1/*
   2 * Module for pnfs flexfile layout driver.
   3 *
   4 * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
   5 *
   6 * Tao Peng <bergwolf@primarydata.com>
   7 */
   8
   9#include <linux/nfs_fs.h>
 
  10#include <linux/nfs_page.h>
  11#include <linux/module.h>
 
  12
  13#include <linux/sunrpc/metrics.h>
  14
  15#include "flexfilelayout.h"
  16#include "../nfs4session.h"
  17#include "../nfs4idmap.h"
  18#include "../internal.h"
  19#include "../delegation.h"
  20#include "../nfs4trace.h"
  21#include "../iostat.h"
  22#include "../nfs.h"
  23#include "../nfs42.h"
  24
  25#define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  26
  27#define FF_LAYOUT_POLL_RETRY_MAX     (15*HZ)
  28#define FF_LAYOUTRETURN_MAXERR 20
  29
 
 
 
 
  30
  31static struct group_info	*ff_zero_group;
  32
 
  33static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
  34		struct nfs_pgio_header *hdr);
  35static int ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
 
  36			       struct nfs42_layoutstat_devinfo *devinfo,
  37			       int dev_limit);
  38static void ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
  39			      const struct nfs42_layoutstat_devinfo *devinfo,
  40			      struct nfs4_ff_layout_mirror *mirror);
  41
  42static struct pnfs_layout_hdr *
  43ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
  44{
  45	struct nfs4_flexfile_layout *ffl;
  46
  47	ffl = kzalloc(sizeof(*ffl), gfp_flags);
  48	if (ffl) {
 
  49		INIT_LIST_HEAD(&ffl->error_list);
  50		INIT_LIST_HEAD(&ffl->mirrors);
  51		ffl->last_report_time = ktime_get();
 
  52		return &ffl->generic_hdr;
  53	} else
  54		return NULL;
  55}
  56
  57static void
  58ff_layout_free_layout_hdr(struct pnfs_layout_hdr *lo)
  59{
 
  60	struct nfs4_ff_layout_ds_err *err, *n;
  61
  62	list_for_each_entry_safe(err, n, &FF_LAYOUT_FROM_HDR(lo)->error_list,
  63				 list) {
  64		list_del(&err->list);
  65		kfree(err);
  66	}
  67	kfree(FF_LAYOUT_FROM_HDR(lo));
  68}
  69
  70static int decode_pnfs_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
  71{
  72	__be32 *p;
  73
  74	p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
  75	if (unlikely(p == NULL))
  76		return -ENOBUFS;
  77	stateid->type = NFS4_PNFS_DS_STATEID_TYPE;
  78	memcpy(stateid->data, p, NFS4_STATEID_SIZE);
  79	dprintk("%s: stateid id= [%x%x%x%x]\n", __func__,
  80		p[0], p[1], p[2], p[3]);
  81	return 0;
  82}
  83
  84static int decode_deviceid(struct xdr_stream *xdr, struct nfs4_deviceid *devid)
  85{
  86	__be32 *p;
  87
  88	p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE);
  89	if (unlikely(!p))
  90		return -ENOBUFS;
  91	memcpy(devid, p, NFS4_DEVICEID4_SIZE);
  92	nfs4_print_deviceid(devid);
  93	return 0;
  94}
  95
  96static int decode_nfs_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
  97{
  98	__be32 *p;
  99
 100	p = xdr_inline_decode(xdr, 4);
 101	if (unlikely(!p))
 102		return -ENOBUFS;
 103	fh->size = be32_to_cpup(p++);
 104	if (fh->size > sizeof(struct nfs_fh)) {
 105		printk(KERN_ERR "NFS flexfiles: Too big fh received %d\n",
 106		       fh->size);
 107		return -EOVERFLOW;
 108	}
 109	/* fh.data */
 110	p = xdr_inline_decode(xdr, fh->size);
 111	if (unlikely(!p))
 112		return -ENOBUFS;
 113	memcpy(&fh->data, p, fh->size);
 114	dprintk("%s: fh len %d\n", __func__, fh->size);
 115
 116	return 0;
 117}
 118
 119/*
 120 * Currently only stringified uids and gids are accepted.
 121 * I.e., kerberos is not supported to the DSes, so no pricipals.
 122 *
 123 * That means that one common function will suffice, but when
 124 * principals are added, this should be split to accomodate
 125 * calls to both nfs_map_name_to_uid() and nfs_map_group_to_gid().
 126 */
 127static int
 128decode_name(struct xdr_stream *xdr, u32 *id)
 129{
 130	__be32 *p;
 131	int len;
 132
 133	/* opaque_length(4)*/
 134	p = xdr_inline_decode(xdr, 4);
 135	if (unlikely(!p))
 136		return -ENOBUFS;
 137	len = be32_to_cpup(p++);
 138	if (len < 0)
 139		return -EINVAL;
 140
 141	dprintk("%s: len %u\n", __func__, len);
 142
 143	/* opaque body */
 144	p = xdr_inline_decode(xdr, len);
 145	if (unlikely(!p))
 146		return -ENOBUFS;
 147
 148	if (!nfs_map_string_to_numeric((char *)p, len, id))
 149		return -EINVAL;
 150
 151	return 0;
 152}
 153
 154static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
 155		const struct nfs4_ff_layout_mirror *m2)
 156{
 157	int i, j;
 158
 159	if (m1->fh_versions_cnt != m2->fh_versions_cnt)
 160		return false;
 161	for (i = 0; i < m1->fh_versions_cnt; i++) {
 162		bool found_fh = false;
 163		for (j = 0; j < m2->fh_versions_cnt; j++) {
 164			if (nfs_compare_fh(&m1->fh_versions[i],
 165					&m2->fh_versions[j]) == 0) {
 166				found_fh = true;
 167				break;
 168			}
 169		}
 170		if (!found_fh)
 171			return false;
 172	}
 173	return true;
 174}
 175
 176static struct nfs4_ff_layout_mirror *
 177ff_layout_add_mirror(struct pnfs_layout_hdr *lo,
 178		struct nfs4_ff_layout_mirror *mirror)
 179{
 180	struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
 181	struct nfs4_ff_layout_mirror *pos;
 182	struct inode *inode = lo->plh_inode;
 183
 184	spin_lock(&inode->i_lock);
 185	list_for_each_entry(pos, &ff_layout->mirrors, mirrors) {
 186		if (memcmp(&mirror->devid, &pos->devid, sizeof(pos->devid)) != 0)
 187			continue;
 188		if (!ff_mirror_match_fh(mirror, pos))
 189			continue;
 190		if (refcount_inc_not_zero(&pos->ref)) {
 191			spin_unlock(&inode->i_lock);
 192			return pos;
 193		}
 194	}
 195	list_add(&mirror->mirrors, &ff_layout->mirrors);
 196	mirror->layout = lo;
 197	spin_unlock(&inode->i_lock);
 198	return mirror;
 199}
 200
 201static void
 202ff_layout_remove_mirror(struct nfs4_ff_layout_mirror *mirror)
 203{
 204	struct inode *inode;
 205	if (mirror->layout == NULL)
 206		return;
 207	inode = mirror->layout->plh_inode;
 208	spin_lock(&inode->i_lock);
 209	list_del(&mirror->mirrors);
 210	spin_unlock(&inode->i_lock);
 211	mirror->layout = NULL;
 212}
 213
 214static struct nfs4_ff_layout_mirror *ff_layout_alloc_mirror(gfp_t gfp_flags)
 215{
 216	struct nfs4_ff_layout_mirror *mirror;
 217
 218	mirror = kzalloc(sizeof(*mirror), gfp_flags);
 219	if (mirror != NULL) {
 220		spin_lock_init(&mirror->lock);
 221		refcount_set(&mirror->ref, 1);
 222		INIT_LIST_HEAD(&mirror->mirrors);
 223	}
 224	return mirror;
 225}
 226
 227static void ff_layout_free_mirror(struct nfs4_ff_layout_mirror *mirror)
 228{
 229	struct rpc_cred	*cred;
 230
 231	ff_layout_remove_mirror(mirror);
 232	kfree(mirror->fh_versions);
 233	cred = rcu_access_pointer(mirror->ro_cred);
 234	if (cred)
 235		put_rpccred(cred);
 236	cred = rcu_access_pointer(mirror->rw_cred);
 237	if (cred)
 238		put_rpccred(cred);
 239	nfs4_ff_layout_put_deviceid(mirror->mirror_ds);
 240	kfree(mirror);
 241}
 242
 243static void ff_layout_put_mirror(struct nfs4_ff_layout_mirror *mirror)
 244{
 245	if (mirror != NULL && refcount_dec_and_test(&mirror->ref))
 246		ff_layout_free_mirror(mirror);
 247}
 248
 249static void ff_layout_free_mirror_array(struct nfs4_ff_layout_segment *fls)
 250{
 251	int i;
 252
 253	if (fls->mirror_array) {
 254		for (i = 0; i < fls->mirror_array_cnt; i++) {
 255			/* normally mirror_ds is freed in
 256			 * .free_deviceid_node but we still do it here
 257			 * for .alloc_lseg error path */
 258			ff_layout_put_mirror(fls->mirror_array[i]);
 259		}
 260		kfree(fls->mirror_array);
 261		fls->mirror_array = NULL;
 262	}
 263}
 264
 265static int ff_layout_check_layout(struct nfs4_layoutget_res *lgr)
 266{
 267	int ret = 0;
 268
 269	dprintk("--> %s\n", __func__);
 270
 271	/* FIXME: remove this check when layout segment support is added */
 272	if (lgr->range.offset != 0 ||
 273	    lgr->range.length != NFS4_MAX_UINT64) {
 274		dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 275			__func__);
 276		ret = -EINVAL;
 277	}
 278
 279	dprintk("--> %s returns %d\n", __func__, ret);
 280	return ret;
 281}
 282
 283static void _ff_layout_free_lseg(struct nfs4_ff_layout_segment *fls)
 284{
 285	if (fls) {
 286		ff_layout_free_mirror_array(fls);
 287		kfree(fls);
 288	}
 289}
 290
 291static bool
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 292ff_lseg_range_is_after(const struct pnfs_layout_range *l1,
 293		const struct pnfs_layout_range *l2)
 294{
 295	u64 end1, end2;
 296
 297	if (l1->iomode != l2->iomode)
 298		return l1->iomode != IOMODE_READ;
 299	end1 = pnfs_calc_offset_end(l1->offset, l1->length);
 300	end2 = pnfs_calc_offset_end(l2->offset, l2->length);
 301	if (end1 < l2->offset)
 302		return false;
 303	if (end2 < l1->offset)
 304		return true;
 305	return l2->offset <= l1->offset;
 306}
 307
 308static bool
 309ff_lseg_merge(struct pnfs_layout_segment *new,
 310		struct pnfs_layout_segment *old)
 311{
 312	u64 new_end, old_end;
 313
 314	if (test_bit(NFS_LSEG_LAYOUTRETURN, &old->pls_flags))
 315		return false;
 316	if (new->pls_range.iomode != old->pls_range.iomode)
 317		return false;
 318	old_end = pnfs_calc_offset_end(old->pls_range.offset,
 319			old->pls_range.length);
 320	if (old_end < new->pls_range.offset)
 321		return false;
 322	new_end = pnfs_calc_offset_end(new->pls_range.offset,
 323			new->pls_range.length);
 324	if (new_end < old->pls_range.offset)
 325		return false;
 
