[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)

/* Access mode of externally registered pages */
enum {
	RPCRDMA_FMR_ACCESS_FLAGS	= IB_ACCESS_REMOTE_WRITE |
					  IB_ACCESS_REMOTE_READ,
};

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_init(struct rpcrdma_mw *mw, struct ib_pd *pd)
{
	static struct ib_fmr_attr fmr_attr = {
		.max_pages	= RPCRDMA_MAX_FMR_SGES,
		.max_maps	= 1,
		.page_shift	= PAGE_SHIFT
	};

	mw->fmr.fm_physaddrs = kcalloc(RPCRDMA_MAX_FMR_SGES,
				       sizeof(u64), GFP_KERNEL);
	if (!mw->fmr.fm_physaddrs)
		goto out_free;

	mw->mw_sg = kcalloc(RPCRDMA_MAX_FMR_SGES,
			    sizeof(*mw->mw_sg), GFP_KERNEL);
	if (!mw->mw_sg)
		goto out_free;

	sg_init_table(mw->mw_sg, RPCRDMA_MAX_FMR_SGES);

	mw->fmr.fm_mr = ib_alloc_fmr(pd, RPCRDMA_FMR_ACCESS_FLAGS,
				     &fmr_attr);
	if (IS_ERR(mw->fmr.fm_mr))
		goto out_fmr_err;

	return 0;

out_fmr_err:
	dprintk("RPC:       %s: ib_alloc_fmr returned %ld\n", __func__,
		PTR_ERR(mw->fmr.fm_mr));

out_free:
	kfree(mw->mw_sg);
	kfree(mw->fmr.fm_physaddrs);
	return -ENOMEM;
}

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

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

static void
__fmr_release(struct rpcrdma_mw *r)
{
	int rc;

	kfree(r->fmr.fm_physaddrs);
	kfree(r->mw_sg);

	rc = ib_dealloc_fmr(r->fmr.fm_mr);
	if (rc)
		pr_err("rpcrdma: final ib_dealloc_fmr for %p returned %i\n",
		       r, 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;
	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);

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

		rc = __fmr_init(r, pd);
		if (rc) {
			kfree(r);
			return rc;
		}

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

/* 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.fm_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.fm_mr, mw->fmr.fm_physaddrs,
			     i, seg1->mr_dma);
	if (rc)
		goto out_maperr;

	seg1->rl_mw = mw;
	seg1->mr_rkey = mw->fmr.fm_mr->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;
}

/* 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.fm_mr->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.fm_mr->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;

