Commit d5cf9030 authored by Daniel Verkamp's avatar Daniel Verkamp
Browse files

nvmf: remove nvmf_recv() SQ overflow handling 



The overflow condition can't happen unless there is a programming error
in the nvmf_tgt library; we can only possibly receive command capsules
(sq entries from the point of view of the host) if we have posted a RDMA
Recv for the command capsule memory region.

This means that we also don't need to track sq_tail in the NVMf library.

Change-Id: I101509080c744528871e72fa46d188e2850c928a
Signed-off-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
parent d9709895

lib/nvmf/conn.c

+1 −44
Original line number Diff line number Diff line
@@ -177,7 +177,7 @@ spdk_nvmf_allocate_conn(void) 
	conn->sess = NULL;



	conn->state = CONN_STATE_INVALID;

	conn->sq_head = conn->sq_tail = 0;

	conn->sq_head = 0;



	return conn;
@@ -436,42 +436,6 @@ static int nvmf_recv(struct spdk_nvmf_conn *conn, struct ibv_wc *wc) 
	rx_desc = (struct nvme_qp_rx_desc *)wc->wr_id;

	cap_hdr = &rx_desc->cmd.nvmf_cmd;



	/* Update Connection SQ Tracking, increment

	   the SQ tail consuming a free RX recv slot.

	   Check for exceeding queue full - should

	   never happen.

	*/

	conn->sq_tail < (conn->sq_depth - 1) ? (conn->sq_tail++) : (conn->sq_tail = 0);

	SPDK_TRACELOG(SPDK_TRACE_DEBUG, "sq_head %x, sq_tail %x, sq_depth %x\n",

		      conn->sq_head, conn->sq_tail, conn->sq_depth);

	/* trap if initiator exceeds qdepth */

	if (conn->sq_head == conn->sq_tail) {

		SPDK_ERRLOG("	*** SQ Overflow !! ***\n");

		/* controller fatal status condition:

		   set the cfs flag in controller status

		   and stop processing this and any I/O

		   on this queue.

		*/

		if (conn->sess) {

			conn->sess->vcprop.csts.bits.cfs = 1;

			conn->state = CONN_STATE_OVERFLOW;

		}

		if (conn->type == CONN_TYPE_IOQ) {

			/* if overflow on the I/O queue

			   stop processing, allow for

			   remote host to query failure

			   via admin queue

			 */

			return 0;

		} else {

			/* if overflow on the admin queue

			   there is no recovery, error out

			   to trigger disconnect

			 */

			return -1;

		}

	}



	if (wc->byte_len < sizeof(*cap_hdr)) {

		SPDK_ERRLOG("recv length less than capsule header\n");

		return -1;
@@ -534,13 +498,6 @@ static int nvmf_check_rdma_completions(struct spdk_nvmf_conn *conn) 
	for (i = 0; i < conn->sq_depth; i++) {

		tx_desc = NULL;



		/* if an overflow condition was hit

		   we want to stop all processing, but

		   do not disconnect.

		 */

		if (conn->state == CONN_STATE_OVERFLOW)

			break;



		rc = ibv_poll_cq(conn->rdma.cq, 1, &wc);

		if (rc == 0) // No completions at this time

			break;

lib/nvmf/conn.h

+0 −2
Original line number Diff line number Diff line
@@ -46,7 +46,6 @@ enum conn_state { 
	CONN_STATE_INVALID = 0,

	CONN_STATE_RUNNING = 1,

	CONN_STATE_FABRIC_DISCONNECT = 2,

	CONN_STATE_OVERFLOW = 3,

	CONN_STATE_EXITING = 4,

};
@@ -75,7 +74,6 @@ struct spdk_nvmf_conn { 
	volatile enum conn_state	state;



	uint16_t			sq_head;

	uint16_t			sq_tail;



	struct spdk_nvmf_rdma_conn	rdma;