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v4.17
   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
  41#define NFSDBG_FACILITY		NFSDBG_PNFS
  42#define PNFS_LAYOUTGET_RETRY_TIMEOUT (120*HZ)
  43
  44/* Locking:
  45 *
  46 * pnfs_spinlock:
  47 *      protects pnfs_modules_tbl.
  48 */
  49static DEFINE_SPINLOCK(pnfs_spinlock);
  50
  51/*
  52 * pnfs_modules_tbl holds all pnfs modules
  53 */
  54static LIST_HEAD(pnfs_modules_tbl);
  55
  56static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo);
  57static void pnfs_free_returned_lsegs(struct pnfs_layout_hdr *lo,
  58		struct list_head *free_me,
  59		const struct pnfs_layout_range *range,
  60		u32 seq);
  61static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
  62		                struct list_head *tmp_list);
  63
  64/* Return the registered pnfs layout driver module matching given id */
  65static struct pnfs_layoutdriver_type *
  66find_pnfs_driver_locked(u32 id)
  67{
  68	struct pnfs_layoutdriver_type *local;
  69
  70	list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid)
  71		if (local->id == id)
  72			goto out;
  73	local = NULL;
  74out:
  75	dprintk("%s: Searching for id %u, found %p\n", __func__, id, local);
  76	return local;
  77}
  78
  79static struct pnfs_layoutdriver_type *
  80find_pnfs_driver(u32 id)
  81{
  82	struct pnfs_layoutdriver_type *local;
  83
  84	spin_lock(&pnfs_spinlock);
  85	local = find_pnfs_driver_locked(id);
  86	if (local != NULL && !try_module_get(local->owner)) {
  87		dprintk("%s: Could not grab reference on module\n", __func__);
  88		local = NULL;
  89	}
  90	spin_unlock(&pnfs_spinlock);
  91	return local;
  92}
  93
 
 
 
 
 
 
 
 
 
 
 
  94void
  95unset_pnfs_layoutdriver(struct nfs_server *nfss)
  96{
  97	if (nfss->pnfs_curr_ld) {
  98		if (nfss->pnfs_curr_ld->clear_layoutdriver)
  99			nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
 100		/* Decrement the MDS count. Purge the deviceid cache if zero */
 101		if (atomic_dec_and_test(&nfss->nfs_client->cl_mds_count))
 102			nfs4_deviceid_purge_client(nfss->nfs_client);
 103		module_put(nfss->pnfs_curr_ld->owner);
 104	}
 105	nfss->pnfs_curr_ld = NULL;
 106}
 107
 108/*
 109 * When the server sends a list of layout types, we choose one in the order
 110 * given in the list below.
 111 *
 112 * FIXME: should this list be configurable in some fashion? module param?
 113 * 	  mount option? something else?
 114 */
 115static const u32 ld_prefs[] = {
 116	LAYOUT_SCSI,
 117	LAYOUT_BLOCK_VOLUME,
 118	LAYOUT_OSD2_OBJECTS,
 119	LAYOUT_FLEX_FILES,
 120	LAYOUT_NFSV4_1_FILES,
 121	0
 122};
 123
 124static int
 125ld_cmp(const void *e1, const void *e2)
 126{
 127	u32 ld1 = *((u32 *)e1);
 128	u32 ld2 = *((u32 *)e2);
 129	int i;
 130
 131	for (i = 0; ld_prefs[i] != 0; i++) {
 132		if (ld1 == ld_prefs[i])
 133			return -1;
 134
 135		if (ld2 == ld_prefs[i])
 136			return 1;
 137	}
 138	return 0;
 139}
 140
 141/*
 142 * Try to set the server's pnfs module to the pnfs layout type specified by id.
 143 * Currently only one pNFS layout driver per filesystem is supported.
 144 *
 145 * @ids array of layout types supported by MDS.
 146 */
 147void
 148set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
 149		      struct nfs_fsinfo *fsinfo)
 150{
 151	struct pnfs_layoutdriver_type *ld_type = NULL;
 152	u32 id;
 153	int i;
 154
 155	if (fsinfo->nlayouttypes == 0)
 156		goto out_no_driver;
 157	if (!(server->nfs_client->cl_exchange_flags &
 158		 (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
 159		printk(KERN_ERR "NFS: %s: cl_exchange_flags 0x%x\n",
 160			__func__, server->nfs_client->cl_exchange_flags);
 161		goto out_no_driver;
 162	}
 163
 164	sort(fsinfo->layouttype, fsinfo->nlayouttypes,
 165		sizeof(*fsinfo->layouttype), ld_cmp, NULL);
 166
 167	for (i = 0; i < fsinfo->nlayouttypes; i++) {
 168		id = fsinfo->layouttype[i];
 169		ld_type = find_pnfs_driver(id);
 170		if (!ld_type) {
 171			request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX,
 172					id);
 173			ld_type = find_pnfs_driver(id);
 174		}
 175		if (ld_type)
 176			break;
 177	}
 178
 179	if (!ld_type) {
 180		dprintk("%s: No pNFS module found!\n", __func__);
 181		goto out_no_driver;
 182	}
 183
 184	server->pnfs_curr_ld = ld_type;
 185	if (ld_type->set_layoutdriver
 186	    && ld_type->set_layoutdriver(server, mntfh)) {
 187		printk(KERN_ERR "NFS: %s: Error initializing pNFS layout "
 188			"driver %u.\n", __func__, id);
 189		module_put(ld_type->owner);
 190		goto out_no_driver;
 191	}
 192	/* Bump the MDS count */
 193	atomic_inc(&server->nfs_client->cl_mds_count);
 194
 195	dprintk("%s: pNFS module for %u set\n", __func__, id);
 196	return;
 197
 198out_no_driver:
 199	dprintk("%s: Using NFSv4 I/O\n", __func__);
 200	server->pnfs_curr_ld = NULL;
 201}
 202
 203int
 204pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 205{
 206	int status = -EINVAL;
 207	struct pnfs_layoutdriver_type *tmp;
 208
 209	if (ld_type->id == 0) {
 210		printk(KERN_ERR "NFS: %s id 0 is reserved\n", __func__);
 211		return status;
 212	}
 213	if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
 214		printk(KERN_ERR "NFS: %s Layout driver must provide "
 215		       "alloc_lseg and free_lseg.\n", __func__);
 216		return status;
 217	}
 218
 219	spin_lock(&pnfs_spinlock);
 220	tmp = find_pnfs_driver_locked(ld_type->id);
 221	if (!tmp) {
 222		list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
 223		status = 0;
 224		dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
 225			ld_type->name);
 226	} else {
 227		printk(KERN_ERR "NFS: %s Module with id %d already loaded!\n",
 228			__func__, ld_type->id);
 229	}
 230	spin_unlock(&pnfs_spinlock);
 231
 232	return status;
 233}
 234EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);
 235
 236void
 237pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 238{
 239	dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
 240	spin_lock(&pnfs_spinlock);
 241	list_del(&ld_type->pnfs_tblid);
 242	spin_unlock(&pnfs_spinlock);
 243}
 244EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
 245
 246/*
 247 * pNFS client layout cache
 248 */
 249
 250/* Need to hold i_lock if caller does not already hold reference */
 251void
 252pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo)
 253{
 254	refcount_inc(&lo->plh_refcount);
 255}
 256
 257static struct pnfs_layout_hdr *
 258pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags)
 259{
 260	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
 261	return ld->alloc_layout_hdr(ino, gfp_flags);
 262}
 263
 264static void
 265pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
 266{
 267	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
 268	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
 269
 270	if (!list_empty(&lo->plh_layouts)) {
 271		struct nfs_client *clp = server->nfs_client;
 272
 273		spin_lock(&clp->cl_lock);
 274		list_del_init(&lo->plh_layouts);
 275		spin_unlock(&clp->cl_lock);
 276	}
 277	put_rpccred(lo->plh_lc_cred);
 278	return ld->free_layout_hdr(lo);
 279}
 280
 281static void
 282pnfs_detach_layout_hdr(struct pnfs_layout_hdr *lo)
 283{
 284	struct nfs_inode *nfsi = NFS_I(lo->plh_inode);
 285	dprintk("%s: freeing layout cache %p\n", __func__, lo);
 286	nfsi->layout = NULL;
 287	/* Reset MDS Threshold I/O counters */
 288	nfsi->write_io = 0;
 289	nfsi->read_io = 0;
 290}
 291
 292void
 293pnfs_put_layout_hdr(struct pnfs_layout_hdr *lo)
 294{
 295	struct inode *inode;
 
 296
 297	if (!lo)
 298		return;
 299	inode = lo->plh_inode;
 300	pnfs_layoutreturn_before_put_layout_hdr(lo);
 301
 302	if (refcount_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
 303		if (!list_empty(&lo->plh_segs))
 304			WARN_ONCE(1, "NFS: BUG unfreed layout segments.\n");
 305		pnfs_detach_layout_hdr(lo);
 
 306		spin_unlock(&inode->i_lock);
 307		pnfs_free_layout_hdr(lo);
 
 
 
 308	}
 309}
 310
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 311static void
 312pnfs_set_plh_return_info(struct pnfs_layout_hdr *lo, enum pnfs_iomode iomode,
 313			 u32 seq)
 314{
 315	if (lo->plh_return_iomode != 0 && lo->plh_return_iomode != iomode)
 316		iomode = IOMODE_ANY;
 317	lo->plh_return_iomode = iomode;
 318	set_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 319	if (seq != 0) {
 320		WARN_ON_ONCE(lo->plh_return_seq != 0 && lo->plh_return_seq != seq);
 
 
 
 
 
 321		lo->plh_return_seq = seq;
 322	}
 323}
 324
 325static void
 326pnfs_clear_layoutreturn_info(struct pnfs_layout_hdr *lo)
 327{
 328	struct pnfs_layout_segment *lseg;
 329	lo->plh_return_iomode = 0;
 330	lo->plh_return_seq = 0;
 331	clear_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 332	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
 333		if (!test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
 334			continue;
 335		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
 336	}
 337}
 338
 339static void pnfs_clear_layoutreturn_waitbit(struct pnfs_layout_hdr *lo)
 340{
 341	clear_bit_unlock(NFS_LAYOUT_RETURN, &lo->plh_flags);
 342	clear_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags);
 343	smp_mb__after_atomic();
 344	wake_up_bit(&lo->plh_flags, NFS_LAYOUT_RETURN);
 345	rpc_wake_up(&NFS_SERVER(lo->plh_inode)->roc_rpcwaitq);
 346}
 347
 348static void
 349pnfs_clear_lseg_state(struct pnfs_layout_segment *lseg,
 350		struct list_head *free_me)
 351{
 352	clear_bit(NFS_LSEG_ROC, &lseg->pls_flags);
 353	clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
 354	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags))
 355		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 356	if (test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
 357		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 358}
 359
 360/*
 361 * Update the seqid of a layout stateid
 
 362 */
 363bool nfs4_refresh_layout_stateid(nfs4_stateid *dst, struct inode *inode)
 
 
 364{
 365	struct pnfs_layout_hdr *lo;
 
 
 
 
 
 366	bool ret = false;
 
 
 367
 368	spin_lock(&inode->i_lock);
 369	lo = NFS_I(inode)->layout;
 370	if (lo && nfs4_stateid_match_other(dst, &lo->plh_stateid)) {
 371		dst->seqid = lo->plh_stateid.seqid;
 372		ret = true;
 
 
 
 
 
 
 
 
 
 
 
 
 373	}
 
 374	spin_unlock(&inode->i_lock);
 
 375	return ret;
 376}
 377
 378/*
 379 * Mark a pnfs_layout_hdr and all associated layout segments as invalid
 380 *
 381 * In order to continue using the pnfs_layout_hdr, a full recovery
 382 * is required.
 383 * Note that caller must hold inode->i_lock.
 384 */
 385int
 386pnfs_mark_layout_stateid_invalid(struct pnfs_layout_hdr *lo,
 387		struct list_head *lseg_list)
 388{
 389	struct pnfs_layout_range range = {
 390		.iomode = IOMODE_ANY,
 391		.offset = 0,
 392		.length = NFS4_MAX_UINT64,
 393	};
 394	struct pnfs_layout_segment *lseg, *next;
 395
 396	set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 397	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 398		pnfs_clear_lseg_state(lseg, lseg_list);
 399	pnfs_clear_layoutreturn_info(lo);
 400	pnfs_free_returned_lsegs(lo, lseg_list, &range, 0);
 
 401	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags) &&
 402	    !test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
 403		pnfs_clear_layoutreturn_waitbit(lo);
 404	return !list_empty(&lo->plh_segs);
 405}
 406
 407static int
 408pnfs_iomode_to_fail_bit(u32 iomode)
 409{
 410	return iomode == IOMODE_RW ?
 411		NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 412}
 413
 414static void
 415pnfs_layout_set_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 416{
 417	lo->plh_retry_timestamp = jiffies;
 418	if (!test_and_set_bit(fail_bit, &lo->plh_flags))
 419		refcount_inc(&lo->plh_refcount);
 420}
 421
 422static void
 423pnfs_layout_clear_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 424{
 425	if (test_and_clear_bit(fail_bit, &lo->plh_flags))
 426		refcount_dec(&lo->plh_refcount);
 427}
 428
 429static void
 430pnfs_layout_io_set_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 431{
 432	struct inode *inode = lo->plh_inode;
 433	struct pnfs_layout_range range = {
 434		.iomode = iomode,
 435		.offset = 0,
 436		.length = NFS4_MAX_UINT64,
 437	};
 438	LIST_HEAD(head);
 439
 440	spin_lock(&inode->i_lock);
 441	pnfs_layout_set_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
 442	pnfs_mark_matching_lsegs_invalid(lo, &head, &range, 0);
 443	spin_unlock(&inode->i_lock);
 444	pnfs_free_lseg_list(&head);
 445	dprintk("%s Setting layout IOMODE_%s fail bit\n", __func__,
 446			iomode == IOMODE_RW ?  "RW" : "READ");
 447}
 448
 449static bool
 450pnfs_layout_io_test_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 451{
 452	unsigned long start, end;
 453	int fail_bit = pnfs_iomode_to_fail_bit(iomode);
 454
 455	if (test_bit(fail_bit, &lo->plh_flags) == 0)
 456		return false;
 457	end = jiffies;
 458	start = end - PNFS_LAYOUTGET_RETRY_TIMEOUT;
 459	if (!time_in_range(lo->plh_retry_timestamp, start, end)) {
 460		/* It is time to retry the failed layoutgets */
 461		pnfs_layout_clear_fail_bit(lo, fail_bit);
 462		return false;
 463	}
 464	return true;
 465}
 466
 467static void
 468pnfs_init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg,
 469		const struct pnfs_layout_range *range,
 470		const nfs4_stateid *stateid)
 471{
 472	INIT_LIST_HEAD(&lseg->pls_list);
 473	INIT_LIST_HEAD(&lseg->pls_lc_list);
 
 474	refcount_set(&lseg->pls_refcount, 1);
 475	set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
 476	lseg->pls_layout = lo;
 477	lseg->pls_range = *range;
 478	lseg->pls_seq = be32_to_cpu(stateid->seqid);
 479}
 480
 481static void pnfs_free_lseg(struct pnfs_layout_segment *lseg)
 482{
 483	if (lseg != NULL) {
 484		struct inode *inode = lseg->pls_layout->plh_inode;
 485		NFS_SERVER(inode)->pnfs_curr_ld->free_lseg(lseg);
 486	}
 487}
 488
 489static void
 490pnfs_layout_remove_lseg(struct pnfs_layout_hdr *lo,
 491		struct pnfs_layout_segment *lseg)
 492{
 493	WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 494	list_del_init(&lseg->pls_list);
 495	/* Matched by pnfs_get_layout_hdr in pnfs_layout_insert_lseg */
 496	refcount_dec(&lo->plh_refcount);
 497	if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
 498		return;
 499	if (list_empty(&lo->plh_segs) &&
 500	    !test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) &&
 501	    !test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
 502		if (atomic_read(&lo->plh_outstanding) == 0)
 503			set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 504		clear_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 505	}
 506}
 507
 508static bool
 509pnfs_cache_lseg_for_layoutreturn(struct pnfs_layout_hdr *lo,
 510		struct pnfs_layout_segment *lseg)
 511{
 512	if (test_and_clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags) &&
 513	    pnfs_layout_is_valid(lo)) {
 514		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
 515		list_move_tail(&lseg->pls_list, &lo->plh_return_segs);
 516		return true;
 517	}
 518	return false;
 519}
 520
 521void
 522pnfs_put_lseg(struct pnfs_layout_segment *lseg)
 523{
 524	struct pnfs_layout_hdr *lo;
 525	struct inode *inode;
 526
 527	if (!lseg)
 528		return;
 529
 530	dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
 531		refcount_read(&lseg->pls_refcount),
 532		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 533
 534	lo = lseg->pls_layout;
 535	inode = lo->plh_inode;
 536
 537	if (refcount_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
 538		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 539			spin_unlock(&inode->i_lock);
 540			return;
 541		}
 542		pnfs_get_layout_hdr(lo);
 543		pnfs_layout_remove_lseg(lo, lseg);
 544		if (pnfs_cache_lseg_for_layoutreturn(lo, lseg))
 545			lseg = NULL;
 546		spin_unlock(&inode->i_lock);
 547		pnfs_free_lseg(lseg);
 548		pnfs_put_layout_hdr(lo);
 549	}
 550}
 551EXPORT_SYMBOL_GPL(pnfs_put_lseg);
 552
 553/*
 554 * is l2 fully contained in l1?
 555 *   start1                             end1
 556 *   [----------------------------------)
 557 *           start2           end2
 558 *           [----------------)
 559 */
 560static bool
 561pnfs_lseg_range_contained(const struct pnfs_layout_range *l1,
 562		 const struct pnfs_layout_range *l2)
 563{
 564	u64 start1 = l1->offset;
 565	u64 end1 = pnfs_end_offset(start1, l1->length);
 566	u64 start2 = l2->offset;
 567	u64 end2 = pnfs_end_offset(start2, l2->length);
 568
 569	return (start1 <= start2) && (end1 >= end2);
 570}
 571
 572static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
 573		struct list_head *tmp_list)
 574{
 575	if (!refcount_dec_and_test(&lseg->pls_refcount))
 576		return false;
 577	pnfs_layout_remove_lseg(lseg->pls_layout, lseg);
 578	list_add(&lseg->pls_list, tmp_list);
 579	return true;
 580}
 581
 582/* Returns 1 if lseg is removed from list, 0 otherwise */
 583static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
 584			     struct list_head *tmp_list)
 585{
 586	int rv = 0;
 587
 588	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 589		/* Remove the reference keeping the lseg in the
 590		 * list.  It will now be removed when all
 591		 * outstanding io is finished.
 592		 */
 593		dprintk("%s: lseg %p ref %d\n", __func__, lseg,
 594			refcount_read(&lseg->pls_refcount));
 595		if (pnfs_lseg_dec_and_remove_zero(lseg, tmp_list))
 596			rv = 1;
 597	}
 598	return rv;
 599}
 600
 601/*
 602 * Compare 2 layout stateid sequence ids, to see which is newer,
 603 * taking into account wraparound issues.
 604 */
 605static bool pnfs_seqid_is_newer(u32 s1, u32 s2)
 606{
 607	return (s32)(s1 - s2) > 0;
 608}
 609
 610static bool
 611pnfs_should_free_range(const struct pnfs_layout_range *lseg_range,
 612		 const struct pnfs_layout_range *recall_range)
 613{
 614	return (recall_range->iomode == IOMODE_ANY ||
 615		lseg_range->iomode == recall_range->iomode) &&
 616	       pnfs_lseg_range_intersecting(lseg_range, recall_range);
 617}
 618
 619static bool
 620pnfs_match_lseg_recall(const struct pnfs_layout_segment *lseg,
 621		const struct pnfs_layout_range *recall_range,
 622		u32 seq)
 623{
 624	if (seq != 0 && pnfs_seqid_is_newer(lseg->pls_seq, seq))
 625		return false;
 626	if (recall_range == NULL)
 627		return true;
 628	return pnfs_should_free_range(&lseg->pls_range, recall_range);
 629}
 630
 631/**
 632 * pnfs_mark_matching_lsegs_invalid - tear down lsegs or mark them for later
 633 * @lo: layout header containing the lsegs
 634 * @tmp_list: list head where doomed lsegs should go
 635 * @recall_range: optional recall range argument to match (may be NULL)
 636 * @seq: only invalidate lsegs obtained prior to this sequence (may be 0)
 637 *
 638 * Walk the list of lsegs in the layout header, and tear down any that should
 639 * be destroyed. If "recall_range" is specified then the segment must match
 640 * that range. If "seq" is non-zero, then only match segments that were handed
 641 * out at or before that sequence.
 642 *
 643 * Returns number of matching invalid lsegs remaining in list after scanning
 644 * it and purging them.
 645 */
 646int
 647pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 648			    struct list_head *tmp_list,
 649			    const struct pnfs_layout_range *recall_range,
 650			    u32 seq)
 651{
 652	struct pnfs_layout_segment *lseg, *next;
 
 653	int remaining = 0;
 654
 655	dprintk("%s:Begin lo %p\n", __func__, lo);
 656
 657	if (list_empty(&lo->plh_segs))
 658		return 0;
 659	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 660		if (pnfs_match_lseg_recall(lseg, recall_range, seq)) {
 661			dprintk("%s: freeing lseg %p iomode %d seq %u "
 662				"offset %llu length %llu\n", __func__,
 663				lseg, lseg->pls_range.iomode, lseg->pls_seq,
 664				lseg->pls_range.offset, lseg->pls_range.length);
 665			if (!mark_lseg_invalid(lseg, tmp_list))
 666				remaining++;
 
 
 667		}
 668	dprintk("%s:Return %i\n", __func__, remaining);
 669	return remaining;
 670}
 671
 672static void
 673pnfs_free_returned_lsegs(struct pnfs_layout_hdr *lo,
 674		struct list_head *free_me,
 675		const struct pnfs_layout_range *range,
 676		u32 seq)
 677{
 678	struct pnfs_layout_segment *lseg, *next;
 679
 680	list_for_each_entry_safe(lseg, next, &lo->plh_return_segs, pls_list) {
 681		if (pnfs_match_lseg_recall(lseg, range, seq))
 682			list_move_tail(&lseg->pls_list, free_me);
 683	}
 684}
 685
 686/* note free_me must contain lsegs from a single layout_hdr */
 687void
 688pnfs_free_lseg_list(struct list_head *free_me)
 689{
 690	struct pnfs_layout_segment *lseg, *tmp;
 691
 692	if (list_empty(free_me))
 693		return;
 694
 695	list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
 696		list_del(&lseg->pls_list);
 697		pnfs_free_lseg(lseg);
 698	}
 699}
 700
 701void
 702pnfs_destroy_layout(struct nfs_inode *nfsi)
 703{
 704	struct pnfs_layout_hdr *lo;
 705	LIST_HEAD(tmp_list);
 706
 707	spin_lock(&nfsi->vfs_inode.i_lock);
 708	lo = nfsi->layout;
 709	if (lo) {
 710		pnfs_get_layout_hdr(lo);
 711		pnfs_mark_layout_stateid_invalid(lo, &tmp_list);
 712		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RO_FAILED);
 713		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RW_FAILED);
 714		spin_unlock(&nfsi->vfs_inode.i_lock);
 715		pnfs_free_lseg_list(&tmp_list);
 716		nfs_commit_inode(&nfsi->vfs_inode, 0);
 717		pnfs_put_layout_hdr(lo);
 718	} else
 719		spin_unlock(&nfsi->vfs_inode.i_lock);
 
 
 
 
 
 
 720}
 721EXPORT_SYMBOL_GPL(pnfs_destroy_layout);
 722
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 723static bool
 724pnfs_layout_add_bulk_destroy_list(struct inode *inode,
 725		struct list_head *layout_list)
 726{
 727	struct pnfs_layout_hdr *lo;
 728	bool ret = false;
 729
 730	spin_lock(&inode->i_lock);
 731	lo = NFS_I(inode)->layout;
 732	if (lo != NULL && list_empty(&lo->plh_bulk_destroy)) {
 733		pnfs_get_layout_hdr(lo);
 734		list_add(&lo->plh_bulk_destroy, layout_list);
 735		ret = true;
 736	}
 737	spin_unlock(&inode->i_lock);
 738	return ret;
 739}
 740
 741/* Caller must hold rcu_read_lock and clp->cl_lock */
 742static int
 743pnfs_layout_bulk_destroy_byserver_locked(struct nfs_client *clp,
 744		struct nfs_server *server,
 745		struct list_head *layout_list)
 
 
 746{
 747	struct pnfs_layout_hdr *lo, *next;
 748	struct inode *inode;
 749
 750	list_for_each_entry_safe(lo, next, &server->layouts, plh_layouts) {
 751		if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags))
 
 
 752			continue;
 753		inode = igrab(lo->plh_inode);
 754		if (inode == NULL)
 755			continue;
 756		list_del_init(&lo->plh_layouts);
 757		if (pnfs_layout_add_bulk_destroy_list(inode, layout_list))
 758			continue;
 759		rcu_read_unlock();
 760		spin_unlock(&clp->cl_lock);
 761		iput(inode);
 
 
 
 
 
 
 
 
 
