[linux-2.6-block.git] / net / sunrpc / xprtrdma / fmr_ops.c

/*
 * 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);
	int rc;

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

/* 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_tail(&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];
		mw = seg->rl_mw;

		list_del_init(&mw->fmr.fmr->list);
		__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",
};
Commit	Line	Data
a0ce85f5 CL	1	/*
	2	* Copyright (c) 2015 Oracle. All rights reserved.
	3	* Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
	4	*/
	5
	6	/* Lightweight memory registration using Fast Memory Regions (FMR).
	7	* Referred to sometimes as MTHCAFMR mode.
	8	*
	9	* FMR uses synchronous memory registration and deregistration.
	10	* FMR registration is known to be fast, but FMR deregistration
	11	* can take tens of usecs to complete.
	12	*/
	13
fc7fbb59 CL	14	/* Normal operation
	15	*
	16	* A Memory Region is prepared for RDMA READ or WRITE using the
	17	* ib_map_phys_fmr verb (fmr_op_map). When the RDMA operation is
	18	* finished, the Memory Region is unmapped using the ib_unmap_fmr
	19	* verb (fmr_op_unmap).
	20	*/
	21
	22	/* Transport recovery
	23	*
	24	* After a transport reconnect, fmr_op_map re-uses the MR already
	25	* allocated for the RPC, but generates a fresh rkey then maps the
	26	* MR again. This process is synchronous.
	27	*/
	28
a0ce85f5 CL	29	#include "xprt_rdma.h"
	30
	31	#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
	32	# define RPCDBG_FACILITY RPCDBG_TRANS
	33	#endif
	34
1c9351ee CL	35	/* Maximum scatter/gather per FMR */
	36	#define RPCRDMA_MAX_FMR_SGES (64)
	37
ead3f26e CL	38	static struct workqueue_struct *fmr_recovery_wq;
	39
	40	#define FMR_RECOVERY_WQ_FLAGS (WQ_UNBOUND)
	41
	42	int
	43	fmr_alloc_recovery_wq(void)
	44	{
	45	fmr_recovery_wq = alloc_workqueue("fmr_recovery", WQ_UNBOUND, 0);
	46	return !fmr_recovery_wq ? -ENOMEM : 0;
	47	}
	48
	49	void
	50	fmr_destroy_recovery_wq(void)
	51	{
	52	struct workqueue_struct *wq;
	53
	54	if (!fmr_recovery_wq)
	55	return;
	56
	57	wq = fmr_recovery_wq;
	58	fmr_recovery_wq = NULL;
	59	destroy_workqueue(wq);
	60	}
	61
	62	static int
	63	__fmr_unmap(struct rpcrdma_mw *mw)
	64	{
	65	LIST_HEAD(l);
38f1932e	66	int rc;
ead3f26e CL	67
ead3f26e CL	68	list_add(&mw->fmr.fmr->list, &l);
38f1932e CL	69	rc = ib_unmap_fmr(&l);
	70	list_del_init(&mw->fmr.fmr->list);
	71	return rc;
ead3f26e CL	72	}
	73
	74	/* Deferred reset of a single FMR. Generate a fresh rkey by
	75	* replacing the MR. There's no recovery if this fails.
	76	*/
	77	static void
	78	__fmr_recovery_worker(struct work_struct *work)
	79	{
	80	struct rpcrdma_mw *mw = container_of(work, struct rpcrdma_mw,
	81	mw_work);
	82	struct rpcrdma_xprt *r_xprt = mw->mw_xprt;
	83
	84	__fmr_unmap(mw);
	85	rpcrdma_put_mw(r_xprt, mw);
	86	return;
	87	}
	88
	89	/* A broken MR was discovered in a context that can't sleep.
	90	* Defer recovery to the recovery worker.
