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v5.14.15
   1/*
   2 *  pNFS functions to call and manage layout drivers.
   3 *
   4 *  Copyright (c) 2002 [year of first publication]
   5 *  The Regents of the University of Michigan
   6 *  All Rights Reserved
   7 *
   8 *  Dean Hildebrand <dhildebz@umich.edu>
   9 *
  10 *  Permission is granted to use, copy, create derivative works, and
  11 *  redistribute this software and such derivative works for any purpose,
  12 *  so long as the name of the University of Michigan is not used in
  13 *  any advertising or publicity pertaining to the use or distribution
  14 *  of this software without specific, written prior authorization. If
  15 *  the above copyright notice or any other identification of the
  16 *  University of Michigan is included in any copy of any portion of
  17 *  this software, then the disclaimer below must also be included.
  18 *
  19 *  This software is provided as is, without representation or warranty
  20 *  of any kind either express or implied, including without limitation
  21 *  the implied warranties of merchantability, fitness for a particular
  22 *  purpose, or noninfringement.  The Regents of the University of
  23 *  Michigan shall not be liable for any damages, including special,
  24 *  indirect, incidental, or consequential damages, with respect to any
  25 *  claim arising out of or in connection with the use of the software,
  26 *  even if it has been or is hereafter advised of the possibility of
  27 *  such damages.
  28 */
  29
  30#include <linux/nfs_fs.h>
  31#include <linux/nfs_page.h>
  32#include <linux/module.h>
  33#include <linux/sort.h>
  34#include "internal.h"
  35#include "pnfs.h"
  36#include "iostat.h"
  37#include "nfs4trace.h"
  38#include "delegation.h"
  39#include "nfs42.h"
  40#include "nfs4_fs.h"
  41
  42#define NFSDBG_FACILITY		NFSDBG_PNFS
  43#define PNFS_LAYOUTGET_RETRY_TIMEOUT (120*HZ)
  44
  45/* Locking:
  46 *
  47 * pnfs_spinlock:
  48 *      protects pnfs_modules_tbl.
  49 */
  50static DEFINE_SPINLOCK(pnfs_spinlock);
  51
  52/*
  53 * pnfs_modules_tbl holds all pnfs modules
  54 */
  55static LIST_HEAD(pnfs_modules_tbl);
  56
  57static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo);
  58static void pnfs_free_returned_lsegs(struct pnfs_layout_hdr *lo,
  59		struct list_head *free_me,
  60		const struct pnfs_layout_range *range,
  61		u32 seq);
  62static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
  63		                struct list_head *tmp_list);
  64
  65/* Return the registered pnfs layout driver module matching given id */
  66static struct pnfs_layoutdriver_type *
  67find_pnfs_driver_locked(u32 id)
  68{
  69	struct pnfs_layoutdriver_type *local;
  70
  71	list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid)
  72		if (local->id == id)
  73			goto out;
  74	local = NULL;
  75out:
  76	dprintk("%s: Searching for id %u, found %p\n", __func__, id, local);
  77	return local;
  78}
  79
  80static struct pnfs_layoutdriver_type *
  81find_pnfs_driver(u32 id)
  82{
  83	struct pnfs_layoutdriver_type *local;
  84
  85	spin_lock(&pnfs_spinlock);
  86	local = find_pnfs_driver_locked(id);
  87	if (local != NULL && !try_module_get(local->owner)) {
  88		dprintk("%s: Could not grab reference on module\n", __func__);
  89		local = NULL;
  90	}
  91	spin_unlock(&pnfs_spinlock);
  92	return local;
  93}
  94
  95void
  96unset_pnfs_layoutdriver(struct nfs_server *nfss)
  97{
  98	if (nfss->pnfs_curr_ld) {
  99		if (nfss->pnfs_curr_ld->clear_layoutdriver)
 100			nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
 101		/* Decrement the MDS count. Purge the deviceid cache if zero */
 102		if (atomic_dec_and_test(&nfss->nfs_client->cl_mds_count))
 103			nfs4_deviceid_purge_client(nfss->nfs_client);
 104		module_put(nfss->pnfs_curr_ld->owner);
 105	}
 106	nfss->pnfs_curr_ld = NULL;
 107}
 108
 109/*
 110 * When the server sends a list of layout types, we choose one in the order
 111 * given in the list below.
 112 *
 113 * FIXME: should this list be configurable in some fashion? module param?
 114 * 	  mount option? something else?
 115 */
 116static const u32 ld_prefs[] = {
 117	LAYOUT_SCSI,
 118	LAYOUT_BLOCK_VOLUME,
 119	LAYOUT_OSD2_OBJECTS,
 120	LAYOUT_FLEX_FILES,
 121	LAYOUT_NFSV4_1_FILES,
 122	0
 123};
 124
 125static int
 126ld_cmp(const void *e1, const void *e2)
 127{
 128	u32 ld1 = *((u32 *)e1);
 129	u32 ld2 = *((u32 *)e2);
 130	int i;
 131
 132	for (i = 0; ld_prefs[i] != 0; i++) {
 133		if (ld1 == ld_prefs[i])
 134			return -1;
 135
 136		if (ld2 == ld_prefs[i])
 137			return 1;
 138	}
 139	return 0;
 140}
 141
 142/*
 143 * Try to set the server's pnfs module to the pnfs layout type specified by id.
 144 * Currently only one pNFS layout driver per filesystem is supported.
 145 *
 146 * @ids array of layout types supported by MDS.
 147 */
 148void
 149set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
 150		      struct nfs_fsinfo *fsinfo)
 151{
 152	struct pnfs_layoutdriver_type *ld_type = NULL;
 153	u32 id;
 154	int i;
 155
 156	if (fsinfo->nlayouttypes == 0)
 157		goto out_no_driver;
 158	if (!(server->nfs_client->cl_exchange_flags &
 159		 (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
 160		printk(KERN_ERR "NFS: %s: cl_exchange_flags 0x%x\n",
 161			__func__, server->nfs_client->cl_exchange_flags);
 162		goto out_no_driver;
 163	}
 164
 165	sort(fsinfo->layouttype, fsinfo->nlayouttypes,
 166		sizeof(*fsinfo->layouttype), ld_cmp, NULL);
 167
 168	for (i = 0; i < fsinfo->nlayouttypes; i++) {
 169		id = fsinfo->layouttype[i];
 170		ld_type = find_pnfs_driver(id);
 171		if (!ld_type) {
 172			request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX,
 173					id);
 174			ld_type = find_pnfs_driver(id);
 175		}
 176		if (ld_type)
 177			break;
 178	}
 179
 180	if (!ld_type) {
 181		dprintk("%s: No pNFS module found!\n", __func__);
 182		goto out_no_driver;
 183	}
 184
 185	server->pnfs_curr_ld = ld_type;
 186	if (ld_type->set_layoutdriver
 187	    && ld_type->set_layoutdriver(server, mntfh)) {
 188		printk(KERN_ERR "NFS: %s: Error initializing pNFS layout "
 189			"driver %u.\n", __func__, id);
 190		module_put(ld_type->owner);
 191		goto out_no_driver;
 192	}
 193	/* Bump the MDS count */
 194	atomic_inc(&server->nfs_client->cl_mds_count);
 195
 196	dprintk("%s: pNFS module for %u set\n", __func__, id);
 197	return;
 198
 199out_no_driver:
 200	dprintk("%s: Using NFSv4 I/O\n", __func__);
 201	server->pnfs_curr_ld = NULL;
 202}
 203
 204int
 205pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 206{
 207	int status = -EINVAL;
 208	struct pnfs_layoutdriver_type *tmp;
 209
 210	if (ld_type->id == 0) {
 211		printk(KERN_ERR "NFS: %s id 0 is reserved\n", __func__);
 212		return status;
 213	}
 214	if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
 215		printk(KERN_ERR "NFS: %s Layout driver must provide "
 216		       "alloc_lseg and free_lseg.\n", __func__);
 217		return status;
 218	}
 219
 220	spin_lock(&pnfs_spinlock);
 221	tmp = find_pnfs_driver_locked(ld_type->id);
 222	if (!tmp) {
 223		list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
 224		status = 0;
 225		dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
 226			ld_type->name);
 227	} else {
 228		printk(KERN_ERR "NFS: %s Module with id %d already loaded!\n",
 229			__func__, ld_type->id);
 230	}
 231	spin_unlock(&pnfs_spinlock);
 232
 233	return status;
 234}
 235EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);
 236
 237void
 238pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 239{
 240	dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
 241	spin_lock(&pnfs_spinlock);
 242	list_del(&ld_type->pnfs_tblid);
 243	spin_unlock(&pnfs_spinlock);
 244}
 245EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
 246
 247/*
 248 * pNFS client layout cache
 249 */
 250
 251/* Need to hold i_lock if caller does not already hold reference */
 252void
 253pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo)
 254{
 255	refcount_inc(&lo->plh_refcount);
 256}
 257
 258static struct pnfs_layout_hdr *
 259pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags)
 260{
 261	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
 262	return ld->alloc_layout_hdr(ino, gfp_flags);
 263}
 264
 265static void
 266pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
 267{
 268	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
 269	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
 270
 271	if (test_and_clear_bit(NFS_LAYOUT_HASHED, &lo->plh_flags)) {
 272		struct nfs_client *clp = server->nfs_client;
 273
 274		spin_lock(&clp->cl_lock);
 275		list_del_rcu(&lo->plh_layouts);
 276		spin_unlock(&clp->cl_lock);
 277	}
 278	put_cred(lo->plh_lc_cred);
 279	return ld->free_layout_hdr(lo);
 280}
 281
 282static void
 283pnfs_detach_layout_hdr(struct pnfs_layout_hdr *lo)
 284{
 285	struct nfs_inode *nfsi = NFS_I(lo->plh_inode);
 286	dprintk("%s: freeing layout cache %p\n", __func__, lo);
 287	nfsi->layout = NULL;
 288	/* Reset MDS Threshold I/O counters */
 289	nfsi->write_io = 0;
 290	nfsi->read_io = 0;
 291}
 292
 293void
 294pnfs_put_layout_hdr(struct pnfs_layout_hdr *lo)
 295{
 296	struct inode *inode;
 297	unsigned long i_state;
 298
 299	if (!lo)
 300		return;
 301	inode = lo->plh_inode;
 302	pnfs_layoutreturn_before_put_layout_hdr(lo);
 303
 304	if (refcount_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
 305		if (!list_empty(&lo->plh_segs))
 306			WARN_ONCE(1, "NFS: BUG unfreed layout segments.\n");
 307		pnfs_detach_layout_hdr(lo);
 308		i_state = inode->i_state;
 309		spin_unlock(&inode->i_lock);
 310		pnfs_free_layout_hdr(lo);
 311		/* Notify pnfs_destroy_layout_final() that we're done */
 312		if (i_state & (I_FREEING | I_CLEAR))
 313			wake_up_var(lo);
 314	}
 315}
 316
 317static struct inode *
 318pnfs_grab_inode_layout_hdr(struct pnfs_layout_hdr *lo)
 319{
 320	struct inode *inode = igrab(lo->plh_inode);
 321	if (inode)
 322		return inode;
 323	set_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags);
 324	return NULL;
 325}
 326
 327/*
 328 * Compare 2 layout stateid sequence ids, to see which is newer,
 329 * taking into account wraparound issues.
 330 */
 331static bool pnfs_seqid_is_newer(u32 s1, u32 s2)
 332{
 333	return (s32)(s1 - s2) > 0;
 334}
 335
 336static void pnfs_barrier_update(struct pnfs_layout_hdr *lo, u32 newseq)
 337{
 338	if (pnfs_seqid_is_newer(newseq, lo->plh_barrier) || !lo->plh_barrier)
 339		lo->plh_barrier = newseq;
 340}
 341
 342static void
 343pnfs_set_plh_return_info(struct pnfs_layout_hdr *lo, enum pnfs_iomode iomode,
 344			 u32 seq)
 345{
 346	if (lo->plh_return_iomode != 0 && lo->plh_return_iomode != iomode)
 347		iomode = IOMODE_ANY;
 348	lo->plh_return_iomode = iomode;
 349	set_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 350	/*
 351	 * We must set lo->plh_return_seq to avoid livelocks with
 352	 * pnfs_layout_need_return()
 353	 */
 354	if (seq == 0)
 355		seq = be32_to_cpu(lo->plh_stateid.seqid);
 356	if (!lo->plh_return_seq || pnfs_seqid_is_newer(seq, lo->plh_return_seq))
 357		lo->plh_return_seq = seq;
 358	pnfs_barrier_update(lo, seq);
 359}
 360
 361static void
 362pnfs_clear_layoutreturn_info(struct pnfs_layout_hdr *lo)
 363{
 364	struct pnfs_layout_segment *lseg;
 365	lo->plh_return_iomode = 0;
 366	lo->plh_return_seq = 0;
 367	clear_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 368	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
 369		if (!test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
 370			continue;
 371		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
 372	}
 373}
 374
 375static void pnfs_clear_layoutreturn_waitbit(struct pnfs_layout_hdr *lo)
 376{
 377	clear_bit_unlock(NFS_LAYOUT_RETURN, &lo->plh_flags);
 378	clear_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags);
 379	smp_mb__after_atomic();
 380	wake_up_bit(&lo->plh_flags, NFS_LAYOUT_RETURN);
 381	rpc_wake_up(&NFS_SERVER(lo->plh_inode)->roc_rpcwaitq);
 382}
 383
 384static void
 385pnfs_clear_lseg_state(struct pnfs_layout_segment *lseg,
 386		struct list_head *free_me)
 387{
 388	clear_bit(NFS_LSEG_ROC, &lseg->pls_flags);
 389	clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
 390	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags))
 391		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 392	if (test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
 393		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 394}
 395
 396/*
 397 * Update the seqid of a layout stateid after receiving
 398 * NFS4ERR_OLD_STATEID
 399 */
 400bool nfs4_layout_refresh_old_stateid(nfs4_stateid *dst,
 401		struct pnfs_layout_range *dst_range,
 402		struct inode *inode)
 403{
 404	struct pnfs_layout_hdr *lo;
 405	struct pnfs_layout_range range = {
 406		.iomode = IOMODE_ANY,
 407		.offset = 0,
 408		.length = NFS4_MAX_UINT64,
 409	};
 410	bool ret = false;
 411	LIST_HEAD(head);
 412	int err;
 413
 414	spin_lock(&inode->i_lock);
 415	lo = NFS_I(inode)->layout;
 416	if (lo &&  pnfs_layout_is_valid(lo) &&
 417	    nfs4_stateid_match_other(dst, &lo->plh_stateid)) {
 418		/* Is our call using the most recent seqid? If so, bump it */
 419		if (!nfs4_stateid_is_newer(&lo->plh_stateid, dst)) {
 420			nfs4_stateid_seqid_inc(dst);
 421			ret = true;
 422			goto out;
 423		}
 424		/* Try to update the seqid to the most recent */
 425		err = pnfs_mark_matching_lsegs_return(lo, &head, &range, 0);
 426		if (err != -EBUSY) {
 427			dst->seqid = lo->plh_stateid.seqid;
 428			*dst_range = range;
 429			ret = true;
 430		}
 431	}
 432out:
 433	spin_unlock(&inode->i_lock);
 434	pnfs_free_lseg_list(&head);
 435	return ret;
 436}
 437
 438/*
 439 * Mark a pnfs_layout_hdr and all associated layout segments as invalid
 440 *
 441 * In order to continue using the pnfs_layout_hdr, a full recovery
 442 * is required.
 443 * Note that caller must hold inode->i_lock.
 444 */
 445int
 446pnfs_mark_layout_stateid_invalid(struct pnfs_layout_hdr *lo,
 447		struct list_head *lseg_list)
 448{
 449	struct pnfs_layout_range range = {
 450		.iomode = IOMODE_ANY,
 451		.offset = 0,
 452		.length = NFS4_MAX_UINT64,
 453	};
 454	struct pnfs_layout_segment *lseg, *next;
 455
 456	set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 457	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 458		pnfs_clear_lseg_state(lseg, lseg_list);
 459	pnfs_clear_layoutreturn_info(lo);
 460	pnfs_free_returned_lsegs(lo, lseg_list, &range, 0);
 461	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags) &&
 462	    !test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
 463		pnfs_clear_layoutreturn_waitbit(lo);
 464	return !list_empty(&lo->plh_segs);
 465}
 466
 467static int
 468pnfs_iomode_to_fail_bit(u32 iomode)
 469{
 470	return iomode == IOMODE_RW ?
 471		NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 472}
 473
 474static void
 475pnfs_layout_set_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 476{
 477	lo->plh_retry_timestamp = jiffies;
 478	if (!test_and_set_bit(fail_bit, &lo->plh_flags))
 479		refcount_inc(&lo->plh_refcount);
 480}
 481
 482static void
 483pnfs_layout_clear_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 484{
 485	if (test_and_clear_bit(fail_bit, &lo->plh_flags))
 486		refcount_dec(&lo->plh_refcount);
 487}
 488
 489static void
 490pnfs_layout_io_set_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 491{
 492	struct inode *inode = lo->plh_inode;
 493	struct pnfs_layout_range range = {
 494		.iomode = iomode,
 495		.offset = 0,
 496		.length = NFS4_MAX_UINT64,
 497	};
 498	LIST_HEAD(head);
 499
 500	spin_lock(&inode->i_lock);
 501	pnfs_layout_set_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
 502	pnfs_mark_matching_lsegs_invalid(lo, &head, &range, 0);
 503	spin_unlock(&inode->i_lock);
 504	pnfs_free_lseg_list(&head);
 505	dprintk("%s Setting layout IOMODE_%s fail bit\n", __func__,
 506			iomode == IOMODE_RW ?  "RW" : "READ");
 507}
 508
 509static bool
 510pnfs_layout_io_test_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 511{
 512	unsigned long start, end;
 513	int fail_bit = pnfs_iomode_to_fail_bit(iomode);
 514
 515	if (test_bit(fail_bit, &lo->plh_flags) == 0)
 516		return false;
 517	end = jiffies;
 518	start = end - PNFS_LAYOUTGET_RETRY_TIMEOUT;
 519	if (!time_in_range(lo->plh_retry_timestamp, start, end)) {
 520		/* It is time to retry the failed layoutgets */
 521		pnfs_layout_clear_fail_bit(lo, fail_bit);
 522		return false;
 523	}
 524	return true;
 525}
 526
 527static void
 528pnfs_init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg,
 529		const struct pnfs_layout_range *range,
 530		const nfs4_stateid *stateid)
 531{
 532	INIT_LIST_HEAD(&lseg->pls_list);
 533	INIT_LIST_HEAD(&lseg->pls_lc_list);
 534	INIT_LIST_HEAD(&lseg->pls_commits);
 535	refcount_set(&lseg->pls_refcount, 1);
 536	set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
 537	lseg->pls_layout = lo;
 538	lseg->pls_range = *range;
 539	lseg->pls_seq = be32_to_cpu(stateid->seqid);
 540}
 541
 542static void pnfs_free_lseg(struct pnfs_layout_segment *lseg)
 543{
 544	if (lseg != NULL) {
 545		struct inode *inode = lseg->pls_layout->plh_inode;
 546		NFS_SERVER(inode)->pnfs_curr_ld->free_lseg(lseg);
 547	}
 548}
 549
 550static void
 551pnfs_layout_remove_lseg(struct pnfs_layout_hdr *lo,
 552		struct pnfs_layout_segment *lseg)
 553{
 554	WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 555	list_del_init(&lseg->pls_list);
 556	/* Matched by pnfs_get_layout_hdr in pnfs_layout_insert_lseg */
 557	refcount_dec(&lo->plh_refcount);
 558	if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
 559		return;
 560	if (list_empty(&lo->plh_segs) &&
 561	    !test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) &&
 562	    !test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
 563		if (atomic_read(&lo->plh_outstanding) == 0)
 564			set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 565		clear_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 566	}
 567}
 568
 569static bool
 570pnfs_cache_lseg_for_layoutreturn(struct pnfs_layout_hdr *lo,
 571		struct pnfs_layout_segment *lseg)
 572{
 573	if (test_and_clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags) &&
 574	    pnfs_layout_is_valid(lo)) {
 575		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
 576		list_move_tail(&lseg->pls_list, &lo->plh_return_segs);
 577		return true;
 578	}
 579	return false;
 580}
 581
 582void
 583pnfs_put_lseg(struct pnfs_layout_segment *lseg)
 584{
 585	struct pnfs_layout_hdr *lo;
 586	struct inode *inode;
 587
 588	if (!lseg)
 589		return;
 590
 591	dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
 592		refcount_read(&lseg->pls_refcount),
 593		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 594
 595	lo = lseg->pls_layout;
 596	inode = lo->plh_inode;
 597
 598	if (refcount_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
 599		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 600			spin_unlock(&inode->i_lock);
 601			return;
 602		}
 603		pnfs_get_layout_hdr(lo);
 604		pnfs_layout_remove_lseg(lo, lseg);
 605		if (pnfs_cache_lseg_for_layoutreturn(lo, lseg))
 606			lseg = NULL;
 607		spin_unlock(&inode->i_lock);
 608		pnfs_free_lseg(lseg);
 609		pnfs_put_layout_hdr(lo);
 610	}
 611}
 612EXPORT_SYMBOL_GPL(pnfs_put_lseg);
 613
 614/*
 615 * is l2 fully contained in l1?
 616 *   start1                             end1
 617 *   [----------------------------------)
 618 *           start2           end2
 619 *           [----------------)
 620 */
 621static bool
 622pnfs_lseg_range_contained(const struct pnfs_layout_range *l1,
 623		 const struct pnfs_layout_range *l2)
 624{
 625	u64 start1 = l1->offset;
 626	u64 end1 = pnfs_end_offset(start1, l1->length);
 627	u64 start2 = l2->offset;
 628	u64 end2 = pnfs_end_offset(start2, l2->length);
 629
 630	return (start1 <= start2) && (end1 >= end2);
 631}
 632
 633static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
 634		struct list_head *tmp_list)
 635{
 636	if (!refcount_dec_and_test(&lseg->pls_refcount))
 637		return false;
 638	pnfs_layout_remove_lseg(lseg->pls_layout, lseg);
 639	list_add(&lseg->pls_list, tmp_list);
 640	return true;
 641}
 642
 643/* Returns 1 if lseg is removed from list, 0 otherwise */
 644static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
 645			     struct list_head *tmp_list)
 646{
 647	int rv = 0;
 648
 649	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 650		/* Remove the reference keeping the lseg in the
 651		 * list.  It will now be removed when all
 652		 * outstanding io is finished.
 653		 */
 654		dprintk("%s: lseg %p ref %d\n", __func__, lseg,
 655			refcount_read(&lseg->pls_refcount));
 656		if (pnfs_lseg_dec_and_remove_zero(lseg, tmp_list))
 657			rv = 1;
 658	}
 659	return rv;
 660}
 661
 
 
 
 
 
 
 
 
 
 662static bool
 663pnfs_should_free_range(const struct pnfs_layout_range *lseg_range,
 664		 const struct pnfs_layout_range *recall_range)
 665{
 666	return (recall_range->iomode == IOMODE_ANY ||
 667		lseg_range->iomode == recall_range->iomode) &&
 668	       pnfs_lseg_range_intersecting(lseg_range, recall_range);
 669}
 670
 671static bool
 672pnfs_match_lseg_recall(const struct pnfs_layout_segment *lseg,
 673		const struct pnfs_layout_range *recall_range,
 674		u32 seq)
 675{
 676	if (seq != 0 && pnfs_seqid_is_newer(lseg->pls_seq, seq))
 677		return false;
 678	if (recall_range == NULL)
 679		return true;
 680	return pnfs_should_free_range(&lseg->pls_range, recall_range);
 681}
 682
 683/**
 684 * pnfs_mark_matching_lsegs_invalid - tear down lsegs or mark them for later
 685 * @lo: layout header containing the lsegs
 686 * @tmp_list: list head where doomed lsegs should go
 687 * @recall_range: optional recall range argument to match (may be NULL)
 688 * @seq: only invalidate lsegs obtained prior to this sequence (may be 0)
 689 *
 690 * Walk the list of lsegs in the layout header, and tear down any that should
 691 * be destroyed. If "recall_range" is specified then the segment must match
 692 * that range. If "seq" is non-zero, then only match segments that were handed
 693 * out at or before that sequence.
 694 *
 695 * Returns number of matching invalid lsegs remaining in list after scanning
 696 * it and purging them.
 697 */
 698int
 699pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 700			    struct list_head *tmp_list,
 701			    const struct pnfs_layout_range *recall_range,
 702			    u32 seq)
 703{
 704	struct pnfs_layout_segment *lseg, *next;
 705	int remaining = 0;
 706
 707	dprintk("%s:Begin lo %p\n", __func__, lo);
 708
 709	if (list_empty(&lo->plh_segs))
 710		return 0;
 711	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 712		if (pnfs_match_lseg_recall(lseg, recall_range, seq)) {
 713			dprintk("%s: freeing lseg %p iomode %d seq %u "
 714				"offset %llu length %llu\n", __func__,
 715				lseg, lseg->pls_range.iomode, lseg->pls_seq,
 716				lseg->pls_range.offset, lseg->pls_range.length);
 717			if (!mark_lseg_invalid(lseg, tmp_list))
 718				remaining++;
 719		}
 720	dprintk("%s:Return %i\n", __func__, remaining);
 721	return remaining;
 722}
 723
 724static void
 725pnfs_free_returned_lsegs(struct pnfs_layout_hdr *lo,
 726		struct list_head *free_me,
 727		const struct pnfs_layout_range *range,
 728		u32 seq)
 729{
 730	struct pnfs_layout_segment *lseg, *next;
 731
 732	list_for_each_entry_safe(lseg, next, &lo->plh_return_segs, pls_list) {
 733		if (pnfs_match_lseg_recall(lseg, range, seq))
 734			list_move_tail(&lseg->pls_list, free_me);
 735	}
 736}
 737
 738/* note free_me must contain lsegs from a single layout_hdr */
 739void
 740pnfs_free_lseg_list(struct list_head *free_me)
 741{
 742	struct pnfs_layout_segment *lseg, *tmp;
 743
 744	if (list_empty(free_me))
 745		return;
 746
 747	list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
 748		list_del(&lseg->pls_list);
 749		pnfs_free_lseg(lseg);
 750	}
 751}
 752
 753static struct pnfs_layout_hdr *__pnfs_destroy_layout(struct nfs_inode *nfsi)
 
 754{
 755	struct pnfs_layout_hdr *lo;
 756	LIST_HEAD(tmp_list);
 757
 758	spin_lock(&nfsi->vfs_inode.i_lock);
 759	lo = nfsi->layout;
 760	if (lo) {
 761		pnfs_get_layout_hdr(lo);
 762		pnfs_mark_layout_stateid_invalid(lo, &tmp_list);
 763		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RO_FAILED);
 764		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RW_FAILED);
 765		spin_unlock(&nfsi->vfs_inode.i_lock);
 766		pnfs_free_lseg_list(&tmp_list);
 767		nfs_commit_inode(&nfsi->vfs_inode, 0);
 768		pnfs_put_layout_hdr(lo);
 769	} else
 770		spin_unlock(&nfsi->vfs_inode.i_lock);
 771	return lo;
 772}
 773
 774void pnfs_destroy_layout(struct nfs_inode *nfsi)
 775{
 776	__pnfs_destroy_layout(nfsi);
 777}
 778EXPORT_SYMBOL_GPL(pnfs_destroy_layout);
 779
 780static bool pnfs_layout_removed(struct nfs_inode *nfsi,
 781				struct pnfs_layout_hdr *lo)
 782{
 783	bool ret;
 784
 785	spin_lock(&nfsi->vfs_inode.i_lock);
 786	ret = nfsi->layout != lo;
 787	spin_unlock(&nfsi->vfs_inode.i_lock);
 788	return ret;
 789}
 790
 791void pnfs_destroy_layout_final(struct nfs_inode *nfsi)
 792{
 793	struct pnfs_layout_hdr *lo = __pnfs_destroy_layout(nfsi);
 794
 795	if (lo)
 796		wait_var_event(lo, pnfs_layout_removed(nfsi, lo));
 797}
 798
 799static bool
 800pnfs_layout_add_bulk_destroy_list(struct inode *inode,
 801		struct list_head *layout_list)
 802{
 803	struct pnfs_layout_hdr *lo;
 804	bool ret = false;
 805
 806	spin_lock(&inode->i_lock);
 807	lo = NFS_I(inode)->layout;
 808	if (lo != NULL && list_empty(&lo->plh_bulk_destroy)) {
 809		pnfs_get_layout_hdr(lo);
 810		list_add(&lo->plh_bulk_destroy, layout_list);
 811		ret = true;
 812	}
 813	spin_unlock(&inode->i_lock);
 814	return ret;
 815}
 816
 817/* Caller must hold rcu_read_lock and clp->cl_lock */
 818static int
 819pnfs_layout_bulk_destroy_byserver_locked(struct nfs_client *clp,
 820		struct nfs_server *server,
 821		struct list_head *layout_list)
 822	__must_hold(&clp->cl_lock)
 823	__must_hold(RCU)
 824{
 825	struct pnfs_layout_hdr *lo, *next;
 826	struct inode *inode;
 827
 828	list_for_each_entry_safe(lo, next, &server->layouts, plh_layouts) {
 829		if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags) ||
 830		    test_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags) ||
 831		    !list_empty(&lo->plh_bulk_destroy))
 832			continue;
 833		/* If the sb is being destroyed, just bail */
 834		if (!nfs_sb_active(server->super))
 835			break;
 836		inode = pnfs_grab_inode_layout_hdr(lo);
 837		if (inode != NULL) {
 838			if (test_and_clear_bit(NFS_LAYOUT_HASHED, &lo->plh_flags))
 839				list_del_rcu(&lo->plh_layouts);
 840			if (pnfs_layout_add_bulk_destroy_list(inode,
 841						layout_list))
 842				continue;
 843			rcu_read_unlock();
 844			spin_unlock(&clp->cl_lock);
 845			iput(inode);
 846		} else {
 847			rcu_read_unlock();
 848			spin_unlock(&clp->cl_lock);
 
