net/sunrpc/xprtrdma/fmr_ops.c - kernel/quantenna - Git at Google

 /*
  * Copyright (c) 2015 Oracle.  All rights reserved.
  * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
  */

 /* Lightweight memory registration using Fast Memory Regions (FMR).
  * Referred to sometimes as MTHCAFMR mode.
  *
  * FMR uses synchronous memory registration and deregistration.
  * FMR registration is known to be fast, but FMR deregistration
  * can take tens of usecs to complete.
  */

 /* Normal operation
  *
  * A Memory Region is prepared for RDMA READ or WRITE using the
  * ib_map_phys_fmr verb (fmr_op_map). When the RDMA operation is
  * finished, the Memory Region is unmapped using the ib_unmap_fmr
  * verb (fmr_op_unmap).
  */

 /* Transport recovery
  *
  * After a transport reconnect, fmr_op_map re-uses the MR already
  * allocated for the RPC, but generates a fresh rkey then maps the
  * MR again. This process is synchronous.
  */

 #include "xprt_rdma.h"

 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 # define RPCDBG_FACILITY	RPCDBG_TRANS
 #endif

 /* Maximum scatter/gather per FMR */
 #define RPCRDMA_MAX_FMR_SGES	(64)

 static struct workqueue_struct *fmr_recovery_wq;

 #define FMR_RECOVERY_WQ_FLAGS		(WQ_UNBOUND)

 int
 fmr_alloc_recovery_wq(void)
 {
 	fmr_recovery_wq = alloc_workqueue("fmr_recovery", WQ_UNBOUND, 0);
 	return !fmr_recovery_wq ? -ENOMEM : 0;
 }

 void
 fmr_destroy_recovery_wq(void)
 {
 	struct workqueue_struct *wq;

 	if (!fmr_recovery_wq)
 		return;

 	wq = fmr_recovery_wq;
 	fmr_recovery_wq = NULL;
 	destroy_workqueue(wq);
 }

 static int
 __fmr_unmap(struct rpcrdma_mw *mw)
 {
 	LIST_HEAD(l);

 	list_add(&mw->fmr.fmr->list, &l);
 	return ib_unmap_fmr(&l);
 }

 /* Deferred reset of a single FMR. Generate a fresh rkey by
  * replacing the MR. There's no recovery if this fails.
  */
 static void
 __fmr_recovery_worker(struct work_struct *work)
 {
 	struct rpcrdma_mw *mw = container_of(work, struct rpcrdma_mw,
 					    mw_work);
 	struct rpcrdma_xprt *r_xprt = mw->mw_xprt;

 	__fmr_unmap(mw);
 	rpcrdma_put_mw(r_xprt, mw);
 	return;
 }

 /* A broken MR was discovered in a context that can't sleep.
  * Defer recovery to the recovery worker.
  */
 static void
 __fmr_queue_recovery(struct rpcrdma_mw *mw)
 {
 	INIT_WORK(&mw->mw_work, __fmr_recovery_worker);
 	queue_work(fmr_recovery_wq, &mw->mw_work);
 }

 static int
 fmr_op_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep,
 	    struct rpcrdma_create_data_internal *cdata)
 {
 	rpcrdma_set_max_header_sizes(ia, cdata, max_t(unsigned int, 1,
 						      RPCRDMA_MAX_DATA_SEGS /
 						      RPCRDMA_MAX_FMR_SGES));
 	return 0;
 }

 /* FMR mode conveys up to 64 pages of payload per chunk segment.
  */
 static size_t
 fmr_op_maxpages(struct rpcrdma_xprt *r_xprt)
 {
 	return min_t(unsigned int, RPCRDMA_MAX_DATA_SEGS,
 		     RPCRDMA_MAX_HDR_SEGS * RPCRDMA_MAX_FMR_SGES);
 }

 static int
 fmr_op_init(struct rpcrdma_xprt *r_xprt)
 {
 	struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
 	int mr_access_flags = IB_ACCESS_REMOTE_WRITE | IB_ACCESS_REMOTE_READ;
 	struct ib_fmr_attr fmr_attr = {
 		.max_pages	= RPCRDMA_MAX_FMR_SGES,
 		.max_maps	= 1,
 		.page_shift	= PAGE_SHIFT
 	};
 	struct ib_pd *pd = r_xprt->rx_ia.ri_pd;
 	struct rpcrdma_mw *r;
 	int i, rc;