 
 326
 327	/* Mergeable: copy info from 'old' to 'new' */
 328	if (new_end < old_end)
 329		new_end = old_end;
 330	if (new->pls_range.offset < old->pls_range.offset)
 331		new->pls_range.offset = old->pls_range.offset;
 332	new->pls_range.length = pnfs_calc_offset_length(new->pls_range.offset,
 333			new_end);
 334	if (test_bit(NFS_LSEG_ROC, &old->pls_flags))
 335		set_bit(NFS_LSEG_ROC, &new->pls_flags);
 336	return true;
 337}
 338
 339static void
 340ff_layout_add_lseg(struct pnfs_layout_hdr *lo,
 341		struct pnfs_layout_segment *lseg,
 342		struct list_head *free_me)
 343{
 344	pnfs_generic_layout_insert_lseg(lo, lseg,
 345			ff_lseg_range_is_after,
 346			ff_lseg_merge,
 347			free_me);
 348}
 349
 350static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
 351{
 352	int i, j;
 353
 354	for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
 355		for (j = i + 1; j < fls->mirror_array_cnt; j++)
 356			if (fls->mirror_array[i]->efficiency <
 357			    fls->mirror_array[j]->efficiency)
 358				swap(fls->mirror_array[i],
 359				     fls->mirror_array[j]);
 360	}
 361}
 362
 363static struct pnfs_layout_segment *
 364ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 365		     struct nfs4_layoutget_res *lgr,
 366		     gfp_t gfp_flags)
 367{
 368	struct pnfs_layout_segment *ret;
 369	struct nfs4_ff_layout_segment *fls = NULL;
 370	struct xdr_stream stream;
 371	struct xdr_buf buf;
 372	struct page *scratch;
 373	u64 stripe_unit;
 374	u32 mirror_array_cnt;
 375	__be32 *p;
 376	int i, rc;
 377
 378	dprintk("--> %s\n", __func__);
 379	scratch = alloc_page(gfp_flags);
 380	if (!scratch)
 381		return ERR_PTR(-ENOMEM);
 382
 383	xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages,
 384			      lgr->layoutp->len);
 385	xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 386
 387	/* stripe unit and mirror_array_cnt */
 388	rc = -EIO;
 389	p = xdr_inline_decode(&stream, 8 + 4);
 390	if (!p)
 391		goto out_err_free;
 392
 393	p = xdr_decode_hyper(p, &stripe_unit);
 394	mirror_array_cnt = be32_to_cpup(p++);
 395	dprintk("%s: stripe_unit=%llu mirror_array_cnt=%u\n", __func__,
 396		stripe_unit, mirror_array_cnt);
 397
 398	if (mirror_array_cnt > NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT ||
 399	    mirror_array_cnt == 0)
 400		goto out_err_free;
 401
 402	rc = -ENOMEM;
 403	fls = kzalloc(sizeof(*fls), gfp_flags);
 
 404	if (!fls)
 405		goto out_err_free;
 406
 407	fls->mirror_array_cnt = mirror_array_cnt;
 408	fls->stripe_unit = stripe_unit;
 409	fls->mirror_array = kcalloc(fls->mirror_array_cnt,
 410				    sizeof(fls->mirror_array[0]), gfp_flags);
 411	if (fls->mirror_array == NULL)
 412		goto out_err_free;
 413
 414	for (i = 0; i < fls->mirror_array_cnt; i++) {
 415		struct nfs4_ff_layout_mirror *mirror;
 416		struct auth_cred acred = { .group_info = ff_zero_group };
 417		struct rpc_cred	__rcu *cred;
 
 
 418		u32 ds_count, fh_count, id;
 419		int j;
 420
 421		rc = -EIO;
 422		p = xdr_inline_decode(&stream, 4);
 423		if (!p)
 424			goto out_err_free;
 425		ds_count = be32_to_cpup(p);
 426
 427		/* FIXME: allow for striping? */
 428		if (ds_count != 1)
 429			goto out_err_free;
 430
 431		fls->mirror_array[i] = ff_layout_alloc_mirror(gfp_flags);
 432		if (fls->mirror_array[i] == NULL) {
 433			rc = -ENOMEM;
 434			goto out_err_free;
 435		}
 436
 437		fls->mirror_array[i]->ds_count = ds_count;
 438
 439		/* deviceid */
 440		rc = decode_deviceid(&stream, &fls->mirror_array[i]->devid);
 441		if (rc)
 442			goto out_err_free;
 443
 444		/* efficiency */
 445		rc = -EIO;
 446		p = xdr_inline_decode(&stream, 4);
 447		if (!p)
 448			goto out_err_free;
 449		fls->mirror_array[i]->efficiency = be32_to_cpup(p);
 450
 451		/* stateid */
 452		rc = decode_pnfs_stateid(&stream, &fls->mirror_array[i]->stateid);
 453		if (rc)
 454			goto out_err_free;
 455
 456		/* fh */
 457		rc = -EIO;
 458		p = xdr_inline_decode(&stream, 4);
 459		if (!p)
 460			goto out_err_free;
 461		fh_count = be32_to_cpup(p);
 462
 463		fls->mirror_array[i]->fh_versions =
 464			kzalloc(fh_count * sizeof(struct nfs_fh),
 465				gfp_flags);
 466		if (fls->mirror_array[i]->fh_versions == NULL) {
 467			rc = -ENOMEM;
 468			goto out_err_free;
 469		}
 470
 471		for (j = 0; j < fh_count; j++) {
 472			rc = decode_nfs_fh(&stream,
 473					   &fls->mirror_array[i]->fh_versions[j]);
 474			if (rc)
 475				goto out_err_free;
 476		}
 477
 478		fls->mirror_array[i]->fh_versions_cnt = fh_count;
 479
 480		/* user */
 481		rc = decode_name(&stream, &id);
 482		if (rc)
 483			goto out_err_free;
 484
 485		acred.uid = make_kuid(&init_user_ns, id);
 486
 487		/* group */
 488		rc = decode_name(&stream, &id);
 489		if (rc)
 490			goto out_err_free;
 491
 492		acred.gid = make_kgid(&init_user_ns, id);
 493
 494		/* find the cred for it */
 495		rcu_assign_pointer(cred, rpc_lookup_generic_cred(&acred, 0, gfp_flags));
 496		if (IS_ERR(cred)) {
 497			rc = PTR_ERR(cred);
 498			goto out_err_free;
 
 499		}
 
 
 
 
 