 849		}
 850		nfs_sb_deactive(server->super);
 851		spin_lock(&clp->cl_lock);
 852		rcu_read_lock();
 853		return -EAGAIN;
 854	}
 855	return 0;
 856}
 857
 858static int
 859pnfs_layout_free_bulk_destroy_list(struct list_head *layout_list,
 860		bool is_bulk_recall)
 861{
 862	struct pnfs_layout_hdr *lo;
 863	struct inode *inode;
 864	LIST_HEAD(lseg_list);
 865	int ret = 0;
 866
 867	while (!list_empty(layout_list)) {
 868		lo = list_entry(layout_list->next, struct pnfs_layout_hdr,
 869				plh_bulk_destroy);
 870		dprintk("%s freeing layout for inode %lu\n", __func__,
 871			lo->plh_inode->i_ino);
 872		inode = lo->plh_inode;
 873
 874		pnfs_layoutcommit_inode(inode, false);
 875
 876		spin_lock(&inode->i_lock);
 877		list_del_init(&lo->plh_bulk_destroy);
 878		if (pnfs_mark_layout_stateid_invalid(lo, &lseg_list)) {
 879			if (is_bulk_recall)
 880				set_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 881			ret = -EAGAIN;
 882		}
 883		spin_unlock(&inode->i_lock);
 884		pnfs_free_lseg_list(&lseg_list);
 885		/* Free all lsegs that are attached to commit buckets */
 886		nfs_commit_inode(inode, 0);
 887		pnfs_put_layout_hdr(lo);
 888		nfs_iput_and_deactive(inode);
 889	}
 890	return ret;
 891}
 892
 893int
 894pnfs_destroy_layouts_byfsid(struct nfs_client *clp,
 895		struct nfs_fsid *fsid,
 896		bool is_recall)
 897{
 898	struct nfs_server *server;
 899	LIST_HEAD(layout_list);
 900
 901	spin_lock(&clp->cl_lock);
 902	rcu_read_lock();
 903restart:
 904	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 905		if (memcmp(&server->fsid, fsid, sizeof(*fsid)) != 0)
 906			continue;
 907		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 908				server,
 909				&layout_list) != 0)
 910			goto restart;
 911	}
 912	rcu_read_unlock();
 913	spin_unlock(&clp->cl_lock);
 914
 915	if (list_empty(&layout_list))
 916		return 0;
 917	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 918}
 919
 920int
 921pnfs_destroy_layouts_byclid(struct nfs_client *clp,
 922		bool is_recall)
 923{
 924	struct nfs_server *server;
 925	LIST_HEAD(layout_list);
 926
 927	spin_lock(&clp->cl_lock);
 928	rcu_read_lock();
 929restart:
 930	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 931		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 932					server,
 933					&layout_list) != 0)
 934			goto restart;
 935	}
 936	rcu_read_unlock();
 937	spin_unlock(&clp->cl_lock);
 938
 939	if (list_empty(&layout_list))
 940		return 0;
 941	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 942}
 943
 944/*
 945 * Called by the state manager to remove all layouts established under an
 946 * expired lease.
 947 */
 948void
 949pnfs_destroy_all_layouts(struct nfs_client *clp)
 950{
 951	nfs4_deviceid_mark_client_invalid(clp);
 952	nfs4_deviceid_purge_client(clp);
 953
 954	pnfs_destroy_layouts_byclid(clp, false);
 955}
 956
 957static void
 958pnfs_set_layout_cred(struct pnfs_layout_hdr *lo, const struct cred *cred)
 959{
 960	const struct cred *old;
 961
 962	if (cred && cred_fscmp(lo->plh_lc_cred, cred) != 0) {
 963		old = xchg(&lo->plh_lc_cred, get_cred(cred));
 964		put_cred(old);
 965	}
 966}
 967
 968/* update lo->plh_stateid with new if is more recent */
 969void
 970pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
 971			const struct cred *cred, bool update_barrier)
 972{
 973	u32 oldseq = be32_to_cpu(lo->plh_stateid.seqid);
 974	u32 newseq = be32_to_cpu(new->seqid);
 
 
 975
 976	if (!pnfs_layout_is_valid(lo)) {
 977		pnfs_set_layout_cred(lo, cred);
 978		nfs4_stateid_copy(&lo->plh_stateid, new);
 979		lo->plh_barrier = newseq;
 980		pnfs_clear_layoutreturn_info(lo);
 981		clear_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 982		return;
 983	}
 984
 985	if (pnfs_seqid_is_newer(newseq, oldseq))
 986		nfs4_stateid_copy(&lo->plh_stateid, new);
 987
 988	if (update_barrier) {
 989		pnfs_barrier_update(lo, newseq);
 990		return;
 
 991	}
 992	/*
 993	 * Because of wraparound, we want to keep the barrier
 994	 * "close" to the current seqids. We really only want to
 995	 * get here from a layoutget call.
 996	 */
 997	if (atomic_read(&lo->plh_outstanding) == 1)
 998		 pnfs_barrier_update(lo, be32_to_cpu(lo->plh_stateid.seqid));
 999}
1000
1001static bool
1002pnfs_layout_stateid_blocked(const struct pnfs_layout_hdr *lo,
1003		const nfs4_stateid *stateid)
1004{
1005	u32 seqid = be32_to_cpu(stateid->seqid);
1006
1007	return lo->plh_barrier && pnfs_seqid_is_newer(lo->plh_barrier, seqid);
1008}
1009
1010/* lget is set to 1 if called from inside send_layoutget call chain */
1011static bool
1012pnfs_layoutgets_blocked(const struct pnfs_layout_hdr *lo)
1013{
1014	return lo->plh_block_lgets ||
1015		test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
1016}
1017
1018static struct nfs_server *
1019pnfs_find_server(struct inode *inode, struct nfs_open_context *ctx)
1020{
1021	struct nfs_server *server;
1022
1023	if (inode) {
1024		server = NFS_SERVER(inode);
1025	} else {
1026		struct dentry *parent_dir = dget_parent(ctx->dentry);
1027		server = NFS_SERVER(parent_dir->d_inode);
1028		dput(parent_dir);
1029	}
1030	return server;
1031}
1032
1033static void nfs4_free_pages(struct page **pages, size_t size)
1034{
1035	int i;
1036
1037	if (!pages)
1038		return;
1039
1040	for (i = 0; i < size; i++) {
1041		if (!pages[i])
1042			break;
1043		__free_page(pages[i]);
1044	}
1045	kfree(pages);
1046}
1047
1048static struct page **nfs4_alloc_pages(size_t size, gfp_t gfp_flags)
1049{
1050	struct page **pages;
1051	int i;
1052
1053	pages = kmalloc_array(size, sizeof(struct page *), gfp_flags);
1054	if (!pages) {
1055		dprintk("%s: can't alloc array of %zu pages\n", __func__, size);
1056		return NULL;
1057	}
1058
1059	for (i = 0; i < size; i++) {
1060		pages[i] = alloc_page(gfp_flags);
1061		if (!pages[i]) {
1062			dprintk("%s: failed to allocate page\n", __func__);
1063			nfs4_free_pages(pages, i);
1064			return NULL;
1065		}
1066	}
1067
1068	return pages;
1069}
1070
1071static struct nfs4_layoutget *
1072pnfs_alloc_init_layoutget_args(struct inode *ino,
1073	   struct nfs_open_context *ctx,
1074	   const nfs4_stateid *stateid,
1075	   const struct pnfs_layout_range *range,
1076	   gfp_t gfp_flags)
1077{
1078	struct nfs_server *server = pnfs_find_server(ino, ctx);
1079	size_t max_reply_sz = server->pnfs_curr_ld->max_layoutget_response;
1080	size_t max_pages = max_response_pages(server);
1081	struct nfs4_layoutget *lgp;
1082
1083	dprintk("--> %s\n", __func__);
1084
1085	lgp = kzalloc(sizeof(*lgp), gfp_flags);
1086	if (lgp == NULL)
1087		return NULL;
1088
1089	if (max_reply_sz) {
1090		size_t npages = (max_reply_sz + PAGE_SIZE - 1) >> PAGE_SHIFT;
1091		if (npages < max_pages)
1092			max_pages = npages;
1093	}
1094
1095	lgp->args.layout.pages = nfs4_alloc_pages(max_pages, gfp_flags);
1096	if (!lgp->args.layout.pages) {
1097		kfree(lgp);
1098		return NULL;
1099	}
1100	lgp->args.layout.pglen = max_pages * PAGE_SIZE;
1101	lgp->res.layoutp = &lgp->args.layout;
1102
1103	/* Don't confuse uninitialised result and success */
1104	lgp->res.status = -NFS4ERR_DELAY;
1105
1106	lgp->args.minlength = PAGE_SIZE;
1107	if (lgp->args.minlength > range->length)
1108		lgp->args.minlength = range->length;
1109	if (ino) {
1110		loff_t i_size = i_size_read(ino);
1111
1112		if (range->iomode == IOMODE_READ) {
1113			if (range->offset >= i_size)
1114				lgp->args.minlength = 0;
1115			else if (i_size - range->offset < lgp->args.minlength)
1116				lgp->args.minlength = i_size - range->offset;
1117		}
1118	}
1119	lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
1120	pnfs_copy_range(&lgp->args.range, range);
1121	lgp->args.type = server->pnfs_curr_ld->id;
1122	lgp->args.inode = ino;
1123	lgp->args.ctx = get_nfs_open_context(ctx);
1124	nfs4_stateid_copy(&lgp->args.stateid, stateid);
1125	lgp->gfp_flags = gfp_flags;
1126	lgp->cred = ctx->cred;
1127	return lgp;
1128}
1129
1130void pnfs_layoutget_free(struct nfs4_layoutget *lgp)
1131{
1132	size_t max_pages = lgp->args.layout.pglen / PAGE_SIZE;
1133
1134	nfs4_free_pages(lgp->args.layout.pages, max_pages);
1135	pnfs_put_layout_hdr(lgp->lo);
 
 
1136	put_nfs_open_context(lgp->args.ctx);
1137	kfree(lgp);
1138}
1139
1140static void pnfs_clear_layoutcommit(struct inode *inode,
1141		struct list_head *head)
1142{
1143	struct nfs_inode *nfsi = NFS_I(inode);
1144	struct pnfs_layout_segment *lseg, *tmp;
1145
1146	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
1147		return;
1148	list_for_each_entry_safe(lseg, tmp, &nfsi->layout->plh_segs, pls_list) {
1149		if (!test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
1150			continue;
1151		pnfs_lseg_dec_and_remove_zero(lseg, head);
1152	}
1153}
1154
1155void pnfs_layoutreturn_free_lsegs(struct pnfs_layout_hdr *lo,
1156		const nfs4_stateid *arg_stateid,
1157		const struct pnfs_layout_range *range,
1158		const nfs4_stateid *stateid)
1159{
1160	struct inode *inode = lo->plh_inode;
1161	LIST_HEAD(freeme);
1162
1163	spin_lock(&inode->i_lock);
1164	if (!pnfs_layout_is_valid(lo) ||
1165	    !nfs4_stateid_match_other(&lo->plh_stateid, arg_stateid))
1166		goto out_unlock;
1167	if (stateid) {
1168		u32 seq = be32_to_cpu(arg_stateid->seqid);
1169
1170		pnfs_mark_matching_lsegs_invalid(lo, &freeme, range, seq);
1171		pnfs_free_returned_lsegs(lo, &freeme, range, seq);
1172		pnfs_set_layout_stateid(lo, stateid, NULL, true);
1173	} else
1174		pnfs_mark_layout_stateid_invalid(lo, &freeme);
1175out_unlock:
1176	pnfs_clear_layoutreturn_waitbit(lo);
1177	spin_unlock(&inode->i_lock);
1178	pnfs_free_lseg_list(&freeme);
1179
1180}
1181
1182static bool
1183pnfs_prepare_layoutreturn(struct pnfs_layout_hdr *lo,
1184		nfs4_stateid *stateid,
1185		const struct cred **cred,
1186		enum pnfs_iomode *iomode)
1187{
1188	/* Serialise LAYOUTGET/LAYOUTRETURN */
1189	if (atomic_read(&lo->plh_outstanding) != 0)
1190		return false;
1191	if (test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
1192		return false;
1193	set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
1194	pnfs_get_layout_hdr(lo);
1195	nfs4_stateid_copy(stateid, &lo->plh_stateid);
1196	*cred = get_cred(lo->plh_lc_cred);
1197	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags)) {
1198		if (lo->plh_return_seq != 0)
1199			stateid->seqid = cpu_to_be32(lo->plh_return_seq);
 
 
 
1200		if (iomode != NULL)
1201			*iomode = lo->plh_return_iomode;
1202		pnfs_clear_layoutreturn_info(lo);
1203	} else if (iomode != NULL)
 
 
 
 
1204		*iomode = IOMODE_ANY;
1205	pnfs_barrier_update(lo, be32_to_cpu(stateid->seqid));
1206	return true;
1207}
1208
1209static void
1210pnfs_init_layoutreturn_args(struct nfs4_layoutreturn_args *args,
1211		struct pnfs_layout_hdr *lo,
1212		const nfs4_stateid *stateid,
1213		enum pnfs_iomode iomode)
1214{
1215	struct inode *inode = lo->plh_inode;
1216
1217	args->layout_type = NFS_SERVER(inode)->pnfs_curr_ld->id;
1218	args->inode = inode;
1219	args->range.iomode = iomode;
1220	args->range.offset = 0;
1221	args->range.length = NFS4_MAX_UINT64;
1222	args->layout = lo;
1223	nfs4_stateid_copy(&args->stateid, stateid);
1224}
1225
1226static int
1227pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo,
1228		       const nfs4_stateid *stateid,
1229		       const struct cred **pcred,
1230		       enum pnfs_iomode iomode,
1231		       bool sync)
1232{
1233	struct inode *ino = lo->plh_inode;
1234	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1235	struct nfs4_layoutreturn *lrp;
1236	const struct cred *cred = *pcred;
1237	int status = 0;
1238
1239	*pcred = NULL;
1240	lrp = kzalloc(sizeof(*lrp), GFP_NOFS);
1241	if (unlikely(lrp == NULL)) {
1242		status = -ENOMEM;
1243		spin_lock(&ino->i_lock);
1244		pnfs_clear_layoutreturn_waitbit(lo);
1245		spin_unlock(&ino->i_lock);
1246		put_cred(cred);
1247		pnfs_put_layout_hdr(lo);
1248		goto out;
1249	}
1250
1251	pnfs_init_layoutreturn_args(&lrp->args, lo, stateid, iomode);
1252	lrp->args.ld_private = &lrp->ld_private;
1253	lrp->clp = NFS_SERVER(ino)->nfs_client;
1254	lrp->cred = cred;
1255	if (ld->prepare_layoutreturn)
1256		ld->prepare_layoutreturn(&lrp->args);
1257
1258	status = nfs4_proc_layoutreturn(lrp, sync);
1259out:
1260	dprintk("<-- %s status: %d\n", __func__, status);
1261	return status;
1262}
1263
1264static bool
1265pnfs_layout_segments_returnable(struct pnfs_layout_hdr *lo,
1266				enum pnfs_iomode iomode,
1267				u32 seq)
1268{
1269	struct pnfs_layout_range recall_range = {
1270		.length = NFS4_MAX_UINT64,
1271		.iomode = iomode,
1272	};
1273	return pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs,
1274					       &recall_range, seq) != -EBUSY;
1275}
1276
1277/* Return true if layoutreturn is needed */
1278static bool
1279pnfs_layout_need_return(struct pnfs_layout_hdr *lo)
1280{
 
 
 
 
1281	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1282		return false;
1283	return pnfs_layout_segments_returnable(lo, lo->plh_return_iomode,
1284					       lo->plh_return_seq);
 
 
 
 
 
 
 
 
 
 
 
 
 
1285}
1286
1287static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo)
1288{
1289	struct inode *inode= lo->plh_inode;
1290
1291	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1292		return;
1293	spin_lock(&inode->i_lock);
1294	if (pnfs_layout_need_return(lo)) {
1295		const struct cred *cred;
1296		nfs4_stateid stateid;
1297		enum pnfs_iomode iomode;
1298		bool send;
1299
1300		send = pnfs_prepare_layoutreturn(lo, &stateid, &cred, &iomode);
1301		spin_unlock(&inode->i_lock);
1302		if (send) {
1303			/* Send an async layoutreturn so we dont deadlock */
1304			pnfs_send_layoutreturn(lo, &stateid, &cred, iomode, false);
1305		}
1306	} else
1307		spin_unlock(&inode->i_lock);
1308}
1309
1310/*
1311 * Initiates a LAYOUTRETURN(FILE), and removes the pnfs_layout_hdr
1312 * when the layout segment list is empty.
1313 *
1314 * Note that a pnfs_layout_hdr can exist with an empty layout segment
1315 * list when LAYOUTGET has failed, or when LAYOUTGET succeeded, but the
1316 * deviceid is marked invalid.
1317 */
1318int
1319_pnfs_return_layout(struct inode *ino)
1320{
1321	struct pnfs_layout_hdr *lo = NULL;
1322	struct nfs_inode *nfsi = NFS_I(ino);
1323	struct pnfs_layout_range range = {
1324		.iomode		= IOMODE_ANY,
1325		.offset		= 0,
1326		.length		= NFS4_MAX_UINT64,
1327	};
1328	LIST_HEAD(tmp_list);
1329	const struct cred *cred;
1330	nfs4_stateid stateid;
1331	int status = 0;
1332	bool send, valid_layout;
1333
1334	dprintk("NFS: %s for inode %lu\n", __func__, ino->i_ino);
1335
1336	spin_lock(&ino->i_lock);
1337	lo = nfsi->layout;
1338	if (!lo) {
1339		spin_unlock(&ino->i_lock);
1340		dprintk("NFS: %s no layout to return\n", __func__);
1341		goto out;
1342	}
1343	/* Reference matched in nfs4_layoutreturn_release */
1344	pnfs_get_layout_hdr(lo);
1345	/* Is there an outstanding layoutreturn ? */
1346	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1347		spin_unlock(&ino->i_lock);
1348		if (wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1349					TASK_UNINTERRUPTIBLE))
1350			goto out_put_layout_hdr;
1351		spin_lock(&ino->i_lock);
1352	}
1353	valid_layout = pnfs_layout_is_valid(lo);
1354	pnfs_clear_layoutcommit(ino, &tmp_list);
1355	pnfs_mark_matching_lsegs_return(lo, &tmp_list, &range, 0);
1356
1357	if (NFS_SERVER(ino)->pnfs_curr_ld->return_range)
 
 
 
 
 
1358		NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo, &range);
 
1359
1360	/* Don't send a LAYOUTRETURN if list was initially empty */
1361	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) ||
1362			!valid_layout) {
1363		spin_unlock(&ino->i_lock);
1364		dprintk("NFS: %s no layout segments to return\n", __func__);
1365		goto out_wait_layoutreturn;
1366	}
1367
1368	send = pnfs_prepare_layoutreturn(lo, &stateid, &cred, NULL);
1369	spin_unlock(&ino->i_lock);
1370	if (send)
1371		status = pnfs_send_layoutreturn(lo, &stateid, &cred, IOMODE_ANY, true);
1372out_wait_layoutreturn:
1373	wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN, TASK_UNINTERRUPTIBLE);
1374out_put_layout_hdr:
1375	pnfs_free_lseg_list(&tmp_list);
1376	pnfs_put_layout_hdr(lo);
1377out:
1378	dprintk("<-- %s status: %d\n", __func__, status);
1379	return status;
1380}
1381
1382int
1383pnfs_commit_and_return_layout(struct inode *inode)
1384{
1385	struct pnfs_layout_hdr *lo;
1386	int ret;
1387
1388	spin_lock(&inode->i_lock);
1389	lo = NFS_I(inode)->layout;
1390	if (lo == NULL) {
1391		spin_unlock(&inode->i_lock);
1392		return 0;
1393	}
1394	pnfs_get_layout_hdr(lo);
1395	/* Block new layoutgets and read/write to ds */
1396	lo->plh_block_lgets++;
1397	spin_unlock(&inode->i_lock);
1398	filemap_fdatawait(inode->i_mapping);
1399	ret = pnfs_layoutcommit_inode(inode, true);
1400	if (ret == 0)
1401		ret = _pnfs_return_layout(inode);
1402	spin_lock(&inode->i_lock);
1403	lo->plh_block_lgets--;
1404	spin_unlock(&inode->i_lock);
1405	pnfs_put_layout_hdr(lo);
1406	return ret;
1407}
1408
1409bool pnfs_roc(struct inode *ino,
1410		struct nfs4_layoutreturn_args *args,
1411		struct nfs4_layoutreturn_res *res,
1412		const struct cred *cred)
1413{
1414	struct nfs_inode *nfsi = NFS_I(ino);
1415	struct nfs_open_context *ctx;
1416	struct nfs4_state *state;
1417	struct pnfs_layout_hdr *lo;
1418	struct pnfs_layout_segment *lseg, *next;
1419	const struct cred *lc_cred;
1420	nfs4_stateid stateid;
1421	enum pnfs_iomode iomode = 0;
1422	bool layoutreturn = false, roc = false;
1423	bool skip_read = false;
1424
1425	if (!nfs_have_layout(ino))
1426		return false;
1427retry:
1428	rcu_read_lock();
1429	spin_lock(&ino->i_lock);
1430	lo = nfsi->layout;
1431	if (!lo || !pnfs_layout_is_valid(lo) ||
1432	    test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1433		lo = NULL;
1434		goto out_noroc;
1435	}
1436	pnfs_get_layout_hdr(lo);
1437	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1438		spin_unlock(&ino->i_lock);
1439		rcu_read_unlock();
1440		wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1441				TASK_UNINTERRUPTIBLE);
1442		pnfs_put_layout_hdr(lo);
1443		goto retry;
1444	}
1445
1446	/* no roc if we hold a delegation */
1447	if (nfs4_check_delegation(ino, FMODE_READ)) {
1448		if (nfs4_check_delegation(ino, FMODE_WRITE))
1449			goto out_noroc;
1450		skip_read = true;
1451	}
1452
1453	list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
1454		state = ctx->state;
1455		if (state == NULL)
1456			continue;
1457		/* Don't return layout if there is open file state */
1458		if (state->state & FMODE_WRITE)
1459			goto out_noroc;
1460		if (state->state & FMODE_READ)
1461			skip_read = true;
1462	}
1463
1464
1465	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list) {
1466		if (skip_read && lseg->pls_range.iomode == IOMODE_READ)
1467			continue;
1468		/* If we are sending layoutreturn, invalidate all valid lsegs */
1469		if (!test_and_clear_bit(NFS_LSEG_ROC, &lseg->pls_flags))
1470			continue;
1471		/*
1472		 * Note: mark lseg for return so pnfs_layout_remove_lseg
1473		 * doesn't invalidate the layout for us.
1474		 */
1475		set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
1476		if (!mark_lseg_invalid(lseg, &lo->plh_return_segs))
1477			continue;
1478		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
1479	}
1480
1481	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1482		goto out_noroc;
1483
1484	/* ROC in two conditions:
1485	 * 1. there are ROC lsegs
1486	 * 2. we don't send layoutreturn
1487	 */
1488	/* lo ref dropped in pnfs_roc_release() */
1489	layoutreturn = pnfs_prepare_layoutreturn(lo, &stateid, &lc_cred, &iomode);
1490	/* If the creds don't match, we can't compound the layoutreturn */
1491	if (!layoutreturn || cred_fscmp(cred, lc_cred) != 0)
1492		goto out_noroc;
1493
1494	roc = layoutreturn;
1495	pnfs_init_layoutreturn_args(args, lo, &stateid, iomode);
1496	res->lrs_present = 0;
1497	layoutreturn = false;
1498	put_cred(lc_cred);
1499
1500out_noroc:
1501	spin_unlock(&ino->i_lock);
1502	rcu_read_unlock();
1503	pnfs_layoutcommit_inode(ino, true);
1504	if (roc) {
1505		struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1506		if (ld->prepare_layoutreturn)
1507			ld->prepare_layoutreturn(args);
1508		pnfs_put_layout_hdr(lo);
1509		return true;
1510	}
1511	if (layoutreturn)
1512		pnfs_send_layoutreturn(lo, &stateid, &lc_cred, iomode, true);
1513	pnfs_put_layout_hdr(lo);
1514	return false;
1515}
1516
1517int pnfs_roc_done(struct rpc_task *task, struct nfs4_layoutreturn_args **argpp,
1518		  struct nfs4_layoutreturn_res **respp, int *ret)
 
 
1519{
1520	struct nfs4_layoutreturn_args *arg = *argpp;
1521	int retval = -EAGAIN;
1522
1523	if (!arg)
1524		return 0;
1525	/* Handle Layoutreturn errors */
1526	switch (*ret) {
1527	case 0:
1528		retval = 0;
1529		break;
1530	case -NFS4ERR_NOMATCHING_LAYOUT:
1531		/* Was there an RPC level error? If not, retry */
1532		if (task->tk_rpc_status == 0)
1533			break;
1534		/* If the call was not sent, let caller handle it */
1535		if (!RPC_WAS_SENT(task))
1536			return 0;
1537		/*
1538		 * Otherwise, assume the call succeeded and
1539		 * that we need to release the layout
1540		 */
1541		*ret = 0;
1542		(*respp)->lrs_present = 0;
1543		retval = 0;
1544		break;
1545	case -NFS4ERR_DELAY:
1546		/* Let the caller handle the retry */
1547		*ret = -NFS4ERR_NOMATCHING_LAYOUT;
1548		return 0;
1549	case -NFS4ERR_OLD_STATEID:
1550		if (!nfs4_layout_refresh_old_stateid(&arg->stateid,
1551						     &arg->range, arg->inode))
1552			break;
1553		*ret = -NFS4ERR_NOMATCHING_LAYOUT;
1554		return -EAGAIN;
1555	}
1556	*argpp = NULL;
1557	*respp = NULL;
1558	return retval;
1559}
1560
1561void pnfs_roc_release(struct nfs4_layoutreturn_args *args,
1562		struct nfs4_layoutreturn_res *res,
1563		int ret)
1564{
1565	struct pnfs_layout_hdr *lo = args->layout;
1566	struct inode *inode = args->inode;
1567	const nfs4_stateid *res_stateid = NULL;
1568	struct nfs4_xdr_opaque_data *ld_private = args->ld_private;
1569
1570	switch (ret) {
1571	case -NFS4ERR_NOMATCHING_LAYOUT:
1572		spin_lock(&inode->i_lock);
1573		if (pnfs_layout_is_valid(lo) &&
1574		    nfs4_stateid_match_other(&args->stateid, &lo->plh_stateid))
1575			pnfs_set_plh_return_info(lo, args->range.iomode, 0);
1576		pnfs_clear_layoutreturn_waitbit(lo);
1577		spin_unlock(&inode->i_lock);
1578		break;
1579	case 0:
1580		if (res->lrs_present)
1581			res_stateid = &res->stateid;
1582		fallthrough;
1583	default:
1584		pnfs_layoutreturn_free_lsegs(lo, &args->stateid, &args->range,
1585					     res_stateid);
1586	}
1587	trace_nfs4_layoutreturn_on_close(args->inode, &args->stateid, ret);
 
1588	if (ld_private && ld_private->ops && ld_private->ops->free)
1589		ld_private->ops->free(ld_private);
1590	pnfs_put_layout_hdr(lo);
 