	while (!list_empty(&buf->rb_all)) {
		r = list_entry(buf->rb_all.next, struct rpcrdma_mw, mw_all);
		list_del(&r->mw_all);
		__fmr_release(r);
		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
d48b1d29 CL	38	/* Access mode of externally registered pages */
	39	enum {
	40	RPCRDMA_FMR_ACCESS_FLAGS = IB_ACCESS_REMOTE_WRITE \|
	41	IB_ACCESS_REMOTE_READ,
	42	};
	43
ead3f26e CL	44	static struct workqueue_struct *fmr_recovery_wq;
	45
	46	#define FMR_RECOVERY_WQ_FLAGS (WQ_UNBOUND)
	47
	48	int
	49	fmr_alloc_recovery_wq(void)
	50	{
	51	fmr_recovery_wq = alloc_workqueue("fmr_recovery", WQ_UNBOUND, 0);
	52	return !fmr_recovery_wq ? -ENOMEM : 0;
	53	}
	54
	55	void
	56	fmr_destroy_recovery_wq(void)
	57	{
	58	struct workqueue_struct *wq;
	59
	60	if (!fmr_recovery_wq)
	61	return;
	62
	63	wq = fmr_recovery_wq;
	64	fmr_recovery_wq = NULL;
	65	destroy_workqueue(wq);
	66	}
	67
d48b1d29 CL	68	static int
	69	__fmr_init(struct rpcrdma_mw mw, struct ib_pd pd)
	70	{
	71	static struct ib_fmr_attr fmr_attr = {
	72	.max_pages = RPCRDMA_MAX_FMR_SGES,
	73	.max_maps = 1,
	74	.page_shift = PAGE_SHIFT
	75	};
	76
88975ebe CL	77	mw->fmr.fm_physaddrs = kcalloc(RPCRDMA_MAX_FMR_SGES,
	78	sizeof(u64), GFP_KERNEL);
	79	if (!mw->fmr.fm_physaddrs)
d48b1d29 CL	80	goto out_free;
	81
	82	mw->mw_sg = kcalloc(RPCRDMA_MAX_FMR_SGES,
	83	sizeof(*mw->mw_sg), GFP_KERNEL);
	84	if (!mw->mw_sg)
	85	goto out_free;
	86
	87	sg_init_table(mw->mw_sg, RPCRDMA_MAX_FMR_SGES);
	88
88975ebe CL	89	mw->fmr.fm_mr = ib_alloc_fmr(pd, RPCRDMA_FMR_ACCESS_FLAGS,
	90	&fmr_attr);
	91	if (IS_ERR(mw->fmr.fm_mr))
d48b1d29 CL	92	goto out_fmr_err;
	93
	94	return 0;
	95
	96	out_fmr_err:
	97	dprintk("RPC: %s: ib_alloc_fmr returned %ld\n", __func__,
88975ebe	98	PTR_ERR(mw->fmr.fm_mr));
d48b1d29 CL	99
	100	out_free:
	101	kfree(mw->mw_sg);
88975ebe	102	kfree(mw->fmr.fm_physaddrs);
d48b1d29 CL	103	return -ENOMEM;
	104	}
	105
ead3f26e CL	106	static int
	107	__fmr_unmap(struct rpcrdma_mw *mw)
	108	{
	109	LIST_HEAD(l);
38f1932e	110	int rc;
ead3f26e	111
88975ebe	112	list_add(&mw->fmr.fm_mr->list, &l);
38f1932e	113	rc = ib_unmap_fmr(&l);
88975ebe	114	list_del_init(&mw->fmr.fm_mr->list);
38f1932e	115	return rc;
ead3f26e CL	116	}
ead3f26e CL	117
d48b1d29 CL	118	static void
	119	__fmr_dma_unmap(struct rpcrdma_xprt r_xprt, struct rpcrdma_mr_seg seg)
	120	{
	121	struct ib_device *device = r_xprt->rx_ia.ri_device;
	122	int nsegs = seg->mr_nsegs;
	123
	124	while (nsegs--)
	125	rpcrdma_unmap_one(device, seg++);
	126	}
	127
	128	static void
	129	__fmr_release(struct rpcrdma_mw *r)
	130	{
	131	int rc;
	132
88975ebe	133	kfree(r->fmr.fm_physaddrs);
d48b1d29 CL	134	kfree(r->mw_sg);
d48b1d29 CL	135
88975ebe	136	rc = ib_dealloc_fmr(r->fmr.fm_mr);
d48b1d29 CL	137	if (rc)
	138	pr_err("rpcrdma: final ib_dealloc_fmr for %p returned %i\n",
	139	r, rc);
	140	}
	141
ead3f26e CL	142	/* Deferred reset of a single FMR. Generate a fresh rkey by
	143	* replacing the MR. There's no recovery if this fails.
	144	*/
	145	static void
	146	__fmr_recovery_worker(struct work_struct *work)
	147	{
	148	struct rpcrdma_mw *mw = container_of(work, struct rpcrdma_mw,
	149	mw_work);
	150	struct rpcrdma_xprt *r_xprt = mw->mw_xprt;
	151
	152	__fmr_unmap(mw);
	153	rpcrdma_put_mw(r_xprt, mw);
	154	return;
	155	}
	156
	157	/* A broken MR was discovered in a context that can't sleep.
	158	* Defer recovery to the recovery worker.
	159	*/
	160	static void
	161	__fmr_queue_recovery(struct rpcrdma_mw *mw)
	162	{
	163	INIT_WORK(&mw->mw_work, __fmr_recovery_worker);
	164	queue_work(fmr_recovery_wq, &mw->mw_work);