 
 500
 501		if (lgr->range.iomode == IOMODE_READ)
 502			rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 503		else
 504			rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 505
 506		mirror = ff_layout_add_mirror(lh, fls->mirror_array[i]);
 507		if (mirror != fls->mirror_array[i]) {
 508			/* swap cred ptrs so free_mirror will clean up old */
 509			if (lgr->range.iomode == IOMODE_READ) {
 510				cred = xchg(&mirror->ro_cred, cred);
 511				rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 512			} else {
 513				cred = xchg(&mirror->rw_cred, cred);
 514				rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 515			}
 516			ff_layout_free_mirror(fls->mirror_array[i]);
 517			fls->mirror_array[i] = mirror;
 518		}
 519
 520		dprintk("%s: iomode %s uid %u gid %u\n", __func__,
 521			lgr->range.iomode == IOMODE_READ ? "READ" : "RW",
 522			from_kuid(&init_user_ns, acred.uid),
 523			from_kgid(&init_user_ns, acred.gid));
 524	}
 525
 526	p = xdr_inline_decode(&stream, 4);
 527	if (!p)
 528		goto out_sort_mirrors;
 529	fls->flags = be32_to_cpup(p);
 530
 531	p = xdr_inline_decode(&stream, 4);
 532	if (!p)
 533		goto out_sort_mirrors;
 534	for (i=0; i < fls->mirror_array_cnt; i++)
 535		fls->mirror_array[i]->report_interval = be32_to_cpup(p);
 536
 537out_sort_mirrors:
 538	ff_layout_sort_mirrors(fls);
 539	rc = ff_layout_check_layout(lgr);
 540	if (rc)
 541		goto out_err_free;
 542	ret = &fls->generic_hdr;
 543	dprintk("<-- %s (success)\n", __func__);
 544out_free_page:
 545	__free_page(scratch);
 546	return ret;
 547out_err_free:
 548	_ff_layout_free_lseg(fls);
 549	ret = ERR_PTR(rc);
 550	dprintk("<-- %s (%d)\n", __func__, rc);
 551	goto out_free_page;
 552}
 553
 554static bool ff_layout_has_rw_segments(struct pnfs_layout_hdr *layout)
 555{
 556	struct pnfs_layout_segment *lseg;
 557
 558	list_for_each_entry(lseg, &layout->plh_segs, pls_list)
 559		if (lseg->pls_range.iomode == IOMODE_RW)
 560			return true;
 561
 562	return false;
 563}
 564
 565static void
 566ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
 567{
 568	struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 569
 570	dprintk("--> %s\n", __func__);
 571
 572	if (lseg->pls_range.iomode == IOMODE_RW) {
 573		struct nfs4_flexfile_layout *ffl;
 574		struct inode *inode;
 575
 576		ffl = FF_LAYOUT_FROM_HDR(lseg->pls_layout);
 577		inode = ffl->generic_hdr.plh_inode;
 578		spin_lock(&inode->i_lock);
 579		if (!ff_layout_has_rw_segments(lseg->pls_layout)) {
 580			ffl->commit_info.nbuckets = 0;
 581			kfree(ffl->commit_info.buckets);
 582			ffl->commit_info.buckets = NULL;
 583		}
 584		spin_unlock(&inode->i_lock);
 585	}
 586	_ff_layout_free_lseg(fls);
 587}
 588
 589/* Return 1 until we have multiple lsegs support */
 590static int
 591ff_layout_get_lseg_count(struct nfs4_ff_layout_segment *fls)
 592{
 593	return 1;
 594}
 595
 596static void
 597nfs4_ff_start_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 598{
 599	/* first IO request? */
 600	if (atomic_inc_return(&timer->n_ops) == 1) {
 601		timer->start_time = now;
 602	}
 603}
 604
 605static ktime_t
 606nfs4_ff_end_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 607{
 608	ktime_t start;
 609
 610	if (atomic_dec_return(&timer->n_ops) < 0)
 611		WARN_ON_ONCE(1);
 612
 613	start = timer->start_time;
 614	timer->start_time = now;
 615	return ktime_sub(now, start);
 616}
 617
 618static bool
 619nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
 620			    struct nfs4_ff_layoutstat *layoutstat,
 621			    ktime_t now)
 622{
 623	s64 report_interval = FF_LAYOUTSTATS_REPORT_INTERVAL;
 624	struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(mirror->layout);
 625
 626	nfs4_ff_start_busy_timer(&layoutstat->busy_timer, now);
 627	if (!mirror->start_time)
 628		mirror->start_time = now;
 629	if (mirror->report_interval != 0)
 630		report_interval = (s64)mirror->report_interval * 1000LL;
 631	else if (layoutstats_timer != 0)
 632		report_interval = (s64)layoutstats_timer * 1000LL;
 633	if (ktime_to_ms(ktime_sub(now, ffl->last_report_time)) >=
 634			report_interval) {
 635		ffl->last_report_time = now;
 636		return true;
 637	}
 638
 639	return false;
 640}
 641
 642static void
 643nfs4_ff_layout_stat_io_update_requested(struct nfs4_ff_layoutstat *layoutstat,
 644		__u64 requested)
 645{
 646	struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 647
 648	iostat->ops_requested++;
 649	iostat->bytes_requested += requested;
 650}
 651
 652static void
 653nfs4_ff_layout_stat_io_update_completed(struct nfs4_ff_layoutstat *layoutstat,
 654		__u64 requested,
 655		__u64 completed,
 656		ktime_t time_completed,
 657		ktime_t time_started)
 658{
 659	struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 660	ktime_t completion_time = ktime_sub(time_completed, time_started);
 661	ktime_t timer;
 662
 663	iostat->ops_completed++;
 664	iostat->bytes_completed += completed;
 665	iostat->bytes_not_delivered += requested - completed;
 666
 667	timer = nfs4_ff_end_busy_timer(&layoutstat->busy_timer, time_completed);
 668	iostat->total_busy_time =
 669			ktime_add(iostat->total_busy_time, timer);
 670	iostat->aggregate_completion_time =
 671			ktime_add(iostat->aggregate_completion_time,
 672					completion_time);
 673}
 674
 675static void
 676nfs4_ff_layout_stat_io_start_read(struct inode *inode,
 677		struct nfs4_ff_layout_mirror *mirror,
 678		__u64 requested, ktime_t now)
 679{
 680	bool report;
 681
 682	spin_lock(&mirror->lock);
 683	report = nfs4_ff_layoutstat_start_io(mirror, &mirror->read_stat, now);
 684	nfs4_ff_layout_stat_io_update_requested(&mirror->read_stat, requested);
 685	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 686	spin_unlock(&mirror->lock);
 687
 688	if (report)
 689		pnfs_report_layoutstat(inode, GFP_KERNEL);
 690}
 691
 692static void
 693nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
 694		struct nfs4_ff_layout_mirror *mirror,
 695		__u64 requested,
 696		__u64 completed)
 697{
 698	spin_lock(&mirror->lock);
 699	nfs4_ff_layout_stat_io_update_completed(&mirror->read_stat,
 700			requested, completed,
 701			ktime_get(), task->tk_start);
 702	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 703	spin_unlock(&mirror->lock);
 704}
 705
 706static void
 707nfs4_ff_layout_stat_io_start_write(struct inode *inode,
 708		struct nfs4_ff_layout_mirror *mirror,
 709		__u64 requested, ktime_t now)
 710{
 711	bool report;
 712
 713	spin_lock(&mirror->lock);
 714	report = nfs4_ff_layoutstat_start_io(mirror , &mirror->write_stat, now);
 715	nfs4_ff_layout_stat_io_update_requested(&mirror->write_stat, requested);
 716	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 717	spin_unlock(&mirror->lock);
 718
 719	if (report)
 720		pnfs_report_layoutstat(inode, GFP_NOIO);
 721}
 722
 723static void
 724nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
 725		struct nfs4_ff_layout_mirror *mirror,
 726		__u64 requested,
 727		__u64 completed,
 728		enum nfs3_stable_how committed)
 729{
 730	if (committed == NFS_UNSTABLE)
 731		requested = completed = 0;
 732
 733	spin_lock(&mirror->lock);
 734	nfs4_ff_layout_stat_io_update_completed(&mirror->write_stat,
 735			requested, completed, ktime_get(), task->tk_start);
 736	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 737	spin_unlock(&mirror->lock);
 738}
 739
 740static int
 741ff_layout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 742			    struct nfs_commit_info *cinfo,
 743			    gfp_t gfp_flags)
 744{
 745	struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 746	struct pnfs_commit_bucket *buckets;
 747	int size;
 748
 749	if (cinfo->ds->nbuckets != 0) {
 750		/* This assumes there is only one RW lseg per file.
 751		 * To support multiple lseg per file, we need to
 752		 * change struct pnfs_commit_bucket to allow dynamic
 753		 * increasing nbuckets.
 754		 */
 755		return 0;
 756	}
 757
 758	size = ff_layout_get_lseg_count(fls) * FF_LAYOUT_MIRROR_COUNT(lseg);
 
 
 759
 760	buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
 761			  gfp_flags);
 762	if (!buckets)
 763		return -ENOMEM;
 764	else {
 765		int i;
 766
 767		spin_lock(&cinfo->inode->i_lock);
 768		if (cinfo->ds->nbuckets != 0)
 769			kfree(buckets);
 770		else {
 771			cinfo->ds->buckets = buckets;
 772			cinfo->ds->nbuckets = size;
 773			for (i = 0; i < size; i++) {
 774				INIT_LIST_HEAD(&buckets[i].written);
 775				INIT_LIST_HEAD(&buckets[i].committing);
 776				/* mark direct verifier as unset */
 777				buckets[i].direct_verf.committed =
 778					NFS_INVALID_STABLE_HOW;
 779			}
 780		}
 781		spin_unlock(&cinfo->inode->i_lock);
 782		return 0;
 783	}
 784}
 785
 786static struct nfs4_pnfs_ds *
 787ff_layout_choose_best_ds_for_read(struct pnfs_layout_segment *lseg,
 788				  int start_idx,
 789				  int *best_idx)
 790{
 791	struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 
 792	struct nfs4_pnfs_ds *ds;
 793	bool fail_return = false;
 794	int idx;
 795
 796	/* mirrors are sorted by efficiency */
 797	for (idx = start_idx; idx < fls->mirror_array_cnt; idx++) {
 798		if (idx+1 == fls->mirror_array_cnt)
 799			fail_return = true;
 800		ds = nfs4_ff_layout_prepare_ds(lseg, idx, fail_return);
 801		if (ds) {
 802			*best_idx = idx;
 803			return ds;
 804		}
 
 
 
 
 805	}
 806
 807	return NULL;
 808}
 809
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 810static void
 811ff_layout_pg_get_read(struct nfs_pageio_descriptor *pgio,
 812		      struct nfs_page *req,
 813		      bool strict_iomode)
 814{
 815retry_strict:
 816	pnfs_put_lseg(pgio->pg_lseg);
 817	pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 818					   req->wb_context,
 819					   0,
 820					   NFS4_MAX_UINT64,
 821					   IOMODE_READ,
 822					   strict_iomode,
 823					   GFP_KERNEL);
 824	if (IS_ERR(pgio->pg_lseg)) {
 825		pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 826		pgio->pg_lseg = NULL;
 827	}
 
 828
 829	/* If we don't have checking, do get a IOMODE_RW
 830	 * segment, and the server wants to avoid READs
 831	 * there, then retry!
 832	 */
 833	if (pgio->pg_lseg && !strict_iomode &&
 834	    ff_layout_avoid_read_on_rw(pgio->pg_lseg)) {
 835		strict_iomode = true;
 836		goto retry_strict;
 837	}
 838}
 839
 840static void
 841ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 842			struct nfs_page *req)
 843{
 844	struct nfs_pgio_mirror *pgm;
 845	struct nfs4_ff_layout_mirror *mirror;
 846	struct nfs4_pnfs_ds *ds;
 847	int ds_idx;
 848
 849retry:
 850	pnfs_generic_pg_check_layout(pgio);
 851	/* Use full layout for now */
 852	if (!pgio->pg_lseg)
 853		ff_layout_pg_get_read(pgio, req, false);
 854	else if (ff_layout_avoid_read_on_rw(pgio->pg_lseg))
 
 
 
 855		ff_layout_pg_get_read(pgio, req, true);
 
 
 
 856
 857	/* If no lseg, fall back to read through mds */
 858	if (pgio->pg_lseg == NULL)
 859		goto out_mds;
 860
 861	ds = ff_layout_choose_best_ds_for_read(pgio->pg_lseg, 0, &ds_idx);
 862	if (!ds) {
 863		if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 864			goto out_mds;
 865		pnfs_put_lseg(pgio->pg_lseg);
 866		pgio->pg_lseg = NULL;
 867		/* Sleep for 1 second before retrying */
 868		ssleep(1);
 869		goto retry;
 870	}
 871
 872	mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 873
 874	pgio->pg_mirror_idx = ds_idx;
 875
 876	/* read always uses only one mirror - idx 0 for pgio layer */
 877	pgm = &pgio->pg_mirrors[0];
 878	pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
 879
 
 
 
 
 
 880	return;
 
 
 
 881out_mds:
 882	pnfs_put_lseg(pgio->pg_lseg);
 883	pgio->pg_lseg = NULL;
 
 
 
 884	nfs_pageio_reset_read_mds(pgio);
 885}
 886
 887static void
 888ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 889			struct nfs_page *req)
 890{
 891	struct nfs4_ff_layout_mirror *mirror;
 892	struct nfs_pgio_mirror *pgm;
 893	struct nfs_commit_info cinfo;
 894	struct nfs4_pnfs_ds *ds;
 895	int i;
 896	int status;
 897
 898retry:
 899	pnfs_generic_pg_check_layout(pgio);
 900	if (!pgio->pg_lseg) {
 901		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 902						   req->wb_context,
 903						   0,
 904						   NFS4_MAX_UINT64,
 905						   IOMODE_RW,
 906						   false,
 907						   GFP_NOFS);
 908		if (IS_ERR(pgio->pg_lseg)) {
 909			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 910			pgio->pg_lseg = NULL;
 911			return;
 912		}
 913	}
 914	/* If no lseg, fall back to write through mds */
 915	if (pgio->pg_lseg == NULL)
 916		goto out_mds;
 917
 918	nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
 919	status = ff_layout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
 920	if (status < 0)
 921		goto out_mds;
 922
 923	/* Use a direct mapping of ds_idx to pgio mirror_idx */
 924	if (WARN_ON_ONCE(pgio->pg_mirror_count !=
 925	    FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg)))
 926		goto out_mds;
 927
 928	for (i = 0; i < pgio->pg_mirror_count; i++) {
 929		ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, i, true);
 
 930		if (!ds) {
 931			if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 932				goto out_mds;
 933			pnfs_put_lseg(pgio->pg_lseg);
 934			pgio->pg_lseg = NULL;
 935			/* Sleep for 1 second before retrying */
 936			ssleep(1);
 937			goto retry;
 938		}
 939		pgm = &pgio->pg_mirrors[i];
 940		mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
 941		pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
 942	}
 943
 
