scsi: target: iscsi: 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.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20241202010844.144356-20-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>

diff --git a/drivers/target/iscsi/Kconfig b/drivers/target/iscsi/Kconfig
index 1c0517a125713a59c9ba1d0c3f1ac424e9db8c3d..70d76f3dd6939ab22459850ea1488b9c11905beb 100644 (file)
--- a/drivers/target/iscsi/Kconfig
+++ b/drivers/target/iscsi/Kconfig
@@ -2,8 +2,9 @@
 config ISCSI_TARGET
        tristate "SCSI Target Mode Stack"
        depends on INET
+       select CRC32
        select CRYPTO
-       select CRYPTO_CRC32C
+       select CRYPTO_HASH
        help
        Say M to enable the SCSI target mode stack. A SCSI target mode stack
        is software that makes local storage available over a storage network

diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c
index 6002283cbebabc474b405a21ab2b1960c33cb836..091c1efccfb7b2c032544a04bb9c18a9e9094893 100644 (file)
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -8,7 +8,7 @@
  *
  ******************************************************************************/
 
-#include <crypto/hash.h>
+#include <linux/crc32c.h>
 #include <linux/string.h>
 #include <linux/kthread.h>
 #include <linux/completion.h>
@@ -490,8 +490,8 @@ void iscsit_aborted_task(struct iscsit_conn *conn, struct iscsit_cmd *cmd)
 }
 EXPORT_SYMBOL(iscsit_aborted_task);
 
-static void iscsit_do_crypto_hash_buf(struct ahash_request *, const void *,
-                                     u32, u32, const void *, void *);
+static u32 iscsit_crc_buf(const void *buf, u32 payload_length,
+                         u32 padding, const void *pad_bytes);
 static void iscsit_tx_thread_wait_for_tcp(struct iscsit_conn *);
 
 static int
@@ -510,9 +510,7 @@ iscsit_xmit_nondatain_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
        if (conn->conn_ops->HeaderDigest) {
                u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
 
-               iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
-                                         ISCSI_HDR_LEN, 0, NULL,
-                                         header_digest);
+               *header_digest = iscsit_crc_buf(hdr, ISCSI_HDR_LEN, 0, NULL);
 
                iov[0].iov_len += ISCSI_CRC_LEN;
                tx_size += ISCSI_CRC_LEN;
@@ -537,11 +535,9 @@ iscsit_xmit_nondatain_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
                }
 
                if (conn->conn_ops->DataDigest) {
-                       iscsit_do_crypto_hash_buf(conn->conn_tx_hash,
-                                                 data_buf, data_buf_len,
-                                                 padding, &cmd->pad_bytes,
-                                                 &cmd->data_crc);
-
+                       cmd->data_crc = iscsit_crc_buf(data_buf, data_buf_len,
+                                                      padding,
+                                                      &cmd->pad_bytes);
                        iov[niov].iov_base = &cmd->data_crc;
                        iov[niov++].iov_len = ISCSI_CRC_LEN;
                        tx_size += ISCSI_CRC_LEN;
@@ -566,8 +562,8 @@ iscsit_xmit_nondatain_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
 static int iscsit_map_iovec(struct iscsit_cmd *cmd, struct kvec *iov, int nvec,
                            u32 data_offset, u32 data_length);
 static void iscsit_unmap_iovec(struct iscsit_cmd *);
-static u32 iscsit_do_crypto_hash_sg(struct ahash_request *, struct iscsit_cmd *,
-                                   u32, u32, u32, u8 *);
+static u32 iscsit_crc_sglist(const struct iscsit_cmd *cmd, u32 data_length,
+                            u32 padding, const u8 *pad_bytes);
 static int
 iscsit_xmit_datain_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
                       const struct iscsi_datain *datain)
@@ -584,10 +580,8 @@ iscsit_xmit_datain_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
        if (conn->conn_ops->HeaderDigest) {
                u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
 
-               iscsit_do_crypto_hash_buf(conn->conn_tx_hash, cmd->pdu,
-                                         ISCSI_HDR_LEN, 0, NULL,
-                                         header_digest);
-
+               *header_digest = iscsit_crc_buf(cmd->pdu, ISCSI_HDR_LEN, 0,
+                                               NULL);
                iov[0].iov_len += ISCSI_CRC_LEN;
                tx_size += ISCSI_CRC_LEN;
 
