Commit 7a89f9c6 authored by Chuck Lever's avatar Chuck Lever Committed by Anna Schumaker
Browse files

xprtrdma: Honor ->send_request API contract 



Commit c93c6223 ("xprtrdma: Disconnect on registration failure")
added a disconnect for some RPC marshaling failures. This is needed
only in a handful of cases, but it was triggering for simple stuff
like temporary resource shortages. Try to straighten this out.

Fix up the lower layers so they don't return -ENOMEM or other error
codes that the RPC client's FSM doesn't explicitly recognize.

Also fix up the places in the send_request path that do want a
disconnect. For example, when ib_post_send or ib_post_recv fail,
this is a sign that there is a send or receive queue resource
miscalculation. That should be rare, and is a sign of a software
bug. But xprtrdma can recover: disconnect to reset the transport and
start over.

Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
Tested-by: default avatarSteve Wise <swise@opengridcomputing.com>
Signed-off-by: default avatarAnna Schumaker <Anna.Schumaker@Netapp.com>
parent 3d4cf35b

net/sunrpc/xprtrdma/fmr_ops.c

+3 −3
Original line number Diff line number Diff line
@@ -219,7 +219,7 @@ fmr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg, 
		rpcrdma_defer_mr_recovery(mw);

	mw = rpcrdma_get_mw(r_xprt);

	if (!mw)

		return -ENOMEM;

		return -ENOBUFS;



	pageoff = offset_in_page(seg1->mr_offset);

	seg1->mr_offset -= pageoff;	/* start of page */
@@ -269,14 +269,14 @@ out_dmamap_err: 
	pr_err("rpcrdma: failed to dma map sg %p sg_nents %u\n",

	       mw->mw_sg, mw->mw_nents);

	rpcrdma_defer_mr_recovery(mw);

	return -ENOMEM;

	return -EIO;



out_maperr:

	pr_err("rpcrdma: ib_map_phys_fmr %u@0x%llx+%i (%d) status %i\n",

	       len, (unsigned long long)dma_pages[0],

	       pageoff, mw->mw_nents, rc);

	rpcrdma_defer_mr_recovery(mw);

	return rc;

	return -EIO;

}



/* Invalidate all memory regions that were registered for "req".

net/sunrpc/xprtrdma/frwr_ops.c

+7 −6
Original line number Diff line number Diff line
@@ -382,7 +382,7 @@ frwr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg, 
			rpcrdma_defer_mr_recovery(mw);

		mw = rpcrdma_get_mw(r_xprt);

		if (!mw)

			return -ENOMEM;

			return -ENOBUFS;

	} while (mw->frmr.fr_state != FRMR_IS_INVALID);

	frmr = &mw->frmr;

	frmr->fr_state = FRMR_IS_VALID;
@@ -456,18 +456,18 @@ out_dmamap_err: 
	pr_err("rpcrdma: failed to dma map sg %p sg_nents %u\n",

	       mw->mw_sg, mw->mw_nents);

	rpcrdma_defer_mr_recovery(mw);

	return -ENOMEM;

	return -EIO;



out_mapmr_err:

	pr_err("rpcrdma: failed to map mr %p (%u/%u)\n",

	       frmr->fr_mr, n, mw->mw_nents);

	rc = n < 0 ? n : -EIO;

	rpcrdma_defer_mr_recovery(mw);

	return rc;

	return -EIO;



out_senderr:

	pr_err("rpcrdma: FRMR registration ib_post_send returned %i\n", rc);

	rpcrdma_defer_mr_recovery(mw);

	return rc;

	return -ENOTCONN;

}



static struct ib_send_wr *
@@ -569,7 +569,8 @@ unmap: 
	return;



reset_mrs:

	pr_warn("%s: ib_post_send failed %i\n", __func__, rc);

	pr_err("rpcrdma: FRMR invalidate ib_post_send returned %i\n", rc);

	rdma_disconnect(ia->ri_id);



	/* Find and reset the MRs in the LOCAL_INV WRs that did not

	 * get posted. This is synchronous, and slow.