 762		spin_lock(&clp->cl_lock);
 763		rcu_read_lock();
 764		return -EAGAIN;
 765	}
 766	return 0;
 767}
 768
 769static int
 770pnfs_layout_free_bulk_destroy_list(struct list_head *layout_list,
 771		bool is_bulk_recall)
 772{
 773	struct pnfs_layout_hdr *lo;
 774	struct inode *inode;
 775	LIST_HEAD(lseg_list);
 776	int ret = 0;
 777
 778	while (!list_empty(layout_list)) {
 779		lo = list_entry(layout_list->next, struct pnfs_layout_hdr,
 780				plh_bulk_destroy);
 781		dprintk("%s freeing layout for inode %lu\n", __func__,
 782			lo->plh_inode->i_ino);
 783		inode = lo->plh_inode;
 784
 785		pnfs_layoutcommit_inode(inode, false);
 786
 787		spin_lock(&inode->i_lock);
 788		list_del_init(&lo->plh_bulk_destroy);
 789		if (pnfs_mark_layout_stateid_invalid(lo, &lseg_list)) {
 790			if (is_bulk_recall)
 791				set_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 792			ret = -EAGAIN;
 793		}
 794		spin_unlock(&inode->i_lock);
 795		pnfs_free_lseg_list(&lseg_list);
 796		/* Free all lsegs that are attached to commit buckets */
 797		nfs_commit_inode(inode, 0);
 798		pnfs_put_layout_hdr(lo);
 799		iput(inode);
 800	}
 801	return ret;
 802}
 803
 804int
 805pnfs_destroy_layouts_byfsid(struct nfs_client *clp,
 806		struct nfs_fsid *fsid,
 807		bool is_recall)
 808{
 809	struct nfs_server *server;
 810	LIST_HEAD(layout_list);
 811
 812	spin_lock(&clp->cl_lock);
 813	rcu_read_lock();
 814restart:
 815	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 816		if (memcmp(&server->fsid, fsid, sizeof(*fsid)) != 0)
 817			continue;
 818		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 819				server,
 820				&layout_list) != 0)
 821			goto restart;
 822	}
 823	rcu_read_unlock();
 824	spin_unlock(&clp->cl_lock);
 825
 826	if (list_empty(&layout_list))
 827		return 0;
 828	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 829}
 830
 831int
 832pnfs_destroy_layouts_byclid(struct nfs_client *clp,
 833		bool is_recall)
 834{
 835	struct nfs_server *server;
 836	LIST_HEAD(layout_list);
 837
 838	spin_lock(&clp->cl_lock);
 839	rcu_read_lock();
 840restart:
 841	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 842		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 843					server,
 844					&layout_list) != 0)
 845			goto restart;
 846	}
 847	rcu_read_unlock();
 848	spin_unlock(&clp->cl_lock);
 849
 850	if (list_empty(&layout_list))
 851		return 0;
 852	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 853}
 854
 855/*
 856 * Called by the state manger to remove all layouts established under an
 857 * expired lease.
 858 */
 859void
 860pnfs_destroy_all_layouts(struct nfs_client *clp)
 861{
 862	nfs4_deviceid_mark_client_invalid(clp);
 863	nfs4_deviceid_purge_client(clp);
 864
 865	pnfs_destroy_layouts_byclid(clp, false);
 866}
 867
 
 
 
 
 
 
 
 
 
 
 
 868/* update lo->plh_stateid with new if is more recent */
 869void
 870pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
 871			bool update_barrier)
 872{
 873	u32 oldseq, newseq, new_barrier = 0;
 874
 875	oldseq = be32_to_cpu(lo->plh_stateid.seqid);
 876	newseq = be32_to_cpu(new->seqid);
 877
 878	if (!pnfs_layout_is_valid(lo)) {
 
 879		nfs4_stateid_copy(&lo->plh_stateid, new);
 880		lo->plh_barrier = newseq;
 881		pnfs_clear_layoutreturn_info(lo);
 882		clear_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 883		return;
 884	}
 885	if (pnfs_seqid_is_newer(newseq, oldseq)) {
 
 886		nfs4_stateid_copy(&lo->plh_stateid, new);
 887		/*
 888		 * Because of wraparound, we want to keep the barrier
 889		 * "close" to the current seqids.
 890		 */
 891		new_barrier = newseq - atomic_read(&lo->plh_outstanding);
 892	}
 893	if (update_barrier)
 894		new_barrier = be32_to_cpu(new->seqid);
 895	else if (new_barrier == 0)
 896		return;
 897	if (pnfs_seqid_is_newer(new_barrier, lo->plh_barrier))
 898		lo->plh_barrier = new_barrier;
 
 
 
 
 
 
 899}
 900
 901static bool
 902pnfs_layout_stateid_blocked(const struct pnfs_layout_hdr *lo,
 903		const nfs4_stateid *stateid)
 904{
 905	u32 seqid = be32_to_cpu(stateid->seqid);
 906
 907	return !pnfs_seqid_is_newer(seqid, lo->plh_barrier);
 908}
 909
 910/* lget is set to 1 if called from inside send_layoutget call chain */
 911static bool
 912pnfs_layoutgets_blocked(const struct pnfs_layout_hdr *lo)
 913{
 914	return lo->plh_block_lgets ||
 915		test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 916}
 917
 918/*
 919 * Get layout from server.
 920 *    for now, assume that whole file layouts are requested.
 921 *    arg->offset: 0
 922 *    arg->length: all ones
 923 */
 924static struct pnfs_layout_segment *
 925send_layoutget(struct pnfs_layout_hdr *lo,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 926	   struct nfs_open_context *ctx,
 927	   nfs4_stateid *stateid,
 928	   const struct pnfs_layout_range *range,
 929	   long *timeout, gfp_t gfp_flags)
 930{
 931	struct inode *ino = lo->plh_inode;
 932	struct nfs_server *server = NFS_SERVER(ino);
 
 933	struct nfs4_layoutget *lgp;
 934	loff_t i_size;
 935
 936	dprintk("--> %s\n", __func__);
 937
 938	/*
 939	 * Synchronously retrieve layout information from server and
 940	 * store in lseg. If we race with a concurrent seqid morphing
 941	 * op, then re-send the LAYOUTGET.
 942	 */
 943	lgp = kzalloc(sizeof(*lgp), gfp_flags);
 944	if (lgp == NULL)
 945		return ERR_PTR(-ENOMEM);
 946
 947	i_size = i_size_read(ino);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 948
 949	lgp->args.minlength = PAGE_SIZE;
 950	if (lgp->args.minlength > range->length)
 951		lgp->args.minlength = range->length;
 952	if (range->iomode == IOMODE_READ) {
 953		if (range->offset >= i_size)
 954			lgp->args.minlength = 0;
 955		else if (i_size - range->offset < lgp->args.minlength)
 956			lgp->args.minlength = i_size - range->offset;
 
 
 
 
 957	}
 958	lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
 959	pnfs_copy_range(&lgp->args.range, range);
 960	lgp->args.type = server->pnfs_curr_ld->id;
 961	lgp->args.inode = ino;
 962	lgp->args.ctx = get_nfs_open_context(ctx);
 963	nfs4_stateid_copy(&lgp->args.stateid, stateid);
 964	lgp->gfp_flags = gfp_flags;
 965	lgp->cred = lo->plh_lc_cred;
 
 
 
 
 
 
 966
 967	return nfs4_proc_layoutget(lgp, timeout, gfp_flags);
 
 
 
 968}
 969
 970static void pnfs_clear_layoutcommit(struct inode *inode,
 971		struct list_head *head)
 972{
 973	struct nfs_inode *nfsi = NFS_I(inode);
 974	struct pnfs_layout_segment *lseg, *tmp;
 975
 976	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
 977		return;
 978	list_for_each_entry_safe(lseg, tmp, &nfsi->layout->plh_segs, pls_list) {
 979		if (!test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
 980			continue;
 981		pnfs_lseg_dec_and_remove_zero(lseg, head);
 982	}
 983}
 984
 985void pnfs_layoutreturn_free_lsegs(struct pnfs_layout_hdr *lo,
 986		const nfs4_stateid *arg_stateid,
 987		const struct pnfs_layout_range *range,
 988		const nfs4_stateid *stateid)
 989{
 990	struct inode *inode = lo->plh_inode;
 991	LIST_HEAD(freeme);
 992
 993	spin_lock(&inode->i_lock);
 994	if (!pnfs_layout_is_valid(lo) || !arg_stateid ||
 995	    !nfs4_stateid_match_other(&lo->plh_stateid, arg_stateid))
 996		goto out_unlock;
 997	if (stateid) {
 998		u32 seq = be32_to_cpu(arg_stateid->seqid);
 999
1000		pnfs_mark_matching_lsegs_invalid(lo, &freeme, range, seq);
1001		pnfs_free_returned_lsegs(lo, &freeme, range, seq);
1002		pnfs_set_layout_stateid(lo, stateid, true);
1003	} else
1004		pnfs_mark_layout_stateid_invalid(lo, &freeme);
1005out_unlock:
1006	pnfs_clear_layoutreturn_waitbit(lo);
1007	spin_unlock(&inode->i_lock);
1008	pnfs_free_lseg_list(&freeme);
1009
1010}
1011
1012static bool
1013pnfs_prepare_layoutreturn(struct pnfs_layout_hdr *lo,
1014		nfs4_stateid *stateid,
 
1015		enum pnfs_iomode *iomode)
1016{
1017	/* Serialise LAYOUTGET/LAYOUTRETURN */
1018	if (atomic_read(&lo->plh_outstanding) != 0)
1019		return false;
1020	if (test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
1021		return false;
1022	set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
1023	pnfs_get_layout_hdr(lo);
 
 
1024	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags)) {
1025		if (stateid != NULL) {
1026			nfs4_stateid_copy(stateid, &lo->plh_stateid);
1027			if (lo->plh_return_seq != 0)
1028				stateid->seqid = cpu_to_be32(lo->plh_return_seq);
1029		}
1030		if (iomode != NULL)
1031			*iomode = lo->plh_return_iomode;
1032		pnfs_clear_layoutreturn_info(lo);
1033		return true;
1034	}
1035	if (stateid != NULL)
1036		nfs4_stateid_copy(stateid, &lo->plh_stateid);
1037	if (iomode != NULL)
1038		*iomode = IOMODE_ANY;
 
1039	return true;
1040}
1041
1042static void
1043pnfs_init_layoutreturn_args(struct nfs4_layoutreturn_args *args,
1044		struct pnfs_layout_hdr *lo,
1045		const nfs4_stateid *stateid,
1046		enum pnfs_iomode iomode)
1047{
1048	struct inode *inode = lo->plh_inode;
1049
1050	args->layout_type = NFS_SERVER(inode)->pnfs_curr_ld->id;
1051	args->inode = inode;
1052	args->range.iomode = iomode;
1053	args->range.offset = 0;
1054	args->range.length = NFS4_MAX_UINT64;
1055	args->layout = lo;
1056	nfs4_stateid_copy(&args->stateid, stateid);
1057}
1058
1059static int
1060pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo, const nfs4_stateid *stateid,
1061		       enum pnfs_iomode iomode, bool sync)
 
 
 
1062{
1063	struct inode *ino = lo->plh_inode;
1064	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1065	struct nfs4_layoutreturn *lrp;
 
1066	int status = 0;
1067
1068	lrp = kzalloc(sizeof(*lrp), GFP_NOFS);
 
1069	if (unlikely(lrp == NULL)) {
1070		status = -ENOMEM;
1071		spin_lock(&ino->i_lock);
1072		pnfs_clear_layoutreturn_waitbit(lo);
1073		spin_unlock(&ino->i_lock);
 
1074		pnfs_put_layout_hdr(lo);
1075		goto out;
1076	}
1077
1078	pnfs_init_layoutreturn_args(&lrp->args, lo, stateid, iomode);
1079	lrp->args.ld_private = &lrp->ld_private;
1080	lrp->clp = NFS_SERVER(ino)->nfs_client;
1081	lrp->cred = lo->plh_lc_cred;
1082	if (ld->prepare_layoutreturn)
1083		ld->prepare_layoutreturn(&lrp->args);
1084
1085	status = nfs4_proc_layoutreturn(lrp, sync);
1086out:
1087	dprintk("<-- %s status: %d\n", __func__, status);
1088	return status;
1089}
1090
 
 
 
 
 
 
 
 
 
 
 
 
 
1091/* Return true if layoutreturn is needed */
1092static bool
1093pnfs_layout_need_return(struct pnfs_layout_hdr *lo)
1094{
1095	struct pnfs_layout_segment *s;
1096
1097	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1098		return false;
1099
1100	/* Defer layoutreturn until all lsegs are done */
1101	list_for_each_entry(s, &lo->plh_segs, pls_list) {
1102		if (test_bit(NFS_LSEG_LAYOUTRETURN, &s->pls_flags))
1103			return false;
1104	}
1105
1106	return true;
1107}
1108
1109static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo)
1110{
1111	struct inode *inode= lo->plh_inode;
1112
1113	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1114		return;
1115	spin_lock(&inode->i_lock);
1116	if (pnfs_layout_need_return(lo)) {
 
1117		nfs4_stateid stateid;
1118		enum pnfs_iomode iomode;
1119		bool send;
1120
1121		send = pnfs_prepare_layoutreturn(lo, &stateid, &iomode);
1122		spin_unlock(&inode->i_lock);
1123		if (send) {
1124			/* Send an async layoutreturn so we dont deadlock */
1125			pnfs_send_layoutreturn(lo, &stateid, iomode, false);
1126		}
1127	} else
1128		spin_unlock(&inode->i_lock);
1129}
1130
1131/*
1132 * Initiates a LAYOUTRETURN(FILE), and removes the pnfs_layout_hdr
1133 * when the layout segment list is empty.
1134 *
1135 * Note that a pnfs_layout_hdr can exist with an empty layout segment
1136 * list when LAYOUTGET has failed, or when LAYOUTGET succeeded, but the
1137 * deviceid is marked invalid.
1138 */
1139int
1140_pnfs_return_layout(struct inode *ino)
1141{
1142	struct pnfs_layout_hdr *lo = NULL;
1143	struct nfs_inode *nfsi = NFS_I(ino);
 
 
 
 
 
1144	LIST_HEAD(tmp_list);
 
1145	nfs4_stateid stateid;
1146	int status = 0;
1147	bool send;
1148
1149	dprintk("NFS: %s for inode %lu\n", __func__, ino->i_ino);
1150
1151	spin_lock(&ino->i_lock);
1152	lo = nfsi->layout;
1153	if (!lo) {
1154		spin_unlock(&ino->i_lock);
1155		dprintk("NFS: %s no layout to return\n", __func__);
1156		goto out;
1157	}
1158	/* Reference matched in nfs4_layoutreturn_release */
1159	pnfs_get_layout_hdr(lo);
1160	/* Is there an outstanding layoutreturn ? */
1161	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1162		spin_unlock(&ino->i_lock);
1163		if (wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1164					TASK_UNINTERRUPTIBLE))
1165			goto out_put_layout_hdr;
1166		spin_lock(&ino->i_lock);
1167	}
 
1168	pnfs_clear_layoutcommit(ino, &tmp_list);
1169	pnfs_mark_matching_lsegs_invalid(lo, &tmp_list, NULL, 0);
1170
1171	if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) {
1172		struct pnfs_layout_range range = {
1173			.iomode		= IOMODE_ANY,
1174			.offset		= 0,
1175			.length		= NFS4_MAX_UINT64,
1176		};
1177		NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo, &range);
1178	}
1179
1180	/* Don't send a LAYOUTRETURN if list was initially empty */
1181	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags)) {
 
1182		spin_unlock(&ino->i_lock);
1183		dprintk("NFS: %s no layout segments to return\n", __func__);
1184		goto out_put_layout_hdr;
1185	}
1186
1187	send = pnfs_prepare_layoutreturn(lo, &stateid, NULL);
1188	spin_unlock(&ino->i_lock);
1189	if (send)
1190		status = pnfs_send_layoutreturn(lo, &stateid, IOMODE_ANY, true);
 
 
1191out_put_layout_hdr:
1192	pnfs_free_lseg_list(&tmp_list);
1193	pnfs_put_layout_hdr(lo);
1194out:
1195	dprintk("<-- %s status: %d\n", __func__, status);
1196	return status;
1197}
1198
1199int
1200pnfs_commit_and_return_layout(struct inode *inode)
1201{
1202	struct pnfs_layout_hdr *lo;
1203	int ret;
1204
1205	spin_lock(&inode->i_lock);
1206	lo = NFS_I(inode)->layout;
1207	if (lo == NULL) {
1208		spin_unlock(&inode->i_lock);
1209		return 0;
1210	}
1211	pnfs_get_layout_hdr(lo);
1212	/* Block new layoutgets and read/write to ds */
1213	lo->plh_block_lgets++;
1214	spin_unlock(&inode->i_lock);
1215	filemap_fdatawait(inode->i_mapping);
1216	ret = pnfs_layoutcommit_inode(inode, true);
1217	if (ret == 0)
1218		ret = _pnfs_return_layout(inode);
1219	spin_lock(&inode->i_lock);
1220	lo->plh_block_lgets--;
1221	spin_unlock(&inode->i_lock);
1222	pnfs_put_layout_hdr(lo);
1223	return ret;
1224}
1225
1226bool pnfs_roc(struct inode *ino,
1227		struct nfs4_layoutreturn_args *args,
1228		struct nfs4_layoutreturn_res *res,
1229		const struct rpc_cred *cred)
1230{
1231	struct nfs_inode *nfsi = NFS_I(ino);
1232	struct nfs_open_context *ctx;
1233	struct nfs4_state *state;
1234	struct pnfs_layout_hdr *lo;
1235	struct pnfs_layout_segment *lseg, *next;
 
1236	nfs4_stateid stateid;
1237	enum pnfs_iomode iomode = 0;
1238	bool layoutreturn = false, roc = false;
1239	bool skip_read = false;
1240
1241	if (!nfs_have_layout(ino))
1242		return false;
1243retry:
 
1244	spin_lock(&ino->i_lock);
1245	lo = nfsi->layout;
1246	if (!lo || !pnfs_layout_is_valid(lo) ||
1247	    test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1248		lo = NULL;
1249		goto out_noroc;
1250	}
1251	pnfs_get_layout_hdr(lo);
1252	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1253		spin_unlock(&ino->i_lock);
 
1254		wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1255				TASK_UNINTERRUPTIBLE);
1256		pnfs_put_layout_hdr(lo);
1257		goto retry;
1258	}
1259
1260	/* no roc if we hold a delegation */
1261	if (nfs4_check_delegation(ino, FMODE_READ)) {
1262		if (nfs4_check_delegation(ino, FMODE_WRITE))
1263			goto out_noroc;
1264		skip_read = true;
1265	}
1266
1267	list_for_each_entry(ctx, &nfsi->open_files, list) {
1268		state = ctx->state;
1269		if (state == NULL)
1270			continue;
1271		/* Don't return layout if there is open file state */
1272		if (state->state & FMODE_WRITE)
1273			goto out_noroc;
1274		if (state->state & FMODE_READ)
1275			skip_read = true;
1276	}
1277
1278
1279	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list) {
1280		if (skip_read && lseg->pls_range.iomode == IOMODE_READ)
1281			continue;
1282		/* If we are sending layoutreturn, invalidate all valid lsegs */
1283		if (!test_and_clear_bit(NFS_LSEG_ROC, &lseg->pls_flags))
1284			continue;
1285		/*
1286		 * Note: mark lseg for return so pnfs_layout_remove_lseg
1287		 * doesn't invalidate the layout for us.
1288		 */
1289		set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
1290		if (!mark_lseg_invalid(lseg, &lo->plh_return_segs))
1291			continue;
1292		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
1293	}
1294
1295	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1296		goto out_noroc;
1297
1298	/* ROC in two conditions:
1299	 * 1. there are ROC lsegs
1300	 * 2. we don't send layoutreturn
1301	 */
1302	/* lo ref dropped in pnfs_roc_release() */
1303	layoutreturn = pnfs_prepare_layoutreturn(lo, &stateid, &iomode);
1304	/* If the creds don't match, we can't compound the layoutreturn */
1305	if (!layoutreturn || cred != lo->plh_lc_cred)
1306		goto out_noroc;
1307
1308	roc = layoutreturn;
1309	pnfs_init_layoutreturn_args(args, lo, &stateid, iomode);
1310	res->lrs_present = 0;
1311	layoutreturn = false;
 
1312
1313out_noroc:
1314	spin_unlock(&ino->i_lock);
 
1315	pnfs_layoutcommit_inode(ino, true);
1316	if (roc) {
1317		struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1318		if (ld->prepare_layoutreturn)
1319			ld->prepare_layoutreturn(args);
1320		pnfs_put_layout_hdr(lo);
1321		return true;
1322	}
1323	if (layoutreturn)
1324		pnfs_send_layoutreturn(lo, &stateid, iomode, true);
1325	pnfs_put_layout_hdr(lo);
1326	return false;
1327}
1328
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1329void pnfs_roc_release(struct nfs4_layoutreturn_args *args,
1330		struct nfs4_layoutreturn_res *res,
1331		int ret)
1332{
1333	struct pnfs_layout_hdr *lo = args->layout;
1334	const nfs4_stateid *arg_stateid = NULL;
1335	const nfs4_stateid *res_stateid = NULL;
1336	struct nfs4_xdr_opaque_data *ld_private = args->ld_private;
1337
1338	if (ret == 0) {
1339		arg_stateid = &args->stateid;
 
 
 
 
 
 
 
 
1340		if (res->lrs_present)
1341			res_stateid = &res->stateid;
 
 
 
 
1342	}
1343	pnfs_layoutreturn_free_lsegs(lo, arg_stateid, &args->range,
1344			res_stateid);
1345	if (ld_private && ld_private->ops && ld_private->ops->free)
1346		ld_private->ops->free(ld_private);
1347	pnfs_put_layout_hdr(lo);
1348	trace_nfs4_layoutreturn_on_close(args->inode, 0);
1349}
1350
1351bool pnfs_wait_on_layoutreturn(struct inode *ino, struct rpc_task *task)
1352{
1353	struct nfs_inode *nfsi = NFS_I(ino);
1354        struct pnfs_layout_hdr *lo;
1355        bool sleep = false;
1356
1357	/* we might not have grabbed lo reference. so need to check under
1358	 * i_lock */
1359        spin_lock(&ino->i_lock);
1360        lo = nfsi->layout;
1361        if (lo && test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
1362                rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
1363                sleep = true;
1364	}
1365        spin_unlock(&ino->i_lock);
1366        return sleep;
1367}
1368
1369/*
1370 * Compare two layout segments for sorting into layout cache.
1371 * We want to preferentially return RW over RO layouts, so ensure those
1372 * are seen first.
1373 */
1374static s64
1375pnfs_lseg_range_cmp(const struct pnfs_layout_range *l1,
1376	   const struct pnfs_layout_range *l2)
1377{
1378	s64 d;
1379
1380	/* high offset > low offset */
1381	d = l1->offset - l2->offset;
1382	if (d)
1383		return d;
1384
1385	/* short length > long length */
1386	d = l2->length - l1->length;
1387	if (d)
1388		return d;
1389
1390	/* read > read/write */
1391	return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
1392}
1393
1394static bool
1395pnfs_lseg_range_is_after(const struct pnfs_layout_range *l1,
1396		const struct pnfs_layout_range *l2)
1397{
1398	return pnfs_lseg_range_cmp(l1, l2) > 0;
1399}
1400
1401static bool
1402pnfs_lseg_no_merge(struct pnfs_layout_segment *lseg,
1403		struct pnfs_layout_segment *old)
1404{
1405	return false;
1406}
1407
1408void
1409pnfs_generic_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1410		   struct pnfs_layout_segment *lseg,
1411		   bool (*is_after)(const struct pnfs_layout_range *,
1412			   const struct pnfs_layout_range *),
1413		   bool (*do_merge)(struct pnfs_layout_segment *,
1414			   struct pnfs_layout_segment *),
1415		   struct list_head *free_me)
1416{
1417	struct pnfs_layout_segment *lp, *tmp;
1418
1419	dprintk("%s:Begin\n", __func__);
1420
1421	list_for_each_entry_safe(lp, tmp, &lo->plh_segs, pls_list) {
1422		if (test_bit(NFS_LSEG_VALID, &lp->pls_flags) == 0)
1423			continue;
1424		if (do_merge(lseg, lp)) {
1425			mark_lseg_invalid(lp, free_me);
1426			continue;
1427		}
1428		if (is_after(&lseg->pls_range, &lp->pls_range))
1429			continue;
1430		list_add_tail(&lseg->pls_list, &lp->pls_list);
1431		dprintk("%s: inserted lseg %p "
1432			"iomode %d offset %llu length %llu before "
1433			"lp %p iomode %d offset %llu length %llu\n",
1434			__func__, lseg, lseg->pls_range.iomode,
1435			lseg->pls_range.offset, lseg->pls_range.length,
1436			lp, lp->pls_range.iomode, lp->pls_range.offset,
1437			lp->pls_range.length);
1438		goto out;
1439	}
1440	list_add_tail(&lseg->pls_list, &lo->plh_segs);
1441	dprintk("%s: inserted lseg %p "
1442		"iomode %d offset %llu length %llu at tail\n",
1443		__func__, lseg, lseg->pls_range.iomode,
1444		lseg->pls_range.offset, lseg->pls_range.length);
1445out:
1446	pnfs_get_layout_hdr(lo);
1447
1448	dprintk("%s:Return\n", __func__);
1449}
1450EXPORT_SYMBOL_GPL(pnfs_generic_layout_insert_lseg);
1451
1452static void
1453pnfs_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1454		   struct pnfs_layout_segment *lseg,
1455		   struct list_head *free_me)
1456{
1457	struct inode *inode = lo->plh_inode;
1458	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
1459
1460	if (ld->add_lseg != NULL)
1461		ld->add_lseg(lo, lseg, free_me);
1462	else
1463		pnfs_generic_layout_insert_lseg(lo, lseg,
1464				pnfs_lseg_range_is_after,
1465				pnfs_lseg_no_merge,
1466				free_me);
1467}
1468
1469static struct pnfs_layout_hdr *
1470alloc_init_layout_hdr(struct inode *ino,
1471		      struct nfs_open_context *ctx,
1472		      gfp_t gfp_flags)
1473{
1474	struct pnfs_layout_hdr *lo;
1475
1476	lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
1477	if (!lo)
1478		return NULL;
1479	refcount_set(&lo->plh_refcount, 1);
1480	INIT_LIST_HEAD(&lo->plh_layouts);
1481	INIT_LIST_HEAD(&lo->plh_segs);
1482	INIT_LIST_HEAD(&lo->plh_return_segs);
1483	INIT_LIST_HEAD(&lo->plh_bulk_destroy);
1484	lo->plh_inode = ino;
1485	lo->plh_lc_cred = get_rpccred(ctx->cred);
1486	lo->plh_flags |= 1 << NFS_LAYOUT_INVALID_STID;
1487	return lo;
1488}
1489
1490static struct pnfs_layout_hdr *
1491pnfs_find_alloc_layout(struct inode *ino,
1492		       struct nfs_open_context *ctx,
1493		       gfp_t gfp_flags)
1494	__releases(&ino->i_lock)
1495	__acquires(&ino->i_lock)
1496{
1497	struct nfs_inode *nfsi = NFS_I(ino);
1498	struct pnfs_layout_hdr *new = NULL;
1499
1500	dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
1501
1502	if (nfsi->layout != NULL)
1503		goto out_existing;
1504	spin_unlock(&ino->i_lock);
1505	new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
1506	spin_lock(&ino->i_lock);
1507
1508	if (likely(nfsi->layout == NULL)) {	/* Won the race? */
1509		nfsi->layout = new;
1510		return new;
1511	} else if (new != NULL)
1512		pnfs_free_layout_hdr(new);
1513out_existing:
1514	pnfs_get_layout_hdr(nfsi->layout);
1515	return nfsi->layout;
1516}
1517
1518/*
1519 * iomode matching rules:
1520 * iomode	lseg	strict match
1521 *                      iomode
1522 * -----	-----	------ -----
1523 * ANY		READ	N/A    true
1524 * ANY		RW	N/A    true
1525 * RW		READ	N/A    false
1526 * RW		RW	N/A    true
1527 * READ		READ	N/A    true
1528 * READ		RW	true   false
1529 * READ		RW	false  true
1530 */
1531static bool
1532pnfs_lseg_range_match(const struct pnfs_layout_range *ls_range,
1533		 const struct pnfs_layout_range *range,
1534		 bool strict_iomode)
1535{
1536	struct pnfs_layout_range range1;
1537
1538	if ((range->iomode == IOMODE_RW &&
1539	     ls_range->iomode != IOMODE_RW) ||
1540	    (range->iomode != ls_range->iomode &&
1541	     strict_iomode) ||
1542	    !pnfs_lseg_range_intersecting(ls_range, range))
1543		return 0;
1544
1545	/* range1 covers only the first byte in the range */
1546	range1 = *range;
1547	range1.length = 1;
1548	return pnfs_lseg_range_contained(ls_range, &range1);
1549}
1550
1551/*
1552 * lookup range in layout
1553 */
1554static struct pnfs_layout_segment *
1555pnfs_find_lseg(struct pnfs_layout_hdr *lo,
1556		struct pnfs_layout_range *range,
1557		bool strict_iomode)
1558{
1559	struct pnfs_layout_segment *lseg, *ret = NULL;
1560
1561	dprintk("%s:Begin\n", __func__);
1562
1563	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
1564		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
1565		    !test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags) &&
1566		    pnfs_lseg_range_match(&lseg->pls_range, range,
1567					  strict_iomode)) {
1568			ret = pnfs_get_lseg(lseg);
1569			break;
1570		}
1571	}
1572
1573	dprintk("%s:Return lseg %p ref %d\n",
1574		__func__, ret, ret ? refcount_read(&ret->pls_refcount) : 0);
1575	return ret;
1576}
1577
1578/*
1579 * Use mdsthreshold hints set at each OPEN to determine if I/O should go
1580 * to the MDS or over pNFS
1581 *
1582 * The nfs_inode read_io and write_io fields are cumulative counters reset
1583 * when there are no layout segments. Note that in pnfs_update_layout iomode
1584 * is set to IOMODE_READ for a READ request, and set to IOMODE_RW for a
1585 * WRITE request.
1586 *
1587 * A return of true means use MDS I/O.
1588 *
1589 * From rfc 5661:
1590 * If a file's size is smaller than the file size threshold, data accesses
1591 * SHOULD be sent to the metadata server.  If an I/O request has a length that
1592 * is below the I/O size threshold, the I/O SHOULD be sent to the metadata
1593 * server.  If both file size and I/O size are provided, the client SHOULD
1594 * reach or exceed  both thresholds before sending its read or write
1595 * requests to the data server.
1596 */
1597static bool pnfs_within_mdsthreshold(struct nfs_open_context *ctx,
1598				     struct inode *ino, int iomode)
1599{
1600	struct nfs4_threshold *t = ctx->mdsthreshold;
1601	struct nfs_inode *nfsi = NFS_I(ino);
1602	loff_t fsize = i_size_read(ino);
1603	bool size = false, size_set = false, io = false, io_set = false, ret = false;
1604
1605	if (t == NULL)
1606		return ret;
1607
1608	dprintk("%s bm=0x%x rd_sz=%llu wr_sz=%llu rd_io=%llu wr_io=%llu\n",
1609		__func__, t->bm, t->rd_sz, t->wr_sz, t->rd_io_sz, t->wr_io_sz);
1610
1611	switch (iomode) {
1612	case IOMODE_READ:
1613		if (t->bm & THRESHOLD_RD) {
1614			dprintk("%s fsize %llu\n", __func__, fsize);
1615			size_set = true;
1616			if (fsize < t->rd_sz)
1617				size = true;
1618		}
1619		if (t->bm & THRESHOLD_RD_IO) {
1620			dprintk("%s nfsi->read_io %llu\n", __func__,
1621				nfsi->read_io);
1622			io_set = true;
1623			if (nfsi->read_io < t->rd_io_sz)
1624				io = true;
1625		}
1626		break;
1627	case IOMODE_RW:
1628		if (t->bm & THRESHOLD_WR) {
1629			dprintk("%s fsize %llu\n", __func__, fsize);
1630			size_set = true;
1631			if (fsize < t->wr_sz)
1632				size = true;
1633		}
1634		if (t->bm & THRESHOLD_WR_IO) {
1635			dprintk("%s nfsi->write_io %llu\n", __func__,
1636				nfsi->write_io);
1637			io_set = true;
1638			if (nfsi->write_io < t->wr_io_sz)
1639				io = true;
1640		}
1641		break;
1642	}
1643	if (size_set && io_set) {
1644		if (size && io)
1645			ret = true;
1646	} else if (size || io)
1647		ret = true;
1648
1649	dprintk("<-- %s size %d io %d ret %d\n", __func__, size, io, ret);
1650	return ret;
1651}
1652
1653static bool pnfs_prepare_to_retry_layoutget(struct pnfs_layout_hdr *lo)
1654{
1655	/*
1656	 * send layoutcommit as it can hold up layoutreturn due to lseg
1657	 * reference
1658	 */
1659	pnfs_layoutcommit_inode(lo->plh_inode, false);
1660	return !wait_on_bit_action(&lo->plh_flags, NFS_LAYOUT_RETURN,
1661				   nfs_wait_bit_killable,
1662				   TASK_UNINTERRUPTIBLE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1663}
1664
1665static void pnfs_clear_first_layoutget(struct pnfs_layout_hdr *lo)
1666{
1667	unsigned long *bitlock = &lo->plh_flags;
1668
1669	clear_bit_unlock(NFS_LAYOUT_FIRST_LAYOUTGET, bitlock);
1670	smp_mb__after_atomic();
1671	wake_up_bit(bitlock, NFS_LAYOUT_FIRST_LAYOUTGET);
1672}
1673
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1674/*
1675 * Layout segment is retreived from the server if not cached.
1676 * The appropriate layout segment is referenced and returned to the caller.
1677 */
1678struct pnfs_layout_segment *
1679pnfs_update_layout(struct inode *ino,
1680		   struct nfs_open_context *ctx,
1681		   loff_t pos,
1682		   u64 count,
1683		   enum pnfs_iomode iomode,
1684		   bool strict_iomode,
1685		   gfp_t gfp_flags)
1686{
1687	struct pnfs_layout_range arg = {
1688		.iomode = iomode,
1689		.offset = pos,
1690		.length = count,
1691	};
1692	unsigned pg_offset;
1693	struct nfs_server *server = NFS_SERVER(ino);
1694	struct nfs_client *clp = server->nfs_client;
1695	struct pnfs_layout_hdr *lo = NULL;
1696	struct pnfs_layout_segment *lseg = NULL;
 
