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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);
v3.5.6
   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 "internal.h"
  34#include "pnfs.h"
  35#include "iostat.h"
 
 
 
  36
  37#define NFSDBG_FACILITY		NFSDBG_PNFS
 
  38
  39/* Locking:
  40 *
  41 * pnfs_spinlock:
  42 *      protects pnfs_modules_tbl.
  43 */
  44static DEFINE_SPINLOCK(pnfs_spinlock);
  45
  46/*
  47 * pnfs_modules_tbl holds all pnfs modules
  48 */
  49static LIST_HEAD(pnfs_modules_tbl);
  50
 
 
 
 
 
 
 
 
  51/* Return the registered pnfs layout driver module matching given id */
  52static struct pnfs_layoutdriver_type *
  53find_pnfs_driver_locked(u32 id)
  54{
  55	struct pnfs_layoutdriver_type *local;
  56
  57	list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid)
  58		if (local->id == id)
  59			goto out;
  60	local = NULL;
  61out:
  62	dprintk("%s: Searching for id %u, found %p\n", __func__, id, local);
  63	return local;
  64}
  65
  66static struct pnfs_layoutdriver_type *
  67find_pnfs_driver(u32 id)
  68{
  69	struct pnfs_layoutdriver_type *local;
  70
  71	spin_lock(&pnfs_spinlock);
  72	local = find_pnfs_driver_locked(id);
  73	if (local != NULL && !try_module_get(local->owner)) {
  74		dprintk("%s: Could not grab reference on module\n", __func__);
  75		local = NULL;
  76	}
  77	spin_unlock(&pnfs_spinlock);
  78	return local;
  79}
  80
  81void
  82unset_pnfs_layoutdriver(struct nfs_server *nfss)
  83{
  84	if (nfss->pnfs_curr_ld) {
  85		if (nfss->pnfs_curr_ld->clear_layoutdriver)
  86			nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
  87		/* Decrement the MDS count. Purge the deviceid cache if zero */
  88		if (atomic_dec_and_test(&nfss->nfs_client->cl_mds_count))
  89			nfs4_deviceid_purge_client(nfss->nfs_client);
  90		module_put(nfss->pnfs_curr_ld->owner);
  91	}
  92	nfss->pnfs_curr_ld = NULL;
  93}
  94
  95/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  96 * Try to set the server's pnfs module to the pnfs layout type specified by id.
  97 * Currently only one pNFS layout driver per filesystem is supported.
  98 *
  99 * @id layout type. Zero (illegal layout type) indicates pNFS not in use.
 100 */
 101void
 102set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
 103		      u32 id)
 104{
 105	struct pnfs_layoutdriver_type *ld_type = NULL;
 
 
 106
 107	if (id == 0)
 108		goto out_no_driver;
 109	if (!(server->nfs_client->cl_exchange_flags &
 110		 (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
 111		printk(KERN_ERR "NFS: %s: id %u cl_exchange_flags 0x%x\n",
 112			__func__, id, server->nfs_client->cl_exchange_flags);
 113		goto out_no_driver;
 114	}
 115	ld_type = find_pnfs_driver(id);
 116	if (!ld_type) {
 117		request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX, id);
 
 
 
 118		ld_type = find_pnfs_driver(id);
 119		if (!ld_type) {
 120			dprintk("%s: No pNFS module found for %u.\n",
 121				__func__, id);
 122			goto out_no_driver;
 123		}
 
 
 
 
 
 
 
 124	}
 
 125	server->pnfs_curr_ld = ld_type;
 126	if (ld_type->set_layoutdriver
 127	    && ld_type->set_layoutdriver(server, mntfh)) {
 128		printk(KERN_ERR "NFS: %s: Error initializing pNFS layout "
 129			"driver %u.\n", __func__, id);
 130		module_put(ld_type->owner);
 131		goto out_no_driver;
 132	}
 133	/* Bump the MDS count */
 134	atomic_inc(&server->nfs_client->cl_mds_count);
 135
 136	dprintk("%s: pNFS module for %u set\n", __func__, id);
 137	return;
 138
 139out_no_driver:
 140	dprintk("%s: Using NFSv4 I/O\n", __func__);
 141	server->pnfs_curr_ld = NULL;
 142}
 143
 144int
 145pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 146{
 147	int status = -EINVAL;
 148	struct pnfs_layoutdriver_type *tmp;
 149
 150	if (ld_type->id == 0) {
 151		printk(KERN_ERR "NFS: %s id 0 is reserved\n", __func__);
 152		return status;
 153	}
 154	if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
 155		printk(KERN_ERR "NFS: %s Layout driver must provide "
 156		       "alloc_lseg and free_lseg.\n", __func__);
 157		return status;
 158	}
 159
 160	spin_lock(&pnfs_spinlock);
 161	tmp = find_pnfs_driver_locked(ld_type->id);
 162	if (!tmp) {
 163		list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
 164		status = 0;
 165		dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
 166			ld_type->name);
 167	} else {
 168		printk(KERN_ERR "NFS: %s Module with id %d already loaded!\n",
 169			__func__, ld_type->id);
 170	}
 171	spin_unlock(&pnfs_spinlock);
 172
 173	return status;
 174}
 175EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);
 176
 177void
 178pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 179{
 180	dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
 181	spin_lock(&pnfs_spinlock);
 182	list_del(&ld_type->pnfs_tblid);
 183	spin_unlock(&pnfs_spinlock);
 184}
 185EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
 186
 187/*
 188 * pNFS client layout cache
 189 */
 190
 191/* Need to hold i_lock if caller does not already hold reference */
 192void
 193get_layout_hdr(struct pnfs_layout_hdr *lo)
 194{
 195	atomic_inc(&lo->plh_refcount);
 196}
 197
 198static struct pnfs_layout_hdr *
 199pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags)
 200{
 201	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
 202	return ld->alloc_layout_hdr ? ld->alloc_layout_hdr(ino, gfp_flags) :
 203		kzalloc(sizeof(struct pnfs_layout_hdr), gfp_flags);
 204}
 205
 206static void
 207pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
 208{
 209	struct pnfs_layoutdriver_type *ld = NFS_SERVER(lo->plh_inode)->pnfs_curr_ld;
 