	91	*/
	92	static void
	93	__fmr_queue_recovery(struct rpcrdma_mw *mw)
	94	{
	95	INIT_WORK(&mw->mw_work, __fmr_recovery_worker);
	96	queue_work(fmr_recovery_wq, &mw->mw_work);
	97	}
	98
3968cb58 CL	99	static int
	100	fmr_op_open(struct rpcrdma_ia ia, struct rpcrdma_ep ep,
	101	struct rpcrdma_create_data_internal *cdata)
	102	{
302d3deb CL	103	rpcrdma_set_max_header_sizes(ia, cdata, max_t(unsigned int, 1,
	104	RPCRDMA_MAX_DATA_SEGS /
	105	RPCRDMA_MAX_FMR_SGES));
3968cb58 CL	106	return 0;
	107	}
	108
1c9351ee CL	109	/* FMR mode conveys up to 64 pages of payload per chunk segment.
	110	*/
	111	static size_t
	112	fmr_op_maxpages(struct rpcrdma_xprt *r_xprt)
	113	{
	114	return min_t(unsigned int, RPCRDMA_MAX_DATA_SEGS,
94931746	115	RPCRDMA_MAX_HDR_SEGS * RPCRDMA_MAX_FMR_SGES);
1c9351ee CL	116	}
1c9351ee CL	117
91e70e70 CL	118	static int
	119	fmr_op_init(struct rpcrdma_xprt *r_xprt)
	120	{
	121	struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
	122	int mr_access_flags = IB_ACCESS_REMOTE_WRITE \| IB_ACCESS_REMOTE_READ;
	123	struct ib_fmr_attr fmr_attr = {
	124	.max_pages = RPCRDMA_MAX_FMR_SGES,
	125	.max_maps = 1,
	126	.page_shift = PAGE_SHIFT
	127	};
	128	struct ib_pd *pd = r_xprt->rx_ia.ri_pd;
	129	struct rpcrdma_mw *r;
	130	int i, rc;
	131
58d1dcf5	132	spin_lock_init(&buf->rb_mwlock);
91e70e70 CL	133	INIT_LIST_HEAD(&buf->rb_mws);
	134	INIT_LIST_HEAD(&buf->rb_all);
	135
40c6ed0c CL	136	i = max_t(int, RPCRDMA_MAX_DATA_SEGS / RPCRDMA_MAX_FMR_SGES, 1);
	137	i += 2; /* head + tail */
	138	i = buf->rb_max_requests; / one set for each RPC slot */
	139	dprintk("RPC: %s: initalizing %d FMRs\n", __func__, i);
91e70e70	140
acb9da7a	141	rc = -ENOMEM;
91e70e70 CL	142	while (i--) {
	143	r = kzalloc(sizeof(*r), GFP_KERNEL);
	144	if (!r)
acb9da7a CL	145	goto out;
acb9da7a CL	146
c882a655 CL	147	r->fmr.physaddrs = kmalloc(RPCRDMA_MAX_FMR_SGES *
	148	sizeof(u64), GFP_KERNEL);
	149	if (!r->fmr.physaddrs)
acb9da7a	150	goto out_free;
91e70e70	151
c882a655 CL	152	r->fmr.fmr = ib_alloc_fmr(pd, mr_access_flags, &fmr_attr);
c882a655 CL	153	if (IS_ERR(r->fmr.fmr))
91e70e70 CL	154	goto out_fmr_err;
91e70e70 CL	155
ead3f26e	156	r->mw_xprt = r_xprt;
91e70e70 CL	157	list_add(&r->mw_list, &buf->rb_mws);
	158	list_add(&r->mw_all, &buf->rb_all);
	159	}
	160	return 0;
	161
	162	out_fmr_err:
c882a655	163	rc = PTR_ERR(r->fmr.fmr);
91e70e70	164	dprintk("RPC: %s: ib_alloc_fmr status %i\n", __func__, rc);
c882a655	165	kfree(r->fmr.physaddrs);
acb9da7a	166	out_free:
91e70e70	167	kfree(r);
acb9da7a	168	out:
91e70e70 CL	169	return rc;
	170	}
	171
9c1b4d77 CL	172	/* Use the ib_map_phys_fmr() verb to register a memory region
	173	* for remote access via RDMA READ or RDMA WRITE.