1697	nfs4_stateid stateid;
1698	long timeout = 0;
1699	unsigned long giveup = jiffies + (clp->cl_lease_time << 1);
1700	bool first;
1701
1702	if (!pnfs_enabled_sb(NFS_SERVER(ino))) {
1703		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1704				 PNFS_UPDATE_LAYOUT_NO_PNFS);
1705		goto out;
1706	}
1707
1708	if (iomode == IOMODE_READ && i_size_read(ino) == 0) {
1709		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1710				 PNFS_UPDATE_LAYOUT_RD_ZEROLEN);
1711		goto out;
1712	}
1713
1714	if (pnfs_within_mdsthreshold(ctx, ino, iomode)) {
1715		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1716				 PNFS_UPDATE_LAYOUT_MDSTHRESH);
1717		goto out;
1718	}
1719
1720lookup_again:
1721	nfs4_client_recover_expired_lease(clp);
 
 
1722	first = false;
1723	spin_lock(&ino->i_lock);
1724	lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
1725	if (lo == NULL) {
1726		spin_unlock(&ino->i_lock);
 
1727		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1728				 PNFS_UPDATE_LAYOUT_NOMEM);
1729		goto out;
1730	}
1731
1732	/* Do we even need to bother with this? */
1733	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1734		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1735				 PNFS_UPDATE_LAYOUT_BULK_RECALL);
1736		dprintk("%s matches recall, use MDS\n", __func__);
1737		goto out_unlock;
1738	}
1739
1740	/* if LAYOUTGET already failed once we don't try again */
1741	if (pnfs_layout_io_test_failed(lo, iomode)) {
1742		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1743				 PNFS_UPDATE_LAYOUT_IO_TEST_FAIL);
1744		goto out_unlock;
1745	}
1746
1747	lseg = pnfs_find_lseg(lo, &arg, strict_iomode);
1748	if (lseg) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1749		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1750				PNFS_UPDATE_LAYOUT_FOUND_CACHED);
1751		goto out_unlock;
1752	}
1753
1754	if (!nfs4_valid_open_stateid(ctx->state)) {
 
1755		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1756				PNFS_UPDATE_LAYOUT_INVALID_OPEN);
1757		goto out_unlock;
1758	}
1759
1760	/*
1761	 * Choose a stateid for the LAYOUTGET. If we don't have a layout
1762	 * stateid, or it has been invalidated, then we must use the open
1763	 * stateid.
1764	 */
1765	if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags)) {
 
1766
1767		/*
1768		 * The first layoutget for the file. Need to serialize per
1769		 * RFC 5661 Errata 3208.
1770		 */
1771		if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET,
1772				     &lo->plh_flags)) {
1773			spin_unlock(&ino->i_lock);
1774			wait_on_bit(&lo->plh_flags, NFS_LAYOUT_FIRST_LAYOUTGET,
1775				    TASK_UNINTERRUPTIBLE);
 
 
 
1776			pnfs_put_layout_hdr(lo);
1777			dprintk("%s retrying\n", __func__);
1778			goto lookup_again;
1779		}
1780
 
1781		first = true;
1782		if (nfs4_select_rw_stateid(ctx->state,
1783					iomode == IOMODE_RW ? FMODE_WRITE : FMODE_READ,
1784					NULL, &stateid, NULL) != 0) {
 
 
1785			trace_pnfs_update_layout(ino, pos, count,
1786					iomode, lo, lseg,
1787					PNFS_UPDATE_LAYOUT_INVALID_OPEN);
1788			goto out_unlock;
1789		}
1790	} else {
1791		nfs4_stateid_copy(&stateid, &lo->plh_stateid);
1792	}
1793
1794	/*
1795	 * Because we free lsegs before sending LAYOUTRETURN, we need to wait
1796	 * for LAYOUTRETURN even if first is true.
1797	 */
1798	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
1799		spin_unlock(&ino->i_lock);
1800		dprintk("%s wait for layoutreturn\n", __func__);
1801		if (pnfs_prepare_to_retry_layoutget(lo)) {
1802			if (first)
1803				pnfs_clear_first_layoutget(lo);
1804			pnfs_put_layout_hdr(lo);
1805			dprintk("%s retrying\n", __func__);
1806			trace_pnfs_update_layout(ino, pos, count, iomode, lo,
1807					lseg, PNFS_UPDATE_LAYOUT_RETRY);
1808			goto lookup_again;
1809		}
1810		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1811				PNFS_UPDATE_LAYOUT_RETURN);
1812		goto out_put_layout_hdr;
1813	}
1814
1815	if (pnfs_layoutgets_blocked(lo)) {
1816		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1817				PNFS_UPDATE_LAYOUT_BLOCKED);
1818		goto out_unlock;
1819	}
1820	atomic_inc(&lo->plh_outstanding);
1821	spin_unlock(&ino->i_lock);
1822
1823	if (list_empty(&lo->plh_layouts)) {
1824		/* The lo must be on the clp list if there is any
1825		 * chance of a CB_LAYOUTRECALL(FILE) coming in.
1826		 */
1827		spin_lock(&clp->cl_lock);
1828		if (list_empty(&lo->plh_layouts))
1829			list_add_tail(&lo->plh_layouts, &server->layouts);
1830		spin_unlock(&clp->cl_lock);
1831	}
1832
1833	pg_offset = arg.offset & ~PAGE_MASK;
1834	if (pg_offset) {
1835		arg.offset -= pg_offset;
1836		arg.length += pg_offset;
1837	}
1838	if (arg.length != NFS4_MAX_UINT64)
1839		arg.length = PAGE_ALIGN(arg.length);
1840
1841	lseg = send_layoutget(lo, ctx, &stateid, &arg, &timeout, gfp_flags);
 
 
 
 
 
 
 
 
 
 
 
 
1842	trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1843				 PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET);
1844	atomic_dec(&lo->plh_outstanding);
1845	if (IS_ERR(lseg)) {
1846		switch(PTR_ERR(lseg)) {
1847		case -EBUSY:
1848			if (time_after(jiffies, giveup))
1849				lseg = NULL;
1850			break;
1851		case -ERECALLCONFLICT:
1852			/* Huh? We hold no layouts, how is there a recall? */
1853			if (first) {
1854				lseg = NULL;
1855				break;
1856			}
1857			/* Destroy the existing layout and start over */
1858			if (time_after(jiffies, giveup))
1859				pnfs_destroy_layout(NFS_I(ino));
1860			/* Fallthrough */
1861		case -EAGAIN:
1862			break;
 
 
 
 
 
 
1863		default:
1864			if (!nfs_error_is_fatal(PTR_ERR(lseg))) {
1865				pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
1866				lseg = NULL;
1867			}
1868			goto out_put_layout_hdr;
1869		}
1870		if (lseg) {
1871			if (first)
1872				pnfs_clear_first_layoutget(lo);
1873			trace_pnfs_update_layout(ino, pos, count,
1874				iomode, lo, lseg, PNFS_UPDATE_LAYOUT_RETRY);
1875			pnfs_put_layout_hdr(lo);
1876			goto lookup_again;
1877		}
1878	} else {
1879		pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
1880	}
1881
1882out_put_layout_hdr:
1883	if (first)
1884		pnfs_clear_first_layoutget(lo);
 
 
1885	pnfs_put_layout_hdr(lo);
1886out:
1887	dprintk("%s: inode %s/%llu pNFS layout segment %s for "
1888			"(%s, offset: %llu, length: %llu)\n",
1889			__func__, ino->i_sb->s_id,
1890			(unsigned long long)NFS_FILEID(ino),
1891			IS_ERR_OR_NULL(lseg) ? "not found" : "found",
1892			iomode==IOMODE_RW ?  "read/write" : "read-only",
1893			(unsigned long long)pos,
1894			(unsigned long long)count);
1895	return lseg;
1896out_unlock:
1897	spin_unlock(&ino->i_lock);
1898	goto out_put_layout_hdr;
1899}
1900EXPORT_SYMBOL_GPL(pnfs_update_layout);
1901
1902static bool
1903pnfs_sanity_check_layout_range(struct pnfs_layout_range *range)
1904{
1905	switch (range->iomode) {
1906	case IOMODE_READ:
1907	case IOMODE_RW:
1908		break;
1909	default:
1910		return false;
1911	}
1912	if (range->offset == NFS4_MAX_UINT64)
1913		return false;
1914	if (range->length == 0)
1915		return false;
1916	if (range->length != NFS4_MAX_UINT64 &&
1917	    range->length > NFS4_MAX_UINT64 - range->offset)
1918		return false;
1919	return true;
1920}
1921
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1922struct pnfs_layout_segment *
1923pnfs_layout_process(struct nfs4_layoutget *lgp)
1924{
1925	struct pnfs_layout_hdr *lo = NFS_I(lgp->args.inode)->layout;
1926	struct nfs4_layoutget_res *res = &lgp->res;
1927	struct pnfs_layout_segment *lseg;
1928	struct inode *ino = lo->plh_inode;
1929	LIST_HEAD(free_me);
1930
1931	if (!pnfs_sanity_check_layout_range(&res->range))
1932		return ERR_PTR(-EINVAL);
1933
1934	/* Inject layout blob into I/O device driver */
1935	lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
1936	if (IS_ERR_OR_NULL(lseg)) {
1937		if (!lseg)
1938			lseg = ERR_PTR(-ENOMEM);
1939
1940		dprintk("%s: Could not allocate layout: error %ld\n",
1941		       __func__, PTR_ERR(lseg));
1942		return lseg;
1943	}
1944
1945	pnfs_init_lseg(lo, lseg, &res->range, &res->stateid);
1946
1947	spin_lock(&ino->i_lock);
1948	if (pnfs_layoutgets_blocked(lo)) {
1949		dprintk("%s forget reply due to state\n", __func__);
1950		goto out_forget;
1951	}
1952
1953	if (!pnfs_layout_is_valid(lo)) {
1954		/* We have a completely new layout */
1955		pnfs_set_layout_stateid(lo, &res->stateid, true);
1956	} else if (nfs4_stateid_match_other(&lo->plh_stateid, &res->stateid)) {
 
1957		/* existing state ID, make sure the sequence number matches. */
1958		if (pnfs_layout_stateid_blocked(lo, &res->stateid)) {
 
 
1959			dprintk("%s forget reply due to sequence\n", __func__);
1960			goto out_forget;
1961		}
1962		pnfs_set_layout_stateid(lo, &res->stateid, false);
1963	} else {
1964		/*
1965		 * We got an entirely new state ID.  Mark all segments for the
1966		 * inode invalid, and retry the layoutget
1967		 */
1968		pnfs_mark_layout_stateid_invalid(lo, &free_me);
 
 
 
 
1969		goto out_forget;
 
 
 
1970	}
1971
1972	pnfs_get_lseg(lseg);
1973	pnfs_layout_insert_lseg(lo, lseg, &free_me);
1974
1975
1976	if (res->return_on_close)
1977		set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
1978
1979	spin_unlock(&ino->i_lock);
1980	pnfs_free_lseg_list(&free_me);
1981	return lseg;
1982
1983out_forget:
1984	spin_unlock(&ino->i_lock);
1985	lseg->pls_layout = lo;
1986	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
1987	if (!pnfs_layout_is_valid(lo))
1988		nfs_commit_inode(ino, 0);
1989	return ERR_PTR(-EAGAIN);
1990}
1991
1992/**
1993 * pnfs_mark_matching_lsegs_return - Free or return matching layout segments
1994 * @lo: pointer to layout header
1995 * @tmp_list: list header to be used with pnfs_free_lseg_list()
1996 * @return_range: describe layout segment ranges to be returned
 
1997 *
1998 * This function is mainly intended for use by layoutrecall. It attempts
1999 * to free the layout segment immediately, or else to mark it for return
2000 * as soon as its reference count drops to zero.
 
 
 
 
 
2001 */
2002int
2003pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
2004				struct list_head *tmp_list,
2005				const struct pnfs_layout_range *return_range,
2006				u32 seq)
2007{
2008	struct pnfs_layout_segment *lseg, *next;
 
2009	int remaining = 0;
2010
2011	dprintk("%s:Begin lo %p\n", __func__, lo);
2012
2013	if (list_empty(&lo->plh_segs))
2014		return 0;
2015
2016	assert_spin_locked(&lo->plh_inode->i_lock);
2017
 
 
 
2018	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
2019		if (pnfs_match_lseg_recall(lseg, return_range, seq)) {
2020			dprintk("%s: marking lseg %p iomode %d "
2021				"offset %llu length %llu\n", __func__,
2022				lseg, lseg->pls_range.iomode,
2023				lseg->pls_range.offset,
2024				lseg->pls_range.length);
 
 
2025			if (mark_lseg_invalid(lseg, tmp_list))
2026				continue;
2027			remaining++;
2028			set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
 
2029		}
2030
2031	if (remaining)
 
 
 
 
 
2032		pnfs_set_plh_return_info(lo, return_range->iomode, seq);
 
 
2033
2034	return remaining;
2035}
2036
2037void pnfs_error_mark_layout_for_return(struct inode *inode,
2038				       struct pnfs_layout_segment *lseg)
 
2039{
2040	struct pnfs_layout_hdr *lo = NFS_I(inode)->layout;
2041	struct pnfs_layout_range range = {
2042		.iomode = lseg->pls_range.iomode,
2043		.offset = 0,
2044		.length = NFS4_MAX_UINT64,
2045	};
2046	bool return_now = false;
2047
2048	spin_lock(&inode->i_lock);
 
2049	if (!pnfs_layout_is_valid(lo)) {
2050		spin_unlock(&inode->i_lock);
2051		return;
2052	}
2053	pnfs_set_plh_return_info(lo, range.iomode, 0);
2054	/*
2055	 * mark all matching lsegs so that we are sure to have no live
2056	 * segments at hand when sending layoutreturn. See pnfs_put_lseg()
2057	 * for how it works.
2058	 */
2059	if (!pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs, &range, 0)) {
 
2060		nfs4_stateid stateid;
2061		enum pnfs_iomode iomode;
2062
2063		return_now = pnfs_prepare_layoutreturn(lo, &stateid, &iomode);
2064		spin_unlock(&inode->i_lock);
2065		if (return_now)
2066			pnfs_send_layoutreturn(lo, &stateid, iomode, false);
2067	} else {
2068		spin_unlock(&inode->i_lock);
2069		nfs_commit_inode(inode, 0);
2070	}
2071}
 
 
 
 
 
 
 
 
 
 
 
 
2072EXPORT_SYMBOL_GPL(pnfs_error_mark_layout_for_return);
2073
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2074void
2075pnfs_generic_pg_check_layout(struct nfs_pageio_descriptor *pgio)
2076{
2077	if (pgio->pg_lseg == NULL ||
2078	    test_bit(NFS_LSEG_VALID, &pgio->pg_lseg->pls_flags))
2079		return;
2080	pnfs_put_lseg(pgio->pg_lseg);
2081	pgio->pg_lseg = NULL;
2082}
2083EXPORT_SYMBOL_GPL(pnfs_generic_pg_check_layout);
2084
2085/*
2086 * Check for any intersection between the request and the pgio->pg_lseg,
2087 * and if none, put this pgio->pg_lseg away.
2088 */
2089static void
2090pnfs_generic_pg_check_range(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
2091{
2092	if (pgio->pg_lseg && !pnfs_lseg_request_intersecting(pgio->pg_lseg, req)) {
2093		pnfs_put_lseg(pgio->pg_lseg);
2094		pgio->pg_lseg = NULL;
2095	}
2096}
 
2097
2098void
2099pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
2100{
2101	u64 rd_size = req->wb_bytes;
2102
2103	pnfs_generic_pg_check_layout(pgio);
2104	pnfs_generic_pg_check_range(pgio, req);
2105	if (pgio->pg_lseg == NULL) {
2106		if (pgio->pg_dreq == NULL)
2107			rd_size = i_size_read(pgio->pg_inode) - req_offset(req);
2108		else
2109			rd_size = nfs_dreq_bytes_left(pgio->pg_dreq);
2110
2111		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
2112						   req->wb_context,
2113						   req_offset(req),
2114						   rd_size,
2115						   IOMODE_READ,
2116						   false,
2117						   GFP_KERNEL);
2118		if (IS_ERR(pgio->pg_lseg)) {
2119			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2120			pgio->pg_lseg = NULL;
2121			return;
2122		}
2123	}
2124	/* If no lseg, fall back to read through mds */
2125	if (pgio->pg_lseg == NULL)
2126		nfs_pageio_reset_read_mds(pgio);
2127
2128}
2129EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);
2130
2131void
2132pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
2133			   struct nfs_page *req, u64 wb_size)
2134{
2135	pnfs_generic_pg_check_layout(pgio);
2136	pnfs_generic_pg_check_range(pgio, req);
2137	if (pgio->pg_lseg == NULL) {
2138		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
2139						   req->wb_context,
2140						   req_offset(req),
2141						   wb_size,
2142						   IOMODE_RW,
2143						   false,
2144						   GFP_NOFS);
2145		if (IS_ERR(pgio->pg_lseg)) {
2146			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2147			pgio->pg_lseg = NULL;
2148			return;
2149		}
2150	}
2151	/* If no lseg, fall back to write through mds */
2152	if (pgio->pg_lseg == NULL)
2153		nfs_pageio_reset_write_mds(pgio);
2154}
2155EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
2156
2157void
2158pnfs_generic_pg_cleanup(struct nfs_pageio_descriptor *desc)
2159{
2160	if (desc->pg_lseg) {
2161		pnfs_put_lseg(desc->pg_lseg);
2162		desc->pg_lseg = NULL;
2163	}
2164}
2165EXPORT_SYMBOL_GPL(pnfs_generic_pg_cleanup);
2166
2167/*
2168 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
2169 * of bytes (maximum @req->wb_bytes) that can be coalesced.
2170 */
2171size_t
2172pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio,
2173		     struct nfs_page *prev, struct nfs_page *req)
2174{
2175	unsigned int size;
2176	u64 seg_end, req_start, seg_left;
2177
2178	size = nfs_generic_pg_test(pgio, prev, req);
2179	if (!size)
2180		return 0;
2181
2182	/*
2183	 * 'size' contains the number of bytes left in the current page (up
2184	 * to the original size asked for in @req->wb_bytes).
2185	 *
2186	 * Calculate how many bytes are left in the layout segment
2187	 * and if there are less bytes than 'size', return that instead.
2188	 *
2189	 * Please also note that 'end_offset' is actually the offset of the
2190	 * first byte that lies outside the pnfs_layout_range. FIXME?
2191	 *
2192	 */
2193	if (pgio->pg_lseg) {
2194		seg_end = pnfs_end_offset(pgio->pg_lseg->pls_range.offset,
2195				     pgio->pg_lseg->pls_range.length);
2196		req_start = req_offset(req);
2197
2198		/* start of request is past the last byte of this segment */
2199		if (req_start >= seg_end)
2200			return 0;
2201
2202		/* adjust 'size' iff there are fewer bytes left in the
2203		 * segment than what nfs_generic_pg_test returned */
2204		seg_left = seg_end - req_start;
2205		if (seg_left < size)
2206			size = (unsigned int)seg_left;
2207	}
2208
2209	return size;
2210}
2211EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
2212
2213int pnfs_write_done_resend_to_mds(struct nfs_pgio_header *hdr)
2214{
2215	struct nfs_pageio_descriptor pgio;
2216
2217	/* Resend all requests through the MDS */
2218	nfs_pageio_init_write(&pgio, hdr->inode, FLUSH_STABLE, true,
2219			      hdr->completion_ops);
2220	set_bit(NFS_CONTEXT_RESEND_WRITES, &hdr->args.context->flags);
2221	return nfs_pageio_resend(&pgio, hdr);
2222}
2223EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
2224
2225static void pnfs_ld_handle_write_error(struct nfs_pgio_header *hdr)
2226{
2227
2228	dprintk("pnfs write error = %d\n", hdr->pnfs_error);
2229	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2230	    PNFS_LAYOUTRET_ON_ERROR) {
2231		pnfs_return_layout(hdr->inode);
2232	}
2233	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2234		hdr->task.tk_status = pnfs_write_done_resend_to_mds(hdr);
2235}
2236
2237/*
2238 * Called by non rpc-based layout drivers
2239 */
2240void pnfs_ld_write_done(struct nfs_pgio_header *hdr)
2241{
2242	if (likely(!hdr->pnfs_error)) {
2243		pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
2244				hdr->mds_offset + hdr->res.count);
2245		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
2246	}
2247	trace_nfs4_pnfs_write(hdr, hdr->pnfs_error);
2248	if (unlikely(hdr->pnfs_error))
2249		pnfs_ld_handle_write_error(hdr);
2250	hdr->mds_ops->rpc_release(hdr);
2251}
2252EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
2253
2254static void
2255pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
2256		struct nfs_pgio_header *hdr)
2257{
2258	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2259
2260	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2261		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
2262		nfs_pageio_reset_write_mds(desc);
2263		mirror->pg_recoalesce = 1;
2264	}
2265	hdr->completion_ops->completion(hdr);
2266}
2267
2268static enum pnfs_try_status
2269pnfs_try_to_write_data(struct nfs_pgio_header *hdr,
2270			const struct rpc_call_ops *call_ops,
2271			struct pnfs_layout_segment *lseg,
2272			int how)
2273{
2274	struct inode *inode = hdr->inode;
2275	enum pnfs_try_status trypnfs;
2276	struct nfs_server *nfss = NFS_SERVER(inode);
2277
2278	hdr->mds_ops = call_ops;
2279
2280	dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
2281		inode->i_ino, hdr->args.count, hdr->args.offset, how);
2282	trypnfs = nfss->pnfs_curr_ld->write_pagelist(hdr, how);
2283	if (trypnfs != PNFS_NOT_ATTEMPTED)
2284		nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
2285	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
2286	return trypnfs;
2287}
2288
2289static void
2290pnfs_do_write(struct nfs_pageio_descriptor *desc,
2291	      struct nfs_pgio_header *hdr, int how)
2292{
2293	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
2294	struct pnfs_layout_segment *lseg = desc->pg_lseg;
2295	enum pnfs_try_status trypnfs;
2296
2297	trypnfs = pnfs_try_to_write_data(hdr, call_ops, lseg, how);
2298	switch (trypnfs) {
2299	case PNFS_NOT_ATTEMPTED:
2300		pnfs_write_through_mds(desc, hdr);
 