 
 
 
 
 
 
 
 
 210	put_rpccred(lo->plh_lc_cred);
 211	return ld->alloc_layout_hdr ? ld->free_layout_hdr(lo) : kfree(lo);
 212}
 213
 214static void
 215destroy_layout_hdr(struct pnfs_layout_hdr *lo)
 216{
 
 217	dprintk("%s: freeing layout cache %p\n", __func__, lo);
 218	BUG_ON(!list_empty(&lo->plh_layouts));
 219	NFS_I(lo->plh_inode)->layout = NULL;
 220	pnfs_free_layout_hdr(lo);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 221}
 222
 223static void
 224put_layout_hdr_locked(struct pnfs_layout_hdr *lo)
 
 225{
 226	if (atomic_dec_and_test(&lo->plh_refcount))
 227		destroy_layout_hdr(lo);
 
 
 
 
 228}
 229
 230void
 231put_layout_hdr(struct pnfs_layout_hdr *lo)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 232{
 233	struct inode *inode = lo->plh_inode;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 234
 235	if (atomic_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
 236		destroy_layout_hdr(lo);
 237		spin_unlock(&inode->i_lock);
 
 
 
 
 
 
 
 
 
 
 
 238	}
 
 239}
 240
 241static void
 242init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg)
 
 
 243{
 244	INIT_LIST_HEAD(&lseg->pls_list);
 245	INIT_LIST_HEAD(&lseg->pls_lc_list);
 246	atomic_set(&lseg->pls_refcount, 1);
 247	smp_mb();
 248	set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
 249	lseg->pls_layout = lo;
 
 
 250}
 251
 252static void free_lseg(struct pnfs_layout_segment *lseg)
 253{
 254	struct inode *ino = lseg->pls_layout->plh_inode;
 255
 256	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
 257	/* Matched by get_layout_hdr in pnfs_insert_layout */
 258	put_layout_hdr(NFS_I(ino)->layout);
 259}
 260
 261static void
 262put_lseg_common(struct pnfs_layout_segment *lseg)
 
 263{
 264	struct inode *inode = lseg->pls_layout->plh_inode;
 265
 266	WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 267	list_del_init(&lseg->pls_list);
 268	if (list_empty(&lseg->pls_layout->plh_segs)) {
 269		set_bit(NFS_LAYOUT_DESTROYED, &lseg->pls_layout->plh_flags);
 270		/* Matched by initial refcount set in alloc_init_layout_hdr */
 271		put_layout_hdr_locked(lseg->pls_layout);
 
 
 
 
 
 
 272	}
 273	rpc_wake_up(&NFS_SERVER(inode)->roc_rpcwaitq);
 
 
 
 
 
 
 
 
 
 
 
 
 274}
 275
 276void
 277put_lseg(struct pnfs_layout_segment *lseg)
 278{
 
 279	struct inode *inode;
 280
 281	if (!lseg)
 282		return;
 283
 284	dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
 285		atomic_read(&lseg->pls_refcount),
 286		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 287	inode = lseg->pls_layout->plh_inode;
 288	if (atomic_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
 289		LIST_HEAD(free_me);
 290
 291		put_lseg_common(lseg);
 292		list_add(&lseg->pls_list, &free_me);
 
 
 
 
 
 
 
 
 
 
 293		spin_unlock(&inode->i_lock);
 294		pnfs_free_lseg_list(&free_me);
 