	174	*/
	175	static int
	176	fmr_op_map(struct rpcrdma_xprt r_xprt, struct rpcrdma_mr_seg seg,
	177	int nsegs, bool writing)
	178	{
	179	struct rpcrdma_ia *ia = &r_xprt->rx_ia;
89e0d112	180	struct ib_device *device = ia->ri_device;
d654788e	181	enum dma_data_direction direction = rpcrdma_data_dir(writing);
9c1b4d77	182	struct rpcrdma_mr_seg *seg1 = seg;
9c1b4d77	183	int len, pageoff, i, rc;
fc7fbb59 CL	184	struct rpcrdma_mw *mw;
	185
	186	mw = seg1->rl_mw;
	187	seg1->rl_mw = NULL;
	188	if (!mw) {
	189	mw = rpcrdma_get_mw(r_xprt);
	190	if (!mw)
	191	return -ENOMEM;
	192	} else {
	193	/* this is a retransmit; generate a fresh rkey */
	194	rc = __fmr_unmap(mw);
	195	if (rc)
	196	return rc;
	197	}
9c1b4d77 CL	198
	199	pageoff = offset_in_page(seg1->mr_offset);
	200	seg1->mr_offset -= pageoff; /* start of page */
	201	seg1->mr_len += pageoff;
	202	len = -pageoff;
	203	if (nsegs > RPCRDMA_MAX_FMR_SGES)
	204	nsegs = RPCRDMA_MAX_FMR_SGES;
	205	for (i = 0; i < nsegs;) {
d654788e	206	rpcrdma_map_one(device, seg, direction);
c882a655	207	mw->fmr.physaddrs[i] = seg->mr_dma;
9c1b4d77 CL	208	len += seg->mr_len;
	209	++seg;
	210	++i;
	211	/* Check for holes */
	212	if ((i < nsegs && offset_in_page(seg->mr_offset)) \|\|
	213	offset_in_page((seg-1)->mr_offset + (seg-1)->mr_len))
	214	break;
	215	}
	216
c882a655	217	rc = ib_map_phys_fmr(mw->fmr.fmr, mw->fmr.physaddrs,
acb9da7a	218	i, seg1->mr_dma);
9c1b4d77 CL	219	if (rc)
	220	goto out_maperr;
	221
fc7fbb59	222	seg1->rl_mw = mw;
c882a655	223	seg1->mr_rkey = mw->fmr.fmr->rkey;
9c1b4d77 CL	224	seg1->mr_base = seg1->mr_dma + pageoff;
	225	seg1->mr_nsegs = i;
	226	seg1->mr_len = len;
	227	return i;
	228
	229	out_maperr:
	230	dprintk("RPC: %s: ib_map_phys_fmr %u@0x%llx+%i (%d) status %i\n",
	231	__func__, len, (unsigned long long)seg1->mr_dma,
	232	pageoff, i, rc);
	233	while (i--)
d654788e	234	rpcrdma_unmap_one(device, --seg);
9c1b4d77 CL	235	return rc;
	236	}
	237
7c7a5390 CL	238	static void
	239	__fmr_dma_unmap(struct rpcrdma_xprt r_xprt, struct rpcrdma_mr_seg seg)
	240	{
	241	struct ib_device *device = r_xprt->rx_ia.ri_device;
7c7a5390 CL	242	int nsegs = seg->mr_nsegs;
7c7a5390 CL	243
7c7a5390 CL	244	while (nsegs--)
7c7a5390 CL	245	rpcrdma_unmap_one(device, seg++);
7c7a5390 CL	246	}
	247
	248	/* Invalidate all memory regions that were registered for "req".
	249	*
	250	* Sleeps until it is safe for the host CPU to access the
	251	* previously mapped memory regions.
	252	*/
	253	static void
	254	fmr_op_unmap_sync(struct rpcrdma_xprt r_xprt, struct rpcrdma_req req)
	255	{
	256	struct rpcrdma_mr_seg *seg;
	257	unsigned int i, nchunks;
	258	struct rpcrdma_mw *mw;
	259	LIST_HEAD(unmap_list);
	260	int rc;
	261
	262	dprintk("RPC: %s: req %p\n", __func__, req);
	263
	264	/* ORDER: Invalidate all of the req's MRs first
	265	*
	266	* ib_unmap_fmr() is slow, so use a single call instead
	267	* of one call per mapped MR.