2301	case PNFS_ATTEMPTED:
2302		break;
2303	case PNFS_TRY_AGAIN:
2304		/* cleanup hdr and prepare to redo pnfs */
2305		if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2306			struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2307			list_splice_init(&hdr->pages, &mirror->pg_list);
2308			mirror->pg_recoalesce = 1;
2309		}
2310		hdr->mds_ops->rpc_release(hdr);
2311	}
2312}
2313
2314static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
2315{
2316	pnfs_put_lseg(hdr->lseg);
2317	nfs_pgio_header_free(hdr);
2318}
2319
2320int
2321pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
2322{
2323	struct nfs_pgio_header *hdr;
2324	int ret;
2325
2326	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
2327	if (!hdr) {
2328		desc->pg_error = -ENOMEM;
2329		return desc->pg_error;
2330	}
2331	nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
2332
2333	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
2334	ret = nfs_generic_pgio(desc, hdr);
2335	if (!ret)
2336		pnfs_do_write(desc, hdr, desc->pg_ioflags);
2337
2338	return ret;
2339}
2340EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
2341
2342int pnfs_read_done_resend_to_mds(struct nfs_pgio_header *hdr)
2343{
2344	struct nfs_pageio_descriptor pgio;
2345
2346	/* Resend all requests through the MDS */
2347	nfs_pageio_init_read(&pgio, hdr->inode, true, hdr->completion_ops);
2348	return nfs_pageio_resend(&pgio, hdr);
2349}
2350EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
2351
2352static void pnfs_ld_handle_read_error(struct nfs_pgio_header *hdr)
2353{
2354	dprintk("pnfs read error = %d\n", hdr->pnfs_error);
2355	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2356	    PNFS_LAYOUTRET_ON_ERROR) {
2357		pnfs_return_layout(hdr->inode);
2358	}
2359	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2360		hdr->task.tk_status = pnfs_read_done_resend_to_mds(hdr);
2361}
2362
2363/*
2364 * Called by non rpc-based layout drivers
2365 */
2366void pnfs_ld_read_done(struct nfs_pgio_header *hdr)
2367{
2368	if (likely(!hdr->pnfs_error))
2369		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
2370	trace_nfs4_pnfs_read(hdr, hdr->pnfs_error);
2371	if (unlikely(hdr->pnfs_error))
2372		pnfs_ld_handle_read_error(hdr);
2373	hdr->mds_ops->rpc_release(hdr);
2374}
2375EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
2376
2377static void
2378pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
2379		struct nfs_pgio_header *hdr)
2380{
2381	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2382
2383	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2384		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
2385		nfs_pageio_reset_read_mds(desc);
2386		mirror->pg_recoalesce = 1;
2387	}
2388	hdr->completion_ops->completion(hdr);
2389}
2390
2391/*
2392 * Call the appropriate parallel I/O subsystem read function.
2393 */
2394static enum pnfs_try_status
2395pnfs_try_to_read_data(struct nfs_pgio_header *hdr,
2396		       const struct rpc_call_ops *call_ops,
2397		       struct pnfs_layout_segment *lseg)
2398{
2399	struct inode *inode = hdr->inode;
2400	struct nfs_server *nfss = NFS_SERVER(inode);
2401	enum pnfs_try_status trypnfs;
2402
2403	hdr->mds_ops = call_ops;
2404
2405	dprintk("%s: Reading ino:%lu %u@%llu\n",
2406		__func__, inode->i_ino, hdr->args.count, hdr->args.offset);
2407
2408	trypnfs = nfss->pnfs_curr_ld->read_pagelist(hdr);
2409	if (trypnfs != PNFS_NOT_ATTEMPTED)
2410		nfs_inc_stats(inode, NFSIOS_PNFS_READ);
2411	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
2412	return trypnfs;
2413}
2414
2415/* Resend all requests through pnfs. */
2416void pnfs_read_resend_pnfs(struct nfs_pgio_header *hdr)
 
2417{
2418	struct nfs_pageio_descriptor pgio;
2419
2420	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2421		/* Prevent deadlocks with layoutreturn! */
2422		pnfs_put_lseg(hdr->lseg);
2423		hdr->lseg = NULL;
2424
2425		nfs_pageio_init_read(&pgio, hdr->inode, false,
2426					hdr->completion_ops);
 
2427		hdr->task.tk_status = nfs_pageio_resend(&pgio, hdr);
2428	}
2429}
2430EXPORT_SYMBOL_GPL(pnfs_read_resend_pnfs);
2431
2432static void
2433pnfs_do_read(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr)
2434{
2435	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
2436	struct pnfs_layout_segment *lseg = desc->pg_lseg;
2437	enum pnfs_try_status trypnfs;
2438
2439	trypnfs = pnfs_try_to_read_data(hdr, call_ops, lseg);
2440	switch (trypnfs) {
2441	case PNFS_NOT_ATTEMPTED:
2442		pnfs_read_through_mds(desc, hdr);
 
2443	case PNFS_ATTEMPTED:
2444		break;
2445	case PNFS_TRY_AGAIN:
2446		/* cleanup hdr and prepare to redo pnfs */
2447		if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2448			struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2449			list_splice_init(&hdr->pages, &mirror->pg_list);
2450			mirror->pg_recoalesce = 1;
2451		}
2452		hdr->mds_ops->rpc_release(hdr);
2453	}
2454}
2455
2456static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
2457{
2458	pnfs_put_lseg(hdr->lseg);
2459	nfs_pgio_header_free(hdr);
2460}
2461
2462int
2463pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
2464{
2465	struct nfs_pgio_header *hdr;
2466	int ret;
2467
2468	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
2469	if (!hdr) {
2470		desc->pg_error = -ENOMEM;
2471		return desc->pg_error;
2472	}
2473	nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
2474	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
2475	ret = nfs_generic_pgio(desc, hdr);
2476	if (!ret)
2477		pnfs_do_read(desc, hdr);
2478	return ret;
2479}
2480EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
2481
2482static void pnfs_clear_layoutcommitting(struct inode *inode)
2483{
2484	unsigned long *bitlock = &NFS_I(inode)->flags;
2485
2486	clear_bit_unlock(NFS_INO_LAYOUTCOMMITTING, bitlock);
2487	smp_mb__after_atomic();
2488	wake_up_bit(bitlock, NFS_INO_LAYOUTCOMMITTING);
2489}
2490
2491/*
2492 * There can be multiple RW segments.
2493 */
2494static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
2495{
2496	struct pnfs_layout_segment *lseg;
2497
2498	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
2499		if (lseg->pls_range.iomode == IOMODE_RW &&
2500		    test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
2501			list_add(&lseg->pls_lc_list, listp);
2502	}
2503}
2504
2505static void pnfs_list_write_lseg_done(struct inode *inode, struct list_head *listp)
2506{
2507	struct pnfs_layout_segment *lseg, *tmp;
2508
2509	/* Matched by references in pnfs_set_layoutcommit */
2510	list_for_each_entry_safe(lseg, tmp, listp, pls_lc_list) {
2511		list_del_init(&lseg->pls_lc_list);
2512		pnfs_put_lseg(lseg);
2513	}
2514
2515	pnfs_clear_layoutcommitting(inode);
2516}
2517
2518void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
2519{
2520	pnfs_layout_io_set_failed(lseg->pls_layout, lseg->pls_range.iomode);
2521}
2522EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
2523
2524void
2525pnfs_set_layoutcommit(struct inode *inode, struct pnfs_layout_segment *lseg,
2526		loff_t end_pos)
2527{
2528	struct nfs_inode *nfsi = NFS_I(inode);
2529	bool mark_as_dirty = false;
2530
2531	spin_lock(&inode->i_lock);
2532	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
2533		nfsi->layout->plh_lwb = end_pos;
2534		mark_as_dirty = true;
2535		dprintk("%s: Set layoutcommit for inode %lu ",
2536			__func__, inode->i_ino);
2537	} else if (end_pos > nfsi->layout->plh_lwb)
2538		nfsi->layout->plh_lwb = end_pos;
2539	if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags)) {
2540		/* references matched in nfs4_layoutcommit_release */
2541		pnfs_get_lseg(lseg);
2542	}
2543	spin_unlock(&inode->i_lock);
2544	dprintk("%s: lseg %p end_pos %llu\n",
2545		__func__, lseg, nfsi->layout->plh_lwb);
2546
2547	/* if pnfs_layoutcommit_inode() runs between inode locks, the next one
2548	 * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */
2549	if (mark_as_dirty)
2550		mark_inode_dirty_sync(inode);
2551}
2552EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
2553
2554void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data)
2555{
2556	struct nfs_server *nfss = NFS_SERVER(data->args.inode);
2557
2558	if (nfss->pnfs_curr_ld->cleanup_layoutcommit)
2559		nfss->pnfs_curr_ld->cleanup_layoutcommit(data);
2560	pnfs_list_write_lseg_done(data->args.inode, &data->lseg_list);
2561}
2562
2563/*
2564 * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
2565 * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
2566 * data to disk to allow the server to recover the data if it crashes.
2567 * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
2568 * is off, and a COMMIT is sent to a data server, or
2569 * if WRITEs to a data server return NFS_DATA_SYNC.
2570 */
2571int
2572pnfs_layoutcommit_inode(struct inode *inode, bool sync)
2573{
2574	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
2575	struct nfs4_layoutcommit_data *data;
2576	struct nfs_inode *nfsi = NFS_I(inode);
2577	loff_t end_pos;
2578	int status;
2579
2580	if (!pnfs_layoutcommit_outstanding(inode))
2581		return 0;
2582
2583	dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
2584
2585	status = -EAGAIN;
2586	if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
2587		if (!sync)
2588			goto out;
2589		status = wait_on_bit_lock_action(&nfsi->flags,
2590				NFS_INO_LAYOUTCOMMITTING,
2591				nfs_wait_bit_killable,
2592				TASK_KILLABLE);
2593		if (status)
2594			goto out;
2595	}
2596
2597	status = -ENOMEM;
2598	/* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
2599	data = kzalloc(sizeof(*data), GFP_NOFS);
2600	if (!data)
2601		goto clear_layoutcommitting;
2602
2603	status = 0;
2604	spin_lock(&inode->i_lock);
2605	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
2606		goto out_unlock;
2607
2608	INIT_LIST_HEAD(&data->lseg_list);
2609	pnfs_list_write_lseg(inode, &data->lseg_list);
2610
2611	end_pos = nfsi->layout->plh_lwb;
2612
2613	nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
 
2614	spin_unlock(&inode->i_lock);
2615
2616	data->args.inode = inode;
2617	data->cred = get_rpccred(nfsi->layout->plh_lc_cred);
2618	nfs_fattr_init(&data->fattr);
2619	data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
2620	data->res.fattr = &data->fattr;
2621	if (end_pos != 0)
2622		data->args.lastbytewritten = end_pos - 1;
2623	else
2624		data->args.lastbytewritten = U64_MAX;
2625	data->res.server = NFS_SERVER(inode);
2626
2627	if (ld->prepare_layoutcommit) {
2628		status = ld->prepare_layoutcommit(&data->args);
2629		if (status) {
2630			put_rpccred(data->cred);
2631			spin_lock(&inode->i_lock);
2632			set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags);
2633			if (end_pos > nfsi->layout->plh_lwb)
2634				nfsi->layout->plh_lwb = end_pos;
2635			goto out_unlock;
2636		}
2637	}
2638
2639
2640	status = nfs4_proc_layoutcommit(data, sync);
2641out:
2642	if (status)
2643		mark_inode_dirty_sync(inode);
2644	dprintk("<-- %s status %d\n", __func__, status);
2645	return status;
2646out_unlock:
2647	spin_unlock(&inode->i_lock);
2648	kfree(data);
2649clear_layoutcommitting:
2650	pnfs_clear_layoutcommitting(inode);
2651	goto out;
2652}
2653EXPORT_SYMBOL_GPL(pnfs_layoutcommit_inode);
2654
2655int
2656pnfs_generic_sync(struct inode *inode, bool datasync)
2657{
2658	return pnfs_layoutcommit_inode(inode, true);
2659}
2660EXPORT_SYMBOL_GPL(pnfs_generic_sync);
2661
2662struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
2663{
2664	struct nfs4_threshold *thp;
2665
2666	thp = kzalloc(sizeof(*thp), GFP_NOFS);
2667	if (!thp) {
2668		dprintk("%s mdsthreshold allocation failed\n", __func__);
2669		return NULL;
2670	}
2671	return thp;
2672}
2673
2674#if IS_ENABLED(CONFIG_NFS_V4_2)
2675int
2676pnfs_report_layoutstat(struct inode *inode, gfp_t gfp_flags)
2677{
2678	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
2679	struct nfs_server *server = NFS_SERVER(inode);
2680	struct nfs_inode *nfsi = NFS_I(inode);
2681	struct nfs42_layoutstat_data *data;
2682	struct pnfs_layout_hdr *hdr;
2683	int status = 0;
2684
2685	if (!pnfs_enabled_sb(server) || !ld->prepare_layoutstats)
2686		goto out;
2687
2688	if (!nfs_server_capable(inode, NFS_CAP_LAYOUTSTATS))
2689		goto out;
2690
2691	if (test_and_set_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags))
2692		goto out;
2693
2694	spin_lock(&inode->i_lock);
2695	if (!NFS_I(inode)->layout) {
2696		spin_unlock(&inode->i_lock);
2697		goto out_clear_layoutstats;
2698	}
2699	hdr = NFS_I(inode)->layout;
2700	pnfs_get_layout_hdr(hdr);
2701	spin_unlock(&inode->i_lock);
2702
2703	data = kzalloc(sizeof(*data), gfp_flags);
2704	if (!data) {
2705		status = -ENOMEM;
2706		goto out_put;
2707	}
2708
2709	data->args.fh = NFS_FH(inode);
2710	data->args.inode = inode;
2711	status = ld->prepare_layoutstats(&data->args);
2712	if (status)
2713		goto out_free;
2714
2715	status = nfs42_proc_layoutstats_generic(NFS_SERVER(inode), data);
2716
2717out:
2718	dprintk("%s returns %d\n", __func__, status);
2719	return status;
2720
2721out_free:
2722	kfree(data);
2723out_put:
2724	pnfs_put_layout_hdr(hdr);
2725out_clear_layoutstats:
2726	smp_mb__before_atomic();
2727	clear_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags);
2728	smp_mb__after_atomic();
2729	goto out;
2730}
2731EXPORT_SYMBOL_GPL(pnfs_report_layoutstat);
2732#endif
2733
2734unsigned int layoutstats_timer;
2735module_param(layoutstats_timer, uint, 0644);
2736EXPORT_SYMBOL_GPL(layoutstats_timer);
v6.2
   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
  95const struct pnfs_layoutdriver_type *pnfs_find_layoutdriver(u32 id)
  96{
  97	return find_pnfs_driver(id);
  98}
  99
 100void pnfs_put_layoutdriver(const struct pnfs_layoutdriver_type *ld)
 101{
 102	if (ld)
 103		module_put(ld->owner);
 104}
 105
 106void
 107unset_pnfs_layoutdriver(struct nfs_server *nfss)
 108{
 109	if (nfss->pnfs_curr_ld) {
 110		if (nfss->pnfs_curr_ld->clear_layoutdriver)
 111			nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
 112		/* Decrement the MDS count. Purge the deviceid cache if zero */
 113		if (atomic_dec_and_test(&nfss->nfs_client->cl_mds_count))
 114			nfs4_deviceid_purge_client(nfss->nfs_client);
 115		module_put(nfss->pnfs_curr_ld->owner);
 116	}
 117	nfss->pnfs_curr_ld = NULL;
 118}
 119
 120/*
 121 * When the server sends a list of layout types, we choose one in the order
 122 * given in the list below.
 123 *
 124 * FIXME: should this list be configurable in some fashion? module param?
 125 * 	  mount option? something else?
 126 */
 127static const u32 ld_prefs[] = {
 128	LAYOUT_SCSI,
 129	LAYOUT_BLOCK_VOLUME,
 130	LAYOUT_OSD2_OBJECTS,
 131	LAYOUT_FLEX_FILES,
 132	LAYOUT_NFSV4_1_FILES,
 133	0
 134};
 135
 136static int
 137ld_cmp(const void *e1, const void *e2)
 138{
 139	u32 ld1 = *((u32 *)e1);
 140	u32 ld2 = *((u32 *)e2);
 141	int i;
 142
 143	for (i = 0; ld_prefs[i] != 0; i++) {
 144		if (ld1 == ld_prefs[i])
 145			return -1;
 146
 147		if (ld2 == ld_prefs[i])
 148			return 1;
 149	}
 150	return 0;
 151}
 152
 153/*
 154 * Try to set the server's pnfs module to the pnfs layout type specified by id.
 155 * Currently only one pNFS layout driver per filesystem is supported.
 156 *
 157 * @ids array of layout types supported by MDS.
 158 */
 159void
 160set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
 161		      struct nfs_fsinfo *fsinfo)
 162{
 163	struct pnfs_layoutdriver_type *ld_type = NULL;
 164	u32 id;
 165	int i;
 166
 167	if (fsinfo->nlayouttypes == 0)
 168		goto out_no_driver;
 169	if (!(server->nfs_client->cl_exchange_flags &
 170		 (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
 171		printk(KERN_ERR "NFS: %s: cl_exchange_flags 0x%x\n",
 172			__func__, server->nfs_client->cl_exchange_flags);
 173		goto out_no_driver;
 174	}
 175
 176	sort(fsinfo->layouttype, fsinfo->nlayouttypes,
 177		sizeof(*fsinfo->layouttype), ld_cmp, NULL);
 178
 179	for (i = 0; i < fsinfo->nlayouttypes; i++) {
 180		id = fsinfo->layouttype[i];
 181		ld_type = find_pnfs_driver(id);
 182		if (!ld_type) {
 183			request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX,
 184					id);
 185			ld_type = find_pnfs_driver(id);
 186		}
 187		if (ld_type)
 188			break;
 189	}
 190
 191	if (!ld_type) {
 192		dprintk("%s: No pNFS module found!\n", __func__);
 193		goto out_no_driver;
 194	}
 195
 196	server->pnfs_curr_ld = ld_type;
 197	if (ld_type->set_layoutdriver
 198	    && ld_type->set_layoutdriver(server, mntfh)) {
 199		printk(KERN_ERR "NFS: %s: Error initializing pNFS layout "
 200			"driver %u.\n", __func__, id);
 201		module_put(ld_type->owner);
 202		goto out_no_driver;
 203	}
 204	/* Bump the MDS count */
 205	atomic_inc(&server->nfs_client->cl_mds_count);
 206
 207	dprintk("%s: pNFS module for %u set\n", __func__, id);
 208	return;
 209
 210out_no_driver:
 211	dprintk("%s: Using NFSv4 I/O\n", __func__);
 212	server->pnfs_curr_ld = NULL;
 213}
 214
 215int
 216pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 217{
 218	int status = -EINVAL;
 219	struct pnfs_layoutdriver_type *tmp;
 220
 221	if (ld_type->id == 0) {
 222		printk(KERN_ERR "NFS: %s id 0 is reserved\n", __func__);
 223		return status;
 224	}
 225	if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
 226		printk(KERN_ERR "NFS: %s Layout driver must provide "
 227		       "alloc_lseg and free_lseg.\n", __func__);
 228		return status;
 229	}
 230
 231	spin_lock(&pnfs_spinlock);
 232	tmp = find_pnfs_driver_locked(ld_type->id);
 233	if (!tmp) {
 234		list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
 235		status = 0;
 236		dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
 237			ld_type->name);
 238	} else {
 239		printk(KERN_ERR "NFS: %s Module with id %d already loaded!\n",
 240			__func__, ld_type->id);
 241	}
 242	spin_unlock(&pnfs_spinlock);
 243
 244	return status;
 245}
 246EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);
 247
 248void
 249pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 250{
 251	dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
 252	spin_lock(&pnfs_spinlock);
 253	list_del(&ld_type->pnfs_tblid);
 254	spin_unlock(&pnfs_spinlock);
 255}
 256EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
 257
 258/*
 259 * pNFS client layout cache
 260 */
 261
 262/* Need to hold i_lock if caller does not already hold reference */
 263void
 264pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo)
 265{
 266	refcount_inc(&lo->plh_refcount);
 267}
 268
 269static struct pnfs_layout_hdr *
 270pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags)
 271{
 272	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
 273	return ld->alloc_layout_hdr(ino, gfp_flags);
 274}
 275
 276static void
 277pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
 278{
 279	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
 280	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
 281
 282	if (test_and_clear_bit(NFS_LAYOUT_HASHED, &lo->plh_flags)) {
 283		struct nfs_client *clp = server->nfs_client;
 284
 285		spin_lock(&clp->cl_lock);
 286		list_del_rcu(&lo->plh_layouts);
 287		spin_unlock(&clp->cl_lock);
 288	}
 289	put_cred(lo->plh_lc_cred);
 290	return ld->free_layout_hdr(lo);
 291}
 292
 293static void
 294pnfs_detach_layout_hdr(struct pnfs_layout_hdr *lo)
 295{
 296	struct nfs_inode *nfsi = NFS_I(lo->plh_inode);
 297	dprintk("%s: freeing layout cache %p\n", __func__, lo);
 298	nfsi->layout = NULL;
 299	/* Reset MDS Threshold I/O counters */
 300	nfsi->write_io = 0;
 301	nfsi->read_io = 0;
 302}
 303
 304void
 305pnfs_put_layout_hdr(struct pnfs_layout_hdr *lo)
 306{
 307	struct inode *inode;
 308	unsigned long i_state;
 309
 310	if (!lo)
 311		return;
 312	inode = lo->plh_inode;
 313	pnfs_layoutreturn_before_put_layout_hdr(lo);
 314
 315	if (refcount_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
 316		if (!list_empty(&lo->plh_segs))
 317			WARN_ONCE(1, "NFS: BUG unfreed layout segments.\n");
 318		pnfs_detach_layout_hdr(lo);
 319		i_state = inode->i_state;
 320		spin_unlock(&inode->i_lock);
 321		pnfs_free_layout_hdr(lo);
 322		/* Notify pnfs_destroy_layout_final() that we're done */
 323		if (i_state & (I_FREEING | I_CLEAR))
 324			wake_up_var(lo);
 325	}
 326}
 327
 328static struct inode *
 329pnfs_grab_inode_layout_hdr(struct pnfs_layout_hdr *lo)
 330{
 331	struct inode *inode = igrab(lo->plh_inode);
 332	if (inode)
 333		return inode;
 334	set_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags);
 335	return NULL;
 336}
 337
 338/*
 339 * Compare 2 layout stateid sequence ids, to see which is newer,
 340 * taking into account wraparound issues.
 341 */
 342static bool pnfs_seqid_is_newer(u32 s1, u32 s2)
 343{
 344	return (s32)(s1 - s2) > 0;
 345}
 346
 347static void pnfs_barrier_update(struct pnfs_layout_hdr *lo, u32 newseq)
 348{
 349	if (pnfs_seqid_is_newer(newseq, lo->plh_barrier) || !lo->plh_barrier)
 350		lo->plh_barrier = newseq;
 351}
 352
 353static void
 354pnfs_set_plh_return_info(struct pnfs_layout_hdr *lo, enum pnfs_iomode iomode,
 355			 u32 seq)
 356{
 357	if (lo->plh_return_iomode != 0 && lo->plh_return_iomode != iomode)
 358		iomode = IOMODE_ANY;
 359	lo->plh_return_iomode = iomode;
 360	set_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 361	/*
 362	 * We must set lo->plh_return_seq to avoid livelocks with
 363	 * pnfs_layout_need_return()
 364	 */
 365	if (seq == 0)
 366		seq = be32_to_cpu(lo->plh_stateid.seqid);
 367	if (!lo->plh_return_seq || pnfs_seqid_is_newer(seq, lo->plh_return_seq))
 368		lo->plh_return_seq = seq;
 369	pnfs_barrier_update(lo, seq);
 370}
 371
 372static void
 373pnfs_clear_layoutreturn_info(struct pnfs_layout_hdr *lo)
 374{
 375	struct pnfs_layout_segment *lseg;
 376	lo->plh_return_iomode = 0;
 377	lo->plh_return_seq = 0;
 378	clear_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 379	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
 380		if (!test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
 381			continue;
 382		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
 383	}
 384}
 385
 386static void pnfs_clear_layoutreturn_waitbit(struct pnfs_layout_hdr *lo)
 387{
 388	clear_bit_unlock(NFS_LAYOUT_RETURN, &lo->plh_flags);
 389	clear_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags);
 390	smp_mb__after_atomic();
 391	wake_up_bit(&lo->plh_flags, NFS_LAYOUT_RETURN);
 392	rpc_wake_up(&NFS_SERVER(lo->plh_inode)->roc_rpcwaitq);
 393}
 394
 395static void
 396pnfs_clear_lseg_state(struct pnfs_layout_segment *lseg,
 397		struct list_head *free_me)
 398{
 399	clear_bit(NFS_LSEG_ROC, &lseg->pls_flags);
 400	clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
 401	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags))
 402		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 403	if (test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
 404		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 405}
 406
 407/*
 408 * Update the seqid of a layout stateid after receiving
 409 * NFS4ERR_OLD_STATEID
 410 */
 411bool nfs4_layout_refresh_old_stateid(nfs4_stateid *dst,
 412		struct pnfs_layout_range *dst_range,
 413		struct inode *inode)
 414{
 415	struct pnfs_layout_hdr *lo;
 416	struct pnfs_layout_range range = {
 417		.iomode = IOMODE_ANY,
 418		.offset = 0,
 419		.length = NFS4_MAX_UINT64,
 420	};
 421	bool ret = false;
 422	LIST_HEAD(head);
 423	int err;
 424
 425	spin_lock(&inode->i_lock);
 426	lo = NFS_I(inode)->layout;
 427	if (lo &&  pnfs_layout_is_valid(lo) &&
 428	    nfs4_stateid_match_other(dst, &lo->plh_stateid)) {
 429		/* Is our call using the most recent seqid? If so, bump it */
 430		if (!nfs4_stateid_is_newer(&lo->plh_stateid, dst)) {
 431			nfs4_stateid_seqid_inc(dst);
 432			ret = true;
 433			goto out;
 434		}
 435		/* Try to update the seqid to the most recent */
 436		err = pnfs_mark_matching_lsegs_return(lo, &head, &range, 0);
 437		if (err != -EBUSY) {
 438			dst->seqid = lo->plh_stateid.seqid;
 439			*dst_range = range;
 440			ret = true;
 441		}
 442	}
 443out:
 444	spin_unlock(&inode->i_lock);
 445	pnfs_free_lseg_list(&head);
 446	return ret;
 447}
 448
 449/*
 450 * Mark a pnfs_layout_hdr and all associated layout segments as invalid
 451 *
 452 * In order to continue using the pnfs_layout_hdr, a full recovery
 453 * is required.
 454 * Note that caller must hold inode->i_lock.
 455 */
 456int
 457pnfs_mark_layout_stateid_invalid(struct pnfs_layout_hdr *lo,
 458		struct list_head *lseg_list)
 459{
 460	struct pnfs_layout_range range = {
 461		.iomode = IOMODE_ANY,
 462		.offset = 0,
 463		.length = NFS4_MAX_UINT64,
 464	};
 465	struct pnfs_layout_segment *lseg, *next;
 466
 467	set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 468	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 469		pnfs_clear_lseg_state(lseg, lseg_list);
 470	pnfs_clear_layoutreturn_info(lo);
 471	pnfs_free_returned_lsegs(lo, lseg_list, &range, 0);
 472	set_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags);
 473	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags) &&
 474	    !test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
 475		pnfs_clear_layoutreturn_waitbit(lo);
 476	return !list_empty(&lo->plh_segs);
 477}
 478
 479static int
 480pnfs_iomode_to_fail_bit(u32 iomode)
 481{
 482	return iomode == IOMODE_RW ?
 483		NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 484}
 485
 486static void
 487pnfs_layout_set_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 488{
 489	lo->plh_retry_timestamp = jiffies;
 490	if (!test_and_set_bit(fail_bit, &lo->plh_flags))
 491		refcount_inc(&lo->plh_refcount);
 492}
 493
 494static void
 495pnfs_layout_clear_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 496{
 497	if (test_and_clear_bit(fail_bit, &lo->plh_flags))
 498		refcount_dec(&lo->plh_refcount);
 499}
 500
 501static void
 502pnfs_layout_io_set_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 503{
 504	struct inode *inode = lo->plh_inode;
 505	struct pnfs_layout_range range = {
 506		.iomode = iomode,
 507		.offset = 0,
 508		.length = NFS4_MAX_UINT64,
 509	};
 510	LIST_HEAD(head);
 511
 512	spin_lock(&inode->i_lock);
 513	pnfs_layout_set_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
 514	pnfs_mark_matching_lsegs_invalid(lo, &head, &range, 0);
 515	spin_unlock(&inode->i_lock);
 516	pnfs_free_lseg_list(&head);
 517	dprintk("%s Setting layout IOMODE_%s fail bit\n", __func__,
 518			iomode == IOMODE_RW ?  "RW" : "READ");
 519}
 520
 521static bool
 522pnfs_layout_io_test_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 523{
 524	unsigned long start, end;
 525	int fail_bit = pnfs_iomode_to_fail_bit(iomode);
 526
 527	if (test_bit(fail_bit, &lo->plh_flags) == 0)
 528		return false;
 529	end = jiffies;
 530	start = end - PNFS_LAYOUTGET_RETRY_TIMEOUT;
 531	if (!time_in_range(lo->plh_retry_timestamp, start, end)) {
 532		/* It is time to retry the failed layoutgets */
 533		pnfs_layout_clear_fail_bit(lo, fail_bit);
 534		return false;
 535	}
 536	return true;
 537}
 538
 539static void
 540pnfs_init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg,
 541		const struct pnfs_layout_range *range,
 542		const nfs4_stateid *stateid)
 543{
 544	INIT_LIST_HEAD(&lseg->pls_list);
 545	INIT_LIST_HEAD(&lseg->pls_lc_list);
 546	INIT_LIST_HEAD(&lseg->pls_commits);
 547	refcount_set(&lseg->pls_refcount, 1);
 548	set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
 549	lseg->pls_layout = lo;
 550	lseg->pls_range = *range;
 551	lseg->pls_seq = be32_to_cpu(stateid->seqid);
 552}
 553
 554static void pnfs_free_lseg(struct pnfs_layout_segment *lseg)
 555{
 556	if (lseg != NULL) {
 557		struct inode *inode = lseg->pls_layout->plh_inode;
 558		NFS_SERVER(inode)->pnfs_curr_ld->free_lseg(lseg);
 559	}
 560}
 561
 562static void
 563pnfs_layout_remove_lseg(struct pnfs_layout_hdr *lo,
 564		struct pnfs_layout_segment *lseg)
 565{
 566	WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 567	list_del_init(&lseg->pls_list);
 568	/* Matched by pnfs_get_layout_hdr in pnfs_layout_insert_lseg */
 569	refcount_dec(&lo->plh_refcount);
 570	if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
 571		return;
 572	if (list_empty(&lo->plh_segs) &&
 573	    !test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) &&
 574	    !test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
 575		if (atomic_read(&lo->plh_outstanding) == 0)
 576			set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 577		clear_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 578	}
 579}
 580
 581static bool
 582pnfs_cache_lseg_for_layoutreturn(struct pnfs_layout_hdr *lo,
 583		struct pnfs_layout_segment *lseg)
 584{
 585	if (test_and_clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags) &&
 586	    pnfs_layout_is_valid(lo)) {
 587		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
 588		list_move_tail(&lseg->pls_list, &lo->plh_return_segs);
 589		return true;
 590	}
 591	return false;
 592}
 593
 594void
 595pnfs_put_lseg(struct pnfs_layout_segment *lseg)
 596{
 597	struct pnfs_layout_hdr *lo;
 598	struct inode *inode;
 599
 600	if (!lseg)
 601		return;
 602
 603	dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
 604		refcount_read(&lseg->pls_refcount),
 605		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 606
 607	lo = lseg->pls_layout;
 608	inode = lo->plh_inode;
 609
 610	if (refcount_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
 