 	spin_lock_init(&buf->rb_mwlock);
 	INIT_LIST_HEAD(&buf->rb_mws);
 	INIT_LIST_HEAD(&buf->rb_all);

 	i = max_t(int, RPCRDMA_MAX_DATA_SEGS / RPCRDMA_MAX_FMR_SGES, 1);
 	i += 2;				/* head + tail */
 	i *= buf->rb_max_requests;	/* one set for each RPC slot */
 	dprintk("RPC:       %s: initalizing %d FMRs\n", __func__, i);

 	rc = -ENOMEM;
 	while (i--) {
 		r = kzalloc(sizeof(*r), GFP_KERNEL);
 		if (!r)
 			goto out;

 		r->fmr.physaddrs = kmalloc(RPCRDMA_MAX_FMR_SGES *
 					   sizeof(u64), GFP_KERNEL);
 		if (!r->fmr.physaddrs)
 			goto out_free;

 		r->fmr.fmr = ib_alloc_fmr(pd, mr_access_flags, &fmr_attr);
 		if (IS_ERR(r->fmr.fmr))
 			goto out_fmr_err;

 		r->mw_xprt = r_xprt;
 		list_add(&r->mw_list, &buf->rb_mws);
 		list_add(&r->mw_all, &buf->rb_all);
 	}
 	return 0;

 out_fmr_err:
 	rc = PTR_ERR(r->fmr.fmr);
 	dprintk("RPC:       %s: ib_alloc_fmr status %i\n", __func__, rc);
 	kfree(r->fmr.physaddrs);
 out_free:
 	kfree(r);
 out:
 	return rc;
 }

 /* Use the ib_map_phys_fmr() verb to register a memory region
  * for remote access via RDMA READ or RDMA WRITE.
  */
 static int
 fmr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,
 	   int nsegs, bool writing)
 {
 	struct rpcrdma_ia *ia = &r_xprt->rx_ia;
 	struct ib_device *device = ia->ri_device;
 	enum dma_data_direction direction = rpcrdma_data_dir(writing);
 	struct rpcrdma_mr_seg *seg1 = seg;
 	int len, pageoff, i, rc;
 	struct rpcrdma_mw *mw;

 	mw = seg1->rl_mw;
 	seg1->rl_mw = NULL;
 	if (!mw) {
 		mw = rpcrdma_get_mw(r_xprt);
 		if (!mw)
 			return -ENOMEM;
 	} else {
 		/* this is a retransmit; generate a fresh rkey */
 		rc = __fmr_unmap(mw);
 		if (rc)
 			return rc;
 	}

 	pageoff = offset_in_page(seg1->mr_offset);
 	seg1->mr_offset -= pageoff;	/* start of page */
 	seg1->mr_len += pageoff;
 	len = -pageoff;
 	if (nsegs > RPCRDMA_MAX_FMR_SGES)
 		nsegs = RPCRDMA_MAX_FMR_SGES;
 	for (i = 0; i < nsegs;) {
 		rpcrdma_map_one(device, seg, direction);
 		mw->fmr.physaddrs[i] = seg->mr_dma;
 		len += seg->mr_len;
 		++seg;
 		++i;
 		/* Check for holes */
 		if ((i < nsegs && offset_in_page(seg->mr_offset)) ||
 		    offset_in_page((seg-1)->mr_offset + (seg-1)->mr_len))
 			break;
 	}

 	rc = ib_map_phys_fmr(mw->fmr.fmr, mw->fmr.physaddrs,
 			     i, seg1->mr_dma);
 	if (rc)
 		goto out_maperr;

 	seg1->rl_mw = mw;
 	seg1->mr_rkey = mw->fmr.fmr->rkey;
 	seg1->mr_base = seg1->mr_dma + pageoff;
 	seg1->mr_nsegs = i;
 	seg1->mr_len = len;
 	return i;