1591}
1592
1593bool pnfs_wait_on_layoutreturn(struct inode *ino, struct rpc_task *task)
1594{
1595	struct nfs_inode *nfsi = NFS_I(ino);
1596        struct pnfs_layout_hdr *lo;
1597        bool sleep = false;
1598
1599	/* we might not have grabbed lo reference. so need to check under
1600	 * i_lock */
1601        spin_lock(&ino->i_lock);
1602        lo = nfsi->layout;
1603        if (lo && test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
1604                rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
1605                sleep = true;
1606	}
1607        spin_unlock(&ino->i_lock);
1608        return sleep;
1609}
1610
1611/*
1612 * Compare two layout segments for sorting into layout cache.
1613 * We want to preferentially return RW over RO layouts, so ensure those
1614 * are seen first.
1615 */
1616static s64
1617pnfs_lseg_range_cmp(const struct pnfs_layout_range *l1,
1618	   const struct pnfs_layout_range *l2)
1619{
1620	s64 d;
1621
1622	/* high offset > low offset */
1623	d = l1->offset - l2->offset;
1624	if (d)
1625		return d;
1626
1627	/* short length > long length */
1628	d = l2->length - l1->length;
1629	if (d)
1630		return d;
1631
1632	/* read > read/write */
1633	return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
1634}
1635
1636static bool
1637pnfs_lseg_range_is_after(const struct pnfs_layout_range *l1,
1638		const struct pnfs_layout_range *l2)
1639{
1640	return pnfs_lseg_range_cmp(l1, l2) > 0;
1641}
1642
1643static bool
1644pnfs_lseg_no_merge(struct pnfs_layout_segment *lseg,
1645		struct pnfs_layout_segment *old)
1646{
1647	return false;
1648}
1649
1650void
1651pnfs_generic_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1652		   struct pnfs_layout_segment *lseg,
1653		   bool (*is_after)(const struct pnfs_layout_range *,
1654			   const struct pnfs_layout_range *),
1655		   bool (*do_merge)(struct pnfs_layout_segment *,
1656			   struct pnfs_layout_segment *),
1657		   struct list_head *free_me)
1658{
1659	struct pnfs_layout_segment *lp, *tmp;
1660
1661	dprintk("%s:Begin\n", __func__);
1662
1663	list_for_each_entry_safe(lp, tmp, &lo->plh_segs, pls_list) {
1664		if (test_bit(NFS_LSEG_VALID, &lp->pls_flags) == 0)
1665			continue;
1666		if (do_merge(lseg, lp)) {
1667			mark_lseg_invalid(lp, free_me);
1668			continue;
1669		}
1670		if (is_after(&lseg->pls_range, &lp->pls_range))
1671			continue;
1672		list_add_tail(&lseg->pls_list, &lp->pls_list);
1673		dprintk("%s: inserted lseg %p "
1674			"iomode %d offset %llu length %llu before "
1675			"lp %p iomode %d offset %llu length %llu\n",
1676			__func__, lseg, lseg->pls_range.iomode,
1677			lseg->pls_range.offset, lseg->pls_range.length,
1678			lp, lp->pls_range.iomode, lp->pls_range.offset,
1679			lp->pls_range.length);
1680		goto out;
1681	}
1682	list_add_tail(&lseg->pls_list, &lo->plh_segs);
1683	dprintk("%s: inserted lseg %p "
1684		"iomode %d offset %llu length %llu at tail\n",
1685		__func__, lseg, lseg->pls_range.iomode,
1686		lseg->pls_range.offset, lseg->pls_range.length);
1687out:
1688	pnfs_get_layout_hdr(lo);
1689
1690	dprintk("%s:Return\n", __func__);
1691}
1692EXPORT_SYMBOL_GPL(pnfs_generic_layout_insert_lseg);
1693
1694static void
1695pnfs_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1696		   struct pnfs_layout_segment *lseg,
1697		   struct list_head *free_me)
1698{
1699	struct inode *inode = lo->plh_inode;
1700	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
1701
1702	if (ld->add_lseg != NULL)
1703		ld->add_lseg(lo, lseg, free_me);
1704	else
1705		pnfs_generic_layout_insert_lseg(lo, lseg,
1706				pnfs_lseg_range_is_after,
1707				pnfs_lseg_no_merge,
1708				free_me);
1709}
1710
1711static struct pnfs_layout_hdr *
1712alloc_init_layout_hdr(struct inode *ino,
1713		      struct nfs_open_context *ctx,
1714		      gfp_t gfp_flags)
1715{
1716	struct pnfs_layout_hdr *lo;
1717
1718	lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
1719	if (!lo)
1720		return NULL;
1721	refcount_set(&lo->plh_refcount, 1);
1722	INIT_LIST_HEAD(&lo->plh_layouts);
1723	INIT_LIST_HEAD(&lo->plh_segs);
1724	INIT_LIST_HEAD(&lo->plh_return_segs);
1725	INIT_LIST_HEAD(&lo->plh_bulk_destroy);
1726	lo->plh_inode = ino;
1727	lo->plh_lc_cred = get_cred(ctx->cred);
1728	lo->plh_flags |= 1 << NFS_LAYOUT_INVALID_STID;
1729	return lo;
1730}
1731
1732static struct pnfs_layout_hdr *
1733pnfs_find_alloc_layout(struct inode *ino,
1734		       struct nfs_open_context *ctx,
1735		       gfp_t gfp_flags)
1736	__releases(&ino->i_lock)
1737	__acquires(&ino->i_lock)
1738{
1739	struct nfs_inode *nfsi = NFS_I(ino);
1740	struct pnfs_layout_hdr *new = NULL;
1741
1742	dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
1743
1744	if (nfsi->layout != NULL)
1745		goto out_existing;
1746	spin_unlock(&ino->i_lock);
1747	new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
1748	spin_lock(&ino->i_lock);
1749
1750	if (likely(nfsi->layout == NULL)) {	/* Won the race? */
1751		nfsi->layout = new;
1752		return new;
1753	} else if (new != NULL)
1754		pnfs_free_layout_hdr(new);
1755out_existing:
1756	pnfs_get_layout_hdr(nfsi->layout);
1757	return nfsi->layout;
1758}
1759
1760/*
1761 * iomode matching rules:
1762 * iomode	lseg	strict match
1763 *                      iomode
1764 * -----	-----	------ -----
1765 * ANY		READ	N/A    true
1766 * ANY		RW	N/A    true
1767 * RW		READ	N/A    false
1768 * RW		RW	N/A    true
1769 * READ		READ	N/A    true
1770 * READ		RW	true   false
1771 * READ		RW	false  true
1772 */
1773static bool
1774pnfs_lseg_range_match(const struct pnfs_layout_range *ls_range,
1775		 const struct pnfs_layout_range *range,
1776		 bool strict_iomode)
1777{
1778	struct pnfs_layout_range range1;
1779
1780	if ((range->iomode == IOMODE_RW &&
1781	     ls_range->iomode != IOMODE_RW) ||
1782	    (range->iomode != ls_range->iomode &&
1783	     strict_iomode) ||
1784	    !pnfs_lseg_range_intersecting(ls_range, range))
1785		return false;
1786
1787	/* range1 covers only the first byte in the range */
1788	range1 = *range;
1789	range1.length = 1;
1790	return pnfs_lseg_range_contained(ls_range, &range1);
1791}
1792
1793/*
1794 * lookup range in layout
1795 */
1796static struct pnfs_layout_segment *
1797pnfs_find_lseg(struct pnfs_layout_hdr *lo,
1798		struct pnfs_layout_range *range,
1799		bool strict_iomode)
1800{
1801	struct pnfs_layout_segment *lseg, *ret = NULL;
1802
1803	dprintk("%s:Begin\n", __func__);
1804
1805	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
1806		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
1807		    pnfs_lseg_range_match(&lseg->pls_range, range,
1808					  strict_iomode)) {
1809			ret = pnfs_get_lseg(lseg);
1810			break;
1811		}
1812	}
1813
1814	dprintk("%s:Return lseg %p ref %d\n",
1815		__func__, ret, ret ? refcount_read(&ret->pls_refcount) : 0);
1816	return ret;
1817}
1818
1819/*
1820 * Use mdsthreshold hints set at each OPEN to determine if I/O should go
1821 * to the MDS or over pNFS
1822 *
1823 * The nfs_inode read_io and write_io fields are cumulative counters reset
1824 * when there are no layout segments. Note that in pnfs_update_layout iomode
1825 * is set to IOMODE_READ for a READ request, and set to IOMODE_RW for a
1826 * WRITE request.
1827 *
1828 * A return of true means use MDS I/O.
1829 *
1830 * From rfc 5661:
1831 * If a file's size is smaller than the file size threshold, data accesses
1832 * SHOULD be sent to the metadata server.  If an I/O request has a length that
1833 * is below the I/O size threshold, the I/O SHOULD be sent to the metadata
1834 * server.  If both file size and I/O size are provided, the client SHOULD
1835 * reach or exceed  both thresholds before sending its read or write
1836 * requests to the data server.
1837 */
1838static bool pnfs_within_mdsthreshold(struct nfs_open_context *ctx,
1839				     struct inode *ino, int iomode)
1840{
1841	struct nfs4_threshold *t = ctx->mdsthreshold;
1842	struct nfs_inode *nfsi = NFS_I(ino);
1843	loff_t fsize = i_size_read(ino);
1844	bool size = false, size_set = false, io = false, io_set = false, ret = false;
1845
1846	if (t == NULL)
1847		return ret;
1848
1849	dprintk("%s bm=0x%x rd_sz=%llu wr_sz=%llu rd_io=%llu wr_io=%llu\n",
1850		__func__, t->bm, t->rd_sz, t->wr_sz, t->rd_io_sz, t->wr_io_sz);
1851
1852	switch (iomode) {
1853	case IOMODE_READ:
1854		if (t->bm & THRESHOLD_RD) {
1855			dprintk("%s fsize %llu\n", __func__, fsize);
1856			size_set = true;
1857			if (fsize < t->rd_sz)
1858				size = true;
1859		}
1860		if (t->bm & THRESHOLD_RD_IO) {
1861			dprintk("%s nfsi->read_io %llu\n", __func__,
1862				nfsi->read_io);
1863			io_set = true;
1864			if (nfsi->read_io < t->rd_io_sz)
1865				io = true;
1866		}
1867		break;
1868	case IOMODE_RW:
1869		if (t->bm & THRESHOLD_WR) {
1870			dprintk("%s fsize %llu\n", __func__, fsize);
1871			size_set = true;
1872			if (fsize < t->wr_sz)
1873				size = true;
1874		}
1875		if (t->bm & THRESHOLD_WR_IO) {
1876			dprintk("%s nfsi->write_io %llu\n", __func__,
1877				nfsi->write_io);
1878			io_set = true;
1879			if (nfsi->write_io < t->wr_io_sz)
1880				io = true;
1881		}
1882		break;
1883	}
1884	if (size_set && io_set) {
1885		if (size && io)
1886			ret = true;
1887	} else if (size || io)
1888		ret = true;
1889
1890	dprintk("<-- %s size %d io %d ret %d\n", __func__, size, io, ret);
1891	return ret;
1892}
1893
1894static int pnfs_prepare_to_retry_layoutget(struct pnfs_layout_hdr *lo)
1895{
1896	/*
1897	 * send layoutcommit as it can hold up layoutreturn due to lseg
1898	 * reference
1899	 */
1900	pnfs_layoutcommit_inode(lo->plh_inode, false);
1901	return wait_on_bit_action(&lo->plh_flags, NFS_LAYOUT_RETURN,
1902				   nfs_wait_bit_killable,
1903				   TASK_KILLABLE);
1904}
1905
1906static void nfs_layoutget_begin(struct pnfs_layout_hdr *lo)
1907{
1908	atomic_inc(&lo->plh_outstanding);
1909}
1910
1911static void nfs_layoutget_end(struct pnfs_layout_hdr *lo)
1912{
1913	if (atomic_dec_and_test(&lo->plh_outstanding))
1914		wake_up_var(&lo->plh_outstanding);
1915}
1916
1917static bool pnfs_is_first_layoutget(struct pnfs_layout_hdr *lo)
1918{
1919	return test_bit(NFS_LAYOUT_FIRST_LAYOUTGET, &lo->plh_flags);
1920}
1921
1922static void pnfs_clear_first_layoutget(struct pnfs_layout_hdr *lo)
1923{
1924	unsigned long *bitlock = &lo->plh_flags;
1925
1926	clear_bit_unlock(NFS_LAYOUT_FIRST_LAYOUTGET, bitlock);
1927	smp_mb__after_atomic();
1928	wake_up_bit(bitlock, NFS_LAYOUT_FIRST_LAYOUTGET);
1929}
1930
1931static void _add_to_server_list(struct pnfs_layout_hdr *lo,
1932				struct nfs_server *server)
1933{
1934	if (!test_and_set_bit(NFS_LAYOUT_HASHED, &lo->plh_flags)) {
1935		struct nfs_client *clp = server->nfs_client;
1936
1937		/* The lo must be on the clp list if there is any
1938		 * chance of a CB_LAYOUTRECALL(FILE) coming in.
1939		 */
1940		spin_lock(&clp->cl_lock);
1941		list_add_tail_rcu(&lo->plh_layouts, &server->layouts);
 
1942		spin_unlock(&clp->cl_lock);
1943	}
1944}
1945
1946/*
1947 * Layout segment is retreived from the server if not cached.
1948 * The appropriate layout segment is referenced and returned to the caller.
1949 */
1950struct pnfs_layout_segment *
1951pnfs_update_layout(struct inode *ino,
1952		   struct nfs_open_context *ctx,
1953		   loff_t pos,
1954		   u64 count,
1955		   enum pnfs_iomode iomode,
1956		   bool strict_iomode,
1957		   gfp_t gfp_flags)
1958{
1959	struct pnfs_layout_range arg = {
1960		.iomode = iomode,
1961		.offset = pos,
1962		.length = count,
1963	};
1964	unsigned pg_offset;
1965	struct nfs_server *server = NFS_SERVER(ino);
1966	struct nfs_client *clp = server->nfs_client;
1967	struct pnfs_layout_hdr *lo = NULL;
1968	struct pnfs_layout_segment *lseg = NULL;
1969	struct nfs4_layoutget *lgp;
1970	nfs4_stateid stateid;
1971	long timeout = 0;
1972	unsigned long giveup = jiffies + (clp->cl_lease_time << 1);
1973	bool first;
1974
1975	if (!pnfs_enabled_sb(NFS_SERVER(ino))) {
1976		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1977				 PNFS_UPDATE_LAYOUT_NO_PNFS);
1978		goto out;
1979	}
1980
1981	if (pnfs_within_mdsthreshold(ctx, ino, iomode)) {
1982		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1983				 PNFS_UPDATE_LAYOUT_MDSTHRESH);
1984		goto out;
1985	}
1986
1987lookup_again:
1988	lseg = ERR_PTR(nfs4_client_recover_expired_lease(clp));
1989	if (IS_ERR(lseg))
1990		goto out;
1991	first = false;
1992	spin_lock(&ino->i_lock);
1993	lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
1994	if (lo == NULL) {
1995		spin_unlock(&ino->i_lock);
1996		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1997				 PNFS_UPDATE_LAYOUT_NOMEM);
1998		goto out;
1999	}
2000
2001	/* Do we even need to bother with this? */
2002	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
2003		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2004				 PNFS_UPDATE_LAYOUT_BULK_RECALL);
2005		dprintk("%s matches recall, use MDS\n", __func__);
2006		goto out_unlock;
2007	}
2008
2009	/* if LAYOUTGET already failed once we don't try again */
2010	if (pnfs_layout_io_test_failed(lo, iomode)) {
2011		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2012				 PNFS_UPDATE_LAYOUT_IO_TEST_FAIL);
2013		goto out_unlock;
2014	}
2015
2016	/*
2017	 * If the layout segment list is empty, but there are outstanding
2018	 * layoutget calls, then they might be subject to a layoutrecall.
2019	 */
2020	if ((list_empty(&lo->plh_segs) || !pnfs_layout_is_valid(lo)) &&
2021	    atomic_read(&lo->plh_outstanding) != 0) {
2022		spin_unlock(&ino->i_lock);
2023		lseg = ERR_PTR(wait_var_event_killable(&lo->plh_outstanding,
2024					!atomic_read(&lo->plh_outstanding)));
2025		if (IS_ERR(lseg))
2026			goto out_put_layout_hdr;
2027		pnfs_put_layout_hdr(lo);
2028		goto lookup_again;
2029	}
2030
2031	/*
2032	 * Because we free lsegs when sending LAYOUTRETURN, we need to wait
2033	 * for LAYOUTRETURN.
2034	 */
2035	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
2036		spin_unlock(&ino->i_lock);
2037		dprintk("%s wait for layoutreturn\n", __func__);
2038		lseg = ERR_PTR(pnfs_prepare_to_retry_layoutget(lo));
2039		if (!IS_ERR(lseg)) {
2040			pnfs_put_layout_hdr(lo);
2041			dprintk("%s retrying\n", __func__);
2042			trace_pnfs_update_layout(ino, pos, count, iomode, lo,
2043						 lseg,
2044						 PNFS_UPDATE_LAYOUT_RETRY);
2045			goto lookup_again;
2046		}
2047		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2048					 PNFS_UPDATE_LAYOUT_RETURN);
2049		goto out_put_layout_hdr;
2050	}
2051
2052	lseg = pnfs_find_lseg(lo, &arg, strict_iomode);
2053	if (lseg) {
2054		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2055				PNFS_UPDATE_LAYOUT_FOUND_CACHED);
2056		goto out_unlock;
2057	}
2058
2059	/*
2060	 * Choose a stateid for the LAYOUTGET. If we don't have a layout
2061	 * stateid, or it has been invalidated, then we must use the open
2062	 * stateid.
2063	 */
2064	if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags)) {
2065		int status;
2066
2067		/*
2068		 * The first layoutget for the file. Need to serialize per
2069		 * RFC 5661 Errata 3208.
2070		 */
2071		if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET,
2072				     &lo->plh_flags)) {
2073			spin_unlock(&ino->i_lock);
2074			lseg = ERR_PTR(wait_on_bit(&lo->plh_flags,
2075						NFS_LAYOUT_FIRST_LAYOUTGET,
2076						TASK_KILLABLE));
2077			if (IS_ERR(lseg))
2078				goto out_put_layout_hdr;
2079			pnfs_put_layout_hdr(lo);
2080			dprintk("%s retrying\n", __func__);
2081			goto lookup_again;
2082		}
2083
2084		spin_unlock(&ino->i_lock);
2085		first = true;
2086		status = nfs4_select_rw_stateid(ctx->state,
2087					iomode == IOMODE_RW ? FMODE_WRITE : FMODE_READ,
2088					NULL, &stateid, NULL);
2089		if (status != 0) {
2090			lseg = ERR_PTR(status);
2091			trace_pnfs_update_layout(ino, pos, count,
2092					iomode, lo, lseg,
2093					PNFS_UPDATE_LAYOUT_INVALID_OPEN);
 
 
 
2094			nfs4_schedule_stateid_recovery(server, ctx->state);
2095			pnfs_clear_first_layoutget(lo);
2096			pnfs_put_layout_hdr(lo);
2097			goto lookup_again;
2098		}
2099		spin_lock(&ino->i_lock);
2100	} else {
2101		nfs4_stateid_copy(&stateid, &lo->plh_stateid);
2102	}
2103
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2104	if (pnfs_layoutgets_blocked(lo)) {
2105		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2106				PNFS_UPDATE_LAYOUT_BLOCKED);
2107		goto out_unlock;
2108	}
2109	nfs_layoutget_begin(lo);
2110	spin_unlock(&ino->i_lock);
2111
2112	_add_to_server_list(lo, server);
2113
2114	pg_offset = arg.offset & ~PAGE_MASK;
2115	if (pg_offset) {
2116		arg.offset -= pg_offset;
2117		arg.length += pg_offset;
2118	}
2119	if (arg.length != NFS4_MAX_UINT64)
2120		arg.length = PAGE_ALIGN(arg.length);
2121
2122	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &stateid, &arg, gfp_flags);
2123	if (!lgp) {
2124		trace_pnfs_update_layout(ino, pos, count, iomode, lo, NULL,
2125					 PNFS_UPDATE_LAYOUT_NOMEM);
2126		nfs_layoutget_end(lo);
2127		goto out_put_layout_hdr;
2128	}
2129
2130	lgp->lo = lo;
2131	pnfs_get_layout_hdr(lo);
2132
2133	lseg = nfs4_proc_layoutget(lgp, &timeout);
2134	trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2135				 PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET);
2136	nfs_layoutget_end(lo);
2137	if (IS_ERR(lseg)) {
2138		switch(PTR_ERR(lseg)) {
2139		case -EBUSY:
2140			if (time_after(jiffies, giveup))
2141				lseg = NULL;
2142			break;
2143		case -ERECALLCONFLICT:
2144		case -EAGAIN:
2145			break;
2146		default:
2147			if (!nfs_error_is_fatal(PTR_ERR(lseg))) {
2148				pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2149				lseg = NULL;
2150			}
2151			goto out_put_layout_hdr;
2152		}
2153		if (lseg) {
2154			if (first)
2155				pnfs_clear_first_layoutget(lo);
2156			trace_pnfs_update_layout(ino, pos, count,
2157				iomode, lo, lseg, PNFS_UPDATE_LAYOUT_RETRY);
2158			pnfs_put_layout_hdr(lo);
2159			goto lookup_again;
2160		}
2161	} else {
2162		pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2163	}
2164
2165out_put_layout_hdr:
2166	if (first)
2167		pnfs_clear_first_layoutget(lo);
2168	trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2169				 PNFS_UPDATE_LAYOUT_EXIT);
2170	pnfs_put_layout_hdr(lo);
2171out:
2172	dprintk("%s: inode %s/%llu pNFS layout segment %s for "
2173			"(%s, offset: %llu, length: %llu)\n",
2174			__func__, ino->i_sb->s_id,
2175			(unsigned long long)NFS_FILEID(ino),
2176			IS_ERR_OR_NULL(lseg) ? "not found" : "found",
2177			iomode==IOMODE_RW ?  "read/write" : "read-only",
2178			(unsigned long long)pos,
2179			(unsigned long long)count);
2180	return lseg;
2181out_unlock:
2182	spin_unlock(&ino->i_lock);
2183	goto out_put_layout_hdr;
2184}
2185EXPORT_SYMBOL_GPL(pnfs_update_layout);
2186
2187static bool
2188pnfs_sanity_check_layout_range(struct pnfs_layout_range *range)
2189{
2190	switch (range->iomode) {
2191	case IOMODE_READ:
2192	case IOMODE_RW:
2193		break;
2194	default:
2195		return false;
2196	}
2197	if (range->offset == NFS4_MAX_UINT64)
2198		return false;
2199	if (range->length == 0)
2200		return false;
2201	if (range->length != NFS4_MAX_UINT64 &&
2202	    range->length > NFS4_MAX_UINT64 - range->offset)
2203		return false;
2204	return true;
2205}
2206
2207static struct pnfs_layout_hdr *
2208_pnfs_grab_empty_layout(struct inode *ino, struct nfs_open_context *ctx)
2209{
2210	struct pnfs_layout_hdr *lo;
2211
2212	spin_lock(&ino->i_lock);
2213	lo = pnfs_find_alloc_layout(ino, ctx, GFP_KERNEL);
2214	if (!lo)
2215		goto out_unlock;
2216	if (!test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags))
2217		goto out_unlock;
2218	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
2219		goto out_unlock;
2220	if (pnfs_layoutgets_blocked(lo))
2221		goto out_unlock;
2222	if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET, &lo->plh_flags))
2223		goto out_unlock;
2224	nfs_layoutget_begin(lo);
2225	spin_unlock(&ino->i_lock);
2226	_add_to_server_list(lo, NFS_SERVER(ino));
2227	return lo;
2228
2229out_unlock:
2230	spin_unlock(&ino->i_lock);
2231	pnfs_put_layout_hdr(lo);
2232	return NULL;
2233}
2234
 
 
2235static void _lgopen_prepare_attached(struct nfs4_opendata *data,
2236				     struct nfs_open_context *ctx)
2237{
2238	struct inode *ino = data->dentry->d_inode;
2239	struct pnfs_layout_range rng = {
2240		.iomode = (data->o_arg.fmode & FMODE_WRITE) ?
2241			  IOMODE_RW: IOMODE_READ,
2242		.offset = 0,
2243		.length = NFS4_MAX_UINT64,
2244	};
2245	struct nfs4_layoutget *lgp;
2246	struct pnfs_layout_hdr *lo;
2247
2248	/* Heuristic: don't send layoutget if we have cached data */
2249	if (rng.iomode == IOMODE_READ &&
2250	   (i_size_read(ino) == 0 || ino->i_mapping->nrpages != 0))
2251		return;
2252
2253	lo = _pnfs_grab_empty_layout(ino, ctx);
2254	if (!lo)
2255		return;
2256	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &current_stateid,
2257					     &rng, GFP_KERNEL);
2258	if (!lgp) {
2259		pnfs_clear_first_layoutget(lo);
2260		nfs_layoutget_end(lo);
2261		pnfs_put_layout_hdr(lo);
2262		return;
2263	}
2264	lgp->lo = lo;
2265	data->lgp = lgp;
2266	data->o_arg.lg_args = &lgp->args;
2267	data->o_res.lg_res = &lgp->res;
2268}
2269
2270static void _lgopen_prepare_floating(struct nfs4_opendata *data,
2271				     struct nfs_open_context *ctx)
2272{
2273	struct inode *ino = data->dentry->d_inode;
2274	struct pnfs_layout_range rng = {
2275		.iomode = (data->o_arg.fmode & FMODE_WRITE) ?
2276			  IOMODE_RW: IOMODE_READ,
2277		.offset = 0,
2278		.length = NFS4_MAX_UINT64,
2279	};
2280	struct nfs4_layoutget *lgp;
2281
2282	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &current_stateid,
2283					     &rng, GFP_KERNEL);
2284	if (!lgp)
2285		return;
2286	data->lgp = lgp;
2287	data->o_arg.lg_args = &lgp->args;
2288	data->o_res.lg_res = &lgp->res;
2289}
2290
2291void pnfs_lgopen_prepare(struct nfs4_opendata *data,
2292			 struct nfs_open_context *ctx)
2293{
2294	struct nfs_server *server = NFS_SERVER(data->dir->d_inode);
2295
2296	if (!(pnfs_enabled_sb(server) &&
2297	      server->pnfs_curr_ld->flags & PNFS_LAYOUTGET_ON_OPEN))
2298		return;
2299	/* Could check on max_ops, but currently hardcoded high enough */
2300	if (!nfs_server_capable(data->dir->d_inode, NFS_CAP_LGOPEN))
2301		return;
2302	if (data->lgp)
2303		return;
2304	if (data->state)
2305		_lgopen_prepare_attached(data, ctx);
2306	else
2307		_lgopen_prepare_floating(data, ctx);
2308}
2309
2310void pnfs_parse_lgopen(struct inode *ino, struct nfs4_layoutget *lgp,
2311		       struct nfs_open_context *ctx)
2312{
2313	struct pnfs_layout_hdr *lo;
2314	struct pnfs_layout_segment *lseg;
2315	struct nfs_server *srv = NFS_SERVER(ino);
2316	u32 iomode;
2317
2318	if (!lgp)
2319		return;
2320	dprintk("%s: entered with status %i\n", __func__, lgp->res.status);
2321	if (lgp->res.status) {
2322		switch (lgp->res.status) {
2323		default:
2324			break;
2325		/*
2326		 * Halt lgopen attempts if the server doesn't recognise
2327		 * the "current stateid" value, the layout type, or the
2328		 * layoutget operation as being valid.
2329		 * Also if it complains about too many ops in the compound
2330		 * or of the request/reply being too big.
2331		 */
2332		case -NFS4ERR_BAD_STATEID:
2333		case -NFS4ERR_NOTSUPP:
2334		case -NFS4ERR_REP_TOO_BIG:
2335		case -NFS4ERR_REP_TOO_BIG_TO_CACHE:
2336		case -NFS4ERR_REQ_TOO_BIG:
2337		case -NFS4ERR_TOO_MANY_OPS:
2338		case -NFS4ERR_UNKNOWN_LAYOUTTYPE:
2339			srv->caps &= ~NFS_CAP_LGOPEN;
2340		}
2341		return;
2342	}
2343	if (!lgp->lo) {
2344		lo = _pnfs_grab_empty_layout(ino, ctx);
2345		if (!lo)
2346			return;
2347		lgp->lo = lo;
2348	} else
2349		lo = lgp->lo;
2350
2351	lseg = pnfs_layout_process(lgp);
2352	if (!IS_ERR(lseg)) {
2353		iomode = lgp->args.range.iomode;
2354		pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2355		pnfs_put_lseg(lseg);
2356	}
2357}
2358
2359void nfs4_lgopen_release(struct nfs4_layoutget *lgp)
2360{
2361	if (lgp != NULL) {
2362		if (lgp->lo) {
2363			pnfs_clear_first_layoutget(lgp->lo);
2364			nfs_layoutget_end(lgp->lo);
 
