From 464a6f99943ecce4387d83a37e701be4f1864b6f Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Tue, 25 Feb 2025 22:28:40 -0800 Subject: [PATCH] nvmet-tcp: switch to using the crc32c library Now that the crc32c() library function directly takes advantage of architecture-specific optimizations, it is unnecessary to go through the crypto API. Just use crc32c(). This is much simpler, and it improves performance due to eliminating the crypto API overhead. Signed-off-by: Eric Biggers Reviewed-by: Sagi Grimberg Reviewed-by: Hannes Reinecke Signed-off-by: Christoph Hellwig --- drivers/nvme/target/tcp.c | 92 +++++++++++---------------------------- 1 file changed, 26 insertions(+), 66 deletions(-) diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c index f2d0c920269b..1d34e839e1ec 100644 --- a/drivers/nvme/target/tcp.c +++ b/drivers/nvme/target/tcp.c @@ -7,6 +7,7 @@ #include #include #include +#include #include #include #include @@ -17,7 +18,6 @@ #include #include #include -#include #include #include "nvmet.h" @@ -172,8 +172,6 @@ struct nvmet_tcp_queue { /* digest state */ bool hdr_digest; bool data_digest; - struct ahash_request *snd_hash; - struct ahash_request *rcv_hash; /* TLS state */ key_serial_t tls_pskid; @@ -294,14 +292,9 @@ static inline u8 nvmet_tcp_ddgst_len(struct nvmet_tcp_queue *queue) return queue->data_digest ? NVME_TCP_DIGEST_LENGTH : 0; } -static inline void nvmet_tcp_hdgst(struct ahash_request *hash, - void *pdu, size_t len) +static inline void nvmet_tcp_hdgst(void *pdu, size_t len) { - struct scatterlist sg; - - sg_init_one(&sg, pdu, len); - ahash_request_set_crypt(hash, &sg, pdu + len, len); - crypto_ahash_digest(hash); + put_unaligned_le32(~crc32c(~0, pdu, len), pdu + len); } static int nvmet_tcp_verify_hdgst(struct nvmet_tcp_queue *queue, @@ -318,7 +311,7 @@ static int nvmet_tcp_verify_hdgst(struct nvmet_tcp_queue *queue, } recv_digest = *(__le32 *)(pdu + hdr->hlen); - nvmet_tcp_hdgst(queue->rcv_hash, pdu, len); + nvmet_tcp_hdgst(pdu, len); exp_digest = *(__le32 *)(pdu + hdr->hlen); if (recv_digest != exp_digest) { pr_err("queue %d: header digest error: recv %#x expected %#x\n", @@ -441,12 +434,24 @@ err: return NVME_SC_INTERNAL; } -static void nvmet_tcp_calc_ddgst(struct ahash_request *hash, - struct nvmet_tcp_cmd *cmd) +static void nvmet_tcp_calc_ddgst(struct nvmet_tcp_cmd *cmd) { - ahash_request_set_crypt(hash, cmd->req.sg, - (void *)&cmd->exp_ddgst, cmd->req.transfer_len); - crypto_ahash_digest(hash); + size_t total_len = cmd->req.transfer_len; + struct scatterlist *sg = cmd->req.sg; + u32 crc = ~0; + + while (total_len) { + size_t len = min_t(size_t, total_len, sg->length); + + /* + * Note that the scatterlist does not contain any highmem pages, + * as it was allocated by sgl_alloc() with GFP_KERNEL. + */ + crc = crc32c(crc, sg_virt(sg), len); + total_len -= len; + sg = sg_next(sg); + } + cmd->exp_ddgst = cpu_to_le32(~crc); } static void nvmet_setup_c2h_data_pdu(struct nvmet_tcp_cmd *cmd) @@ -473,19 +478,18 @@ static void nvmet_setup_c2h_data_pdu(struct nvmet_tcp_cmd *cmd) if (queue->data_digest) { pdu->hdr.flags |= NVME_TCP_F_DDGST; - nvmet_tcp_calc_ddgst(queue->snd_hash, cmd); + nvmet_tcp_calc_ddgst(cmd); } if (cmd->queue->hdr_digest) { pdu->hdr.flags |= NVME_TCP_F_HDGST; - nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu)); + nvmet_tcp_hdgst(pdu, sizeof(*pdu)); } } static