 
 
 
 611		pnfs_get_layout_hdr(lo);
 612		pnfs_layout_remove_lseg(lo, lseg);
 613		if (pnfs_cache_lseg_for_layoutreturn(lo, lseg))
 614			lseg = NULL;
 615		spin_unlock(&inode->i_lock);
 616		pnfs_free_lseg(lseg);
 617		pnfs_put_layout_hdr(lo);
 618	}
 619}
 620EXPORT_SYMBOL_GPL(pnfs_put_lseg);
 621
 622/*
 623 * is l2 fully contained in l1?
 624 *   start1                             end1
 625 *   [----------------------------------)
 626 *           start2           end2
 627 *           [----------------)
 628 */
 629static bool
 630pnfs_lseg_range_contained(const struct pnfs_layout_range *l1,
 631		 const struct pnfs_layout_range *l2)
 632{
 633	u64 start1 = l1->offset;
 634	u64 end1 = pnfs_end_offset(start1, l1->length);
 635	u64 start2 = l2->offset;
 636	u64 end2 = pnfs_end_offset(start2, l2->length);
 637
 638	return (start1 <= start2) && (end1 >= end2);
 639}
 640
 641static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
 642		struct list_head *tmp_list)
 643{
 644	if (!refcount_dec_and_test(&lseg->pls_refcount))
 645		return false;
 646	pnfs_layout_remove_lseg(lseg->pls_layout, lseg);
 647	list_add(&lseg->pls_list, tmp_list);
 648	return true;
 649}
 650
 651/* Returns 1 if lseg is removed from list, 0 otherwise */
 652static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
 653			     struct list_head *tmp_list)
 654{
 655	int rv = 0;
 656
 657	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 658		/* Remove the reference keeping the lseg in the
 659		 * list.  It will now be removed when all
 660		 * outstanding io is finished.
 661		 */
 662		dprintk("%s: lseg %p ref %d\n", __func__, lseg,
 663			refcount_read(&lseg->pls_refcount));
 664		if (pnfs_lseg_dec_and_remove_zero(lseg, tmp_list))
 665			rv = 1;
 666	}
 667	return rv;
 668}
 669
 
 
 
 
 
 
 
 
 
 670static bool
 671pnfs_should_free_range(const struct pnfs_layout_range *lseg_range,
 672		 const struct pnfs_layout_range *recall_range)
 673{
 674	return (recall_range->iomode == IOMODE_ANY ||
 675		lseg_range->iomode == recall_range->iomode) &&
 676	       pnfs_lseg_range_intersecting(lseg_range, recall_range);
 677}
 678
 679static bool
 680pnfs_match_lseg_recall(const struct pnfs_layout_segment *lseg,
 681		const struct pnfs_layout_range *recall_range,
 682		u32 seq)
 683{
 684	if (seq != 0 && pnfs_seqid_is_newer(lseg->pls_seq, seq))
 685		return false;
 686	if (recall_range == NULL)
 687		return true;
 688	return pnfs_should_free_range(&lseg->pls_range, recall_range);
 689}
 690
 691/**
 692 * pnfs_mark_matching_lsegs_invalid - tear down lsegs or mark them for later
 693 * @lo: layout header containing the lsegs
 694 * @tmp_list: list head where doomed lsegs should go
 695 * @recall_range: optional recall range argument to match (may be NULL)
 696 * @seq: only invalidate lsegs obtained prior to this sequence (may be 0)
 697 *
 698 * Walk the list of lsegs in the layout header, and tear down any that should
 699 * be destroyed. If "recall_range" is specified then the segment must match
 700 * that range. If "seq" is non-zero, then only match segments that were handed
 701 * out at or before that sequence.
 702 *
 703 * Returns number of matching invalid lsegs remaining in list after scanning
 704 * it and purging them.
 705 */
 706int
 707pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 708			    struct list_head *tmp_list,
 709			    const struct pnfs_layout_range *recall_range,
 710			    u32 seq)
 711{
 712	struct pnfs_layout_segment *lseg, *next;
 713	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
 714	int remaining = 0;
 715
 716	dprintk("%s:Begin lo %p\n", __func__, lo);
 717
 718	if (list_empty(&lo->plh_segs))
 719		return 0;
 720	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 721		if (pnfs_match_lseg_recall(lseg, recall_range, seq)) {
 722			dprintk("%s: freeing lseg %p iomode %d seq %u "
 723				"offset %llu length %llu\n", __func__,
 724				lseg, lseg->pls_range.iomode, lseg->pls_seq,
 725				lseg->pls_range.offset, lseg->pls_range.length);
 726			if (mark_lseg_invalid(lseg, tmp_list))
 727				continue;
 728			remaining++;
 729			pnfs_lseg_cancel_io(server, lseg);
 730		}
 731	dprintk("%s:Return %i\n", __func__, remaining);
 732	return remaining;
 733}
 734
 735static void
 736pnfs_free_returned_lsegs(struct pnfs_layout_hdr *lo,
 737		struct list_head *free_me,
 738		const struct pnfs_layout_range *range,
 739		u32 seq)
 740{
 741	struct pnfs_layout_segment *lseg, *next;
 742
 743	list_for_each_entry_safe(lseg, next, &lo->plh_return_segs, pls_list) {
 744		if (pnfs_match_lseg_recall(lseg, range, seq))
 745			list_move_tail(&lseg->pls_list, free_me);
 746	}
 747}
 748
 749/* note free_me must contain lsegs from a single layout_hdr */
 750void
 751pnfs_free_lseg_list(struct list_head *free_me)
 752{
 753	struct pnfs_layout_segment *lseg, *tmp;
 754
 755	if (list_empty(free_me))
 756		return;
 757
 758	list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
 759		list_del(&lseg->pls_list);
 760		pnfs_free_lseg(lseg);
 761	}
 762}
 763
 764static struct pnfs_layout_hdr *__pnfs_destroy_layout(struct nfs_inode *nfsi)
 
 765{
 766	struct pnfs_layout_hdr *lo;
 767	LIST_HEAD(tmp_list);
 768
 769	spin_lock(&nfsi->vfs_inode.i_lock);
 770	lo = nfsi->layout;
 771	if (lo) {
 772		pnfs_get_layout_hdr(lo);
 773		pnfs_mark_layout_stateid_invalid(lo, &tmp_list);
 774		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RO_FAILED);
 775		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RW_FAILED);
 776		spin_unlock(&nfsi->vfs_inode.i_lock);
 777		pnfs_free_lseg_list(&tmp_list);
 778		nfs_commit_inode(&nfsi->vfs_inode, 0);
 779		pnfs_put_layout_hdr(lo);
 780	} else
 781		spin_unlock(&nfsi->vfs_inode.i_lock);
 782	return lo;
 783}
 784
 785void pnfs_destroy_layout(struct nfs_inode *nfsi)
 786{
 787	__pnfs_destroy_layout(nfsi);
 788}
 789EXPORT_SYMBOL_GPL(pnfs_destroy_layout);
 790
 791static bool pnfs_layout_removed(struct nfs_inode *nfsi,
 792				struct pnfs_layout_hdr *lo)
 793{
 794	bool ret;
 795
 796	spin_lock(&nfsi->vfs_inode.i_lock);
 797	ret = nfsi->layout != lo;
 798	spin_unlock(&nfsi->vfs_inode.i_lock);
 799	return ret;
 800}
 801
 802void pnfs_destroy_layout_final(struct nfs_inode *nfsi)
 803{
 804	struct pnfs_layout_hdr *lo = __pnfs_destroy_layout(nfsi);
 805
 806	if (lo)
 807		wait_var_event(lo, pnfs_layout_removed(nfsi, lo));
 808}
 809
 810static bool
 811pnfs_layout_add_bulk_destroy_list(struct inode *inode,
 812		struct list_head *layout_list)
 813{
 814	struct pnfs_layout_hdr *lo;
 815	bool ret = false;
 816
 817	spin_lock(&inode->i_lock);
 818	lo = NFS_I(inode)->layout;
 819	if (lo != NULL && list_empty(&lo->plh_bulk_destroy)) {
 820		pnfs_get_layout_hdr(lo);
 821		list_add(&lo->plh_bulk_destroy, layout_list);
 822		ret = true;
 823	}
 824	spin_unlock(&inode->i_lock);
 825	return ret;
 826}
 827
 828/* Caller must hold rcu_read_lock and clp->cl_lock */
 829static int
 830pnfs_layout_bulk_destroy_byserver_locked(struct nfs_client *clp,
 831		struct nfs_server *server,
 832		struct list_head *layout_list)
 833	__must_hold(&clp->cl_lock)
 834	__must_hold(RCU)
 835{
 836	struct pnfs_layout_hdr *lo, *next;
 837	struct inode *inode;
 838
 839	list_for_each_entry_safe(lo, next, &server->layouts, plh_layouts) {
 840		if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags) ||
 841		    test_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags) ||
 842		    !list_empty(&lo->plh_bulk_destroy))
 843			continue;
 844		/* If the sb is being destroyed, just bail */
 845		if (!nfs_sb_active(server->super))
 846			break;
 847		inode = pnfs_grab_inode_layout_hdr(lo);
 848		if (inode != NULL) {
 849			if (test_and_clear_bit(NFS_LAYOUT_HASHED, &lo->plh_flags))
 850				list_del_rcu(&lo->plh_layouts);
 851			if (pnfs_layout_add_bulk_destroy_list(inode,
 852						layout_list))
 853				continue;
 854			rcu_read_unlock();
 855			spin_unlock(&clp->cl_lock);
 856			iput(inode);
 857		} else {
 858			rcu_read_unlock();
 859			spin_unlock(&clp->cl_lock);
 860		}
 861		nfs_sb_deactive(server->super);
 862		spin_lock(&clp->cl_lock);
 863		rcu_read_lock();
 864		return -EAGAIN;
 865	}
 866	return 0;
 867}
 868
 869static int
 870pnfs_layout_free_bulk_destroy_list(struct list_head *layout_list,
 871		bool is_bulk_recall)
 872{
 873	struct pnfs_layout_hdr *lo;
 874	struct inode *inode;
 875	LIST_HEAD(lseg_list);
 876	int ret = 0;
 877
 878	while (!list_empty(layout_list)) {
 879		lo = list_entry(layout_list->next, struct pnfs_layout_hdr,
 880				plh_bulk_destroy);
 881		dprintk("%s freeing layout for inode %lu\n", __func__,
 882			lo->plh_inode->i_ino);
 883		inode = lo->plh_inode;
 884
 885		pnfs_layoutcommit_inode(inode, false);
 886
 887		spin_lock(&inode->i_lock);
 888		list_del_init(&lo->plh_bulk_destroy);
 889		if (pnfs_mark_layout_stateid_invalid(lo, &lseg_list)) {
 890			if (is_bulk_recall)
 891				set_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 892			ret = -EAGAIN;
 893		}
 894		spin_unlock(&inode->i_lock);
 895		pnfs_free_lseg_list(&lseg_list);
 896		/* Free all lsegs that are attached to commit buckets */
 897		nfs_commit_inode(inode, 0);
 898		pnfs_put_layout_hdr(lo);
 899		nfs_iput_and_deactive(inode);
 900	}
 901	return ret;
 902}
 903
 904int
 905pnfs_destroy_layouts_byfsid(struct nfs_client *clp,
 906		struct nfs_fsid *fsid,
 907		bool is_recall)
 908{
 909	struct nfs_server *server;
 910	LIST_HEAD(layout_list);
 911
 912	spin_lock(&clp->cl_lock);
 913	rcu_read_lock();
 914restart:
 915	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 916		if (memcmp(&server->fsid, fsid, sizeof(*fsid)) != 0)
 917			continue;
 918		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 919				server,
 920				&layout_list) != 0)
 921			goto restart;
 922	}
 923	rcu_read_unlock();
 924	spin_unlock(&clp->cl_lock);
 925
 926	if (list_empty(&layout_list))
 927		return 0;
 928	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 929}
 930
 931int
 932pnfs_destroy_layouts_byclid(struct nfs_client *clp,
 933		bool is_recall)
 934{
 935	struct nfs_server *server;
 936	LIST_HEAD(layout_list);
 937
 938	spin_lock(&clp->cl_lock);
 939	rcu_read_lock();
 940restart:
 941	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 942		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 943					server,
 944					&layout_list) != 0)
 945			goto restart;
 946	}
 947	rcu_read_unlock();
 948	spin_unlock(&clp->cl_lock);
 949
 950	if (list_empty(&layout_list))
 951		return 0;
 952	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 953}
 954
 955/*
 956 * Called by the state manager to remove all layouts established under an
 957 * expired lease.
 958 */
 959void
 960pnfs_destroy_all_layouts(struct nfs_client *clp)
 961{
 962	nfs4_deviceid_mark_client_invalid(clp);
 963	nfs4_deviceid_purge_client(clp);
 964
 965	pnfs_destroy_layouts_byclid(clp, false);
 966}
 967
 968static void
 969pnfs_set_layout_cred(struct pnfs_layout_hdr *lo, const struct cred *cred)
 970{
 971	const struct cred *old;
 972
 973	if (cred && cred_fscmp(lo->plh_lc_cred, cred) != 0) {
 974		old = xchg(&lo->plh_lc_cred, get_cred(cred));
 975		put_cred(old);
 976	}
 977}
 978
 979/* update lo->plh_stateid with new if is more recent */
 980void
 981pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
 982			const struct cred *cred, bool update_barrier)
 983{
 984	u32 oldseq = be32_to_cpu(lo->plh_stateid.seqid);
 985	u32 newseq = be32_to_cpu(new->seqid);
 
 
 986
 987	if (!pnfs_layout_is_valid(lo)) {
 988		pnfs_set_layout_cred(lo, cred);
 989		nfs4_stateid_copy(&lo->plh_stateid, new);
 990		lo->plh_barrier = newseq;
 991		pnfs_clear_layoutreturn_info(lo);
 992		clear_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 993		return;
 994	}
 995
 996	if (pnfs_seqid_is_newer(newseq, oldseq))
 997		nfs4_stateid_copy(&lo->plh_stateid, new);
 998
 999	if (update_barrier) {
1000		pnfs_barrier_update(lo, newseq);
 
 
 
 
 
 
1001		return;
1002	}
1003	/*
1004	 * Because of wraparound, we want to keep the barrier
1005	 * "close" to the current seqids. We really only want to
1006	 * get here from a layoutget call.
1007	 */
1008	if (atomic_read(&lo->plh_outstanding) == 1)
1009		 pnfs_barrier_update(lo, be32_to_cpu(lo->plh_stateid.seqid));
1010}
1011
1012static bool
1013pnfs_layout_stateid_blocked(const struct pnfs_layout_hdr *lo,
1014		const nfs4_stateid *stateid)
1015{
1016	u32 seqid = be32_to_cpu(stateid->seqid);
1017
1018	return lo->plh_barrier && pnfs_seqid_is_newer(lo->plh_barrier, seqid);
1019}
1020
1021/* lget is set to 1 if called from inside send_layoutget call chain */
1022static bool
1023pnfs_layoutgets_blocked(const struct pnfs_layout_hdr *lo)
1024{
1025	return lo->plh_block_lgets ||
1026		test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
1027}
1028
1029static struct nfs_server *
1030pnfs_find_server(struct inode *inode, struct nfs_open_context *ctx)
1031{
1032	struct nfs_server *server;
1033
1034	if (inode) {
1035		server = NFS_SERVER(inode);
1036	} else {
1037		struct dentry *parent_dir = dget_parent(ctx->dentry);
1038		server = NFS_SERVER(parent_dir->d_inode);
1039		dput(parent_dir);
1040	}
1041	return server;
1042}
1043
1044static void nfs4_free_pages(struct page **pages, size_t size)
1045{
1046	int i;
1047
1048	if (!pages)
1049		return;
1050
1051	for (i = 0; i < size; i++) {
1052		if (!pages[i])
1053			break;
1054		__free_page(pages[i]);
1055	}
1056	kfree(pages);
1057}
1058
1059static struct page **nfs4_alloc_pages(size_t size, gfp_t gfp_flags)
1060{
1061	struct page **pages;
1062	int i;
1063
1064	pages = kmalloc_array(size, sizeof(struct page *), gfp_flags);
1065	if (!pages) {
1066		dprintk("%s: can't alloc array of %zu pages\n", __func__, size);
1067		return NULL;
1068	}
1069
1070	for (i = 0; i < size; i++) {
1071		pages[i] = alloc_page(gfp_flags);
1072		if (!pages[i]) {
1073			dprintk("%s: failed to allocate page\n", __func__);
1074			nfs4_free_pages(pages, i);
1075			return NULL;
1076		}
1077	}
1078
1079	return pages;
1080}
1081
1082static struct nfs4_layoutget *
1083pnfs_alloc_init_layoutget_args(struct inode *ino,
1084	   struct nfs_open_context *ctx,
1085	   const nfs4_stateid *stateid,
1086	   const struct pnfs_layout_range *range,
1087	   gfp_t gfp_flags)
1088{
1089	struct nfs_server *server = pnfs_find_server(ino, ctx);
1090	size_t max_reply_sz = server->pnfs_curr_ld->max_layoutget_response;
1091	size_t max_pages = max_response_pages(server);
1092	struct nfs4_layoutget *lgp;
 
1093
1094	dprintk("--> %s\n", __func__);
1095
 
 
 
 
 
