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v6.13.7
   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);
  64static int pnfs_layout_return_on_reboot(struct pnfs_layout_hdr *lo);
  65
  66/* Return the registered pnfs layout driver module matching given id */
  67static struct pnfs_layoutdriver_type *
  68find_pnfs_driver_locked(u32 id)
  69{
  70	struct pnfs_layoutdriver_type *local;
  71
  72	list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid)
  73		if (local->id == id)
  74			goto out;
  75	local = NULL;
  76out:
  77	dprintk("%s: Searching for id %u, found %p\n", __func__, id, local);
  78	return local;
  79}
  80
  81static struct pnfs_layoutdriver_type *
  82find_pnfs_driver(u32 id)
  83{
  84	struct pnfs_layoutdriver_type *local;
  85
  86	spin_lock(&pnfs_spinlock);
  87	local = find_pnfs_driver_locked(id);
  88	if (local != NULL && !try_module_get(local->owner)) {
  89		dprintk("%s: Could not grab reference on module\n", __func__);
  90		local = NULL;
  91	}
  92	spin_unlock(&pnfs_spinlock);
  93	return local;
  94}
  95
  96const struct pnfs_layoutdriver_type *pnfs_find_layoutdriver(u32 id)
  97{
  98	return find_pnfs_driver(id);
  99}
 100
 101void pnfs_put_layoutdriver(const struct pnfs_layoutdriver_type *ld)
 102{
 103	if (ld)
 104		module_put(ld->owner);
 105}
 106
 107void
 108unset_pnfs_layoutdriver(struct nfs_server *nfss)
 109{
 110	if (nfss->pnfs_curr_ld) {
 111		if (nfss->pnfs_curr_ld->clear_layoutdriver)
 112			nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
 113		/* Decrement the MDS count. Purge the deviceid cache if zero */
 114		if (atomic_dec_and_test(&nfss->nfs_client->cl_mds_count))
 115			nfs4_deviceid_purge_client(nfss->nfs_client);
 116		module_put(nfss->pnfs_curr_ld->owner);
 117	}
 118	nfss->pnfs_curr_ld = NULL;
 119}
 120
 121/*
 122 * When the server sends a list of layout types, we choose one in the order
 123 * given in the list below.
 124 *
 125 * FIXME: should this list be configurable in some fashion? module param?
 126 * 	  mount option? something else?
 127 */
 128static const u32 ld_prefs[] = {
 129	LAYOUT_SCSI,
 130	LAYOUT_BLOCK_VOLUME,
 131	LAYOUT_OSD2_OBJECTS,
 132	LAYOUT_FLEX_FILES,
 133	LAYOUT_NFSV4_1_FILES,
 134	0
 135};
 136
 137static int
 138ld_cmp(const void *e1, const void *e2)
 139{
 140	u32 ld1 = *((u32 *)e1);
 141	u32 ld2 = *((u32 *)e2);
 142	int i;
 143
 144	for (i = 0; ld_prefs[i] != 0; i++) {
 145		if (ld1 == ld_prefs[i])
 146			return -1;
 147
 148		if (ld2 == ld_prefs[i])
 149			return 1;
 150	}
 151	return 0;
 152}
 153
 154/*
 155 * Try to set the server's pnfs module to the pnfs layout type specified by id.
 156 * Currently only one pNFS layout driver per filesystem is supported.
 157 *
 158 * @ids array of layout types supported by MDS.
 159 */
 160void
 161set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
 162		      struct nfs_fsinfo *fsinfo)
 163{
 164	struct pnfs_layoutdriver_type *ld_type = NULL;
 165	u32 id;
 166	int i;
 167
 168	if (fsinfo->nlayouttypes == 0)
 169		goto out_no_driver;
 170	if (!(server->nfs_client->cl_exchange_flags &
 171		 (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
 172		printk(KERN_ERR "NFS: %s: cl_exchange_flags 0x%x\n",
 173			__func__, server->nfs_client->cl_exchange_flags);
 174		goto out_no_driver;
 175	}
 176
 177	sort(fsinfo->layouttype, fsinfo->nlayouttypes,
 178		sizeof(*fsinfo->layouttype), ld_cmp, NULL);
 179
 180	for (i = 0; i < fsinfo->nlayouttypes; i++) {
 181		id = fsinfo->layouttype[i];
 182		ld_type = find_pnfs_driver(id);
 183		if (!ld_type) {
 184			request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX,
 185					id);
 186			ld_type = find_pnfs_driver(id);
 187		}
 188		if (ld_type)
 189			break;
 190	}
 191
 192	if (!ld_type) {
 193		dprintk("%s: No pNFS module found!\n", __func__);
 194		goto out_no_driver;
 195	}
 196
 197	server->pnfs_curr_ld = ld_type;
 198	if (ld_type->set_layoutdriver
 199	    && ld_type->set_layoutdriver(server, mntfh)) {
 200		printk(KERN_ERR "NFS: %s: Error initializing pNFS layout "
 201			"driver %u.\n", __func__, id);
 202		module_put(ld_type->owner);
 203		goto out_no_driver;
 204	}
 205	/* Bump the MDS count */
 206	atomic_inc(&server->nfs_client->cl_mds_count);
 207
 208	dprintk("%s: pNFS module for %u set\n", __func__, id);
 209	return;
 210
 211out_no_driver:
 212	dprintk("%s: Using NFSv4 I/O\n", __func__);
 213	server->pnfs_curr_ld = NULL;
 214}
 215
 216int
 217pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 218{
 219	int status = -EINVAL;
 220	struct pnfs_layoutdriver_type *tmp;
 221
 222	if (ld_type->id == 0) {
 223		printk(KERN_ERR "NFS: %s id 0 is reserved\n", __func__);
 224		return status;
 225	}
 226	if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
 227		printk(KERN_ERR "NFS: %s Layout driver must provide "
 228		       "alloc_lseg and free_lseg.\n", __func__);
 229		return status;
 230	}
 231
 232	spin_lock(&pnfs_spinlock);
 233	tmp = find_pnfs_driver_locked(ld_type->id);
 234	if (!tmp) {
 235		list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
 236		status = 0;
 237		dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
 238			ld_type->name);
 239	} else {
 240		printk(KERN_ERR "NFS: %s Module with id %d already loaded!\n",
 241			__func__, ld_type->id);
 242	}
 243	spin_unlock(&pnfs_spinlock);
 244
 245	return status;
 246}
 247EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);
 248
 249void
 250pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 251{
 252	dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
 253	spin_lock(&pnfs_spinlock);
 254	list_del(&ld_type->pnfs_tblid);
 255	spin_unlock(&pnfs_spinlock);
 256}
 257EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
 258
 259/*
 260 * pNFS client layout cache
 261 */
 262
 263/* Need to hold i_lock if caller does not already hold reference */
 264void
 265pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo)
 266{
 267	refcount_inc(&lo->plh_refcount);
 268}
 269
 270static struct pnfs_layout_hdr *
 271pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags)
 272{
 273	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
 274	return ld->alloc_layout_hdr(ino, gfp_flags);
 275}
 276
 277static void
 278pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
 279{
 280	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
 281	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
 282
 283	if (test_and_clear_bit(NFS_LAYOUT_HASHED, &lo->plh_flags)) {
 284		struct nfs_client *clp = server->nfs_client;
 285
 286		spin_lock(&clp->cl_lock);
 287		list_del_rcu(&lo->plh_layouts);
 288		spin_unlock(&clp->cl_lock);
 289	}
 290	put_cred(lo->plh_lc_cred);
 291	return ld->free_layout_hdr(lo);
 292}
 293
 294static void
 295pnfs_detach_layout_hdr(struct pnfs_layout_hdr *lo)
 296{
 297	struct nfs_inode *nfsi = NFS_I(lo->plh_inode);
 298	dprintk("%s: freeing layout cache %p\n", __func__, lo);
 299	nfsi->layout = NULL;
 300	/* Reset MDS Threshold I/O counters */
 301	nfsi->write_io = 0;
 302	nfsi->read_io = 0;
 303}
 304
 305void
 306pnfs_put_layout_hdr(struct pnfs_layout_hdr *lo)
 307{
 308	struct inode *inode;
 309	unsigned long i_state;
 310
 311	if (!lo)
 312		return;
 313	inode = lo->plh_inode;
 314	pnfs_layoutreturn_before_put_layout_hdr(lo);
 315
 316	if (refcount_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
 317		if (!list_empty(&lo->plh_segs))
 318			WARN_ONCE(1, "NFS: BUG unfreed layout segments.\n");
 319		pnfs_detach_layout_hdr(lo);
 320		i_state = inode->i_state;
 321		spin_unlock(&inode->i_lock);
 322		pnfs_free_layout_hdr(lo);
 323		/* Notify pnfs_destroy_layout_final() that we're done */
 324		if (i_state & (I_FREEING | I_CLEAR))
 325			wake_up_var(lo);
 326	}
 327}
 328
 329static struct inode *
 330pnfs_grab_inode_layout_hdr(struct pnfs_layout_hdr *lo)
 331{
 332	struct inode *inode = igrab(lo->plh_inode);
 333	if (inode)
 334		return inode;
 335	set_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags);
 336	return NULL;
 337}
 338
 339/*
 340 * Compare 2 layout stateid sequence ids, to see which is newer,
 341 * taking into account wraparound issues.
 342 */
 343static bool pnfs_seqid_is_newer(u32 s1, u32 s2)
 344{
 345	return (s32)(s1 - s2) > 0;
 346}
 347
 348static void pnfs_barrier_update(struct pnfs_layout_hdr *lo, u32 newseq)
 349{
 350	if (pnfs_seqid_is_newer(newseq, lo->plh_barrier) || !lo->plh_barrier)
 351		lo->plh_barrier = newseq;
 352}
 353
 354static void
 355pnfs_set_plh_return_info(struct pnfs_layout_hdr *lo, enum pnfs_iomode iomode,
 356			 u32 seq)
 357{
 358	if (lo->plh_return_iomode != 0 && lo->plh_return_iomode != iomode)
 359		iomode = IOMODE_ANY;
 360	lo->plh_return_iomode = iomode;
 361	set_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 362	/*
 363	 * We must set lo->plh_return_seq to avoid livelocks with
 364	 * pnfs_layout_need_return()
 365	 */
 366	if (seq == 0)
 367		seq = be32_to_cpu(lo->plh_stateid.seqid);
 368	if (!lo->plh_return_seq || pnfs_seqid_is_newer(seq, lo->plh_return_seq))
 369		lo->plh_return_seq = seq;
 370	pnfs_barrier_update(lo, seq);
 371}
 372
 373static void
 374pnfs_clear_layoutreturn_info(struct pnfs_layout_hdr *lo)
 375{
 376	struct pnfs_layout_segment *lseg;
 377	lo->plh_return_iomode = 0;
 378	lo->plh_return_seq = 0;
 379	clear_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 380	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
 381		if (!test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
 382			continue;
 383		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
 384	}
 385}
 386
 387static void pnfs_clear_layoutreturn_waitbit(struct pnfs_layout_hdr *lo)
 388{
 389	clear_bit_unlock(NFS_LAYOUT_RETURN, &lo->plh_flags);
 390	clear_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags);
 391	smp_mb__after_atomic();
 392	wake_up_bit(&lo->plh_flags, NFS_LAYOUT_RETURN);
 393	rpc_wake_up(&NFS_SERVER(lo->plh_inode)->roc_rpcwaitq);
 394}
 395
 396static void
 397pnfs_clear_lseg_state(struct pnfs_layout_segment *lseg,
 398		struct list_head *free_me)
 399{
 400	clear_bit(NFS_LSEG_ROC, &lseg->pls_flags);
 401	clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
 402	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags))
 403		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 404	if (test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
 405		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 406}
 407
 408/*
 409 * Update the seqid of a layout stateid after receiving
 410 * NFS4ERR_OLD_STATEID
 411 */
 412bool nfs4_layout_refresh_old_stateid(nfs4_stateid *dst,
 413		struct pnfs_layout_range *dst_range,
 414		struct inode *inode)
 415{
 416	struct pnfs_layout_hdr *lo;
 417	struct pnfs_layout_range range = {
 418		.iomode = IOMODE_ANY,
 419		.offset = 0,
 420		.length = NFS4_MAX_UINT64,
 421	};
 422	bool ret = false;
 423	LIST_HEAD(head);
 424	int err;
 425
 426	spin_lock(&inode->i_lock);
 427	lo = NFS_I(inode)->layout;
 428	if (lo &&  pnfs_layout_is_valid(lo) &&
 429	    nfs4_stateid_match_other(dst, &lo->plh_stateid)) {
 430		/* Is our call using the most recent seqid? If so, bump it */
 431		if (!nfs4_stateid_is_newer(&lo->plh_stateid, dst)) {
 432			nfs4_stateid_seqid_inc(dst);
 433			ret = true;
 434			goto out;
 435		}
 436		/* Try to update the seqid to the most recent */
 437		err = pnfs_mark_matching_lsegs_return(lo, &head, &range, 0);
 438		if (err != -EBUSY) {
 439			dst->seqid = lo->plh_stateid.seqid;
 440			*dst_range = range;
 441			ret = true;
 442		}
 443	}
 444out:
 445	spin_unlock(&inode->i_lock);
 446	pnfs_free_lseg_list(&head);
 447	return ret;
 448}
 449
 450/*
 451 * Mark a pnfs_layout_hdr and all associated layout segments as invalid
 452 *
 453 * In order to continue using the pnfs_layout_hdr, a full recovery
 454 * is required.
 455 * Note that caller must hold inode->i_lock.
 456 */
 457int
 458pnfs_mark_layout_stateid_invalid(struct pnfs_layout_hdr *lo,
 459		struct list_head *lseg_list)
 460{
 461	struct pnfs_layout_range range = {
 462		.iomode = IOMODE_ANY,
 463		.offset = 0,
 464		.length = NFS4_MAX_UINT64,
 465	};
 466	struct pnfs_layout_segment *lseg, *next;
 467
 468	set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 469	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 470		pnfs_clear_lseg_state(lseg, lseg_list);
 471	pnfs_clear_layoutreturn_info(lo);
 472	pnfs_free_returned_lsegs(lo, lseg_list, &range, 0);
 473	set_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags);
 474	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags) &&
 475	    !test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
 476		pnfs_clear_layoutreturn_waitbit(lo);
 477	return !list_empty(&lo->plh_segs);
 478}
 479
 480static int pnfs_mark_layout_stateid_return(struct pnfs_layout_hdr *lo,
 481					   struct list_head *lseg_list,
 482					   enum pnfs_iomode iomode, u32 seq)
 483{
 484	struct pnfs_layout_range range = {
 485		.iomode = iomode,
 486		.length = NFS4_MAX_UINT64,
 487	};
 488
 489	return pnfs_mark_matching_lsegs_return(lo, lseg_list, &range, seq);
 490}
 491
 492static int
 493pnfs_iomode_to_fail_bit(u32 iomode)
 494{
 495	return iomode == IOMODE_RW ?
 496		NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 497}
 498
 499static void
 500pnfs_layout_set_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 501{
 502	lo->plh_retry_timestamp = jiffies;
 503	if (!test_and_set_bit(fail_bit, &lo->plh_flags))
 504		refcount_inc(&lo->plh_refcount);
 505}
 506
 507static void
 508pnfs_layout_clear_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 509{
 510	if (test_and_clear_bit(fail_bit, &lo->plh_flags))
 511		refcount_dec(&lo->plh_refcount);
 512}
 513
 514static void
 515pnfs_layout_io_set_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 516{
 517	struct inode *inode = lo->plh_inode;
 518	struct pnfs_layout_range range = {
 519		.iomode = iomode,
 520		.offset = 0,
 521		.length = NFS4_MAX_UINT64,
 522	};
 523	LIST_HEAD(head);
 524
 525	spin_lock(&inode->i_lock);
 526	pnfs_layout_set_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
 527	pnfs_mark_matching_lsegs_return(lo, &head, &range, 0);
 528	spin_unlock(&inode->i_lock);
 529	pnfs_free_lseg_list(&head);
 530	dprintk("%s Setting layout IOMODE_%s fail bit\n", __func__,
 531			iomode == IOMODE_RW ?  "RW" : "READ");
 532}
 533
 534static bool
 535pnfs_layout_io_test_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 536{
 537	unsigned long start, end;
 538	int fail_bit = pnfs_iomode_to_fail_bit(iomode);
 539
 540	if (test_bit(fail_bit, &lo->plh_flags) == 0)
 541		return false;
 542	end = jiffies;
 543	start = end - PNFS_LAYOUTGET_RETRY_TIMEOUT;
 544	if (!time_in_range(lo->plh_retry_timestamp, start, end)) {
 545		/* It is time to retry the failed layoutgets */
 546		pnfs_layout_clear_fail_bit(lo, fail_bit);
 547		return false;
 548	}
 549	return true;
 550}
 551
 552static void
 553pnfs_init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg,
 554		const struct pnfs_layout_range *range,
 555		const nfs4_stateid *stateid)
 556{
 557	INIT_LIST_HEAD(&lseg->pls_list);
 558	INIT_LIST_HEAD(&lseg->pls_lc_list);
 559	INIT_LIST_HEAD(&lseg->pls_commits);
 560	refcount_set(&lseg->pls_refcount, 1);
 561	set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
 562	lseg->pls_layout = lo;
 563	lseg->pls_range = *range;
 564	lseg->pls_seq = be32_to_cpu(stateid->seqid);
 565}
 566
 567static void pnfs_free_lseg(struct pnfs_layout_segment *lseg)
 568{
 569	if (lseg != NULL) {
 570		struct inode *inode = lseg->pls_layout->plh_inode;
 571		NFS_SERVER(inode)->pnfs_curr_ld->free_lseg(lseg);
 572	}
 573}
 574
 575static void
 576pnfs_layout_remove_lseg(struct pnfs_layout_hdr *lo,
 577		struct pnfs_layout_segment *lseg)
 578{
 579	WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 580	list_del_init(&lseg->pls_list);
 581	/* Matched by pnfs_get_layout_hdr in pnfs_layout_insert_lseg */
 582	refcount_dec(&lo->plh_refcount);
 583	if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
 584		return;
 585	if (list_empty(&lo->plh_segs) &&
 586	    !test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) &&
 587	    !test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
 588		if (atomic_read(&lo->plh_outstanding) == 0)
 589			set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 590		clear_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 591	}
 592}
 593
 594static bool
 595pnfs_cache_lseg_for_layoutreturn(struct pnfs_layout_hdr *lo,
 596		struct pnfs_layout_segment *lseg)
 597{
 598	if (test_and_clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags) &&
 599	    pnfs_layout_is_valid(lo)) {
 600		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
 601		list_move_tail(&lseg->pls_list, &lo->plh_return_segs);
 602		return true;
 603	}
 604	return false;
 605}
 606
 607void
 608pnfs_put_lseg(struct pnfs_layout_segment *lseg)
 609{
 610	struct pnfs_layout_hdr *lo;
 611	struct inode *inode;
 612
 613	if (!lseg)
 614		return;
 615
 616	dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
 617		refcount_read(&lseg->pls_refcount),
 618		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 619
 620	lo = lseg->pls_layout;
 621	inode = lo->plh_inode;
 622
 623	if (refcount_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
 