 295	}
 296}
 297EXPORT_SYMBOL_GPL(put_lseg);
 298
 299static inline u64
 300end_offset(u64 start, u64 len)
 301{
 302	u64 end;
 303
 304	end = start + len;
 305	return end >= start ? end : NFS4_MAX_UINT64;
 306}
 307
 308/* last octet in a range */
 309static inline u64
 310last_byte_offset(u64 start, u64 len)
 311{
 312	u64 end;
 313
 314	BUG_ON(!len);
 315	end = start + len;
 316	return end > start ? end - 1 : NFS4_MAX_UINT64;
 317}
 318
 319/*
 320 * is l2 fully contained in l1?
 321 *   start1                             end1
 322 *   [----------------------------------)
 323 *           start2           end2
 324 *           [----------------)
 325 */
 326static inline int
 327lo_seg_contained(struct pnfs_layout_range *l1,
 328		 struct pnfs_layout_range *l2)
 329{
 330	u64 start1 = l1->offset;
 331	u64 end1 = end_offset(start1, l1->length);
 332	u64 start2 = l2->offset;
 333	u64 end2 = end_offset(start2, l2->length);
 334
 335	return (start1 <= start2) && (end1 >= end2);
 336}
 337
 338/*
 339 * is l1 and l2 intersecting?
 340 *   start1                             end1
 341 *   [----------------------------------)
 342 *                              start2           end2
 343 *                              [----------------)
 344 */
 345static inline int
 346lo_seg_intersecting(struct pnfs_layout_range *l1,
 347		    struct pnfs_layout_range *l2)
 348{
 349	u64 start1 = l1->offset;
 350	u64 end1 = end_offset(start1, l1->length);
 351	u64 start2 = l2->offset;
 352	u64 end2 = end_offset(start2, l2->length);
 353
 354	return (end1 == NFS4_MAX_UINT64 || end1 > start2) &&
 355	       (end2 == NFS4_MAX_UINT64 || end2 > start1);
 356}
 357
 358static bool
 359should_free_lseg(struct pnfs_layout_range *lseg_range,
 360		 struct pnfs_layout_range *recall_range)
 361{
 362	return (recall_range->iomode == IOMODE_ANY ||
 363		lseg_range->iomode == recall_range->iomode) &&
 364	       lo_seg_intersecting(lseg_range, recall_range);
 365}
 366
 367/* Returns 1 if lseg is removed from list, 0 otherwise */
 368static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
 369			     struct list_head *tmp_list)
 370{
 371	int rv = 0;
 372
 373	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 374		/* Remove the reference keeping the lseg in the
 375		 * list.  It will now be removed when all
 376		 * outstanding io is finished.
 377		 */
 378		dprintk("%s: lseg %p ref %d\n", __func__, lseg,
 379			atomic_read(&lseg->pls_refcount));
 380		if (atomic_dec_and_test(&lseg->pls_refcount)) {
 381			put_lseg_common(lseg);
 382			list_add(&lseg->pls_list, tmp_list);
 383			rv = 1;
 384		}
 385	}
 386	return rv;
 387}
 388
 389/* Returns count of number of matching invalid lsegs remaining in list
 390 * after call.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 391 */
 392int
 393mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 394			    struct list_head *tmp_list,
 395			    struct pnfs_layout_range *recall_range)
 
 396{
 397	struct pnfs_layout_segment *lseg, *next;
 398	int invalid = 0, removed = 0;
 399
 400	dprintk("%s:Begin lo %p\n", __func__, lo);
 401
 402	if (list_empty(&lo->plh_segs)) {
 403		/* Reset MDS Threshold I/O counters */
 404		NFS_I(lo->plh_inode)->write_io = 0;
 405		NFS_I(lo->plh_inode)->read_io = 0;
 406		if (!test_and_set_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags))
 407			put_layout_hdr_locked(lo);
 408		return 0;
 409	}
 410	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 411		if (!recall_range ||
 412		    should_free_lseg(&lseg->pls_range, recall_range)) {
 413			dprintk("%s: freeing lseg %p iomode %d "
 414				"offset %llu length %llu\n", __func__,
 415				lseg, lseg->pls_range.iomode, lseg->pls_range.offset,
 416				lseg->pls_range.length);
 417			invalid++;
 418			removed += mark_lseg_invalid(lseg, tmp_list);
 419		}
 420	dprintk("%s:Return %i\n", __func__, invalid - removed);
 421	return invalid - removed;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 422}
 423
 424/* note free_me must contain lsegs from a single layout_hdr */
 425void
 426pnfs_free_lseg_list(struct list_head *free_me)
 427{
 428	struct pnfs_layout_segment *lseg, *tmp;
 429	struct pnfs_layout_hdr *lo;
 430
 431	if (list_empty(free_me))
 432		return;
 433
 434	lo = list_first_entry(free_me, struct pnfs_layout_segment,
 435			      pls_list)->pls_layout;
 436
 437	if (test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags)) {
 438		struct nfs_client *clp;
 439
 440		clp = NFS_SERVER(lo->plh_inode)->nfs_client;
 441		spin_lock(&clp->cl_lock);
 442		list_del_init(&lo->plh_layouts);
 443		spin_unlock(&clp->cl_lock);
 444	}
 445	list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
 446		list_del(&lseg->pls_list);
 447		free_lseg(lseg);
 448	}
 449}
 450
 451void
 452pnfs_destroy_layout(struct nfs_inode *nfsi)
 453{
 454	struct pnfs_layout_hdr *lo;
 455	LIST_HEAD(tmp_list);
 456
 457	spin_lock(&nfsi->vfs_inode.i_lock);
 458	lo = nfsi->layout;
 459	if (lo) {
 460		lo->plh_block_lgets++; /* permanently block new LAYOUTGETs */
 461		mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 462	}
 463	spin_unlock(&nfsi->vfs_inode.i_lock);
 464	pnfs_free_lseg_list(&tmp_list);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 465}
 466EXPORT_SYMBOL_GPL(pnfs_destroy_layout);
 467
 468/*
 469 * Called by the state manger to remove all layouts established under an
 470 * expired lease.
 471 */
 472void
 473pnfs_destroy_all_layouts(struct nfs_client *clp)
 474{
 475	struct nfs_server *server;
 476	struct pnfs_layout_hdr *lo;
 477	LIST_HEAD(tmp_list);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 478
 479	nfs4_deviceid_mark_client_invalid(clp);
 480	nfs4_deviceid_purge_client(clp);
 
 
 
 
 
 481
 482	spin_lock(&clp->cl_lock);
 483	rcu_read_lock();
 
 484	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 485		if (!list_empty(&server->layouts))
 486			list_splice_init(&server->layouts, &tmp_list);
 
 
 