void nvmet_setup_r2t_pdu(struct nvmet_tcp_cmd *cmd) { struct nvme_tcp_r2t_pdu *pdu = cmd->r2t_pdu; - struct nvmet_tcp_queue *queue = cmd->queue; u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); cmd->offset = 0; @@ -503,14 +507,13 @@ static void nvmet_setup_r2t_pdu(struct nvmet_tcp_cmd *cmd) pdu->r2t_offset = cpu_to_le32(cmd->rbytes_done); if (cmd->queue->hdr_digest) { pdu->hdr.flags |= NVME_TCP_F_HDGST; - nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu)); + nvmet_tcp_hdgst(pdu, sizeof(*pdu)); } } static void nvmet_setup_response_pdu(struct nvmet_tcp_cmd *cmd) { struct nvme_tcp_rsp_pdu *pdu = cmd->rsp_pdu; - struct nvmet_tcp_queue *queue = cmd->queue; u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); cmd->offset = 0; @@ -523,7 +526,7 @@ static void nvmet_setup_response_pdu(struct nvmet_tcp_cmd *cmd) pdu->hdr.plen = cpu_to_le32(pdu->hdr.hlen + hdgst); if (cmd->queue->hdr_digest) { pdu->hdr.flags |= NVME_TCP_F_HDGST; - nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu)); + nvmet_tcp_hdgst(pdu, sizeof(*pdu)); } } @@ -857,42 +860,6 @@ static void nvmet_prepare_receive_pdu(struct nvmet_tcp_queue *queue) smp_store_release(&queue->rcv_state, NVMET_TCP_RECV_PDU); } -static void nvmet_tcp_free_crypto(struct nvmet_tcp_queue *queue) -{ - struct crypto_ahash *tfm = crypto_ahash_reqtfm(queue->rcv_hash); - - ahash_request_free(queue->rcv_hash); - ahash_request_free(queue->snd_hash); - crypto_free_ahash(tfm); -} - -static int nvmet_tcp_alloc_crypto(struct nvmet_tcp_queue *queue) -{ - struct crypto_ahash *tfm; - - tfm = crypto_alloc_ahash("crc32c", 0, CRYPTO_ALG_ASYNC); - if (IS_ERR(tfm)) - return PTR_ERR(tfm); - - queue->snd_hash = ahash_request_alloc(tfm, GFP_KERNEL); - if (!queue->snd_hash) - goto free_tfm; - ahash_request_set_callback(queue->snd_hash, 0, NULL, NULL); - - queue->rcv_hash = ahash_request_alloc(tfm, GFP_KERNEL); - if (!queue->rcv_hash) - goto free_snd_hash; - ahash_request_set_callback(queue->rcv_hash, 0, NULL, NULL); - - return 0; -free_snd_hash: - ahash_request_free(queue->snd_hash); -free_tfm: - crypto_free_ahash(tfm); - return -ENOMEM; -} - - static int nvmet_tcp_handle_icreq(struct nvmet_tcp_queue *queue) { struct nvme_tcp_icreq_pdu *icreq = &queue->pdu.icreq; @@ -921,11 +888,6 @@ static int nvmet_tcp_handle_icreq(struct nvmet_tcp_queue *queue) queue->hdr_digest = !!(icreq->digest & NVME_TCP_HDR_DIGEST_ENABLE); queue->data_digest = !!(icreq->digest & NVME_TCP_DATA_DIGEST_ENABLE); - if (queue->hdr_digest || queue->data_digest) { - ret = nvmet_tcp_alloc_crypto(queue); - if (ret) - return ret; - } memset(icresp, 0, sizeof(*icresp)); icresp->hdr.type = nvme_tcp_icresp; @@ -1247,7 +1209,7 @@ static void nvmet_tcp_prep_recv_ddgst(struct nvmet_tcp_cmd *cmd) { struct nvmet_tcp_queue *queue = cmd->queue; - nvmet_tcp_calc_ddgst(queue->rcv_hash, cmd); + nvmet_tcp_calc_ddgst(cmd); queue->offset = 0; queue->left = NVME_TCP_DIGEST_LENGTH; queue->rcv_state = NVMET_TCP_RECV_DDGST; @@ -1617,8 +1579,6 @@ static void nvmet_tcp_release_queue_work(struct work_struct *w) /* ->sock will be released by fput() */ fput(queue->sock->file); nvmet_tcp_free_cmds(queue); - if (queue->hdr_digest || queue->data_digest) - nvmet_tcp_free_crypto(queue); ida_free(&nvmet_tcp_queue_ida, queue->idx); page_frag_cache_drain(&queue->pf_cache); kfree(queue); -- 2.49.0