 
 
 
 624		pnfs_get_layout_hdr(lo);
 625		pnfs_layout_remove_lseg(lo, lseg);
 626		if (pnfs_cache_lseg_for_layoutreturn(lo, lseg))
 627			lseg = NULL;
 628		spin_unlock(&inode->i_lock);
 629		pnfs_free_lseg(lseg);
 630		pnfs_put_layout_hdr(lo);
 631	}
 632}
 633EXPORT_SYMBOL_GPL(pnfs_put_lseg);
 634
 635/*
 636 * is l2 fully contained in l1?
 637 *   start1                             end1
 638 *   [----------------------------------)
 639 *           start2           end2
 640 *           [----------------)
 641 */
 642static bool
 643pnfs_lseg_range_contained(const struct pnfs_layout_range *l1,
 644		 const struct pnfs_layout_range *l2)
 645{
 646	u64 start1 = l1->offset;
 647	u64 end1 = pnfs_end_offset(start1, l1->length);
 648	u64 start2 = l2->offset;
 649	u64 end2 = pnfs_end_offset(start2, l2->length);
 650
 651	return (start1 <= start2) && (end1 >= end2);
 652}
 653
 654static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
 655		struct list_head *tmp_list)
 656{
 657	if (!refcount_dec_and_test(&lseg->pls_refcount))
 658		return false;
 659	pnfs_layout_remove_lseg(lseg->pls_layout, lseg);
 660	list_add(&lseg->pls_list, tmp_list);
 661	return true;
 662}
 663
 664/* Returns 1 if lseg is removed from list, 0 otherwise */
 665static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
 666			     struct list_head *tmp_list)
 667{
 668	int rv = 0;
 669
 670	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 671		/* Remove the reference keeping the lseg in the
 672		 * list.  It will now be removed when all
 673		 * outstanding io is finished.
 674		 */
 675		dprintk("%s: lseg %p ref %d\n", __func__, lseg,
 676			refcount_read(&lseg->pls_refcount));
 677		if (pnfs_lseg_dec_and_remove_zero(lseg, tmp_list))
 678			rv = 1;
 679	}
 680	return rv;
 681}
 682
 683static bool
 684pnfs_should_free_range(const struct pnfs_layout_range *lseg_range,
 685		 const struct pnfs_layout_range *recall_range)
 686{
 687	return (recall_range->iomode == IOMODE_ANY ||
 688		lseg_range->iomode == recall_range->iomode) &&
 689	       pnfs_lseg_range_intersecting(lseg_range, recall_range);
 690}
 691
 692static bool
 693pnfs_match_lseg_recall(const struct pnfs_layout_segment *lseg,
 694		const struct pnfs_layout_range *recall_range,
 695		u32 seq)
 696{
 697	if (seq != 0 && pnfs_seqid_is_newer(lseg->pls_seq, seq))
 698		return false;
 699	if (recall_range == NULL)
 700		return true;
 701	return pnfs_should_free_range(&lseg->pls_range, recall_range);
 702}
 703
 704/**
 705 * pnfs_mark_matching_lsegs_invalid - tear down lsegs or mark them for later
 706 * @lo: layout header containing the lsegs
 707 * @tmp_list: list head where doomed lsegs should go
 708 * @recall_range: optional recall range argument to match (may be NULL)
 709 * @seq: only invalidate lsegs obtained prior to this sequence (may be 0)
 710 *
 711 * Walk the list of lsegs in the layout header, and tear down any that should
 712 * be destroyed. If "recall_range" is specified then the segment must match
 713 * that range. If "seq" is non-zero, then only match segments that were handed
 714 * out at or before that sequence.
 715 *
 716 * Returns number of matching invalid lsegs remaining in list after scanning
 717 * it and purging them.
 718 */
 719int
 720pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 721			    struct list_head *tmp_list,
 722			    const struct pnfs_layout_range *recall_range,
 723			    u32 seq)
 724{
 725	struct pnfs_layout_segment *lseg, *next;
 726	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
 727	int remaining = 0;
 728
 729	dprintk("%s:Begin lo %p\n", __func__, lo);
 730
 731	if (list_empty(&lo->plh_segs))
 732		return 0;
 733	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 734		if (pnfs_match_lseg_recall(lseg, recall_range, seq)) {
 735			dprintk("%s: freeing lseg %p iomode %d seq %u "
 736				"offset %llu length %llu\n", __func__,
 737				lseg, lseg->pls_range.iomode, lseg->pls_seq,
 738				lseg->pls_range.offset, lseg->pls_range.length);
 739			if (mark_lseg_invalid(lseg, tmp_list))
 740				continue;
 741			remaining++;
 742			pnfs_lseg_cancel_io(server, lseg);
 743		}
 744	dprintk("%s:Return %i\n", __func__, remaining);
 745	return remaining;
 746}
 747
 748static void
 749pnfs_free_returned_lsegs(struct pnfs_layout_hdr *lo,
 750		struct list_head *free_me,
 751		const struct pnfs_layout_range *range,
 752		u32 seq)
 753{
 754	struct pnfs_layout_segment *lseg, *next;
 755
 756	list_for_each_entry_safe(lseg, next, &lo->plh_return_segs, pls_list) {
 757		if (pnfs_match_lseg_recall(lseg, range, seq))
 758			list_move_tail(&lseg->pls_list, free_me);
 759	}
 760}
 761
 762/* note free_me must contain lsegs from a single layout_hdr */
 763void
 764pnfs_free_lseg_list(struct list_head *free_me)
 765{
 766	struct pnfs_layout_segment *lseg, *tmp;
 767
 768	if (list_empty(free_me))
 769		return;
 770
 771	list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
 772		list_del(&lseg->pls_list);
 773		pnfs_free_lseg(lseg);
 774	}
 775}
 776
 777static struct pnfs_layout_hdr *__pnfs_destroy_layout(struct nfs_inode *nfsi)
 778{
 779	struct pnfs_layout_hdr *lo;
 780	LIST_HEAD(tmp_list);
 781
 782	spin_lock(&nfsi->vfs_inode.i_lock);
 783	lo = nfsi->layout;
 784	if (lo) {
 785		pnfs_get_layout_hdr(lo);
 786		pnfs_mark_layout_stateid_invalid(lo, &tmp_list);
 787		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RO_FAILED);
 788		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RW_FAILED);
 789		spin_unlock(&nfsi->vfs_inode.i_lock);
 790		pnfs_free_lseg_list(&tmp_list);
 791		nfs_commit_inode(&nfsi->vfs_inode, 0);
 792		pnfs_put_layout_hdr(lo);
 793	} else
 794		spin_unlock(&nfsi->vfs_inode.i_lock);
 795	return lo;
 796}
 797
 798void pnfs_destroy_layout(struct nfs_inode *nfsi)
 799{
 800	__pnfs_destroy_layout(nfsi);
 801}
 802EXPORT_SYMBOL_GPL(pnfs_destroy_layout);
 803
 804static bool pnfs_layout_removed(struct nfs_inode *nfsi,
 805				struct pnfs_layout_hdr *lo)
 806{
 807	bool ret;
 808
 809	spin_lock(&nfsi->vfs_inode.i_lock);
 810	ret = nfsi->layout != lo;
 811	spin_unlock(&nfsi->vfs_inode.i_lock);
 812	return ret;
 813}
 814
 815void pnfs_destroy_layout_final(struct nfs_inode *nfsi)
 816{
 817	struct pnfs_layout_hdr *lo = __pnfs_destroy_layout(nfsi);
 818
 819	if (lo)
 820		wait_var_event(lo, pnfs_layout_removed(nfsi, lo));
 821}
 822
 823static bool
 824pnfs_layout_add_bulk_destroy_list(struct inode *inode,
 825		struct list_head *layout_list)
 826{
 827	struct pnfs_layout_hdr *lo;
 828	bool ret = false;
 829
 830	spin_lock(&inode->i_lock);
 831	lo = NFS_I(inode)->layout;
 832	if (lo != NULL && list_empty(&lo->plh_bulk_destroy)) {
 833		pnfs_get_layout_hdr(lo);
 834		list_add(&lo->plh_bulk_destroy, layout_list);
 835		ret = true;
 836	}
 837	spin_unlock(&inode->i_lock);
 838	return ret;
 839}
 840
 841/* Caller must hold rcu_read_lock and clp->cl_lock */
 842static int
 843pnfs_layout_bulk_destroy_byserver_locked(struct nfs_client *clp,
 844		struct nfs_server *server,
 845		struct list_head *layout_list)
 846	__must_hold(&clp->cl_lock)
 847	__must_hold(RCU)
 848{
 849	struct pnfs_layout_hdr *lo, *next;
 850	struct inode *inode;
 851
 852	list_for_each_entry_safe(lo, next, &server->layouts, plh_layouts) {
 853		if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags) ||
 854		    test_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags) ||
 855		    !list_empty(&lo->plh_bulk_destroy))
 856			continue;
 857		/* If the sb is being destroyed, just bail */
 858		if (!nfs_sb_active(server->super))
 859			break;
 860		inode = pnfs_grab_inode_layout_hdr(lo);
 861		if (inode != NULL) {
 
 
 862			if (pnfs_layout_add_bulk_destroy_list(inode,
 863						layout_list))
 864				continue;
 865			rcu_read_unlock();
 866			spin_unlock(&clp->cl_lock);
 867			iput(inode);
 868		} else {
 869			rcu_read_unlock();
 870			spin_unlock(&clp->cl_lock);
 871		}
 872		nfs_sb_deactive(server->super);
 873		spin_lock(&clp->cl_lock);
 874		rcu_read_lock();
 875		return -EAGAIN;
 876	}
 877	return 0;
 878}
 879
 880static int
 881pnfs_layout_free_bulk_destroy_list(struct list_head *layout_list,
 882				   enum pnfs_layout_destroy_mode mode)
 883{
 884	struct pnfs_layout_hdr *lo;
 885	struct inode *inode;
 886	LIST_HEAD(lseg_list);
 887	int ret = 0;
 888
 889	while (!list_empty(layout_list)) {
 890		lo = list_entry(layout_list->next, struct pnfs_layout_hdr,
 891				plh_bulk_destroy);
 892		dprintk("%s freeing layout for inode %lu\n", __func__,
 893			lo->plh_inode->i_ino);
 894		inode = lo->plh_inode;
 895
 896		pnfs_layoutcommit_inode(inode, false);
 897
 898		spin_lock(&inode->i_lock);
 899		list_del_init(&lo->plh_bulk_destroy);
 900		if (mode == PNFS_LAYOUT_FILE_BULK_RETURN) {
 901			pnfs_mark_layout_stateid_return(lo, &lseg_list,
 902							IOMODE_ANY, 0);
 903		} else if (pnfs_mark_layout_stateid_invalid(lo, &lseg_list)) {
 904			if (mode == PNFS_LAYOUT_BULK_RETURN)
 905				set_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 906			ret = -EAGAIN;
 907		}
 908		spin_unlock(&inode->i_lock);
 909		pnfs_free_lseg_list(&lseg_list);
 910		/* Free all lsegs that are attached to commit buckets */
 911		nfs_commit_inode(inode, 0);
 912		pnfs_put_layout_hdr(lo);
 913		nfs_iput_and_deactive(inode);
 914	}
 915	return ret;
 916}
 917
 918int pnfs_layout_destroy_byfsid(struct nfs_client *clp, struct nfs_fsid *fsid,
 919			       enum pnfs_layout_destroy_mode mode)
 
 
 920{
 921	struct nfs_server *server;
 922	LIST_HEAD(layout_list);
 923
 924	spin_lock(&clp->cl_lock);
 925	rcu_read_lock();
 926restart:
 927	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 928		if (memcmp(&server->fsid, fsid, sizeof(*fsid)) != 0)
 929			continue;
 930		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 931				server,
 932				&layout_list) != 0)
 933			goto restart;
 934	}
 935	rcu_read_unlock();
 936	spin_unlock(&clp->cl_lock);
 937
 938	return pnfs_layout_free_bulk_destroy_list(&layout_list, mode);
 
