From: Mike Christie <michaelc@xxxxxxxxxxx>
If we sent multiple pdus as immediate the target could be
rejecting some and we have just been dropping the rejection
notification. This adds code to handle nop-out rejections,
so if a nop-out was sent as a ping and rejected we do not
mark the connection bad. Instead we just clean up the timers
since we have pdu making a rount trip we know the connection
is good.
Signed-off-by: Mike Christie <michaelc@xxxxxxxxxxx>
---
drivers/scsi/libiscsi.c | 106 ++++++++++++++++++++++++++++++++++++++--------
1 files changed, 87 insertions(+), 19 deletions(-)
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 3cef35b..957fe25 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -857,27 +857,102 @@ static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
}
}
+static int iscsi_nop_out_rsp(struct iscsi_task *task,
+ struct iscsi_nopin *nop, char *data, int datalen)
+{
+ struct iscsi_conn *conn = task->conn;
+ int rc = 0;
+
+ if (conn->ping_task != task) {
+ /*
+ * If this is not in response to one of our
+ * nops then it must be from userspace.
+ */
+ if (iscsi_recv_pdu(conn->cls_conn, (struct iscsi_hdr *)nop,
+ data, datalen))
+ rc = ISCSI_ERR_CONN_FAILED;
+ } else
+ mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
+ iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
+ return rc;
+}
+
static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
char *data, int datalen)
{
struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
struct iscsi_hdr rejected_pdu;
+ int opcode, rc = 0;
conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
- if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
- if (ntoh24(reject->dlength) > datalen)
- return ISCSI_ERR_PROTO;
+ if (ntoh24(reject->dlength) > datalen ||
+ ntoh24(reject->dlength) < sizeof(struct iscsi_hdr)) {
+ iscsi_conn_printk(KERN_ERR, conn, "Cannot handle rejected "
+ "pdu. Invalid data length (pdu dlength "
+ "%u, datalen %d\n", ntoh24(reject->dlength),
+ datalen);
+ return ISCSI_ERR_PROTO;
+ }
+ memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
+ opcode = rejected_pdu.opcode & ISCSI_OPCODE_MASK;
- if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
- memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
- iscsi_conn_printk(KERN_ERR, conn,
- "pdu (op 0x%x) rejected "
- "due to DataDigest error.\n",
- rejected_pdu.opcode);
+ switch (reject->reason) {
+ case ISCSI_REASON_DATA_DIGEST_ERROR:
+ iscsi_conn_printk(KERN_ERR, conn,
+ "pdu (op 0x%x itt 0x%x) rejected "
+ "due to DataDigest error.\n",
+ rejected_pdu.itt, opcode);
+ break;
+ case ISCSI_REASON_IMM_CMD_REJECT:
+ iscsi_conn_printk(KERN_ERR, conn,
+ "pdu (op 0x%x itt 0x%x) rejected. Too many "
+ "immediate commands.\n",
+ rejected_pdu.itt, opcode);
+ /*
+ * We only send one TMF at a time so if the target could not
+ * handle it, then it should get fixed (RFC mandates that
+ * a target can handle one immediate TMF per conn).
+ *
+ * For nops-outs, we could have sent more than one if
+ * the target is sending us lots of nop-ins
+ */
+ if (opcode != ISCSI_OP_NOOP_OUT)
+ return 0;
+
+ if (rejected_pdu.itt == cpu_to_be32(ISCSI_RESERVED_TAG))
+ /*
+ * nop-out in response to target's nop-out rejected.
+ * Just resend.
+ */
+ iscsi_send_nopout(conn,
+ (struct iscsi_nopin*)&rejected_pdu);
+ else {
+ struct iscsi_task *task;
+ /*
+ * Our nop as ping got dropped. We know the target
+ * and transport are ok so just clean up
+ */
+ task = iscsi_itt_to_task(conn, rejected_pdu.itt);
+ if (!task) {
+ iscsi_conn_printk(KERN_ERR, conn,
+ "Invalid pdu reject. Could "
+ "not lookup rejected task.\n");
+ rc = ISCSI_ERR_BAD_ITT;
+ } else
+ rc = iscsi_nop_out_rsp(task,
+ (struct iscsi_nopin*)&rejected_pdu,
+ NULL, 0);
}
+ break;
+ default:
+ iscsi_conn_printk(KERN_ERR, conn,
+ "pdu (op 0x%x itt 0x%x) rejected. Reason "
+ "code 0x%x\n", rejected_pdu.itt,
+ rejected_pdu.opcode, reject->reason);
+ break;
}
- return 0;
+ return rc;
}
/**
@@ -1038,15 +1113,8 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
}
conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
- if (conn->ping_task != task)
- /*
- * If this is not in response to one of our
- * nops then it must be from userspace.
- */
- goto recv_pdu;
-
- mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
- iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
+ rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)hdr,
+ data, datalen);
break;
default:
rc = ISCSI_ERR_BAD_OPCODE;
--
1.6.2.2
--
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