@@ -614,12 +608,8 @@ iscsit_xmit_datain_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
        }
 
        if (conn->conn_ops->DataDigest) {
-               cmd->data_crc = iscsit_do_crypto_hash_sg(conn->conn_tx_hash,
-                                                        cmd, datain->offset,
-                                                        datain->length,
-                                                        cmd->padding,
-                                                        cmd->pad_bytes);
-
+               cmd->data_crc = iscsit_crc_sglist(cmd, datain->length,
+                                                 cmd->padding, cmd->pad_bytes);
                iov[iov_count].iov_base = &cmd->data_crc;
                iov[iov_count++].iov_len = ISCSI_CRC_LEN;
                tx_size += ISCSI_CRC_LEN;
@@ -1404,77 +1394,45 @@ iscsit_handle_scsi_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
        return iscsit_get_immediate_data(cmd, hdr, dump_payload);
 }
 
-static u32 iscsit_do_crypto_hash_sg(
-       struct ahash_request *hash,
-       struct iscsit_cmd *cmd,
-       u32 data_offset,
-       u32 data_length,
-       u32 padding,
-       u8 *pad_bytes)
+static u32 iscsit_crc_sglist(const struct iscsit_cmd *cmd, u32 data_length,
+                            u32 padding, const u8 *pad_bytes)
 {
-       u32 data_crc;
-       struct scatterlist *sg;
-       unsigned int page_off;
-
-       crypto_ahash_init(hash);
-
-       sg = cmd->first_data_sg;
-       page_off = cmd->first_data_sg_off;
-
-       if (data_length && page_off) {
-               struct scatterlist first_sg;
-               u32 len = min_t(u32, data_length, sg->length - page_off);
-
-               sg_init_table(&first_sg, 1);
-               sg_set_page(&first_sg, sg_page(sg), len, sg->offset + page_off);
-
-               ahash_request_set_crypt(hash, &first_sg, NULL, len);
-               crypto_ahash_update(hash);
-
-               data_length -= len;
-               sg = sg_next(sg);
-       }
+       struct scatterlist *sg = cmd->first_data_sg;
+       unsigned int page_off = cmd->first_data_sg_off;
+       u32 crc = ~0;
 
        while (data_length) {
-               u32 cur_len = min_t(u32, data_length, sg->length);
+               u32 cur_len = min_t(u32, data_length, sg->length - page_off);
+               const void *virt;
 
-               ahash_request_set_crypt(hash, sg, NULL, cur_len);
-               crypto_ahash_update(hash);
+               virt = kmap_local_page(sg_page(sg)) + sg->offset + page_off;
+               crc = crc32c(crc, virt, cur_len);
+               kunmap_local(virt);
 
-               data_length -= cur_len;
                /* iscsit_map_iovec has already checked for invalid sg pointers */
                sg = sg_next(sg);
-       }
 
-       if (padding) {
-               struct scatterlist pad_sg;
-
-               sg_init_one(&pad_sg, pad_bytes, padding);
-               ahash_request_set_crypt(hash, &pad_sg, (u8 *)&data_crc,
-                                       padding);
-               crypto_ahash_finup(hash);
-       } else {
-               ahash_request_set_crypt(hash, NULL, (u8 *)&data_crc, 0);
-               crypto_ahash_final(hash);
+               page_off = 0;
+               data_length -= cur_len;
        }
 
-       return data_crc;
+       if (padding)
+               crc = crc32c(crc, pad_bytes, padding);
+
+       return ~crc;
 }
 
-static void iscsit_do_crypto_hash_buf(struct ahash_request *hash,
-       const void *buf, u32 payload_length, u32 padding,
-       const void *pad_bytes, void *data_crc)
+static u32 iscsit_crc_buf(const void *buf, u32 payload_length,
+                         u32 padding, const void *pad_bytes)
 {
-       struct scatterlist sg[2];
+       u32 crc = ~0;
 
-       sg_init_table(sg, ARRAY_SIZE(sg));
-       sg_set_buf(sg, buf, payload_length);
-       if (padding)
-               sg_set_buf(sg + 1, pad_bytes, padding);
+       crc = crc32c(crc, buf, payload_length);
 
-       ahash_request_set_crypt(hash, sg, data_crc, payload_length + padding);
+       if (padding)
+               crc = crc32c(crc, pad_bytes, padding);
 
-       crypto_ahash_digest(hash);
+       return ~crc;
 }
 
 int
@@ -1662,11 +1620,8 @@ iscsit_get_dataout(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
        if (conn->conn_ops->DataDigest) {
                u32 data_crc;
 