 
 
 
 
 
 
 944	return;
 945
 946out_mds:
 947	pnfs_put_lseg(pgio->pg_lseg);
 948	pgio->pg_lseg = NULL;
 
 
 
 949	nfs_pageio_reset_write_mds(pgio);
 
 950}
 951
 952static unsigned int
 953ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
 954				    struct nfs_page *req)
 955{
 956	if (!pgio->pg_lseg) {
 957		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 958						   req->wb_context,
 959						   0,
 960						   NFS4_MAX_UINT64,
 961						   IOMODE_RW,
 962						   false,
 963						   GFP_NOFS);
 964		if (IS_ERR(pgio->pg_lseg)) {
 965			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 966			pgio->pg_lseg = NULL;
 967			goto out;
 968		}
 969	}
 970	if (pgio->pg_lseg)
 971		return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
 972
 
 
 
 
 973	/* no lseg means that pnfs is not in use, so no mirroring here */
 974	nfs_pageio_reset_write_mds(pgio);
 975out:
 976	return 1;
 977}
 978
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 979static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
 980	.pg_init = ff_layout_pg_init_read,
 981	.pg_test = pnfs_generic_pg_test,
 982	.pg_doio = pnfs_generic_pg_readpages,
 983	.pg_cleanup = pnfs_generic_pg_cleanup,
 984};
 985
 986static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
 987	.pg_init = ff_layout_pg_init_write,
 988	.pg_test = pnfs_generic_pg_test,
 989	.pg_doio = pnfs_generic_pg_writepages,
 990	.pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
 991	.pg_cleanup = pnfs_generic_pg_cleanup,
 
 
 992};
 993
 994static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
 995{
 996	struct rpc_task *task = &hdr->task;
 997
 998	pnfs_layoutcommit_inode(hdr->inode, false);
 999
1000	if (retry_pnfs) {
1001		dprintk("%s Reset task %5u for i/o through pNFS "
1002			"(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1003			hdr->task.tk_pid,
1004			hdr->inode->i_sb->s_id,
1005			(unsigned long long)NFS_FILEID(hdr->inode),
1006			hdr->args.count,
1007			(unsigned long long)hdr->args.offset);
1008
1009		hdr->completion_ops->reschedule_io(hdr);
1010		return;
1011	}
1012
1013	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1014		dprintk("%s Reset task %5u for i/o through MDS "
1015			"(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1016			hdr->task.tk_pid,
1017			hdr->inode->i_sb->s_id,
1018			(unsigned long long)NFS_FILEID(hdr->inode),
1019			hdr->args.count,
1020			(unsigned long long)hdr->args.offset);
1021
 
 
 
 
1022		task->tk_status = pnfs_write_done_resend_to_mds(hdr);
1023	}
1024}
1025
 
 
 
 
 
 
 
 
 
 
 
 
1026static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
1027{
1028	struct rpc_task *task = &hdr->task;
1029
1030	pnfs_layoutcommit_inode(hdr->inode, false);
 
1031
1032	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1033		dprintk("%s Reset task %5u for i/o through MDS "
1034			"(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1035			hdr->task.tk_pid,
1036			hdr->inode->i_sb->s_id,
1037			(unsigned long long)NFS_FILEID(hdr->inode),
1038			hdr->args.count,
1039			(unsigned long long)hdr->args.offset);
1040
 
 
 
 
1041		task->tk_status = pnfs_read_done_resend_to_mds(hdr);
1042	}
1043}
1044
1045static int ff_layout_async_handle_error_v4(struct rpc_task *task,
1046					   struct nfs4_state *state,
1047					   struct nfs_client *clp,
1048					   struct pnfs_layout_segment *lseg,
1049					   int idx)
1050{
1051	struct pnfs_layout_hdr *lo = lseg->pls_layout;
1052	struct inode *inode = lo->plh_inode;
1053	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1054	struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
1055
1056	switch (task->tk_status) {
1057	case -NFS4ERR_BADSESSION:
1058	case -NFS4ERR_BADSLOT:
1059	case -NFS4ERR_BAD_HIGH_SLOT:
1060	case -NFS4ERR_DEADSESSION:
1061	case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1062	case -NFS4ERR_SEQ_FALSE_RETRY:
1063	case -NFS4ERR_SEQ_MISORDERED:
1064		dprintk("%s ERROR %d, Reset session. Exchangeid "
1065			"flags 0x%x\n", __func__, task->tk_status,
1066			clp->cl_exchange_flags);
1067		nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
1068		break;
1069	case -NFS4ERR_DELAY:
1070	case -NFS4ERR_GRACE:
1071		rpc_delay(task, FF_LAYOUT_POLL_RETRY_MAX);
1072		break;
1073	case -NFS4ERR_RETRY_UNCACHED_REP:
1074		break;
1075	/* Invalidate Layout errors */
1076	case -NFS4ERR_PNFS_NO_LAYOUT:
1077	case -ESTALE:           /* mapped NFS4ERR_STALE */
1078	case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
1079	case -EISDIR:           /* mapped NFS4ERR_ISDIR */
1080	case -NFS4ERR_FHEXPIRED:
1081	case -NFS4ERR_WRONG_TYPE:
1082		dprintk("%s Invalid layout error %d\n", __func__,
1083			task->tk_status);
1084		/*
1085		 * Destroy layout so new i/o will get a new layout.
1086		 * Layout will not be destroyed until all current lseg
1087		 * references are put. Mark layout as invalid to resend failed
1088		 * i/o and all i/o waiting on the slot table to the MDS until
1089		 * layout is destroyed and a new valid layout is obtained.
1090		 */
1091		pnfs_destroy_layout(NFS_I(inode));
1092		rpc_wake_up(&tbl->slot_tbl_waitq);
1093		goto reset;
1094	/* RPC connection errors */
1095	case -ECONNREFUSED:
1096	case -EHOSTDOWN:
1097	case -EHOSTUNREACH:
1098	case -ENETUNREACH:
1099	case -EIO:
1100	case -ETIMEDOUT:
1101	case -EPIPE:
 
 
1102		dprintk("%s DS connection error %d\n", __func__,
1103			task->tk_status);
1104		nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1105				&devid->deviceid);
1106		rpc_wake_up(&tbl->slot_tbl_waitq);
1107		/* fall through */
1108	default:
1109		if (ff_layout_avoid_mds_available_ds(lseg))
1110			return -NFS4ERR_RESET_TO_PNFS;
1111reset:
1112		dprintk("%s Retry through MDS. Error %d\n", __func__,
1113			task->tk_status);
1114		return -NFS4ERR_RESET_TO_MDS;
1115	}
1116	task->tk_status = 0;
1117	return -EAGAIN;
1118}
1119
1120/* Retry all errors through either pNFS or MDS except for -EJUKEBOX */
1121static int ff_layout_async_handle_error_v3(struct rpc_task *task,
1122					   struct pnfs_layout_segment *lseg,
1123					   int idx)
1124{
1125	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1126
1127	switch (task->tk_status) {
1128	/* File access problems. Don't mark the device as unavailable */
1129	case -EACCES:
1130	case -ESTALE:
1131	case -EISDIR:
1132	case -EBADHANDLE:
1133	case -ELOOP:
1134	case -ENOSPC:
1135		break;
1136	case -EJUKEBOX:
1137		nfs_inc_stats(lseg->pls_layout->plh_inode, NFSIOS_DELAY);
1138		goto out_retry;
1139	default:
1140		dprintk("%s DS connection error %d\n", __func__,
1141			task->tk_status);
1142		nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1143				&devid->deviceid);
1144	}
1145	/* FIXME: Need to prevent infinite looping here. */
1146	return -NFS4ERR_RESET_TO_PNFS;
1147out_retry:
1148	task->tk_status = 0;
1149	rpc_restart_call_prepare(task);
1150	rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
1151	return -EAGAIN;
1152}
1153
1154static int ff_layout_async_handle_error(struct rpc_task *task,
1155					struct nfs4_state *state,
1156					struct nfs_client *clp,
1157					struct pnfs_layout_segment *lseg,
1158					int idx)
1159{
1160	int vers = clp->cl_nfs_mod->rpc_vers->number;
1161
1162	if (task->tk_status >= 0)
 
1163		return 0;
 
1164
1165	/* Handle the case of an invalid layout segment */
1166	if (!pnfs_is_valid_lseg(lseg))
1167		return -NFS4ERR_RESET_TO_PNFS;
1168
1169	switch (vers) {
1170	case 3:
1171		return ff_layout_async_handle_error_v3(task, lseg, idx);
1172	case 4:
1173		return ff_layout_async_handle_error_v4(task, state, clp,
1174						       lseg, idx);
1175	default:
1176		/* should never happen */
1177		WARN_ON_ONCE(1);
1178		return 0;
1179	}
1180}
1181
1182static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
1183					int idx, u64 offset, u64 length,
1184					u32 status, int opnum, int error)
1185{
1186	struct nfs4_ff_layout_mirror *mirror;
 
1187	int err;
1188
1189	if (status == 0) {
1190		switch (error) {
1191		case -ETIMEDOUT:
1192		case -EPFNOSUPPORT:
1193		case -EPROTONOSUPPORT:
1194		case -EOPNOTSUPP:
1195		case -ECONNREFUSED:
1196		case -ECONNRESET:
1197		case -EHOSTDOWN:
1198		case -EHOSTUNREACH:
1199		case -ENETUNREACH:
1200		case -EADDRINUSE:
1201		case -ENOBUFS:
1202		case -EPIPE:
1203		case -EPERM:
1204			status = NFS4ERR_NXIO;
 
 
1205			break;
1206		case -EACCES:
1207			status = NFS4ERR_ACCESS;
1208			break;
1209		default:
1210			return;
1211		}
1212	}
1213
 
 
 
 
 
1214	switch (status) {
1215	case NFS4ERR_DELAY:
1216	case NFS4ERR_GRACE:
1217		return;
1218	default:
1219		break;
 
 
 
 
 
 
 
 
 
 
 
 
1220	}
1221
1222	mirror = FF_LAYOUT_COMP(lseg, idx);
1223	err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
1224				       mirror, offset, length, status, opnum,
1225				       GFP_NOIO);
1226	pnfs_error_mark_layout_for_return(lseg->pls_layout->plh_inode, lseg);
1227	dprintk("%s: err %d op %d status %u\n", __func__, err, opnum, status);
1228}
1229
1230/* NFS_PROTO call done callback routines */
1231static int ff_layout_read_done_cb(struct rpc_task *task,
1232				struct nfs_pgio_header *hdr)
1233{
1234	int err;
1235
1236	trace_nfs4_pnfs_read(hdr, task->tk_status);
1237	if (task->tk_status < 0)
1238		ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1239					    hdr->args.offset, hdr->args.count,
1240					    hdr->res.op_status, OP_READ,
1241					    task->tk_status);
 
 
 
1242	err = ff_layout_async_handle_error(task, hdr->args.context->state,
1243					   hdr->ds_clp, hdr->lseg,
1244					   hdr->pgio_mirror_idx);
1245
 