	165	}
	166
3968cb58 CL	167	static int
	168	fmr_op_open(struct rpcrdma_ia ia, struct rpcrdma_ep ep,
	169	struct rpcrdma_create_data_internal *cdata)
	170	{
302d3deb CL	171	rpcrdma_set_max_header_sizes(ia, cdata, max_t(unsigned int, 1,
	172	RPCRDMA_MAX_DATA_SEGS /
	173	RPCRDMA_MAX_FMR_SGES));
3968cb58 CL	174	return 0;
	175	}
	176
1c9351ee CL	177	/* FMR mode conveys up to 64 pages of payload per chunk segment.
	178	*/
	179	static size_t
	180	fmr_op_maxpages(struct rpcrdma_xprt *r_xprt)
	181	{
	182	return min_t(unsigned int, RPCRDMA_MAX_DATA_SEGS,
94931746	183	RPCRDMA_MAX_HDR_SEGS * RPCRDMA_MAX_FMR_SGES);
1c9351ee CL	184	}
1c9351ee CL	185
91e70e70 CL	186	static int
	187	fmr_op_init(struct rpcrdma_xprt *r_xprt)
	188	{
	189	struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
91e70e70 CL	190	struct ib_pd *pd = r_xprt->rx_ia.ri_pd;
	191	struct rpcrdma_mw *r;
	192	int i, rc;
	193
58d1dcf5	194	spin_lock_init(&buf->rb_mwlock);
91e70e70 CL	195	INIT_LIST_HEAD(&buf->rb_mws);
	196	INIT_LIST_HEAD(&buf->rb_all);
	197
40c6ed0c CL	198	i = max_t(int, RPCRDMA_MAX_DATA_SEGS / RPCRDMA_MAX_FMR_SGES, 1);
	199	i += 2; /* head + tail */
	200	i = buf->rb_max_requests; / one set for each RPC slot */
	201	dprintk("RPC: %s: initalizing %d FMRs\n", __func__, i);
91e70e70 CL	202
	203	while (i--) {
	204	r = kzalloc(sizeof(*r), GFP_KERNEL);
	205	if (!r)
d48b1d29	206	return -ENOMEM;
91e70e70	207
d48b1d29 CL	208	rc = __fmr_init(r, pd);
	209	if (rc) {
	210	kfree(r);
	211	return rc;
	212	}
91e70e70	213
ead3f26e	214	r->mw_xprt = r_xprt;
91e70e70 CL	215	list_add(&r->mw_list, &buf->rb_mws);
	216	list_add(&r->mw_all, &buf->rb_all);
	217	}
	218	return 0;
91e70e70 CL	219	}
91e70e70 CL	220
9c1b4d77 CL	221	/* Use the ib_map_phys_fmr() verb to register a memory region
	222	* for remote access via RDMA READ or RDMA WRITE.
	223	*/
	224	static int
	225	fmr_op_map(struct rpcrdma_xprt r_xprt, struct rpcrdma_mr_seg seg,
	226	int nsegs, bool writing)
	227	{
	228	struct rpcrdma_ia *ia = &r_xprt->rx_ia;
89e0d112	229	struct ib_device *device = ia->ri_device;
d654788e	230	enum dma_data_direction direction = rpcrdma_data_dir(writing);
9c1b4d77	231	struct rpcrdma_mr_seg *seg1 = seg;
9c1b4d77	232	int len, pageoff, i, rc;
fc7fbb59 CL	233	struct rpcrdma_mw *mw;
	234
	235	mw = seg1->rl_mw;
	236	seg1->rl_mw = NULL;
	237	if (!mw) {
	238	mw = rpcrdma_get_mw(r_xprt);
	239	if (!mw)
	240	return -ENOMEM;
	241	} else {
	242	/* this is a retransmit; generate a fresh rkey */
	243	rc = __fmr_unmap(mw);
	244	if (rc)
	245	return rc;
	246	}
9c1b4d77 CL	247
	248	pageoff = offset_in_page(seg1->mr_offset);
	249	seg1->mr_offset -= pageoff; /* start of page */
	250	seg1->mr_len += pageoff;
	251	len = -pageoff;
	252	if (nsegs > RPCRDMA_MAX_FMR_SGES)
	253	nsegs = RPCRDMA_MAX_FMR_SGES;
	254	for (i = 0; i < nsegs;) {
d654788e	255	rpcrdma_map_one(device, seg, direction);
88975ebe	256	mw->fmr.fm_physaddrs[i] = seg->mr_dma;
9c1b4d77 CL	257	len += seg->mr_len;
	258	++seg;
	259	++i;
	260	/* Check for holes */
	261	if ((i < nsegs && offset_in_page(seg->mr_offset)) \|\|
	262	offset_in_page((seg-1)->mr_offset + (seg-1)->mr_len))
	263	break;
	264	}
	265
88975ebe	266	rc = ib_map_phys_fmr(mw->fmr.fm_mr, mw->fmr.fm_physaddrs,
acb9da7a	267	i, seg1->mr_dma);
9c1b4d77 CL	268	if (rc)
	269	goto out_maperr;
	270
fc7fbb59	271	seg1->rl_mw = mw;
88975ebe	272	seg1->mr_rkey = mw->fmr.fm_mr->rkey;
9c1b4d77 CL	273	seg1->mr_base = seg1->mr_dma + pageoff;
	274	seg1->mr_nsegs = i;
	275	seg1->mr_len = len;
	276	return i;
	277
	278	out_maperr:
	279	dprintk("RPC: %s: ib_map_phys_fmr %u@0x%llx+%i (%d) status %i\n",
	280	__func__, len, (unsigned long long)seg1->mr_dma,
	281	pageoff, i, rc);
	282	while (i--)
d654788e	283	rpcrdma_unmap_one(device, --seg);
9c1b4d77 CL	284	return rc;
	285	}
	286
7c7a5390 CL	287	/* Invalidate all memory regions that were registered for "req".
	288	*
	289	* Sleeps until it is safe for the host CPU to access the
	290	* previously mapped memory regions.
	291	*/
	292	static void
	293	fmr_op_unmap_sync(struct rpcrdma_xprt r_xprt, struct rpcrdma_req req)
	294	{
	295	struct rpcrdma_mr_seg *seg;
	296	unsigned int i, nchunks;
	297	struct rpcrdma_mw *mw;
	298	LIST_HEAD(unmap_list);
	299	int rc;
	300
	301	dprintk("RPC: %s: req %p\n", __func__, req);
	302
	303	/* ORDER: Invalidate all of the req's MRs first
	304	*
	305	* ib_unmap_fmr() is slow, so use a single call instead
	306	* of one call per mapped MR.
	307	*/
	308	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {
	309	seg = &req->rl_segments[i];
	310	mw = seg->rl_mw;
	311
88975ebe	312	list_add_tail(&mw->fmr.fm_mr->list, &unmap_list);
7c7a5390 CL	313
	314	i += seg->mr_nsegs;
	315	}
	316	rc = ib_unmap_fmr(&unmap_list);
	317	if (rc)
	318	pr_warn("%s: ib_unmap_fmr failed (%i)\n", __func__, rc);
	319
	320	/* ORDER: Now DMA unmap all of the req's MRs, and return
	321	* them to the free MW list.
	322	*/
	323	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {
	324	seg = &req->rl_segments[i];
38f1932e	325	mw = seg->rl_mw;
7c7a5390	326
88975ebe	327	list_del_init(&mw->fmr.fm_mr->list);
7c7a5390	328	__fmr_dma_unmap(r_xprt, seg);
763bc230	329	rpcrdma_put_mw(r_xprt, seg->rl_mw);
7c7a5390 CL	330
	331	i += seg->mr_nsegs;
	332	seg->mr_nsegs = 0;
763bc230	333	seg->rl_mw = NULL;
7c7a5390 CL	334	}
	335
	336	req->rl_nchunks = 0;
	337	}
	338
ead3f26e CL	339	/* Use a slow, safe mechanism to invalidate all memory regions
	340	* that were registered for "req".
	341	*
	342	* In the asynchronous case, DMA unmapping occurs first here
	343	* because the rpcrdma_mr_seg is released immediately after this
	344	* call. It's contents won't be available in __fmr_dma_unmap later.
	345	* FIXME.
	346	*/
	347	static void
	348	fmr_op_unmap_safe(struct rpcrdma_xprt r_xprt, struct rpcrdma_req req,
	349	bool sync)
	350	{
	351	struct rpcrdma_mr_seg *seg;
	352	struct rpcrdma_mw *mw;
	353	unsigned int i;
	354
	355	for (i = 0; req->rl_nchunks; req->rl_nchunks--) {
	356	seg = &req->rl_segments[i];
	357	mw = seg->rl_mw;
	358
	359	if (sync) {
	360	/* ORDER */
	361	__fmr_unmap(mw);
	362	__fmr_dma_unmap(r_xprt, seg);
	363	rpcrdma_put_mw(r_xprt, mw);
	364	} else {
	365	__fmr_dma_unmap(r_xprt, seg);
	366	__fmr_queue_recovery(mw);
	367	}
	368
	369	i += seg->mr_nsegs;
	370	seg->mr_nsegs = 0;
	371	seg->rl_mw = NULL;
	372	}
	373	}
	374
4561f347 CL	375	static void
	376	fmr_op_destroy(struct rpcrdma_buffer *buf)
	377	{
	378	struct rpcrdma_mw *r;
4561f347 CL	379
	380	while (!list_empty(&buf->rb_all)) {
	381	r = list_entry(buf->rb_all.next, struct rpcrdma_mw, mw_all);
	382	list_del(&r->mw_all);
d48b1d29	383	__fmr_release(r);
4561f347 CL	384	kfree(r);
	385	}
	386	}
	387
a0ce85f5	388	const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops = {
9c1b4d77	389	.ro_map = fmr_op_map,
7c7a5390	390	.ro_unmap_sync = fmr_op_unmap_sync,
ead3f26e	391	.ro_unmap_safe = fmr_op_unmap_safe,
3968cb58	392	.ro_open = fmr_op_open,
1c9351ee	393	.ro_maxpages = fmr_op_maxpages,
91e70e70	394	.ro_init = fmr_op_init,
4561f347	395	.ro_destroy = fmr_op_destroy,
a0ce85f5 CL	396	.ro_displayname = "fmr",
a0ce85f5 CL	397	};