net/sunrpc/xprtrdma/rpc_rdma.c

+1 −1
Original line number Diff line number Diff line
@@ -251,7 +251,7 @@ rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, unsigned int pos, 
			/* alloc the pagelist for receiving buffer */

			ppages[p] = alloc_page(GFP_ATOMIC);

			if (!ppages[p])

				return -ENOMEM;

				return -EAGAIN;

		}

		seg[n].mr_page = ppages[p];

		seg[n].mr_offset = (void *)(unsigned long) page_base;

net/sunrpc/xprtrdma/transport.c

+15 −5
Original line number Diff line number Diff line
@@ -558,7 +558,6 @@ out_sendbuf: 


out_fail:

	rpcrdma_buffer_put(req);

	r_xprt->rx_stats.failed_marshal_count++;

	return NULL;

}
@@ -590,8 +589,19 @@ xprt_rdma_free(void *buffer) 
	rpcrdma_buffer_put(req);

}



/*

/**

 * xprt_rdma_send_request - marshal and send an RPC request

 * @task: RPC task with an RPC message in rq_snd_buf

 *

 * Return values:

 *        0:	The request has been sent

 * ENOTCONN:	Caller needs to invoke connect logic then call again

 *  ENOBUFS:	Call again later to send the request

 *      EIO:	A permanent error occurred. The request was not sent,

 *		and don't try it again

 *

 * send_request invokes the meat of RPC RDMA. It must do the following:

 *

 *  1.  Marshal the RPC request into an RPC RDMA request, which means

 *	putting a header in front of data, and creating IOVs for RDMA

 *	from those in the request.
@@ -600,7 +610,6 @@ xprt_rdma_free(void *buffer) 
 *	the request (rpcrdma_ep_post).

 *  4.  No partial sends are possible in the RPC-RDMA protocol (as in UDP).

 */



static int

xprt_rdma_send_request(struct rpc_task *task)

{
@@ -630,11 +639,12 @@ xprt_rdma_send_request(struct rpc_task *task) 
	return 0;



failed_marshal:

	r_xprt->rx_stats.failed_marshal_count++;

	dprintk("RPC:       %s: rpcrdma_marshal_req failed, status %i\n",

		__func__, rc);

	if (rc == -EIO)

		return -EIO;

		r_xprt->rx_stats.failed_marshal_count++;

	if (rc != -ENOTCONN)

		return rc;

drop_connection:

	xprt_disconnect_done(xprt);

	return -ENOTCONN;	/* implies disconnect */

net/sunrpc/xprtrdma/verbs.c

+13 −9
Original line number Diff line number Diff line
@@ -1151,7 +1151,7 @@ rpcrdma_ep_post(struct rpcrdma_ia *ia, 
	if (rep) {

		rc = rpcrdma_ep_post_recv(ia, ep, rep);

		if (rc)

			goto out;

			return rc;

		req->rl_reply = NULL;

	}
@@ -1176,10 +1176,12 @@ rpcrdma_ep_post(struct rpcrdma_ia *ia, 


	rc = ib_post_send(ia->ri_id->qp, &send_wr, &send_wr_fail);

	if (rc)

		dprintk("RPC:       %s: ib_post_send returned %i\n", __func__,

			rc);

out:

	return rc;

		goto out_postsend_err;

	return 0;



out_postsend_err:

	pr_err("rpcrdma: RDMA Send ib_post_send returned %i\n", rc);

	return -ENOTCONN;

}



/*
@@ -1204,11 +1206,13 @@ rpcrdma_ep_post_recv(struct rpcrdma_ia *ia, 
				   DMA_BIDIRECTIONAL);



	rc = ib_post_recv(ia->ri_id->qp, &recv_wr, &recv_wr_fail);



	if (rc)

		dprintk("RPC:       %s: ib_post_recv returned %i\n", __func__,

			rc);

	return rc;

		goto out_postrecv;

	return 0;



out_postrecv:

	pr_err("rpcrdma: ib_post_recv returned %i\n", rc);

	return -ENOTCONN;

}



/**

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