 out_maperr:
 	dprintk("RPC:       %s: ib_map_phys_fmr %u@0x%llx+%i (%d) status %i\n",
 		__func__, len, (unsigned long long)seg1->mr_dma,
 		pageoff, i, rc);
 	while (i--)
 		rpcrdma_unmap_one(device, --seg);
 	return rc;
 }

 static void
 __fmr_dma_unmap(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg)
 {
 	struct ib_device *device = r_xprt->rx_ia.ri_device;
 	int nsegs = seg->mr_nsegs;

 	while (nsegs--)
 		rpcrdma_unmap_one(device, seg++);
 }

 /* Invalidate all memory regions that were registered for "req".
  *
  * Sleeps until it is safe for the host CPU to access the
  * previously mapped memory regions.
  */
 static void
 fmr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
 {
 	struct rpcrdma_mr_seg *seg;
 	unsigned int i, nchunks;
 	struct rpcrdma_mw *mw;
 	LIST_HEAD(unmap_list);
 	int rc;

 	dprintk("RPC:       %s: req %p\n", __func__, req);

 	/* ORDER: Invalidate all of the req's MRs first
 	 *
 	 * ib_unmap_fmr() is slow, so use a single call instead
 	 * of one call per mapped MR.
 	 */
 	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {
 		seg = &req->rl_segments[i];
 		mw = seg->rl_mw;

 		list_add(&mw->fmr.fmr->list, &unmap_list);

 		i += seg->mr_nsegs;
 	}
 	rc = ib_unmap_fmr(&unmap_list);
 	if (rc)
 		pr_warn("%s: ib_unmap_fmr failed (%i)\n", __func__, rc);

 	/* ORDER: Now DMA unmap all of the req's MRs, and return
 	 * them to the free MW list.
 	 */
 	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {
 		seg = &req->rl_segments[i];

 		__fmr_dma_unmap(r_xprt, seg);
 		rpcrdma_put_mw(r_xprt, seg->rl_mw);

 		i += seg->mr_nsegs;
 		seg->mr_nsegs = 0;
 		seg->rl_mw = NULL;
 	}

 	req->rl_nchunks = 0;
 }

 /* Use a slow, safe mechanism to invalidate all memory regions
  * that were registered for "req".
  *
  * In the asynchronous case, DMA unmapping occurs first here
  * because the rpcrdma_mr_seg is released immediately after this
  * call. It's contents won't be available in __fmr_dma_unmap later.
  * FIXME.
  */
 static void
 fmr_op_unmap_safe(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req,
 		  bool sync)
 {
 	struct rpcrdma_mr_seg *seg;
 	struct rpcrdma_mw *mw;
 	unsigned int i;

 	for (i = 0; req->rl_nchunks; req->rl_nchunks--) {
 		seg = &req->rl_segments[i];
 		mw = seg->rl_mw;

 		if (sync) {
 			/* ORDER */
 			__fmr_unmap(mw);
 			__fmr_dma_unmap(r_xprt, seg);
 			rpcrdma_put_mw(r_xprt, mw);
 		} else {
 			__fmr_dma_unmap(r_xprt, seg);
 			__fmr_queue_recovery(mw);
 		}

 		i += seg->mr_nsegs;
 		seg->mr_nsegs = 0;
 		seg->rl_mw = NULL;
 	}
 }

 static void
 fmr_op_destroy(struct rpcrdma_buffer *buf)
 {
 	struct rpcrdma_mw *r;
 	int rc;

 	while (!list_empty(&buf->rb_all)) {
 		r = list_entry(buf->rb_all.next, struct rpcrdma_mw, mw_all);
 		list_del(&r->mw_all);
 		kfree(r->fmr.physaddrs);

 		rc = ib_dealloc_fmr(r->fmr.fmr);
 		if (rc)
 			dprintk("RPC:       %s: ib_dealloc_fmr failed %i\n",
 				__func__, rc);

 		kfree(r);
 	}
 }

 const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops = {
 	.ro_map				= fmr_op_map,
 	.ro_unmap_sync			= fmr_op_unmap_sync,
 	.ro_unmap_safe			= fmr_op_unmap_safe,
 	.ro_open			= fmr_op_open,
 	.ro_maxpages			= fmr_op_maxpages,
 	.ro_init			= fmr_op_init,
 	.ro_destroy			= fmr_op_destroy,
 	.ro_displayname			= "fmr",
 };
	/*
	* Copyright (c) 2015 Oracle. All rights reserved.
	* Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
	*/