 
2365		}
2366		pnfs_layoutget_free(lgp);
2367	}
2368}
2369
2370struct pnfs_layout_segment *
2371pnfs_layout_process(struct nfs4_layoutget *lgp)
2372{
2373	struct pnfs_layout_hdr *lo = lgp->lo;
2374	struct nfs4_layoutget_res *res = &lgp->res;
2375	struct pnfs_layout_segment *lseg;
2376	struct inode *ino = lo->plh_inode;
2377	LIST_HEAD(free_me);
2378
2379	if (!pnfs_sanity_check_layout_range(&res->range))
2380		return ERR_PTR(-EINVAL);
2381
2382	/* Inject layout blob into I/O device driver */
2383	lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
2384	if (IS_ERR_OR_NULL(lseg)) {
2385		if (!lseg)
2386			lseg = ERR_PTR(-ENOMEM);
2387
2388		dprintk("%s: Could not allocate layout: error %ld\n",
2389		       __func__, PTR_ERR(lseg));
2390		return lseg;
2391	}
2392
2393	pnfs_init_lseg(lo, lseg, &res->range, &res->stateid);
2394
2395	spin_lock(&ino->i_lock);
2396	if (pnfs_layoutgets_blocked(lo)) {
2397		dprintk("%s forget reply due to state\n", __func__);
2398		goto out_forget;
2399	}
2400
2401	if (!pnfs_layout_is_valid(lo) && !pnfs_is_first_layoutget(lo))
2402		goto out_forget;
2403
2404	if (nfs4_stateid_match_other(&lo->plh_stateid, &res->stateid)) {
2405		/* existing state ID, make sure the sequence number matches. */
2406		if (pnfs_layout_stateid_blocked(lo, &res->stateid)) {
2407			if (!pnfs_layout_is_valid(lo))
2408				lo->plh_barrier = 0;
2409			dprintk("%s forget reply due to sequence\n", __func__);
2410			goto out_forget;
2411		}
2412		pnfs_set_layout_stateid(lo, &res->stateid, lgp->cred, false);
2413	} else if (pnfs_layout_is_valid(lo)) {
2414		/*
2415		 * We got an entirely new state ID.  Mark all segments for the
2416		 * inode invalid, and retry the layoutget
2417		 */
2418		struct pnfs_layout_range range = {
2419			.iomode = IOMODE_ANY,
2420			.length = NFS4_MAX_UINT64,
2421		};
2422		pnfs_mark_matching_lsegs_return(lo, &free_me, &range, 0);
2423		goto out_forget;
2424	} else {
2425		/* We have a completely new layout */
2426		pnfs_set_layout_stateid(lo, &res->stateid, lgp->cred, true);
2427	}
2428
2429	pnfs_get_lseg(lseg);
2430	pnfs_layout_insert_lseg(lo, lseg, &free_me);
2431
2432
2433	if (res->return_on_close)
2434		set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
2435
2436	spin_unlock(&ino->i_lock);
2437	pnfs_free_lseg_list(&free_me);
2438	return lseg;
2439
2440out_forget:
2441	spin_unlock(&ino->i_lock);
2442	lseg->pls_layout = lo;
2443	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
2444	return ERR_PTR(-EAGAIN);
2445}
2446
 
 
 
 
 
 
 
 
 
 
2447/**
2448 * pnfs_mark_matching_lsegs_return - Free or return matching layout segments
2449 * @lo: pointer to layout header
2450 * @tmp_list: list header to be used with pnfs_free_lseg_list()
2451 * @return_range: describe layout segment ranges to be returned
2452 * @seq: stateid seqid to match
2453 *
2454 * This function is mainly intended for use by layoutrecall. It attempts
2455 * to free the layout segment immediately, or else to mark it for return
2456 * as soon as its reference count drops to zero.
2457 *
2458 * Returns
2459 * - 0: a layoutreturn needs to be scheduled.
2460 * - EBUSY: there are layout segment that are still in use.
2461 * - ENOENT: there are no layout segments that need to be returned.
2462 */
2463int
2464pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
2465				struct list_head *tmp_list,
2466				const struct pnfs_layout_range *return_range,
2467				u32 seq)
2468{
2469	struct pnfs_layout_segment *lseg, *next;
2470	int remaining = 0;
2471
2472	dprintk("%s:Begin lo %p\n", __func__, lo);
2473
2474	assert_spin_locked(&lo->plh_inode->i_lock);
2475
2476	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
2477		tmp_list = &lo->plh_return_segs;
2478
2479	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
2480		if (pnfs_match_lseg_recall(lseg, return_range, seq)) {
2481			dprintk("%s: marking lseg %p iomode %d "
2482				"offset %llu length %llu\n", __func__,
2483				lseg, lseg->pls_range.iomode,
2484				lseg->pls_range.offset,
2485				lseg->pls_range.length);
2486			if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
2487				tmp_list = &lo->plh_return_segs;
2488			if (mark_lseg_invalid(lseg, tmp_list))
2489				continue;
2490			remaining++;
2491			set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
2492		}
2493
2494	if (remaining) {
2495		pnfs_set_plh_return_info(lo, return_range->iomode, seq);
2496		return -EBUSY;
2497	}
2498
2499	if (!list_empty(&lo->plh_return_segs)) {
2500		pnfs_set_plh_return_info(lo, return_range->iomode, seq);
2501		return 0;
2502	}
2503
2504	return -ENOENT;
2505}
2506
2507static void
2508pnfs_mark_layout_for_return(struct inode *inode,
2509			    const struct pnfs_layout_range *range)
2510{
2511	struct pnfs_layout_hdr *lo;
 
 
 
 
 
2512	bool return_now = false;
2513
2514	spin_lock(&inode->i_lock);
2515	lo = NFS_I(inode)->layout;
2516	if (!pnfs_layout_is_valid(lo)) {
2517		spin_unlock(&inode->i_lock);
2518		return;
2519	}
2520	pnfs_set_plh_return_info(lo, range->iomode, 0);
2521	/*
2522	 * mark all matching lsegs so that we are sure to have no live
2523	 * segments at hand when sending layoutreturn. See pnfs_put_lseg()
2524	 * for how it works.
2525	 */
2526	if (pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs, range, 0) != -EBUSY) {
2527		const struct cred *cred;
2528		nfs4_stateid stateid;
2529		enum pnfs_iomode iomode;
2530
2531		return_now = pnfs_prepare_layoutreturn(lo, &stateid, &cred, &iomode);
2532		spin_unlock(&inode->i_lock);
2533		if (return_now)
2534			pnfs_send_layoutreturn(lo, &stateid, &cred, iomode, false);
2535	} else {
2536		spin_unlock(&inode->i_lock);
2537		nfs_commit_inode(inode, 0);
2538	}
2539}
2540
2541void pnfs_error_mark_layout_for_return(struct inode *inode,
2542				       struct pnfs_layout_segment *lseg)
2543{
2544	struct pnfs_layout_range range = {
2545		.iomode = lseg->pls_range.iomode,
2546		.offset = 0,
2547		.length = NFS4_MAX_UINT64,
2548	};
2549
2550	pnfs_mark_layout_for_return(inode, &range);
2551}
2552EXPORT_SYMBOL_GPL(pnfs_error_mark_layout_for_return);
2553
2554static bool
2555pnfs_layout_can_be_returned(struct pnfs_layout_hdr *lo)
2556{
2557	return pnfs_layout_is_valid(lo) &&
2558		!test_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags) &&
2559		!test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
2560}
2561
2562static struct pnfs_layout_segment *
2563pnfs_find_first_lseg(struct pnfs_layout_hdr *lo,
2564		     const struct pnfs_layout_range *range,
2565		     enum pnfs_iomode iomode)
2566{
2567	struct pnfs_layout_segment *lseg;
2568
2569	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
2570		if (!test_bit(NFS_LSEG_VALID, &lseg->pls_flags))
2571			continue;
2572		if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
2573			continue;
2574		if (lseg->pls_range.iomode != iomode && iomode != IOMODE_ANY)
2575			continue;
2576		if (pnfs_lseg_range_intersecting(&lseg->pls_range, range))
2577			return lseg;
2578	}
2579	return NULL;
2580}
2581
2582/* Find open file states whose mode matches that of the range */
2583static bool
2584pnfs_should_return_unused_layout(struct pnfs_layout_hdr *lo,
2585				 const struct pnfs_layout_range *range)
2586{
2587	struct list_head *head;
2588	struct nfs_open_context *ctx;
2589	fmode_t mode = 0;
2590
2591	if (!pnfs_layout_can_be_returned(lo) ||
2592	    !pnfs_find_first_lseg(lo, range, range->iomode))
2593		return false;
2594
2595	head = &NFS_I(lo->plh_inode)->open_files;
2596	list_for_each_entry_rcu(ctx, head, list) {
2597		if (ctx->state)
2598			mode |= ctx->state->state & (FMODE_READ|FMODE_WRITE);
2599	}
2600
2601	switch (range->iomode) {
2602	default:
2603		break;
2604	case IOMODE_READ:
2605		mode &= ~FMODE_WRITE;
2606		break;
2607	case IOMODE_RW:
2608		if (pnfs_find_first_lseg(lo, range, IOMODE_READ))
2609			mode &= ~FMODE_READ;
2610	}
2611	return mode == 0;
2612}
2613
2614static int
2615pnfs_layout_return_unused_byserver(struct nfs_server *server, void *data)
2616{
2617	const struct pnfs_layout_range *range = data;
2618	struct pnfs_layout_hdr *lo;
2619	struct inode *inode;
2620restart:
2621	rcu_read_lock();
2622	list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
2623		if (!pnfs_layout_can_be_returned(lo) ||
2624		    test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
2625			continue;
2626		inode = lo->plh_inode;
2627		spin_lock(&inode->i_lock);
2628		if (!pnfs_should_return_unused_layout(lo, range)) {
2629			spin_unlock(&inode->i_lock);
2630			continue;
2631		}
2632		spin_unlock(&inode->i_lock);
2633		inode = pnfs_grab_inode_layout_hdr(lo);
2634		if (!inode)
2635			continue;
2636		rcu_read_unlock();
2637		pnfs_mark_layout_for_return(inode, range);
2638		iput(inode);
2639		cond_resched();
2640		goto restart;
2641	}
2642	rcu_read_unlock();
2643	return 0;
2644}
2645
2646void
2647pnfs_layout_return_unused_byclid(struct nfs_client *clp,
2648				 enum pnfs_iomode iomode)
2649{
2650	struct pnfs_layout_range range = {
2651		.iomode = iomode,
2652		.offset = 0,
2653		.length = NFS4_MAX_UINT64,
2654	};
2655
2656	nfs_client_for_each_server(clp, pnfs_layout_return_unused_byserver,
2657			&range);
2658}
2659
2660void
2661pnfs_generic_pg_check_layout(struct nfs_pageio_descriptor *pgio)
2662{
2663	if (pgio->pg_lseg == NULL ||
2664	    test_bit(NFS_LSEG_VALID, &pgio->pg_lseg->pls_flags))
2665		return;
2666	pnfs_put_lseg(pgio->pg_lseg);
2667	pgio->pg_lseg = NULL;
2668}
2669EXPORT_SYMBOL_GPL(pnfs_generic_pg_check_layout);
2670
2671/*
2672 * Check for any intersection between the request and the pgio->pg_lseg,
2673 * and if none, put this pgio->pg_lseg away.
2674 */
2675void
2676pnfs_generic_pg_check_range(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
2677{
2678	if (pgio->pg_lseg && !pnfs_lseg_request_intersecting(pgio->pg_lseg, req)) {
2679		pnfs_put_lseg(pgio->pg_lseg);
2680		pgio->pg_lseg = NULL;
2681	}
2682}
2683EXPORT_SYMBOL_GPL(pnfs_generic_pg_check_range);
2684
2685void
2686pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
2687{
2688	u64 rd_size;
2689
2690	pnfs_generic_pg_check_layout(pgio);
2691	pnfs_generic_pg_check_range(pgio, req);
2692	if (pgio->pg_lseg == NULL) {
2693		if (pgio->pg_dreq == NULL)
2694			rd_size = i_size_read(pgio->pg_inode) - req_offset(req);
2695		else
2696			rd_size = nfs_dreq_bytes_left(pgio->pg_dreq);
2697
2698		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
2699						   nfs_req_openctx(req),
2700						   req_offset(req),
2701						   rd_size,
2702						   IOMODE_READ,
2703						   false,
2704						   GFP_KERNEL);
2705		if (IS_ERR(pgio->pg_lseg)) {
2706			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2707			pgio->pg_lseg = NULL;
2708			return;
2709		}
2710	}
2711	/* If no lseg, fall back to read through mds */
2712	if (pgio->pg_lseg == NULL)
2713		nfs_pageio_reset_read_mds(pgio);
2714
2715}
2716EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);
2717
2718void
2719pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
2720			   struct nfs_page *req, u64 wb_size)
2721{
2722	pnfs_generic_pg_check_layout(pgio);
2723	pnfs_generic_pg_check_range(pgio, req);
2724	if (pgio->pg_lseg == NULL) {
2725		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
2726						   nfs_req_openctx(req),
2727						   req_offset(req),
2728						   wb_size,
2729						   IOMODE_RW,
2730						   false,
2731						   GFP_KERNEL);
2732		if (IS_ERR(pgio->pg_lseg)) {
2733			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2734			pgio->pg_lseg = NULL;
2735			return;
2736		}
2737	}
2738	/* If no lseg, fall back to write through mds */
2739	if (pgio->pg_lseg == NULL)
2740		nfs_pageio_reset_write_mds(pgio);
2741}
2742EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
2743
2744void
2745pnfs_generic_pg_cleanup(struct nfs_pageio_descriptor *desc)
2746{
2747	if (desc->pg_lseg) {
2748		pnfs_put_lseg(desc->pg_lseg);
2749		desc->pg_lseg = NULL;
2750	}
2751}
2752EXPORT_SYMBOL_GPL(pnfs_generic_pg_cleanup);
2753
2754/*
2755 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
2756 * of bytes (maximum @req->wb_bytes) that can be coalesced.
2757 */
2758size_t
2759pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio,
2760		     struct nfs_page *prev, struct nfs_page *req)
2761{
2762	unsigned int size;
2763	u64 seg_end, req_start, seg_left;
2764
2765	size = nfs_generic_pg_test(pgio, prev, req);
2766	if (!size)
2767		return 0;
2768
2769	/*
2770	 * 'size' contains the number of bytes left in the current page (up
2771	 * to the original size asked for in @req->wb_bytes).
2772	 *
2773	 * Calculate how many bytes are left in the layout segment
2774	 * and if there are less bytes than 'size', return that instead.
2775	 *
2776	 * Please also note that 'end_offset' is actually the offset of the
2777	 * first byte that lies outside the pnfs_layout_range. FIXME?
2778	 *
2779	 */
2780	if (pgio->pg_lseg) {
2781		seg_end = pnfs_end_offset(pgio->pg_lseg->pls_range.offset,
2782				     pgio->pg_lseg->pls_range.length);
2783		req_start = req_offset(req);
2784
2785		/* start of request is past the last byte of this segment */
2786		if (req_start >= seg_end)
2787			return 0;
2788
2789		/* adjust 'size' iff there are fewer bytes left in the
2790		 * segment than what nfs_generic_pg_test returned */
2791		seg_left = seg_end - req_start;
2792		if (seg_left < size)
2793			size = (unsigned int)seg_left;
2794	}
2795
2796	return size;
2797}
2798EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
2799
2800int pnfs_write_done_resend_to_mds(struct nfs_pgio_header *hdr)
2801{
2802	struct nfs_pageio_descriptor pgio;
2803
2804	/* Resend all requests through the MDS */
2805	nfs_pageio_init_write(&pgio, hdr->inode, FLUSH_STABLE, true,
2806			      hdr->completion_ops);
2807	set_bit(NFS_CONTEXT_RESEND_WRITES, &hdr->args.context->flags);
2808	return nfs_pageio_resend(&pgio, hdr);
2809}
2810EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
2811
2812static void pnfs_ld_handle_write_error(struct nfs_pgio_header *hdr)
2813{
2814
2815	dprintk("pnfs write error = %d\n", hdr->pnfs_error);
2816	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2817	    PNFS_LAYOUTRET_ON_ERROR) {
2818		pnfs_return_layout(hdr->inode);
2819	}
2820	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2821		hdr->task.tk_status = pnfs_write_done_resend_to_mds(hdr);
2822}
2823
2824/*
2825 * Called by non rpc-based layout drivers
2826 */
2827void pnfs_ld_write_done(struct nfs_pgio_header *hdr)
2828{
2829	if (likely(!hdr->pnfs_error)) {
2830		pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
2831				hdr->mds_offset + hdr->res.count);
2832		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
2833	}
2834	trace_nfs4_pnfs_write(hdr, hdr->pnfs_error);
2835	if (unlikely(hdr->pnfs_error))
2836		pnfs_ld_handle_write_error(hdr);
2837	hdr->mds_ops->rpc_release(hdr);
2838}
2839EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
2840
2841static void
2842pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
2843		struct nfs_pgio_header *hdr)
2844{
2845	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2846
2847	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2848		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
2849		nfs_pageio_reset_write_mds(desc);
2850		mirror->pg_recoalesce = 1;
2851	}
2852	hdr->completion_ops->completion(hdr);
2853}
2854
2855static enum pnfs_try_status
2856pnfs_try_to_write_data(struct nfs_pgio_header *hdr,
2857			const struct rpc_call_ops *call_ops,
2858			struct pnfs_layout_segment *lseg,
2859			int how)
2860{
2861	struct inode *inode = hdr->inode;
2862	enum pnfs_try_status trypnfs;
2863	struct nfs_server *nfss = NFS_SERVER(inode);
2864
2865	hdr->mds_ops = call_ops;
2866
2867	dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
2868		inode->i_ino, hdr->args.count, hdr->args.offset, how);
2869	trypnfs = nfss->pnfs_curr_ld->write_pagelist(hdr, how);
2870	if (trypnfs != PNFS_NOT_ATTEMPTED)
2871		nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
2872	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
2873	return trypnfs;
2874}
2875
2876static void
2877pnfs_do_write(struct nfs_pageio_descriptor *desc,
2878	      struct nfs_pgio_header *hdr, int how)
2879{
2880	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
2881	struct pnfs_layout_segment *lseg = desc->pg_lseg;
2882	enum pnfs_try_status trypnfs;
2883
2884	trypnfs = pnfs_try_to_write_data(hdr, call_ops, lseg, how);
2885	switch (trypnfs) {
2886	case PNFS_NOT_ATTEMPTED:
2887		pnfs_write_through_mds(desc, hdr);
2888		break;
2889	case PNFS_ATTEMPTED:
2890		break;
2891	case PNFS_TRY_AGAIN:
2892		/* cleanup hdr and prepare to redo pnfs */
2893		if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2894			struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2895			list_splice_init(&hdr->pages, &mirror->pg_list);
2896			mirror->pg_recoalesce = 1;
2897		}
2898		hdr->mds_ops->rpc_release(hdr);
2899	}
2900}
2901
2902static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
2903{
2904	pnfs_put_lseg(hdr->lseg);
2905	nfs_pgio_header_free(hdr);
2906}
2907
2908int
2909pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
2910{
2911	struct nfs_pgio_header *hdr;
2912	int ret;
2913
2914	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
2915	if (!hdr) {
2916		desc->pg_error = -ENOMEM;
2917		return desc->pg_error;
2918	}
2919	nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
2920
2921	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
2922	ret = nfs_generic_pgio(desc, hdr);
2923	if (!ret)
2924		pnfs_do_write(desc, hdr, desc->pg_ioflags);
2925
2926	return ret;
2927}
2928EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
2929
2930int pnfs_read_done_resend_to_mds(struct nfs_pgio_header *hdr)
2931{
2932	struct nfs_pageio_descriptor pgio;
2933
2934	/* Resend all requests through the MDS */
2935	nfs_pageio_init_read(&pgio, hdr->inode, true, hdr->completion_ops);
2936	return nfs_pageio_resend(&pgio, hdr);
2937}
2938EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
2939
2940static void pnfs_ld_handle_read_error(struct nfs_pgio_header *hdr)
2941{
2942	dprintk("pnfs read error = %d\n", hdr->pnfs_error);
2943	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2944	    PNFS_LAYOUTRET_ON_ERROR) {
2945		pnfs_return_layout(hdr->inode);
2946	}
2947	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2948		hdr->task.tk_status = pnfs_read_done_resend_to_mds(hdr);
2949}
2950
2951/*
2952 * Called by non rpc-based layout drivers
2953 */
2954void pnfs_ld_read_done(struct nfs_pgio_header *hdr)
2955{
2956	if (likely(!hdr->pnfs_error))
2957		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
2958	trace_nfs4_pnfs_read(hdr, hdr->pnfs_error);
2959	if (unlikely(hdr->pnfs_error))
2960		pnfs_ld_handle_read_error(hdr);
2961	hdr->mds_ops->rpc_release(hdr);
2962}
2963EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
2964
2965static void
2966pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
2967		struct nfs_pgio_header *hdr)
2968{
2969	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2970
2971	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2972		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
2973		nfs_pageio_reset_read_mds(desc);
2974		mirror->pg_recoalesce = 1;
2975	}
2976	hdr->completion_ops->completion(hdr);
2977}
2978
2979/*
2980 * Call the appropriate parallel I/O subsystem read function.
2981 */
2982static enum pnfs_try_status
2983pnfs_try_to_read_data(struct nfs_pgio_header *hdr,
2984		       const struct rpc_call_ops *call_ops,
2985		       struct pnfs_layout_segment *lseg)
2986{
2987	struct inode *inode = hdr->inode;
2988	struct nfs_server *nfss = NFS_SERVER(inode);
2989	enum pnfs_try_status trypnfs;
2990
2991	hdr->mds_ops = call_ops;
2992
2993	dprintk("%s: Reading ino:%lu %u@%llu\n",
2994		__func__, inode->i_ino, hdr->args.count, hdr->args.offset);
2995
2996	trypnfs = nfss->pnfs_curr_ld->read_pagelist(hdr);
2997	if (trypnfs != PNFS_NOT_ATTEMPTED)
2998		nfs_inc_stats(inode, NFSIOS_PNFS_READ);
2999	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
3000	return trypnfs;
3001}
3002
3003/* Resend all requests through pnfs. */
3004void pnfs_read_resend_pnfs(struct nfs_pgio_header *hdr,
3005			   unsigned int mirror_idx)
3006{
3007	struct nfs_pageio_descriptor pgio;
3008
3009	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
3010		/* Prevent deadlocks with layoutreturn! */
3011		pnfs_put_lseg(hdr->lseg);
3012		hdr->lseg = NULL;
3013
3014		nfs_pageio_init_read(&pgio, hdr->inode, false,
3015					hdr->completion_ops);
3016		pgio.pg_mirror_idx = mirror_idx;
3017		hdr->task.tk_status = nfs_pageio_resend(&pgio, hdr);
3018	}
3019}
3020EXPORT_SYMBOL_GPL(pnfs_read_resend_pnfs);
3021
3022static void
3023pnfs_do_read(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr)
3024{
3025	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
3026	struct pnfs_layout_segment *lseg = desc->pg_lseg;
3027	enum pnfs_try_status trypnfs;
3028
3029	trypnfs = pnfs_try_to_read_data(hdr, call_ops, lseg);
3030	switch (trypnfs) {
3031	case PNFS_NOT_ATTEMPTED:
3032		pnfs_read_through_mds(desc, hdr);
3033		break;
3034	case PNFS_ATTEMPTED:
3035		break;
3036	case PNFS_TRY_AGAIN:
3037		/* cleanup hdr and prepare to redo pnfs */
3038		if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
3039			struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
3040			list_splice_init(&hdr->pages, &mirror->pg_list);
3041			mirror->pg_recoalesce = 1;
3042		}
3043		hdr->mds_ops->rpc_release(hdr);
3044	}
3045}
3046
3047static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
3048{
3049	pnfs_put_lseg(hdr->lseg);
3050	nfs_pgio_header_free(hdr);
3051}
3052
3053int
3054pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
3055{
3056	struct nfs_pgio_header *hdr;
3057	int ret;
3058
3059	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
3060	if (!hdr) {
3061		desc->pg_error = -ENOMEM;
3062		return desc->pg_error;
3063	}
3064	nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
3065	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
3066	ret = nfs_generic_pgio(desc, hdr);
3067	if (!ret)
3068		pnfs_do_read(desc, hdr);
3069	return ret;
3070}
3071EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
3072
3073static void pnfs_clear_layoutcommitting(struct inode *inode)
3074{
3075	unsigned long *bitlock = &NFS_I(inode)->flags;
3076
3077	clear_bit_unlock(NFS_INO_LAYOUTCOMMITTING, bitlock);
3078	smp_mb__after_atomic();
3079	wake_up_bit(bitlock, NFS_INO_LAYOUTCOMMITTING);
3080}
3081
3082/*
3083 * There can be multiple RW segments.
3084 */
3085static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
3086{
3087	struct pnfs_layout_segment *lseg;
3088
3089	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
3090		if (lseg->pls_range.iomode == IOMODE_RW &&
3091		    test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
3092			list_add(&lseg->pls_lc_list, listp);
3093	}
3094}
3095
3096static void pnfs_list_write_lseg_done(struct inode *inode, struct list_head *listp)
3097{
3098	struct pnfs_layout_segment *lseg, *tmp;
3099
3100	/* Matched by references in pnfs_set_layoutcommit */
3101	list_for_each_entry_safe(lseg, tmp, listp, pls_lc_list) {
3102		list_del_init(&lseg->pls_lc_list);
3103		pnfs_put_lseg(lseg);
3104	}
3105
3106	pnfs_clear_layoutcommitting(inode);
3107}
3108
3109void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
3110{
3111	pnfs_layout_io_set_failed(lseg->pls_layout, lseg->pls_range.iomode);
3112}
3113EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
3114
3115void
3116pnfs_set_layoutcommit(struct inode *inode, struct pnfs_layout_segment *lseg,
3117		loff_t end_pos)
3118{
3119	struct nfs_inode *nfsi = NFS_I(inode);
3120	bool mark_as_dirty = false;
3121
3122	spin_lock(&inode->i_lock);
3123	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
3124		nfsi->layout->plh_lwb = end_pos;
3125		mark_as_dirty = true;
3126		dprintk("%s: Set layoutcommit for inode %lu ",
3127			__func__, inode->i_ino);
3128	} else if (end_pos > nfsi->layout->plh_lwb)
3129		nfsi->layout->plh_lwb = end_pos;
3130	if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags)) {
3131		/* references matched in nfs4_layoutcommit_release */
3132		pnfs_get_lseg(lseg);
3133	}
3134	spin_unlock(&inode->i_lock);
3135	dprintk("%s: lseg %p end_pos %llu\n",
3136		__func__, lseg, nfsi->layout->plh_lwb);
3137
3138	/* if pnfs_layoutcommit_inode() runs between inode locks, the next one
3139	 * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */
3140	if (mark_as_dirty)
3141		mark_inode_dirty_sync(inode);
3142}
3143EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
3144
3145void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data)
3146{
3147	struct nfs_server *nfss = NFS_SERVER(data->args.inode);
3148
3149	if (nfss->pnfs_curr_ld->cleanup_layoutcommit)
3150		nfss->pnfs_curr_ld->cleanup_layoutcommit(data);
3151	pnfs_list_write_lseg_done(data->args.inode, &data->lseg_list);
3152}
3153
3154/*
3155 * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
3156 * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
3157 * data to disk to allow the server to recover the data if it crashes.
3158 * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
3159 * is off, and a COMMIT is sent to a data server, or
3160 * if WRITEs to a data server return NFS_DATA_SYNC.
3161 */
3162int
3163pnfs_layoutcommit_inode(struct inode *inode, bool sync)
3164{
3165	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
3166	struct nfs4_layoutcommit_data *data;
3167	struct nfs_inode *nfsi = NFS_I(inode);
3168	loff_t end_pos;
3169	int status;
3170
3171	if (!pnfs_layoutcommit_outstanding(inode))
3172		return 0;
3173
3174	dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
3175
3176	status = -EAGAIN;
3177	if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
3178		if (!sync)
3179			goto out;
3180		status = wait_on_bit_lock_action(&nfsi->flags,
3181				NFS_INO_LAYOUTCOMMITTING,
3182				nfs_wait_bit_killable,
3183				TASK_KILLABLE);
3184		if (status)
3185			goto out;
3186	}
3187
3188	status = -ENOMEM;
3189	/* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
3190	data = kzalloc(sizeof(*data), GFP_NOFS);
3191	if (!data)
3192		goto clear_layoutcommitting;
3193
3194	status = 0;
3195	spin_lock(&inode->i_lock);
3196	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
3197		goto out_unlock;
3198
3199	INIT_LIST_HEAD(&data->lseg_list);
3200	pnfs_list_write_lseg(inode, &data->lseg_list);
3201
3202	end_pos = nfsi->layout->plh_lwb;
3203
3204	nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
3205	data->cred = get_cred(nfsi->layout->plh_lc_cred);
3206	spin_unlock(&inode->i_lock);
3207
3208	data->args.inode = inode;
 
