56] > + mov final_step, #2 // won't need count-only block > + b 2f > +1: > + mov final_step, #1 // will need count-only block > +2: > + ld1 {v16.16b-v19.16b}, [data1] > + st1 {v16.16b-v19.16b}, [sp] > + ld1 {v16.4s-v19.4s}, [x9] > + ld1 {v20.16b-v23.16b}, [data2] > + st1 {v20.16b-v23.16b}, [sp] > + ld1 {v20.4s-v23.4s}, [x9] > + b .Lfinup2x_loop_have_data > + > + // Prepare a padding block, either: > + // > + // {0x80, 0, 0, 0, ..., count (as __be64)} > + // This is for a block aligned message. > + // > + // { 0, 0, 0, 0, ..., count (as __be64)} > + // This is for a message whose length mod 64 is >= 56. > + // > + // Pre-swap the endianness of the words. > +.Lfinup2x_finalize_countonly: > + movi v16.2d, #0 > + b 1f > +.Lfinup2x_finalize_blockaligned: > + mov x8, #0x80000000 > + fmov d16, x8 > +1: > + movi v17.2d, #0 > + movi v18.2d, #0 > + ror count, count, #29 // ror(lsl(count, 3), 32) > + mov v19.d[0], xzr > + mov v19.d[1], count > + mov v20.16b, v16.16b > + movi v21.2d, #0 > + movi v22.2d, #0 > + mov v23.16b, v19.16b > + mov final_step, #2 > + b .Lfinup2x_loop_have_bswapped_data > + > +.Lfinup2x_done: > + // Write the two digests with all bytes in the correct order. > +CPU_LE( rev32 state0_a.16b, state0_a.16b ) > +CPU_LE( rev32 state1_a.16b, state1_a.16b ) > +CPU_LE( rev32 state0_b.16b, state0_b.16b ) > +CPU_LE( rev32 state1_b.16b, state1_b.16b ) > + st1 {state0_a.4s-state1_a.4s}, [out1] > + st1 {state0_b.4s-state1_b.4s}, [out2] > + add sp, sp, #128 > + ret > +SYM_FUNC_END(__sha256_ce_finup2x) > diff --git a/arch/arm64/crypto/sha2-ce-glue.c b/arch/arm64/crypto/sha2-ce-glue.c > index 0a44d2e7ee1f..b37cffc4191f 100644 > --- a/arch/arm64/crypto/sha2-ce-glue.c > +++ b/arch/arm64/crypto/sha2-ce-glue.c > @@ -31,10 +31,15 @@ extern const u32 sha256_ce_offsetof_count; > extern const u32 sha256_ce_offsetof_finalize; > > asmlinkage int __sha256_ce_transform(struct sha256_ce_state *sst, u8 const *src, > int blocks); > > +asmlinkage void __sha256_ce_finup2x(const struct sha256_state *sctx, > + const u8 *data1, const u8 *data2, int len, > + u8 out1[SHA256_DIGEST_SIZE], > + u8 out2[SHA256_DIGEST_SIZE]); > + > static void sha256_ce_transform(struct sha256_state *sst, u8 const *src, > int blocks) > { > while (blocks) { > int rem; > @@ -122,10 +127,43 @@ static int sha256_ce_digest(struct shash_desc *desc, const u8 *data, > { > sha256_base_init(desc); > return sha256_ce_finup(desc, data, len, out); > } > > +static int sha256_ce_finup_mb(struct shash_desc *desc, > + const u8 * const data[], unsigned int len, > + u8 * const outs[], unsigned int num_msgs) > +{ > + struct sha256_ce_state *sctx = shash_desc_ctx(desc); > + > + /* > + * num_msgs != 2 should not happen here, since this algorithm sets > + * mb_max_msgs=2, and the crypto API handles num_msgs <= 1 before > + * calling into the algorithm's finup_mb method. > + */ > + if (WARN_ON_ONCE(num_msgs != 2)) > + return -EOPNOTSUPP; > + > + if (unlikely(!crypto_simd_usable())) > + return -EOPNOTSUPP; > + > + /* __sha256_ce_finup2x() assumes SHA256_BLOCK_SIZE <= len <= INT_MAX. */ > + if (unlikely(len < SHA256_BLOCK_SIZE || len > INT_MAX)) > + return -EOPNOTSUPP; > + > + /* __sha256_ce_finup2x() assumes the following offsets. */ > + BUILD_BUG_ON(offsetof(struct sha256_state, state) != 0); > + BUILD_BUG_ON(offsetof(struct sha256_state, count) != 32); > + BUILD_BUG_ON(offsetof(struct sha256_state, buf) != 40); > + > + kernel_neon_begin(); > + __sha256_ce_finup2x(&sctx->sst, data[0], data[1], len, outs[0], > + outs[1]); > + kernel_neon_end(); > + return 0; > +} > + > static int sha256_ce_export(struct shash_desc *desc, void *out) > { > struct sha256_ce_state *sctx = shash_desc_ctx(desc); > > memcpy(out, &sctx->sst, sizeof(struct sha256_state)); > @@ -162,13 +200,15 @@ static struct shash_alg algs[] = { { > .init = sha256_base_init, > .update = sha256_ce_update, > .final = sha256_ce_final, > .finup = sha256_ce_finup, > .digest = sha256_ce_digest, > + .finup_mb = sha256_ce_finup_mb, > .export = sha256_ce_export, > .import = sha256_ce_import, > .descsize = sizeof(struct sha256_ce_state), > + .mb_max_msgs = 2, > .statesize = sizeof(struct sha256_state), > .digestsize = SHA256_DIGEST_SIZE, > .base = { > .cra_name = "sha256", > .cra_driver_name = "sha256-ce", > -- > 2.45.1 >