 
 487	}
 488	rcu_read_unlock();
 489	spin_unlock(&clp->cl_lock);
 490
 491	while (!list_empty(&tmp_list)) {
 492		lo = list_entry(tmp_list.next, struct pnfs_layout_hdr,
 493				plh_layouts);
 494		dprintk("%s freeing layout for inode %lu\n", __func__,
 495			lo->plh_inode->i_ino);
 496		list_del_init(&lo->plh_layouts);
 497		pnfs_destroy_layout(NFS_I(lo->plh_inode));
 
 
 
 
 
 
 
 
 
 
 
 
 
 498	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 499}
 500
 501/* update lo->plh_stateid with new if is more recent */
 502void
 503pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
 504			bool update_barrier)
 505{
 506	u32 oldseq, newseq;
 507
 508	oldseq = be32_to_cpu(lo->plh_stateid.seqid);
 509	newseq = be32_to_cpu(new->seqid);
 510	if ((int)(newseq - oldseq) > 0) {
 
 
 
 
 
 
 
 
 511		nfs4_stateid_copy(&lo->plh_stateid, new);
 512		if (update_barrier) {
 513			u32 new_barrier = be32_to_cpu(new->seqid);
 514
 515			if ((int)(new_barrier - lo->plh_barrier))
 516				lo->plh_barrier = new_barrier;
 517		} else {
 518			/* Because of wraparound, we want to keep the barrier
 519			 * "close" to the current seqids.  It needs to be
 520			 * within 2**31 to count as "behind", so if it
 521			 * gets too near that limit, give us a litle leeway
 522			 * and bring it to within 2**30.
 523			 * NOTE - and yes, this is all unsigned arithmetic.
 524			 */
 525			if (unlikely((newseq - lo->plh_barrier) > (3 << 29)))
 526				lo->plh_barrier = newseq - (1 << 30);
 527		}
 528	}
 
 
 
 
 
 
 529}
 530
 531/* lget is set to 1 if called from inside send_layoutget call chain */
 532static bool
 533pnfs_layoutgets_blocked(struct pnfs_layout_hdr *lo, nfs4_stateid *stateid,
 534			int lget)
 535{
 536	if ((stateid) &&
 537	    (int)(lo->plh_barrier - be32_to_cpu(stateid->seqid)) >= 0)
 538		return true;
 539	return lo->plh_block_lgets ||
 540		test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags) ||
 541		test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
 542		(list_empty(&lo->plh_segs) &&
 543		 (atomic_read(&lo->plh_outstanding) > lget));
 544}
 545
 546int
 547pnfs_choose_layoutget_stateid(nfs4_stateid *dst, struct pnfs_layout_hdr *lo,
 548			      struct nfs4_state *open_state)
 549{
 550	int status = 0;
 551
 552	dprintk("--> %s\n", __func__);
 553	spin_lock(&lo->plh_inode->i_lock);
 554	if (pnfs_layoutgets_blocked(lo, NULL, 1)) {
 555		status = -EAGAIN;
 556	} else if (list_empty(&lo->plh_segs)) {
 557		int seq;
 558
 559		do {
 560			seq = read_seqbegin(&open_state->seqlock);
 561			nfs4_stateid_copy(dst, &open_state->stateid);
 562		} while (read_seqretry(&open_state->seqlock, seq));
 563	} else
 564		nfs4_stateid_copy(dst, &lo->plh_stateid);
 565	spin_unlock(&lo->plh_inode->i_lock);
 566	dprintk("<-- %s\n", __func__);
 567	return status;
 568}
 569
 570/*
 571* Get layout from server.
 572*    for now, assume that whole file layouts are requested.
 573*    arg->offset: 0
 574*    arg->length: all ones
 575*/
 576static struct pnfs_layout_segment *
 577send_layoutget(struct pnfs_layout_hdr *lo,
 578	   struct nfs_open_context *ctx,
 579	   struct pnfs_layout_range *range,
 580	   gfp_t gfp_flags)
 
 581{
 582	struct inode *ino = lo->plh_inode;
 583	struct nfs_server *server = NFS_SERVER(ino);
 584	struct nfs4_layoutget *lgp;
 585	struct pnfs_layout_segment *lseg = NULL;
 586
 587	dprintk("--> %s\n", __func__);
 588
 589	BUG_ON(ctx == NULL);
 
 
 
 
 590	lgp = kzalloc(sizeof(*lgp), gfp_flags);
 591	if (lgp == NULL)
 592		return NULL;
 
 
 593
 594	lgp->args.minlength = PAGE_CACHE_SIZE;
 595	if (lgp->args.minlength > range->length)
 596		lgp->args.minlength = range->length;
 
 
 
 
 
 
 597	lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
 598	lgp->args.range = *range;
 599	lgp->args.type = server->pnfs_curr_ld->id;
 600	lgp->args.inode = ino;
 601	lgp->args.ctx = get_nfs_open_context(ctx);
 602	lgp->lsegpp = &lseg;
 603	lgp->gfp_flags = gfp_flags;
 
 604
 605	/* Synchronously retrieve layout information from server and
 606	 * store in lseg.
 607	 */
 608	nfs4_proc_layoutget(lgp, gfp_flags);
 609	if (!lseg) {
 610		/* remember that LAYOUTGET failed and suspend trying */
 611		set_bit(lo_fail_bit(range->iomode), &lo->plh_flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 612	}
 613
 614	return lseg;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 615}
 616
 617/* Initiates a LAYOUTRETURN(FILE) */
 
 
 
 
 
 
 
 618int
 619_pnfs_return_layout(struct inode *ino)
 620{
 621	struct pnfs_layout_hdr *lo = NULL;
 622	struct nfs_inode *nfsi = NFS_I(ino);
 623	LIST_HEAD(tmp_list);
 624	struct nfs4_layoutreturn *lrp;
 625	nfs4_stateid stateid;
 626	int status = 0;
 