1096	lgp = kzalloc(sizeof(*lgp), gfp_flags);
1097	if (lgp == NULL)
1098		return NULL;
1099
1100	if (max_reply_sz) {
1101		size_t npages = (max_reply_sz + PAGE_SIZE - 1) >> PAGE_SHIFT;
1102		if (npages < max_pages)
1103			max_pages = npages;
1104	}
1105
1106	lgp->args.layout.pages = nfs4_alloc_pages(max_pages, gfp_flags);
1107	if (!lgp->args.layout.pages) {
1108		kfree(lgp);
1109		return NULL;
1110	}
1111	lgp->args.layout.pglen = max_pages * PAGE_SIZE;
1112	lgp->res.layoutp = &lgp->args.layout;
1113
1114	/* Don't confuse uninitialised result and success */
1115	lgp->res.status = -NFS4ERR_DELAY;
1116
1117	lgp->args.minlength = PAGE_SIZE;
1118	if (lgp->args.minlength > range->length)
1119		lgp->args.minlength = range->length;
1120	if (ino) {
1121		loff_t i_size = i_size_read(ino);
1122
1123		if (range->iomode == IOMODE_READ) {
1124			if (range->offset >= i_size)
1125				lgp->args.minlength = 0;
1126			else if (i_size - range->offset < lgp->args.minlength)
1127				lgp->args.minlength = i_size - range->offset;
1128		}
1129	}
1130	lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
1131	pnfs_copy_range(&lgp->args.range, range);
1132	lgp->args.type = server->pnfs_curr_ld->id;
1133	lgp->args.inode = ino;
1134	lgp->args.ctx = get_nfs_open_context(ctx);
1135	nfs4_stateid_copy(&lgp->args.stateid, stateid);
1136	lgp->gfp_flags = gfp_flags;
1137	lgp->cred = ctx->cred;
1138	return lgp;
1139}
1140
1141void pnfs_layoutget_free(struct nfs4_layoutget *lgp)
1142{
1143	size_t max_pages = lgp->args.layout.pglen / PAGE_SIZE;
1144
1145	nfs4_free_pages(lgp->args.layout.pages, max_pages);
1146	pnfs_put_layout_hdr(lgp->lo);
1147	put_nfs_open_context(lgp->args.ctx);
1148	kfree(lgp);
1149}
1150
1151static void pnfs_clear_layoutcommit(struct inode *inode,
1152		struct list_head *head)
1153{
1154	struct nfs_inode *nfsi = NFS_I(inode);
1155	struct pnfs_layout_segment *lseg, *tmp;
1156
1157	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
1158		return;
1159	list_for_each_entry_safe(lseg, tmp, &nfsi->layout->plh_segs, pls_list) {
1160		if (!test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
1161			continue;
1162		pnfs_lseg_dec_and_remove_zero(lseg, head);
1163	}
1164}
1165
1166void pnfs_layoutreturn_free_lsegs(struct pnfs_layout_hdr *lo,
1167		const nfs4_stateid *arg_stateid,
1168		const struct pnfs_layout_range *range,
1169		const nfs4_stateid *stateid)
1170{
1171	struct inode *inode = lo->plh_inode;
1172	LIST_HEAD(freeme);
1173
1174	spin_lock(&inode->i_lock);
1175	if (!pnfs_layout_is_valid(lo) ||
1176	    !nfs4_stateid_match_other(&lo->plh_stateid, arg_stateid))
1177		goto out_unlock;
1178	if (stateid) {
1179		u32 seq = be32_to_cpu(arg_stateid->seqid);
1180
1181		pnfs_mark_matching_lsegs_invalid(lo, &freeme, range, seq);
1182		pnfs_free_returned_lsegs(lo, &freeme, range, seq);
1183		pnfs_set_layout_stateid(lo, stateid, NULL, true);
1184	} else
1185		pnfs_mark_layout_stateid_invalid(lo, &freeme);
1186out_unlock:
1187	pnfs_clear_layoutreturn_waitbit(lo);
1188	spin_unlock(&inode->i_lock);
1189	pnfs_free_lseg_list(&freeme);
1190
1191}
1192
1193static bool
1194pnfs_prepare_layoutreturn(struct pnfs_layout_hdr *lo,
1195		nfs4_stateid *stateid,
1196		const struct cred **cred,
1197		enum pnfs_iomode *iomode)
1198{
1199	/* Serialise LAYOUTGET/LAYOUTRETURN */
1200	if (atomic_read(&lo->plh_outstanding) != 0)
1201		return false;
1202	if (test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
1203		return false;
1204	set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
1205	pnfs_get_layout_hdr(lo);
1206	nfs4_stateid_copy(stateid, &lo->plh_stateid);
1207	*cred = get_cred(lo->plh_lc_cred);
1208	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags)) {
1209		if (lo->plh_return_seq != 0)
1210			stateid->seqid = cpu_to_be32(lo->plh_return_seq);
 
 
 
1211		if (iomode != NULL)
1212			*iomode = lo->plh_return_iomode;
1213		pnfs_clear_layoutreturn_info(lo);
1214	} else if (iomode != NULL)
 
 
 
 
1215		*iomode = IOMODE_ANY;
1216	pnfs_barrier_update(lo, be32_to_cpu(stateid->seqid));
1217	return true;
1218}
1219
1220static void
1221pnfs_init_layoutreturn_args(struct nfs4_layoutreturn_args *args,
1222		struct pnfs_layout_hdr *lo,
1223		const nfs4_stateid *stateid,
1224		enum pnfs_iomode iomode)
1225{
1226	struct inode *inode = lo->plh_inode;
1227
1228	args->layout_type = NFS_SERVER(inode)->pnfs_curr_ld->id;
1229	args->inode = inode;
1230	args->range.iomode = iomode;
1231	args->range.offset = 0;
1232	args->range.length = NFS4_MAX_UINT64;
1233	args->layout = lo;
1234	nfs4_stateid_copy(&args->stateid, stateid);
1235}
1236
1237static int
1238pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo,
1239		       const nfs4_stateid *stateid,
1240		       const struct cred **pcred,
1241		       enum pnfs_iomode iomode,
1242		       bool sync)
1243{
1244	struct inode *ino = lo->plh_inode;
1245	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1246	struct nfs4_layoutreturn *lrp;
1247	const struct cred *cred = *pcred;
1248	int status = 0;
1249
1250	*pcred = NULL;
1251	lrp = kzalloc(sizeof(*lrp), nfs_io_gfp_mask());
1252	if (unlikely(lrp == NULL)) {
1253		status = -ENOMEM;
1254		spin_lock(&ino->i_lock);
1255		pnfs_clear_layoutreturn_waitbit(lo);
1256		spin_unlock(&ino->i_lock);
1257		put_cred(cred);
1258		pnfs_put_layout_hdr(lo);
1259		goto out;
1260	}
1261
1262	pnfs_init_layoutreturn_args(&lrp->args, lo, stateid, iomode);
1263	lrp->args.ld_private = &lrp->ld_private;
1264	lrp->clp = NFS_SERVER(ino)->nfs_client;
1265	lrp->cred = cred;
1266	if (ld->prepare_layoutreturn)
1267		ld->prepare_layoutreturn(&lrp->args);
1268
1269	status = nfs4_proc_layoutreturn(lrp, sync);
1270out:
1271	dprintk("<-- %s status: %d\n", __func__, status);
1272	return status;
1273}
1274
1275static bool
1276pnfs_layout_segments_returnable(struct pnfs_layout_hdr *lo,
1277				enum pnfs_iomode iomode,
1278				u32 seq)
1279{
1280	struct pnfs_layout_range recall_range = {
1281		.length = NFS4_MAX_UINT64,
1282		.iomode = iomode,
1283	};
1284	return pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs,
1285					       &recall_range, seq) != -EBUSY;
1286}
1287
1288/* Return true if layoutreturn is needed */
1289static bool
1290pnfs_layout_need_return(struct pnfs_layout_hdr *lo)
1291{
 
 
1292	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1293		return false;
1294	return pnfs_layout_segments_returnable(lo, lo->plh_return_iomode,
1295					       lo->plh_return_seq);
 
 
 
 
 
 
1296}
1297
1298static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo)
1299{
1300	struct inode *inode= lo->plh_inode;
1301
1302	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1303		return;
1304	spin_lock(&inode->i_lock);
1305	if (pnfs_layout_need_return(lo)) {
1306		const struct cred *cred;
1307		nfs4_stateid stateid;
1308		enum pnfs_iomode iomode;
1309		bool send;
1310
1311		send = pnfs_prepare_layoutreturn(lo, &stateid, &cred, &iomode);
1312		spin_unlock(&inode->i_lock);
1313		if (send) {
1314			/* Send an async layoutreturn so we dont deadlock */
1315			pnfs_send_layoutreturn(lo, &stateid, &cred, iomode, false);
1316		}
1317	} else
1318		spin_unlock(&inode->i_lock);
1319}
1320
1321/*
1322 * Initiates a LAYOUTRETURN(FILE), and removes the pnfs_layout_hdr
1323 * when the layout segment list is empty.
1324 *
1325 * Note that a pnfs_layout_hdr can exist with an empty layout segment
1326 * list when LAYOUTGET has failed, or when LAYOUTGET succeeded, but the
1327 * deviceid is marked invalid.
1328 */
1329int
1330_pnfs_return_layout(struct inode *ino)
1331{
1332	struct pnfs_layout_hdr *lo = NULL;
1333	struct nfs_inode *nfsi = NFS_I(ino);
1334	struct pnfs_layout_range range = {
1335		.iomode		= IOMODE_ANY,
1336		.offset		= 0,
1337		.length		= NFS4_MAX_UINT64,
1338	};
1339	LIST_HEAD(tmp_list);
1340	const struct cred *cred;
1341	nfs4_stateid stateid;
1342	int status = 0;
1343	bool send, valid_layout;
1344
1345	dprintk("NFS: %s for inode %lu\n", __func__, ino->i_ino);
1346
1347	spin_lock(&ino->i_lock);
1348	lo = nfsi->layout;
1349	if (!lo) {
1350		spin_unlock(&ino->i_lock);
1351		dprintk("NFS: %s no layout to return\n", __func__);
1352		goto out;
1353	}
1354	/* Reference matched in nfs4_layoutreturn_release */
1355	pnfs_get_layout_hdr(lo);
1356	/* Is there an outstanding layoutreturn ? */
1357	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1358		spin_unlock(&ino->i_lock);
1359		if (wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1360					TASK_UNINTERRUPTIBLE))
1361			goto out_put_layout_hdr;
1362		spin_lock(&ino->i_lock);
1363	}
1364	valid_layout = pnfs_layout_is_valid(lo);
1365	pnfs_clear_layoutcommit(ino, &tmp_list);
1366	pnfs_mark_matching_lsegs_return(lo, &tmp_list, &range, 0);
1367
1368	if (NFS_SERVER(ino)->pnfs_curr_ld->return_range)
 
 
 
 
 
1369		NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo, &range);
 
1370
1371	/* Don't send a LAYOUTRETURN if list was initially empty */
1372	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) ||
1373			!valid_layout) {
1374		spin_unlock(&ino->i_lock);
1375		dprintk("NFS: %s no layout segments to return\n", __func__);
1376		goto out_wait_layoutreturn;
1377	}
1378
1379	send = pnfs_prepare_layoutreturn(lo, &stateid, &cred, NULL);
1380	spin_unlock(&ino->i_lock);
1381	if (send)
1382		status = pnfs_send_layoutreturn(lo, &stateid, &cred, IOMODE_ANY, true);
1383out_wait_layoutreturn:
1384	wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN, TASK_UNINTERRUPTIBLE);
1385out_put_layout_hdr:
1386	pnfs_free_lseg_list(&tmp_list);
1387	pnfs_put_layout_hdr(lo);
1388out:
1389	dprintk("<-- %s status: %d\n", __func__, status);
1390	return status;
1391}
1392
1393int
1394pnfs_commit_and_return_layout(struct inode *inode)
1395{
1396	struct pnfs_layout_hdr *lo;
1397	int ret;
1398
1399	spin_lock(&inode->i_lock);
1400	lo = NFS_I(inode)->layout;
1401	if (lo == NULL) {
1402		spin_unlock(&inode->i_lock);
1403		return 0;
1404	}
1405	pnfs_get_layout_hdr(lo);
1406	/* Block new layoutgets and read/write to ds */
1407	lo->plh_block_lgets++;
1408	spin_unlock(&inode->i_lock);
1409	filemap_fdatawait(inode->i_mapping);
1410	ret = pnfs_layoutcommit_inode(inode, true);
1411	if (ret == 0)
1412		ret = _pnfs_return_layout(inode);
1413	spin_lock(&inode->i_lock);
1414	lo->plh_block_lgets--;
1415	spin_unlock(&inode->i_lock);
1416	pnfs_put_layout_hdr(lo);
1417	return ret;
1418}
1419
1420bool pnfs_roc(struct inode *ino,
1421		struct nfs4_layoutreturn_args *args,
1422		struct nfs4_layoutreturn_res *res,
1423		const struct cred *cred)
1424{
1425	struct nfs_inode *nfsi = NFS_I(ino);
1426	struct nfs_open_context *ctx;
1427	struct nfs4_state *state;
1428	struct pnfs_layout_hdr *lo;
1429	struct pnfs_layout_segment *lseg, *next;
1430	const struct cred *lc_cred;
1431	nfs4_stateid stateid;
1432	enum pnfs_iomode iomode = 0;
1433	bool layoutreturn = false, roc = false;
1434	bool skip_read = false;
1435
1436	if (!nfs_have_layout(ino))
1437		return false;
1438retry:
1439	rcu_read_lock();
1440	spin_lock(&ino->i_lock);
1441	lo = nfsi->layout;
1442	if (!lo || !pnfs_layout_is_valid(lo) ||
1443	    test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1444		lo = NULL;
1445		goto out_noroc;
1446	}
1447	pnfs_get_layout_hdr(lo);
1448	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1449		spin_unlock(&ino->i_lock);
1450		rcu_read_unlock();
1451		wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1452				TASK_UNINTERRUPTIBLE);
1453		pnfs_put_layout_hdr(lo);
1454		goto retry;
1455	}
1456
1457	/* no roc if we hold a delegation */
1458	if (nfs4_check_delegation(ino, FMODE_READ)) {
1459		if (nfs4_check_delegation(ino, FMODE_WRITE))
1460			goto out_noroc;
1461		skip_read = true;
1462	}
1463
1464	list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
1465		state = ctx->state;
1466		if (state == NULL)
1467			continue;
1468		/* Don't return layout if there is open file state */
1469		if (state->state & FMODE_WRITE)
1470			goto out_noroc;
1471		if (state->state & FMODE_READ)
1472			skip_read = true;
1473	}
1474
1475
1476	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list) {
1477		if (skip_read && lseg->pls_range.iomode == IOMODE_READ)
1478			continue;
1479		/* If we are sending layoutreturn, invalidate all valid lsegs */
1480		if (!test_and_clear_bit(NFS_LSEG_ROC, &lseg->pls_flags))
1481			continue;
1482		/*
1483		 * Note: mark lseg for return so pnfs_layout_remove_lseg
1484		 * doesn't invalidate the layout for us.
1485		 */
1486		set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
1487		if (!mark_lseg_invalid(lseg, &lo->plh_return_segs))
1488			continue;
1489		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
1490	}
1491
1492	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1493		goto out_noroc;
1494
1495	/* ROC in two conditions:
1496	 * 1. there are ROC lsegs
1497	 * 2. we don't send layoutreturn
1498	 */
1499	/* lo ref dropped in pnfs_roc_release() */
1500	layoutreturn = pnfs_prepare_layoutreturn(lo, &stateid, &lc_cred, &iomode);
1501	/* If the creds don't match, we can't compound the layoutreturn */
1502	if (!layoutreturn || cred_fscmp(cred, lc_cred) != 0)
1503		goto out_noroc;
1504
1505	roc = layoutreturn;
1506	pnfs_init_layoutreturn_args(args, lo, &stateid, iomode);
1507	res->lrs_present = 0;
1508	layoutreturn = false;
1509	put_cred(lc_cred);
1510
1511out_noroc:
1512	spin_unlock(&ino->i_lock);
1513	rcu_read_unlock();
1514	pnfs_layoutcommit_inode(ino, true);
1515	if (roc) {
1516		struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1517		if (ld->prepare_layoutreturn)
1518			ld->prepare_layoutreturn(args);
1519		pnfs_put_layout_hdr(lo);
1520		return true;
1521	}
1522	if (layoutreturn)
1523		pnfs_send_layoutreturn(lo, &stateid, &lc_cred, iomode, true);
1524	pnfs_put_layout_hdr(lo);
1525	return false;
1526}
1527
1528int pnfs_roc_done(struct rpc_task *task, struct nfs4_layoutreturn_args **argpp,
1529		  struct nfs4_layoutreturn_res **respp, int *ret)
1530{
1531	struct nfs4_layoutreturn_args *arg = *argpp;
1532	int retval = -EAGAIN;
1533
1534	if (!arg)
1535		return 0;
1536	/* Handle Layoutreturn errors */
1537	switch (*ret) {
1538	case 0:
1539		retval = 0;
1540		break;
1541	case -NFS4ERR_NOMATCHING_LAYOUT:
1542		/* Was there an RPC level error? If not, retry */
1543		if (task->tk_rpc_status == 0)
1544			break;
1545		/* If the call was not sent, let caller handle it */
1546		if (!RPC_WAS_SENT(task))
1547			return 0;
1548		/*
1549		 * Otherwise, assume the call succeeded and
1550		 * that we need to release the layout
1551		 */
1552		*ret = 0;
1553		(*respp)->lrs_present = 0;
1554		retval = 0;
1555		break;
1556	case -NFS4ERR_DELAY:
1557		/* Let the caller handle the retry */
1558		*ret = -NFS4ERR_NOMATCHING_LAYOUT;
1559		return 0;
1560	case -NFS4ERR_OLD_STATEID:
1561		if (!nfs4_layout_refresh_old_stateid(&arg->stateid,
1562						     &arg->range, arg->inode))
1563			break;
1564		*ret = -NFS4ERR_NOMATCHING_LAYOUT;
1565		return -EAGAIN;
1566	}
1567	*argpp = NULL;
1568	*respp = NULL;
1569	return retval;
1570}
1571
1572void pnfs_roc_release(struct nfs4_layoutreturn_args *args,
1573		struct nfs4_layoutreturn_res *res,
1574		int ret)
1575{
1576	struct pnfs_layout_hdr *lo = args->layout;
1577	struct inode *inode = args->inode;
1578	const nfs4_stateid *res_stateid = NULL;
1579	struct nfs4_xdr_opaque_data *ld_private = args->ld_private;
1580
1581	switch (ret) {
1582	case -NFS4ERR_NOMATCHING_LAYOUT:
1583		spin_lock(&inode->i_lock);
1584		if (pnfs_layout_is_valid(lo) &&
1585		    nfs4_stateid_match_other(&args->stateid, &lo->plh_stateid))
1586			pnfs_set_plh_return_info(lo, args->range.iomode, 0);
1587		pnfs_clear_layoutreturn_waitbit(lo);
1588		spin_unlock(&inode->i_lock);
1589		break;
1590	case 0:
1591		if (res->lrs_present)
1592			res_stateid = &res->stateid;
1593		fallthrough;
1594	default:
1595		pnfs_layoutreturn_free_lsegs(lo, &args->stateid, &args->range,
1596					     res_stateid);
1597	}
1598	trace_nfs4_layoutreturn_on_close(args->inode, &args->stateid, ret);
 
1599	if (ld_private && ld_private->ops && ld_private->ops->free)
1600		ld_private->ops->free(ld_private);
1601	pnfs_put_layout_hdr(lo);
 
1602}
1603
1604bool pnfs_wait_on_layoutreturn(struct inode *ino, struct rpc_task *task)
1605{
1606	struct nfs_inode *nfsi = NFS_I(ino);
1607        struct pnfs_layout_hdr *lo;
1608        bool sleep = false;
1609
1610	/* we might not have grabbed lo reference. so need to check under
1611	 * i_lock */
1612        spin_lock(&ino->i_lock);
1613        lo = nfsi->layout;
1614        if (lo && test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
1615                rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
1616                sleep = true;
1617	}
1618        spin_unlock(&ino->i_lock);
1619        return sleep;
1620}
1621
1622/*
1623 * Compare two layout segments for sorting into layout cache.
1624 * We want to preferentially return RW over RO layouts, so ensure those
1625 * are seen first.
1626 */
1627static s64
1628pnfs_lseg_range_cmp(const struct pnfs_layout_range *l1,
1629	   const struct pnfs_layout_range *l2)
1630{
1631	s64 d;
1632
1633	/* high offset > low offset */
1634	d = l1->offset - l2->offset;
1635	if (d)
1636		return d;
1637
1638	/* short length > long length */
1639	d = l2->length - l1->length;
1640	if (d)
1641		return d;
1642
1643	/* read > read/write */
1644	return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
1645}
1646
1647static bool
1648pnfs_lseg_range_is_after(const struct pnfs_layout_range *l1,
1649		const struct pnfs_layout_range *l2)
1650{
1651	return pnfs_lseg_range_cmp(l1, l2) > 0;
1652}
1653
1654static bool
1655pnfs_lseg_no_merge(struct pnfs_layout_segment *lseg,
1656		struct pnfs_layout_segment *old)
1657{
1658	return false;
1659}
1660
1661void
1662pnfs_generic_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1663		   struct pnfs_layout_segment *lseg,
1664		   bool (*is_after)(const struct pnfs_layout_range *,
1665			   const struct pnfs_layout_range *),
1666		   bool (*do_merge)(struct pnfs_layout_segment *,
1667			   struct pnfs_layout_segment *),
1668		   struct list_head *free_me)
1669{
1670	struct pnfs_layout_segment *lp, *tmp;
1671
1672	dprintk("%s:Begin\n", __func__);
1673
1674	list_for_each_entry_safe(lp, tmp, &lo->plh_segs, pls_list) {
1675		if (test_bit(NFS_LSEG_VALID, &lp->pls_flags) == 0)
1676			continue;
1677		if (do_merge(lseg, lp)) {
1678			mark_lseg_invalid(lp, free_me);
1679			continue;
1680		}
1681		if (is_after(&lseg->pls_range, &lp->pls_range))
1682			continue;
1683		list_add_tail(&lseg->pls_list, &lp->pls_list);
1684		dprintk("%s: inserted lseg %p "
1685			"iomode %d offset %llu length %llu before "
1686			"lp %p iomode %d offset %llu length %llu\n",
1687			__func__, lseg, lseg->pls_range.iomode,
1688			lseg->pls_range.offset, lseg->pls_range.length,
1689			lp, lp->pls_range.iomode, lp->pls_range.offset,
1690			lp->pls_range.length);
1691		goto out;
1692	}
1693	list_add_tail(&lseg->pls_list, &lo->plh_segs);
1694	dprintk("%s: inserted lseg %p "
1695		"iomode %d offset %llu length %llu at tail\n",
1696		__func__, lseg, lseg->pls_range.iomode,
1697		lseg->pls_range.offset, lseg->pls_range.length);
1698out:
1699	pnfs_get_layout_hdr(lo);
1700
1701	dprintk("%s:Return\n", __func__);
1702}
1703EXPORT_SYMBOL_GPL(pnfs_generic_layout_insert_lseg);
1704
1705static void
1706pnfs_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1707		   struct pnfs_layout_segment *lseg,
1708		   struct list_head *free_me)
1709{
1710	struct inode *inode = lo->plh_inode;
1711	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
1712
1713	if (ld->add_lseg != NULL)
1714		ld->add_lseg(lo, lseg, free_me);
1715	else
1716		pnfs_generic_layout_insert_lseg(lo, lseg,
1717				pnfs_lseg_range_is_after,
1718				pnfs_lseg_no_merge,
1719				free_me);
1720}
1721
1722static struct pnfs_layout_hdr *
1723alloc_init_layout_hdr(struct inode *ino,
1724		      struct nfs_open_context *ctx,
1725		      gfp_t gfp_flags)
1726{
1727	struct pnfs_layout_hdr *lo;
1728
1729	lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
1730	if (!lo)
1731		return NULL;
1732	refcount_set(&lo->plh_refcount, 1);
1733	INIT_LIST_HEAD(&lo->plh_layouts);
1734	INIT_LIST_HEAD(&lo->plh_segs);
1735	INIT_LIST_HEAD(&lo->plh_return_segs);
1736	INIT_LIST_HEAD(&lo->plh_bulk_destroy);
1737	lo->plh_inode = ino;
1738	lo->plh_lc_cred = get_cred(ctx->cred);
1739	lo->plh_flags |= 1 << NFS_LAYOUT_INVALID_STID;
1740	return lo;
1741}
1742
1743static struct pnfs_layout_hdr *
1744pnfs_find_alloc_layout(struct inode *ino,
1745		       struct nfs_open_context *ctx,
1746		       gfp_t gfp_flags)
1747	__releases(&ino->i_lock)
1748	__acquires(&ino->i_lock)
1749{
1750	struct nfs_inode *nfsi = NFS_I(ino);
1751	struct pnfs_layout_hdr *new = NULL;
1752
1753	dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
1754
1755	if (nfsi->layout != NULL)
1756		goto out_existing;
1757	spin_unlock(&ino->i_lock);
1758	new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
1759	spin_lock(&ino->i_lock);
1760
1761	if (likely(nfsi->layout == NULL)) {	/* Won the race? */
1762		nfsi->layout = new;
1763		return new;
1764	} else if (new != NULL)
1765		pnfs_free_layout_hdr(new);
1766out_existing:
1767	pnfs_get_layout_hdr(nfsi->layout);
1768	return nfsi->layout;
1769}
1770
1771/*
1772 * iomode matching rules:
1773 * iomode	lseg	strict match
1774 *                      iomode
1775 * -----	-----	------ -----
1776 * ANY		READ	N/A    true
1777 * ANY		RW	N/A    true
1778 * RW		READ	N/A    false
1779 * RW		RW	N/A    true
1780 * READ		READ	N/A    true
1781 * READ		RW	true   false
1782 * READ		RW	false  true
1783 */
1784static bool
1785pnfs_lseg_range_match(const struct pnfs_layout_range *ls_range,
1786		 const struct pnfs_layout_range *range,
1787		 bool strict_iomode)
1788{
1789	struct pnfs_layout_range range1;
1790
1791	if ((range->iomode == IOMODE_RW &&
1792	     ls_range->iomode != IOMODE_RW) ||
1793	    (range->iomode != ls_range->iomode &&
1794	     strict_iomode) ||
1795	    !pnfs_lseg_range_intersecting(ls_range, range))
1796		return false;
1797
1798	/* range1 covers only the first byte in the range */
1799	range1 = *range;
1800	range1.length = 1;
1801	return pnfs_lseg_range_contained(ls_range, &range1);
1802}
1803
1804/*
1805 * lookup range in layout
1806 */
1807static struct pnfs_layout_segment *
1808pnfs_find_lseg(struct pnfs_layout_hdr *lo,
1809		struct pnfs_layout_range *range,
1810		bool strict_iomode)
1811{
1812	struct pnfs_layout_segment *lseg, *ret = NULL;
1813
1814	dprintk("%s:Begin\n", __func__);
1815
1816	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
1817		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
 