 
 
1246	switch (err) {
1247	case -NFS4ERR_RESET_TO_PNFS:
1248		if (ff_layout_choose_best_ds_for_read(hdr->lseg,
1249					hdr->pgio_mirror_idx + 1,
1250					&hdr->pgio_mirror_idx))
1251			goto out_eagain;
1252		ff_layout_read_record_layoutstats_done(task, hdr);
1253		pnfs_read_resend_pnfs(hdr);
1254		return task->tk_status;
1255	case -NFS4ERR_RESET_TO_MDS:
1256		ff_layout_reset_read(hdr);
1257		return task->tk_status;
1258	case -EAGAIN:
1259		goto out_eagain;
1260	}
1261
1262	return 0;
1263out_eagain:
1264	rpc_restart_call_prepare(task);
1265	return -EAGAIN;
1266}
1267
1268static bool
1269ff_layout_need_layoutcommit(struct pnfs_layout_segment *lseg)
1270{
1271	return !(FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_LAYOUTCOMMIT);
1272}
1273
1274/*
1275 * We reference the rpc_cred of the first WRITE that triggers the need for
1276 * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
1277 * rfc5661 is not clear about which credential should be used.
1278 *
1279 * Flexlayout client should treat DS replied FILE_SYNC as DATA_SYNC, so
1280 * to follow http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
1281 * we always send layoutcommit after DS writes.
1282 */
1283static void
1284ff_layout_set_layoutcommit(struct inode *inode,
1285		struct pnfs_layout_segment *lseg,
1286		loff_t end_offset)
1287{
1288	if (!ff_layout_need_layoutcommit(lseg))
1289		return;
1290
1291	pnfs_set_layoutcommit(inode, lseg, end_offset);
1292	dprintk("%s inode %lu pls_end_pos %llu\n", __func__, inode->i_ino,
1293		(unsigned long long) NFS_I(inode)->layout->plh_lwb);
1294}
1295
1296static bool
1297ff_layout_device_unavailable(struct pnfs_layout_segment *lseg, int idx)
1298{
1299	/* No mirroring for now */
1300	struct nfs4_deviceid_node *node = FF_LAYOUT_DEVID_NODE(lseg, idx);
1301
1302	return ff_layout_test_devid_unavailable(node);
1303}
1304
1305static void ff_layout_read_record_layoutstats_start(struct rpc_task *task,
1306		struct nfs_pgio_header *hdr)
1307{
1308	if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1309		return;
1310	nfs4_ff_layout_stat_io_start_read(hdr->inode,
1311			FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1312			hdr->args.count,
1313			task->tk_start);
1314}
1315
1316static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
1317		struct nfs_pgio_header *hdr)
1318{
1319	if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1320		return;
1321	nfs4_ff_layout_stat_io_end_read(task,
1322			FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1323			hdr->args.count,
1324			hdr->res.count);
 
1325}
1326
1327static int ff_layout_read_prepare_common(struct rpc_task *task,
1328					 struct nfs_pgio_header *hdr)
1329{
1330	if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1331		rpc_exit(task, -EIO);
1332		return -EIO;
1333	}
1334	if (ff_layout_device_unavailable(hdr->lseg, hdr->pgio_mirror_idx)) {
1335		rpc_exit(task, -EHOSTDOWN);
 
1336		return -EAGAIN;
1337	}
1338
1339	ff_layout_read_record_layoutstats_start(task, hdr);
1340	return 0;
1341}
1342
1343/*
1344 * Call ops for the async read/write cases
1345 * In the case of dense layouts, the offset needs to be reset to its
1346 * original value.
1347 */
1348static void ff_layout_read_prepare_v3(struct rpc_task *task, void *data)
1349{
1350	struct nfs_pgio_header *hdr = data;
1351
1352	if (ff_layout_read_prepare_common(task, hdr))
1353		return;
1354
1355	rpc_call_start(task);
1356}
1357
1358static void ff_layout_read_prepare_v4(struct rpc_task *task, void *data)
1359{
1360	struct nfs_pgio_header *hdr = data;
1361
1362	if (nfs4_setup_sequence(hdr->ds_clp,
1363				&hdr->args.seq_args,
1364				&hdr->res.seq_res,
1365				task))
1366		return;
1367
1368	if (ff_layout_read_prepare_common(task, hdr))
1369		return;
1370
1371	if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
1372			hdr->args.lock_context, FMODE_READ) == -EIO)
1373		rpc_exit(task, -EIO); /* lost lock, terminate I/O */
1374}
1375
1376static void ff_layout_read_call_done(struct rpc_task *task, void *data)
1377{
1378	struct nfs_pgio_header *hdr = data;
1379
1380	dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
1381
1382	if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1383	    task->tk_status == 0) {
1384		nfs4_sequence_done(task, &hdr->res.seq_res);
1385		return;
1386	}
1387
1388	/* Note this may cause RPC to be resent */
1389	hdr->mds_ops->rpc_call_done(task, hdr);
1390}
1391
1392static void ff_layout_read_count_stats(struct rpc_task *task, void *data)
1393{
1394	struct nfs_pgio_header *hdr = data;
1395
1396	ff_layout_read_record_layoutstats_done(task, hdr);
1397	rpc_count_iostats_metrics(task,
1398	    &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_READ]);
1399}
1400
1401static void ff_layout_read_release(void *data)
1402{
1403	struct nfs_pgio_header *hdr = data;
1404
1405	ff_layout_read_record_layoutstats_done(&hdr->task, hdr);
 
 
 
 
1406	pnfs_generic_rw_release(data);
1407}
1408
1409
1410static int ff_layout_write_done_cb(struct rpc_task *task,
1411				struct nfs_pgio_header *hdr)
1412{
1413	loff_t end_offs = 0;
1414	int err;
1415
1416	trace_nfs4_pnfs_write(hdr, task->tk_status);
1417	if (task->tk_status < 0)
1418		ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1419					    hdr->args.offset, hdr->args.count,
1420					    hdr->res.op_status, OP_WRITE,
1421					    task->tk_status);
 
 
 
1422	err = ff_layout_async_handle_error(task, hdr->args.context->state,
1423					   hdr->ds_clp, hdr->lseg,
1424					   hdr->pgio_mirror_idx);
1425
 
 
 
1426	switch (err) {
1427	case -NFS4ERR_RESET_TO_PNFS:
1428		ff_layout_reset_write(hdr, true);
1429		return task->tk_status;
1430	case -NFS4ERR_RESET_TO_MDS:
1431		ff_layout_reset_write(hdr, false);
1432		return task->tk_status;
1433	case -EAGAIN:
1434		return -EAGAIN;
1435	}
1436
1437	if (hdr->res.verf->committed == NFS_FILE_SYNC ||
1438	    hdr->res.verf->committed == NFS_DATA_SYNC)
1439		end_offs = hdr->mds_offset + (loff_t)hdr->res.count;
1440
1441	/* Note: if the write is unstable, don't set end_offs until commit */
1442	ff_layout_set_layoutcommit(hdr->inode, hdr->lseg, end_offs);
1443
1444	/* zero out fattr since we don't care DS attr at all */
1445	hdr->fattr.valid = 0;
1446	if (task->tk_status >= 0)
1447		nfs_writeback_update_inode(hdr);
1448
1449	return 0;
1450}
1451
1452static int ff_layout_commit_done_cb(struct rpc_task *task,
1453				     struct nfs_commit_data *data)
1454{
1455	int err;
1456
1457	trace_nfs4_pnfs_commit_ds(data, task->tk_status);
1458	if (task->tk_status < 0)
1459		ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
1460					    data->args.offset, data->args.count,
1461					    data->res.op_status, OP_COMMIT,
1462					    task->tk_status);
 
 
 
1463	err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
1464					   data->lseg, data->ds_commit_index);
1465
 
1466	switch (err) {
1467	case -NFS4ERR_RESET_TO_PNFS:
1468		pnfs_generic_prepare_to_resend_writes(data);
1469		return -EAGAIN;
1470	case -NFS4ERR_RESET_TO_MDS:
1471		pnfs_generic_prepare_to_resend_writes(data);
1472		return -EAGAIN;
1473	case -EAGAIN:
1474		rpc_restart_call_prepare(task);
1475		return -EAGAIN;
1476	}
1477
1478	ff_layout_set_layoutcommit(data->inode, data->lseg, data->lwb);
1479
1480	return 0;
1481}
1482
1483static void ff_layout_write_record_layoutstats_start(struct rpc_task *task,
1484		struct nfs_pgio_header *hdr)
1485{
1486	if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1487		return;
1488	nfs4_ff_layout_stat_io_start_write(hdr->inode,
1489			FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1490			hdr->args.count,
1491			task->tk_start);
1492}
1493
1494static void ff_layout_write_record_layoutstats_done(struct rpc_task *task,
1495		struct nfs_pgio_header *hdr)
1496{
1497	if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1498		return;
1499	nfs4_ff_layout_stat_io_end_write(task,
1500			FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1501			hdr->args.count, hdr->res.count,
1502			hdr->res.verf->committed);
 
1503}
1504
1505static int ff_layout_write_prepare_common(struct rpc_task *task,
1506					  struct nfs_pgio_header *hdr)
1507{
1508	if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1509		rpc_exit(task, -EIO);
1510		return -EIO;
1511	}
1512
1513	if (ff_layout_device_unavailable(hdr->lseg, hdr->pgio_mirror_idx)) {
1514		rpc_exit(task, -EHOSTDOWN);
1515		return -EAGAIN;
1516	}
1517
1518	ff_layout_write_record_layoutstats_start(task, hdr);
1519	return 0;
1520}
1521
1522static void ff_layout_write_prepare_v3(struct rpc_task *task, void *data)
1523{
1524	struct nfs_pgio_header *hdr = data;
1525
1526	if (ff_layout_write_prepare_common(task, hdr))
1527		return;
1528
1529	rpc_call_start(task);
1530}
1531
1532static void ff_layout_write_prepare_v4(struct rpc_task *task, void *data)
1533{
1534	struct nfs_pgio_header *hdr = data;
1535
1536	if (nfs4_setup_sequence(hdr->ds_clp,
1537				&hdr->args.seq_args,
1538				&hdr->res.seq_res,
1539				task))
1540		return;
1541
1542	if (ff_layout_write_prepare_common(task, hdr))
1543		return;
1544
1545	if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
1546			hdr->args.lock_context, FMODE_WRITE) == -EIO)
1547		rpc_exit(task, -EIO); /* lost lock, terminate I/O */
1548}
1549
1550static void ff_layout_write_call_done(struct rpc_task *task, void *data)
1551{
1552	struct nfs_pgio_header *hdr = data;
1553
1554	if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1555	    task->tk_status == 0) {
1556		nfs4_sequence_done(task, &hdr->res.seq_res);
1557		return;
1558	}
1559
1560	/* Note this may cause RPC to be resent */
1561	hdr->mds_ops->rpc_call_done(task, hdr);
1562}
1563
1564static void ff_layout_write_count_stats(struct rpc_task *task, void *data)
1565{
1566	struct nfs_pgio_header *hdr = data;
1567
1568	ff_layout_write_record_layoutstats_done(task, hdr);
1569	rpc_count_iostats_metrics(task,
1570	    &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_WRITE]);
1571}
1572
1573static void ff_layout_write_release(void *data)
1574{
1575	struct nfs_pgio_header *hdr = data;
1576
1577	ff_layout_write_record_layoutstats_done(&hdr->task, hdr);
 