-               data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
-                                                   be32_to_cpu(hdr->offset),
-                                                   payload_length, padding,
-                                                   cmd->pad_bytes);
-
+               data_crc = iscsit_crc_sglist(cmd, payload_length, padding,
+                                            cmd->pad_bytes);
                if (checksum != data_crc) {
                        pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
                                " DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
@@ -1925,10 +1880,8 @@ static int iscsit_handle_nop_out(struct iscsit_conn *conn, struct iscsit_cmd *cm
                }
 
                if (conn->conn_ops->DataDigest) {
-                       iscsit_do_crypto_hash_buf(conn->conn_rx_hash, ping_data,
-                                                 payload_length, padding,
-                                                 cmd->pad_bytes, &data_crc);
-
+                       data_crc = iscsit_crc_buf(ping_data, payload_length,
+                                                 padding, cmd->pad_bytes);
                        if (checksum != data_crc) {
                                pr_err("Ping data CRC32C DataDigest"
                                " 0x%08x does not match computed 0x%08x\n",
@@ -2328,10 +2281,7 @@ iscsit_handle_text_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
                        goto reject;
 
                if (conn->conn_ops->DataDigest) {
-                       iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
-                                                 text_in, rx_size, 0, NULL,
-                                                 &data_crc);
-
+                       data_crc = iscsit_crc_buf(text_in, rx_size, 0, NULL);
                        if (checksum != data_crc) {
                                pr_err("Text data CRC32C DataDigest"
                                        " 0x%08x does not match computed"
@@ -2688,10 +2638,8 @@ static int iscsit_handle_immediate_data(
        if (conn->conn_ops->DataDigest) {
                u32 data_crc;
 
-               data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
-                                                   cmd->write_data_done, length, padding,
-                                                   cmd->pad_bytes);
-
+               data_crc = iscsit_crc_sglist(cmd, length, padding,
+                                            cmd->pad_bytes);
                if (checksum != data_crc) {
                        pr_err("ImmediateData CRC32C DataDigest 0x%08x"
                                " does not match computed 0x%08x\n", checksum,
@@ -4116,10 +4064,8 @@ static void iscsit_get_rx_pdu(struct iscsit_conn *conn)
                                break;
                        }
 
-                       iscsit_do_crypto_hash_buf(conn->conn_rx_hash, buffer,
-                                                 ISCSI_HDR_LEN, 0, NULL,
-                                                 &checksum);
-
+                       checksum = iscsit_crc_buf(buffer, ISCSI_HDR_LEN, 0,
+                                                 NULL);
                        if (digest != checksum) {
                                pr_err("HeaderDigest CRC32C failed,"
                                        " received 0x%08x, computed 0x%08x\n",
@@ -4406,15 +4352,6 @@ int iscsit_close_connection(
         */
        iscsit_check_conn_usage_count(conn);
 
-       ahash_request_free(conn->conn_tx_hash);
-       if (conn->conn_rx_hash) {
-               struct crypto_ahash *tfm;
-
-               tfm = crypto_ahash_reqtfm(conn->conn_rx_hash);
-               ahash_request_free(conn->conn_rx_hash);
-               crypto_free_ahash(tfm);
-       }
-
        if (conn->sock)
                sock_release(conn->sock);
 

diff --git a/drivers/target/iscsi/iscsi_target_login.c b/drivers/target/iscsi/iscsi_target_login.c
index 90b870f234f03cd9033418387482a34bf9d4ede1..c2ac9a99ebbb2927b56317ff04ef20771d316617 100644 (file)
--- a/drivers/target/iscsi/iscsi_target_login.c
+++ b/drivers/target/iscsi/iscsi_target_login.c
@@ -8,7 +8,6 @@
  *
  ******************************************************************************/
 
-#include <crypto/hash.h>
 #include <linux/module.h>
 #include <linux/string.h>
 #include <linux/kthread.h>
@@ -71,46 +70,6 @@ out_login:
        return NULL;
 }
 
-/*
- * Used by iscsi_target_nego.c:iscsi_target_locate_portal() to setup
- * per struct iscsit_conn libcrypto contexts for crc32c and crc32-intel
- */
-int iscsi_login_setup_crypto(struct iscsit_conn *conn)
-{
-       struct crypto_ahash *tfm;
-
-       /*
-        * Setup slicing by CRC32C algorithm for RX and TX libcrypto contexts
-        * which will default to crc32c_intel.ko for cpu_has_xmm4_2, or fallback
-        * to software 1x8 byte slicing from crc32c.ko
-        */
-       tfm = crypto_alloc_ahash("crc32c", 0, CRYPTO_ALG_ASYNC);
-       if (IS_ERR(tfm)) {
-               pr_err("crypto_alloc_ahash() failed\n");
-               return -ENOMEM;
-       }
-
-       conn->conn_rx_hash = ahash_request_alloc(tfm, GFP_KERNEL);
-       if (!conn->conn_rx_hash) {
-               pr_err("ahash_request_alloc() failed for conn_rx_hash\n");
-               crypto_free_ahash(tfm);
-               return -ENOMEM;
-       }
-       ahash_request_set_callback(conn->conn_rx_hash, 0, NULL, NULL);
-
-       conn->conn_tx_hash = ahash_request_alloc(tfm, GFP_KERNEL);
-       if (!conn->conn_tx_hash) {
-               pr_err("ahash_request_alloc() failed for conn_tx_hash\n");
-               ahash_request_free(conn->conn_rx_hash);
-               conn->conn_rx_hash = NULL;
-               crypto_free_ahash(tfm);
-               return -ENOMEM;
-       }
-       ahash_request_set_callback(conn->conn_tx_hash, 0, NULL, NULL);
-
-       return 0;
-}
-
 static int iscsi_login_check_initiator_version(
        struct iscsit_conn *conn,
        u8 version_max,
@@ -1165,15 +1124,6 @@ old_sess_out:
                iscsit_dec_session_usage_count(conn->sess);
        }
 