1818		    pnfs_lseg_range_match(&lseg->pls_range, range,
1819					  strict_iomode)) {
1820			ret = pnfs_get_lseg(lseg);
1821			break;
1822		}
1823	}
1824
1825	dprintk("%s:Return lseg %p ref %d\n",
1826		__func__, ret, ret ? refcount_read(&ret->pls_refcount) : 0);
1827	return ret;
1828}
1829
1830/*
1831 * Use mdsthreshold hints set at each OPEN to determine if I/O should go
1832 * to the MDS or over pNFS
1833 *
1834 * The nfs_inode read_io and write_io fields are cumulative counters reset
1835 * when there are no layout segments. Note that in pnfs_update_layout iomode
1836 * is set to IOMODE_READ for a READ request, and set to IOMODE_RW for a
1837 * WRITE request.
1838 *
1839 * A return of true means use MDS I/O.
1840 *
1841 * From rfc 5661:
1842 * If a file's size is smaller than the file size threshold, data accesses
1843 * SHOULD be sent to the metadata server.  If an I/O request has a length that
1844 * is below the I/O size threshold, the I/O SHOULD be sent to the metadata
1845 * server.  If both file size and I/O size are provided, the client SHOULD
1846 * reach or exceed  both thresholds before sending its read or write
1847 * requests to the data server.
1848 */
1849static bool pnfs_within_mdsthreshold(struct nfs_open_context *ctx,
1850				     struct inode *ino, int iomode)
1851{
1852	struct nfs4_threshold *t = ctx->mdsthreshold;
1853	struct nfs_inode *nfsi = NFS_I(ino);
1854	loff_t fsize = i_size_read(ino);
1855	bool size = false, size_set = false, io = false, io_set = false, ret = false;
1856
1857	if (t == NULL)
1858		return ret;
1859
1860	dprintk("%s bm=0x%x rd_sz=%llu wr_sz=%llu rd_io=%llu wr_io=%llu\n",
1861		__func__, t->bm, t->rd_sz, t->wr_sz, t->rd_io_sz, t->wr_io_sz);
1862
1863	switch (iomode) {
1864	case IOMODE_READ:
1865		if (t->bm & THRESHOLD_RD) {
1866			dprintk("%s fsize %llu\n", __func__, fsize);
1867			size_set = true;
1868			if (fsize < t->rd_sz)
1869				size = true;
1870		}
1871		if (t->bm & THRESHOLD_RD_IO) {
1872			dprintk("%s nfsi->read_io %llu\n", __func__,
1873				nfsi->read_io);
1874			io_set = true;
1875			if (nfsi->read_io < t->rd_io_sz)
1876				io = true;
1877		}
1878		break;
1879	case IOMODE_RW:
1880		if (t->bm & THRESHOLD_WR) {
1881			dprintk("%s fsize %llu\n", __func__, fsize);
1882			size_set = true;
1883			if (fsize < t->wr_sz)
1884				size = true;
1885		}
1886		if (t->bm & THRESHOLD_WR_IO) {
1887			dprintk("%s nfsi->write_io %llu\n", __func__,
1888				nfsi->write_io);
1889			io_set = true;
1890			if (nfsi->write_io < t->wr_io_sz)
1891				io = true;
1892		}
1893		break;
1894	}
1895	if (size_set && io_set) {
1896		if (size && io)
1897			ret = true;
1898	} else if (size || io)
1899		ret = true;
1900
1901	dprintk("<-- %s size %d io %d ret %d\n", __func__, size, io, ret);
1902	return ret;
1903}
1904
1905static int pnfs_prepare_to_retry_layoutget(struct pnfs_layout_hdr *lo)
1906{
1907	/*
1908	 * send layoutcommit as it can hold up layoutreturn due to lseg
1909	 * reference
1910	 */
1911	pnfs_layoutcommit_inode(lo->plh_inode, false);
1912	return wait_on_bit_action(&lo->plh_flags, NFS_LAYOUT_RETURN,
1913				   nfs_wait_bit_killable,
1914				   TASK_KILLABLE|TASK_FREEZABLE_UNSAFE);
1915}
1916
1917static void nfs_layoutget_begin(struct pnfs_layout_hdr *lo)
1918{
1919	atomic_inc(&lo->plh_outstanding);
1920}
1921
1922static void nfs_layoutget_end(struct pnfs_layout_hdr *lo)
1923{
1924	if (atomic_dec_and_test(&lo->plh_outstanding) &&
1925	    test_and_clear_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags))
1926		wake_up_bit(&lo->plh_flags, NFS_LAYOUT_DRAIN);
1927}
1928
1929static bool pnfs_is_first_layoutget(struct pnfs_layout_hdr *lo)
1930{
1931	return test_bit(NFS_LAYOUT_FIRST_LAYOUTGET, &lo->plh_flags);
1932}
1933
1934static void pnfs_clear_first_layoutget(struct pnfs_layout_hdr *lo)
1935{
1936	unsigned long *bitlock = &lo->plh_flags;
1937
1938	clear_bit_unlock(NFS_LAYOUT_FIRST_LAYOUTGET, bitlock);
1939	smp_mb__after_atomic();
1940	wake_up_bit(bitlock, NFS_LAYOUT_FIRST_LAYOUTGET);
1941}
1942
1943static void _add_to_server_list(struct pnfs_layout_hdr *lo,
1944				struct nfs_server *server)
1945{
1946	if (!test_and_set_bit(NFS_LAYOUT_HASHED, &lo->plh_flags)) {
1947		struct nfs_client *clp = server->nfs_client;
1948
1949		/* The lo must be on the clp list if there is any
1950		 * chance of a CB_LAYOUTRECALL(FILE) coming in.
1951		 */
1952		spin_lock(&clp->cl_lock);
1953		list_add_tail_rcu(&lo->plh_layouts, &server->layouts);
1954		spin_unlock(&clp->cl_lock);
1955	}
1956}
1957
1958/*
1959 * Layout segment is retreived from the server if not cached.
1960 * The appropriate layout segment is referenced and returned to the caller.
1961 */
1962struct pnfs_layout_segment *
1963pnfs_update_layout(struct inode *ino,
1964		   struct nfs_open_context *ctx,
1965		   loff_t pos,
1966		   u64 count,
1967		   enum pnfs_iomode iomode,
1968		   bool strict_iomode,
1969		   gfp_t gfp_flags)
1970{
1971	struct pnfs_layout_range arg = {
1972		.iomode = iomode,
1973		.offset = pos,
1974		.length = count,
1975	};
1976	unsigned pg_offset;
1977	struct nfs_server *server = NFS_SERVER(ino);
1978	struct nfs_client *clp = server->nfs_client;
1979	struct pnfs_layout_hdr *lo = NULL;
1980	struct pnfs_layout_segment *lseg = NULL;
1981	struct nfs4_layoutget *lgp;
1982	nfs4_stateid stateid;
1983	long timeout = 0;
1984	unsigned long giveup = jiffies + (clp->cl_lease_time << 1);
1985	bool first;
1986
1987	if (!pnfs_enabled_sb(NFS_SERVER(ino))) {
1988		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1989				 PNFS_UPDATE_LAYOUT_NO_PNFS);
1990		goto out;
1991	}
1992
 
 
 
 
 
 
1993	if (pnfs_within_mdsthreshold(ctx, ino, iomode)) {
1994		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1995				 PNFS_UPDATE_LAYOUT_MDSTHRESH);
1996		goto out;
1997	}
1998
1999lookup_again:
2000	lseg = ERR_PTR(nfs4_client_recover_expired_lease(clp));
2001	if (IS_ERR(lseg))
2002		goto out;
2003	first = false;
2004	spin_lock(&ino->i_lock);
2005	lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
2006	if (lo == NULL) {
2007		spin_unlock(&ino->i_lock);
2008		lseg = ERR_PTR(-ENOMEM);
2009		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2010				 PNFS_UPDATE_LAYOUT_NOMEM);
2011		goto out;
2012	}
2013
2014	/* Do we even need to bother with this? */
2015	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
2016		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2017				 PNFS_UPDATE_LAYOUT_BULK_RECALL);
2018		dprintk("%s matches recall, use MDS\n", __func__);
2019		goto out_unlock;
2020	}
2021
2022	/* if LAYOUTGET already failed once we don't try again */
2023	if (pnfs_layout_io_test_failed(lo, iomode)) {
2024		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2025				 PNFS_UPDATE_LAYOUT_IO_TEST_FAIL);
2026		goto out_unlock;
2027	}
2028
2029	/*
2030	 * If the layout segment list is empty, but there are outstanding
2031	 * layoutget calls, then they might be subject to a layoutrecall.
2032	 */
2033	if (test_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags) &&
2034	    atomic_read(&lo->plh_outstanding) != 0) {
2035		spin_unlock(&ino->i_lock);
2036		lseg = ERR_PTR(wait_on_bit(&lo->plh_flags, NFS_LAYOUT_DRAIN,
2037					   TASK_KILLABLE));
2038		if (IS_ERR(lseg))
2039			goto out_put_layout_hdr;
2040		pnfs_put_layout_hdr(lo);
2041		goto lookup_again;
2042	}
2043
2044	/*
2045	 * Because we free lsegs when sending LAYOUTRETURN, we need to wait
2046	 * for LAYOUTRETURN.
2047	 */
2048	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
2049		spin_unlock(&ino->i_lock);
2050		dprintk("%s wait for layoutreturn\n", __func__);
2051		lseg = ERR_PTR(pnfs_prepare_to_retry_layoutget(lo));
2052		if (!IS_ERR(lseg)) {
2053			pnfs_put_layout_hdr(lo);
2054			dprintk("%s retrying\n", __func__);
2055			trace_pnfs_update_layout(ino, pos, count, iomode, lo,
2056						 lseg,
2057						 PNFS_UPDATE_LAYOUT_RETRY);
2058			goto lookup_again;
2059		}
2060		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2061					 PNFS_UPDATE_LAYOUT_RETURN);
2062		goto out_put_layout_hdr;
2063	}
2064
2065	lseg = pnfs_find_lseg(lo, &arg, strict_iomode);
2066	if (lseg) {
2067		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2068				PNFS_UPDATE_LAYOUT_FOUND_CACHED);
2069		goto out_unlock;
2070	}
2071
2072	/*
2073	 * Choose a stateid for the LAYOUTGET. If we don't have a layout
2074	 * stateid, or it has been invalidated, then we must use the open
2075	 * stateid.
2076	 */
2077	if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags)) {
2078		int status;
2079
2080		/*
2081		 * The first layoutget for the file. Need to serialize per
2082		 * RFC 5661 Errata 3208.
2083		 */
2084		if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET,
2085				     &lo->plh_flags)) {
2086			spin_unlock(&ino->i_lock);
2087			lseg = ERR_PTR(wait_on_bit(&lo->plh_flags,
2088						NFS_LAYOUT_FIRST_LAYOUTGET,
2089						TASK_KILLABLE));
2090			if (IS_ERR(lseg))
2091				goto out_put_layout_hdr;
2092			pnfs_put_layout_hdr(lo);
2093			dprintk("%s retrying\n", __func__);
2094			goto lookup_again;
2095		}
2096
2097		spin_unlock(&ino->i_lock);
2098		first = true;
2099		status = nfs4_select_rw_stateid(ctx->state,
2100					iomode == IOMODE_RW ? FMODE_WRITE : FMODE_READ,
2101					NULL, &stateid, NULL);
2102		if (status != 0) {
2103			lseg = ERR_PTR(status);
2104			trace_pnfs_update_layout(ino, pos, count,
2105					iomode, lo, lseg,
2106					PNFS_UPDATE_LAYOUT_INVALID_OPEN);
2107			nfs4_schedule_stateid_recovery(server, ctx->state);
2108			pnfs_clear_first_layoutget(lo);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2109			pnfs_put_layout_hdr(lo);
 
 
 
2110			goto lookup_again;
2111		}
2112		spin_lock(&ino->i_lock);
2113	} else {
2114		nfs4_stateid_copy(&stateid, &lo->plh_stateid);
2115	}
2116
2117	if (pnfs_layoutgets_blocked(lo)) {
2118		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2119				PNFS_UPDATE_LAYOUT_BLOCKED);
2120		goto out_unlock;
2121	}
2122	nfs_layoutget_begin(lo);
2123	spin_unlock(&ino->i_lock);
2124
2125	_add_to_server_list(lo, server);
 
 
 
 
 
 
 
 
2126
2127	pg_offset = arg.offset & ~PAGE_MASK;
2128	if (pg_offset) {
2129		arg.offset -= pg_offset;
2130		arg.length += pg_offset;
2131	}
2132	if (arg.length != NFS4_MAX_UINT64)
2133		arg.length = PAGE_ALIGN(arg.length);
2134
2135	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &stateid, &arg, gfp_flags);
2136	if (!lgp) {
2137		lseg = ERR_PTR(-ENOMEM);
2138		trace_pnfs_update_layout(ino, pos, count, iomode, lo, NULL,
2139					 PNFS_UPDATE_LAYOUT_NOMEM);
2140		nfs_layoutget_end(lo);
2141		goto out_put_layout_hdr;
2142	}
2143
2144	lgp->lo = lo;
2145	pnfs_get_layout_hdr(lo);
2146
2147	lseg = nfs4_proc_layoutget(lgp, &timeout);
2148	trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2149				 PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET);
2150	nfs_layoutget_end(lo);
2151	if (IS_ERR(lseg)) {
2152		switch(PTR_ERR(lseg)) {
2153		case -EBUSY:
2154			if (time_after(jiffies, giveup))
2155				lseg = NULL;
2156			break;
2157		case -ERECALLCONFLICT:
 
 
 
 
 
 
 
 
 
2158		case -EAGAIN:
2159			break;
2160		case -ENODATA:
2161			/* The server returned NFS4ERR_LAYOUTUNAVAILABLE */
2162			pnfs_layout_set_fail_bit(
2163				lo, pnfs_iomode_to_fail_bit(iomode));
2164			lseg = NULL;
2165			goto out_put_layout_hdr;
2166		default:
2167			if (!nfs_error_is_fatal(PTR_ERR(lseg))) {
2168				pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2169				lseg = NULL;
2170			}
2171			goto out_put_layout_hdr;
2172		}
2173		if (lseg) {
2174			if (first)
2175				pnfs_clear_first_layoutget(lo);
2176			trace_pnfs_update_layout(ino, pos, count,
2177				iomode, lo, lseg, PNFS_UPDATE_LAYOUT_RETRY);
2178			pnfs_put_layout_hdr(lo);
2179			goto lookup_again;
2180		}
2181	} else {
2182		pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2183	}
2184
2185out_put_layout_hdr:
2186	if (first)
2187		pnfs_clear_first_layoutget(lo);
2188	trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2189				 PNFS_UPDATE_LAYOUT_EXIT);
2190	pnfs_put_layout_hdr(lo);
2191out:
2192	dprintk("%s: inode %s/%llu pNFS layout segment %s for "
2193			"(%s, offset: %llu, length: %llu)\n",
2194			__func__, ino->i_sb->s_id,
2195			(unsigned long long)NFS_FILEID(ino),
2196			IS_ERR_OR_NULL(lseg) ? "not found" : "found",
2197			iomode==IOMODE_RW ?  "read/write" : "read-only",
2198			(unsigned long long)pos,
2199			(unsigned long long)count);
2200	return lseg;
2201out_unlock:
2202	spin_unlock(&ino->i_lock);
2203	goto out_put_layout_hdr;
2204}
2205EXPORT_SYMBOL_GPL(pnfs_update_layout);
2206
2207static bool
2208pnfs_sanity_check_layout_range(struct pnfs_layout_range *range)
2209{
2210	switch (range->iomode) {
2211	case IOMODE_READ:
2212	case IOMODE_RW:
2213		break;
2214	default:
2215		return false;
2216	}
2217	if (range->offset == NFS4_MAX_UINT64)
2218		return false;
2219	if (range->length == 0)
2220		return false;
2221	if (range->length != NFS4_MAX_UINT64 &&
2222	    range->length > NFS4_MAX_UINT64 - range->offset)
2223		return false;
2224	return true;
2225}
2226
2227static struct pnfs_layout_hdr *
2228_pnfs_grab_empty_layout(struct inode *ino, struct nfs_open_context *ctx)
2229{
2230	struct pnfs_layout_hdr *lo;
2231
2232	spin_lock(&ino->i_lock);
2233	lo = pnfs_find_alloc_layout(ino, ctx, nfs_io_gfp_mask());
2234	if (!lo)
2235		goto out_unlock;
2236	if (!test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags))
2237		goto out_unlock;
2238	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
2239		goto out_unlock;
2240	if (pnfs_layoutgets_blocked(lo))
2241		goto out_unlock;
2242	if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET, &lo->plh_flags))
2243		goto out_unlock;
2244	nfs_layoutget_begin(lo);
2245	spin_unlock(&ino->i_lock);
2246	_add_to_server_list(lo, NFS_SERVER(ino));
2247	return lo;
2248
2249out_unlock:
2250	spin_unlock(&ino->i_lock);
2251	pnfs_put_layout_hdr(lo);
2252	return NULL;
2253}
2254
2255static void _lgopen_prepare_attached(struct nfs4_opendata *data,
2256				     struct nfs_open_context *ctx)
2257{
2258	struct inode *ino = data->dentry->d_inode;
2259	struct pnfs_layout_range rng = {
2260		.iomode = (data->o_arg.fmode & FMODE_WRITE) ?
2261			  IOMODE_RW: IOMODE_READ,
2262		.offset = 0,
2263		.length = NFS4_MAX_UINT64,
2264	};
2265	struct nfs4_layoutget *lgp;
2266	struct pnfs_layout_hdr *lo;
2267
2268	/* Heuristic: don't send layoutget if we have cached data */
2269	if (rng.iomode == IOMODE_READ &&
2270	   (i_size_read(ino) == 0 || ino->i_mapping->nrpages != 0))
2271		return;
2272
2273	lo = _pnfs_grab_empty_layout(ino, ctx);
2274	if (!lo)
2275		return;
2276	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &current_stateid, &rng,
2277					     nfs_io_gfp_mask());
2278	if (!lgp) {
2279		pnfs_clear_first_layoutget(lo);
2280		nfs_layoutget_end(lo);
2281		pnfs_put_layout_hdr(lo);
2282		return;
2283	}
2284	lgp->lo = lo;
2285	data->lgp = lgp;
2286	data->o_arg.lg_args = &lgp->args;
2287	data->o_res.lg_res = &lgp->res;
2288}
2289
2290static void _lgopen_prepare_floating(struct nfs4_opendata *data,
2291				     struct nfs_open_context *ctx)
2292{
2293	struct inode *ino = data->dentry->d_inode;
2294	struct pnfs_layout_range rng = {
2295		.iomode = (data->o_arg.fmode & FMODE_WRITE) ?
2296			  IOMODE_RW: IOMODE_READ,
2297		.offset = 0,
2298		.length = NFS4_MAX_UINT64,
2299	};
2300	struct nfs4_layoutget *lgp;
2301
2302	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &current_stateid, &rng,
2303					     nfs_io_gfp_mask());
2304	if (!lgp)
2305		return;
2306	data->lgp = lgp;
2307	data->o_arg.lg_args = &lgp->args;
2308	data->o_res.lg_res = &lgp->res;
2309}
2310
2311void pnfs_lgopen_prepare(struct nfs4_opendata *data,
2312			 struct nfs_open_context *ctx)
2313{
2314	struct nfs_server *server = NFS_SERVER(data->dir->d_inode);
2315
2316	if (!(pnfs_enabled_sb(server) &&
2317	      server->pnfs_curr_ld->flags & PNFS_LAYOUTGET_ON_OPEN))
2318		return;
2319	/* Could check on max_ops, but currently hardcoded high enough */
2320	if (!nfs_server_capable(data->dir->d_inode, NFS_CAP_LGOPEN))
2321		return;
2322	if (data->lgp)
2323		return;
2324	if (data->state)
2325		_lgopen_prepare_attached(data, ctx);
2326	else
2327		_lgopen_prepare_floating(data, ctx);
2328}
2329
2330void pnfs_parse_lgopen(struct inode *ino, struct nfs4_layoutget *lgp,
2331		       struct nfs_open_context *ctx)
2332{
2333	struct pnfs_layout_hdr *lo;
2334	struct pnfs_layout_segment *lseg;
2335	struct nfs_server *srv = NFS_SERVER(ino);
2336	u32 iomode;
2337
2338	if (!lgp)
2339		return;
2340	dprintk("%s: entered with status %i\n", __func__, lgp->res.status);
2341	if (lgp->res.status) {
2342		switch (lgp->res.status) {
2343		default:
2344			break;
2345		/*
2346		 * Halt lgopen attempts if the server doesn't recognise
2347		 * the "current stateid" value, the layout type, or the
2348		 * layoutget operation as being valid.
2349		 * Also if it complains about too many ops in the compound
2350		 * or of the request/reply being too big.
2351		 */
2352		case -NFS4ERR_BAD_STATEID:
2353		case -NFS4ERR_NOTSUPP:
2354		case -NFS4ERR_REP_TOO_BIG:
2355		case -NFS4ERR_REP_TOO_BIG_TO_CACHE:
2356		case -NFS4ERR_REQ_TOO_BIG:
2357		case -NFS4ERR_TOO_MANY_OPS:
2358		case -NFS4ERR_UNKNOWN_LAYOUTTYPE:
2359			srv->caps &= ~NFS_CAP_LGOPEN;
2360		}
2361		return;
2362	}
2363	if (!lgp->lo) {
2364		lo = _pnfs_grab_empty_layout(ino, ctx);
2365		if (!lo)
2366			return;
2367		lgp->lo = lo;
2368	} else
2369		lo = lgp->lo;
2370
2371	lseg = pnfs_layout_process(lgp);
2372	if (!IS_ERR(lseg)) {
2373		iomode = lgp->args.range.iomode;
2374		pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2375		pnfs_put_lseg(lseg);
2376	}
2377}
2378
2379void nfs4_lgopen_release(struct nfs4_layoutget *lgp)
2380{
2381	if (lgp != NULL) {
2382		if (lgp->lo) {
2383			pnfs_clear_first_layoutget(lgp->lo);
2384			nfs_layoutget_end(lgp->lo);
2385		}
2386		pnfs_layoutget_free(lgp);
2387	}
2388}
2389
2390struct pnfs_layout_segment *
2391pnfs_layout_process(struct nfs4_layoutget *lgp)
2392{
2393	struct pnfs_layout_hdr *lo = lgp->lo;
2394	struct nfs4_layoutget_res *res = &lgp->res;
2395	struct pnfs_layout_segment *lseg;
2396	struct inode *ino = lo->plh_inode;
2397	LIST_HEAD(free_me);
2398
2399	if (!pnfs_sanity_check_layout_range(&res->range))
2400		return ERR_PTR(-EINVAL);
2401
2402	/* Inject layout blob into I/O device driver */
2403	lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
2404	if (IS_ERR_OR_NULL(lseg)) {
2405		if (!lseg)
2406			lseg = ERR_PTR(-ENOMEM);
2407
2408		dprintk("%s: Could not allocate layout: error %ld\n",
2409		       __func__, PTR_ERR(lseg));
2410		return lseg;
2411	}
2412
2413	pnfs_init_lseg(lo, lseg, &res->range, &res->stateid);
2414
2415	spin_lock(&ino->i_lock);
2416	if (pnfs_layoutgets_blocked(lo)) {
2417		dprintk("%s forget reply due to state\n", __func__);
2418		goto out_forget;
2419	}
2420
2421	if (test_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags) &&
2422	    !pnfs_is_first_layoutget(lo))
2423		goto out_forget;
2424
2425	if (nfs4_stateid_match_other(&lo->plh_stateid, &res->stateid)) {
2426		/* existing state ID, make sure the sequence number matches. */
2427		if (pnfs_layout_stateid_blocked(lo, &res->stateid)) {
2428			if (!pnfs_layout_is_valid(lo))
2429				lo->plh_barrier = 0;
2430			dprintk("%s forget reply due to sequence\n", __func__);
2431			goto out_forget;
2432		}
2433		pnfs_set_layout_stateid(lo, &res->stateid, lgp->cred, false);
2434	} else if (pnfs_layout_is_valid(lo)) {
2435		/*
2436		 * We got an entirely new state ID.  Mark all segments for the
2437		 * inode invalid, and retry the layoutget
2438		 */
2439		struct pnfs_layout_range range = {
2440			.iomode = IOMODE_ANY,
2441			.length = NFS4_MAX_UINT64,
2442		};
2443		pnfs_mark_matching_lsegs_return(lo, &free_me, &range, 0);
2444		goto out_forget;
2445	} else {
2446		/* We have a completely new layout */
2447		pnfs_set_layout_stateid(lo, &res->stateid, lgp->cred, true);
2448	}
2449
2450	pnfs_get_lseg(lseg);
2451	pnfs_layout_insert_lseg(lo, lseg, &free_me);
2452
2453
2454	if (res->return_on_close)
2455		set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
2456
2457	spin_unlock(&ino->i_lock);
2458	pnfs_free_lseg_list(&free_me);
2459	return lseg;
2460
2461out_forget:
2462	spin_unlock(&ino->i_lock);
2463	lseg->pls_layout = lo;
2464	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
 
 
2465	return ERR_PTR(-EAGAIN);
2466}
2467
2468/**
2469 * pnfs_mark_matching_lsegs_return - Free or return matching layout segments
2470 * @lo: pointer to layout header
2471 * @tmp_list: list header to be used with pnfs_free_lseg_list()
2472 * @return_range: describe layout segment ranges to be returned
2473 * @seq: stateid seqid to match
2474 *
2475 * This function is mainly intended for use by layoutrecall. It attempts
2476 * to free the layout segment immediately, or else to mark it for return
2477 * as soon as its reference count drops to zero.
2478 *
2479 * Returns
2480 * - 0: a layoutreturn needs to be scheduled.
2481 * - EBUSY: there are layout segment that are still in use.
2482 * - ENOENT: there are no layout segments that need to be returned.
2483 */
2484int
2485pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
2486				struct list_head *tmp_list,
2487				const struct pnfs_layout_range *return_range,
2488				u32 seq)
2489{
2490	struct pnfs_layout_segment *lseg, *next;
2491	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
2492	int remaining = 0;
2493
2494	dprintk("%s:Begin lo %p\n", __func__, lo);
2495
 
 
 
2496	assert_spin_locked(&lo->plh_inode->i_lock);
2497
2498	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
2499		tmp_list = &lo->plh_return_segs;
2500
2501	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
2502		if (pnfs_match_lseg_recall(lseg, return_range, seq)) {
2503			dprintk("%s: marking lseg %p iomode %d "
2504				"offset %llu length %llu\n", __func__,
2505				lseg, lseg->pls_range.iomode,
2506				lseg->pls_range.offset,
2507				lseg->pls_range.length);
2508			if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
2509				tmp_list = &lo->plh_return_segs;
2510			if (mark_lseg_invalid(lseg, tmp_list))
2511				continue;
2512			remaining++;
2513			set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
2514			pnfs_lseg_cancel_io(server, lseg);
2515		}
2516
2517	if (remaining) {
2518		pnfs_set_plh_return_info(lo, return_range->iomode, seq);
2519		return -EBUSY;
2520	}
2521
2522	if (!list_empty(&lo->plh_return_segs)) {
2523		pnfs_set_plh_return_info(lo, return_range->iomode, seq);
2524		return 0;
2525	}
2526
2527	return -ENOENT;
2528}
2529
2530static void
2531pnfs_mark_layout_for_return(struct inode *inode,
2532			    const struct pnfs_layout_range *range)
2533{
2534	struct pnfs_layout_hdr *lo;
 
 
 
 
 