 
 939}
 940
 941static void pnfs_layout_build_destroy_list_byclient(struct nfs_client *clp,
 942						    struct list_head *list)
 
 943{
 944	struct nfs_server *server;
 
 945
 946	spin_lock(&clp->cl_lock);
 947	rcu_read_lock();
 948restart:
 949	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 950		if (pnfs_layout_bulk_destroy_byserver_locked(clp, server,
 951							     list) != 0)
 
 952			goto restart;
 953	}
 954	rcu_read_unlock();
 955	spin_unlock(&clp->cl_lock);
 956}
 957
 958static int pnfs_layout_do_destroy_byclid(struct nfs_client *clp,
 959					 struct list_head *list,
 960					 enum pnfs_layout_destroy_mode mode)
 961{
 962	pnfs_layout_build_destroy_list_byclient(clp, list);
 963	return pnfs_layout_free_bulk_destroy_list(list, mode);
 964}
 965
 966int pnfs_layout_destroy_byclid(struct nfs_client *clp,
 967			       enum pnfs_layout_destroy_mode mode)
 968{
 969	LIST_HEAD(layout_list);
 970
 971	return pnfs_layout_do_destroy_byclid(clp, &layout_list, mode);
 972}
 973
 974/*
 975 * Called by the state manager to remove all layouts established under an
 976 * expired lease.
 977 */
 978void
 979pnfs_destroy_all_layouts(struct nfs_client *clp)
 980{
 981	nfs4_deviceid_mark_client_invalid(clp);
 982	nfs4_deviceid_purge_client(clp);
 983
 984	pnfs_layout_destroy_byclid(clp, PNFS_LAYOUT_INVALIDATE);
 985}
 986
 987static void pnfs_layout_build_recover_list_byclient(struct nfs_client *clp,
 988						    struct list_head *list)
 989{
 990	struct nfs_server *server;
 991
 992	spin_lock(&clp->cl_lock);
 993	rcu_read_lock();
 994restart:
 995	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 996		if (!(server->caps & NFS_CAP_REBOOT_LAYOUTRETURN))
 997			continue;
 998		if (pnfs_layout_bulk_destroy_byserver_locked(clp, server,
 999							     list) != 0)
1000			goto restart;
1001	}
1002	rcu_read_unlock();
1003	spin_unlock(&clp->cl_lock);
1004}
1005
1006static int pnfs_layout_bulk_list_reboot(struct list_head *list)
1007{
1008	struct pnfs_layout_hdr *lo;
1009	struct nfs_server *server;
1010	int ret;
1011
1012	list_for_each_entry(lo, list, plh_bulk_destroy) {
1013		server = NFS_SERVER(lo->plh_inode);
1014		ret = pnfs_layout_return_on_reboot(lo);
1015		switch (ret) {
1016		case 0:
1017			continue;
1018		case -NFS4ERR_BAD_STATEID:
1019			server->caps &= ~NFS_CAP_REBOOT_LAYOUTRETURN;
1020			break;
1021		case -NFS4ERR_NO_GRACE:
1022			break;
1023		default:
1024			goto err;
1025		}
1026		break;
1027	}
1028	return 0;
1029err:
1030	return ret;
1031}
1032
1033int pnfs_layout_handle_reboot(struct nfs_client *clp)
1034{
1035	LIST_HEAD(list);
1036	int ret = 0, ret2;
1037
1038	pnfs_layout_build_recover_list_byclient(clp, &list);
1039	if (!list_empty(&list))
1040		ret = pnfs_layout_bulk_list_reboot(&list);
1041	ret2 = pnfs_layout_do_destroy_byclid(clp, &list,
1042					     PNFS_LAYOUT_INVALIDATE);
1043	if (!ret)
1044		ret = ret2;
1045	return (ret == 0) ?  0 : -EAGAIN;
1046}
1047
1048static void
1049pnfs_set_layout_cred(struct pnfs_layout_hdr *lo, const struct cred *cred)
1050{
1051	const struct cred *old;
1052
1053	if (cred && cred_fscmp(lo->plh_lc_cred, cred) != 0) {
1054		old = xchg(&lo->plh_lc_cred, get_cred(cred));
1055		put_cred(old);
1056	}
1057}
1058
1059/* update lo->plh_stateid with new if is more recent */
1060void
1061pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
1062			const struct cred *cred, bool update_barrier)
1063{
1064	u32 oldseq = be32_to_cpu(lo->plh_stateid.seqid);
1065	u32 newseq = be32_to_cpu(new->seqid);
1066
1067	if (!pnfs_layout_is_valid(lo)) {
1068		pnfs_set_layout_cred(lo, cred);
1069		nfs4_stateid_copy(&lo->plh_stateid, new);
1070		lo->plh_barrier = newseq;
1071		pnfs_clear_layoutreturn_info(lo);
1072		clear_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
1073		return;
1074	}
1075
1076	if (pnfs_seqid_is_newer(newseq, oldseq))
1077		nfs4_stateid_copy(&lo->plh_stateid, new);
1078
1079	if (update_barrier) {
1080		pnfs_barrier_update(lo, newseq);
1081		return;
1082	}
1083	/*
1084	 * Because of wraparound, we want to keep the barrier
1085	 * "close" to the current seqids. We really only want to
1086	 * get here from a layoutget call.
1087	 */
1088	if (atomic_read(&lo->plh_outstanding) == 1)
1089		 pnfs_barrier_update(lo, be32_to_cpu(lo->plh_stateid.seqid));
1090}
1091
1092static bool
1093pnfs_layout_stateid_blocked(const struct pnfs_layout_hdr *lo,
1094		const nfs4_stateid *stateid)
1095{
1096	u32 seqid = be32_to_cpu(stateid->seqid);
1097
1098	return lo->plh_barrier && pnfs_seqid_is_newer(lo->plh_barrier, seqid);
1099}
1100
1101/* lget is set to 1 if called from inside send_layoutget call chain */
1102static bool
1103pnfs_layoutgets_blocked(const struct pnfs_layout_hdr *lo)
1104{
1105	return lo->plh_block_lgets ||
1106		test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
1107}
1108
1109static struct nfs_server *
1110pnfs_find_server(struct inode *inode, struct nfs_open_context *ctx)
1111{
1112	struct nfs_server *server;
1113
1114	if (inode) {
1115		server = NFS_SERVER(inode);
1116	} else {
1117		struct dentry *parent_dir = dget_parent(ctx->dentry);
1118		server = NFS_SERVER(parent_dir->d_inode);
1119		dput(parent_dir);
1120	}
1121	return server;
1122}
1123
1124static void nfs4_free_pages(struct page **pages, size_t size)
1125{
1126	int i;
1127
1128	if (!pages)
1129		return;
1130
1131	for (i = 0; i < size; i++) {
1132		if (!pages[i])
1133			break;
1134		__free_page(pages[i]);
1135	}
1136	kfree(pages);
1137}
1138
1139static struct page **nfs4_alloc_pages(size_t size, gfp_t gfp_flags)
1140{
1141	struct page **pages;
1142	int i;
1143
1144	pages = kmalloc_array(size, sizeof(struct page *), gfp_flags);
1145	if (!pages) {
1146		dprintk("%s: can't alloc array of %zu pages\n", __func__, size);
1147		return NULL;
1148	}
1149
1150	for (i = 0; i < size; i++) {
1151		pages[i] = alloc_page(gfp_flags);
1152		if (!pages[i]) {
1153			dprintk("%s: failed to allocate page\n", __func__);
1154			nfs4_free_pages(pages, i);
1155			return NULL;
1156		}
1157	}
1158
1159	return pages;
1160}
1161
1162static struct nfs4_layoutget *
1163pnfs_alloc_init_layoutget_args(struct inode *ino,
1164	   struct nfs_open_context *ctx,
1165	   const nfs4_stateid *stateid,
1166	   const struct pnfs_layout_range *range,
1167	   gfp_t gfp_flags)
1168{
1169	struct nfs_server *server = pnfs_find_server(ino, ctx);
1170	size_t max_reply_sz = server->pnfs_curr_ld->max_layoutget_response;
1171	size_t max_pages = max_response_pages(server);
1172	struct nfs4_layoutget *lgp;
1173
1174	dprintk("--> %s\n", __func__);
1175
1176	lgp = kzalloc(sizeof(*lgp), gfp_flags);
1177	if (lgp == NULL)
1178		return NULL;
1179
1180	if (max_reply_sz) {
1181		size_t npages = (max_reply_sz + PAGE_SIZE - 1) >> PAGE_SHIFT;
1182		if (npages < max_pages)
1183			max_pages = npages;
1184	}
1185
1186	lgp->args.layout.pages = nfs4_alloc_pages(max_pages, gfp_flags);
1187	if (!lgp->args.layout.pages) {
1188		kfree(lgp);
1189		return NULL;
1190	}
1191	lgp->args.layout.pglen = max_pages * PAGE_SIZE;
1192	lgp->res.layoutp = &lgp->args.layout;
1193
1194	/* Don't confuse uninitialised result and success */
1195	lgp->res.status = -NFS4ERR_DELAY;
1196
1197	lgp->args.minlength = PAGE_SIZE;
1198	if (lgp->args.minlength > range->length)
1199		lgp->args.minlength = range->length;
1200	if (ino) {
1201		loff_t i_size = i_size_read(ino);
1202
1203		if (range->iomode == IOMODE_READ) {
1204			if (range->offset >= i_size)
1205				lgp->args.minlength = 0;
1206			else if (i_size - range->offset < lgp->args.minlength)
1207				lgp->args.minlength = i_size - range->offset;
1208		}
1209	}
1210	lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
1211	pnfs_copy_range(&lgp->args.range, range);
1212	lgp->args.type = server->pnfs_curr_ld->id;
1213	lgp->args.inode = ino;
1214	lgp->args.ctx = get_nfs_open_context(ctx);
1215	nfs4_stateid_copy(&lgp->args.stateid, stateid);
1216	lgp->gfp_flags = gfp_flags;
1217	lgp->cred = ctx->cred;
1218	return lgp;
1219}
1220
1221void pnfs_layoutget_free(struct nfs4_layoutget *lgp)
1222{
1223	size_t max_pages = lgp->args.layout.pglen / PAGE_SIZE;
1224
1225	nfs4_free_pages(lgp->args.layout.pages, max_pages);
1226	pnfs_put_layout_hdr(lgp->lo);
1227	put_nfs_open_context(lgp->args.ctx);
1228	kfree(lgp);
1229}
1230
1231static void pnfs_clear_layoutcommit(struct inode *inode,
1232		struct list_head *head)
1233{
1234	struct nfs_inode *nfsi = NFS_I(inode);
1235	struct pnfs_layout_segment *lseg, *tmp;
1236
1237	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
1238		return;
1239	list_for_each_entry_safe(lseg, tmp, &nfsi->layout->plh_segs, pls_list) {
1240		if (!test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
1241			continue;
1242		pnfs_lseg_dec_and_remove_zero(lseg, head);
1243	}
1244}
1245
1246static void
1247pnfs_layoutreturn_retry_later_locked(struct pnfs_layout_hdr *lo,
1248				     const nfs4_stateid *arg_stateid,
1249				     const struct pnfs_layout_range *range)
1250{
1251	const struct pnfs_layout_segment *lseg;
1252	u32 seq = be32_to_cpu(arg_stateid->seqid);
1253
1254	if (pnfs_layout_is_valid(lo) &&
1255	    nfs4_stateid_match_other(&lo->plh_stateid, arg_stateid)) {
1256		list_for_each_entry(lseg, &lo->plh_return_segs, pls_list) {
1257			if (pnfs_seqid_is_newer(lseg->pls_seq, seq) ||
1258			    !pnfs_should_free_range(&lseg->pls_range, range))
1259				continue;
1260			pnfs_set_plh_return_info(lo, range->iomode, seq);
1261			break;
1262		}
1263	}
1264}
1265
1266void pnfs_layoutreturn_retry_later(struct pnfs_layout_hdr *lo,
1267				   const nfs4_stateid *arg_stateid,
1268				   const struct pnfs_layout_range *range)
1269{
1270	struct inode *inode = lo->plh_inode;
1271
1272	spin_lock(&inode->i_lock);
1273	pnfs_layoutreturn_retry_later_locked(lo, arg_stateid, range);
1274	pnfs_clear_layoutreturn_waitbit(lo);
1275	spin_unlock(&inode->i_lock);
1276}
1277
1278void pnfs_layoutreturn_free_lsegs(struct pnfs_layout_hdr *lo,
1279		const nfs4_stateid *arg_stateid,
1280		const struct pnfs_layout_range *range,
1281		const nfs4_stateid *stateid)
1282{
1283	struct inode *inode = lo->plh_inode;
1284	LIST_HEAD(freeme);
1285
1286	spin_lock(&inode->i_lock);
1287	if (!nfs4_stateid_match_other(&lo->plh_stateid, arg_stateid))
 
1288		goto out_unlock;
1289	if (stateid && pnfs_layout_is_valid(lo)) {
1290		u32 seq = be32_to_cpu(arg_stateid->seqid);
1291
1292		pnfs_mark_matching_lsegs_invalid(lo, &freeme, range, seq);
1293		pnfs_free_returned_lsegs(lo, &freeme, range, seq);
1294		pnfs_set_layout_stateid(lo, stateid, NULL, true);
1295	} else
1296		pnfs_mark_layout_stateid_invalid(lo, &freeme);
1297out_unlock:
1298	pnfs_clear_layoutreturn_waitbit(lo);
1299	spin_unlock(&inode->i_lock);
1300	pnfs_free_lseg_list(&freeme);
1301
1302}
1303
1304static bool
1305pnfs_prepare_layoutreturn(struct pnfs_layout_hdr *lo,
1306		nfs4_stateid *stateid,
1307		const struct cred **cred,
1308		enum pnfs_iomode *iomode)
1309{
1310	/* Serialise LAYOUTGET/LAYOUTRETURN */
1311	if (atomic_read(&lo->plh_outstanding) != 0 && lo->plh_return_seq == 0)
1312		return false;
1313	if (test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
1314		return false;
1315	set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
1316	pnfs_get_layout_hdr(lo);
1317	nfs4_stateid_copy(stateid, &lo->plh_stateid);
1318	*cred = get_cred(lo->plh_lc_cred);
1319	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags)) {
1320		if (lo->plh_return_seq != 0)
1321			stateid->seqid = cpu_to_be32(lo->plh_return_seq);
1322		if (iomode != NULL)
1323			*iomode = lo->plh_return_iomode;
1324		pnfs_clear_layoutreturn_info(lo);
1325	} else if (iomode != NULL)
1326		*iomode = IOMODE_ANY;
1327	pnfs_barrier_update(lo, be32_to_cpu(stateid->seqid));
1328	return true;
1329}
1330
1331static void
1332pnfs_init_layoutreturn_args(struct nfs4_layoutreturn_args *args,
1333		struct pnfs_layout_hdr *lo,
1334		const nfs4_stateid *stateid,
1335		enum pnfs_iomode iomode)
1336{
1337	struct inode *inode = lo->plh_inode;
1338
1339	args->layout_type = NFS_SERVER(inode)->pnfs_curr_ld->id;
1340	args->inode = inode;
1341	args->range.iomode = iomode;
1342	args->range.offset = 0;
1343	args->range.length = NFS4_MAX_UINT64;
1344	args->layout = lo;
1345	nfs4_stateid_copy(&args->stateid, stateid);
1346}
1347
1348static int
1349pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo,
1350		       const nfs4_stateid *stateid,
1351		       const struct cred **pcred,
1352		       enum pnfs_iomode iomode,
1353		       unsigned int flags)
1354{
1355	struct inode *ino = lo->plh_inode;
1356	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1357	struct nfs4_layoutreturn *lrp;
1358	const struct cred *cred = *pcred;
1359	int status = 0;
1360
1361	*pcred = NULL;
1362	lrp = kzalloc(sizeof(*lrp), nfs_io_gfp_mask());
1363	if (unlikely(lrp == NULL)) {
1364		status = -ENOMEM;
1365		spin_lock(&ino->i_lock);
1366		pnfs_clear_layoutreturn_waitbit(lo);
1367		spin_unlock(&ino->i_lock);
1368		put_cred(cred);
1369		pnfs_put_layout_hdr(lo);
1370		goto out;
1371	}
1372
1373	pnfs_init_layoutreturn_args(&lrp->args, lo, stateid, iomode);
1374	lrp->args.ld_private = &lrp->ld_private;
1375	lrp->clp = NFS_SERVER(ino)->nfs_client;
1376	lrp->cred = cred;
1377	if (ld->prepare_layoutreturn)
1378		ld->prepare_layoutreturn(&lrp->args);
1379
1380	status = nfs4_proc_layoutreturn(lrp, flags);
1381out:
1382	dprintk("<-- %s status: %d\n", __func__, status);
1383	return status;
1384}
1385
 
