target/iscsi: split iscsit_check_dataout_hdr()

Split iscsit_check_dataout_hdr() into two functions
1. __iscsit_check_dataout_hdr() - This function
   validates data out hdr.
2. iscsit_check_dataout_hdr() - This function finds
   iSCSI cmd using iscsit_find_cmd_from_itt_or_dump(),
   then it calls __iscsit_check_dataout_hdr() to
   validate iSCSI hdr.

This split is required to support Chelsio T6 iSCSI
DDP completion feature. T6 adapters reduce number of
completions to host by generating single completion
for all directly placed(DDP) iSCSI pdus in a sequence,
DDP completion contains iSCSI hdr of the last pdu in a
sequence.

On receiving DDP completion cxgbit driver will first
find iSCSI cmd using iscsit_find_cmd_from_itt_or_dump()
then updates cmd->write_data_done, cmd->next_burst_len,
cmd->data_sn and calls  __iscsit_check_dataout_hdr()
to validate iSCSI hdr.

(Move XRDSL check ahead of itt lookup / dump - nab)

Signed-off-by: Varun Prakash <varun@chelsio.com>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
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 b4f1d1cbe521a458c7b7c9c2dd1d3652b2dc7a1b..2285988c209b00ba1f845c8c7afff52ca1fb9825 100644 (file)
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -1431,36 +1431,17 @@ static void iscsit_do_crypto_hash_buf(
 }
 
 int
-iscsit_check_dataout_hdr(struct iscsi_conn *conn, unsigned char *buf,
-                         struct iscsi_cmd **out_cmd)
+__iscsit_check_dataout_hdr(struct iscsi_conn *conn, void *buf,
+                          struct iscsi_cmd *cmd, u32 payload_length,
+                          bool *success)
 {
-       struct iscsi_data *hdr = (struct iscsi_data *)buf;
-       struct iscsi_cmd *cmd = NULL;
+       struct iscsi_data *hdr = buf;
        struct se_cmd *se_cmd;
-       u32 payload_length = ntoh24(hdr->dlength);
        int rc;
 
-       if (!payload_length) {
-               pr_warn("DataOUT payload is ZERO, ignoring.\n");
-               return 0;
-       }
-
        /* iSCSI write */
        atomic_long_add(payload_length, &conn->sess->rx_data_octets);
 
-       if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
-               pr_err("DataSegmentLength: %u is greater than"
-                       " MaxXmitDataSegmentLength: %u\n", payload_length,
-                       conn->conn_ops->MaxXmitDataSegmentLength);
-               return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
-                                        buf);
-       }
-
-       cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt,
-                       payload_length);
-       if (!cmd)
-               return 0;
-
        pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
                " DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
                hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
@@ -1553,10 +1534,44 @@ iscsit_check_dataout_hdr(struct iscsi_conn *conn, unsigned char *buf,
                return 0;
        else if (rc == DATAOUT_CANNOT_RECOVER)
                return -1;
-
-       *out_cmd = cmd;
+       *success = true;
        return 0;
 }
+EXPORT_SYMBOL(__iscsit_check_dataout_hdr);
+
+int
+iscsit_check_dataout_hdr(struct iscsi_conn *conn, void *buf,
+                        struct iscsi_cmd **out_cmd)
+{
+       struct iscsi_data *hdr = buf;
+       struct iscsi_cmd *cmd;
+       u32 payload_length = ntoh24(hdr->dlength);
+       int rc;
+       bool success = false;
+
+       if (!payload_length) {
+               pr_warn_ratelimited("DataOUT payload is ZERO, ignoring.\n");
+               return 0;
+       }
+
+       if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
+               pr_err_ratelimited("DataSegmentLength: %u is greater than"
+                       " MaxXmitDataSegmentLength: %u\n", payload_length,
+                       conn->conn_ops->MaxXmitDataSegmentLength);
+               return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR, buf);
+       }
+
+       cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt, payload_length);
+       if (!cmd)
+               return 0;
+
+       rc = __iscsit_check_dataout_hdr(conn, buf, cmd, payload_length, &success);
+
+       if (success)
+               *out_cmd = cmd;
+
+       return rc;
+}
 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
 
 static int

diff --git a/drivers/target/iscsi/iscsi_target_util.c b/drivers/target/iscsi/iscsi_target_util.c
index b5a1b4ccba124d4dbf60fd528ec05d3a7d0dbf32..f46eadffec0704d4a4d7eaf97a9c8516e0659537 100644 (file)
--- a/drivers/target/iscsi/iscsi_target_util.c
+++ b/drivers/target/iscsi/iscsi_target_util.c
@@ -417,6 +417,7 @@ struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
 
        return NULL;
 }
+EXPORT_SYMBOL(iscsit_find_cmd_from_itt_or_dump);
 
 struct iscsi_cmd *iscsit_find_cmd_from_ttt(
        struct iscsi_conn *conn,

diff --git a/include/target/iscsi/iscsi_transport.h b/include/target/iscsi/iscsi_transport.h
index 1277e9ba031818e22cd8720a4125f1c9ebf0cb12..ff1a4f4cd66d068d9fe74b5b1fc4a63e86a75b81 100644 (file)
--- a/include/target/iscsi/iscsi_transport.h
+++ b/include/target/iscsi/iscsi_transport.h
@@ -55,8 +55,12 @@ extern int iscsit_setup_scsi_cmd(struct iscsi_conn *, struct iscsi_cmd *,
 extern void iscsit_set_unsoliticed_dataout(struct iscsi_cmd *);
 extern int iscsit_process_scsi_cmd(struct iscsi_conn *, struct iscsi_cmd *,
                                struct iscsi_scsi_req *);
-extern int iscsit_check_dataout_hdr(struct iscsi_conn *, unsigned char *,
-                               struct iscsi_cmd **);
+extern int
+__iscsit_check_dataout_hdr(struct iscsi_conn *, void *,
+                          struct iscsi_cmd *, u32, bool *);
+extern int
+iscsit_check_dataout_hdr(struct iscsi_conn *conn, void *buf,
+                        struct iscsi_cmd **out_cmd);
 extern int iscsit_check_dataout_payload(struct iscsi_cmd *, struct iscsi_data *,
                                bool);
 extern int iscsit_setup_nop_out(struct iscsi_conn *, struct iscsi_cmd *,
@@ -125,6 +129,9 @@ extern void iscsit_release_cmd(struct iscsi_cmd *);
 extern void iscsit_free_cmd(struct iscsi_cmd *, bool);
 extern void iscsit_add_cmd_to_immediate_queue(struct iscsi_cmd *,
                                              struct iscsi_conn *, u8);
+extern struct iscsi_cmd *
+iscsit_find_cmd_from_itt_or_dump(struct iscsi_conn *conn,
+                                itt_t init_task_tag, u32 length);
 
 /*
  * From iscsi_target_nego.c