3209	nfs_fattr_init(&data->fattr);
3210	data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
3211	data->res.fattr = &data->fattr;
3212	if (end_pos != 0)
3213		data->args.lastbytewritten = end_pos - 1;
3214	else
3215		data->args.lastbytewritten = U64_MAX;
3216	data->res.server = NFS_SERVER(inode);
3217
3218	if (ld->prepare_layoutcommit) {
3219		status = ld->prepare_layoutcommit(&data->args);
3220		if (status) {
3221			put_cred(data->cred);
3222			spin_lock(&inode->i_lock);
3223			set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags);
3224			if (end_pos > nfsi->layout->plh_lwb)
3225				nfsi->layout->plh_lwb = end_pos;
3226			goto out_unlock;
3227		}
3228	}
3229
3230
3231	status = nfs4_proc_layoutcommit(data, sync);
3232out:
3233	if (status)
3234		mark_inode_dirty_sync(inode);
3235	dprintk("<-- %s status %d\n", __func__, status);
3236	return status;
3237out_unlock:
3238	spin_unlock(&inode->i_lock);
3239	kfree(data);
3240clear_layoutcommitting:
3241	pnfs_clear_layoutcommitting(inode);
3242	goto out;
3243}
3244EXPORT_SYMBOL_GPL(pnfs_layoutcommit_inode);
3245
3246int
3247pnfs_generic_sync(struct inode *inode, bool datasync)
3248{
3249	return pnfs_layoutcommit_inode(inode, true);
3250}
3251EXPORT_SYMBOL_GPL(pnfs_generic_sync);
3252
3253struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
3254{
3255	struct nfs4_threshold *thp;
3256
3257	thp = kzalloc(sizeof(*thp), GFP_NOFS);
3258	if (!thp) {
3259		dprintk("%s mdsthreshold allocation failed\n", __func__);
3260		return NULL;
3261	}
3262	return thp;
3263}
3264
3265#if IS_ENABLED(CONFIG_NFS_V4_2)
3266int
3267pnfs_report_layoutstat(struct inode *inode, gfp_t gfp_flags)
3268{
3269	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
3270	struct nfs_server *server = NFS_SERVER(inode);
3271	struct nfs_inode *nfsi = NFS_I(inode);
3272	struct nfs42_layoutstat_data *data;
3273	struct pnfs_layout_hdr *hdr;
3274	int status = 0;
3275
3276	if (!pnfs_enabled_sb(server) || !ld->prepare_layoutstats)
3277		goto out;
3278
3279	if (!nfs_server_capable(inode, NFS_CAP_LAYOUTSTATS))
3280		goto out;
3281
3282	if (test_and_set_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags))
3283		goto out;
3284
3285	spin_lock(&inode->i_lock);
3286	if (!NFS_I(inode)->layout) {
3287		spin_unlock(&inode->i_lock);
3288		goto out_clear_layoutstats;
3289	}
3290	hdr = NFS_I(inode)->layout;
3291	pnfs_get_layout_hdr(hdr);
3292	spin_unlock(&inode->i_lock);
3293
3294	data = kzalloc(sizeof(*data), gfp_flags);
3295	if (!data) {
3296		status = -ENOMEM;
3297		goto out_put;
3298	}
3299
3300	data->args.fh = NFS_FH(inode);
3301	data->args.inode = inode;
3302	status = ld->prepare_layoutstats(&data->args);
3303	if (status)
3304		goto out_free;
3305
3306	status = nfs42_proc_layoutstats_generic(NFS_SERVER(inode), data);
3307
3308out:
3309	dprintk("%s returns %d\n", __func__, status);
3310	return status;
3311
3312out_free:
3313	kfree(data);
3314out_put:
3315	pnfs_put_layout_hdr(hdr);
3316out_clear_layoutstats:
3317	smp_mb__before_atomic();
3318	clear_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags);
3319	smp_mb__after_atomic();
3320	goto out;
3321}
3322EXPORT_SYMBOL_GPL(pnfs_report_layoutstat);
3323#endif
3324
3325unsigned int layoutstats_timer;
3326module_param(layoutstats_timer, uint, 0644);
3327EXPORT_SYMBOL_GPL(layoutstats_timer);
v5.4
   1/*
   2 *  pNFS functions to call and manage layout drivers.
   3 *
   4 *  Copyright (c) 2002 [year of first publication]
   5 *  The Regents of the University of Michigan
   6 *  All Rights Reserved
   7 *
   8 *  Dean Hildebrand <dhildebz@umich.edu>
   9 *
  10 *  Permission is granted to use, copy, create derivative works, and
  11 *  redistribute this software and such derivative works for any purpose,
  12 *  so long as the name of the University of Michigan is not used in
  13 *  any advertising or publicity pertaining to the use or distribution
  14 *  of this software without specific, written prior authorization. If
  15 *  the above copyright notice or any other identification of the
  16 *  University of Michigan is included in any copy of any portion of
  17 *  this software, then the disclaimer below must also be included.
  18 *
  19 *  This software is provided as is, without representation or warranty
  20 *  of any kind either express or implied, including without limitation
  21 *  the implied warranties of merchantability, fitness for a particular
  22 *  purpose, or noninfringement.  The Regents of the University of
  23 *  Michigan shall not be liable for any damages, including special,
  24 *  indirect, incidental, or consequential damages, with respect to any
  25 *  claim arising out of or in connection with the use of the software,
  26 *  even if it has been or is hereafter advised of the possibility of
  27 *  such damages.
  28 */
  29
  30#include <linux/nfs_fs.h>
  31#include <linux/nfs_page.h>
  32#include <linux/module.h>
  33#include <linux/sort.h>
  34#include "internal.h"
  35#include "pnfs.h"
  36#include "iostat.h"
  37#include "nfs4trace.h"
  38#include "delegation.h"
  39#include "nfs42.h"
  40#include "nfs4_fs.h"
  41
  42#define NFSDBG_FACILITY		NFSDBG_PNFS
  43#define PNFS_LAYOUTGET_RETRY_TIMEOUT (120*HZ)
  44
  45/* Locking:
  46 *
  47 * pnfs_spinlock:
  48 *      protects pnfs_modules_tbl.
  49 */
  50static DEFINE_SPINLOCK(pnfs_spinlock);
  51
  52/*
  53 * pnfs_modules_tbl holds all pnfs modules
  54 */
  55static LIST_HEAD(pnfs_modules_tbl);
  56
  57static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo);
  58static void pnfs_free_returned_lsegs(struct pnfs_layout_hdr *lo,
  59		struct list_head *free_me,
  60		const struct pnfs_layout_range *range,
  61		u32 seq);
  62static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
  63		                struct list_head *tmp_list);
  64
  65/* Return the registered pnfs layout driver module matching given id */
  66static struct pnfs_layoutdriver_type *
  67find_pnfs_driver_locked(u32 id)
  68{
  69	struct pnfs_layoutdriver_type *local;
  70
  71	list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid)
  72		if (local->id == id)
  73			goto out;
  74	local = NULL;
  75out:
  76	dprintk("%s: Searching for id %u, found %p\n", __func__, id, local);
  77	return local;
  78}
  79
  80static struct pnfs_layoutdriver_type *
  81find_pnfs_driver(u32 id)
  82{
  83	struct pnfs_layoutdriver_type *local;
  84
  85	spin_lock(&pnfs_spinlock);
  86	local = find_pnfs_driver_locked(id);
  87	if (local != NULL && !try_module_get(local->owner)) {
  88		dprintk("%s: Could not grab reference on module\n", __func__);
  89		local = NULL;
  90	}
  91	spin_unlock(&pnfs_spinlock);
  92	return local;
  93}
  94
  95void
  96unset_pnfs_layoutdriver(struct nfs_server *nfss)
  97{
  98	if (nfss->pnfs_curr_ld) {
  99		if (nfss->pnfs_curr_ld->clear_layoutdriver)
 100			nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
 101		/* Decrement the MDS count. Purge the deviceid cache if zero */
 102		if (atomic_dec_and_test(&nfss->nfs_client->cl_mds_count))
 103			nfs4_deviceid_purge_client(nfss->nfs_client);
 104		module_put(nfss->pnfs_curr_ld->owner);
 105	}
 106	nfss->pnfs_curr_ld = NULL;
 107}
 108
 109/*
 110 * When the server sends a list of layout types, we choose one in the order
 111 * given in the list below.
 112 *
 113 * FIXME: should this list be configurable in some fashion? module param?
 114 * 	  mount option? something else?
 115 */
 116static const u32 ld_prefs[] = {
 117	LAYOUT_SCSI,
 118	LAYOUT_BLOCK_VOLUME,
 119	LAYOUT_OSD2_OBJECTS,
 120	LAYOUT_FLEX_FILES,
 121	LAYOUT_NFSV4_1_FILES,
 122	0
 123};
 124
 125static int
 126ld_cmp(const void *e1, const void *e2)
 127{
 128	u32 ld1 = *((u32 *)e1);
 129	u32 ld2 = *((u32 *)e2);
 130	int i;
 131
 132	for (i = 0; ld_prefs[i] != 0; i++) {
 133		if (ld1 == ld_prefs[i])
 134			return -1;
 135
 136		if (ld2 == ld_prefs[i])
 137			return 1;
 138	}
 139	return 0;
 140}
 141
 142/*
 143 * Try to set the server's pnfs module to the pnfs layout type specified by id.
 144 * Currently only one pNFS layout driver per filesystem is supported.
 145 *
 146 * @ids array of layout types supported by MDS.
 147 */
 148void
 149set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
 150		      struct nfs_fsinfo *fsinfo)
 151{
 152	struct pnfs_layoutdriver_type *ld_type = NULL;
 153	u32 id;
 154	int i;
 155
 156	if (fsinfo->nlayouttypes == 0)
 157		goto out_no_driver;
 158	if (!(server->nfs_client->cl_exchange_flags &
 159		 (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
 160		printk(KERN_ERR "NFS: %s: cl_exchange_flags 0x%x\n",
 161			__func__, server->nfs_client->cl_exchange_flags);
 162		goto out_no_driver;
 163	}
 164
 165	sort(fsinfo->layouttype, fsinfo->nlayouttypes,
 166		sizeof(*fsinfo->layouttype), ld_cmp, NULL);
 167
 168	for (i = 0; i < fsinfo->nlayouttypes; i++) {
 169		id = fsinfo->layouttype[i];
 170		ld_type = find_pnfs_driver(id);
 171		if (!ld_type) {
 172			request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX,
 173					id);
 174			ld_type = find_pnfs_driver(id);
 175		}
 176		if (ld_type)
 177			break;
 178	}
 179
 180	if (!ld_type) {
 181		dprintk("%s: No pNFS module found!\n", __func__);
 182		goto out_no_driver;
 183	}
 184
 185	server->pnfs_curr_ld = ld_type;
 186	if (ld_type->set_layoutdriver
 187	    && ld_type->set_layoutdriver(server, mntfh)) {
 188		printk(KERN_ERR "NFS: %s: Error initializing pNFS layout "
 189			"driver %u.\n", __func__, id);
 190		module_put(ld_type->owner);
 191		goto out_no_driver;
 192	}
 193	/* Bump the MDS count */
 194	atomic_inc(&server->nfs_client->cl_mds_count);
 195
 196	dprintk("%s: pNFS module for %u set\n", __func__, id);
 197	return;
 198
 199out_no_driver:
 200	dprintk("%s: Using NFSv4 I/O\n", __func__);
 201	server->pnfs_curr_ld = NULL;
 202}
 203
 204int
 205pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 206{
 207	int status = -EINVAL;
 208	struct pnfs_layoutdriver_type *tmp;
 209
 210	if (ld_type->id == 0) {
 211		printk(KERN_ERR "NFS: %s id 0 is reserved\n", __func__);
 212		return status;
 213	}
 214	if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
 215		printk(KERN_ERR "NFS: %s Layout driver must provide "
 216		       "alloc_lseg and free_lseg.\n", __func__);
 217		return status;
 218	}
 219
 220	spin_lock(&pnfs_spinlock);
 221	tmp = find_pnfs_driver_locked(ld_type->id);
 222	if (!tmp) {
 223		list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
 224		status = 0;
 225		dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
 226			ld_type->name);
 227	} else {
 228		printk(KERN_ERR "NFS: %s Module with id %d already loaded!\n",
 229			__func__, ld_type->id);
 230	}
 231	spin_unlock(&pnfs_spinlock);
 232
 233	return status;
 234}
 235EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);
 236
 237void
 238pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 239{
 240	dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
 241	spin_lock(&pnfs_spinlock);
 242	list_del(&ld_type->pnfs_tblid);
 243	spin_unlock(&pnfs_spinlock);
 244}
 245EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
 246
 247/*
 248 * pNFS client layout cache
 249 */
 250
 251/* Need to hold i_lock if caller does not already hold reference */
 252void
 253pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo)
 254{
 255	refcount_inc(&lo->plh_refcount);
 256}
 257
 258static struct pnfs_layout_hdr *
 259pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags)
 260{
 261	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
 262	return ld->alloc_layout_hdr(ino, gfp_flags);
 263}
 264
 265static void
 266pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
 267{
 268	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
 269	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
 270
 271	if (!list_empty(&lo->plh_layouts)) {
 272		struct nfs_client *clp = server->nfs_client;
 273
 274		spin_lock(&clp->cl_lock);
 275		list_del_init(&lo->plh_layouts);
 276		spin_unlock(&clp->cl_lock);
 277	}
 278	put_cred(lo->plh_lc_cred);
 279	return ld->free_layout_hdr(lo);
 280}
 281
 282static void
 283pnfs_detach_layout_hdr(struct pnfs_layout_hdr *lo)
 284{
 285	struct nfs_inode *nfsi = NFS_I(lo->plh_inode);
 286	dprintk("%s: freeing layout cache %p\n", __func__, lo);
 287	nfsi->layout = NULL;
 288	/* Reset MDS Threshold I/O counters */
 289	nfsi->write_io = 0;
 290	nfsi->read_io = 0;
 291}
 292
 293void
 294pnfs_put_layout_hdr(struct pnfs_layout_hdr *lo)
 295{
 296	struct inode *inode;
 
 297
 298	if (!lo)
 299		return;
 300	inode = lo->plh_inode;
 301	pnfs_layoutreturn_before_put_layout_hdr(lo);
 302
 303	if (refcount_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
 304		if (!list_empty(&lo->plh_segs))
 305			WARN_ONCE(1, "NFS: BUG unfreed layout segments.\n");
 306		pnfs_detach_layout_hdr(lo);
 
 307		spin_unlock(&inode->i_lock);
 308		pnfs_free_layout_hdr(lo);
 
 
 
 309	}
 310}
 311
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 312static void
 313pnfs_set_plh_return_info(struct pnfs_layout_hdr *lo, enum pnfs_iomode iomode,
 314			 u32 seq)
 315{
 316	if (lo->plh_return_iomode != 0 && lo->plh_return_iomode != iomode)
 317		iomode = IOMODE_ANY;
 318	lo->plh_return_iomode = iomode;
 319	set_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 320	if (seq != 0) {
 321		WARN_ON_ONCE(lo->plh_return_seq != 0 && lo->plh_return_seq != seq);
 
 
 
 
 
 322		lo->plh_return_seq = seq;
 323	}
 324}
 325
 326static void
 327pnfs_clear_layoutreturn_info(struct pnfs_layout_hdr *lo)
 328{
 329	struct pnfs_layout_segment *lseg;
 330	lo->plh_return_iomode = 0;
 331	lo->plh_return_seq = 0;
 332	clear_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 333	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
 334		if (!test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
 335			continue;
 336		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
 337	}
 338}
 339
 340static void pnfs_clear_layoutreturn_waitbit(struct pnfs_layout_hdr *lo)
 341{
 342	clear_bit_unlock(NFS_LAYOUT_RETURN, &lo->plh_flags);
 343	clear_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags);
 344	smp_mb__after_atomic();
 345	wake_up_bit(&lo->plh_flags, NFS_LAYOUT_RETURN);
 346	rpc_wake_up(&NFS_SERVER(lo->plh_inode)->roc_rpcwaitq);
 347}
 348
 349static void
 350pnfs_clear_lseg_state(struct pnfs_layout_segment *lseg,
 351		struct list_head *free_me)
 352{
 353	clear_bit(NFS_LSEG_ROC, &lseg->pls_flags);
 354	clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
 355	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags))
 356		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 357	if (test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
 358		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 359}
 360
 361/*
 362 * Update the seqid of a layout stateid after receiving
 363 * NFS4ERR_OLD_STATEID
 364 */
 365bool nfs4_layout_refresh_old_stateid(nfs4_stateid *dst,
 366		struct pnfs_layout_range *dst_range,
 367		struct inode *inode)
 368{
 369	struct pnfs_layout_hdr *lo;
 370	struct pnfs_layout_range range = {
 371		.iomode = IOMODE_ANY,
 372		.offset = 0,
 373		.length = NFS4_MAX_UINT64,
 374	};
 375	bool ret = false;
 376	LIST_HEAD(head);
 377	int err;
 378
 379	spin_lock(&inode->i_lock);
 380	lo = NFS_I(inode)->layout;
 381	if (lo &&  pnfs_layout_is_valid(lo) &&
 382	    nfs4_stateid_match_other(dst, &lo->plh_stateid)) {
 383		/* Is our call using the most recent seqid? If so, bump it */
 384		if (!nfs4_stateid_is_newer(&lo->plh_stateid, dst)) {
 385			nfs4_stateid_seqid_inc(dst);
 386			ret = true;
 387			goto out;
 388		}
 389		/* Try to update the seqid to the most recent */
 390		err = pnfs_mark_matching_lsegs_return(lo, &head, &range, 0);
 391		if (err != -EBUSY) {
 392			dst->seqid = lo->plh_stateid.seqid;
 393			*dst_range = range;
 394			ret = true;
 395		}
 396	}
 397out:
 398	spin_unlock(&inode->i_lock);
 399	pnfs_free_lseg_list(&head);
 400	return ret;
 401}
 402
 403/*
 404 * Mark a pnfs_layout_hdr and all associated layout segments as invalid
 405 *
 406 * In order to continue using the pnfs_layout_hdr, a full recovery
 407 * is required.
 408 * Note that caller must hold inode->i_lock.
 409 */
 410int
 411pnfs_mark_layout_stateid_invalid(struct pnfs_layout_hdr *lo,
 412		struct list_head *lseg_list)
 413{
 414	struct pnfs_layout_range range = {
 415		.iomode = IOMODE_ANY,
 416		.offset = 0,
 417		.length = NFS4_MAX_UINT64,
 418	};
 419	struct pnfs_layout_segment *lseg, *next;
 420
 421	set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 422	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 423		pnfs_clear_lseg_state(lseg, lseg_list);
 424	pnfs_clear_layoutreturn_info(lo);
 425	pnfs_free_returned_lsegs(lo, lseg_list, &range, 0);
 426	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags) &&
 427	    !test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
 428		pnfs_clear_layoutreturn_waitbit(lo);
 429	return !list_empty(&lo->plh_segs);
 430}
 431
 432static int
 433pnfs_iomode_to_fail_bit(u32 iomode)
 434{
 435	return iomode == IOMODE_RW ?
 436		NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 437}
 438
 439static void
 440pnfs_layout_set_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 441{
 442	lo->plh_retry_timestamp = jiffies;
 443	if (!test_and_set_bit(fail_bit, &lo->plh_flags))
 444		refcount_inc(&lo->plh_refcount);
 445}
 446
 447static void
 448pnfs_layout_clear_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 449{
 450	if (test_and_clear_bit(fail_bit, &lo->plh_flags))
 451		refcount_dec(&lo->plh_refcount);
 452}
 453
 454static void
 455pnfs_layout_io_set_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 456{
 457	struct inode *inode = lo->plh_inode;
 458	struct pnfs_layout_range range = {
 459		.iomode = iomode,
 460		.offset = 0,
 461		.length = NFS4_MAX_UINT64,
 462	};
 463	LIST_HEAD(head);
 464
 465	spin_lock(&inode->i_lock);
 466	pnfs_layout_set_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
 467	pnfs_mark_matching_lsegs_invalid(lo, &head, &range, 0);
 468	spin_unlock(&inode->i_lock);
 469	pnfs_free_lseg_list(&head);
 470	dprintk("%s Setting layout IOMODE_%s fail bit\n", __func__,
 471			iomode == IOMODE_RW ?  "RW" : "READ");
 472}
 473
 474static bool
 475pnfs_layout_io_test_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 476{
 477	unsigned long start, end;
 478	int fail_bit = pnfs_iomode_to_fail_bit(iomode);
 479
 480	if (test_bit(fail_bit, &lo->plh_flags) == 0)
 481		return false;
 482	end = jiffies;
 483	start = end - PNFS_LAYOUTGET_RETRY_TIMEOUT;
 484	if (!time_in_range(lo->plh_retry_timestamp, start, end)) {
 485		/* It is time to retry the failed layoutgets */
 486		pnfs_layout_clear_fail_bit(lo, fail_bit);
 487		return false;
 488	}
 489	return true;
 490}
 491
 492static void
 493pnfs_init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg,
 494		const struct pnfs_layout_range *range,
 495		const nfs4_stateid *stateid)
 496{
 497	INIT_LIST_HEAD(&lseg->pls_list);
 498	INIT_LIST_HEAD(&lseg->pls_lc_list);
 
 499	refcount_set(&lseg->pls_refcount, 1);
 500	set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
 501	lseg->pls_layout = lo;
 502	lseg->pls_range = *range;
 503	lseg->pls_seq = be32_to_cpu(stateid->seqid);
 504}
 505
 506static void pnfs_free_lseg(struct pnfs_layout_segment *lseg)
 507{
 508	if (lseg != NULL) {
 509		struct inode *inode = lseg->pls_layout->plh_inode;
 510		NFS_SERVER(inode)->pnfs_curr_ld->free_lseg(lseg);
 511	}
 512}
 513
 514static void
 515pnfs_layout_remove_lseg(struct pnfs_layout_hdr *lo,
 516		struct pnfs_layout_segment *lseg)
 517{
 518	WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 519	list_del_init(&lseg->pls_list);
 520	/* Matched by pnfs_get_layout_hdr in pnfs_layout_insert_lseg */
 521	refcount_dec(&lo->plh_refcount);
 522	if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
 523		return;
 524	if (list_empty(&lo->plh_segs) &&
 525	    !test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) &&
 526	    !test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
 527		if (atomic_read(&lo->plh_outstanding) == 0)
 528			set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 529		clear_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 530	}
 531}
 532
 533static bool
 534pnfs_cache_lseg_for_layoutreturn(struct pnfs_layout_hdr *lo,
 535		struct pnfs_layout_segment *lseg)
 536{
 537	if (test_and_clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags) &&
 538	    pnfs_layout_is_valid(lo)) {
 539		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
 540		list_move_tail(&lseg->pls_list, &lo->plh_return_segs);
 541		return true;
 542	}
 543	return false;
 544}
 545
 546void
 547pnfs_put_lseg(struct pnfs_layout_segment *lseg)
 548{
 549	struct pnfs_layout_hdr *lo;
 550	struct inode *inode;
 551
 552	if (!lseg)
 553		return;
 554
 555	dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
 556		refcount_read(&lseg->pls_refcount),
 557		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 558
 559	lo = lseg->pls_layout;
 560	inode = lo->plh_inode;
 561
 562	if (refcount_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
 563		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 564			spin_unlock(&inode->i_lock);
 565			return;
 566		}
 567		pnfs_get_layout_hdr(lo);
 568		pnfs_layout_remove_lseg(lo, lseg);
 569		if (pnfs_cache_lseg_for_layoutreturn(lo, lseg))
 570			lseg = NULL;
 571		spin_unlock(&inode->i_lock);
 572		pnfs_free_lseg(lseg);
 573		pnfs_put_layout_hdr(lo);
 574	}
 575}
 576EXPORT_SYMBOL_GPL(pnfs_put_lseg);
 577
 578/*
 579 * is l2 fully contained in l1?
 580 *   start1                             end1
 581 *   [----------------------------------)
 582 *           start2           end2
 583 *           [----------------)
 584 */
 585static bool
 586pnfs_lseg_range_contained(const struct pnfs_layout_range *l1,
 587		 const struct pnfs_layout_range *l2)
 588{
 589	u64 start1 = l1->offset;
 590	u64 end1 = pnfs_end_offset(start1, l1->length);
 591	u64 start2 = l2->offset;
 592	u64 end2 = pnfs_end_offset(start2, l2->length);
 593
 594	return (start1 <= start2) && (end1 >= end2);
 595}
 596
 597static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
 598		struct list_head *tmp_list)
 599{
 600	if (!refcount_dec_and_test(&lseg->pls_refcount))
 601		return false;
 602	pnfs_layout_remove_lseg(lseg->pls_layout, lseg);
 603	list_add(&lseg->pls_list, tmp_list);
 604	return true;
 605}
 606
 607/* Returns 1 if lseg is removed from list, 0 otherwise */
 608static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
 609			     struct list_head *tmp_list)
 610{
 611	int rv = 0;
 612
 613	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 614		/* Remove the reference keeping the lseg in the
 615		 * list.  It will now be removed when all
 616		 * outstanding io is finished.
 617		 */
 618		dprintk("%s: lseg %p ref %d\n", __func__, lseg,
 619			refcount_read(&lseg->pls_refcount));
 620		if (pnfs_lseg_dec_and_remove_zero(lseg, tmp_list))
 621			rv = 1;
 622	}
 623	return rv;
 624}
 625
 626/*
 627 * Compare 2 layout stateid sequence ids, to see which is newer,
 628 * taking into account wraparound issues.
 629 */
 630static bool pnfs_seqid_is_newer(u32 s1, u32 s2)
 631{
 632	return (s32)(s1 - s2) > 0;
 633}
 634
 635static bool
 636pnfs_should_free_range(const struct pnfs_layout_range *lseg_range,
 637		 const struct pnfs_layout_range *recall_range)
 638{
 639	return (recall_range->iomode == IOMODE_ANY ||
 640		lseg_range->iomode == recall_range->iomode) &&
 641	       pnfs_lseg_range_intersecting(lseg_range, recall_range);
 642}
 643
 644static bool
 645pnfs_match_lseg_recall(const struct pnfs_layout_segment *lseg,
 646		const struct pnfs_layout_range *recall_range,
 647		u32 seq)
 648{
 649	if (seq != 0 && pnfs_seqid_is_newer(lseg->pls_seq, seq))
 650		return false;
 651	if (recall_range == NULL)
 652		return true;
 653	return pnfs_should_free_range(&lseg->pls_range, recall_range);
 654}
 655
 656/**
 657 * pnfs_mark_matching_lsegs_invalid - tear down lsegs or mark them for later
 658 * @lo: layout header containing the lsegs
 659 * @tmp_list: list head where doomed lsegs should go
 660 * @recall_range: optional recall range argument to match (may be NULL)
 661 * @seq: only invalidate lsegs obtained prior to this sequence (may be 0)
 662 *
 663 * Walk the list of lsegs in the layout header, and tear down any that should
 664 * be destroyed. If "recall_range" is specified then the segment must match
 665 * that range. If "seq" is non-zero, then only match segments that were handed
 666 * out at or before that sequence.
 667 *
 668 * Returns number of matching invalid lsegs remaining in list after scanning
 669 * it and purging them.
 670 */
 671int
 672pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 673			    struct list_head *tmp_list,
 674			    const struct pnfs_layout_range *recall_range,
 675			    u32 seq)
 676{
 677	struct pnfs_layout_segment *lseg, *next;
 678	int remaining = 0;
 679
 680	dprintk("%s:Begin lo %p\n", __func__, lo);
 681
 682	if (list_empty(&lo->plh_segs))
 683		return 0;
 684	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 685		if (pnfs_match_lseg_recall(lseg, recall_range, seq)) {
 686			dprintk("%s: freeing lseg %p iomode %d seq %u "
 687				"offset %llu length %llu\n", __func__,
 688				lseg, lseg->pls_range.iomode, lseg->pls_seq,
 689				lseg->pls_range.offset, lseg->pls_range.length);
 690			if (!mark_lseg_invalid(lseg, tmp_list))
 691				remaining++;
 692		}
 693	dprintk("%s:Return %i\n", __func__, remaining);
 694	return remaining;
 695}
 696
 697static void
 698pnfs_free_returned_lsegs(struct pnfs_layout_hdr *lo,
 699		struct list_head *free_me,
 700		const struct pnfs_layout_range *range,
 701		u32 seq)
 702{
 703	struct pnfs_layout_segment *lseg, *next;
 704
 705	list_for_each_entry_safe(lseg, next, &lo->plh_return_segs, pls_list) {
 706		if (pnfs_match_lseg_recall(lseg, range, seq))
 707			list_move_tail(&lseg->pls_list, free_me);
 708	}
 709}
 710
 711/* note free_me must contain lsegs from a single layout_hdr */
 712void
 713pnfs_free_lseg_list(struct list_head *free_me)
 714{
 715	struct pnfs_layout_segment *lseg, *tmp;
 716
 717	if (list_empty(free_me))
 718		return;
 719
 720	list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
 721		list_del(&lseg->pls_list);
 722		pnfs_free_lseg(lseg);
 723	}
 724}
 725
 726void
 727pnfs_destroy_layout(struct nfs_inode *nfsi)
 728{
 729	struct pnfs_layout_hdr *lo;
 730	LIST_HEAD(tmp_list);
 731
 732	spin_lock(&nfsi->vfs_inode.i_lock);
 733	lo = nfsi->layout;
 734	if (lo) {
 735		pnfs_get_layout_hdr(lo);
 736		pnfs_mark_layout_stateid_invalid(lo, &tmp_list);
 737		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RO_FAILED);
 738		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RW_FAILED);
 739		spin_unlock(&nfsi->vfs_inode.i_lock);
 740		pnfs_free_lseg_list(&tmp_list);
 741		nfs_commit_inode(&nfsi->vfs_inode, 0);
 742		pnfs_put_layout_hdr(lo);
 743	} else
 744		spin_unlock(&nfsi->vfs_inode.i_lock);
 