 
 
 
 
 
 
 
 
 
 
 
 
1386/* Return true if layoutreturn is needed */
1387static bool
1388pnfs_layout_need_return(struct pnfs_layout_hdr *lo)
1389{
1390	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1391		return false;
1392	return pnfs_mark_layout_stateid_return(lo, &lo->plh_return_segs,
1393					       lo->plh_return_iomode,
1394					       lo->plh_return_seq) != EBUSY;
1395}
1396
1397static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo)
1398{
1399	struct inode *inode= lo->plh_inode;
1400
1401	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1402		return;
1403	spin_lock(&inode->i_lock);
1404	if (pnfs_layout_need_return(lo)) {
1405		const struct cred *cred;
1406		nfs4_stateid stateid;
1407		enum pnfs_iomode iomode;
1408		bool send;
1409
1410		send = pnfs_prepare_layoutreturn(lo, &stateid, &cred, &iomode);
1411		spin_unlock(&inode->i_lock);
1412		if (send) {
1413			/* Send an async layoutreturn so we dont deadlock */
1414			pnfs_send_layoutreturn(lo, &stateid, &cred, iomode,
1415					       PNFS_FL_LAYOUTRETURN_ASYNC);
1416		}
1417	} else
1418		spin_unlock(&inode->i_lock);
1419}
1420
1421/*
1422 * Initiates a LAYOUTRETURN(FILE), and removes the pnfs_layout_hdr
1423 * when the layout segment list is empty.
1424 *
1425 * Note that a pnfs_layout_hdr can exist with an empty layout segment
1426 * list when LAYOUTGET has failed, or when LAYOUTGET succeeded, but the
1427 * deviceid is marked invalid.
1428 */
1429int
1430_pnfs_return_layout(struct inode *ino)
1431{
1432	struct pnfs_layout_hdr *lo = NULL;
1433	struct nfs_inode *nfsi = NFS_I(ino);
1434	struct pnfs_layout_range range = {
1435		.iomode		= IOMODE_ANY,
1436		.offset		= 0,
1437		.length		= NFS4_MAX_UINT64,
1438	};
1439	LIST_HEAD(tmp_list);
1440	const struct cred *cred;
1441	nfs4_stateid stateid;
1442	int status = 0;
1443	bool send, valid_layout;
1444
1445	dprintk("NFS: %s for inode %lu\n", __func__, ino->i_ino);
1446
1447	spin_lock(&ino->i_lock);
1448	lo = nfsi->layout;
1449	if (!lo) {
1450		spin_unlock(&ino->i_lock);
1451		dprintk("NFS: %s no layout to return\n", __func__);
1452		goto out;
1453	}
1454	/* Reference matched in nfs4_layoutreturn_release */
1455	pnfs_get_layout_hdr(lo);
1456	/* Is there an outstanding layoutreturn ? */
1457	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1458		spin_unlock(&ino->i_lock);
1459		if (wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1460					TASK_UNINTERRUPTIBLE))
1461			goto out_put_layout_hdr;
1462		spin_lock(&ino->i_lock);
1463	}
1464	valid_layout = pnfs_layout_is_valid(lo);
1465	pnfs_clear_layoutcommit(ino, &tmp_list);
1466	pnfs_mark_matching_lsegs_return(lo, &tmp_list, &range, 0);
1467
1468	if (NFS_SERVER(ino)->pnfs_curr_ld->return_range)
1469		NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo, &range);
1470
1471	/* Don't send a LAYOUTRETURN if list was initially empty */
1472	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) ||
1473			!valid_layout) {
1474		spin_unlock(&ino->i_lock);
1475		dprintk("NFS: %s no layout segments to return\n", __func__);
1476		goto out_wait_layoutreturn;
1477	}
1478
1479	send = pnfs_prepare_layoutreturn(lo, &stateid, &cred, NULL);
1480	spin_unlock(&ino->i_lock);
1481	if (send)
1482		status = pnfs_send_layoutreturn(lo, &stateid, &cred, IOMODE_ANY,
1483						0);
1484out_wait_layoutreturn:
1485	wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN, TASK_UNINTERRUPTIBLE);
1486out_put_layout_hdr:
1487	pnfs_free_lseg_list(&tmp_list);
1488	pnfs_put_layout_hdr(lo);
1489out:
1490	dprintk("<-- %s status: %d\n", __func__, status);
1491	return status;
1492}
1493
1494int
1495pnfs_commit_and_return_layout(struct inode *inode)
1496{
1497	struct pnfs_layout_hdr *lo;
1498	int ret;
1499
1500	spin_lock(&inode->i_lock);
1501	lo = NFS_I(inode)->layout;
1502	if (lo == NULL) {
1503		spin_unlock(&inode->i_lock);
1504		return 0;
1505	}
1506	pnfs_get_layout_hdr(lo);
1507	/* Block new layoutgets and read/write to ds */
1508	lo->plh_block_lgets++;
1509	spin_unlock(&inode->i_lock);
1510	filemap_fdatawait(inode->i_mapping);
1511	ret = pnfs_layoutcommit_inode(inode, true);
1512	if (ret == 0)
1513		ret = _pnfs_return_layout(inode);
1514	spin_lock(&inode->i_lock);
1515	lo->plh_block_lgets--;
1516	spin_unlock(&inode->i_lock);
1517	pnfs_put_layout_hdr(lo);
1518	return ret;
1519}
1520
1521static int pnfs_layout_return_on_reboot(struct pnfs_layout_hdr *lo)
1522{
1523	struct inode *inode = lo->plh_inode;
1524	const struct cred *cred;
1525
1526	spin_lock(&inode->i_lock);
1527	if (!pnfs_layout_is_valid(lo)) {
1528		spin_unlock(&inode->i_lock);
1529		return 0;
1530	}
1531	cred = get_cred(lo->plh_lc_cred);
1532	pnfs_get_layout_hdr(lo);
1533	spin_unlock(&inode->i_lock);
1534
1535	return pnfs_send_layoutreturn(lo, &zero_stateid, &cred, IOMODE_ANY,
1536				      PNFS_FL_LAYOUTRETURN_PRIVILEGED);
1537}
1538
1539bool pnfs_roc(struct inode *ino,
1540		struct nfs4_layoutreturn_args *args,
1541		struct nfs4_layoutreturn_res *res,
1542		const struct cred *cred)
1543{
1544	struct nfs_inode *nfsi = NFS_I(ino);
1545	struct nfs_open_context *ctx;
1546	struct nfs4_state *state;
1547	struct pnfs_layout_hdr *lo;
1548	struct pnfs_layout_segment *lseg, *next;
1549	const struct cred *lc_cred;
1550	nfs4_stateid stateid;
1551	enum pnfs_iomode iomode = 0;
1552	bool layoutreturn = false, roc = false;
1553	bool skip_read = false;
1554
1555	if (!nfs_have_layout(ino))
1556		return false;
1557retry:
1558	rcu_read_lock();
1559	spin_lock(&ino->i_lock);
1560	lo = nfsi->layout;
1561	if (!lo || !pnfs_layout_is_valid(lo) ||
1562	    test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1563		lo = NULL;
1564		goto out_noroc;
1565	}
1566	pnfs_get_layout_hdr(lo);
1567	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1568		spin_unlock(&ino->i_lock);
1569		rcu_read_unlock();
1570		wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1571				TASK_UNINTERRUPTIBLE);
1572		pnfs_put_layout_hdr(lo);
1573		goto retry;
1574	}
1575
1576	/* no roc if we hold a delegation */
1577	if (nfs4_check_delegation(ino, FMODE_READ)) {
1578		if (nfs4_check_delegation(ino, FMODE_WRITE))
1579			goto out_noroc;
1580		skip_read = true;
1581	}
1582
1583	list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
1584		state = ctx->state;
1585		if (state == NULL)
1586			continue;
1587		/* Don't return layout if there is open file state */
1588		if (state->state & FMODE_WRITE)
1589			goto out_noroc;
1590		if (state->state & FMODE_READ)
1591			skip_read = true;
1592	}
1593
1594
1595	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list) {
1596		if (skip_read && lseg->pls_range.iomode == IOMODE_READ)
1597			continue;
1598		/* If we are sending layoutreturn, invalidate all valid lsegs */
1599		if (!test_and_clear_bit(NFS_LSEG_ROC, &lseg->pls_flags))
1600			continue;
1601		/*
1602		 * Note: mark lseg for return so pnfs_layout_remove_lseg
1603		 * doesn't invalidate the layout for us.
1604		 */
1605		set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
1606		if (!mark_lseg_invalid(lseg, &lo->plh_return_segs))
1607			continue;
1608		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
1609	}
1610
1611	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1612		goto out_noroc;
1613
1614	/* ROC in two conditions:
1615	 * 1. there are ROC lsegs
1616	 * 2. we don't send layoutreturn
1617	 */
1618	/* lo ref dropped in pnfs_roc_release() */
1619	layoutreturn = pnfs_prepare_layoutreturn(lo, &stateid, &lc_cred, &iomode);
1620	/* If the creds don't match, we can't compound the layoutreturn */
1621	if (!layoutreturn || cred_fscmp(cred, lc_cred) != 0)
1622		goto out_noroc;
1623
1624	roc = layoutreturn;
1625	pnfs_init_layoutreturn_args(args, lo, &stateid, iomode);
1626	res->lrs_present = 0;
1627	layoutreturn = false;
1628	put_cred(lc_cred);
1629
1630out_noroc:
1631	spin_unlock(&ino->i_lock);
1632	rcu_read_unlock();
1633	pnfs_layoutcommit_inode(ino, true);
1634	if (roc) {
1635		struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1636		if (ld->prepare_layoutreturn)
1637			ld->prepare_layoutreturn(args);
1638		pnfs_put_layout_hdr(lo);
1639		return true;
1640	}
1641	if (layoutreturn)
1642		pnfs_send_layoutreturn(lo, &stateid, &lc_cred, iomode, 0);
1643	pnfs_put_layout_hdr(lo);
1644	return false;
1645}
1646
1647int pnfs_roc_done(struct rpc_task *task, struct nfs4_layoutreturn_args **argpp,
1648		  struct nfs4_layoutreturn_res **respp, int *ret)
1649{
1650	struct nfs4_layoutreturn_args *arg = *argpp;
1651	int retval = -EAGAIN;
1652
1653	if (!arg)
1654		return 0;
1655	/* Handle Layoutreturn errors */
1656	switch (*ret) {
1657	case 0:
1658		retval = 0;
1659		break;
1660	case -NFS4ERR_NOMATCHING_LAYOUT:
1661		/* Was there an RPC level error? If not, retry */
1662		if (task->tk_rpc_status == 0)
1663			break;
1664		/* If the call was not sent, let caller handle it */
1665		if (!RPC_WAS_SENT(task))
1666			return 0;
1667		/*
1668		 * Otherwise, assume the call succeeded and
1669		 * that we need to release the layout
1670		 */
1671		*ret = 0;
1672		(*respp)->lrs_present = 0;
1673		retval = 0;
1674		break;
1675	case -NFS4ERR_DELAY:
1676		/* Let the caller handle the retry */
1677		*ret = -NFS4ERR_NOMATCHING_LAYOUT;
1678		return 0;
1679	case -NFS4ERR_OLD_STATEID:
1680		if (!nfs4_layout_refresh_old_stateid(&arg->stateid,
1681						     &arg->range, arg->inode))
1682			break;
1683		*ret = -NFS4ERR_NOMATCHING_LAYOUT;
1684		return -EAGAIN;
1685	}
1686	*argpp = NULL;
1687	*respp = NULL;
1688	return retval;
1689}
1690
1691void pnfs_roc_release(struct nfs4_layoutreturn_args *args,
1692		      struct nfs4_layoutreturn_res *res, int ret)
 
1693{
1694	struct pnfs_layout_hdr *lo = args->layout;
1695	struct inode *inode = args->inode;
1696	const nfs4_stateid *res_stateid = NULL;
1697	struct nfs4_xdr_opaque_data *ld_private = args->ld_private;
1698
1699	switch (ret) {
1700	case -NFS4ERR_BADSESSION:
1701	case -NFS4ERR_DEADSESSION:
1702	case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1703	case -NFS4ERR_NOMATCHING_LAYOUT:
1704		spin_lock(&inode->i_lock);
1705		pnfs_layoutreturn_retry_later_locked(lo, &args->stateid,
1706						     &args->range);
 
