iscsi-target: Refactor ISCSI_OP_TEXT_RSP TX handling
This patch refactoring existing iscsit_send_text_rsp() in order
to handle iscsi_text_rsp payloads in a transport specific manner.
This includes the addition of iscsit_build_text_rsp() to build
the response payload and initialize ISCSI_OP_TEXT_RSP.
v2: Make iscsit_build_text_rsp() determine extra padding bytes, and
drop legacy padding calculation for traditional iSCSI text
responses within iscsit_send_text_rsp()
Reported-by: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c
index ae312c5..1f79a16 100644
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -3461,6 +3461,37 @@
return payload_len;
}
+int
+iscsit_build_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
+ struct iscsi_text_rsp *hdr)
+{
+ int text_length, padding;
+
+ text_length = iscsit_build_sendtargets_response(cmd);
+ if (text_length < 0)
+ return text_length;
+
+ hdr->opcode = ISCSI_OP_TEXT_RSP;
+ hdr->flags |= ISCSI_FLAG_CMD_FINAL;
+ padding = ((-text_length) & 3);
+ hton24(hdr->dlength, text_length);
+ hdr->itt = cmd->init_task_tag;
+ hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
+ cmd->stat_sn = conn->stat_sn++;
+ hdr->statsn = cpu_to_be32(cmd->stat_sn);
+
+ iscsit_increment_maxcmdsn(cmd, conn->sess);
+ hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
+ hdr->max_cmdsn = cpu_to_be32(conn->sess->max_cmd_sn);
+
+ pr_debug("Built Text Response: ITT: 0x%08x, StatSN: 0x%08x,"
+ " Length: %u, CID: %hu\n", cmd->init_task_tag, cmd->stat_sn,
+ text_length, conn->cid);
+
+ return text_length + padding;
+}
+EXPORT_SYMBOL(iscsit_build_text_rsp);
+
/*
* FIXME: Add support for F_BIT and C_BIT when the length is longer than
* MaxRecvDataSegmentLength.
@@ -3469,44 +3500,23 @@
struct iscsi_cmd *cmd,
struct iscsi_conn *conn)
{
- struct iscsi_text_rsp *hdr;
+ struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
struct kvec *iov;
- u32 padding = 0, tx_size = 0;
- int text_length, iov_count = 0;
+ u32 tx_size = 0;
+ int text_length, iov_count = 0, rc;
- text_length = iscsit_build_sendtargets_response(cmd);
- if (text_length < 0)
- return text_length;
+ rc = iscsit_build_text_rsp(cmd, conn, hdr);
+ if (rc < 0)
+ return rc;
- padding = ((-text_length) & 3);
- if (padding != 0) {
- memset(cmd->buf_ptr + text_length, 0, padding);
- pr_debug("Attaching %u additional bytes for"
- " padding.\n", padding);
- }
-
- hdr = (struct iscsi_text_rsp *) cmd->pdu;
- memset(hdr, 0, ISCSI_HDR_LEN);
- hdr->opcode = ISCSI_OP_TEXT_RSP;
- hdr->flags |= ISCSI_FLAG_CMD_FINAL;
- hton24(hdr->dlength, text_length);
- hdr->itt = cmd->init_task_tag;
- hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
- cmd->stat_sn = conn->stat_sn++;
- hdr->statsn = cpu_to_be32(cmd->stat_sn);
-
- iscsit_increment_maxcmdsn(cmd, conn->sess);
- hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
- hdr->max_cmdsn = cpu_to_be32(conn->sess->max_cmd_sn);
-
+ text_length = rc;
iov = &cmd->iov_misc[0];
-
iov[iov_count].iov_base = cmd->pdu;
iov[iov_count++].iov_len = ISCSI_HDR_LEN;
iov[iov_count].iov_base = cmd->buf_ptr;
- iov[iov_count++].iov_len = text_length + padding;
+ iov[iov_count++].iov_len = text_length;
- tx_size += (ISCSI_HDR_LEN + text_length + padding);
+ tx_size += (ISCSI_HDR_LEN + text_length);
if (conn->conn_ops->HeaderDigest) {
u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
@@ -3522,7 +3532,7 @@
if (conn->conn_ops->DataDigest) {
iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
- cmd->buf_ptr, (text_length + padding),
+ cmd->buf_ptr, text_length,
0, NULL, (u8 *)&cmd->data_crc);
iov[iov_count].iov_base = &cmd->data_crc;
@@ -3530,16 +3540,13 @@
tx_size += ISCSI_CRC_LEN;
pr_debug("Attaching DataDigest for %u bytes of text"
- " data, CRC 0x%08x\n", (text_length + padding),
+ " data, CRC 0x%08x\n", text_length,
cmd->data_crc);
}
cmd->iov_misc_count = iov_count;
cmd->tx_size = tx_size;
- pr_debug("Built Text Response: ITT: 0x%08x, StatSN: 0x%08x,"
- " Length: %u, CID: %hu\n", cmd->init_task_tag, cmd->stat_sn,
- text_length, conn->cid);
return 0;
}
diff --git a/include/target/iscsi/iscsi_transport.h b/include/target/iscsi/iscsi_transport.h
index 90f3b60..ce991ba 100644
--- a/include/target/iscsi/iscsi_transport.h
+++ b/include/target/iscsi/iscsi_transport.h
@@ -63,6 +63,8 @@
struct iscsi_nopin *, bool);
extern void iscsit_build_task_mgt_rsp(struct iscsi_cmd *, struct iscsi_conn *,
struct iscsi_tm_rsp *);
+extern int iscsit_build_text_rsp(struct iscsi_cmd *, struct iscsi_conn *,
+ struct iscsi_text_rsp *);
extern void iscsit_build_reject(struct iscsi_cmd *, struct iscsi_conn *,
struct iscsi_reject *);
extern int iscsit_build_logout_rsp(struct iscsi_cmd *, struct iscsi_conn *,