	/* Lightweight memory registration using Fast Memory Regions (FMR).
	* Referred to sometimes as MTHCAFMR mode.
	*
	* FMR uses synchronous memory registration and deregistration.
	* FMR registration is known to be fast, but FMR deregistration
	* can take tens of usecs to complete.
	*/

	/* Normal operation
	*
	* A Memory Region is prepared for RDMA READ or WRITE using the
	* ib_map_phys_fmr verb (fmr_op_map). When the RDMA operation is
	* finished, the Memory Region is unmapped using the ib_unmap_fmr
	* verb (fmr_op_unmap).
	*/

	/* Transport recovery
	*
	* After a transport reconnect, fmr_op_map re-uses the MR already
	* allocated for the RPC, but generates a fresh rkey then maps the
	* MR again. This process is synchronous.
	*/

	#include "xprt_rdma.h"

	#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
	# define RPCDBG_FACILITY RPCDBG_TRANS
	#endif

	/* Maximum scatter/gather per FMR */
	#define RPCRDMA_MAX_FMR_SGES (64)

	static struct workqueue_struct *fmr_recovery_wq;

	#define FMR_RECOVERY_WQ_FLAGS (WQ_UNBOUND)

	int
	fmr_alloc_recovery_wq(void)
	{
	fmr_recovery_wq = alloc_workqueue("fmr_recovery", WQ_UNBOUND, 0);
	return !fmr_recovery_wq ? -ENOMEM : 0;
	}

	void
	fmr_destroy_recovery_wq(void)
	{
	struct workqueue_struct *wq;

	if (!fmr_recovery_wq)
	return;

	wq = fmr_recovery_wq;
	fmr_recovery_wq = NULL;
	destroy_workqueue(wq);
	}

	static int
	__fmr_unmap(struct rpcrdma_mw *mw)
	{
	LIST_HEAD(l);

	list_add(&mw->fmr.fmr->list, &l);
	return ib_unmap_fmr(&l);
	}

	/* Deferred reset of a single FMR. Generate a fresh rkey by
	* replacing the MR. There's no recovery if this fails.
	*/
	static void
	__fmr_recovery_worker(struct work_struct *work)
	{
	struct rpcrdma_mw *mw = container_of(work, struct rpcrdma_mw,
	mw_work);
	struct rpcrdma_xprt *r_xprt = mw->mw_xprt;

	__fmr_unmap(mw);
	rpcrdma_put_mw(r_xprt, mw);
	return;
	}

	/* A broken MR was discovered in a context that can't sleep.
	* Defer recovery to the recovery worker.
	*/
	static void
	__fmr_queue_recovery(struct rpcrdma_mw *mw)
	{
	INIT_WORK(&mw->mw_work, __fmr_recovery_worker);
	queue_work(fmr_recovery_wq, &mw->mw_work);
	}

	static int
	fmr_op_open(struct rpcrdma_ia ia, struct rpcrdma_ep ep,
	struct rpcrdma_create_data_internal *cdata)
	{
	rpcrdma_set_max_header_sizes(ia, cdata, max_t(unsigned int, 1,
	RPCRDMA_MAX_DATA_SEGS /
	RPCRDMA_MAX_FMR_SGES));
	return 0;
	}

	/* FMR mode conveys up to 64 pages of payload per chunk segment.
	*/
	static size_t
	fmr_op_maxpages(struct rpcrdma_xprt *r_xprt)
	{
	return min_t(unsigned int, RPCRDMA_MAX_DATA_SEGS,
	RPCRDMA_MAX_HDR_SEGS * RPCRDMA_MAX_FMR_SGES);
	}

	static int
	fmr_op_init(struct rpcrdma_xprt *r_xprt)
	{
	struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
	int mr_access_flags = IB_ACCESS_REMOTE_WRITE \| IB_ACCESS_REMOTE_READ;
	struct ib_fmr_attr fmr_attr = {
	.max_pages = RPCRDMA_MAX_FMR_SGES,
	.max_maps = 1,
	.page_shift = PAGE_SHIFT
	};
	struct ib_pd *pd = r_xprt->rx_ia.ri_pd;
	struct rpcrdma_mw *r;
	int i, rc;