 627
 628	dprintk("--> %s\n", __func__);
 629
 630	spin_lock(&ino->i_lock);
 631	lo = nfsi->layout;
 632	if (!lo) {
 633		spin_unlock(&ino->i_lock);
 634		dprintk("%s: no layout to return\n", __func__);
 635		return status;
 636	}
 637	stateid = nfsi->layout->plh_stateid;
 638	/* Reference matched in nfs4_layoutreturn_release */
 639	get_layout_hdr(lo);
 640	mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
 641	lo->plh_block_lgets++;
 642	spin_unlock(&ino->i_lock);
 643	pnfs_free_lseg_list(&tmp_list);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 644
 645	WARN_ON(test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags));
 646
 647	lrp = kzalloc(sizeof(*lrp), GFP_KERNEL);
 648	if (unlikely(lrp == NULL)) {
 649		status = -ENOMEM;
 650		set_bit(NFS_LAYOUT_RW_FAILED, &lo->plh_flags);
 651		set_bit(NFS_LAYOUT_RO_FAILED, &lo->plh_flags);
 652		put_layout_hdr(lo);
 653		goto out;
 654	}
 655
 656	lrp->args.stateid = stateid;
 657	lrp->args.layout_type = NFS_SERVER(ino)->pnfs_curr_ld->id;
 658	lrp->args.inode = ino;
 659	lrp->args.layout = lo;
 660	lrp->clp = NFS_SERVER(ino)->nfs_client;
 661
 662	status = nfs4_proc_layoutreturn(lrp);
 663out:
 664	dprintk("<-- %s status: %d\n", __func__, status);
 665	return status;
 666}
 667EXPORT_SYMBOL_GPL(_pnfs_return_layout);
 668
 669bool pnfs_roc(struct inode *ino)
 
 670{
 671	struct pnfs_layout_hdr *lo;
 672	struct pnfs_layout_segment *lseg, *tmp;
 673	LIST_HEAD(tmp_list);
 674	bool found = false;
 675
 676	spin_lock(&ino->i_lock);
 677	lo = NFS_I(ino)->layout;
 678	if (!lo || !test_and_clear_bit(NFS_LAYOUT_ROC, &lo->plh_flags) ||
 679	    test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags))
 680		goto out_nolayout;
 681	list_for_each_entry_safe(lseg, tmp, &lo->plh_segs, pls_list)
 682		if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
 683			mark_lseg_invalid(lseg, &tmp_list);
 684			found = true;
 685		}
 686	if (!found)
 687		goto out_nolayout;
 688	lo->plh_block_lgets++;
 689	get_layout_hdr(lo); /* matched in pnfs_roc_release */
 690	spin_unlock(&ino->i_lock);
 691	pnfs_free_lseg_list(&tmp_list);
 692	return true;
 693
 694out_nolayout:
 695	spin_unlock(&ino->i_lock);
 696	return false;
 
 
 697}
 698
 699void pnfs_roc_release(struct inode *ino)
 
 
 
 700{
 
 
 
 701	struct pnfs_layout_hdr *lo;
 
 
 
 
 
 702
 
 
 
 703	spin_lock(&ino->i_lock);
 704	lo = NFS_I(ino)->layout;
 705	lo->plh_block_lgets--;
 706	put_layout_hdr_locked(lo);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 707	spin_unlock(&ino->i_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 708}
 709
 710void pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
 711{
 712	struct pnfs_layout_hdr *lo;
 713
 714	spin_lock(&ino->i_lock);
 715	lo = NFS_I(ino)->layout;
 716	if ((int)(barrier - lo->plh_barrier) > 0)
 717		lo->plh_barrier = barrier;
 718	spin_unlock(&ino->i_lock);
 
 
 
 
 
 
 
 
 
 
 
 719}
 720
 721bool pnfs_roc_drain(struct inode *ino, u32 *barrier)
 722{
 723	struct nfs_inode *nfsi = NFS_I(ino);
 724	struct pnfs_layout_segment *lseg;
 725	bool found = false;
 726
 727	spin_lock(&ino->i_lock);
 728	list_for_each_entry(lseg, &nfsi->layout->plh_segs, pls_list)
 729		if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
 730			found = true;
 731			break;
 732		}
 733	if (!found) {
 734		struct pnfs_layout_hdr *lo = nfsi->layout;
 735		u32 current_seqid = be32_to_cpu(lo->plh_stateid.seqid);
 736
 737		/* Since close does not return a layout stateid for use as
 738		 * a barrier, we choose the worst-case barrier.
 739		 */
 740		*barrier = current_seqid + atomic_read(&lo->plh_outstanding);
 
 
 
 741	}
 742	spin_unlock(&ino->i_lock);
 743	return found;
 744}
 745
 746/*
 747 * Compare two layout segments for sorting into layout cache.
 748 * We want to preferentially return RW over RO layouts, so ensure those
 749 * are seen first.
 750 */
 751static s64
 752cmp_layout(struct pnfs_layout_range *l1,
 753	   struct pnfs_layout_range *l2)
 754{
 755	s64 d;
 756
 757	/* high offset > low offset */
 758	d = l1->offset - l2->offset;
 759	if (d)
 760		return d;
 761
 762	/* short length > long length */
 763	d = l2->length - l1->length;
 764	if (d)
 765		return d;
 766
 767	/* read > read/write */
 768	return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
 769}
 770
 771static void
 772pnfs_insert_layout(struct pnfs_layout_hdr *lo,
 773		   struct pnfs_layout_segment *lseg)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 774{
 775	struct pnfs_layout_segment *lp;
 776
 777	dprintk("%s:Begin\n", __func__);
 778
 779	assert_spin_locked(&lo->plh_inode->i_lock);
 780	list_for_each_entry(lp, &lo->plh_segs, pls_list) {
 781		if (cmp_layout(&lseg->pls_range, &lp->pls_range) > 0)
 