1707		pnfs_clear_layoutreturn_waitbit(lo);
1708		spin_unlock(&inode->i_lock);
1709		break;
1710	case 0:
1711		if (res->lrs_present)
1712			res_stateid = &res->stateid;
1713		fallthrough;
1714	default:
1715		pnfs_layoutreturn_free_lsegs(lo, &args->stateid, &args->range,
1716					     res_stateid);
1717	}
1718	trace_nfs4_layoutreturn_on_close(args->inode, &args->stateid, ret);
1719	if (ld_private && ld_private->ops && ld_private->ops->free)
1720		ld_private->ops->free(ld_private);
1721	pnfs_put_layout_hdr(lo);
1722}
1723
1724bool pnfs_wait_on_layoutreturn(struct inode *ino, struct rpc_task *task)
1725{
1726	struct nfs_inode *nfsi = NFS_I(ino);
1727        struct pnfs_layout_hdr *lo;
1728        bool sleep = false;
1729
1730	/* we might not have grabbed lo reference. so need to check under
1731	 * i_lock */
1732        spin_lock(&ino->i_lock);
1733        lo = nfsi->layout;
1734        if (lo && test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
1735                rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
1736                sleep = true;
1737	}
1738        spin_unlock(&ino->i_lock);
1739        return sleep;
1740}
1741
1742/*
1743 * Compare two layout segments for sorting into layout cache.
1744 * We want to preferentially return RW over RO layouts, so ensure those
1745 * are seen first.
1746 */
1747static s64
1748pnfs_lseg_range_cmp(const struct pnfs_layout_range *l1,
1749	   const struct pnfs_layout_range *l2)
1750{
1751	s64 d;
1752
1753	/* high offset > low offset */
1754	d = l1->offset - l2->offset;
1755	if (d)
1756		return d;
1757
1758	/* short length > long length */
1759	d = l2->length - l1->length;
1760	if (d)
1761		return d;
1762
1763	/* read > read/write */
1764	return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
1765}
1766
1767static bool
1768pnfs_lseg_range_is_after(const struct pnfs_layout_range *l1,
1769		const struct pnfs_layout_range *l2)
1770{
1771	return pnfs_lseg_range_cmp(l1, l2) > 0;
1772}
1773
1774static bool
1775pnfs_lseg_no_merge(struct pnfs_layout_segment *lseg,
1776		struct pnfs_layout_segment *old)
1777{
1778	return false;
1779}
1780
1781void
1782pnfs_generic_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1783		   struct pnfs_layout_segment *lseg,
1784		   bool (*is_after)(const struct pnfs_layout_range *,
1785			   const struct pnfs_layout_range *),
1786		   bool (*do_merge)(struct pnfs_layout_segment *,
1787			   struct pnfs_layout_segment *),
1788		   struct list_head *free_me)
1789{
1790	struct pnfs_layout_segment *lp, *tmp;
1791
1792	dprintk("%s:Begin\n", __func__);
1793
1794	list_for_each_entry_safe(lp, tmp, &lo->plh_segs, pls_list) {
1795		if (test_bit(NFS_LSEG_VALID, &lp->pls_flags) == 0)
1796			continue;
1797		if (do_merge(lseg, lp)) {
1798			mark_lseg_invalid(lp, free_me);
1799			continue;
1800		}
1801		if (is_after(&lseg->pls_range, &lp->pls_range))
1802			continue;
1803		list_add_tail(&lseg->pls_list, &lp->pls_list);
1804		dprintk("%s: inserted lseg %p "
1805			"iomode %d offset %llu length %llu before "
1806			"lp %p iomode %d offset %llu length %llu\n",
1807			__func__, lseg, lseg->pls_range.iomode,
1808			lseg->pls_range.offset, lseg->pls_range.length,
1809			lp, lp->pls_range.iomode, lp->pls_range.offset,
1810			lp->pls_range.length);
1811		goto out;
1812	}
1813	list_add_tail(&lseg->pls_list, &lo->plh_segs);
1814	dprintk("%s: inserted lseg %p "
1815		"iomode %d offset %llu length %llu at tail\n",
1816		__func__, lseg, lseg->pls_range.iomode,
1817		lseg->pls_range.offset, lseg->pls_range.length);
1818out:
1819	pnfs_get_layout_hdr(lo);
1820
1821	dprintk("%s:Return\n", __func__);
1822}
1823EXPORT_SYMBOL_GPL(pnfs_generic_layout_insert_lseg);
1824
1825static void
1826pnfs_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1827		   struct pnfs_layout_segment *lseg,
1828		   struct list_head *free_me)
1829{
1830	struct inode *inode = lo->plh_inode;
1831	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
1832
1833	if (ld->add_lseg != NULL)
1834		ld->add_lseg(lo, lseg, free_me);
1835	else
1836		pnfs_generic_layout_insert_lseg(lo, lseg,
1837				pnfs_lseg_range_is_after,
1838				pnfs_lseg_no_merge,
1839				free_me);
1840}
1841
1842static struct pnfs_layout_hdr *
1843alloc_init_layout_hdr(struct inode *ino,
1844		      struct nfs_open_context *ctx,
1845		      gfp_t gfp_flags)
1846{
1847	struct pnfs_layout_hdr *lo;
1848
1849	lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
1850	if (!lo)
1851		return NULL;
1852	refcount_set(&lo->plh_refcount, 1);
1853	INIT_LIST_HEAD(&lo->plh_layouts);
1854	INIT_LIST_HEAD(&lo->plh_segs);
1855	INIT_LIST_HEAD(&lo->plh_return_segs);
1856	INIT_LIST_HEAD(&lo->plh_bulk_destroy);
1857	lo->plh_inode = ino;
1858	lo->plh_lc_cred = get_cred(ctx->cred);
1859	lo->plh_flags |= 1 << NFS_LAYOUT_INVALID_STID;
1860	return lo;
1861}
1862
1863static struct pnfs_layout_hdr *
1864pnfs_find_alloc_layout(struct inode *ino,
1865		       struct nfs_open_context *ctx,
1866		       gfp_t gfp_flags)
1867	__releases(&ino->i_lock)
1868	__acquires(&ino->i_lock)
1869{
1870	struct nfs_inode *nfsi = NFS_I(ino);
1871	struct pnfs_layout_hdr *new = NULL;
1872
1873	dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
1874
1875	if (nfsi->layout != NULL)
1876		goto out_existing;
1877	spin_unlock(&ino->i_lock);
1878	new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
1879	spin_lock(&ino->i_lock);
1880
1881	if (likely(nfsi->layout == NULL)) {	/* Won the race? */
1882		nfsi->layout = new;
1883		return new;
1884	} else if (new != NULL)
1885		pnfs_free_layout_hdr(new);
1886out_existing:
1887	pnfs_get_layout_hdr(nfsi->layout);
1888	return nfsi->layout;
1889}
1890
1891/*
1892 * iomode matching rules:
1893 * iomode	lseg	strict match
1894 *                      iomode
1895 * -----	-----	------ -----
1896 * ANY		READ	N/A    true
1897 * ANY		RW	N/A    true
1898 * RW		READ	N/A    false
1899 * RW		RW	N/A    true
1900 * READ		READ	N/A    true
1901 * READ		RW	true   false
1902 * READ		RW	false  true
1903 */
1904static bool
1905pnfs_lseg_range_match(const struct pnfs_layout_range *ls_range,
1906		 const struct pnfs_layout_range *range,
1907		 bool strict_iomode)
1908{
1909	struct pnfs_layout_range range1;
1910
1911	if ((range->iomode == IOMODE_RW &&
1912	     ls_range->iomode != IOMODE_RW) ||
1913	    (range->iomode != ls_range->iomode &&
1914	     strict_iomode) ||
1915	    !pnfs_lseg_range_intersecting(ls_range, range))
1916		return false;
1917
1918	/* range1 covers only the first byte in the range */
1919	range1 = *range;
1920	range1.length = 1;
1921	return pnfs_lseg_range_contained(ls_range, &range1);
1922}
1923
1924/*
1925 * lookup range in layout
1926 */
1927static struct pnfs_layout_segment *
1928pnfs_find_lseg(struct pnfs_layout_hdr *lo,
1929		struct pnfs_layout_range *range,
1930		bool strict_iomode)
1931{
1932	struct pnfs_layout_segment *lseg, *ret = NULL;
1933
1934	dprintk("%s:Begin\n", __func__);
1935
1936	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
1937		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
1938		    pnfs_lseg_range_match(&lseg->pls_range, range,
1939					  strict_iomode)) {
1940			ret = pnfs_get_lseg(lseg);
1941			break;
1942		}
1943	}
1944
1945	dprintk("%s:Return lseg %p ref %d\n",
1946		__func__, ret, ret ? refcount_read(&ret->pls_refcount) : 0);
1947	return ret;
1948}
1949
1950/*
1951 * Use mdsthreshold hints set at each OPEN to determine if I/O should go
1952 * to the MDS or over pNFS
1953 *
1954 * The nfs_inode read_io and write_io fields are cumulative counters reset
1955 * when there are no layout segments. Note that in pnfs_update_layout iomode
1956 * is set to IOMODE_READ for a READ request, and set to IOMODE_RW for a
1957 * WRITE request.
1958 *
1959 * A return of true means use MDS I/O.
1960 *
1961 * From rfc 5661:
1962 * If a file's size is smaller than the file size threshold, data accesses
1963 * SHOULD be sent to the metadata server.  If an I/O request has a length that
1964 * is below the I/O size threshold, the I/O SHOULD be sent to the metadata
1965 * server.  If both file size and I/O size are provided, the client SHOULD
1966 * reach or exceed  both thresholds before sending its read or write
1967 * requests to the data server.
1968 */
1969static bool pnfs_within_mdsthreshold(struct nfs_open_context *ctx,
1970				     struct inode *ino, int iomode)
1971{
1972	struct nfs4_threshold *t = ctx->mdsthreshold;
1973	struct nfs_inode *nfsi = NFS_I(ino);
1974	loff_t fsize = i_size_read(ino);
1975	bool size = false, size_set = false, io = false, io_set = false, ret = false;
1976
1977	if (t == NULL)
1978		return ret;
1979
1980	dprintk("%s bm=0x%x rd_sz=%llu wr_sz=%llu rd_io=%llu wr_io=%llu\n",
1981		__func__, t->bm, t->rd_sz, t->wr_sz, t->rd_io_sz, t->wr_io_sz);
1982
1983	switch (iomode) {
1984	case IOMODE_READ:
1985		if (t->bm & THRESHOLD_RD) {
1986			dprintk("%s fsize %llu\n", __func__, fsize);
1987			size_set = true;
1988			if (fsize < t->rd_sz)
1989				size = true;
1990		}
1991		if (t->bm & THRESHOLD_RD_IO) {
1992			dprintk("%s nfsi->read_io %llu\n", __func__,
1993				nfsi->read_io);
1994			io_set = true;
1995			if (nfsi->read_io < t->rd_io_sz)
1996				io = true;
1997		}
1998		break;
1999	case IOMODE_RW:
2000		if (t->bm & THRESHOLD_WR) {
2001			dprintk("%s fsize %llu\n", __func__, fsize);
2002			size_set = true;
2003			if (fsize < t->wr_sz)
2004				size = true;
2005		}
2006		if (t->bm & THRESHOLD_WR_IO) {
2007			dprintk("%s nfsi->write_io %llu\n", __func__,
2008				nfsi->write_io);
2009			io_set = true;
2010			if (nfsi->write_io < t->wr_io_sz)
2011				io = true;
2012		}
2013		break;
2014	}
2015	if (size_set && io_set) {
2016		if (size && io)
2017			ret = true;
2018	} else if (size || io)
2019		ret = true;
2020
2021	dprintk("<-- %s size %d io %d ret %d\n", __func__, size, io, ret);
2022	return ret;
2023}
2024
2025static int pnfs_prepare_to_retry_layoutget(struct pnfs_layout_hdr *lo)
2026{
2027	/*
2028	 * send layoutcommit as it can hold up layoutreturn due to lseg
2029	 * reference
2030	 */
2031	pnfs_layoutcommit_inode(lo->plh_inode, false);
2032	return wait_on_bit_action(&lo->plh_flags, NFS_LAYOUT_RETURN,
2033				   nfs_wait_bit_killable,
2034				   TASK_KILLABLE|TASK_FREEZABLE_UNSAFE);
2035}
2036
2037static void nfs_layoutget_begin(struct pnfs_layout_hdr *lo)
2038{
2039	atomic_inc(&lo->plh_outstanding);
2040}
2041
2042static void nfs_layoutget_end(struct pnfs_layout_hdr *lo)
2043{
2044	if (atomic_dec_and_test(&lo->plh_outstanding) &&
2045	    test_and_clear_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags))
2046		wake_up_bit(&lo->plh_flags, NFS_LAYOUT_DRAIN);
2047}
2048
2049static bool pnfs_is_first_layoutget(struct pnfs_layout_hdr *lo)
2050{
2051	return test_bit(NFS_LAYOUT_FIRST_LAYOUTGET, &lo->plh_flags);
2052}
2053
2054static void pnfs_clear_first_layoutget(struct pnfs_layout_hdr *lo)
2055{
2056	unsigned long *bitlock = &lo->plh_flags;
2057
2058	clear_bit_unlock(NFS_LAYOUT_FIRST_LAYOUTGET, bitlock);
2059	smp_mb__after_atomic();
2060	wake_up_bit(bitlock, NFS_LAYOUT_FIRST_LAYOUTGET);
2061}
2062
2063static void _add_to_server_list(struct pnfs_layout_hdr *lo,
2064				struct nfs_server *server)
2065{
2066	if (!test_and_set_bit(NFS_LAYOUT_HASHED, &lo->plh_flags)) {
2067		struct nfs_client *clp = server->nfs_client;
2068
2069		/* The lo must be on the clp list if there is any
2070		 * chance of a CB_LAYOUTRECALL(FILE) coming in.
2071		 */
2072		spin_lock(&clp->cl_lock);
2073		list_add_tail_rcu(&lo->plh_layouts, &server->layouts);
2074		spin_unlock(&clp->cl_lock);
2075	}
2076}
2077
2078/*
2079 * Layout segment is retreived from the server if not cached.
2080 * The appropriate layout segment is referenced and returned to the caller.
2081 */
2082struct pnfs_layout_segment *
2083pnfs_update_layout(struct inode *ino,
2084		   struct nfs_open_context *ctx,
2085		   loff_t pos,
2086		   u64 count,
2087		   enum pnfs_iomode iomode,
2088		   bool strict_iomode,
2089		   gfp_t gfp_flags)
2090{
2091	struct pnfs_layout_range arg = {
2092		.iomode = iomode,
2093		.offset = pos,
2094		.length = count,
2095	};
2096	unsigned pg_offset;
2097	struct nfs_server *server = NFS_SERVER(ino);
2098	struct nfs_client *clp = server->nfs_client;
2099	struct pnfs_layout_hdr *lo = NULL;
2100	struct pnfs_layout_segment *lseg = NULL;
2101	struct nfs4_layoutget *lgp;
2102	nfs4_stateid stateid;
2103	struct nfs4_exception exception = {
2104		.inode = ino,
2105	};
2106	unsigned long giveup = jiffies + (clp->cl_lease_time << 1);
2107	bool first;
2108
2109	if (!pnfs_enabled_sb(NFS_SERVER(ino))) {
2110		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2111				 PNFS_UPDATE_LAYOUT_NO_PNFS);
2112		goto out;
2113	}
2114
2115	if (pnfs_within_mdsthreshold(ctx, ino, iomode)) {
2116		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2117				 PNFS_UPDATE_LAYOUT_MDSTHRESH);
2118		goto out;
2119	}
2120
2121lookup_again:
2122	if (!nfs4_valid_open_stateid(ctx->state)) {
2123		trace_pnfs_update_layout(ino, pos, count,
2124					 iomode, lo, lseg,
2125					 PNFS_UPDATE_LAYOUT_INVALID_OPEN);
2126		lseg = ERR_PTR(-EIO);
2127		goto out;
2128	}
2129
2130	lseg = ERR_PTR(nfs4_client_recover_expired_lease(clp));
2131	if (IS_ERR(lseg))
2132		goto out;
2133	first = false;
2134	spin_lock(&ino->i_lock);
2135	lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
2136	if (lo == NULL) {
2137		spin_unlock(&ino->i_lock);
2138		lseg = ERR_PTR(-ENOMEM);
2139		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2140				 PNFS_UPDATE_LAYOUT_NOMEM);
2141		goto out;
2142	}
2143
2144	/* Do we even need to bother with this? */
2145	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
2146		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2147				 PNFS_UPDATE_LAYOUT_BULK_RECALL);
2148		dprintk("%s matches recall, use MDS\n", __func__);
2149		goto out_unlock;
2150	}
2151
2152	/* if LAYOUTGET already failed once we don't try again */
2153	if (pnfs_layout_io_test_failed(lo, iomode)) {
2154		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2155				 PNFS_UPDATE_LAYOUT_IO_TEST_FAIL);
2156		goto out_unlock;
2157	}
2158
2159	/*
2160	 * If the layout segment list is empty, but there are outstanding
2161	 * layoutget calls, then they might be subject to a layoutrecall.
2162	 */
2163	if (test_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags) &&
2164	    atomic_read(&lo->plh_outstanding) != 0) {
2165		spin_unlock(&ino->i_lock);
2166		lseg = ERR_PTR(wait_on_bit(&lo->plh_flags, NFS_LAYOUT_DRAIN,
2167					   TASK_KILLABLE));
2168		if (IS_ERR(lseg))
2169			goto out_put_layout_hdr;
2170		pnfs_put_layout_hdr(lo);
2171		goto lookup_again;
2172	}
2173
2174	/*
2175	 * Because we free lsegs when sending LAYOUTRETURN, we need to wait
2176	 * for LAYOUTRETURN.
2177	 */
2178	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
2179		spin_unlock(&ino->i_lock);
2180		dprintk("%s wait for layoutreturn\n", __func__);
2181		lseg = ERR_PTR(pnfs_prepare_to_retry_layoutget(lo));
2182		if (!IS_ERR(lseg)) {
2183			pnfs_put_layout_hdr(lo);
2184			dprintk("%s retrying\n", __func__);
2185			trace_pnfs_update_layout(ino, pos, count, iomode, lo,
2186						 lseg,
2187						 PNFS_UPDATE_LAYOUT_RETRY);
2188			goto lookup_again;
2189		}
2190		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2191					 PNFS_UPDATE_LAYOUT_RETURN);
2192		goto out_put_layout_hdr;
2193	}
2194
2195	lseg = pnfs_find_lseg(lo, &arg, strict_iomode);
2196	if (lseg) {
2197		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2198				PNFS_UPDATE_LAYOUT_FOUND_CACHED);
2199		goto out_unlock;
2200	}
2201
2202	/*
2203	 * Choose a stateid for the LAYOUTGET. If we don't have a layout
2204	 * stateid, or it has been invalidated, then we must use the open
2205	 * stateid.
2206	 */
2207	if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags)) {
2208		int status;
2209
2210		/*
2211		 * The first layoutget for the file. Need to serialize per
2212		 * RFC 5661 Errata 3208.
2213		 */
2214		if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET,
2215				     &lo->plh_flags)) {
2216			spin_unlock(&ino->i_lock);
2217			lseg = ERR_PTR(wait_on_bit(&lo->plh_flags,
2218						NFS_LAYOUT_FIRST_LAYOUTGET,
2219						TASK_KILLABLE));
2220			if (IS_ERR(lseg))
2221				goto out_put_layout_hdr;
2222			pnfs_put_layout_hdr(lo);
2223			dprintk("%s retrying\n", __func__);
2224			goto lookup_again;
2225		}
2226
2227		spin_unlock(&ino->i_lock);
2228		first = true;
2229		status = nfs4_select_rw_stateid(ctx->state,
2230					iomode == IOMODE_RW ? FMODE_WRITE : FMODE_READ,
2231					NULL, &stateid, NULL);
2232		if (status != 0) {
2233			lseg = ERR_PTR(status);
2234			trace_pnfs_update_layout(ino, pos, count,
2235					iomode, lo, lseg,
2236					PNFS_UPDATE_LAYOUT_INVALID_OPEN);
2237			nfs4_schedule_stateid_recovery(server, ctx->state);
2238			pnfs_clear_first_layoutget(lo);
2239			pnfs_put_layout_hdr(lo);