 
 
 
 
 
 745}
 746EXPORT_SYMBOL_GPL(pnfs_destroy_layout);
 747
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 748static bool
 749pnfs_layout_add_bulk_destroy_list(struct inode *inode,
 750		struct list_head *layout_list)
 751{
 752	struct pnfs_layout_hdr *lo;
 753	bool ret = false;
 754
 755	spin_lock(&inode->i_lock);
 756	lo = NFS_I(inode)->layout;
 757	if (lo != NULL && list_empty(&lo->plh_bulk_destroy)) {
 758		pnfs_get_layout_hdr(lo);
 759		list_add(&lo->plh_bulk_destroy, layout_list);
 760		ret = true;
 761	}
 762	spin_unlock(&inode->i_lock);
 763	return ret;
 764}
 765
 766/* Caller must hold rcu_read_lock and clp->cl_lock */
 767static int
 768pnfs_layout_bulk_destroy_byserver_locked(struct nfs_client *clp,
 769		struct nfs_server *server,
 770		struct list_head *layout_list)
 771	__must_hold(&clp->cl_lock)
 772	__must_hold(RCU)
 773{
 774	struct pnfs_layout_hdr *lo, *next;
 775	struct inode *inode;
 776
 777	list_for_each_entry_safe(lo, next, &server->layouts, plh_layouts) {
 778		if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags) ||
 779		    test_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags) ||
 780		    !list_empty(&lo->plh_bulk_destroy))
 781			continue;
 782		/* If the sb is being destroyed, just bail */
 783		if (!nfs_sb_active(server->super))
 784			break;
 785		inode = igrab(lo->plh_inode);
 786		if (inode != NULL) {
 787			list_del_init(&lo->plh_layouts);
 
 788			if (pnfs_layout_add_bulk_destroy_list(inode,
 789						layout_list))
 790				continue;
 791			rcu_read_unlock();
 792			spin_unlock(&clp->cl_lock);
 793			iput(inode);
 794		} else {
 795			rcu_read_unlock();
 796			spin_unlock(&clp->cl_lock);
 797			set_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags);
 798		}
 799		nfs_sb_deactive(server->super);
 800		spin_lock(&clp->cl_lock);
 801		rcu_read_lock();
 802		return -EAGAIN;
 803	}
 804	return 0;
 805}
 806
 807static int
 808pnfs_layout_free_bulk_destroy_list(struct list_head *layout_list,
 809		bool is_bulk_recall)
 810{
 811	struct pnfs_layout_hdr *lo;
 812	struct inode *inode;
 813	LIST_HEAD(lseg_list);
 814	int ret = 0;
 815
 816	while (!list_empty(layout_list)) {
 817		lo = list_entry(layout_list->next, struct pnfs_layout_hdr,
 818				plh_bulk_destroy);
 819		dprintk("%s freeing layout for inode %lu\n", __func__,
 820			lo->plh_inode->i_ino);
 821		inode = lo->plh_inode;
 822
 823		pnfs_layoutcommit_inode(inode, false);
 824
 825		spin_lock(&inode->i_lock);
 826		list_del_init(&lo->plh_bulk_destroy);
 827		if (pnfs_mark_layout_stateid_invalid(lo, &lseg_list)) {
 828			if (is_bulk_recall)
 829				set_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 830			ret = -EAGAIN;
 831		}
 832		spin_unlock(&inode->i_lock);
 833		pnfs_free_lseg_list(&lseg_list);
 834		/* Free all lsegs that are attached to commit buckets */
 835		nfs_commit_inode(inode, 0);
 836		pnfs_put_layout_hdr(lo);
 837		nfs_iput_and_deactive(inode);
 838	}
 839	return ret;
 840}
 841
 842int
 843pnfs_destroy_layouts_byfsid(struct nfs_client *clp,
 844		struct nfs_fsid *fsid,
 845		bool is_recall)
 846{
 847	struct nfs_server *server;
 848	LIST_HEAD(layout_list);
 849
 850	spin_lock(&clp->cl_lock);
 851	rcu_read_lock();
 852restart:
 853	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 854		if (memcmp(&server->fsid, fsid, sizeof(*fsid)) != 0)
 855			continue;
 856		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 857				server,
 858				&layout_list) != 0)
 859			goto restart;
 860	}
 861	rcu_read_unlock();
 862	spin_unlock(&clp->cl_lock);
 863
 864	if (list_empty(&layout_list))
 865		return 0;
 866	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 867}
 868
 869int
 870pnfs_destroy_layouts_byclid(struct nfs_client *clp,
 871		bool is_recall)
 872{
 873	struct nfs_server *server;
 874	LIST_HEAD(layout_list);
 875
 876	spin_lock(&clp->cl_lock);
 877	rcu_read_lock();
 878restart:
 879	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 880		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 881					server,
 882					&layout_list) != 0)
 883			goto restart;
 884	}
 885	rcu_read_unlock();
 886	spin_unlock(&clp->cl_lock);
 887
 888	if (list_empty(&layout_list))
 889		return 0;
 890	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 891}
 892
 893/*
 894 * Called by the state manger to remove all layouts established under an
 895 * expired lease.
 896 */
 897void
 898pnfs_destroy_all_layouts(struct nfs_client *clp)
 899{
 900	nfs4_deviceid_mark_client_invalid(clp);
 901	nfs4_deviceid_purge_client(clp);
 902
 903	pnfs_destroy_layouts_byclid(clp, false);
 904}
 905
 
 
 
 
 
 
 
 
 
 
 
 906/* update lo->plh_stateid with new if is more recent */
 907void
 908pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
 909			bool update_barrier)
 910{
 911	u32 oldseq, newseq, new_barrier = 0;
 912
 913	oldseq = be32_to_cpu(lo->plh_stateid.seqid);
 914	newseq = be32_to_cpu(new->seqid);
 915
 916	if (!pnfs_layout_is_valid(lo)) {
 
 917		nfs4_stateid_copy(&lo->plh_stateid, new);
 918		lo->plh_barrier = newseq;
 919		pnfs_clear_layoutreturn_info(lo);
 920		clear_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 921		return;
 922	}
 923	if (pnfs_seqid_is_newer(newseq, oldseq)) {
 
 924		nfs4_stateid_copy(&lo->plh_stateid, new);
 925		/*
 926		 * Because of wraparound, we want to keep the barrier
 927		 * "close" to the current seqids.
 928		 */
 929		new_barrier = newseq - atomic_read(&lo->plh_outstanding);
 930	}
 931	if (update_barrier)
 932		new_barrier = be32_to_cpu(new->seqid);
 933	else if (new_barrier == 0)
 934		return;
 935	if (pnfs_seqid_is_newer(new_barrier, lo->plh_barrier))
 936		lo->plh_barrier = new_barrier;
 
 937}
 938
 939static bool
 940pnfs_layout_stateid_blocked(const struct pnfs_layout_hdr *lo,
 941		const nfs4_stateid *stateid)
 942{
 943	u32 seqid = be32_to_cpu(stateid->seqid);
 944
 945	return !pnfs_seqid_is_newer(seqid, lo->plh_barrier);
 946}
 947
 948/* lget is set to 1 if called from inside send_layoutget call chain */
 949static bool
 950pnfs_layoutgets_blocked(const struct pnfs_layout_hdr *lo)
 951{
 952	return lo->plh_block_lgets ||
 953		test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 954}
 955
 956static struct nfs_server *
 957pnfs_find_server(struct inode *inode, struct nfs_open_context *ctx)
 958{
 959	struct nfs_server *server;
 960
 961	if (inode) {
 962		server = NFS_SERVER(inode);
 963	} else {
 964		struct dentry *parent_dir = dget_parent(ctx->dentry);
 965		server = NFS_SERVER(parent_dir->d_inode);
 966		dput(parent_dir);
 967	}
 968	return server;
 969}
 970
 971static void nfs4_free_pages(struct page **pages, size_t size)
 972{
 973	int i;
 974
 975	if (!pages)
 976		return;
 977
 978	for (i = 0; i < size; i++) {
 979		if (!pages[i])
 980			break;
 981		__free_page(pages[i]);
 982	}
 983	kfree(pages);
 984}
 985
 986static struct page **nfs4_alloc_pages(size_t size, gfp_t gfp_flags)
 987{
 988	struct page **pages;
 989	int i;
 990
 991	pages = kmalloc_array(size, sizeof(struct page *), gfp_flags);
 992	if (!pages) {
 993		dprintk("%s: can't alloc array of %zu pages\n", __func__, size);
 994		return NULL;
 995	}
 996
 997	for (i = 0; i < size; i++) {
 998		pages[i] = alloc_page(gfp_flags);
 999		if (!pages[i]) {
1000			dprintk("%s: failed to allocate page\n", __func__);
1001			nfs4_free_pages(pages, i);
1002			return NULL;
1003		}
1004	}
1005
1006	return pages;
1007}
1008
1009static struct nfs4_layoutget *
1010pnfs_alloc_init_layoutget_args(struct inode *ino,
1011	   struct nfs_open_context *ctx,
1012	   const nfs4_stateid *stateid,
1013	   const struct pnfs_layout_range *range,
1014	   gfp_t gfp_flags)
1015{
1016	struct nfs_server *server = pnfs_find_server(ino, ctx);
1017	size_t max_reply_sz = server->pnfs_curr_ld->max_layoutget_response;
1018	size_t max_pages = max_response_pages(server);
1019	struct nfs4_layoutget *lgp;
1020
1021	dprintk("--> %s\n", __func__);
1022
1023	lgp = kzalloc(sizeof(*lgp), gfp_flags);
1024	if (lgp == NULL)
1025		return NULL;
1026
1027	if (max_reply_sz) {
1028		size_t npages = (max_reply_sz + PAGE_SIZE - 1) >> PAGE_SHIFT;
1029		if (npages < max_pages)
1030			max_pages = npages;
1031	}
1032
1033	lgp->args.layout.pages = nfs4_alloc_pages(max_pages, gfp_flags);
1034	if (!lgp->args.layout.pages) {
1035		kfree(lgp);
1036		return NULL;
1037	}
1038	lgp->args.layout.pglen = max_pages * PAGE_SIZE;
1039	lgp->res.layoutp = &lgp->args.layout;
1040
1041	/* Don't confuse uninitialised result and success */
1042	lgp->res.status = -NFS4ERR_DELAY;
1043
1044	lgp->args.minlength = PAGE_SIZE;
1045	if (lgp->args.minlength > range->length)
1046		lgp->args.minlength = range->length;
1047	if (ino) {
1048		loff_t i_size = i_size_read(ino);
1049
1050		if (range->iomode == IOMODE_READ) {
1051			if (range->offset >= i_size)
1052				lgp->args.minlength = 0;
1053			else if (i_size - range->offset < lgp->args.minlength)
1054				lgp->args.minlength = i_size - range->offset;
1055		}
1056	}
1057	lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
1058	pnfs_copy_range(&lgp->args.range, range);
1059	lgp->args.type = server->pnfs_curr_ld->id;
1060	lgp->args.inode = ino;
1061	lgp->args.ctx = get_nfs_open_context(ctx);
1062	nfs4_stateid_copy(&lgp->args.stateid, stateid);
1063	lgp->gfp_flags = gfp_flags;
1064	lgp->cred = get_cred(ctx->cred);
1065	return lgp;
1066}
1067
1068void pnfs_layoutget_free(struct nfs4_layoutget *lgp)
1069{
1070	size_t max_pages = lgp->args.layout.pglen / PAGE_SIZE;
1071
1072	nfs4_free_pages(lgp->args.layout.pages, max_pages);
1073	if (lgp->args.inode)
1074		pnfs_put_layout_hdr(NFS_I(lgp->args.inode)->layout);
1075	put_cred(lgp->cred);
1076	put_nfs_open_context(lgp->args.ctx);
1077	kfree(lgp);
1078}
1079
1080static void pnfs_clear_layoutcommit(struct inode *inode,
1081		struct list_head *head)
1082{
1083	struct nfs_inode *nfsi = NFS_I(inode);
1084	struct pnfs_layout_segment *lseg, *tmp;
1085
1086	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
1087		return;
1088	list_for_each_entry_safe(lseg, tmp, &nfsi->layout->plh_segs, pls_list) {
1089		if (!test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
1090			continue;
1091		pnfs_lseg_dec_and_remove_zero(lseg, head);
1092	}
1093}
1094
1095void pnfs_layoutreturn_free_lsegs(struct pnfs_layout_hdr *lo,
1096		const nfs4_stateid *arg_stateid,
1097		const struct pnfs_layout_range *range,
1098		const nfs4_stateid *stateid)
1099{
1100	struct inode *inode = lo->plh_inode;
1101	LIST_HEAD(freeme);
1102
1103	spin_lock(&inode->i_lock);
1104	if (!pnfs_layout_is_valid(lo) || !arg_stateid ||
1105	    !nfs4_stateid_match_other(&lo->plh_stateid, arg_stateid))
1106		goto out_unlock;
1107	if (stateid) {
1108		u32 seq = be32_to_cpu(arg_stateid->seqid);
1109
1110		pnfs_mark_matching_lsegs_invalid(lo, &freeme, range, seq);
1111		pnfs_free_returned_lsegs(lo, &freeme, range, seq);
1112		pnfs_set_layout_stateid(lo, stateid, true);
1113	} else
1114		pnfs_mark_layout_stateid_invalid(lo, &freeme);
1115out_unlock:
1116	pnfs_clear_layoutreturn_waitbit(lo);
1117	spin_unlock(&inode->i_lock);
1118	pnfs_free_lseg_list(&freeme);
1119
1120}
1121
1122static bool
1123pnfs_prepare_layoutreturn(struct pnfs_layout_hdr *lo,
1124		nfs4_stateid *stateid,
 
1125		enum pnfs_iomode *iomode)
1126{
1127	/* Serialise LAYOUTGET/LAYOUTRETURN */
1128	if (atomic_read(&lo->plh_outstanding) != 0)
1129		return false;
1130	if (test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
1131		return false;
1132	set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
1133	pnfs_get_layout_hdr(lo);
 
 
1134	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags)) {
1135		if (stateid != NULL) {
1136			nfs4_stateid_copy(stateid, &lo->plh_stateid);
1137			if (lo->plh_return_seq != 0)
1138				stateid->seqid = cpu_to_be32(lo->plh_return_seq);
1139		}
1140		if (iomode != NULL)
1141			*iomode = lo->plh_return_iomode;
1142		pnfs_clear_layoutreturn_info(lo);
1143		return true;
1144	}
1145	if (stateid != NULL)
1146		nfs4_stateid_copy(stateid, &lo->plh_stateid);
1147	if (iomode != NULL)
1148		*iomode = IOMODE_ANY;
 
1149	return true;
1150}
1151
1152static void
1153pnfs_init_layoutreturn_args(struct nfs4_layoutreturn_args *args,
1154		struct pnfs_layout_hdr *lo,
1155		const nfs4_stateid *stateid,
1156		enum pnfs_iomode iomode)
1157{
1158	struct inode *inode = lo->plh_inode;
1159
1160	args->layout_type = NFS_SERVER(inode)->pnfs_curr_ld->id;
1161	args->inode = inode;
1162	args->range.iomode = iomode;
1163	args->range.offset = 0;
1164	args->range.length = NFS4_MAX_UINT64;
1165	args->layout = lo;
1166	nfs4_stateid_copy(&args->stateid, stateid);
1167}
1168
1169static int
1170pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo, const nfs4_stateid *stateid,
1171		       enum pnfs_iomode iomode, bool sync)
 
 
 
1172{
1173	struct inode *ino = lo->plh_inode;
1174	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1175	struct nfs4_layoutreturn *lrp;
 
1176	int status = 0;
1177
 
1178	lrp = kzalloc(sizeof(*lrp), GFP_NOFS);
1179	if (unlikely(lrp == NULL)) {
1180		status = -ENOMEM;
1181		spin_lock(&ino->i_lock);
1182		pnfs_clear_layoutreturn_waitbit(lo);
1183		spin_unlock(&ino->i_lock);
 
1184		pnfs_put_layout_hdr(lo);
1185		goto out;
1186	}
1187
1188	pnfs_init_layoutreturn_args(&lrp->args, lo, stateid, iomode);
1189	lrp->args.ld_private = &lrp->ld_private;
1190	lrp->clp = NFS_SERVER(ino)->nfs_client;
1191	lrp->cred = lo->plh_lc_cred;
1192	if (ld->prepare_layoutreturn)
1193		ld->prepare_layoutreturn(&lrp->args);
1194
1195	status = nfs4_proc_layoutreturn(lrp, sync);
1196out:
1197	dprintk("<-- %s status: %d\n", __func__, status);
1198	return status;
1199}
1200
 
 
 
 
 
 
 
 
 
 
 
 
 
1201/* Return true if layoutreturn is needed */
1202static bool
1203pnfs_layout_need_return(struct pnfs_layout_hdr *lo)
1204{
1205	struct pnfs_layout_segment *s;
1206	enum pnfs_iomode iomode;
1207	u32 seq;
1208
1209	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1210		return false;
1211
1212	seq = lo->plh_return_seq;
1213	iomode = lo->plh_return_iomode;
1214
1215	/* Defer layoutreturn until all recalled lsegs are done */
1216	list_for_each_entry(s, &lo->plh_segs, pls_list) {
1217		if (seq && pnfs_seqid_is_newer(s->pls_seq, seq))
1218			continue;
1219		if (iomode != IOMODE_ANY && s->pls_range.iomode != iomode)
1220			continue;
1221		if (test_bit(NFS_LSEG_LAYOUTRETURN, &s->pls_flags))
1222			return false;
1223	}
1224
1225	return true;
1226}
1227
1228static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo)
1229{
1230	struct inode *inode= lo->plh_inode;
1231
1232	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1233		return;
1234	spin_lock(&inode->i_lock);
1235	if (pnfs_layout_need_return(lo)) {
 
1236		nfs4_stateid stateid;
1237		enum pnfs_iomode iomode;
1238		bool send;
1239
1240		send = pnfs_prepare_layoutreturn(lo, &stateid, &iomode);
1241		spin_unlock(&inode->i_lock);
1242		if (send) {
1243			/* Send an async layoutreturn so we dont deadlock */
1244			pnfs_send_layoutreturn(lo, &stateid, iomode, false);
1245		}
1246	} else
1247		spin_unlock(&inode->i_lock);
1248}
1249
1250/*
1251 * Initiates a LAYOUTRETURN(FILE), and removes the pnfs_layout_hdr
1252 * when the layout segment list is empty.
1253 *
1254 * Note that a pnfs_layout_hdr can exist with an empty layout segment
1255 * list when LAYOUTGET has failed, or when LAYOUTGET succeeded, but the
1256 * deviceid is marked invalid.
1257 */
1258int
1259_pnfs_return_layout(struct inode *ino)
1260{
1261	struct pnfs_layout_hdr *lo = NULL;
1262	struct nfs_inode *nfsi = NFS_I(ino);
 
 
 
 
 
1263	LIST_HEAD(tmp_list);
 
1264	nfs4_stateid stateid;
1265	int status = 0;
1266	bool send, valid_layout;
1267
1268	dprintk("NFS: %s for inode %lu\n", __func__, ino->i_ino);
1269
1270	spin_lock(&ino->i_lock);
1271	lo = nfsi->layout;
1272	if (!lo) {
1273		spin_unlock(&ino->i_lock);
1274		dprintk("NFS: %s no layout to return\n", __func__);
1275		goto out;
1276	}
1277	/* Reference matched in nfs4_layoutreturn_release */
1278	pnfs_get_layout_hdr(lo);
1279	/* Is there an outstanding layoutreturn ? */
1280	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1281		spin_unlock(&ino->i_lock);
1282		if (wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1283					TASK_UNINTERRUPTIBLE))
1284			goto out_put_layout_hdr;
1285		spin_lock(&ino->i_lock);
1286	}
1287	valid_layout = pnfs_layout_is_valid(lo);
1288	pnfs_clear_layoutcommit(ino, &tmp_list);
1289	pnfs_mark_matching_lsegs_invalid(lo, &tmp_list, NULL, 0);
1290
1291	if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) {
1292		struct pnfs_layout_range range = {
1293			.iomode		= IOMODE_ANY,
1294			.offset		= 0,
1295			.length		= NFS4_MAX_UINT64,
1296		};
1297		NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo, &range);
1298	}
1299
1300	/* Don't send a LAYOUTRETURN if list was initially empty */
1301	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) ||
1302			!valid_layout) {
1303		spin_unlock(&ino->i_lock);
1304		dprintk("NFS: %s no layout segments to return\n", __func__);
1305		goto out_put_layout_hdr;
1306	}
1307
1308	send = pnfs_prepare_layoutreturn(lo, &stateid, NULL);
1309	spin_unlock(&ino->i_lock);
1310	if (send)
1311		status = pnfs_send_layoutreturn(lo, &stateid, IOMODE_ANY, true);
 
 
1312out_put_layout_hdr:
1313	pnfs_free_lseg_list(&tmp_list);
1314	pnfs_put_layout_hdr(lo);
1315out:
1316	dprintk("<-- %s status: %d\n", __func__, status);
1317	return status;
1318}
1319
1320int
1321pnfs_commit_and_return_layout(struct inode *inode)
1322{
1323	struct pnfs_layout_hdr *lo;
1324	int ret;
1325
1326	spin_lock(&inode->i_lock);
1327	lo = NFS_I(inode)->layout;
1328	if (lo == NULL) {
1329		spin_unlock(&inode->i_lock);
1330		return 0;
1331	}
1332	pnfs_get_layout_hdr(lo);
1333	/* Block new layoutgets and read/write to ds */
1334	lo->plh_block_lgets++;
1335	spin_unlock(&inode->i_lock);
1336	filemap_fdatawait(inode->i_mapping);
1337	ret = pnfs_layoutcommit_inode(inode, true);
1338	if (ret == 0)
1339		ret = _pnfs_return_layout(inode);
1340	spin_lock(&inode->i_lock);
1341	lo->plh_block_lgets--;
1342	spin_unlock(&inode->i_lock);
1343	pnfs_put_layout_hdr(lo);
1344	return ret;
1345}
1346
1347bool pnfs_roc(struct inode *ino,
1348		struct nfs4_layoutreturn_args *args,
1349		struct nfs4_layoutreturn_res *res,
1350		const struct cred *cred)
1351{
1352	struct nfs_inode *nfsi = NFS_I(ino);
1353	struct nfs_open_context *ctx;
1354	struct nfs4_state *state;
1355	struct pnfs_layout_hdr *lo;
1356	struct pnfs_layout_segment *lseg, *next;
 
1357	nfs4_stateid stateid;
1358	enum pnfs_iomode iomode = 0;
1359	bool layoutreturn = false, roc = false;
1360	bool skip_read = false;
1361
1362	if (!nfs_have_layout(ino))
1363		return false;
1364retry:
1365	rcu_read_lock();
1366	spin_lock(&ino->i_lock);
1367	lo = nfsi->layout;
1368	if (!lo || !pnfs_layout_is_valid(lo) ||
1369	    test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1370		lo = NULL;
1371		goto out_noroc;
1372	}
1373	pnfs_get_layout_hdr(lo);
1374	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1375		spin_unlock(&ino->i_lock);
1376		rcu_read_unlock();
1377		wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1378				TASK_UNINTERRUPTIBLE);
1379		pnfs_put_layout_hdr(lo);
1380		goto retry;
1381	}
1382
1383	/* no roc if we hold a delegation */
1384	if (nfs4_check_delegation(ino, FMODE_READ)) {
1385		if (nfs4_check_delegation(ino, FMODE_WRITE))
1386			goto out_noroc;
1387		skip_read = true;
1388	}
1389
1390	list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
1391		state = ctx->state;
1392		if (state == NULL)
1393			continue;
1394		/* Don't return layout if there is open file state */
1395		if (state->state & FMODE_WRITE)
1396			goto out_noroc;
1397		if (state->state & FMODE_READ)
1398			skip_read = true;
1399	}
1400
1401
1402	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list) {
1403		if (skip_read && lseg->pls_range.iomode == IOMODE_READ)
1404			continue;
1405		/* If we are sending layoutreturn, invalidate all valid lsegs */
1406		if (!test_and_clear_bit(NFS_LSEG_ROC, &lseg->pls_flags))
1407			continue;
1408		/*
1409		 * Note: mark lseg for return so pnfs_layout_remove_lseg
1410		 * doesn't invalidate the layout for us.
1411		 */
1412		set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
1413		if (!mark_lseg_invalid(lseg, &lo->plh_return_segs))
1414			continue;
1415		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
1416	}
1417
1418	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1419		goto out_noroc;
1420
1421	/* ROC in two conditions:
1422	 * 1. there are ROC lsegs
1423	 * 2. we don't send layoutreturn
1424	 */
1425	/* lo ref dropped in pnfs_roc_release() */
1426	layoutreturn = pnfs_prepare_layoutreturn(lo, &stateid, &iomode);
1427	/* If the creds don't match, we can't compound the layoutreturn */
1428	if (!layoutreturn || cred != lo->plh_lc_cred)
1429		goto out_noroc;
1430
1431	roc = layoutreturn;
1432	pnfs_init_layoutreturn_args(args, lo, &stateid, iomode);
1433	res->lrs_present = 0;
1434	layoutreturn = false;
 
1435
1436out_noroc:
1437	spin_unlock(&ino->i_lock);
1438	rcu_read_unlock();
1439	pnfs_layoutcommit_inode(ino, true);
1440	if (roc) {
1441		struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1442		if (ld->prepare_layoutreturn)
1443			ld->prepare_layoutreturn(args);
1444		pnfs_put_layout_hdr(lo);
1445		return true;
1446	}
1447	if (layoutreturn)
1448		pnfs_send_layoutreturn(lo, &stateid, iomode, true);
1449	pnfs_put_layout_hdr(lo);
1450	return false;
1451}
1452
1453int pnfs_roc_done(struct rpc_task *task, struct inode *inode,
1454		struct nfs4_layoutreturn_args **argpp,
1455		struct nfs4_layoutreturn_res **respp,
1456		int *ret)
1457{
1458	struct nfs4_layoutreturn_args *arg = *argpp;
1459	int retval = -EAGAIN;
1460
1461	if (!arg)
1462		return 0;
1463	/* Handle Layoutreturn errors */
1464	switch (*ret) {
1465	case 0:
1466		retval = 0;
1467		break;
1468	case -NFS4ERR_NOMATCHING_LAYOUT:
1469		/* Was there an RPC level error? If not, retry */
1470		if (task->tk_rpc_status == 0)
1471			break;
1472		/* If the call was not sent, let caller handle it */
1473		if (!RPC_WAS_SENT(task))
1474			return 0;
1475		/*
1476		 * Otherwise, assume the call succeeded and
1477		 * that we need to release the layout
1478		 */
1479		*ret = 0;
1480		(*respp)->lrs_present = 0;
1481		retval = 0;
1482		break;
1483	case -NFS4ERR_DELAY:
1484		/* Let the caller handle the retry */
1485		*ret = -NFS4ERR_NOMATCHING_LAYOUT;
1486		return 0;
1487	case -NFS4ERR_OLD_STATEID:
1488		if (!nfs4_layout_refresh_old_stateid(&arg->stateid,
1489					&arg->range, inode))
1490			break;
1491		*ret = -NFS4ERR_NOMATCHING_LAYOUT;
1492		return -EAGAIN;
1493	}
1494	*argpp = NULL;
1495	*respp = NULL;
1496	return retval;
1497}
1498
1499void pnfs_roc_release(struct nfs4_layoutreturn_args *args,
1500		struct nfs4_layoutreturn_res *res,
1501		int ret)
1502{
1503	struct pnfs_layout_hdr *lo = args->layout;
1504	const nfs4_stateid *arg_stateid = NULL;
1505	const nfs4_stateid *res_stateid = NULL;
1506	struct nfs4_xdr_opaque_data *ld_private = args->ld_private;
1507
1508	switch (ret) {
1509	case -NFS4ERR_NOMATCHING_LAYOUT:
 
 
 
 
 
 
1510		break;
1511	case 0:
1512		if (res->lrs_present)
1513			res_stateid = &res->stateid;
1514		/* Fallthrough */
1515	default:
1516		arg_stateid = &args->stateid;
 