 
 
 
 
 782			continue;
 783		list_add_tail(&lseg->pls_list, &lp->pls_list);
 784		dprintk("%s: inserted lseg %p "
 785			"iomode %d offset %llu length %llu before "
 786			"lp %p iomode %d offset %llu length %llu\n",
 787			__func__, lseg, lseg->pls_range.iomode,
 788			lseg->pls_range.offset, lseg->pls_range.length,
 789			lp, lp->pls_range.iomode, lp->pls_range.offset,
 790			lp->pls_range.length);
 791		goto out;
 792	}
 793	list_add_tail(&lseg->pls_list, &lo->plh_segs);
 794	dprintk("%s: inserted lseg %p "
 795		"iomode %d offset %llu length %llu at tail\n",
 796		__func__, lseg, lseg->pls_range.iomode,
 797		lseg->pls_range.offset, lseg->pls_range.length);
 798out:
 799	get_layout_hdr(lo);
 800
 801	dprintk("%s:Return\n", __func__);
 802}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 803
 804static struct pnfs_layout_hdr *
 805alloc_init_layout_hdr(struct inode *ino,
 806		      struct nfs_open_context *ctx,
 807		      gfp_t gfp_flags)
 808{
 809	struct pnfs_layout_hdr *lo;
 810
 811	lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
 812	if (!lo)
 813		return NULL;
 814	atomic_set(&lo->plh_refcount, 1);
 815	INIT_LIST_HEAD(&lo->plh_layouts);
 816	INIT_LIST_HEAD(&lo->plh_segs);
 817	INIT_LIST_HEAD(&lo->plh_bulk_recall);
 
 818	lo->plh_inode = ino;
 819	lo->plh_lc_cred = get_rpccred(ctx->state->owner->so_cred);
 
 820	return lo;
 821}
 822
 823static struct pnfs_layout_hdr *
 824pnfs_find_alloc_layout(struct inode *ino,
 825		       struct nfs_open_context *ctx,
 826		       gfp_t gfp_flags)
 
 
 827{
 828	struct nfs_inode *nfsi = NFS_I(ino);
 829	struct pnfs_layout_hdr *new = NULL;
 830
 831	dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
 832
 833	assert_spin_locked(&ino->i_lock);
 834	if (nfsi->layout) {
 835		if (test_bit(NFS_LAYOUT_DESTROYED, &nfsi->layout->plh_flags))
 836			return NULL;
 837		else
 838			return nfsi->layout;
 839	}
 840	spin_unlock(&ino->i_lock);
 841	new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
 842	spin_lock(&ino->i_lock);
 843
 844	if (likely(nfsi->layout == NULL))	/* Won the race? */
 845		nfsi->layout = new;
 846	else
 
 847		pnfs_free_layout_hdr(new);
 
 
 848	return nfsi->layout;
 849}
 850
 851/*
 852 * iomode matching rules:
 853 * iomode	lseg	match
 854 * -----	-----	-----
 855 * ANY		READ	true
 856 * ANY		RW	true
 857 * RW		READ	false
 858 * RW		RW	true
 859 * READ		READ	true
 860 * READ		RW	true
 
 
 861 */
 862static int
 863is_matching_lseg(struct pnfs_layout_range *ls_range,
 864		 struct pnfs_layout_range *range)
 
 865{
 866	struct pnfs_layout_range range1;
 867
 868	if ((range->iomode == IOMODE_RW &&
 869	     ls_range->iomode != IOMODE_RW) ||
 870	    !lo_seg_intersecting(ls_range, range))
 
 
 871		return 0;
 872
 873	/* range1 covers only the first byte in the range */
 874	range1 = *range;
 875	range1.length = 1;
 876	return lo_seg_contained(ls_range, &range1);
 877}
 878
 879/*
 880 * lookup range in layout
 881 */
 882static struct pnfs_layout_segment *
 883pnfs_find_lseg(struct pnfs_layout_hdr *lo,
 884		struct pnfs_layout_range *range)
 
 885{
 886	struct pnfs_layout_segment *lseg, *ret = NULL;
 887
 888	dprintk("%s:Begin\n", __func__);
 889
 890	assert_spin_locked(&lo->plh_inode->i_lock);
 891	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
 892		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
 893		    is_matching_lseg(&lseg->pls_range, range)) {
 894			ret = get_lseg(lseg);
 