2240			goto lookup_again;
2241		}
2242		spin_lock(&ino->i_lock);
2243	} else {
2244		nfs4_stateid_copy(&stateid, &lo->plh_stateid);
2245	}
2246
2247	if (pnfs_layoutgets_blocked(lo)) {
2248		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2249				PNFS_UPDATE_LAYOUT_BLOCKED);
2250		goto out_unlock;
2251	}
2252	nfs_layoutget_begin(lo);
2253	spin_unlock(&ino->i_lock);
2254
2255	_add_to_server_list(lo, server);
2256
2257	pg_offset = arg.offset & ~PAGE_MASK;
2258	if (pg_offset) {
2259		arg.offset -= pg_offset;
2260		arg.length += pg_offset;
2261	}
2262	if (arg.length != NFS4_MAX_UINT64)
2263		arg.length = PAGE_ALIGN(arg.length);
2264
2265	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &stateid, &arg, gfp_flags);
2266	if (!lgp) {
2267		lseg = ERR_PTR(-ENOMEM);
2268		trace_pnfs_update_layout(ino, pos, count, iomode, lo, NULL,
2269					 PNFS_UPDATE_LAYOUT_NOMEM);
2270		nfs_layoutget_end(lo);
2271		goto out_put_layout_hdr;
2272	}
2273
2274	lgp->lo = lo;
2275	pnfs_get_layout_hdr(lo);
2276
2277	lseg = nfs4_proc_layoutget(lgp, &exception);
2278	trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2279				 PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET);
2280	nfs_layoutget_end(lo);
2281	if (IS_ERR(lseg)) {
2282		switch(PTR_ERR(lseg)) {
2283		case -EBUSY:
2284			if (time_after(jiffies, giveup))
2285				lseg = NULL;
2286			break;
2287		case -ERECALLCONFLICT:
2288		case -EAGAIN:
2289			break;
2290		case -ENODATA:
2291			/* The server returned NFS4ERR_LAYOUTUNAVAILABLE */
2292			pnfs_layout_set_fail_bit(
2293				lo, pnfs_iomode_to_fail_bit(iomode));
2294			lseg = NULL;
2295			goto out_put_layout_hdr;
2296		default:
2297			if (!nfs_error_is_fatal(PTR_ERR(lseg))) {
2298				pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2299				lseg = NULL;
2300			}
2301			goto out_put_layout_hdr;
2302		}
2303		if (lseg) {
2304			if (!exception.retry)
2305				goto out_put_layout_hdr;
2306			if (first)
2307				pnfs_clear_first_layoutget(lo);
2308			trace_pnfs_update_layout(ino, pos, count,
2309				iomode, lo, lseg, PNFS_UPDATE_LAYOUT_RETRY);
2310			pnfs_put_layout_hdr(lo);
2311			goto lookup_again;
2312		}
2313	} else {
2314		pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2315	}
2316
2317out_put_layout_hdr:
2318	if (first)
2319		pnfs_clear_first_layoutget(lo);
2320	trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2321				 PNFS_UPDATE_LAYOUT_EXIT);
2322	pnfs_put_layout_hdr(lo);
2323out:
2324	dprintk("%s: inode %s/%llu pNFS layout segment %s for "
2325			"(%s, offset: %llu, length: %llu)\n",
2326			__func__, ino->i_sb->s_id,
2327			(unsigned long long)NFS_FILEID(ino),
2328			IS_ERR_OR_NULL(lseg) ? "not found" : "found",
2329			iomode==IOMODE_RW ?  "read/write" : "read-only",
2330			(unsigned long long)pos,
2331			(unsigned long long)count);
2332	return lseg;
2333out_unlock:
2334	spin_unlock(&ino->i_lock);
2335	goto out_put_layout_hdr;
2336}
2337EXPORT_SYMBOL_GPL(pnfs_update_layout);
2338
2339static bool
2340pnfs_sanity_check_layout_range(struct pnfs_layout_range *range)
2341{
2342	switch (range->iomode) {
2343	case IOMODE_READ:
2344	case IOMODE_RW:
2345		break;
2346	default:
2347		return false;
2348	}
2349	if (range->offset == NFS4_MAX_UINT64)
2350		return false;
2351	if (range->length == 0)
2352		return false;
2353	if (range->length != NFS4_MAX_UINT64 &&
2354	    range->length > NFS4_MAX_UINT64 - range->offset)
2355		return false;
2356	return true;
2357}
2358
2359static struct pnfs_layout_hdr *
2360_pnfs_grab_empty_layout(struct inode *ino, struct nfs_open_context *ctx)
2361{
2362	struct pnfs_layout_hdr *lo;
2363
2364	spin_lock(&ino->i_lock);
2365	lo = pnfs_find_alloc_layout(ino, ctx, nfs_io_gfp_mask());
2366	if (!lo)
2367		goto out_unlock;
2368	if (!test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags))
2369		goto out_unlock;
2370	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
2371		goto out_unlock;
2372	if (pnfs_layoutgets_blocked(lo))
2373		goto out_unlock;
2374	if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET, &lo->plh_flags))
2375		goto out_unlock;
2376	nfs_layoutget_begin(lo);
2377	spin_unlock(&ino->i_lock);
2378	_add_to_server_list(lo, NFS_SERVER(ino));
2379	return lo;
2380
2381out_unlock:
2382	spin_unlock(&ino->i_lock);
2383	pnfs_put_layout_hdr(lo);
2384	return NULL;
2385}
2386
2387static void _lgopen_prepare_attached(struct nfs4_opendata *data,
2388				     struct nfs_open_context *ctx)
2389{
2390	struct inode *ino = data->dentry->d_inode;
2391	struct pnfs_layout_range rng = {
2392		.iomode = (data->o_arg.fmode & FMODE_WRITE) ?
2393			  IOMODE_RW: IOMODE_READ,
2394		.offset = 0,
2395		.length = NFS4_MAX_UINT64,
2396	};
2397	struct nfs4_layoutget *lgp;
2398	struct pnfs_layout_hdr *lo;
2399
2400	/* Heuristic: don't send layoutget if we have cached data */
2401	if (rng.iomode == IOMODE_READ &&
2402	   (i_size_read(ino) == 0 || ino->i_mapping->nrpages != 0))
2403		return;
2404
2405	lo = _pnfs_grab_empty_layout(ino, ctx);
2406	if (!lo)
2407		return;
2408	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &current_stateid, &rng,
2409					     nfs_io_gfp_mask());
2410	if (!lgp) {
2411		pnfs_clear_first_layoutget(lo);
2412		nfs_layoutget_end(lo);
2413		pnfs_put_layout_hdr(lo);
2414		return;
2415	}
2416	lgp->lo = lo;
2417	data->lgp = lgp;
2418	data->o_arg.lg_args = &lgp->args;
2419	data->o_res.lg_res = &lgp->res;
2420}
2421
2422static void _lgopen_prepare_floating(struct nfs4_opendata *data,
2423				     struct nfs_open_context *ctx)
2424{
2425	struct inode *ino = data->dentry->d_inode;
2426	struct pnfs_layout_range rng = {
2427		.iomode = (data->o_arg.fmode & FMODE_WRITE) ?
2428			  IOMODE_RW: IOMODE_READ,
2429		.offset = 0,
2430		.length = NFS4_MAX_UINT64,
2431	};
2432	struct nfs4_layoutget *lgp;
2433
2434	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &current_stateid, &rng,
2435					     nfs_io_gfp_mask());
2436	if (!lgp)
2437		return;
2438	data->lgp = lgp;
2439	data->o_arg.lg_args = &lgp->args;
2440	data->o_res.lg_res = &lgp->res;
2441}
2442
2443void pnfs_lgopen_prepare(struct nfs4_opendata *data,
2444			 struct nfs_open_context *ctx)
2445{
2446	struct nfs_server *server = NFS_SERVER(data->dir->d_inode);
2447
2448	if (!(pnfs_enabled_sb(server) &&
2449	      server->pnfs_curr_ld->flags & PNFS_LAYOUTGET_ON_OPEN))
2450		return;
2451	/* Could check on max_ops, but currently hardcoded high enough */
2452	if (!nfs_server_capable(data->dir->d_inode, NFS_CAP_LGOPEN))
2453		return;
2454	if (data->lgp)
2455		return;
2456	if (data->state)
2457		_lgopen_prepare_attached(data, ctx);
2458	else
2459		_lgopen_prepare_floating(data, ctx);
2460}
2461
2462void pnfs_parse_lgopen(struct inode *ino, struct nfs4_layoutget *lgp,
2463		       struct nfs_open_context *ctx)
2464{
2465	struct pnfs_layout_hdr *lo;
2466	struct pnfs_layout_segment *lseg;
2467	struct nfs_server *srv = NFS_SERVER(ino);
2468	u32 iomode;
2469
2470	if (!lgp)
2471		return;
2472	dprintk("%s: entered with status %i\n", __func__, lgp->res.status);
2473	if (lgp->res.status) {
2474		switch (lgp->res.status) {
2475		default:
2476			break;
2477		/*
2478		 * Halt lgopen attempts if the server doesn't recognise
2479		 * the "current stateid" value, the layout type, or the
2480		 * layoutget operation as being valid.
2481		 * Also if it complains about too many ops in the compound
2482		 * or of the request/reply being too big.
2483		 */
2484		case -NFS4ERR_BAD_STATEID:
2485		case -NFS4ERR_NOTSUPP:
2486		case -NFS4ERR_REP_TOO_BIG:
2487		case -NFS4ERR_REP_TOO_BIG_TO_CACHE:
2488		case -NFS4ERR_REQ_TOO_BIG:
2489		case -NFS4ERR_TOO_MANY_OPS:
2490		case -NFS4ERR_UNKNOWN_LAYOUTTYPE:
2491			srv->caps &= ~NFS_CAP_LGOPEN;
2492		}
2493		return;
2494	}
2495	if (!lgp->lo) {
2496		lo = _pnfs_grab_empty_layout(ino, ctx);
2497		if (!lo)
2498			return;
2499		lgp->lo = lo;
2500	} else
2501		lo = lgp->lo;
2502
2503	lseg = pnfs_layout_process(lgp);
2504	if (!IS_ERR(lseg)) {
2505		iomode = lgp->args.range.iomode;
2506		pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2507		pnfs_put_lseg(lseg);
2508	}
2509}
2510
2511void nfs4_lgopen_release(struct nfs4_layoutget *lgp)
2512{
2513	if (lgp != NULL) {
2514		if (lgp->lo) {
2515			pnfs_clear_first_layoutget(lgp->lo);
2516			nfs_layoutget_end(lgp->lo);
2517		}
2518		pnfs_layoutget_free(lgp);
2519	}
2520}
2521
2522struct pnfs_layout_segment *
2523pnfs_layout_process(struct nfs4_layoutget *lgp)
2524{
2525	struct pnfs_layout_hdr *lo = lgp->lo;
2526	struct nfs4_layoutget_res *res = &lgp->res;
2527	struct pnfs_layout_segment *lseg;
2528	struct inode *ino = lo->plh_inode;
2529	LIST_HEAD(free_me);
2530
2531	if (!pnfs_sanity_check_layout_range(&res->range))
2532		return ERR_PTR(-EINVAL);
2533
2534	/* Inject layout blob into I/O device driver */
2535	lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
2536	if (IS_ERR_OR_NULL(lseg)) {
2537		if (!lseg)
2538			lseg = ERR_PTR(-ENOMEM);
2539
2540		dprintk("%s: Could not allocate layout: error %ld\n",
2541		       __func__, PTR_ERR(lseg));
2542		return lseg;
2543	}
2544
2545	pnfs_init_lseg(lo, lseg, &res->range, &res->stateid);
2546
2547	spin_lock(&ino->i_lock);
2548	if (pnfs_layoutgets_blocked(lo)) {
2549		dprintk("%s forget reply due to state\n", __func__);
2550		goto out_forget;
2551	}
2552
2553	if (test_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags) &&
2554	    !pnfs_is_first_layoutget(lo))
2555		goto out_forget;
2556
2557	if (nfs4_stateid_match_other(&lo->plh_stateid, &res->stateid)) {
2558		/* existing state ID, make sure the sequence number matches. */
2559		if (pnfs_layout_stateid_blocked(lo, &res->stateid)) {
2560			if (!pnfs_layout_is_valid(lo))
2561				lo->plh_barrier = 0;
2562			dprintk("%s forget reply due to sequence\n", __func__);
2563			goto out_forget;
2564		}
2565		pnfs_set_layout_stateid(lo, &res->stateid, lgp->cred, false);
2566	} else if (pnfs_layout_is_valid(lo)) {
2567		/*
2568		 * We got an entirely new state ID.  Mark all segments for the
2569		 * inode invalid, and retry the layoutget
2570		 */
2571		struct pnfs_layout_range range = {
2572			.iomode = IOMODE_ANY,
2573			.length = NFS4_MAX_UINT64,
2574		};
2575		pnfs_mark_matching_lsegs_return(lo, &free_me, &range, 0);
2576		goto out_forget;
2577	} else {
2578		/* We have a completely new layout */
2579		pnfs_set_layout_stateid(lo, &res->stateid, lgp->cred, true);
2580	}
2581
2582	pnfs_get_lseg(lseg);
2583	pnfs_layout_insert_lseg(lo, lseg, &free_me);
2584
2585
2586	if (res->return_on_close)
2587		set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
2588
2589	spin_unlock(&ino->i_lock);
2590	pnfs_free_lseg_list(&free_me);
2591	return lseg;
2592
2593out_forget:
2594	spin_unlock(&ino->i_lock);
2595	lseg->pls_layout = lo;
2596	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
2597	return ERR_PTR(-EAGAIN);
2598}
2599
2600/**
2601 * pnfs_mark_matching_lsegs_return - Free or return matching layout segments
2602 * @lo: pointer to layout header
2603 * @tmp_list: list header to be used with pnfs_free_lseg_list()
2604 * @return_range: describe layout segment ranges to be returned
2605 * @seq: stateid seqid to match
2606 *
2607 * This function is mainly intended for use by layoutrecall. It attempts
2608 * to free the layout segment immediately, or else to mark it for return
2609 * as soon as its reference count drops to zero.
2610 *
2611 * Returns
2612 * - 0: a layoutreturn needs to be scheduled.
2613 * - EBUSY: there are layout segment that are still in use.
2614 * - ENOENT: there are no layout segments that need to be returned.
2615 */
2616int
2617pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
2618				struct list_head *tmp_list,
2619				const struct pnfs_layout_range *return_range,
2620				u32 seq)
2621{
2622	struct pnfs_layout_segment *lseg, *next;
2623	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
2624	int remaining = 0;
2625
2626	dprintk("%s:Begin lo %p\n", __func__, lo);
2627
2628	assert_spin_locked(&lo->plh_inode->i_lock);
2629
2630	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
2631		tmp_list = &lo->plh_return_segs;
2632
2633	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
2634		if (pnfs_match_lseg_recall(lseg, return_range, seq)) {
2635			dprintk("%s: marking lseg %p iomode %d "
2636				"offset %llu length %llu\n", __func__,
2637				lseg, lseg->pls_range.iomode,
2638				lseg->pls_range.offset,
2639				lseg->pls_range.length);
2640			if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
2641				tmp_list = &lo->plh_return_segs;
2642			if (mark_lseg_invalid(lseg, tmp_list))
2643				continue;
2644			remaining++;
2645			set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
2646			pnfs_lseg_cancel_io(server, lseg);
2647		}
2648
2649	if (remaining) {
2650		pnfs_set_plh_return_info(lo, return_range->iomode, seq);
2651		return -EBUSY;
2652	}
2653
2654	if (!list_empty(&lo->plh_return_segs)) {
2655		pnfs_set_plh_return_info(lo, return_range->iomode, seq);
2656		return 0;
2657	}
2658
2659	return -ENOENT;
2660}
2661
2662static void
2663pnfs_mark_layout_for_return(struct inode *inode,
2664			    const struct pnfs_layout_range *range)
2665{
2666	struct pnfs_layout_hdr *lo;
2667	bool return_now = false;
2668
2669	spin_lock(&inode->i_lock);
2670	lo = NFS_I(inode)->layout;
2671	if (!pnfs_layout_is_valid(lo)) {
2672		spin_unlock(&inode->i_lock);
2673		return;
2674	}
2675	pnfs_set_plh_return_info(lo, range->iomode, 0);
2676	/*
2677	 * mark all matching lsegs so that we are sure to have no live
2678	 * segments at hand when sending layoutreturn. See pnfs_put_lseg()
2679	 * for how it works.
2680	 */
2681	if (pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs, range, 0) != -EBUSY) {
2682		const struct cred *cred;
2683		nfs4_stateid stateid;
2684		enum pnfs_iomode iomode;
2685
2686		return_now = pnfs_prepare_layoutreturn(lo, &stateid, &cred, &iomode);
2687		spin_unlock(&inode->i_lock);
2688		if (return_now)
2689			pnfs_send_layoutreturn(lo, &stateid, &cred, iomode,
2690					       PNFS_FL_LAYOUTRETURN_ASYNC);
2691	} else {
2692		spin_unlock(&inode->i_lock);
2693		nfs_commit_inode(inode, 0);
2694	}
2695}
2696
2697void pnfs_error_mark_layout_for_return(struct inode *inode,
2698				       struct pnfs_layout_segment *lseg)
2699{
2700	struct pnfs_layout_range range = {
2701		.iomode = lseg->pls_range.iomode,
2702		.offset = 0,
2703		.length = NFS4_MAX_UINT64,
2704	};
2705
2706	pnfs_mark_layout_for_return(inode, &range);
2707}
2708EXPORT_SYMBOL_GPL(pnfs_error_mark_layout_for_return);
2709
2710static bool
2711pnfs_layout_can_be_returned(struct pnfs_layout_hdr *lo)
2712{
2713	return pnfs_layout_is_valid(lo) &&
2714		!test_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags) &&
2715		!test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
2716}
2717
2718static struct pnfs_layout_segment *
2719pnfs_find_first_lseg(struct pnfs_layout_hdr *lo,
2720		     const struct pnfs_layout_range *range,
2721		     enum pnfs_iomode iomode)
2722{
2723	struct pnfs_layout_segment *lseg;
2724
2725	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
2726		if (!test_bit(NFS_LSEG_VALID, &lseg->pls_flags))
2727			continue;
2728		if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
2729			continue;
2730		if (lseg->pls_range.iomode != iomode && iomode != IOMODE_ANY)
2731			continue;
2732		if (pnfs_lseg_range_intersecting(&lseg->pls_range, range))
2733			return lseg;
2734	}
2735	return NULL;
2736}
2737
2738/* Find open file states whose mode matches that of the range */
2739static bool
2740pnfs_should_return_unused_layout(struct pnfs_layout_hdr *lo,
2741				 const struct pnfs_layout_range *range)
2742{
2743	struct list_head *head;
2744	struct nfs_open_context *ctx;
2745	fmode_t mode = 0;
2746
2747	if (!pnfs_layout_can_be_returned(lo) ||
2748	    !pnfs_find_first_lseg(lo, range, range->iomode))
2749		return false;
2750
2751	head = &NFS_I(lo->plh_inode)->open_files;
2752	list_for_each_entry_rcu(ctx, head, list) {
2753		if (ctx->state)
2754			mode |= ctx->state->state & (FMODE_READ|FMODE_WRITE);
2755	}
2756
2757	switch (range->iomode) {
2758	default:
2759		break;
2760	case IOMODE_READ:
2761		mode &= ~FMODE_WRITE;
2762		break;
2763	case IOMODE_RW:
2764		if (pnfs_find_first_lseg(lo, range, IOMODE_READ))
2765			mode &= ~FMODE_READ;
2766	}
2767	return mode == 0;
2768}
2769
2770static int pnfs_layout_return_unused_byserver(struct nfs_server *server,
2771					      void *data)
2772{
2773	const struct pnfs_layout_range *range = data;
2774	const struct cred *cred;
2775	struct pnfs_layout_hdr *lo;
2776	struct inode *inode;
2777	nfs4_stateid stateid;
2778	enum pnfs_iomode iomode;
2779
2780restart:
2781	rcu_read_lock();
2782	list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
2783		inode = lo->plh_inode;
2784		if (!inode || !pnfs_layout_can_be_returned(lo) ||
2785		    test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
2786			continue;
 