-       ahash_request_free(conn->conn_tx_hash);
-       if (conn->conn_rx_hash) {
-               struct crypto_ahash *tfm;
-
-               tfm = crypto_ahash_reqtfm(conn->conn_rx_hash);
-               ahash_request_free(conn->conn_rx_hash);
-               crypto_free_ahash(tfm);
-       }
-
        if (conn->param_list) {
                iscsi_release_param_list(conn->param_list);
                conn->param_list = NULL;

diff --git a/drivers/target/iscsi/iscsi_target_login.h b/drivers/target/iscsi/iscsi_target_login.h
index e8760735486bc9fbec7dd3d9a7906824c4ff749f..03c7d695d58f1abd867fd5fbd7e2b192e3778e45 100644 (file)
--- a/drivers/target/iscsi/iscsi_target_login.h
+++ b/drivers/target/iscsi/iscsi_target_login.h
@@ -9,7 +9,6 @@ struct iscsi_login;
 struct iscsi_np;
 struct sockaddr_storage;
 
-extern int iscsi_login_setup_crypto(struct iscsit_conn *);
 extern int iscsi_check_for_session_reinstatement(struct iscsit_conn *);
 extern int iscsi_login_post_auth_non_zero_tsih(struct iscsit_conn *, u16, u32);
 extern int iscsit_setup_np(struct iscsi_np *,

diff --git a/drivers/target/iscsi/iscsi_target_nego.c b/drivers/target/iscsi/iscsi_target_nego.c
index fa3fb5f4e6bc44db94eb42740dec672c099dd889..16e3ded98c32a1666903705c75f8e1198189b154 100644 (file)
--- a/drivers/target/iscsi/iscsi_target_nego.c
+++ b/drivers/target/iscsi/iscsi_target_nego.c
@@ -1194,14 +1194,7 @@ int iscsi_target_locate_portal(
                        goto get_target;
 
                sess->sess_ops->SessionType = 1;
-               /*
-                * Setup crc32c modules from libcrypto
-                */
-               if (iscsi_login_setup_crypto(conn) < 0) {
-                       pr_err("iscsi_login_setup_crypto() failed\n");
-                       ret = -1;
-                       goto out;
-               }
+
                /*
                 * Serialize access across the discovery struct iscsi_portal_group to
                 * process login attempt.
@@ -1258,17 +1251,7 @@ get_target:
        }
        conn->tpg_np = tpg_np;
        pr_debug("Located Portal Group Object: %hu\n", conn->tpg->tpgt);
-       /*
-        * Setup crc32c modules from libcrypto
-        */
-       if (iscsi_login_setup_crypto(conn) < 0) {
-               pr_err("iscsi_login_setup_crypto() failed\n");
-               kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
-               iscsit_put_tiqn_for_login(tiqn);
-               conn->tpg = NULL;
-               ret = -1;
-               goto out;
-       }
+
        /*
         * Serialize access across the struct iscsi_portal_group to
         * process login attempt.

diff --git a/include/target/iscsi/iscsi_target_core.h b/include/target/iscsi/iscsi_target_core.h
index 60af7c63b34e6afaff10a0c25e8fc8fd843ee93b..51ca80abacf7ba5ef53e0038b7fcbadde390e854 100644 (file)
--- a/include/target/iscsi/iscsi_target_core.h
+++ b/include/target/iscsi/iscsi_target_core.h
@@ -576,9 +576,6 @@ struct iscsit_conn {
        spinlock_t              state_lock;
        spinlock_t              login_timer_lock;
        spinlock_t              login_worker_lock;
-       /* libcrypto RX and TX contexts for crc32c */
-       struct ahash_request    *conn_rx_hash;
-       struct ahash_request    *conn_tx_hash;
        /* Used for scheduling TX and RX connection kthreads */
        cpumask_var_t           conn_cpumask;
        cpumask_var_t           allowed_cpumask;