 
 895			break;
 896		}
 897		if (lseg->pls_range.offset > range->offset)
 898			break;
 899	}
 900
 901	dprintk("%s:Return lseg %p ref %d\n",
 902		__func__, ret, ret ? atomic_read(&ret->pls_refcount) : 0);
 903	return ret;
 904}
 905
 906/*
 907 * Use mdsthreshold hints set at each OPEN to determine if I/O should go
 908 * to the MDS or over pNFS
 909 *
 910 * The nfs_inode read_io and write_io fields are cumulative counters reset
 911 * when there are no layout segments. Note that in pnfs_update_layout iomode
 912 * is set to IOMODE_READ for a READ request, and set to IOMODE_RW for a
 913 * WRITE request.
 914 *
 915 * A return of true means use MDS I/O.
 916 *
 917 * From rfc 5661:
 918 * If a file's size is smaller than the file size threshold, data accesses
 919 * SHOULD be sent to the metadata server.  If an I/O request has a length that
 920 * is below the I/O size threshold, the I/O SHOULD be sent to the metadata
 921 * server.  If both file size and I/O size are provided, the client SHOULD
 922 * reach or exceed  both thresholds before sending its read or write
 923 * requests to the data server.
 924 */
 925static bool pnfs_within_mdsthreshold(struct nfs_open_context *ctx,
 926				     struct inode *ino, int iomode)
 927{
 928	struct nfs4_threshold *t = ctx->mdsthreshold;
 929	struct nfs_inode *nfsi = NFS_I(ino);
 930	loff_t fsize = i_size_read(ino);
 931	bool size = false, size_set = false, io = false, io_set = false, ret = false;
 932
 933	if (t == NULL)
 934		return ret;
 935
 936	dprintk("%s bm=0x%x rd_sz=%llu wr_sz=%llu rd_io=%llu wr_io=%llu\n",
 937		__func__, t->bm, t->rd_sz, t->wr_sz, t->rd_io_sz, t->wr_io_sz);
 938
 939	switch (iomode) {
 940	case IOMODE_READ:
 941		if (t->bm & THRESHOLD_RD) {
 942			dprintk("%s fsize %llu\n", __func__, fsize);
 943			size_set = true;
 944			if (fsize < t->rd_sz)
 945				size = true;
 946		}
 947		if (t->bm & THRESHOLD_RD_IO) {
 948			dprintk("%s nfsi->read_io %llu\n", __func__,
 949				nfsi->read_io);
 950			io_set = true;
 951			if (nfsi->read_io < t->rd_io_sz)
 952				io = true;
 953		}
 954		break;
 955	case IOMODE_RW:
 956		if (t->bm & THRESHOLD_WR) {
 957			dprintk("%s fsize %llu\n", __func__, fsize);
 958			size_set = true;
 959			if (fsize < t->wr_sz)
 960				size = true;
 961		}
 962		if (t->bm & THRESHOLD_WR_IO) {
 963			dprintk("%s nfsi->write_io %llu\n", __func__,
 964				nfsi->write_io);
 965			io_set = true;
 966			if (nfsi->write_io < t->wr_io_sz)
 967				io = true;
 968		}
 969		break;
 970	}
 971	if (size_set && io_set) {
 972		if (size && io)
 973			ret = true;
 974	} else if (size || io)
 975		ret = true;
 976
 977	dprintk("<-- %s size %d io %d ret %d\n", __func__, size, io, ret);
 978	return ret;
 979}
 980
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 981/*
 982 * Layout segment is retreived from the server if not cached.
 983 * The appropriate layout segment is referenced and returned to the caller.
 984 */
 985struct pnfs_layout_segment *
 986pnfs_update_layout(struct inode *ino,
 987		   struct nfs_open_context *ctx,
 988		   loff_t pos,
 989		   u64 count,
 990		   enum pnfs_iomode iomode,
 
 991		   gfp_t gfp_flags)
 992{
 993	struct pnfs_layout_range arg = {
 994		.iomode = iomode,
 995		.offset = pos,
 996		.length = count,
 997	};
 998	unsigned pg_offset;
 999	struct nfs_inode *nfsi = NFS_I(ino);
1000	struct nfs_server *server = NFS_SERVER(ino);
1001	struct nfs_client *clp = server->nfs_client;
1002	struct pnfs_layout_hdr *lo;
1003	struct pnfs_layout_segment *lseg = NULL;
1004	bool first = false;
 
 
 
 
 
 
 
 
 
1005
1006	if (!pnfs_enabled_sb(NFS_SERVER(ino)))
1007		return NULL;
 
 
 
1008
1009	if (pnfs_within_mdsthreshold(ctx, ino, iomode))
1010		return NULL;
 
 
 
1011
 
 
 
1012	spin_lock(&ino->i_lock);
1013	lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
1014	if (lo == NULL) {
1015		dprintk("%s ERROR: can't get pnfs_layout_hdr\n", __func__);
1016		goto out_unlock;
 
 
1017	}
1018
1019	/* Do we even need to bother with this? */
1020	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
 
 
1021		dprintk("%s matches recall, use MDS\n", __func__);
1022		goto out_unlock;
1023	}
1024
1025	/* if LAYOUTGET already failed once we don't try again */
1026	if (test_bit(lo_fail_bit(iomode), &nfsi->layout->plh_flags))
 
 
1027		goto out_unlock;
 
1028
1029	/* Check to see if the layout for the given range already exists */
1030	lseg = pnfs_find_lseg(lo, &arg);
1031	if (lseg)
 
1032		goto out_unlock;
 
1033
1034	if (pnfs_layoutgets_blocked(lo, NULL, 0))
 
 
1035		goto out_unlock;
1036	atomic_inc(&lo->plh_outstanding);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1037
1038	get_layout_hdr(lo);
1039	if (list_empty(&lo->plh_segs))
1040		first = true;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1041	spin_unlock(&ino->i_lock);
1042	if (first) {
 