2787		spin_lock(&inode->i_lock);
2788		if (!lo->plh_inode ||
2789		    !pnfs_should_return_unused_layout(lo, range)) {
2790			spin_unlock(&inode->i_lock);
2791			continue;
2792		}
2793		pnfs_get_layout_hdr(lo);
2794		pnfs_set_plh_return_info(lo, range->iomode, 0);
2795		if (pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs,
2796						    range, 0) != 0 ||
2797		    !pnfs_prepare_layoutreturn(lo, &stateid, &cred, &iomode)) {
2798			spin_unlock(&inode->i_lock);
2799			rcu_read_unlock();
2800			pnfs_put_layout_hdr(lo);
2801			cond_resched();
2802			goto restart;
2803		}
2804		spin_unlock(&inode->i_lock);
 
 
 
2805		rcu_read_unlock();
2806		pnfs_send_layoutreturn(lo, &stateid, &cred, iomode,
2807				       PNFS_FL_LAYOUTRETURN_ASYNC);
2808		pnfs_put_layout_hdr(lo);
2809		cond_resched();
2810		goto restart;
2811	}
2812	rcu_read_unlock();
2813	return 0;
2814}
2815
2816void
2817pnfs_layout_return_unused_byclid(struct nfs_client *clp,
2818				 enum pnfs_iomode iomode)
2819{
2820	struct pnfs_layout_range range = {
2821		.iomode = iomode,
2822		.offset = 0,
2823		.length = NFS4_MAX_UINT64,
2824	};
2825
2826	nfs_client_for_each_server(clp, pnfs_layout_return_unused_byserver,
2827			&range);
2828}
2829
2830/* Check if we have we have a valid layout but if there isn't an intersection
2831 * between the request and the pgio->pg_lseg, put this pgio->pg_lseg away.
2832 */
2833void
2834pnfs_generic_pg_check_layout(struct nfs_pageio_descriptor *pgio,
2835			     struct nfs_page *req)
2836{
2837	if (pgio->pg_lseg == NULL ||
2838	    (test_bit(NFS_LSEG_VALID, &pgio->pg_lseg->pls_flags) &&
2839	    pnfs_lseg_request_intersecting(pgio->pg_lseg, req)))
2840		return;
2841	pnfs_put_lseg(pgio->pg_lseg);
2842	pgio->pg_lseg = NULL;
2843}
2844EXPORT_SYMBOL_GPL(pnfs_generic_pg_check_layout);
2845
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2846void
2847pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
2848{
2849	u64 rd_size;
2850
2851	pnfs_generic_pg_check_layout(pgio, req);
 
2852	if (pgio->pg_lseg == NULL) {
2853		if (pgio->pg_dreq == NULL)
2854			rd_size = i_size_read(pgio->pg_inode) - req_offset(req);
2855		else
2856			rd_size = nfs_dreq_bytes_left(pgio->pg_dreq,
2857						      req_offset(req));
2858
2859		pgio->pg_lseg =
2860			pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
2861					   req_offset(req), rd_size,
2862					   IOMODE_READ, false,
2863					   nfs_io_gfp_mask());
 
 
2864		if (IS_ERR(pgio->pg_lseg)) {
2865			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2866			pgio->pg_lseg = NULL;
2867			return;
2868		}
2869	}
2870	/* If no lseg, fall back to read through mds */
2871	if (pgio->pg_lseg == NULL)
2872		nfs_pageio_reset_read_mds(pgio);
2873
2874}
2875EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);
2876
2877void
2878pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
2879			   struct nfs_page *req, u64 wb_size)
2880{
2881	pnfs_generic_pg_check_layout(pgio, req);
 
2882	if (pgio->pg_lseg == NULL) {
2883		pgio->pg_lseg =
2884			pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
2885					   req_offset(req), wb_size, IOMODE_RW,
2886					   false, nfs_io_gfp_mask());
 
 
 
2887		if (IS_ERR(pgio->pg_lseg)) {
2888			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2889			pgio->pg_lseg = NULL;
2890			return;
2891		}
2892	}
2893	/* If no lseg, fall back to write through mds */
2894	if (pgio->pg_lseg == NULL)
2895		nfs_pageio_reset_write_mds(pgio);
2896}
2897EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
2898
2899void
2900pnfs_generic_pg_cleanup(struct nfs_pageio_descriptor *desc)
2901{
2902	if (desc->pg_lseg) {
2903		pnfs_put_lseg(desc->pg_lseg);
2904		desc->pg_lseg = NULL;
2905	}
2906}
2907EXPORT_SYMBOL_GPL(pnfs_generic_pg_cleanup);
2908
2909/*
2910 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
2911 * of bytes (maximum @req->wb_bytes) that can be coalesced.
2912 */
2913size_t
2914pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio,
2915		     struct nfs_page *prev, struct nfs_page *req)
2916{
2917	unsigned int size;
2918	u64 seg_end, req_start, seg_left;
2919
2920	size = nfs_generic_pg_test(pgio, prev, req);
2921	if (!size)
2922		return 0;
2923
2924	/*
2925	 * 'size' contains the number of bytes left in the current page (up
2926	 * to the original size asked for in @req->wb_bytes).
2927	 *
2928	 * Calculate how many bytes are left in the layout segment
2929	 * and if there are less bytes than 'size', return that instead.
2930	 *
2931	 * Please also note that 'end_offset' is actually the offset of the
2932	 * first byte that lies outside the pnfs_layout_range. FIXME?
2933	 *
2934	 */
2935	if (pgio->pg_lseg) {
2936		seg_end = pnfs_end_offset(pgio->pg_lseg->pls_range.offset,
2937				     pgio->pg_lseg->pls_range.length);
2938		req_start = req_offset(req);
2939
2940		/* start of request is past the last byte of this segment */
2941		if (req_start >= seg_end)
2942			return 0;
2943
2944		/* adjust 'size' iff there are fewer bytes left in the
2945		 * segment than what nfs_generic_pg_test returned */
2946		seg_left = seg_end - req_start;
2947		if (seg_left < size)
2948			size = (unsigned int)seg_left;
2949	}
2950
2951	return size;
2952}
2953EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
2954
2955int pnfs_write_done_resend_to_mds(struct nfs_pgio_header *hdr)
2956{
2957	struct nfs_pageio_descriptor pgio;
2958
2959	/* Resend all requests through the MDS */
2960	nfs_pageio_init_write(&pgio, hdr->inode, FLUSH_STABLE, true,
2961			      hdr->completion_ops);
 
