Commit 18d065a5 authored by Chuck Lever's avatar Chuck Lever Committed by Anna Schumaker
Browse files

xprtrdma: Eliminate per-transport "max pages" 



To support device hotplug and migrating a connection between devices
of different capabilities, we have to guarantee that all in-kernel
devices can support the same max NFS payload size (1 megabyte).

This means that possibly one or two in-tree devices are no longer
supported for NFS/RDMA because they cannot support 1MB rsize/wsize.
The only one I confirmed was cxgb3, but it has already been removed
from the kernel.

Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
Signed-off-by: default avatarAnna Schumaker <Anna.Schumaker@Netapp.com>
parent 7581d901

net/sunrpc/xprtrdma/frwr_ops.c

+15 −25
Original line number Diff line number Diff line
@@ -178,7 +178,7 @@ out_list_err: 
 *	ep->rep_attr.cap.max_send_wr

 *	ep->rep_attr.cap.max_recv_wr

 *	ep->rep_max_requests

 *	ia->ri_max_segs

 *	ia->ri_max_rdma_segs

 *

 * And these FRWR-related fields:

 *	ia->ri_max_frwr_depth
@@ -209,14 +209,12 @@ int frwr_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep) 
	 * capability, but perform optimally when the MRs are not larger

	 * than a page.

	 */

	if (attrs->max_sge_rd > 1)

	if (attrs->max_sge_rd > RPCRDMA_MAX_HDR_SEGS)

		ia->ri_max_frwr_depth = attrs->max_sge_rd;

	else

		ia->ri_max_frwr_depth = attrs->max_fast_reg_page_list_len;

	if (ia->ri_max_frwr_depth > RPCRDMA_MAX_DATA_SEGS)

		ia->ri_max_frwr_depth = RPCRDMA_MAX_DATA_SEGS;

	dprintk("RPC:       %s: max FR page list depth = %u\n",

		__func__, ia->ri_max_frwr_depth);



	/* Add room for frwr register and invalidate WRs.

	 * 1. FRWR reg WR for head
@@ -260,30 +258,22 @@ int frwr_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep) 
	ep->rep_attr.cap.max_recv_wr += RPCRDMA_BACKWARD_WRS;

	ep->rep_attr.cap.max_recv_wr += 1; /* for ib_drain_rq */



	ia->ri_max_segs =

	ia->ri_max_rdma_segs =

		DIV_ROUND_UP(RPCRDMA_MAX_DATA_SEGS, ia->ri_max_frwr_depth);

	/* Reply chunks require segments for head and tail buffers */

	ia->ri_max_segs += 2;

	if (ia->ri_max_segs > RPCRDMA_MAX_HDR_SEGS)

		ia->ri_max_segs = RPCRDMA_MAX_HDR_SEGS;

	return 0;

}

	ia->ri_max_rdma_segs += 2;

	if (ia->ri_max_rdma_segs > RPCRDMA_MAX_HDR_SEGS)

		ia->ri_max_rdma_segs = RPCRDMA_MAX_HDR_SEGS;



/**

 * frwr_maxpages - Compute size of largest payload

 * @r_xprt: transport

 *

 * Returns maximum size of an RPC message, in pages.

 *

 * FRWR mode conveys a list of pages per chunk segment. The

 * maximum length of that list is the FRWR page list depth.

	/* Ensure the underlying device is capable of conveying the

	 * largest r/wsize NFS will ask for. This guarantees that

	 * failing over from one RDMA device to another will not

	 * break NFS I/O.