2535	bool return_now = false;
2536
2537	spin_lock(&inode->i_lock);
2538	lo = NFS_I(inode)->layout;
2539	if (!pnfs_layout_is_valid(lo)) {
2540		spin_unlock(&inode->i_lock);
2541		return;
2542	}
2543	pnfs_set_plh_return_info(lo, range->iomode, 0);
2544	/*
2545	 * mark all matching lsegs so that we are sure to have no live
2546	 * segments at hand when sending layoutreturn. See pnfs_put_lseg()
2547	 * for how it works.
2548	 */
2549	if (pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs, range, 0) != -EBUSY) {
2550		const struct cred *cred;
2551		nfs4_stateid stateid;
2552		enum pnfs_iomode iomode;
2553
2554		return_now = pnfs_prepare_layoutreturn(lo, &stateid, &cred, &iomode);
2555		spin_unlock(&inode->i_lock);
2556		if (return_now)
2557			pnfs_send_layoutreturn(lo, &stateid, &cred, iomode, false);
2558	} else {
2559		spin_unlock(&inode->i_lock);
2560		nfs_commit_inode(inode, 0);
2561	}
2562}
2563
2564void pnfs_error_mark_layout_for_return(struct inode *inode,
2565				       struct pnfs_layout_segment *lseg)
2566{
2567	struct pnfs_layout_range range = {
2568		.iomode = lseg->pls_range.iomode,
2569		.offset = 0,
2570		.length = NFS4_MAX_UINT64,
2571	};
2572
2573	pnfs_mark_layout_for_return(inode, &range);
2574}
2575EXPORT_SYMBOL_GPL(pnfs_error_mark_layout_for_return);
2576
2577static bool
2578pnfs_layout_can_be_returned(struct pnfs_layout_hdr *lo)
2579{
2580	return pnfs_layout_is_valid(lo) &&
2581		!test_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags) &&
2582		!test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
2583}
2584
2585static struct pnfs_layout_segment *
2586pnfs_find_first_lseg(struct pnfs_layout_hdr *lo,
2587		     const struct pnfs_layout_range *range,
2588		     enum pnfs_iomode iomode)
2589{
2590	struct pnfs_layout_segment *lseg;
2591
2592	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
2593		if (!test_bit(NFS_LSEG_VALID, &lseg->pls_flags))
2594			continue;
2595		if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
2596			continue;
2597		if (lseg->pls_range.iomode != iomode && iomode != IOMODE_ANY)
2598			continue;
2599		if (pnfs_lseg_range_intersecting(&lseg->pls_range, range))
2600			return lseg;
2601	}
2602	return NULL;
2603}
2604
2605/* Find open file states whose mode matches that of the range */
2606static bool
2607pnfs_should_return_unused_layout(struct pnfs_layout_hdr *lo,
2608				 const struct pnfs_layout_range *range)
2609{
2610	struct list_head *head;
2611	struct nfs_open_context *ctx;
2612	fmode_t mode = 0;
2613
2614	if (!pnfs_layout_can_be_returned(lo) ||
2615	    !pnfs_find_first_lseg(lo, range, range->iomode))
2616		return false;
2617
2618	head = &NFS_I(lo->plh_inode)->open_files;
2619	list_for_each_entry_rcu(ctx, head, list) {
2620		if (ctx->state)
2621			mode |= ctx->state->state & (FMODE_READ|FMODE_WRITE);
2622	}
2623
2624	switch (range->iomode) {
2625	default:
2626		break;
2627	case IOMODE_READ:
2628		mode &= ~FMODE_WRITE;
2629		break;
2630	case IOMODE_RW:
2631		if (pnfs_find_first_lseg(lo, range, IOMODE_READ))
2632			mode &= ~FMODE_READ;
2633	}
2634	return mode == 0;
2635}
2636
2637static int
2638pnfs_layout_return_unused_byserver(struct nfs_server *server, void *data)
2639{
2640	const struct pnfs_layout_range *range = data;
2641	struct pnfs_layout_hdr *lo;
2642	struct inode *inode;
2643restart:
2644	rcu_read_lock();
2645	list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
2646		if (!pnfs_layout_can_be_returned(lo) ||
2647		    test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
2648			continue;
2649		inode = lo->plh_inode;
2650		spin_lock(&inode->i_lock);
2651		if (!pnfs_should_return_unused_layout(lo, range)) {
2652			spin_unlock(&inode->i_lock);
2653			continue;
2654		}
2655		spin_unlock(&inode->i_lock);
2656		inode = pnfs_grab_inode_layout_hdr(lo);
2657		if (!inode)
2658			continue;
2659		rcu_read_unlock();
2660		pnfs_mark_layout_for_return(inode, range);
2661		iput(inode);
2662		cond_resched();
2663		goto restart;
2664	}
2665	rcu_read_unlock();
2666	return 0;
2667}
2668
2669void
2670pnfs_layout_return_unused_byclid(struct nfs_client *clp,
2671				 enum pnfs_iomode iomode)
2672{
2673	struct pnfs_layout_range range = {
2674		.iomode = iomode,
2675		.offset = 0,
2676		.length = NFS4_MAX_UINT64,
2677	};
2678
2679	nfs_client_for_each_server(clp, pnfs_layout_return_unused_byserver,
2680			&range);
2681}
2682
2683void
2684pnfs_generic_pg_check_layout(struct nfs_pageio_descriptor *pgio)
2685{
2686	if (pgio->pg_lseg == NULL ||
2687	    test_bit(NFS_LSEG_VALID, &pgio->pg_lseg->pls_flags))
2688		return;
2689	pnfs_put_lseg(pgio->pg_lseg);
2690	pgio->pg_lseg = NULL;
2691}
2692EXPORT_SYMBOL_GPL(pnfs_generic_pg_check_layout);
2693
2694/*
2695 * Check for any intersection between the request and the pgio->pg_lseg,
2696 * and if none, put this pgio->pg_lseg away.
2697 */
2698void
2699pnfs_generic_pg_check_range(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
2700{
2701	if (pgio->pg_lseg && !pnfs_lseg_request_intersecting(pgio->pg_lseg, req)) {
2702		pnfs_put_lseg(pgio->pg_lseg);
2703		pgio->pg_lseg = NULL;
2704	}
2705}
2706EXPORT_SYMBOL_GPL(pnfs_generic_pg_check_range);
2707
2708void
2709pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
2710{
2711	u64 rd_size;
2712
2713	pnfs_generic_pg_check_layout(pgio);
2714	pnfs_generic_pg_check_range(pgio, req);
2715	if (pgio->pg_lseg == NULL) {
2716		if (pgio->pg_dreq == NULL)
2717			rd_size = i_size_read(pgio->pg_inode) - req_offset(req);
2718		else
2719			rd_size = nfs_dreq_bytes_left(pgio->pg_dreq);
2720
2721		pgio->pg_lseg =
2722			pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
2723					   req_offset(req), rd_size,
2724					   IOMODE_READ, false,
2725					   nfs_io_gfp_mask());
 
 
2726		if (IS_ERR(pgio->pg_lseg)) {
2727			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2728			pgio->pg_lseg = NULL;
2729			return;
2730		}
2731	}
2732	/* If no lseg, fall back to read through mds */
2733	if (pgio->pg_lseg == NULL)
2734		nfs_pageio_reset_read_mds(pgio);
2735
2736}
2737EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);
2738
2739void
2740pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
2741			   struct nfs_page *req, u64 wb_size)
2742{
2743	pnfs_generic_pg_check_layout(pgio);
2744	pnfs_generic_pg_check_range(pgio, req);
2745	if (pgio->pg_lseg == NULL) {
2746		pgio->pg_lseg =
2747			pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
2748					   req_offset(req), wb_size, IOMODE_RW,
2749					   false, nfs_io_gfp_mask());
 
 
 
2750		if (IS_ERR(pgio->pg_lseg)) {
2751			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2752			pgio->pg_lseg = NULL;
2753			return;
2754		}
2755	}
2756	/* If no lseg, fall back to write through mds */
2757	if (pgio->pg_lseg == NULL)
2758		nfs_pageio_reset_write_mds(pgio);
2759}
2760EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
2761
2762void
2763pnfs_generic_pg_cleanup(struct nfs_pageio_descriptor *desc)
2764{
2765	if (desc->pg_lseg) {
2766		pnfs_put_lseg(desc->pg_lseg);
2767		desc->pg_lseg = NULL;
2768	}
2769}
2770EXPORT_SYMBOL_GPL(pnfs_generic_pg_cleanup);
2771
2772/*
2773 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
2774 * of bytes (maximum @req->wb_bytes) that can be coalesced.
2775 */
2776size_t
2777pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio,
2778		     struct nfs_page *prev, struct nfs_page *req)
2779{
2780	unsigned int size;
2781	u64 seg_end, req_start, seg_left;
2782
2783	size = nfs_generic_pg_test(pgio, prev, req);
2784	if (!size)
2785		return 0;
2786
2787	/*
2788	 * 'size' contains the number of bytes left in the current page (up
2789	 * to the original size asked for in @req->wb_bytes).
2790	 *
2791	 * Calculate how many bytes are left in the layout segment
2792	 * and if there are less bytes than 'size', return that instead.
2793	 *
2794	 * Please also note that 'end_offset' is actually the offset of the
2795	 * first byte that lies outside the pnfs_layout_range. FIXME?
2796	 *
2797	 */
2798	if (pgio->pg_lseg) {
2799		seg_end = pnfs_end_offset(pgio->pg_lseg->pls_range.offset,
2800				     pgio->pg_lseg->pls_range.length);
2801		req_start = req_offset(req);
2802
2803		/* start of request is past the last byte of this segment */
2804		if (req_start >= seg_end)
2805			return 0;
2806
2807		/* adjust 'size' iff there are fewer bytes left in the
2808		 * segment than what nfs_generic_pg_test returned */
2809		seg_left = seg_end - req_start;
2810		if (seg_left < size)
2811			size = (unsigned int)seg_left;
2812	}
2813
2814	return size;
2815}
2816EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
2817
2818int pnfs_write_done_resend_to_mds(struct nfs_pgio_header *hdr)
2819{
2820	struct nfs_pageio_descriptor pgio;
2821
2822	/* Resend all requests through the MDS */
2823	nfs_pageio_init_write(&pgio, hdr->inode, FLUSH_STABLE, true,
2824			      hdr->completion_ops);
 
2825	return nfs_pageio_resend(&pgio, hdr);
2826}
2827EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
2828
2829static void pnfs_ld_handle_write_error(struct nfs_pgio_header *hdr)
2830{
2831
2832	dprintk("pnfs write error = %d\n", hdr->pnfs_error);
2833	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2834	    PNFS_LAYOUTRET_ON_ERROR) {
2835		pnfs_return_layout(hdr->inode);
2836	}
2837	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2838		hdr->task.tk_status = pnfs_write_done_resend_to_mds(hdr);
2839}
2840
2841/*
2842 * Called by non rpc-based layout drivers
2843 */
2844void pnfs_ld_write_done(struct nfs_pgio_header *hdr)
2845{
2846	if (likely(!hdr->pnfs_error)) {
2847		pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
2848				hdr->mds_offset + hdr->res.count);
2849		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
2850	}
2851	trace_nfs4_pnfs_write(hdr, hdr->pnfs_error);
2852	if (unlikely(hdr->pnfs_error))
2853		pnfs_ld_handle_write_error(hdr);
2854	hdr->mds_ops->rpc_release(hdr);
2855}
2856EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
2857
2858static void
2859pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
2860		struct nfs_pgio_header *hdr)
2861{
2862	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2863
2864	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2865		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
2866		nfs_pageio_reset_write_mds(desc);
2867		mirror->pg_recoalesce = 1;
2868	}
2869	hdr->completion_ops->completion(hdr);
2870}
2871
2872static enum pnfs_try_status
2873pnfs_try_to_write_data(struct nfs_pgio_header *hdr,
2874			const struct rpc_call_ops *call_ops,
2875			struct pnfs_layout_segment *lseg,
2876			int how)
2877{
2878	struct inode *inode = hdr->inode;
2879	enum pnfs_try_status trypnfs;
2880	struct nfs_server *nfss = NFS_SERVER(inode);
2881
2882	hdr->mds_ops = call_ops;
2883
2884	dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
2885		inode->i_ino, hdr->args.count, hdr->args.offset, how);
2886	trypnfs = nfss->pnfs_curr_ld->write_pagelist(hdr, how);
2887	if (trypnfs != PNFS_NOT_ATTEMPTED)
2888		nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
2889	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
2890	return trypnfs;
2891}
2892
2893static void
2894pnfs_do_write(struct nfs_pageio_descriptor *desc,
2895	      struct nfs_pgio_header *hdr, int how)
2896{
2897	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
2898	struct pnfs_layout_segment *lseg = desc->pg_lseg;
2899	enum pnfs_try_status trypnfs;
2900
2901	trypnfs = pnfs_try_to_write_data(hdr, call_ops, lseg, how);
2902	switch (trypnfs) {
2903	case PNFS_NOT_ATTEMPTED:
2904		pnfs_write_through_mds(desc, hdr);
2905		break;
2906	case PNFS_ATTEMPTED:
2907		break;
2908	case PNFS_TRY_AGAIN:
2909		/* cleanup hdr and prepare to redo pnfs */
2910		if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2911			struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2912			list_splice_init(&hdr->pages, &mirror->pg_list);
2913			mirror->pg_recoalesce = 1;
2914		}
2915		hdr->mds_ops->rpc_release(hdr);
2916	}
2917}
2918
2919static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
2920{
2921	pnfs_put_lseg(hdr->lseg);
2922	nfs_pgio_header_free(hdr);
2923}
2924
2925int
2926pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
2927{
2928	struct nfs_pgio_header *hdr;
2929	int ret;
2930
2931	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
2932	if (!hdr) {
2933		desc->pg_error = -ENOMEM;
2934		return desc->pg_error;
2935	}
2936	nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
2937
2938	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
2939	ret = nfs_generic_pgio(desc, hdr);
2940	if (!ret)
2941		pnfs_do_write(desc, hdr, desc->pg_ioflags);
2942
2943	return ret;
2944}
2945EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
2946
2947int pnfs_read_done_resend_to_mds(struct nfs_pgio_header *hdr)
2948{
2949	struct nfs_pageio_descriptor pgio;
2950
2951	/* Resend all requests through the MDS */
2952	nfs_pageio_init_read(&pgio, hdr->inode, true, hdr->completion_ops);
2953	return nfs_pageio_resend(&pgio, hdr);
2954}
2955EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
2956
2957static void pnfs_ld_handle_read_error(struct nfs_pgio_header *hdr)
2958{
2959	dprintk("pnfs read error = %d\n", hdr->pnfs_error);
2960	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2961	    PNFS_LAYOUTRET_ON_ERROR) {
2962		pnfs_return_layout(hdr->inode);
2963	}
2964	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2965		hdr->task.tk_status = pnfs_read_done_resend_to_mds(hdr);
2966}
2967
2968/*
2969 * Called by non rpc-based layout drivers
2970 */
2971void pnfs_ld_read_done(struct nfs_pgio_header *hdr)
2972{
2973	if (likely(!hdr->pnfs_error))
2974		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
2975	trace_nfs4_pnfs_read(hdr, hdr->pnfs_error);
2976	if (unlikely(hdr->pnfs_error))
2977		pnfs_ld_handle_read_error(hdr);
2978	hdr->mds_ops->rpc_release(hdr);
2979}
2980EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
2981
2982static void
2983pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
2984		struct nfs_pgio_header *hdr)
2985{
2986	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2987
2988	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2989		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
2990		nfs_pageio_reset_read_mds(desc);
2991		mirror->pg_recoalesce = 1;
2992	}
2993	hdr->completion_ops->completion(hdr);
2994}
2995
2996/*
2997 * Call the appropriate parallel I/O subsystem read function.
2998 */
2999static enum pnfs_try_status
3000pnfs_try_to_read_data(struct nfs_pgio_header *hdr,
3001		       const struct rpc_call_ops *call_ops,
3002		       struct pnfs_layout_segment *lseg)
3003{
3004	struct inode *inode = hdr->inode;
3005	struct nfs_server *nfss = NFS_SERVER(inode);
3006	enum pnfs_try_status trypnfs;
3007
3008	hdr->mds_ops = call_ops;
3009
3010	dprintk("%s: Reading ino:%lu %u@%llu\n",
3011		__func__, inode->i_ino, hdr->args.count, hdr->args.offset);
3012
3013	trypnfs = nfss->pnfs_curr_ld->read_pagelist(hdr);
3014	if (trypnfs != PNFS_NOT_ATTEMPTED)
3015		nfs_inc_stats(inode, NFSIOS_PNFS_READ);
3016	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
3017	return trypnfs;
3018}
3019
3020/* Resend all requests through pnfs. */
3021void pnfs_read_resend_pnfs(struct nfs_pgio_header *hdr,
3022			   unsigned int mirror_idx)
3023{
3024	struct nfs_pageio_descriptor pgio;
3025
3026	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
3027		/* Prevent deadlocks with layoutreturn! */
3028		pnfs_put_lseg(hdr->lseg);
3029		hdr->lseg = NULL;
3030
3031		nfs_pageio_init_read(&pgio, hdr->inode, false,
3032					hdr->completion_ops);
3033		pgio.pg_mirror_idx = mirror_idx;
3034		hdr->task.tk_status = nfs_pageio_resend(&pgio, hdr);
3035	}
3036}
3037EXPORT_SYMBOL_GPL(pnfs_read_resend_pnfs);
3038
3039static void
3040pnfs_do_read(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr)
3041{
3042	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
3043	struct pnfs_layout_segment *lseg = desc->pg_lseg;
3044	enum pnfs_try_status trypnfs;
3045
3046	trypnfs = pnfs_try_to_read_data(hdr, call_ops, lseg);
3047	switch (trypnfs) {
3048	case PNFS_NOT_ATTEMPTED:
3049		pnfs_read_through_mds(desc, hdr);
3050		break;
3051	case PNFS_ATTEMPTED:
3052		break;
3053	case PNFS_TRY_AGAIN:
3054		/* cleanup hdr and prepare to redo pnfs */
3055		if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
3056			struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
3057			list_splice_init(&hdr->pages, &mirror->pg_list);
3058			mirror->pg_recoalesce = 1;
3059		}
3060		hdr->mds_ops->rpc_release(hdr);
3061	}
3062}
3063
3064static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
3065{
3066	pnfs_put_lseg(hdr->lseg);
3067	nfs_pgio_header_free(hdr);
3068}
3069
3070int
3071pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
3072{
3073	struct nfs_pgio_header *hdr;
3074	int ret;
3075
3076	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
3077	if (!hdr) {
3078		desc->pg_error = -ENOMEM;
3079		return desc->pg_error;
3080	}
3081	nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
3082	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
3083	ret = nfs_generic_pgio(desc, hdr);
3084	if (!ret)
3085		pnfs_do_read(desc, hdr);
3086	return ret;
3087}
3088EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
3089
3090static void pnfs_clear_layoutcommitting(struct inode *inode)
3091{
3092	unsigned long *bitlock = &NFS_I(inode)->flags;
3093
3094	clear_bit_unlock(NFS_INO_LAYOUTCOMMITTING, bitlock);
3095	smp_mb__after_atomic();
3096	wake_up_bit(bitlock, NFS_INO_LAYOUTCOMMITTING);
3097}
3098
3099/*
3100 * There can be multiple RW segments.
3101 */
3102static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
3103{
3104	struct pnfs_layout_segment *lseg;
3105
3106	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
3107		if (lseg->pls_range.iomode == IOMODE_RW &&
3108		    test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
3109			list_add(&lseg->pls_lc_list, listp);
3110	}
3111}
3112
3113static void pnfs_list_write_lseg_done(struct inode *inode, struct list_head *listp)
3114{
3115	struct pnfs_layout_segment *lseg, *tmp;
3116
3117	/* Matched by references in pnfs_set_layoutcommit */
3118	list_for_each_entry_safe(lseg, tmp, listp, pls_lc_list) {
3119		list_del_init(&lseg->pls_lc_list);
3120		pnfs_put_lseg(lseg);
3121	}
3122
3123	pnfs_clear_layoutcommitting(inode);
3124}
3125
3126void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
3127{
3128	pnfs_layout_io_set_failed(lseg->pls_layout, lseg->pls_range.iomode);
3129}
3130EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
3131
3132void
3133pnfs_set_layoutcommit(struct inode *inode, struct pnfs_layout_segment *lseg,
3134		loff_t end_pos)
3135{
3136	struct nfs_inode *nfsi = NFS_I(inode);
3137	bool mark_as_dirty = false;
3138
3139	spin_lock(&inode->i_lock);
3140	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
3141		nfsi->layout->plh_lwb = end_pos;
3142		mark_as_dirty = true;
3143		dprintk("%s: Set layoutcommit for inode %lu ",
3144			__func__, inode->i_ino);
3145	} else if (end_pos > nfsi->layout->plh_lwb)
3146		nfsi->layout->plh_lwb = end_pos;
3147	if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags)) {
3148		/* references matched in nfs4_layoutcommit_release */
3149		pnfs_get_lseg(lseg);
3150	}
3151	spin_unlock(&inode->i_lock);
3152	dprintk("%s: lseg %p end_pos %llu\n",
3153		__func__, lseg, nfsi->layout->plh_lwb);
3154
3155	/* if pnfs_layoutcommit_inode() runs between inode locks, the next one
3156	 * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */
3157	if (mark_as_dirty)
3158		mark_inode_dirty_sync(inode);
3159}
3160EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
3161
3162void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data)
3163{
3164	struct nfs_server *nfss = NFS_SERVER(data->args.inode);
3165
3166	if (nfss->pnfs_curr_ld->cleanup_layoutcommit)
3167		nfss->pnfs_curr_ld->cleanup_layoutcommit(data);
3168	pnfs_list_write_lseg_done(data->args.inode, &data->lseg_list);
3169}
3170
3171/*
3172 * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
3173 * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
3174 * data to disk to allow the server to recover the data if it crashes.
3175 * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
3176 * is off, and a COMMIT is sent to a data server, or
3177 * if WRITEs to a data server return NFS_DATA_SYNC.
3178 */
3179int
3180pnfs_layoutcommit_inode(struct inode *inode, bool sync)
3181{
3182	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
3183	struct nfs4_layoutcommit_data *data;
3184	struct nfs_inode *nfsi = NFS_I(inode);
3185	loff_t end_pos;
3186	int status;
3187
3188	if (!pnfs_layoutcommit_outstanding(inode))
3189		return 0;
3190
3191	dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
3192
3193	status = -EAGAIN;
3194	if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
3195		if (!sync)
3196			goto out;
3197		status = wait_on_bit_lock_action(&nfsi->flags,
3198				NFS_INO_LAYOUTCOMMITTING,
3199				nfs_wait_bit_killable,
3200				TASK_KILLABLE|TASK_FREEZABLE_UNSAFE);
3201		if (status)
3202			goto out;
3203	}
3204
3205	status = -ENOMEM;
3206	/* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
3207	data = kzalloc(sizeof(*data), nfs_io_gfp_mask());
3208	if (!data)
3209		goto clear_layoutcommitting;
3210
3211	status = 0;
3212	spin_lock(&inode->i_lock);
3213	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
3214		goto out_unlock;
3215
3216	INIT_LIST_HEAD(&data->lseg_list);
3217	pnfs_list_write_lseg(inode, &data->lseg_list);
3218
3219	end_pos = nfsi->layout->plh_lwb;
3220
3221	nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
3222	data->cred = get_cred(nfsi->layout->plh_lc_cred);
3223	spin_unlock(&inode->i_lock);
3224
3225	data->args.inode = inode;
 
3226	nfs_fattr_init(&data->fattr);
3227	data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
3228	data->res.fattr = &data->fattr;
3229	if (end_pos != 0)
3230		data->args.lastbytewritten = end_pos - 1;
3231	else
3232		data->args.lastbytewritten = U64_MAX;
3233	data->res.server = NFS_SERVER(inode);
3234
3235	if (ld->prepare_layoutcommit) {
3236		status = ld->prepare_layoutcommit(&data->args);
3237		if (status) {
3238			put_cred(data->cred);
3239			spin_lock(&inode->i_lock);
3240			set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags);
3241			if (end_pos > nfsi->layout->plh_lwb)
3242				nfsi->layout->plh_lwb = end_pos;
3243			goto out_unlock;
3244		}
3245	}
3246
3247
3248	status = nfs4_proc_layoutcommit(data, sync);
3249out:
3250	if (status)
3251		mark_inode_dirty_sync(inode);
3252	dprintk("<-- %s status %d\n", __func__, status);
3253	return status;
3254out_unlock:
3255	spin_unlock(&inode->i_lock);
3256	kfree(data);
3257clear_layoutcommitting:
3258	pnfs_clear_layoutcommitting(inode);
3259	goto out;
3260}
3261EXPORT_SYMBOL_GPL(pnfs_layoutcommit_inode);
3262
3263int
3264pnfs_generic_sync(struct inode *inode, bool datasync)
3265{
3266	return pnfs_layoutcommit_inode(inode, true);
3267}
3268EXPORT_SYMBOL_GPL(pnfs_generic_sync);
3269
3270struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
3271{
3272	struct nfs4_threshold *thp;
3273
3274	thp = kzalloc(sizeof(*thp), nfs_io_gfp_mask());
3275	if (!thp) {
3276		dprintk("%s mdsthreshold allocation failed\n", __func__);
3277		return NULL;
3278	}
3279	return thp;
3280}
3281
3282#if IS_ENABLED(CONFIG_NFS_V4_2)
3283int
3284pnfs_report_layoutstat(struct inode *inode, gfp_t gfp_flags)
3285{
3286	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
3287	struct nfs_server *server = NFS_SERVER(inode);
3288	struct nfs_inode *nfsi = NFS_I(inode);
3289	struct nfs42_layoutstat_data *data;
3290	struct pnfs_layout_hdr *hdr;
3291	int status = 0;
3292
3293	if (!pnfs_enabled_sb(server) || !ld->prepare_layoutstats)
3294		goto out;
3295
3296	if (!nfs_server_capable(inode, NFS_CAP_LAYOUTSTATS))
3297		goto out;
3298
3299	if (test_and_set_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags))
3300		goto out;
3301
3302	spin_lock(&inode->i_lock);
3303	if (!NFS_I(inode)->layout) {
3304		spin_unlock(&inode->i_lock);
3305		goto out_clear_layoutstats;
3306	}
3307	hdr = NFS_I(inode)->layout;
3308	pnfs_get_layout_hdr(hdr);
3309	spin_unlock(&inode->i_lock);
3310
3311	data = kzalloc(sizeof(*data), gfp_flags);
3312	if (!data) {
3313		status = -ENOMEM;
3314		goto out_put;
3315	}
3316
3317	data->args.fh = NFS_FH(inode);
3318	data->args.inode = inode;
3319	status = ld->prepare_layoutstats(&data->args);
3320	if (status)
3321		goto out_free;
3322
3323	status = nfs42_proc_layoutstats_generic(NFS_SERVER(inode), data);
3324
3325out:
3326	dprintk("%s returns %d\n", __func__, status);
3327	return status;
3328
3329out_free:
3330	kfree(data);
3331out_put:
3332	pnfs_put_layout_hdr(hdr);
3333out_clear_layoutstats:
3334	smp_mb__before_atomic();
3335	clear_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags);
3336	smp_mb__after_atomic();
3337	goto out;
3338}
3339EXPORT_SYMBOL_GPL(pnfs_report_layoutstat);
3340#endif
3341
3342unsigned int layoutstats_timer;
3343module_param(layoutstats_timer, uint, 0644);
3344EXPORT_SYMBOL_GPL(layoutstats_timer);