 
 
 
 
1578	pnfs_generic_rw_release(data);
1579}
1580
1581static void ff_layout_commit_record_layoutstats_start(struct rpc_task *task,
1582		struct nfs_commit_data *cdata)
1583{
1584	if (test_and_set_bit(NFS_IOHDR_STAT, &cdata->flags))
1585		return;
1586	nfs4_ff_layout_stat_io_start_write(cdata->inode,
1587			FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1588			0, task->tk_start);
1589}
1590
1591static void ff_layout_commit_record_layoutstats_done(struct rpc_task *task,
1592		struct nfs_commit_data *cdata)
1593{
1594	struct nfs_page *req;
1595	__u64 count = 0;
1596
1597	if (!test_and_clear_bit(NFS_IOHDR_STAT, &cdata->flags))
1598		return;
1599
1600	if (task->tk_status == 0) {
1601		list_for_each_entry(req, &cdata->pages, wb_list)
1602			count += req->wb_bytes;
1603	}
1604	nfs4_ff_layout_stat_io_end_write(task,
1605			FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1606			count, count, NFS_FILE_SYNC);
 
1607}
1608
1609static void ff_layout_commit_prepare_common(struct rpc_task *task,
1610		struct nfs_commit_data *cdata)
1611{
 
 
 
 
 
1612	ff_layout_commit_record_layoutstats_start(task, cdata);
 
1613}
1614
1615static void ff_layout_commit_prepare_v3(struct rpc_task *task, void *data)
1616{
1617	ff_layout_commit_prepare_common(task, data);
 
 
1618	rpc_call_start(task);
1619}
1620
1621static void ff_layout_commit_prepare_v4(struct rpc_task *task, void *data)
1622{
1623	struct nfs_commit_data *wdata = data;
1624
1625	if (nfs4_setup_sequence(wdata->ds_clp,
1626				&wdata->args.seq_args,
1627				&wdata->res.seq_res,
1628				task))
1629		return;
1630	ff_layout_commit_prepare_common(task, data);
1631}
1632
1633static void ff_layout_commit_done(struct rpc_task *task, void *data)
1634{
1635	pnfs_generic_write_commit_done(task, data);
1636}
1637
1638static void ff_layout_commit_count_stats(struct rpc_task *task, void *data)
1639{
1640	struct nfs_commit_data *cdata = data;
1641
1642	ff_layout_commit_record_layoutstats_done(task, cdata);
1643	rpc_count_iostats_metrics(task,
1644	    &NFS_CLIENT(cdata->inode)->cl_metrics[NFSPROC4_CLNT_COMMIT]);
1645}
1646
1647static void ff_layout_commit_release(void *data)
1648{
1649	struct nfs_commit_data *cdata = data;
1650
1651	ff_layout_commit_record_layoutstats_done(&cdata->task, cdata);
1652	pnfs_generic_commit_release(data);
1653}
1654
1655static const struct rpc_call_ops ff_layout_read_call_ops_v3 = {
1656	.rpc_call_prepare = ff_layout_read_prepare_v3,
1657	.rpc_call_done = ff_layout_read_call_done,
1658	.rpc_count_stats = ff_layout_read_count_stats,
1659	.rpc_release = ff_layout_read_release,
1660};
1661
1662static const struct rpc_call_ops ff_layout_read_call_ops_v4 = {
1663	.rpc_call_prepare = ff_layout_read_prepare_v4,
1664	.rpc_call_done = ff_layout_read_call_done,
1665	.rpc_count_stats = ff_layout_read_count_stats,
1666	.rpc_release = ff_layout_read_release,
1667};
1668
1669static const struct rpc_call_ops ff_layout_write_call_ops_v3 = {
1670	.rpc_call_prepare = ff_layout_write_prepare_v3,
1671	.rpc_call_done = ff_layout_write_call_done,
1672	.rpc_count_stats = ff_layout_write_count_stats,
1673	.rpc_release = ff_layout_write_release,
1674};
1675
1676static const struct rpc_call_ops ff_layout_write_call_ops_v4 = {
1677	.rpc_call_prepare = ff_layout_write_prepare_v4,
1678	.rpc_call_done = ff_layout_write_call_done,
1679	.rpc_count_stats = ff_layout_write_count_stats,
1680	.rpc_release = ff_layout_write_release,
1681};
1682
1683static const struct rpc_call_ops ff_layout_commit_call_ops_v3 = {
1684	.rpc_call_prepare = ff_layout_commit_prepare_v3,
1685	.rpc_call_done = ff_layout_commit_done,
1686	.rpc_count_stats = ff_layout_commit_count_stats,
1687	.rpc_release = ff_layout_commit_release,
1688};
1689
1690static const struct rpc_call_ops ff_layout_commit_call_ops_v4 = {
1691	.rpc_call_prepare = ff_layout_commit_prepare_v4,
1692	.rpc_call_done = ff_layout_commit_done,
1693	.rpc_count_stats = ff_layout_commit_count_stats,
1694	.rpc_release = ff_layout_commit_release,
1695};
1696
1697static enum pnfs_try_status
1698ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
1699{
1700	struct pnfs_layout_segment *lseg = hdr->lseg;
1701	struct nfs4_pnfs_ds *ds;
1702	struct rpc_clnt *ds_clnt;
1703	struct rpc_cred *ds_cred;
 
1704	loff_t offset = hdr->args.offset;
1705	u32 idx = hdr->pgio_mirror_idx;
1706	int vers;
1707	struct nfs_fh *fh;
1708
1709	dprintk("--> %s ino %lu pgbase %u req %zu@%llu\n",
1710		__func__, hdr->inode->i_ino,
1711		hdr->args.pgbase, (size_t)hdr->args.count, offset);
1712
1713	ds = nfs4_ff_layout_prepare_ds(lseg, idx, false);
 
1714	if (!ds)
1715		goto out_failed;
1716
1717	ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1718						   hdr->inode);
1719	if (IS_ERR(ds_clnt))
1720		goto out_failed;
1721
1722	ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
1723	if (!ds_cred)
1724		goto out_failed;
1725
1726	vers = nfs4_ff_layout_ds_version(lseg, idx);
1727
1728	dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
1729		ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count), vers);
1730
1731	hdr->pgio_done_cb = ff_layout_read_done_cb;
1732	refcount_inc(&ds->ds_clp->cl_count);
1733	hdr->ds_clp = ds->ds_clp;
1734	fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
1735	if (fh)
1736		hdr->args.fh = fh;
 
 
 
1737	/*
1738	 * Note that if we ever decide to split across DSes,
1739	 * then we may need to handle dense-like offsets.
1740	 */
1741	hdr->args.offset = offset;
1742	hdr->mds_offset = offset;
1743
1744	/* Perform an asynchronous read to ds */
1745	nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1746			  vers == 3 ? &ff_layout_read_call_ops_v3 :
1747				      &ff_layout_read_call_ops_v4,
1748			  0, RPC_TASK_SOFTCONN);
1749	put_rpccred(ds_cred);
1750	return PNFS_ATTEMPTED;
1751
1752out_failed:
1753	if (ff_layout_avoid_mds_available_ds(lseg))
1754		return PNFS_TRY_AGAIN;
 
 
 
1755	return PNFS_NOT_ATTEMPTED;
1756}
1757
1758/* Perform async writes. */
1759static enum pnfs_try_status
1760ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
1761{
1762	struct pnfs_layout_segment *lseg = hdr->lseg;
1763	struct nfs4_pnfs_ds *ds;
1764	struct rpc_clnt *ds_clnt;
1765	struct rpc_cred *ds_cred;
 
1766	loff_t offset = hdr->args.offset;
1767	int vers;
1768	struct nfs_fh *fh;
1769	int idx = hdr->pgio_mirror_idx;
1770
1771	ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
 
1772	if (!ds)
1773		goto out_failed;
1774
1775	ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1776						   hdr->inode);
1777	if (IS_ERR(ds_clnt))
1778		goto out_failed;
1779
1780	ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
1781	if (!ds_cred)
1782		goto out_failed;
1783
1784	vers = nfs4_ff_layout_ds_version(lseg, idx);
1785
1786	dprintk("%s ino %lu sync %d req %zu@%llu DS: %s cl_count %d vers %d\n",
1787		__func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
1788		offset, ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count),
1789		vers);
1790
1791	hdr->pgio_done_cb = ff_layout_write_done_cb;
1792	refcount_inc(&ds->ds_clp->cl_count);
1793	hdr->ds_clp = ds->ds_clp;
1794	hdr->ds_commit_idx = idx;
1795	fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
1796	if (fh)
1797		hdr->args.fh = fh;
1798
 
 
1799	/*
1800	 * Note that if we ever decide to split across DSes,
1801	 * then we may need to handle dense-like offsets.
1802	 */
1803	hdr->args.offset = offset;
1804
1805	/* Perform an asynchronous write */
1806	nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1807			  vers == 3 ? &ff_layout_write_call_ops_v3 :
1808				      &ff_layout_write_call_ops_v4,
1809			  sync, RPC_TASK_SOFTCONN);
1810	put_rpccred(ds_cred);
1811	return PNFS_ATTEMPTED;
1812
1813out_failed:
1814	if (ff_layout_avoid_mds_available_ds(lseg))
1815		return PNFS_TRY_AGAIN;
 
 
 
1816	return PNFS_NOT_ATTEMPTED;
1817}
1818
1819static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1820{
1821	return i;
1822}
1823
1824static struct nfs_fh *
1825select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1826{
1827	struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1828
1829	/* FIXME: Assume that there is only one NFS version available
1830	 * for the DS.
1831	 */
1832	return &flseg->mirror_array[i]->fh_versions[0];
1833}
1834
1835static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
1836{
1837	struct pnfs_layout_segment *lseg = data->lseg;
1838	struct nfs4_pnfs_ds *ds;
1839	struct rpc_clnt *ds_clnt;
1840	struct rpc_cred *ds_cred;
 
1841	u32 idx;
1842	int vers, ret;
1843	struct nfs_fh *fh;
1844
1845	if (!lseg || !(pnfs_is_valid_lseg(lseg) ||
1846	    test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags)))
1847		goto out_err;
1848
1849	idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1850	ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
 