	268	*/
	269	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {
	270	seg = &req->rl_segments[i];
	271	mw = seg->rl_mw;
	272
38f1932e	273	list_add_tail(&mw->fmr.fmr->list, &unmap_list);
7c7a5390 CL	274
	275	i += seg->mr_nsegs;
	276	}
	277	rc = ib_unmap_fmr(&unmap_list);
	278	if (rc)
	279	pr_warn("%s: ib_unmap_fmr failed (%i)\n", __func__, rc);
	280
	281	/* ORDER: Now DMA unmap all of the req's MRs, and return
	282	* them to the free MW list.
	283	*/
	284	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {
	285	seg = &req->rl_segments[i];
38f1932e	286	mw = seg->rl_mw;
7c7a5390	287
38f1932e	288	list_del_init(&mw->fmr.fmr->list);
7c7a5390	289	__fmr_dma_unmap(r_xprt, seg);
763bc230	290	rpcrdma_put_mw(r_xprt, seg->rl_mw);
7c7a5390 CL	291
	292	i += seg->mr_nsegs;
	293	seg->mr_nsegs = 0;
763bc230	294	seg->rl_mw = NULL;
7c7a5390 CL	295	}
	296
	297	req->rl_nchunks = 0;
	298	}
	299
ead3f26e CL	300	/* Use a slow, safe mechanism to invalidate all memory regions
	301	* that were registered for "req".
	302	*
	303	* In the asynchronous case, DMA unmapping occurs first here
	304	* because the rpcrdma_mr_seg is released immediately after this
	305	* call. It's contents won't be available in __fmr_dma_unmap later.
	306	* FIXME.
	307	*/
	308	static void
	309	fmr_op_unmap_safe(struct rpcrdma_xprt r_xprt, struct rpcrdma_req req,
	310	bool sync)
	311	{
	312	struct rpcrdma_mr_seg *seg;
	313	struct rpcrdma_mw *mw;
	314	unsigned int i;
	315
	316	for (i = 0; req->rl_nchunks; req->rl_nchunks--) {
	317	seg = &req->rl_segments[i];
	318	mw = seg->rl_mw;
	319
	320	if (sync) {
	321	/* ORDER */
	322	__fmr_unmap(mw);
	323	__fmr_dma_unmap(r_xprt, seg);
	324	rpcrdma_put_mw(r_xprt, mw);
	325	} else {
	326	__fmr_dma_unmap(r_xprt, seg);
	327	__fmr_queue_recovery(mw);
	328	}
	329
	330	i += seg->mr_nsegs;
	331	seg->mr_nsegs = 0;
	332	seg->rl_mw = NULL;
	333	}
	334	}
	335
4561f347 CL	336	static void
	337	fmr_op_destroy(struct rpcrdma_buffer *buf)
	338	{
	339	struct rpcrdma_mw *r;
	340	int rc;
	341
	342	while (!list_empty(&buf->rb_all)) {
	343	r = list_entry(buf->rb_all.next, struct rpcrdma_mw, mw_all);
	344	list_del(&r->mw_all);
c882a655	345	kfree(r->fmr.physaddrs);
acb9da7a	346
c882a655	347	rc = ib_dealloc_fmr(r->fmr.fmr);
4561f347 CL	348	if (rc)
	349	dprintk("RPC: %s: ib_dealloc_fmr failed %i\n",
	350	__func__, rc);
acb9da7a	351
4561f347 CL	352	kfree(r);
	353	}
	354	}
	355
a0ce85f5	356	const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops = {
9c1b4d77	357	.ro_map = fmr_op_map,
7c7a5390	358	.ro_unmap_sync = fmr_op_unmap_sync,
ead3f26e	359	.ro_unmap_safe = fmr_op_unmap_safe,
3968cb58	360	.ro_open = fmr_op_open,
1c9351ee	361	.ro_maxpages = fmr_op_maxpages,
91e70e70	362	.ro_init = fmr_op_init,
4561f347	363	.ro_destroy = fmr_op_destroy,
a0ce85f5 CL	364	.ro_displayname = "fmr",
a0ce85f5 CL	365	};