1517	}
1518	pnfs_layoutreturn_free_lsegs(lo, arg_stateid, &args->range,
1519			res_stateid);
1520	if (ld_private && ld_private->ops && ld_private->ops->free)
1521		ld_private->ops->free(ld_private);
1522	pnfs_put_layout_hdr(lo);
1523	trace_nfs4_layoutreturn_on_close(args->inode, 0);
1524}
1525
1526bool pnfs_wait_on_layoutreturn(struct inode *ino, struct rpc_task *task)
1527{
1528	struct nfs_inode *nfsi = NFS_I(ino);
1529        struct pnfs_layout_hdr *lo;
1530        bool sleep = false;
1531
1532	/* we might not have grabbed lo reference. so need to check under
1533	 * i_lock */
1534        spin_lock(&ino->i_lock);
1535        lo = nfsi->layout;
1536        if (lo && test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
1537                rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
1538                sleep = true;
1539	}
1540        spin_unlock(&ino->i_lock);
1541        return sleep;
1542}
1543
1544/*
1545 * Compare two layout segments for sorting into layout cache.
1546 * We want to preferentially return RW over RO layouts, so ensure those
1547 * are seen first.
1548 */
1549static s64
1550pnfs_lseg_range_cmp(const struct pnfs_layout_range *l1,
1551	   const struct pnfs_layout_range *l2)
1552{
1553	s64 d;
1554
1555	/* high offset > low offset */
1556	d = l1->offset - l2->offset;
1557	if (d)
1558		return d;
1559
1560	/* short length > long length */
1561	d = l2->length - l1->length;
1562	if (d)
1563		return d;
1564
1565	/* read > read/write */
1566	return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
1567}
1568
1569static bool
1570pnfs_lseg_range_is_after(const struct pnfs_layout_range *l1,
1571		const struct pnfs_layout_range *l2)
1572{
1573	return pnfs_lseg_range_cmp(l1, l2) > 0;
1574}
1575
1576static bool
1577pnfs_lseg_no_merge(struct pnfs_layout_segment *lseg,
1578		struct pnfs_layout_segment *old)
1579{
1580	return false;
1581}
1582
1583void
1584pnfs_generic_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1585		   struct pnfs_layout_segment *lseg,
1586		   bool (*is_after)(const struct pnfs_layout_range *,
1587			   const struct pnfs_layout_range *),
1588		   bool (*do_merge)(struct pnfs_layout_segment *,
1589			   struct pnfs_layout_segment *),
1590		   struct list_head *free_me)
1591{
1592	struct pnfs_layout_segment *lp, *tmp;
1593
1594	dprintk("%s:Begin\n", __func__);
1595
1596	list_for_each_entry_safe(lp, tmp, &lo->plh_segs, pls_list) {
1597		if (test_bit(NFS_LSEG_VALID, &lp->pls_flags) == 0)
1598			continue;
1599		if (do_merge(lseg, lp)) {
1600			mark_lseg_invalid(lp, free_me);
1601			continue;
1602		}
1603		if (is_after(&lseg->pls_range, &lp->pls_range))
1604			continue;
1605		list_add_tail(&lseg->pls_list, &lp->pls_list);
1606		dprintk("%s: inserted lseg %p "
1607			"iomode %d offset %llu length %llu before "
1608			"lp %p iomode %d offset %llu length %llu\n",
1609			__func__, lseg, lseg->pls_range.iomode,
1610			lseg->pls_range.offset, lseg->pls_range.length,
1611			lp, lp->pls_range.iomode, lp->pls_range.offset,
1612			lp->pls_range.length);
1613		goto out;
1614	}
1615	list_add_tail(&lseg->pls_list, &lo->plh_segs);
1616	dprintk("%s: inserted lseg %p "
1617		"iomode %d offset %llu length %llu at tail\n",
1618		__func__, lseg, lseg->pls_range.iomode,
1619		lseg->pls_range.offset, lseg->pls_range.length);
1620out:
1621	pnfs_get_layout_hdr(lo);
1622
1623	dprintk("%s:Return\n", __func__);
1624}
1625EXPORT_SYMBOL_GPL(pnfs_generic_layout_insert_lseg);
1626
1627static void
1628pnfs_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1629		   struct pnfs_layout_segment *lseg,
1630		   struct list_head *free_me)
1631{
1632	struct inode *inode = lo->plh_inode;
1633	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
1634
1635	if (ld->add_lseg != NULL)
1636		ld->add_lseg(lo, lseg, free_me);
1637	else
1638		pnfs_generic_layout_insert_lseg(lo, lseg,
1639				pnfs_lseg_range_is_after,
1640				pnfs_lseg_no_merge,
1641				free_me);
1642}
1643
1644static struct pnfs_layout_hdr *
1645alloc_init_layout_hdr(struct inode *ino,
1646		      struct nfs_open_context *ctx,
1647		      gfp_t gfp_flags)
1648{
1649	struct pnfs_layout_hdr *lo;
1650
1651	lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
1652	if (!lo)
1653		return NULL;
1654	refcount_set(&lo->plh_refcount, 1);
1655	INIT_LIST_HEAD(&lo->plh_layouts);
1656	INIT_LIST_HEAD(&lo->plh_segs);
1657	INIT_LIST_HEAD(&lo->plh_return_segs);
1658	INIT_LIST_HEAD(&lo->plh_bulk_destroy);
1659	lo->plh_inode = ino;
1660	lo->plh_lc_cred = get_cred(ctx->cred);
1661	lo->plh_flags |= 1 << NFS_LAYOUT_INVALID_STID;
1662	return lo;
1663}
1664
1665static struct pnfs_layout_hdr *
1666pnfs_find_alloc_layout(struct inode *ino,
1667		       struct nfs_open_context *ctx,
1668		       gfp_t gfp_flags)
1669	__releases(&ino->i_lock)
1670	__acquires(&ino->i_lock)
1671{
1672	struct nfs_inode *nfsi = NFS_I(ino);
1673	struct pnfs_layout_hdr *new = NULL;
1674
1675	dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
1676
1677	if (nfsi->layout != NULL)
1678		goto out_existing;
1679	spin_unlock(&ino->i_lock);
1680	new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
1681	spin_lock(&ino->i_lock);
1682
1683	if (likely(nfsi->layout == NULL)) {	/* Won the race? */
1684		nfsi->layout = new;
1685		return new;
1686	} else if (new != NULL)
1687		pnfs_free_layout_hdr(new);
1688out_existing:
1689	pnfs_get_layout_hdr(nfsi->layout);
1690	return nfsi->layout;
1691}
1692
1693/*
1694 * iomode matching rules:
1695 * iomode	lseg	strict match
1696 *                      iomode
1697 * -----	-----	------ -----
1698 * ANY		READ	N/A    true
1699 * ANY		RW	N/A    true
1700 * RW		READ	N/A    false
1701 * RW		RW	N/A    true
1702 * READ		READ	N/A    true
1703 * READ		RW	true   false
1704 * READ		RW	false  true
1705 */
1706static bool
1707pnfs_lseg_range_match(const struct pnfs_layout_range *ls_range,
1708		 const struct pnfs_layout_range *range,
1709		 bool strict_iomode)
1710{
1711	struct pnfs_layout_range range1;
1712
1713	if ((range->iomode == IOMODE_RW &&
1714	     ls_range->iomode != IOMODE_RW) ||
1715	    (range->iomode != ls_range->iomode &&
1716	     strict_iomode) ||
1717	    !pnfs_lseg_range_intersecting(ls_range, range))
1718		return false;
1719
1720	/* range1 covers only the first byte in the range */
1721	range1 = *range;
1722	range1.length = 1;
1723	return pnfs_lseg_range_contained(ls_range, &range1);
1724}
1725
1726/*
1727 * lookup range in layout
1728 */
1729static struct pnfs_layout_segment *
1730pnfs_find_lseg(struct pnfs_layout_hdr *lo,
1731		struct pnfs_layout_range *range,
1732		bool strict_iomode)
1733{
1734	struct pnfs_layout_segment *lseg, *ret = NULL;
1735
1736	dprintk("%s:Begin\n", __func__);
1737
1738	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
1739		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
1740		    pnfs_lseg_range_match(&lseg->pls_range, range,
1741					  strict_iomode)) {
1742			ret = pnfs_get_lseg(lseg);
1743			break;
1744		}
1745	}
1746
1747	dprintk("%s:Return lseg %p ref %d\n",
1748		__func__, ret, ret ? refcount_read(&ret->pls_refcount) : 0);
1749	return ret;
1750}
1751
1752/*
1753 * Use mdsthreshold hints set at each OPEN to determine if I/O should go
1754 * to the MDS or over pNFS
1755 *
1756 * The nfs_inode read_io and write_io fields are cumulative counters reset
1757 * when there are no layout segments. Note that in pnfs_update_layout iomode
1758 * is set to IOMODE_READ for a READ request, and set to IOMODE_RW for a
1759 * WRITE request.
1760 *
1761 * A return of true means use MDS I/O.
1762 *
1763 * From rfc 5661:
1764 * If a file's size is smaller than the file size threshold, data accesses
1765 * SHOULD be sent to the metadata server.  If an I/O request has a length that
1766 * is below the I/O size threshold, the I/O SHOULD be sent to the metadata
1767 * server.  If both file size and I/O size are provided, the client SHOULD
1768 * reach or exceed  both thresholds before sending its read or write
1769 * requests to the data server.
1770 */
1771static bool pnfs_within_mdsthreshold(struct nfs_open_context *ctx,
1772				     struct inode *ino, int iomode)
1773{
1774	struct nfs4_threshold *t = ctx->mdsthreshold;
1775	struct nfs_inode *nfsi = NFS_I(ino);
1776	loff_t fsize = i_size_read(ino);
1777	bool size = false, size_set = false, io = false, io_set = false, ret = false;
1778
1779	if (t == NULL)
1780		return ret;
1781
1782	dprintk("%s bm=0x%x rd_sz=%llu wr_sz=%llu rd_io=%llu wr_io=%llu\n",
1783		__func__, t->bm, t->rd_sz, t->wr_sz, t->rd_io_sz, t->wr_io_sz);
1784
1785	switch (iomode) {
1786	case IOMODE_READ:
1787		if (t->bm & THRESHOLD_RD) {
1788			dprintk("%s fsize %llu\n", __func__, fsize);
1789			size_set = true;
1790			if (fsize < t->rd_sz)
1791				size = true;
1792		}
1793		if (t->bm & THRESHOLD_RD_IO) {
1794			dprintk("%s nfsi->read_io %llu\n", __func__,
1795				nfsi->read_io);
1796			io_set = true;
1797			if (nfsi->read_io < t->rd_io_sz)
1798				io = true;
1799		}
1800		break;
1801	case IOMODE_RW:
1802		if (t->bm & THRESHOLD_WR) {
1803			dprintk("%s fsize %llu\n", __func__, fsize);
1804			size_set = true;
1805			if (fsize < t->wr_sz)
1806				size = true;
1807		}
1808		if (t->bm & THRESHOLD_WR_IO) {
1809			dprintk("%s nfsi->write_io %llu\n", __func__,
1810				nfsi->write_io);
1811			io_set = true;
1812			if (nfsi->write_io < t->wr_io_sz)
1813				io = true;
1814		}
1815		break;
1816	}
1817	if (size_set && io_set) {
1818		if (size && io)
1819			ret = true;
1820	} else if (size || io)
1821		ret = true;
1822
1823	dprintk("<-- %s size %d io %d ret %d\n", __func__, size, io, ret);
1824	return ret;
1825}
1826
1827static int pnfs_prepare_to_retry_layoutget(struct pnfs_layout_hdr *lo)
1828{
1829	/*
1830	 * send layoutcommit as it can hold up layoutreturn due to lseg
1831	 * reference
1832	 */
1833	pnfs_layoutcommit_inode(lo->plh_inode, false);
1834	return wait_on_bit_action(&lo->plh_flags, NFS_LAYOUT_RETURN,
1835				   nfs_wait_bit_killable,
1836				   TASK_KILLABLE);
1837}
1838
1839static void nfs_layoutget_begin(struct pnfs_layout_hdr *lo)
1840{
1841	atomic_inc(&lo->plh_outstanding);
1842}
1843
1844static void nfs_layoutget_end(struct pnfs_layout_hdr *lo)
1845{
1846	if (atomic_dec_and_test(&lo->plh_outstanding))
1847		wake_up_var(&lo->plh_outstanding);
1848}
1849
 
 
 
 
 
1850static void pnfs_clear_first_layoutget(struct pnfs_layout_hdr *lo)
1851{
1852	unsigned long *bitlock = &lo->plh_flags;
1853
1854	clear_bit_unlock(NFS_LAYOUT_FIRST_LAYOUTGET, bitlock);
1855	smp_mb__after_atomic();
1856	wake_up_bit(bitlock, NFS_LAYOUT_FIRST_LAYOUTGET);
1857}
1858
1859static void _add_to_server_list(struct pnfs_layout_hdr *lo,
1860				struct nfs_server *server)
1861{
1862	if (list_empty(&lo->plh_layouts)) {
1863		struct nfs_client *clp = server->nfs_client;
1864
1865		/* The lo must be on the clp list if there is any
1866		 * chance of a CB_LAYOUTRECALL(FILE) coming in.
1867		 */
1868		spin_lock(&clp->cl_lock);
1869		if (list_empty(&lo->plh_layouts))
1870			list_add_tail(&lo->plh_layouts, &server->layouts);
1871		spin_unlock(&clp->cl_lock);
1872	}
1873}
1874
1875/*
1876 * Layout segment is retreived from the server if not cached.
1877 * The appropriate layout segment is referenced and returned to the caller.
1878 */
1879struct pnfs_layout_segment *
1880pnfs_update_layout(struct inode *ino,
1881		   struct nfs_open_context *ctx,
1882		   loff_t pos,
1883		   u64 count,
1884		   enum pnfs_iomode iomode,
1885		   bool strict_iomode,
1886		   gfp_t gfp_flags)
1887{
1888	struct pnfs_layout_range arg = {
1889		.iomode = iomode,
1890		.offset = pos,
1891		.length = count,
1892	};
1893	unsigned pg_offset;
1894	struct nfs_server *server = NFS_SERVER(ino);
1895	struct nfs_client *clp = server->nfs_client;
1896	struct pnfs_layout_hdr *lo = NULL;
1897	struct pnfs_layout_segment *lseg = NULL;
1898	struct nfs4_layoutget *lgp;
1899	nfs4_stateid stateid;
1900	long timeout = 0;
1901	unsigned long giveup = jiffies + (clp->cl_lease_time << 1);
1902	bool first;
1903
1904	if (!pnfs_enabled_sb(NFS_SERVER(ino))) {
1905		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1906				 PNFS_UPDATE_LAYOUT_NO_PNFS);
1907		goto out;
1908	}
1909
1910	if (pnfs_within_mdsthreshold(ctx, ino, iomode)) {
1911		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1912				 PNFS_UPDATE_LAYOUT_MDSTHRESH);
1913		goto out;
1914	}
1915
1916lookup_again:
1917	lseg = ERR_PTR(nfs4_client_recover_expired_lease(clp));
1918	if (IS_ERR(lseg))
1919		goto out;
1920	first = false;
1921	spin_lock(&ino->i_lock);
1922	lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
1923	if (lo == NULL) {
1924		spin_unlock(&ino->i_lock);
1925		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1926				 PNFS_UPDATE_LAYOUT_NOMEM);
1927		goto out;
1928	}
1929
1930	/* Do we even need to bother with this? */
1931	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1932		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1933				 PNFS_UPDATE_LAYOUT_BULK_RECALL);
1934		dprintk("%s matches recall, use MDS\n", __func__);
1935		goto out_unlock;
1936	}
1937
1938	/* if LAYOUTGET already failed once we don't try again */
1939	if (pnfs_layout_io_test_failed(lo, iomode)) {
1940		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1941				 PNFS_UPDATE_LAYOUT_IO_TEST_FAIL);
1942		goto out_unlock;
1943	}
1944
1945	/*
1946	 * If the layout segment list is empty, but there are outstanding
1947	 * layoutget calls, then they might be subject to a layoutrecall.
1948	 */
1949	if (list_empty(&lo->plh_segs) &&
1950	    atomic_read(&lo->plh_outstanding) != 0) {
1951		spin_unlock(&ino->i_lock);
1952		lseg = ERR_PTR(wait_var_event_killable(&lo->plh_outstanding,
1953					!atomic_read(&lo->plh_outstanding)));
1954		if (IS_ERR(lseg))
1955			goto out_put_layout_hdr;
1956		pnfs_put_layout_hdr(lo);
1957		goto lookup_again;
1958	}
1959
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1960	lseg = pnfs_find_lseg(lo, &arg, strict_iomode);
1961	if (lseg) {
1962		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1963				PNFS_UPDATE_LAYOUT_FOUND_CACHED);
1964		goto out_unlock;
1965	}
1966
1967	/*
1968	 * Choose a stateid for the LAYOUTGET. If we don't have a layout
1969	 * stateid, or it has been invalidated, then we must use the open
1970	 * stateid.
1971	 */
1972	if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags)) {
1973		int status;
1974
1975		/*
1976		 * The first layoutget for the file. Need to serialize per
1977		 * RFC 5661 Errata 3208.
1978		 */
1979		if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET,
1980				     &lo->plh_flags)) {
1981			spin_unlock(&ino->i_lock);
1982			lseg = ERR_PTR(wait_on_bit(&lo->plh_flags,
1983						NFS_LAYOUT_FIRST_LAYOUTGET,
1984						TASK_KILLABLE));
1985			if (IS_ERR(lseg))
1986				goto out_put_layout_hdr;
1987			pnfs_put_layout_hdr(lo);
1988			dprintk("%s retrying\n", __func__);
1989			goto lookup_again;
1990		}
1991
 
1992		first = true;
1993		status = nfs4_select_rw_stateid(ctx->state,
1994					iomode == IOMODE_RW ? FMODE_WRITE : FMODE_READ,
1995					NULL, &stateid, NULL);
1996		if (status != 0) {
1997			lseg = ERR_PTR(status);
1998			trace_pnfs_update_layout(ino, pos, count,
1999					iomode, lo, lseg,
2000					PNFS_UPDATE_LAYOUT_INVALID_OPEN);
2001			if (status != -EAGAIN)
2002				goto out_unlock;
2003			spin_unlock(&ino->i_lock);
2004			nfs4_schedule_stateid_recovery(server, ctx->state);
2005			pnfs_clear_first_layoutget(lo);
2006			pnfs_put_layout_hdr(lo);
2007			goto lookup_again;
2008		}
 
2009	} else {
2010		nfs4_stateid_copy(&stateid, &lo->plh_stateid);
2011	}
2012
2013	/*
2014	 * Because we free lsegs before sending LAYOUTRETURN, we need to wait
2015	 * for LAYOUTRETURN even if first is true.
2016	 */
2017	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
2018		spin_unlock(&ino->i_lock);
2019		dprintk("%s wait for layoutreturn\n", __func__);
2020		lseg = ERR_PTR(pnfs_prepare_to_retry_layoutget(lo));
2021		if (!IS_ERR(lseg)) {
2022			if (first)
2023				pnfs_clear_first_layoutget(lo);
2024			pnfs_put_layout_hdr(lo);
2025			dprintk("%s retrying\n", __func__);
2026			trace_pnfs_update_layout(ino, pos, count, iomode, lo,
2027					lseg, PNFS_UPDATE_LAYOUT_RETRY);
2028			goto lookup_again;
2029		}
2030		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2031				PNFS_UPDATE_LAYOUT_RETURN);
2032		goto out_put_layout_hdr;
2033	}
2034
2035	if (pnfs_layoutgets_blocked(lo)) {
2036		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2037				PNFS_UPDATE_LAYOUT_BLOCKED);
2038		goto out_unlock;
2039	}
2040	nfs_layoutget_begin(lo);
2041	spin_unlock(&ino->i_lock);
2042
2043	_add_to_server_list(lo, server);
2044
2045	pg_offset = arg.offset & ~PAGE_MASK;
2046	if (pg_offset) {
2047		arg.offset -= pg_offset;
2048		arg.length += pg_offset;
2049	}
2050	if (arg.length != NFS4_MAX_UINT64)
2051		arg.length = PAGE_ALIGN(arg.length);
2052
2053	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &stateid, &arg, gfp_flags);
2054	if (!lgp) {
2055		trace_pnfs_update_layout(ino, pos, count, iomode, lo, NULL,
2056					 PNFS_UPDATE_LAYOUT_NOMEM);
2057		nfs_layoutget_end(lo);
2058		goto out_put_layout_hdr;
2059	}
2060
 
 
 
2061	lseg = nfs4_proc_layoutget(lgp, &timeout);
2062	trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2063				 PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET);
2064	nfs_layoutget_end(lo);
2065	if (IS_ERR(lseg)) {
2066		switch(PTR_ERR(lseg)) {
2067		case -EBUSY:
2068			if (time_after(jiffies, giveup))
2069				lseg = NULL;
2070			break;
2071		case -ERECALLCONFLICT:
2072		case -EAGAIN:
2073			break;
2074		default:
2075			if (!nfs_error_is_fatal(PTR_ERR(lseg))) {
2076				pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2077				lseg = NULL;
2078			}
2079			goto out_put_layout_hdr;
2080		}
2081		if (lseg) {
2082			if (first)
2083				pnfs_clear_first_layoutget(lo);
2084			trace_pnfs_update_layout(ino, pos, count,
2085				iomode, lo, lseg, PNFS_UPDATE_LAYOUT_RETRY);
2086			pnfs_put_layout_hdr(lo);
2087			goto lookup_again;
2088		}
2089	} else {
2090		pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2091	}
2092
2093out_put_layout_hdr:
2094	if (first)
2095		pnfs_clear_first_layoutget(lo);
2096	trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2097				 PNFS_UPDATE_LAYOUT_EXIT);
2098	pnfs_put_layout_hdr(lo);
2099out:
2100	dprintk("%s: inode %s/%llu pNFS layout segment %s for "
2101			"(%s, offset: %llu, length: %llu)\n",
2102			__func__, ino->i_sb->s_id,
2103			(unsigned long long)NFS_FILEID(ino),
2104			IS_ERR_OR_NULL(lseg) ? "not found" : "found",
2105			iomode==IOMODE_RW ?  "read/write" : "read-only",
2106			(unsigned long long)pos,
2107			(unsigned long long)count);
2108	return lseg;
2109out_unlock:
2110	spin_unlock(&ino->i_lock);
2111	goto out_put_layout_hdr;
2112}
2113EXPORT_SYMBOL_GPL(pnfs_update_layout);
2114
2115static bool
2116pnfs_sanity_check_layout_range(struct pnfs_layout_range *range)
2117{
2118	switch (range->iomode) {
2119	case IOMODE_READ:
2120	case IOMODE_RW:
2121		break;
2122	default:
2123		return false;
2124	}
2125	if (range->offset == NFS4_MAX_UINT64)
2126		return false;
2127	if (range->length == 0)
2128		return false;
2129	if (range->length != NFS4_MAX_UINT64 &&
2130	    range->length > NFS4_MAX_UINT64 - range->offset)
2131		return false;
2132	return true;
2133}
2134
2135static struct pnfs_layout_hdr *
2136_pnfs_grab_empty_layout(struct inode *ino, struct nfs_open_context *ctx)
2137{
2138	struct pnfs_layout_hdr *lo;
2139
2140	spin_lock(&ino->i_lock);
2141	lo = pnfs_find_alloc_layout(ino, ctx, GFP_KERNEL);
2142	if (!lo)
2143		goto out_unlock;
2144	if (!test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags))
2145		goto out_unlock;
2146	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
2147		goto out_unlock;
2148	if (pnfs_layoutgets_blocked(lo))
2149		goto out_unlock;
2150	if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET, &lo->plh_flags))
2151		goto out_unlock;
2152	nfs_layoutget_begin(lo);
2153	spin_unlock(&ino->i_lock);
2154	_add_to_server_list(lo, NFS_SERVER(ino));
2155	return lo;
2156
2157out_unlock:
2158	spin_unlock(&ino->i_lock);
2159	pnfs_put_layout_hdr(lo);
2160	return NULL;
2161}
2162
2163extern const nfs4_stateid current_stateid;
2164
2165static void _lgopen_prepare_attached(struct nfs4_opendata *data,
2166				     struct nfs_open_context *ctx)
2167{
2168	struct inode *ino = data->dentry->d_inode;
2169	struct pnfs_layout_range rng = {
2170		.iomode = (data->o_arg.fmode & FMODE_WRITE) ?
2171			  IOMODE_RW: IOMODE_READ,
2172		.offset = 0,
2173		.length = NFS4_MAX_UINT64,
2174	};
2175	struct nfs4_layoutget *lgp;
2176	struct pnfs_layout_hdr *lo;
2177
2178	/* Heuristic: don't send layoutget if we have cached data */
2179	if (rng.iomode == IOMODE_READ &&
2180	   (i_size_read(ino) == 0 || ino->i_mapping->nrpages != 0))
2181		return;
2182
2183	lo = _pnfs_grab_empty_layout(ino, ctx);
2184	if (!lo)
2185		return;
2186	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &current_stateid,
2187					     &rng, GFP_KERNEL);
2188	if (!lgp) {
2189		pnfs_clear_first_layoutget(lo);
 
2190		pnfs_put_layout_hdr(lo);
2191		return;
2192	}
 
2193	data->lgp = lgp;
2194	data->o_arg.lg_args = &lgp->args;
2195	data->o_res.lg_res = &lgp->res;
2196}
2197
2198static void _lgopen_prepare_floating(struct nfs4_opendata *data,
2199				     struct nfs_open_context *ctx)
2200{
 
2201	struct pnfs_layout_range rng = {
2202		.iomode = (data->o_arg.fmode & FMODE_WRITE) ?
2203			  IOMODE_RW: IOMODE_READ,
2204		.offset = 0,
2205		.length = NFS4_MAX_UINT64,
2206	};
2207	struct nfs4_layoutget *lgp;
2208
2209	lgp = pnfs_alloc_init_layoutget_args(NULL, ctx, &current_stateid,
2210					     &rng, GFP_KERNEL);
2211	if (!lgp)
2212		return;
2213	data->lgp = lgp;
2214	data->o_arg.lg_args = &lgp->args;
2215	data->o_res.lg_res = &lgp->res;
2216}
2217
2218void pnfs_lgopen_prepare(struct nfs4_opendata *data,
2219			 struct nfs_open_context *ctx)
2220{
2221	struct nfs_server *server = NFS_SERVER(data->dir->d_inode);
2222
2223	if (!(pnfs_enabled_sb(server) &&
2224	      server->pnfs_curr_ld->flags & PNFS_LAYOUTGET_ON_OPEN))
2225		return;
2226	/* Could check on max_ops, but currently hardcoded high enough */
2227	if (!nfs_server_capable(data->dir->d_inode, NFS_CAP_LGOPEN))
2228		return;
 
 
2229	if (data->state)
2230		_lgopen_prepare_attached(data, ctx);
2231	else
2232		_lgopen_prepare_floating(data, ctx);
2233}
2234
2235void pnfs_parse_lgopen(struct inode *ino, struct nfs4_layoutget *lgp,
2236		       struct nfs_open_context *ctx)
2237{
2238	struct pnfs_layout_hdr *lo;
2239	struct pnfs_layout_segment *lseg;
2240	struct nfs_server *srv = NFS_SERVER(ino);
2241	u32 iomode;
2242
2243	if (!lgp)
2244		return;
2245	dprintk("%s: entered with status %i\n", __func__, lgp->res.status);
2246	if (lgp->res.status) {
2247		switch (lgp->res.status) {
2248		default:
2249			break;
2250		/*
2251		 * Halt lgopen attempts if the server doesn't recognise
2252		 * the "current stateid" value, the layout type, or the
2253		 * layoutget operation as being valid.
2254		 * Also if it complains about too many ops in the compound
2255		 * or of the request/reply being too big.
2256		 */
2257		case -NFS4ERR_BAD_STATEID:
2258		case -NFS4ERR_NOTSUPP:
2259		case -NFS4ERR_REP_TOO_BIG:
2260		case -NFS4ERR_REP_TOO_BIG_TO_CACHE:
2261		case -NFS4ERR_REQ_TOO_BIG:
2262		case -NFS4ERR_TOO_MANY_OPS:
2263		case -NFS4ERR_UNKNOWN_LAYOUTTYPE:
2264			srv->caps &= ~NFS_CAP_LGOPEN;
2265		}
2266		return;
2267	}
2268	if (!lgp->args.inode) {
2269		lo = _pnfs_grab_empty_layout(ino, ctx);
2270		if (!lo)
2271			return;
2272		lgp->args.inode = ino;
2273	} else
2274		lo = NFS_I(lgp->args.inode)->layout;
2275
2276	lseg = pnfs_layout_process(lgp);
2277	if (!IS_ERR(lseg)) {
2278		iomode = lgp->args.range.iomode;
2279		pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2280		pnfs_put_lseg(lseg);
2281	}
2282}
2283
2284void nfs4_lgopen_release(struct nfs4_layoutget *lgp)
2285{
2286	if (lgp != NULL) {
2287		struct inode *inode = lgp->args.inode;
2288		if (inode) {
2289			struct pnfs_layout_hdr *lo = NFS_I(inode)->layout;
2290			pnfs_clear_first_layoutget(lo);
2291			nfs_layoutget_end(lo);
2292		}
2293		pnfs_layoutget_free(lgp);
2294	}
2295}
2296
2297struct pnfs_layout_segment *
2298pnfs_layout_process(struct nfs4_layoutget *lgp)
2299{
2300	struct pnfs_layout_hdr *lo = NFS_I(lgp->args.inode)->layout;
2301	struct nfs4_layoutget_res *res = &lgp->res;
2302	struct pnfs_layout_segment *lseg;
2303	struct inode *ino = lo->plh_inode;
2304	LIST_HEAD(free_me);
2305
2306	if (!pnfs_sanity_check_layout_range(&res->range))
2307		return ERR_PTR(-EINVAL);
2308
2309	/* Inject layout blob into I/O device driver */
2310	lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
2311	if (IS_ERR_OR_NULL(lseg)) {
2312		if (!lseg)
2313			lseg = ERR_PTR(-ENOMEM);
2314
2315		dprintk("%s: Could not allocate layout: error %ld\n",
2316		       __func__, PTR_ERR(lseg));
2317		return lseg;
2318	}
2319
2320	pnfs_init_lseg(lo, lseg, &res->range, &res->stateid);
2321
2322	spin_lock(&ino->i_lock);
2323	if (pnfs_layoutgets_blocked(lo)) {
2324		dprintk("%s forget reply due to state\n", __func__);
2325		goto out_forget;
2326	}
2327
2328	if (!pnfs_layout_is_valid(lo)) {
2329		/* We have a completely new layout */
2330		pnfs_set_layout_stateid(lo, &res->stateid, true);
2331	} else if (nfs4_stateid_match_other(&lo->plh_stateid, &res->stateid)) {
2332		/* existing state ID, make sure the sequence number matches. */
2333		if (pnfs_layout_stateid_blocked(lo, &res->stateid)) {
 