2962	return nfs_pageio_resend(&pgio, hdr);
2963}
2964EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
2965
2966static void pnfs_ld_handle_write_error(struct nfs_pgio_header *hdr)
2967{
2968
2969	dprintk("pnfs write error = %d\n", hdr->pnfs_error);
2970	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2971	    PNFS_LAYOUTRET_ON_ERROR) {
2972		pnfs_return_layout(hdr->inode);
2973	}
2974	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2975		hdr->task.tk_status = pnfs_write_done_resend_to_mds(hdr);
2976}
2977
2978/*
2979 * Called by non rpc-based layout drivers
2980 */
2981void pnfs_ld_write_done(struct nfs_pgio_header *hdr)
2982{
2983	if (likely(!hdr->pnfs_error)) {
2984		pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
2985				hdr->mds_offset + hdr->res.count);
2986		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
2987	}
2988	trace_nfs4_pnfs_write(hdr, hdr->pnfs_error);
2989	if (unlikely(hdr->pnfs_error))
2990		pnfs_ld_handle_write_error(hdr);
2991	hdr->mds_ops->rpc_release(hdr);
2992}
2993EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
2994
2995static void
2996pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
2997		struct nfs_pgio_header *hdr)
2998{
2999	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
3000
3001	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
3002		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
3003		nfs_pageio_reset_write_mds(desc);
3004		mirror->pg_recoalesce = 1;
3005	}
3006	hdr->completion_ops->completion(hdr);
3007}
3008
3009static enum pnfs_try_status
3010pnfs_try_to_write_data(struct nfs_pgio_header *hdr,
3011			const struct rpc_call_ops *call_ops,
3012			struct pnfs_layout_segment *lseg,
3013			int how)
3014{
3015	struct inode *inode = hdr->inode;
3016	enum pnfs_try_status trypnfs;
3017	struct nfs_server *nfss = NFS_SERVER(inode);
3018
3019	hdr->mds_ops = call_ops;
3020
3021	dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
3022		inode->i_ino, hdr->args.count, hdr->args.offset, how);
3023	trypnfs = nfss->pnfs_curr_ld->write_pagelist(hdr, how);
3024	if (trypnfs != PNFS_NOT_ATTEMPTED)
3025		nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
3026	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
3027	return trypnfs;
3028}
3029
3030static void
3031pnfs_do_write(struct nfs_pageio_descriptor *desc,
3032	      struct nfs_pgio_header *hdr, int how)
3033{
3034	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
3035	struct pnfs_layout_segment *lseg = desc->pg_lseg;
3036	enum pnfs_try_status trypnfs;
3037
3038	trypnfs = pnfs_try_to_write_data(hdr, call_ops, lseg, how);
3039	switch (trypnfs) {
3040	case PNFS_NOT_ATTEMPTED:
3041		pnfs_write_through_mds(desc, hdr);
3042		break;
3043	case PNFS_ATTEMPTED:
3044		break;
3045	case PNFS_TRY_AGAIN:
3046		/* cleanup hdr and prepare to redo pnfs */
3047		if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
3048			struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
3049			list_splice_init(&hdr->pages, &mirror->pg_list);
3050			mirror->pg_recoalesce = 1;
3051		}
3052		hdr->mds_ops->rpc_release(hdr);
3053	}
3054}
3055
3056static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
3057{
3058	pnfs_put_lseg(hdr->lseg);
3059	nfs_pgio_header_free(hdr);
3060}
3061
3062int
3063pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
3064{
3065	struct nfs_pgio_header *hdr;
3066	int ret;
3067
3068	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
3069	if (!hdr) {
3070		desc->pg_error = -ENOMEM;
3071		return desc->pg_error;
3072	}
3073	nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
3074
3075	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
3076	ret = nfs_generic_pgio(desc, hdr);
3077	if (!ret)
3078		pnfs_do_write(desc, hdr, desc->pg_ioflags);
3079
3080	return ret;
3081}
3082EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
3083
3084int pnfs_read_done_resend_to_mds(struct nfs_pgio_header *hdr)
3085{
3086	struct nfs_pageio_descriptor pgio;
3087
3088	/* Resend all requests through the MDS */
3089	nfs_pageio_init_read(&pgio, hdr->inode, true, hdr->completion_ops);
3090	return nfs_pageio_resend(&pgio, hdr);
3091}
3092EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
3093
3094static void pnfs_ld_handle_read_error(struct nfs_pgio_header *hdr)
3095{
3096	dprintk("pnfs read error = %d\n", hdr->pnfs_error);
3097	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
3098	    PNFS_LAYOUTRET_ON_ERROR) {
3099		pnfs_return_layout(hdr->inode);
3100	}
3101	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
3102		hdr->task.tk_status = pnfs_read_done_resend_to_mds(hdr);
3103}
3104
3105/*
3106 * Called by non rpc-based layout drivers
3107 */
3108void pnfs_ld_read_done(struct nfs_pgio_header *hdr)
3109{
3110	if (likely(!hdr->pnfs_error))
3111		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
3112	trace_nfs4_pnfs_read(hdr, hdr->pnfs_error);
3113	if (unlikely(hdr->pnfs_error))
3114		pnfs_ld_handle_read_error(hdr);
3115	hdr->mds_ops->rpc_release(hdr);
3116}
3117EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
3118
3119static void
3120pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
3121		struct nfs_pgio_header *hdr)
3122{
3123	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
3124
3125	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
3126		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
3127		nfs_pageio_reset_read_mds(desc);
3128		mirror->pg_recoalesce = 1;
3129	}
3130	hdr->completion_ops->completion(hdr);
3131}
3132
3133/*
3134 * Call the appropriate parallel I/O subsystem read function.
3135 */
3136static enum pnfs_try_status
3137pnfs_try_to_read_data(struct nfs_pgio_header *hdr,
3138		       const struct rpc_call_ops *call_ops,
3139		       struct pnfs_layout_segment *lseg)
3140{
3141	struct inode *inode = hdr->inode;
3142	struct nfs_server *nfss = NFS_SERVER(inode);
3143	enum pnfs_try_status trypnfs;
3144
3145	hdr->mds_ops = call_ops;
3146
3147	dprintk("%s: Reading ino:%lu %u@%llu\n",
3148		__func__, inode->i_ino, hdr->args.count, hdr->args.offset);
3149
3150	trypnfs = nfss->pnfs_curr_ld->read_pagelist(hdr);
3151	if (trypnfs != PNFS_NOT_ATTEMPTED)
3152		nfs_inc_stats(inode, NFSIOS_PNFS_READ);
3153	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
3154	return trypnfs;
3155}
3156
3157/* Resend all requests through pnfs. */
3158void pnfs_read_resend_pnfs(struct nfs_pgio_header *hdr,
3159			   unsigned int mirror_idx)
3160{
3161	struct nfs_pageio_descriptor pgio;
3162
3163	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
3164		/* Prevent deadlocks with layoutreturn! */
3165		pnfs_put_lseg(hdr->lseg);
3166		hdr->lseg = NULL;
3167
3168		nfs_pageio_init_read(&pgio, hdr->inode, false,
3169					hdr->completion_ops);
3170		pgio.pg_mirror_idx = mirror_idx;
3171		hdr->task.tk_status = nfs_pageio_resend(&pgio, hdr);
3172	}
3173}
3174EXPORT_SYMBOL_GPL(pnfs_read_resend_pnfs);
3175
3176static void
3177pnfs_do_read(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr)
3178{
3179	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
3180	struct pnfs_layout_segment *lseg = desc->pg_lseg;
3181	enum pnfs_try_status trypnfs;
3182
3183	trypnfs = pnfs_try_to_read_data(hdr, call_ops, lseg);
3184	switch (trypnfs) {
3185	case PNFS_NOT_ATTEMPTED:
3186		pnfs_read_through_mds(desc, hdr);
3187		break;
3188	case PNFS_ATTEMPTED:
3189		break;
3190	case PNFS_TRY_AGAIN:
3191		/* cleanup hdr and prepare to redo pnfs */
3192		if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
3193			struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
3194			list_splice_init(&hdr->pages, &mirror->pg_list);
3195			mirror->pg_recoalesce = 1;
3196		}
3197		hdr->mds_ops->rpc_release(hdr);
3198	}
3199}
3200
3201static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
3202{
3203	pnfs_put_lseg(hdr->lseg);
3204	nfs_pgio_header_free(hdr);
3205}
3206
3207int
3208pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
3209{
3210	struct nfs_pgio_header *hdr;
3211	int ret;
3212
3213	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
3214	if (!hdr) {
3215		desc->pg_error = -ENOMEM;
3216		return desc->pg_error;
3217	}
3218	nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
3219	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
3220	ret = nfs_generic_pgio(desc, hdr);
3221	if (!ret)
3222		pnfs_do_read(desc, hdr);
3223	return ret;
3224}
3225EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
3226
3227static void pnfs_clear_layoutcommitting(struct inode *inode)
3228{
3229	unsigned long *bitlock = &NFS_I(inode)->flags;
3230
3231	clear_bit_unlock(NFS_INO_LAYOUTCOMMITTING, bitlock);
3232	smp_mb__after_atomic();
3233	wake_up_bit(bitlock, NFS_INO_LAYOUTCOMMITTING);
3234}
3235
3236/*
3237 * There can be multiple RW segments.
3238 */
3239static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
3240{
3241	struct pnfs_layout_segment *lseg;
3242
3243	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
3244		if (lseg->pls_range.iomode == IOMODE_RW &&
3245		    test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
3246			list_add(&lseg->pls_lc_list, listp);
3247	}
3248}
3249
3250static void pnfs_list_write_lseg_done(struct inode *inode, struct list_head *listp)
3251{
3252	struct pnfs_layout_segment *lseg, *tmp;
3253
3254	/* Matched by references in pnfs_set_layoutcommit */
3255	list_for_each_entry_safe(lseg, tmp, listp, pls_lc_list) {
3256		list_del_init(&lseg->pls_lc_list);
3257		pnfs_put_lseg(lseg);
3258	}
3259
3260	pnfs_clear_layoutcommitting(inode);
3261}
3262
3263void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
3264{
3265	pnfs_layout_io_set_failed(lseg->pls_layout, lseg->pls_range.iomode);
3266}
3267EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
3268
3269void
3270pnfs_set_layoutcommit(struct inode *inode, struct pnfs_layout_segment *lseg,
3271		loff_t end_pos)
3272{
3273	struct nfs_inode *nfsi = NFS_I(inode);
3274	bool mark_as_dirty = false;
3275
3276	spin_lock(&inode->i_lock);
3277	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
3278		nfsi->layout->plh_lwb = end_pos;
3279		mark_as_dirty = true;
3280		dprintk("%s: Set layoutcommit for inode %lu ",
3281			__func__, inode->i_ino);
3282	} else if (end_pos > nfsi->layout->plh_lwb)
3283		nfsi->layout->plh_lwb = end_pos;
3284	if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags)) {
3285		/* references matched in nfs4_layoutcommit_release */
3286		pnfs_get_lseg(lseg);
3287	}
3288	spin_unlock(&inode->i_lock);
3289	dprintk("%s: lseg %p end_pos %llu\n",
3290		__func__, lseg, nfsi->layout->plh_lwb);
3291
3292	/* if pnfs_layoutcommit_inode() runs between inode locks, the next one
3293	 * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */
3294	if (mark_as_dirty)
3295		mark_inode_dirty_sync(inode);
3296}
3297EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
3298
3299void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data)
3300{
3301	struct nfs_server *nfss = NFS_SERVER(data->args.inode);
3302
3303	if (nfss->pnfs_curr_ld->cleanup_layoutcommit)
3304		nfss->pnfs_curr_ld->cleanup_layoutcommit(data);
3305	pnfs_list_write_lseg_done(data->args.inode, &data->lseg_list);
3306}
3307
3308/*
3309 * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
3310 * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
3311 * data to disk to allow the server to recover the data if it crashes.
3312 * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
3313 * is off, and a COMMIT is sent to a data server, or
3314 * if WRITEs to a data server return NFS_DATA_SYNC.
3315 */
3316int
3317pnfs_layoutcommit_inode(struct inode *inode, bool sync)
3318{
3319	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
3320	struct nfs4_layoutcommit_data *data;
3321	struct nfs_inode *nfsi = NFS_I(inode);
3322	loff_t end_pos;
3323	int status;
3324
3325	if (!pnfs_layoutcommit_outstanding(inode))
3326		return 0;
3327
3328	dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
3329
3330	status = -EAGAIN;
3331	if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
3332		if (!sync)
3333			goto out;
3334		status = wait_on_bit_lock_action(&nfsi->flags,
3335				NFS_INO_LAYOUTCOMMITTING,
3336				nfs_wait_bit_killable,
3337				TASK_KILLABLE|TASK_FREEZABLE_UNSAFE);
3338		if (status)
3339			goto out;
3340	}
3341
3342	status = -ENOMEM;
3343	/* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
3344	data = kzalloc(sizeof(*data), nfs_io_gfp_mask());
3345	if (!data)
3346		goto clear_layoutcommitting;
3347
3348	status = 0;
3349	spin_lock(&inode->i_lock);
3350	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
3351		goto out_unlock;
3352
3353	INIT_LIST_HEAD(&data->lseg_list);
3354	pnfs_list_write_lseg(inode, &data->lseg_list);
3355
3356	end_pos = nfsi->layout->plh_lwb;
3357
3358	nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
3359	data->cred = get_cred(nfsi->layout->plh_lc_cred);
3360	spin_unlock(&inode->i_lock);
3361
3362	data->args.inode = inode;
3363	nfs_fattr_init(&data->fattr);
3364	data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
3365	data->res.fattr = &data->fattr;
3366	if (end_pos != 0)
3367		data->args.lastbytewritten = end_pos - 1;
3368	else
3369		data->args.lastbytewritten = U64_MAX;
3370	data->res.server = NFS_SERVER(inode);
3371
3372	if (ld->prepare_layoutcommit) {
3373		status = ld->prepare_layoutcommit(&data->args);
3374		if (status) {
3375			put_cred(data->cred);
3376			spin_lock(&inode->i_lock);
3377			set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags);
3378			if (end_pos > nfsi->layout->plh_lwb)
3379				nfsi->layout->plh_lwb = end_pos;
3380			goto out_unlock;
3381		}
3382	}
3383
3384
3385	status = nfs4_proc_layoutcommit(data, sync);
3386out:
3387	if (status)
3388		mark_inode_dirty_sync(inode);
3389	dprintk("<-- %s status %d\n", __func__, status);
3390	return status;
3391out_unlock:
3392	spin_unlock(&inode->i_lock);
3393	kfree(data);
3394clear_layoutcommitting:
3395	pnfs_clear_layoutcommitting(inode);
3396	goto out;
3397}
3398EXPORT_SYMBOL_GPL(pnfs_layoutcommit_inode);
3399
3400int
3401pnfs_generic_sync(struct inode *inode, bool datasync)
3402{
3403	return pnfs_layoutcommit_inode(inode, true);
3404}
3405EXPORT_SYMBOL_GPL(pnfs_generic_sync);
3406
3407struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
3408{
3409	struct nfs4_threshold *thp;
3410
3411	thp = kzalloc(sizeof(*thp), nfs_io_gfp_mask());
3412	if (!thp) {
3413		dprintk("%s mdsthreshold allocation failed\n", __func__);
3414		return NULL;
3415	}
3416	return thp;
3417}
3418
3419#if IS_ENABLED(CONFIG_NFS_V4_2)
3420int
3421pnfs_report_layoutstat(struct inode *inode, gfp_t gfp_flags)
3422{
3423	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
3424	struct nfs_server *server = NFS_SERVER(inode);
3425	struct nfs_inode *nfsi = NFS_I(inode);
3426	struct nfs42_layoutstat_data *data;
3427	struct pnfs_layout_hdr *hdr;
3428	int status = 0;
3429
3430	if (!pnfs_enabled_sb(server) || !ld->prepare_layoutstats)
3431		goto out;
3432
3433	if (!nfs_server_capable(inode, NFS_CAP_LAYOUTSTATS))
3434		goto out;
3435
3436	if (test_and_set_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags))
3437		goto out;
3438
3439	spin_lock(&inode->i_lock);
3440	if (!NFS_I(inode)->layout) {
3441		spin_unlock(&inode->i_lock);
3442		goto out_clear_layoutstats;
3443	}
3444	hdr = NFS_I(inode)->layout;
3445	pnfs_get_layout_hdr(hdr);
3446	spin_unlock(&inode->i_lock);
3447
3448	data = kzalloc(sizeof(*data), gfp_flags);
3449	if (!data) {
3450		status = -ENOMEM;
3451		goto out_put;
3452	}
3453
3454	data->args.fh = NFS_FH(inode);
3455	data->args.inode = inode;
3456	status = ld->prepare_layoutstats(&data->args);
3457	if (status)
3458		goto out_free;
3459
3460	status = nfs42_proc_layoutstats_generic(NFS_SERVER(inode), data);
3461
3462out:
3463	dprintk("%s returns %d\n", __func__, status);
3464	return status;
3465
3466out_free:
3467	kfree(data);
3468out_put:
3469	pnfs_put_layout_hdr(hdr);
3470out_clear_layoutstats:
3471	smp_mb__before_atomic();
3472	clear_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags);
3473	smp_mb__after_atomic();
3474	goto out;
3475}
3476EXPORT_SYMBOL_GPL(pnfs_report_layoutstat);
3477#endif
3478
3479unsigned int layoutstats_timer;
3480module_param(layoutstats_timer, uint, 0644);
3481EXPORT_SYMBOL_GPL(layoutstats_timer);
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);