1851	if (!ds)
1852		goto out_err;
1853
1854	ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1855						   data->inode);
1856	if (IS_ERR(ds_clnt))
1857		goto out_err;
1858
1859	ds_cred = ff_layout_get_ds_cred(lseg, idx, data->cred);
1860	if (!ds_cred)
1861		goto out_err;
1862
1863	vers = nfs4_ff_layout_ds_version(lseg, idx);
1864
1865	dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
1866		data->inode->i_ino, how, refcount_read(&ds->ds_clp->cl_count),
1867		vers);
1868	data->commit_done_cb = ff_layout_commit_done_cb;
1869	data->cred = ds_cred;
1870	refcount_inc(&ds->ds_clp->cl_count);
1871	data->ds_clp = ds->ds_clp;
1872	fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1873	if (fh)
1874		data->args.fh = fh;
1875
1876	ret = nfs_initiate_commit(ds_clnt, data, ds->ds_clp->rpc_ops,
1877				   vers == 3 ? &ff_layout_commit_call_ops_v3 :
1878					       &ff_layout_commit_call_ops_v4,
1879				   how, RPC_TASK_SOFTCONN);
1880	put_rpccred(ds_cred);
1881	return ret;
1882out_err:
1883	pnfs_generic_prepare_to_resend_writes(data);
1884	pnfs_generic_commit_release(data);
1885	return -EAGAIN;
1886}
1887
1888static int
1889ff_layout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1890			   int how, struct nfs_commit_info *cinfo)
1891{
1892	return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1893					    ff_layout_initiate_commit);
1894}
1895
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1896static struct pnfs_ds_commit_info *
1897ff_layout_get_ds_info(struct inode *inode)
1898{
1899	struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1900
1901	if (layout == NULL)
1902		return NULL;
1903
1904	return &FF_LAYOUT_FROM_HDR(layout)->commit_info;
1905}
1906
1907static void
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1908ff_layout_free_deviceid_node(struct nfs4_deviceid_node *d)
1909{
1910	nfs4_ff_layout_free_deviceid(container_of(d, struct nfs4_ff_layout_ds,
1911						  id_node));
1912}
1913
1914static int ff_layout_encode_ioerr(struct xdr_stream *xdr,
1915				  const struct nfs4_layoutreturn_args *args,
1916				  const struct nfs4_flexfile_layoutreturn_args *ff_args)
1917{
1918	__be32 *start;
1919
1920	start = xdr_reserve_space(xdr, 4);
1921	if (unlikely(!start))
1922		return -E2BIG;
1923
1924	*start = cpu_to_be32(ff_args->num_errors);
1925	/* This assume we always return _ALL_ layouts */
1926	return ff_layout_encode_ds_ioerr(xdr, &ff_args->errors);
1927}
1928
1929static void
1930encode_opaque_fixed(struct xdr_stream *xdr, const void *buf, size_t len)
1931{
1932	WARN_ON_ONCE(xdr_stream_encode_opaque_fixed(xdr, buf, len) < 0);
1933}
1934
1935static void
1936ff_layout_encode_ff_iostat_head(struct xdr_stream *xdr,
1937			    const nfs4_stateid *stateid,
1938			    const struct nfs42_layoutstat_devinfo *devinfo)
1939{
1940	__be32 *p;
1941
1942	p = xdr_reserve_space(xdr, 8 + 8);
1943	p = xdr_encode_hyper(p, devinfo->offset);
1944	p = xdr_encode_hyper(p, devinfo->length);
1945	encode_opaque_fixed(xdr, stateid->data, NFS4_STATEID_SIZE);
1946	p = xdr_reserve_space(xdr, 4*8);
1947	p = xdr_encode_hyper(p, devinfo->read_count);
1948	p = xdr_encode_hyper(p, devinfo->read_bytes);
1949	p = xdr_encode_hyper(p, devinfo->write_count);
1950	p = xdr_encode_hyper(p, devinfo->write_bytes);
1951	encode_opaque_fixed(xdr, devinfo->dev_id.data, NFS4_DEVICEID4_SIZE);
1952}
1953
1954static void
1955ff_layout_encode_ff_iostat(struct xdr_stream *xdr,
1956			    const nfs4_stateid *stateid,
1957			    const struct nfs42_layoutstat_devinfo *devinfo)
1958{
1959	ff_layout_encode_ff_iostat_head(xdr, stateid, devinfo);
1960	ff_layout_encode_ff_layoutupdate(xdr, devinfo,
1961			devinfo->ld_private.data);
1962}
1963
1964/* report nothing for now */
1965static void ff_layout_encode_iostats_array(struct xdr_stream *xdr,
1966		const struct nfs4_layoutreturn_args *args,
1967		struct nfs4_flexfile_layoutreturn_args *ff_args)
1968{
1969	__be32 *p;
1970	int i;
1971
1972	p = xdr_reserve_space(xdr, 4);
1973	*p = cpu_to_be32(ff_args->num_dev);
1974	for (i = 0; i < ff_args->num_dev; i++)
1975		ff_layout_encode_ff_iostat(xdr,
1976				&args->layout->plh_stateid,
1977				&ff_args->devinfo[i]);
1978}
1979
1980static void
1981ff_layout_free_iostats_array(struct nfs42_layoutstat_devinfo *devinfo,
1982		unsigned int num_entries)
1983{
1984	unsigned int i;
1985
1986	for (i = 0; i < num_entries; i++) {
1987		if (!devinfo[i].ld_private.ops)
1988			continue;
1989		if (!devinfo[i].ld_private.ops->free)
1990			continue;
1991		devinfo[i].ld_private.ops->free(&devinfo[i].ld_private);
1992	}
1993}
1994
1995static struct nfs4_deviceid_node *
1996ff_layout_alloc_deviceid_node(struct nfs_server *server,
1997			      struct pnfs_device *pdev, gfp_t gfp_flags)
1998{
1999	struct nfs4_ff_layout_ds *dsaddr;
2000
2001	dsaddr = nfs4_ff_alloc_deviceid_node(server, pdev, gfp_flags);
2002	if (!dsaddr)
2003		return NULL;
2004	return &dsaddr->id_node;
2005}
2006
2007static void
2008ff_layout_encode_layoutreturn(struct xdr_stream *xdr,
2009		const void *voidargs,
2010		const struct nfs4_xdr_opaque_data *ff_opaque)
2011{
2012	const struct nfs4_layoutreturn_args *args = voidargs;
2013	struct nfs4_flexfile_layoutreturn_args *ff_args = ff_opaque->data;
2014	struct xdr_buf tmp_buf = {
2015		.head = {
2016			[0] = {
2017				.iov_base = page_address(ff_args->pages[0]),
2018			},
2019		},
2020		.buflen = PAGE_SIZE,
2021	};
2022	struct xdr_stream tmp_xdr;
2023	__be32 *start;
2024
2025	dprintk("%s: Begin\n", __func__);
2026
2027	xdr_init_encode(&tmp_xdr, &tmp_buf, NULL);
2028
2029	ff_layout_encode_ioerr(&tmp_xdr, args, ff_args);
2030	ff_layout_encode_iostats_array(&tmp_xdr, args, ff_args);
2031
2032	start = xdr_reserve_space(xdr, 4);
2033	*start = cpu_to_be32(tmp_buf.len);
2034	xdr_write_pages(xdr, ff_args->pages, 0, tmp_buf.len);
2035
2036	dprintk("%s: Return\n", __func__);
2037}
2038
2039static void
2040ff_layout_free_layoutreturn(struct nfs4_xdr_opaque_data *args)
2041{
2042	struct nfs4_flexfile_layoutreturn_args *ff_args;
2043
2044	if (!args->data)
2045		return;
2046	ff_args = args->data;
2047	args->data = NULL;
2048
2049	ff_layout_free_ds_ioerr(&ff_args->errors);
2050	ff_layout_free_iostats_array(ff_args->devinfo, ff_args->num_dev);
2051
2052	put_page(ff_args->pages[0]);
2053	kfree(ff_args);
2054}
2055
2056static const struct nfs4_xdr_opaque_ops layoutreturn_ops = {
2057	.encode = ff_layout_encode_layoutreturn,
2058	.free = ff_layout_free_layoutreturn,
2059};
2060
2061static int
2062ff_layout_prepare_layoutreturn(struct nfs4_layoutreturn_args *args)
2063{
2064	struct nfs4_flexfile_layoutreturn_args *ff_args;
2065	struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(args->layout);
2066
2067	ff_args = kmalloc(sizeof(*ff_args), GFP_KERNEL);
2068	if (!ff_args)
2069		goto out_nomem;
2070	ff_args->pages[0] = alloc_page(GFP_KERNEL);
2071	if (!ff_args->pages[0])
2072		goto out_nomem_free;
2073
2074	INIT_LIST_HEAD(&ff_args->errors);
2075	ff_args->num_errors = ff_layout_fetch_ds_ioerr(args->layout,
2076			&args->range, &ff_args->errors,
2077			FF_LAYOUTRETURN_MAXERR);
2078
2079	spin_lock(&args->inode->i_lock);
2080	ff_args->num_dev = ff_layout_mirror_prepare_stats(&ff_layout->generic_hdr,
2081			&ff_args->devinfo[0], ARRAY_SIZE(ff_args->devinfo));
 
2082	spin_unlock(&args->inode->i_lock);
2083
2084	args->ld_private->ops = &layoutreturn_ops;
2085	args->ld_private->data = ff_args;
2086	return 0;
2087out_nomem_free:
2088	kfree(ff_args);
2089out_nomem:
2090	return -ENOMEM;
2091}
2092
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2093static int
2094ff_layout_ntop4(const struct sockaddr *sap, char *buf, const size_t buflen)
2095{
2096	const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
2097
2098	return snprintf(buf, buflen, "%pI4", &sin->sin_addr);
2099}
2100
2101static size_t
2102ff_layout_ntop6_noscopeid(const struct sockaddr *sap, char *buf,
2103			  const int buflen)
2104{
2105	const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
2106	const struct in6_addr *addr = &sin6->sin6_addr;
2107
2108	/*
2109	 * RFC 4291, Section 2.2.2
2110	 *
2111	 * Shorthanded ANY address
2112	 */
2113	if (ipv6_addr_any(addr))
2114		return snprintf(buf, buflen, "::");
2115
2116	/*
2117	 * RFC 4291, Section 2.2.2
2118	 *
2119	 * Shorthanded loopback address
2120	 */
2121	if (ipv6_addr_loopback(addr))
2122		return snprintf(buf, buflen, "::1");
2123
2124	/*
2125	 * RFC 4291, Section 2.2.3
2126	 *
2127	 * Special presentation address format for mapped v4
2128	 * addresses.
2129	 */
2130	if (ipv6_addr_v4mapped(addr))
2131		return snprintf(buf, buflen, "::ffff:%pI4",
2132					&addr->s6_addr32[3]);
2133
2134	/*
2135	 * RFC 4291, Section 2.2.1
2136	 */
2137	return snprintf(buf, buflen, "%pI6c", addr);
2138}
2139
2140/* Derived from rpc_sockaddr2uaddr */
2141static void
2142ff_layout_encode_netaddr(struct xdr_stream *xdr, struct nfs4_pnfs_ds_addr *da)
2143{
2144	struct sockaddr *sap = (struct sockaddr *)&da->da_addr;
2145	char portbuf[RPCBIND_MAXUADDRPLEN];
2146	char addrbuf[RPCBIND_MAXUADDRLEN];
2147	char *netid;
2148	unsigned short port;
2149	int len, netid_len;
2150	__be32 *p;
2151
2152	switch (sap->sa_family) {
2153	case AF_INET:
2154		if (ff_layout_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)
2155			return;
2156		port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2157		netid = "tcp";
2158		netid_len = 3;
2159		break;
2160	case AF_INET6:
2161		if (ff_layout_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)
2162			return;
2163		port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
2164		netid = "tcp6";
2165		netid_len = 4;
2166		break;
2167	default:
2168		/* we only support tcp and tcp6 */
2169		WARN_ON_ONCE(1);
2170		return;
2171	}
2172
2173	snprintf(portbuf, sizeof(portbuf), ".%u.%u", port >> 8, port & 0xff);
2174	len = strlcat(addrbuf, portbuf, sizeof(addrbuf));
2175
 