	 */

size_t frwr_maxpages(struct rpcrdma_xprt *r_xprt)

{

	struct rpcrdma_ia *ia = &r_xprt->rx_ia;

	if ((ia->ri_max_rdma_segs * ia->ri_max_frwr_depth) < RPCRDMA_MAX_SEGS)

		return -ENOMEM;



	return min_t(unsigned int, RPCRDMA_MAX_DATA_SEGS,

		     (ia->ri_max_segs - 2) * ia->ri_max_frwr_depth);

	return 0;

}



/**

net/sunrpc/xprtrdma/rpc_rdma.c

+1 −1
Original line number Diff line number Diff line
@@ -111,7 +111,7 @@ static unsigned int rpcrdma_max_reply_header_size(unsigned int maxsegs) 
 */

void rpcrdma_set_max_header_sizes(struct rpcrdma_xprt *r_xprt)

{

	unsigned int maxsegs = r_xprt->rx_ia.ri_max_segs;

	unsigned int maxsegs = r_xprt->rx_ia.ri_max_rdma_segs;

	struct rpcrdma_ep *ep = &r_xprt->rx_ep;



	ep->rep_max_inline_send =

net/sunrpc/xprtrdma/transport.c

+4 −10
Original line number Diff line number Diff line
@@ -359,19 +359,13 @@ xprt_setup_rdma(struct xprt_create *args) 
	if (rc)

		goto out3;



	INIT_DELAYED_WORK(&new_xprt->rx_connect_worker,

			  xprt_rdma_connect_worker);



	xprt->max_payload = frwr_maxpages(new_xprt);

	if (xprt->max_payload == 0)

		goto out4;

	xprt->max_payload <<= PAGE_SHIFT;

	dprintk("RPC:       %s: transport data payload maximum: %zu bytes\n",

		__func__, xprt->max_payload);



	if (!try_module_get(THIS_MODULE))

		goto out4;



	INIT_DELAYED_WORK(&new_xprt->rx_connect_worker,

			  xprt_rdma_connect_worker);

	xprt->max_payload = RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT;



	dprintk("RPC:       %s: %s:%s\n", __func__,

		xprt->address_strings[RPC_DISPLAY_ADDR],

		xprt->address_strings[RPC_DISPLAY_PORT]);

net/sunrpc/xprtrdma/verbs.c

+2 −2
Original line number Diff line number Diff line
@@ -936,7 +936,7 @@ rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt) 
	struct rpcrdma_ia *ia = &r_xprt->rx_ia;

	unsigned int count;



	for (count = 0; count < ia->ri_max_segs; count++) {

	for (count = 0; count < ia->ri_max_rdma_segs; count++) {

		struct rpcrdma_mr *mr;

		int rc;
@@ -1018,7 +1018,7 @@ struct rpcrdma_req *rpcrdma_req_create(struct rpcrdma_xprt *r_xprt, size_t size, 


	/* Compute maximum header buffer size in bytes */

	maxhdrsize = rpcrdma_fixed_maxsz + 3 +

		     r_xprt->rx_ia.ri_max_segs * rpcrdma_readchunk_maxsz;

		     r_xprt->rx_ia.ri_max_rdma_segs * rpcrdma_readchunk_maxsz;

	maxhdrsize *= sizeof(__be32);

	rb = rpcrdma_regbuf_alloc(__roundup_pow_of_two(maxhdrsize),

				  DMA_TO_DEVICE, flags);

net/sunrpc/xprtrdma/xprt_rdma.h

+1 −2
Original line number Diff line number Diff line
@@ -71,7 +71,7 @@ struct rpcrdma_ia { 
	struct rdma_cm_id 	*ri_id;

	struct ib_pd		*ri_pd;

	int			ri_async_rc;

	unsigned int		ri_max_segs;

	unsigned int		ri_max_rdma_segs;

	unsigned int		ri_max_frwr_depth;

	bool			ri_implicit_roundup;

	enum ib_mr_type		ri_mrtype;
@@ -539,7 +539,6 @@ void frwr_reset(struct rpcrdma_req *req); 
int frwr_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep);

int frwr_init_mr(struct rpcrdma_ia *ia, struct rpcrdma_mr *mr);

void frwr_release_mr(struct rpcrdma_mr *mr);

size_t frwr_maxpages(struct rpcrdma_xprt *r_xprt);

struct rpcrdma_mr_seg *frwr_map(struct rpcrdma_xprt *r_xprt,

				struct rpcrdma_mr_seg *seg,

				int nsegs, bool writing, __be32 xid,

CRA Git | Maintained and supported by SUSTech CRA and CCSE