	spin_lock_init(&buf->rb_mwlock);
	INIT_LIST_HEAD(&buf->rb_mws);
	INIT_LIST_HEAD(&buf->rb_all);

	i = max_t(int, RPCRDMA_MAX_DATA_SEGS / RPCRDMA_MAX_FMR_SGES, 1);
	i += 2; /* head + tail */
	i = buf->rb_max_requests; / one set for each RPC slot */
	dprintk("RPC: %s: initalizing %d FMRs\n", __func__, i);

	rc = -ENOMEM;
	while (i--) {
	r = kzalloc(sizeof(*r), GFP_KERNEL);
	if (!r)
	goto out;

	r->fmr.physaddrs = kmalloc(RPCRDMA_MAX_FMR_SGES *
	sizeof(u64), GFP_KERNEL);
	if (!r->fmr.physaddrs)
	goto out_free;

	r->fmr.fmr = ib_alloc_fmr(pd, mr_access_flags, &fmr_attr);
	if (IS_ERR(r->fmr.fmr))
	goto out_fmr_err;

	r->mw_xprt = r_xprt;
	list_add(&r->mw_list, &buf->rb_mws);
	list_add(&r->mw_all, &buf->rb_all);
	}
	return 0;

	out_fmr_err:
	rc = PTR_ERR(r->fmr.fmr);
	dprintk("RPC: %s: ib_alloc_fmr status %i\n", __func__, rc);
	kfree(r->fmr.physaddrs);
	out_free:
	kfree(r);
	out:
	return rc;
	}

	/* Use the ib_map_phys_fmr() verb to register a memory region
	* for remote access via RDMA READ or RDMA WRITE.
	*/
	static int
	fmr_op_map(struct rpcrdma_xprt r_xprt, struct rpcrdma_mr_seg seg,
	int nsegs, bool writing)
	{
	struct rpcrdma_ia *ia = &r_xprt->rx_ia;
	struct ib_device *device = ia->ri_device;
	enum dma_data_direction direction = rpcrdma_data_dir(writing);
	struct rpcrdma_mr_seg *seg1 = seg;
	int len, pageoff, i, rc;
	struct rpcrdma_mw *mw;

	mw = seg1->rl_mw;
	seg1->rl_mw = NULL;
	if (!mw) {
	mw = rpcrdma_get_mw(r_xprt);
	if (!mw)
	return -ENOMEM;
	} else {
	/* this is a retransmit; generate a fresh rkey */
	rc = __fmr_unmap(mw);
	if (rc)
	return rc;
	}

	pageoff = offset_in_page(seg1->mr_offset);
	seg1->mr_offset -= pageoff; /* start of page */
	seg1->mr_len += pageoff;
	len = -pageoff;
	if (nsegs > RPCRDMA_MAX_FMR_SGES)
	nsegs = RPCRDMA_MAX_FMR_SGES;
	for (i = 0; i < nsegs;) {
	rpcrdma_map_one(device, seg, direction);
	mw->fmr.physaddrs[i] = seg->mr_dma;
	len += seg->mr_len;
	++seg;
	++i;
	/* Check for holes */
	if ((i < nsegs && offset_in_page(seg->mr_offset)) \|\|
	offset_in_page((seg-1)->mr_offset + (seg-1)->mr_len))
	break;
	}

	rc = ib_map_phys_fmr(mw->fmr.fmr, mw->fmr.physaddrs,
	i, seg1->mr_dma);
	if (rc)
	goto out_maperr;

	seg1->rl_mw = mw;
	seg1->mr_rkey = mw->fmr.fmr->rkey;
	seg1->mr_base = seg1->mr_dma + pageoff;
	seg1->mr_nsegs = i;
	seg1->mr_len = len;
	return i;

	out_maperr:
	dprintk("RPC: %s: ib_map_phys_fmr %u@0x%llx+%i (%d) status %i\n",
	__func__, len, (unsigned long long)seg1->mr_dma,
	pageoff, i, rc);
	while (i--)
	rpcrdma_unmap_one(device, --seg);
	return rc;
	}