2176	p = xdr_reserve_space(xdr, 4 + netid_len);
2177	xdr_encode_opaque(p, netid, netid_len);
2178
2179	p = xdr_reserve_space(xdr, 4 + len);
2180	xdr_encode_opaque(p, addrbuf, len);
2181}
2182
2183static void
2184ff_layout_encode_nfstime(struct xdr_stream *xdr,
2185			 ktime_t t)
2186{
2187	struct timespec64 ts;
2188	__be32 *p;
2189
2190	p = xdr_reserve_space(xdr, 12);
2191	ts = ktime_to_timespec64(t);
2192	p = xdr_encode_hyper(p, ts.tv_sec);
2193	*p++ = cpu_to_be32(ts.tv_nsec);
2194}
2195
2196static void
2197ff_layout_encode_io_latency(struct xdr_stream *xdr,
2198			    struct nfs4_ff_io_stat *stat)
2199{
2200	__be32 *p;
2201
2202	p = xdr_reserve_space(xdr, 5 * 8);
2203	p = xdr_encode_hyper(p, stat->ops_requested);
2204	p = xdr_encode_hyper(p, stat->bytes_requested);
2205	p = xdr_encode_hyper(p, stat->ops_completed);
2206	p = xdr_encode_hyper(p, stat->bytes_completed);
2207	p = xdr_encode_hyper(p, stat->bytes_not_delivered);
2208	ff_layout_encode_nfstime(xdr, stat->total_busy_time);
2209	ff_layout_encode_nfstime(xdr, stat->aggregate_completion_time);
2210}
2211
2212static void
2213ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
2214			      const struct nfs42_layoutstat_devinfo *devinfo,
2215			      struct nfs4_ff_layout_mirror *mirror)
2216{
2217	struct nfs4_pnfs_ds_addr *da;
2218	struct nfs4_pnfs_ds *ds = mirror->mirror_ds->ds;
2219	struct nfs_fh *fh = &mirror->fh_versions[0];
2220	__be32 *p;
2221
2222	da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
2223	dprintk("%s: DS %s: encoding address %s\n",
2224		__func__, ds->ds_remotestr, da->da_remotestr);
2225	/* netaddr4 */
2226	ff_layout_encode_netaddr(xdr, da);
2227	/* nfs_fh4 */
2228	p = xdr_reserve_space(xdr, 4 + fh->size);
2229	xdr_encode_opaque(p, fh->data, fh->size);
2230	/* ff_io_latency4 read */
2231	spin_lock(&mirror->lock);
2232	ff_layout_encode_io_latency(xdr, &mirror->read_stat.io_stat);
2233	/* ff_io_latency4 write */
2234	ff_layout_encode_io_latency(xdr, &mirror->write_stat.io_stat);
2235	spin_unlock(&mirror->lock);
2236	/* nfstime4 */
2237	ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->start_time));
2238	/* bool */
2239	p = xdr_reserve_space(xdr, 4);
2240	*p = cpu_to_be32(false);
2241}
2242
2243static void
2244ff_layout_encode_layoutstats(struct xdr_stream *xdr, const void *args,
2245			     const struct nfs4_xdr_opaque_data *opaque)
2246{
2247	struct nfs42_layoutstat_devinfo *devinfo = container_of(opaque,
2248			struct nfs42_layoutstat_devinfo, ld_private);
2249	__be32 *start;
2250
2251	/* layoutupdate length */
2252	start = xdr_reserve_space(xdr, 4);
2253	ff_layout_encode_ff_layoutupdate(xdr, devinfo, opaque->data);
2254
2255	*start = cpu_to_be32((xdr->p - start - 1) * 4);
2256}
2257
2258static void
2259ff_layout_free_layoutstats(struct nfs4_xdr_opaque_data *opaque)
2260{
2261	struct nfs4_ff_layout_mirror *mirror = opaque->data;
2262
2263	ff_layout_put_mirror(mirror);
2264}
2265
2266static const struct nfs4_xdr_opaque_ops layoutstat_ops = {
2267	.encode = ff_layout_encode_layoutstats,
2268	.free	= ff_layout_free_layoutstats,
2269};
2270
2271static int
2272ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
2273			       struct nfs42_layoutstat_devinfo *devinfo,
2274			       int dev_limit)
2275{
2276	struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
2277	struct nfs4_ff_layout_mirror *mirror;
2278	struct nfs4_deviceid_node *dev;
2279	int i = 0;
2280
2281	list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
2282		if (i >= dev_limit)
2283			break;
2284		if (IS_ERR_OR_NULL(mirror->mirror_ds))
2285			continue;
2286		if (!test_and_clear_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags))
 
 
2287			continue;
2288		/* mirror refcount put in cleanup_layoutstats */
2289		if (!refcount_inc_not_zero(&mirror->ref))
2290			continue;
2291		dev = &mirror->mirror_ds->id_node; 
2292		memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
2293		devinfo->offset = 0;
2294		devinfo->length = NFS4_MAX_UINT64;
2295		spin_lock(&mirror->lock);
2296		devinfo->read_count = mirror->read_stat.io_stat.ops_completed;
2297		devinfo->read_bytes = mirror->read_stat.io_stat.bytes_completed;
2298		devinfo->write_count = mirror->write_stat.io_stat.ops_completed;
2299		devinfo->write_bytes = mirror->write_stat.io_stat.bytes_completed;
2300		spin_unlock(&mirror->lock);
2301		devinfo->layout_type = LAYOUT_FLEX_FILES;
2302		devinfo->ld_private.ops = &layoutstat_ops;
2303		devinfo->ld_private.data = mirror;
2304
2305		devinfo++;
2306		i++;
2307	}
2308	return i;
2309}
2310
2311static int
2312ff_layout_prepare_layoutstats(struct nfs42_layoutstat_args *args)
2313{
2314	struct nfs4_flexfile_layout *ff_layout;
2315	const int dev_count = PNFS_LAYOUTSTATS_MAXDEV;
2316
2317	/* For now, send at most PNFS_LAYOUTSTATS_MAXDEV statistics */
2318	args->devinfo = kmalloc_array(dev_count, sizeof(*args->devinfo), GFP_NOIO);
 
2319	if (!args->devinfo)
2320		return -ENOMEM;
2321
2322	spin_lock(&args->inode->i_lock);
2323	ff_layout = FF_LAYOUT_FROM_HDR(NFS_I(args->inode)->layout);
2324	args->num_dev = ff_layout_mirror_prepare_stats(&ff_layout->generic_hdr,
2325			&args->devinfo[0], dev_count);
 
 
2326	spin_unlock(&args->inode->i_lock);
2327	if (!args->num_dev) {
2328		kfree(args->devinfo);
2329		args->devinfo = NULL;
2330		return -ENOENT;
2331	}
2332
2333	return 0;
2334}
2335
2336static int
2337ff_layout_set_layoutdriver(struct nfs_server *server,
2338		const struct nfs_fh *dummy)
2339{
2340#if IS_ENABLED(CONFIG_NFS_V4_2)
2341	server->caps |= NFS_CAP_LAYOUTSTATS;
2342#endif
2343	return 0;
2344}
2345
 
 
 
 
 
 
 
 
 
 
2346static struct pnfs_layoutdriver_type flexfilelayout_type = {
2347	.id			= LAYOUT_FLEX_FILES,
2348	.name			= "LAYOUT_FLEX_FILES",
2349	.owner			= THIS_MODULE,
 
 
2350	.set_layoutdriver	= ff_layout_set_layoutdriver,
2351	.alloc_layout_hdr	= ff_layout_alloc_layout_hdr,
2352	.free_layout_hdr	= ff_layout_free_layout_hdr,
2353	.alloc_lseg		= ff_layout_alloc_lseg,
2354	.free_lseg		= ff_layout_free_lseg,
2355	.add_lseg		= ff_layout_add_lseg,
2356	.pg_read_ops		= &ff_layout_pg_read_ops,
2357	.pg_write_ops		= &ff_layout_pg_write_ops,
2358	.get_ds_info		= ff_layout_get_ds_info,
2359	.free_deviceid_node	= ff_layout_free_deviceid_node,
2360	.mark_request_commit	= pnfs_layout_mark_request_commit,
2361	.clear_request_commit	= pnfs_generic_clear_request_commit,
2362	.scan_commit_lists	= pnfs_generic_scan_commit_lists,
2363	.recover_commit_reqs	= pnfs_generic_recover_commit_reqs,
2364	.commit_pagelist	= ff_layout_commit_pagelist,
2365	.read_pagelist		= ff_layout_read_pagelist,
2366	.write_pagelist		= ff_layout_write_pagelist,
2367	.alloc_deviceid_node    = ff_layout_alloc_deviceid_node,
2368	.prepare_layoutreturn   = ff_layout_prepare_layoutreturn,
2369	.sync			= pnfs_nfs_generic_sync,
2370	.prepare_layoutstats	= ff_layout_prepare_layoutstats,
 
2371};
2372
2373static int __init nfs4flexfilelayout_init(void)
2374{
2375	printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Registering...\n",
2376	       __func__);
2377	if (!ff_zero_group) {
2378		ff_zero_group = groups_alloc(0);
2379		if (!ff_zero_group)
2380			return -ENOMEM;
2381	}
2382	return pnfs_register_layoutdriver(&flexfilelayout_type);
2383}
2384
2385static void __exit nfs4flexfilelayout_exit(void)
2386{
2387	printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Unregistering...\n",
2388	       __func__);
2389	pnfs_unregister_layoutdriver(&flexfilelayout_type);
2390	if (ff_zero_group) {
2391		put_group_info(ff_zero_group);
2392		ff_zero_group = NULL;
2393	}
2394}
2395
2396MODULE_ALIAS("nfs-layouttype4-4");
2397
2398MODULE_LICENSE("GPL");
2399MODULE_DESCRIPTION("The NFSv4 flexfile layout driver");
2400
2401module_init(nfs4flexfilelayout_init);
2402module_exit(nfs4flexfilelayout_exit);