 
2334			dprintk("%s forget reply due to sequence\n", __func__);
2335			goto out_forget;
2336		}
2337		pnfs_set_layout_stateid(lo, &res->stateid, false);
2338	} else {
2339		/*
2340		 * We got an entirely new state ID.  Mark all segments for the
2341		 * inode invalid, and retry the layoutget
2342		 */
2343		pnfs_mark_layout_stateid_invalid(lo, &free_me);
 
 
 
 
2344		goto out_forget;
 
 
 
2345	}
2346
2347	pnfs_get_lseg(lseg);
2348	pnfs_layout_insert_lseg(lo, lseg, &free_me);
2349
2350
2351	if (res->return_on_close)
2352		set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
2353
2354	spin_unlock(&ino->i_lock);
2355	pnfs_free_lseg_list(&free_me);
2356	return lseg;
2357
2358out_forget:
2359	spin_unlock(&ino->i_lock);
2360	lseg->pls_layout = lo;
2361	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
2362	return ERR_PTR(-EAGAIN);
2363}
2364
2365static int
2366mark_lseg_invalid_or_return(struct pnfs_layout_segment *lseg,
2367		struct list_head *tmp_list)
2368{
2369	if (!mark_lseg_invalid(lseg, tmp_list))
2370		return 0;
2371	pnfs_cache_lseg_for_layoutreturn(lseg->pls_layout, lseg);
2372	return 1;
2373}
2374
2375/**
2376 * pnfs_mark_matching_lsegs_return - Free or return matching layout segments
2377 * @lo: pointer to layout header
2378 * @tmp_list: list header to be used with pnfs_free_lseg_list()
2379 * @return_range: describe layout segment ranges to be returned
2380 * @seq: stateid seqid to match
2381 *
2382 * This function is mainly intended for use by layoutrecall. It attempts
2383 * to free the layout segment immediately, or else to mark it for return
2384 * as soon as its reference count drops to zero.
2385 *
2386 * Returns
2387 * - 0: a layoutreturn needs to be scheduled.
2388 * - EBUSY: there are layout segment that are still in use.
2389 * - ENOENT: there are no layout segments that need to be returned.
2390 */
2391int
2392pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
2393				struct list_head *tmp_list,
2394				const struct pnfs_layout_range *return_range,
2395				u32 seq)
2396{
2397	struct pnfs_layout_segment *lseg, *next;
2398	int remaining = 0;
2399
2400	dprintk("%s:Begin lo %p\n", __func__, lo);
2401
2402	assert_spin_locked(&lo->plh_inode->i_lock);
2403
 
 
 
2404	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
2405		if (pnfs_match_lseg_recall(lseg, return_range, seq)) {
2406			dprintk("%s: marking lseg %p iomode %d "
2407				"offset %llu length %llu\n", __func__,
2408				lseg, lseg->pls_range.iomode,
2409				lseg->pls_range.offset,
2410				lseg->pls_range.length);
2411			if (mark_lseg_invalid_or_return(lseg, tmp_list))
 
 
2412				continue;
2413			remaining++;
2414			set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
2415		}
2416
2417	if (remaining) {
2418		pnfs_set_plh_return_info(lo, return_range->iomode, seq);
2419		return -EBUSY;
2420	}
2421
2422	if (!list_empty(&lo->plh_return_segs)) {
2423		pnfs_set_plh_return_info(lo, return_range->iomode, seq);
2424		return 0;
2425	}
2426
2427	return -ENOENT;
2428}
2429
2430void pnfs_error_mark_layout_for_return(struct inode *inode,
2431				       struct pnfs_layout_segment *lseg)
 
2432{
2433	struct pnfs_layout_hdr *lo = NFS_I(inode)->layout;
2434	struct pnfs_layout_range range = {
2435		.iomode = lseg->pls_range.iomode,
2436		.offset = 0,
2437		.length = NFS4_MAX_UINT64,
2438	};
2439	bool return_now = false;
2440
2441	spin_lock(&inode->i_lock);
 
2442	if (!pnfs_layout_is_valid(lo)) {
2443		spin_unlock(&inode->i_lock);
2444		return;
2445	}
2446	pnfs_set_plh_return_info(lo, range.iomode, 0);
2447	/*
2448	 * mark all matching lsegs so that we are sure to have no live
2449	 * segments at hand when sending layoutreturn. See pnfs_put_lseg()
2450	 * for how it works.
2451	 */
2452	if (pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs, &range, 0) != -EBUSY) {
 
2453		nfs4_stateid stateid;
2454		enum pnfs_iomode iomode;
2455
2456		return_now = pnfs_prepare_layoutreturn(lo, &stateid, &iomode);
2457		spin_unlock(&inode->i_lock);
2458		if (return_now)
2459			pnfs_send_layoutreturn(lo, &stateid, iomode, false);
2460	} else {
2461		spin_unlock(&inode->i_lock);
2462		nfs_commit_inode(inode, 0);
2463	}
2464}
 
 
 
 
 
 
 
 
 
 
 
 
2465EXPORT_SYMBOL_GPL(pnfs_error_mark_layout_for_return);
2466
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2467void
2468pnfs_generic_pg_check_layout(struct nfs_pageio_descriptor *pgio)
2469{
2470	if (pgio->pg_lseg == NULL ||
2471	    test_bit(NFS_LSEG_VALID, &pgio->pg_lseg->pls_flags))
2472		return;
2473	pnfs_put_lseg(pgio->pg_lseg);
2474	pgio->pg_lseg = NULL;
2475}
2476EXPORT_SYMBOL_GPL(pnfs_generic_pg_check_layout);
2477
2478/*
2479 * Check for any intersection between the request and the pgio->pg_lseg,
2480 * and if none, put this pgio->pg_lseg away.
2481 */
2482static void
2483pnfs_generic_pg_check_range(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
2484{
2485	if (pgio->pg_lseg && !pnfs_lseg_request_intersecting(pgio->pg_lseg, req)) {
2486		pnfs_put_lseg(pgio->pg_lseg);
2487		pgio->pg_lseg = NULL;
2488	}
2489}
 
2490
2491void
2492pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
2493{
2494	u64 rd_size = req->wb_bytes;
2495
2496	pnfs_generic_pg_check_layout(pgio);
2497	pnfs_generic_pg_check_range(pgio, req);
2498	if (pgio->pg_lseg == NULL) {
2499		if (pgio->pg_dreq == NULL)
2500			rd_size = i_size_read(pgio->pg_inode) - req_offset(req);
2501		else
2502			rd_size = nfs_dreq_bytes_left(pgio->pg_dreq);
2503
2504		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
2505						   nfs_req_openctx(req),
2506						   req_offset(req),
2507						   rd_size,
2508						   IOMODE_READ,
2509						   false,
2510						   GFP_KERNEL);
2511		if (IS_ERR(pgio->pg_lseg)) {
2512			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2513			pgio->pg_lseg = NULL;
2514			return;
2515		}
2516	}
2517	/* If no lseg, fall back to read through mds */
2518	if (pgio->pg_lseg == NULL)
2519		nfs_pageio_reset_read_mds(pgio);
2520
2521}
2522EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);
2523
2524void
2525pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
2526			   struct nfs_page *req, u64 wb_size)
2527{
2528	pnfs_generic_pg_check_layout(pgio);
2529	pnfs_generic_pg_check_range(pgio, req);
2530	if (pgio->pg_lseg == NULL) {
2531		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
2532						   nfs_req_openctx(req),
2533						   req_offset(req),
2534						   wb_size,
2535						   IOMODE_RW,
2536						   false,
2537						   GFP_KERNEL);
2538		if (IS_ERR(pgio->pg_lseg)) {
2539			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2540			pgio->pg_lseg = NULL;
2541			return;
2542		}
2543	}
2544	/* If no lseg, fall back to write through mds */
2545	if (pgio->pg_lseg == NULL)
2546		nfs_pageio_reset_write_mds(pgio);
2547}
2548EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
2549
2550void
2551pnfs_generic_pg_cleanup(struct nfs_pageio_descriptor *desc)
2552{
2553	if (desc->pg_lseg) {
2554		pnfs_put_lseg(desc->pg_lseg);
2555		desc->pg_lseg = NULL;
2556	}
2557}
2558EXPORT_SYMBOL_GPL(pnfs_generic_pg_cleanup);
2559
2560/*
2561 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
2562 * of bytes (maximum @req->wb_bytes) that can be coalesced.
2563 */
2564size_t
2565pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio,
2566		     struct nfs_page *prev, struct nfs_page *req)
2567{
2568	unsigned int size;
2569	u64 seg_end, req_start, seg_left;
2570
2571	size = nfs_generic_pg_test(pgio, prev, req);
2572	if (!size)
2573		return 0;
2574
2575	/*
2576	 * 'size' contains the number of bytes left in the current page (up
2577	 * to the original size asked for in @req->wb_bytes).
2578	 *
2579	 * Calculate how many bytes are left in the layout segment
2580	 * and if there are less bytes than 'size', return that instead.
2581	 *
2582	 * Please also note that 'end_offset' is actually the offset of the
2583	 * first byte that lies outside the pnfs_layout_range. FIXME?
2584	 *
2585	 */
2586	if (pgio->pg_lseg) {
2587		seg_end = pnfs_end_offset(pgio->pg_lseg->pls_range.offset,
2588				     pgio->pg_lseg->pls_range.length);
2589		req_start = req_offset(req);
2590
2591		/* start of request is past the last byte of this segment */
2592		if (req_start >= seg_end)
2593			return 0;
2594
2595		/* adjust 'size' iff there are fewer bytes left in the
2596		 * segment than what nfs_generic_pg_test returned */
2597		seg_left = seg_end - req_start;
2598		if (seg_left < size)
2599			size = (unsigned int)seg_left;
2600	}
2601
2602	return size;
2603}
2604EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
2605
2606int pnfs_write_done_resend_to_mds(struct nfs_pgio_header *hdr)
2607{
2608	struct nfs_pageio_descriptor pgio;
2609
2610	/* Resend all requests through the MDS */
2611	nfs_pageio_init_write(&pgio, hdr->inode, FLUSH_STABLE, true,
2612			      hdr->completion_ops);
2613	set_bit(NFS_CONTEXT_RESEND_WRITES, &hdr->args.context->flags);
2614	return nfs_pageio_resend(&pgio, hdr);
2615}
2616EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
2617
2618static void pnfs_ld_handle_write_error(struct nfs_pgio_header *hdr)
2619{
2620
2621	dprintk("pnfs write error = %d\n", hdr->pnfs_error);
2622	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2623	    PNFS_LAYOUTRET_ON_ERROR) {
2624		pnfs_return_layout(hdr->inode);
2625	}
2626	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2627		hdr->task.tk_status = pnfs_write_done_resend_to_mds(hdr);
2628}
2629
2630/*
2631 * Called by non rpc-based layout drivers
2632 */
2633void pnfs_ld_write_done(struct nfs_pgio_header *hdr)
2634{
2635	if (likely(!hdr->pnfs_error)) {
2636		pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
2637				hdr->mds_offset + hdr->res.count);
2638		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
2639	}
2640	trace_nfs4_pnfs_write(hdr, hdr->pnfs_error);
2641	if (unlikely(hdr->pnfs_error))
2642		pnfs_ld_handle_write_error(hdr);
2643	hdr->mds_ops->rpc_release(hdr);
2644}
2645EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
2646
2647static void
2648pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
2649		struct nfs_pgio_header *hdr)
2650{
2651	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2652
2653	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2654		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
2655		nfs_pageio_reset_write_mds(desc);
2656		mirror->pg_recoalesce = 1;
2657	}
2658	hdr->completion_ops->completion(hdr);
2659}
2660
2661static enum pnfs_try_status
2662pnfs_try_to_write_data(struct nfs_pgio_header *hdr,
2663			const struct rpc_call_ops *call_ops,
2664			struct pnfs_layout_segment *lseg,
2665			int how)
2666{
2667	struct inode *inode = hdr->inode;
2668	enum pnfs_try_status trypnfs;
2669	struct nfs_server *nfss = NFS_SERVER(inode);
2670
2671	hdr->mds_ops = call_ops;
2672
2673	dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
2674		inode->i_ino, hdr->args.count, hdr->args.offset, how);
2675	trypnfs = nfss->pnfs_curr_ld->write_pagelist(hdr, how);
2676	if (trypnfs != PNFS_NOT_ATTEMPTED)
2677		nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
2678	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
2679	return trypnfs;
2680}
2681
2682static void
2683pnfs_do_write(struct nfs_pageio_descriptor *desc,
2684	      struct nfs_pgio_header *hdr, int how)
2685{
2686	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
2687	struct pnfs_layout_segment *lseg = desc->pg_lseg;
2688	enum pnfs_try_status trypnfs;
2689
2690	trypnfs = pnfs_try_to_write_data(hdr, call_ops, lseg, how);
2691	switch (trypnfs) {
2692	case PNFS_NOT_ATTEMPTED:
2693		pnfs_write_through_mds(desc, hdr);
 
2694	case PNFS_ATTEMPTED:
2695		break;
2696	case PNFS_TRY_AGAIN:
2697		/* cleanup hdr and prepare to redo pnfs */
2698		if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2699			struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2700			list_splice_init(&hdr->pages, &mirror->pg_list);
2701			mirror->pg_recoalesce = 1;
2702		}
2703		hdr->mds_ops->rpc_release(hdr);
2704	}
2705}
2706
2707static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
2708{
2709	pnfs_put_lseg(hdr->lseg);
2710	nfs_pgio_header_free(hdr);
2711}
2712
2713int
2714pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
2715{
2716	struct nfs_pgio_header *hdr;
2717	int ret;
2718
2719	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
2720	if (!hdr) {
2721		desc->pg_error = -ENOMEM;
2722		return desc->pg_error;
2723	}
2724	nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
2725
2726	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
2727	ret = nfs_generic_pgio(desc, hdr);
2728	if (!ret)
2729		pnfs_do_write(desc, hdr, desc->pg_ioflags);
2730
2731	return ret;
2732}
2733EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
2734
2735int pnfs_read_done_resend_to_mds(struct nfs_pgio_header *hdr)
2736{
2737	struct nfs_pageio_descriptor pgio;
2738
2739	/* Resend all requests through the MDS */
2740	nfs_pageio_init_read(&pgio, hdr->inode, true, hdr->completion_ops);
2741	return nfs_pageio_resend(&pgio, hdr);
2742}
2743EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
2744
2745static void pnfs_ld_handle_read_error(struct nfs_pgio_header *hdr)
2746{
2747	dprintk("pnfs read error = %d\n", hdr->pnfs_error);
2748	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2749	    PNFS_LAYOUTRET_ON_ERROR) {
2750		pnfs_return_layout(hdr->inode);
2751	}
2752	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2753		hdr->task.tk_status = pnfs_read_done_resend_to_mds(hdr);
2754}
2755
2756/*
2757 * Called by non rpc-based layout drivers
2758 */
2759void pnfs_ld_read_done(struct nfs_pgio_header *hdr)
2760{
2761	if (likely(!hdr->pnfs_error))
2762		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
2763	trace_nfs4_pnfs_read(hdr, hdr->pnfs_error);
2764	if (unlikely(hdr->pnfs_error))
2765		pnfs_ld_handle_read_error(hdr);
2766	hdr->mds_ops->rpc_release(hdr);
2767}
2768EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
2769
2770static void
2771pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
2772		struct nfs_pgio_header *hdr)
2773{
2774	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2775
2776	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2777		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
2778		nfs_pageio_reset_read_mds(desc);
2779		mirror->pg_recoalesce = 1;
2780	}
2781	hdr->completion_ops->completion(hdr);
2782}
2783
2784/*
2785 * Call the appropriate parallel I/O subsystem read function.
2786 */
2787static enum pnfs_try_status
2788pnfs_try_to_read_data(struct nfs_pgio_header *hdr,
2789		       const struct rpc_call_ops *call_ops,
2790		       struct pnfs_layout_segment *lseg)
2791{
2792	struct inode *inode = hdr->inode;
2793	struct nfs_server *nfss = NFS_SERVER(inode);
2794	enum pnfs_try_status trypnfs;
2795
2796	hdr->mds_ops = call_ops;
2797
2798	dprintk("%s: Reading ino:%lu %u@%llu\n",
2799		__func__, inode->i_ino, hdr->args.count, hdr->args.offset);
2800
2801	trypnfs = nfss->pnfs_curr_ld->read_pagelist(hdr);
2802	if (trypnfs != PNFS_NOT_ATTEMPTED)
2803		nfs_inc_stats(inode, NFSIOS_PNFS_READ);
2804	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
2805	return trypnfs;
2806}
2807
2808/* Resend all requests through pnfs. */
2809void pnfs_read_resend_pnfs(struct nfs_pgio_header *hdr)
 
2810{
2811	struct nfs_pageio_descriptor pgio;
2812
2813	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2814		/* Prevent deadlocks with layoutreturn! */
2815		pnfs_put_lseg(hdr->lseg);
2816		hdr->lseg = NULL;
2817
2818		nfs_pageio_init_read(&pgio, hdr->inode, false,
2819					hdr->completion_ops);
 
2820		hdr->task.tk_status = nfs_pageio_resend(&pgio, hdr);
2821	}
2822}
2823EXPORT_SYMBOL_GPL(pnfs_read_resend_pnfs);
2824
2825static void
2826pnfs_do_read(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr)
2827{
2828	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
2829	struct pnfs_layout_segment *lseg = desc->pg_lseg;
2830	enum pnfs_try_status trypnfs;
2831
2832	trypnfs = pnfs_try_to_read_data(hdr, call_ops, lseg);
2833	switch (trypnfs) {
2834	case PNFS_NOT_ATTEMPTED:
2835		pnfs_read_through_mds(desc, hdr);
 
2836	case PNFS_ATTEMPTED:
2837		break;
2838	case PNFS_TRY_AGAIN:
2839		/* cleanup hdr and prepare to redo pnfs */
2840		if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2841			struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2842			list_splice_init(&hdr->pages, &mirror->pg_list);
2843			mirror->pg_recoalesce = 1;
2844		}
2845		hdr->mds_ops->rpc_release(hdr);
2846	}
2847}
2848
2849static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
2850{
2851	pnfs_put_lseg(hdr->lseg);
2852	nfs_pgio_header_free(hdr);
2853}
2854
2855int
2856pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
2857{
2858	struct nfs_pgio_header *hdr;
2859	int ret;
2860
2861	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
2862	if (!hdr) {
2863		desc->pg_error = -ENOMEM;
2864		return desc->pg_error;
2865	}
2866	nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
2867	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
2868	ret = nfs_generic_pgio(desc, hdr);
2869	if (!ret)
2870		pnfs_do_read(desc, hdr);
2871	return ret;
2872}
2873EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
2874
2875static void pnfs_clear_layoutcommitting(struct inode *inode)
2876{
2877	unsigned long *bitlock = &NFS_I(inode)->flags;
2878
2879	clear_bit_unlock(NFS_INO_LAYOUTCOMMITTING, bitlock);
2880	smp_mb__after_atomic();
2881	wake_up_bit(bitlock, NFS_INO_LAYOUTCOMMITTING);
2882}
2883
2884/*
2885 * There can be multiple RW segments.
2886 */
2887static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
2888{
2889	struct pnfs_layout_segment *lseg;
2890
2891	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
2892		if (lseg->pls_range.iomode == IOMODE_RW &&
2893		    test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
2894			list_add(&lseg->pls_lc_list, listp);
2895	}
2896}
2897
2898static void pnfs_list_write_lseg_done(struct inode *inode, struct list_head *listp)
2899{
2900	struct pnfs_layout_segment *lseg, *tmp;
2901
2902	/* Matched by references in pnfs_set_layoutcommit */
2903	list_for_each_entry_safe(lseg, tmp, listp, pls_lc_list) {
2904		list_del_init(&lseg->pls_lc_list);
2905		pnfs_put_lseg(lseg);
2906	}
2907
2908	pnfs_clear_layoutcommitting(inode);
2909}
2910
2911void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
2912{
2913	pnfs_layout_io_set_failed(lseg->pls_layout, lseg->pls_range.iomode);
2914}
2915EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
2916
2917void
2918pnfs_set_layoutcommit(struct inode *inode, struct pnfs_layout_segment *lseg,
2919		loff_t end_pos)
2920{
2921	struct nfs_inode *nfsi = NFS_I(inode);
2922	bool mark_as_dirty = false;
2923
2924	spin_lock(&inode->i_lock);
2925	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
2926		nfsi->layout->plh_lwb = end_pos;
2927		mark_as_dirty = true;
2928		dprintk("%s: Set layoutcommit for inode %lu ",
2929			__func__, inode->i_ino);
2930	} else if (end_pos > nfsi->layout->plh_lwb)
2931		nfsi->layout->plh_lwb = end_pos;
2932	if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags)) {
2933		/* references matched in nfs4_layoutcommit_release */
2934		pnfs_get_lseg(lseg);
2935	}
2936	spin_unlock(&inode->i_lock);
2937	dprintk("%s: lseg %p end_pos %llu\n",
2938		__func__, lseg, nfsi->layout->plh_lwb);
2939
2940	/* if pnfs_layoutcommit_inode() runs between inode locks, the next one
2941	 * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */
2942	if (mark_as_dirty)
2943		mark_inode_dirty_sync(inode);
2944}
2945EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
2946
2947void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data)
2948{
2949	struct nfs_server *nfss = NFS_SERVER(data->args.inode);
2950
2951	if (nfss->pnfs_curr_ld->cleanup_layoutcommit)
2952		nfss->pnfs_curr_ld->cleanup_layoutcommit(data);
2953	pnfs_list_write_lseg_done(data->args.inode, &data->lseg_list);
2954}
2955
2956/*
2957 * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
2958 * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
2959 * data to disk to allow the server to recover the data if it crashes.
2960 * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
2961 * is off, and a COMMIT is sent to a data server, or
2962 * if WRITEs to a data server return NFS_DATA_SYNC.
2963 */
2964int
2965pnfs_layoutcommit_inode(struct inode *inode, bool sync)
2966{
2967	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
2968	struct nfs4_layoutcommit_data *data;
2969	struct nfs_inode *nfsi = NFS_I(inode);
2970	loff_t end_pos;
2971	int status;
2972
2973	if (!pnfs_layoutcommit_outstanding(inode))
2974		return 0;
2975
2976	dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
2977
2978	status = -EAGAIN;
2979	if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
2980		if (!sync)
2981			goto out;
2982		status = wait_on_bit_lock_action(&nfsi->flags,
2983				NFS_INO_LAYOUTCOMMITTING,
2984				nfs_wait_bit_killable,
2985				TASK_KILLABLE);
2986		if (status)
2987			goto out;
2988	}
2989
2990	status = -ENOMEM;
2991	/* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
2992	data = kzalloc(sizeof(*data), GFP_NOFS);
2993	if (!data)
2994		goto clear_layoutcommitting;
2995
2996	status = 0;
2997	spin_lock(&inode->i_lock);
2998	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
2999		goto out_unlock;
3000
3001	INIT_LIST_HEAD(&data->lseg_list);
3002	pnfs_list_write_lseg(inode, &data->lseg_list);
3003
3004	end_pos = nfsi->layout->plh_lwb;
3005
3006	nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
 
3007	spin_unlock(&inode->i_lock);
3008
3009	data->args.inode = inode;
3010	data->cred = get_cred(nfsi->layout->plh_lc_cred);
3011	nfs_fattr_init(&data->fattr);
3012	data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
3013	data->res.fattr = &data->fattr;
3014	if (end_pos != 0)
3015		data->args.lastbytewritten = end_pos - 1;
3016	else
3017		data->args.lastbytewritten = U64_MAX;
3018	data->res.server = NFS_SERVER(inode);
3019
3020	if (ld->prepare_layoutcommit) {
3021		status = ld->prepare_layoutcommit(&data->args);
3022		if (status) {
3023			put_cred(data->cred);
3024			spin_lock(&inode->i_lock);
3025			set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags);
3026			if (end_pos > nfsi->layout->plh_lwb)
3027				nfsi->layout->plh_lwb = end_pos;
3028			goto out_unlock;
3029		}
3030	}
3031
3032
3033	status = nfs4_proc_layoutcommit(data, sync);
3034out:
3035	if (status)
3036		mark_inode_dirty_sync(inode);
3037	dprintk("<-- %s status %d\n", __func__, status);
3038	return status;
3039out_unlock:
3040	spin_unlock(&inode->i_lock);
3041	kfree(data);
3042clear_layoutcommitting:
3043	pnfs_clear_layoutcommitting(inode);
3044	goto out;
3045}
3046EXPORT_SYMBOL_GPL(pnfs_layoutcommit_inode);
3047
3048int
3049pnfs_generic_sync(struct inode *inode, bool datasync)
3050{
3051	return pnfs_layoutcommit_inode(inode, true);
3052}
3053EXPORT_SYMBOL_GPL(pnfs_generic_sync);
3054
3055struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
3056{
3057	struct nfs4_threshold *thp;
3058
3059	thp = kzalloc(sizeof(*thp), GFP_NOFS);
3060	if (!thp) {
3061		dprintk("%s mdsthreshold allocation failed\n", __func__);
3062		return NULL;
3063	}
3064	return thp;
3065}
3066
3067#if IS_ENABLED(CONFIG_NFS_V4_2)
3068int
3069pnfs_report_layoutstat(struct inode *inode, gfp_t gfp_flags)
3070{
3071	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
3072	struct nfs_server *server = NFS_SERVER(inode);
3073	struct nfs_inode *nfsi = NFS_I(inode);
3074	struct nfs42_layoutstat_data *data;
3075	struct pnfs_layout_hdr *hdr;
3076	int status = 0;
3077
3078	if (!pnfs_enabled_sb(server) || !ld->prepare_layoutstats)
3079		goto out;
3080
3081	if (!nfs_server_capable(inode, NFS_CAP_LAYOUTSTATS))
3082		goto out;
3083
3084	if (test_and_set_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags))
3085		goto out;
3086
3087	spin_lock(&inode->i_lock);
3088	if (!NFS_I(inode)->layout) {
3089		spin_unlock(&inode->i_lock);
3090		goto out_clear_layoutstats;
3091	}
3092	hdr = NFS_I(inode)->layout;
3093	pnfs_get_layout_hdr(hdr);
3094	spin_unlock(&inode->i_lock);
3095
3096	data = kzalloc(sizeof(*data), gfp_flags);
3097	if (!data) {
3098		status = -ENOMEM;
3099		goto out_put;
3100	}
3101
3102	data->args.fh = NFS_FH(inode);
3103	data->args.inode = inode;
3104	status = ld->prepare_layoutstats(&data->args);
3105	if (status)
3106		goto out_free;
3107
3108	status = nfs42_proc_layoutstats_generic(NFS_SERVER(inode), data);
3109
3110out:
3111	dprintk("%s returns %d\n", __func__, status);
3112	return status;
3113
3114out_free:
3115	kfree(data);
3116out_put:
3117	pnfs_put_layout_hdr(hdr);
3118out_clear_layoutstats:
3119	smp_mb__before_atomic();
3120	clear_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags);
3121	smp_mb__after_atomic();
3122	goto out;
3123}
3124EXPORT_SYMBOL_GPL(pnfs_report_layoutstat);
3125#endif
3126
3127unsigned int layoutstats_timer;
3128module_param(layoutstats_timer, uint, 0644);
3129EXPORT_SYMBOL_GPL(layoutstats_timer);