	static void
	__fmr_dma_unmap(struct rpcrdma_xprt r_xprt, struct rpcrdma_mr_seg seg)
	{
	struct ib_device *device = r_xprt->rx_ia.ri_device;
	int nsegs = seg->mr_nsegs;

	while (nsegs--)
	rpcrdma_unmap_one(device, seg++);
	}

	/* Invalidate all memory regions that were registered for "req".
	*
	* Sleeps until it is safe for the host CPU to access the
	* previously mapped memory regions.
	*/
	static void
	fmr_op_unmap_sync(struct rpcrdma_xprt r_xprt, struct rpcrdma_req req)
	{
	struct rpcrdma_mr_seg *seg;
	unsigned int i, nchunks;
	struct rpcrdma_mw *mw;
	LIST_HEAD(unmap_list);
	int rc;

	dprintk("RPC: %s: req %p\n", __func__, req);

	/* ORDER: Invalidate all of the req's MRs first
	*
	* ib_unmap_fmr() is slow, so use a single call instead
	* of one call per mapped MR.
	*/
	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {
	seg = &req->rl_segments[i];
	mw = seg->rl_mw;

	list_add(&mw->fmr.fmr->list, &unmap_list);

	i += seg->mr_nsegs;
	}
	rc = ib_unmap_fmr(&unmap_list);
	if (rc)
	pr_warn("%s: ib_unmap_fmr failed (%i)\n", __func__, rc);

	/* ORDER: Now DMA unmap all of the req's MRs, and return
	* them to the free MW list.
	*/
	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {
	seg = &req->rl_segments[i];

	__fmr_dma_unmap(r_xprt, seg);
	rpcrdma_put_mw(r_xprt, seg->rl_mw);

	i += seg->mr_nsegs;
	seg->mr_nsegs = 0;
	seg->rl_mw = NULL;
	}

	req->rl_nchunks = 0;
	}

	/* Use a slow, safe mechanism to invalidate all memory regions
	* that were registered for "req".
	*
	* In the asynchronous case, DMA unmapping occurs first here
	* because the rpcrdma_mr_seg is released immediately after this
	* call. It's contents won't be available in __fmr_dma_unmap later.
	* FIXME.
	*/
	static void
	fmr_op_unmap_safe(struct rpcrdma_xprt r_xprt, struct rpcrdma_req req,
	bool sync)
	{
	struct rpcrdma_mr_seg *seg;
	struct rpcrdma_mw *mw;
	unsigned int i;

	for (i = 0; req->rl_nchunks; req->rl_nchunks--) {
	seg = &req->rl_segments[i];
	mw = seg->rl_mw;

	if (sync) {
	/* ORDER */
	__fmr_unmap(mw);
	__fmr_dma_unmap(r_xprt, seg);
	rpcrdma_put_mw(r_xprt, mw);
	} else {
	__fmr_dma_unmap(r_xprt, seg);
	__fmr_queue_recovery(mw);
	}

	i += seg->mr_nsegs;
	seg->mr_nsegs = 0;
	seg->rl_mw = NULL;
	}
	}

	static void
	fmr_op_destroy(struct rpcrdma_buffer *buf)
	{
	struct rpcrdma_mw *r;
	int rc;

	while (!list_empty(&buf->rb_all)) {
	r = list_entry(buf->rb_all.next, struct rpcrdma_mw, mw_all);
	list_del(&r->mw_all);
	kfree(r->fmr.physaddrs);

	rc = ib_dealloc_fmr(r->fmr.fmr);
	if (rc)
	dprintk("RPC: %s: ib_dealloc_fmr failed %i\n",
	__func__, rc);

	kfree(r);
	}
	}

	const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops = {
	.ro_map = fmr_op_map,
	.ro_unmap_sync = fmr_op_unmap_sync,
	.ro_unmap_safe = fmr_op_unmap_safe,
	.ro_open = fmr_op_open,
	.ro_maxpages = fmr_op_maxpages,
	.ro_init = fmr_op_init,
	.ro_destroy = fmr_op_destroy,
	.ro_displayname = "fmr",
	};