1043		/* The lo must be on the clp list if there is any
1044		 * chance of a CB_LAYOUTRECALL(FILE) coming in.
1045		 */
1046		spin_lock(&clp->cl_lock);
1047		BUG_ON(!list_empty(&lo->plh_layouts));
1048		list_add_tail(&lo->plh_layouts, &server->layouts);
1049		spin_unlock(&clp->cl_lock);
1050	}
1051
1052	pg_offset = arg.offset & ~PAGE_CACHE_MASK;
1053	if (pg_offset) {
1054		arg.offset -= pg_offset;
1055		arg.length += pg_offset;
1056	}
1057	if (arg.length != NFS4_MAX_UINT64)
1058		arg.length = PAGE_CACHE_ALIGN(arg.length);
1059
1060	lseg = send_layoutget(lo, ctx, &arg, gfp_flags);
1061	if (!lseg && first) {
1062		spin_lock(&clp->cl_lock);
1063		list_del_init(&lo->plh_layouts);
1064		spin_unlock(&clp->cl_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1065	}
1066	atomic_dec(&lo->plh_outstanding);
1067	put_layout_hdr(lo);
 
 
 
1068out:
1069	dprintk("%s end, state 0x%lx lseg %p\n", __func__,
1070		nfsi->layout ? nfsi->layout->plh_flags : -1, lseg);
 
 
 
 
 
 
1071	return lseg;
1072out_unlock:
1073	spin_unlock(&ino->i_lock);
1074	goto out;
1075}
1076EXPORT_SYMBOL_GPL(pnfs_update_layout);
1077
1078int
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1079pnfs_layout_process(struct nfs4_layoutget *lgp)
1080{
1081	struct pnfs_layout_hdr *lo = NFS_I(lgp->args.inode)->layout;
1082	struct nfs4_layoutget_res *res = &lgp->res;
1083	struct pnfs_layout_segment *lseg;
1084	struct inode *ino = lo->plh_inode;
1085	int status = 0;
 
 
 
1086
1087	/* Inject layout blob into I/O device driver */
1088	lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
1089	if (!lseg || IS_ERR(lseg)) {
1090		if (!lseg)
1091			status = -ENOMEM;
1092		else
1093			status = PTR_ERR(lseg);
1094		dprintk("%s: Could not allocate layout: error %d\n",
1095		       __func__, status);
1096		goto out;
1097	}
1098
 
 
1099	spin_lock(&ino->i_lock);
1100	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1101		dprintk("%s forget reply due to recall\n", __func__);
1102		goto out_forget_reply;
1103	}
1104
1105	if (pnfs_layoutgets_blocked(lo, &res->stateid, 1)) {
1106		dprintk("%s forget reply due to state\n", __func__);
1107		goto out_forget_reply;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1108	}
1109	init_lseg(lo, lseg);
1110	lseg->pls_range = res->range;
1111	*lgp->lsegpp = get_lseg(lseg);
1112	pnfs_insert_layout(lo, lseg);
1113
1114	if (res->return_on_close) {
 
 
 
 
1115		set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
1116		set_bit(NFS_LAYOUT_ROC, &lo->plh_flags);
1117	}
1118
1119	/* Done processing layoutget. Set the layout stateid */
1120	pnfs_set_layout_stateid(lo, &res->stateid, false);
1121	spin_unlock(&ino->i_lock);
1122out:
1123	return status;
1124
1125out_forget_reply:
1126	spin_unlock(&ino->i_lock);
1127	lseg->pls_layout = lo;
1128	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
1129	goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1130}
1131
1132void
1133pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
1134{
1135	BUG_ON(pgio->pg_lseg != NULL);
 
 
 
 
 
 
 
 
1136
1137	if (req->wb_offset != req->wb_pgbase) {
1138		nfs_pageio_reset_read_mds(pgio);
1139		return;
 
 
 
 
 
 
 
 
 
1140	}
1141	pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
1142					   req->wb_context,
1143					   req_offset(req),
1144					   req->wb_bytes,
1145					   IOMODE_READ,
1146					   GFP_KERNEL);
1147	/* If no lseg, fall back to read through mds */
1148	if (pgio->pg_lseg == NULL)
1149		nfs_pageio_reset_read_mds(pgio);
1150
1151}
1152EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);
1153
1154void
1155pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
 
1156{
1157	BUG_ON(pgio->pg_lseg != NULL);
1158
1159	if (req->wb_offset != req->wb_pgbase) {
1160		nfs_pageio_reset_write_mds(pgio);
1161		return;
 
 
 
 
 
 
 
 
 
 
1162	}
1163	pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
1164					   req->wb_context,
1165					   req_offset(req),
1166					   req->wb_bytes,
1167					   IOMODE_RW,
1168					   GFP_NOFS);
1169	/* If no lseg, fall back to write through mds */
1170	if (pgio->pg_lseg == NULL)
1171		nfs_pageio_reset_write_mds(pgio);
1172}
1173EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
1174
1175bool
1176pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode,
1177		      const struct nfs_pgio_completion_ops *compl_ops)
1178{
1179	struct nfs_server *server = NFS_SERVER(inode);
1180	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
1181
1182	if (ld == NULL)
1183		return false;
1184	nfs_pageio_init(pgio, inode, ld->pg_read_ops, compl_ops,
1185			server->rsize, 0);
1186	return true;
1187}
 
1188
1189bool
1190pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode,
1191		       int ioflags,
1192		       const struct nfs_pgio_completion_ops *compl_ops)
 
 
 
1193{
1194	struct nfs_server *server = NFS_SERVER(inode);
1195	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
1196
1197	if (ld == NULL)
1198		return false;
1199	nfs_pageio_init(pgio, inode, ld->pg_write_ops, compl_ops,
1200			server->wsize, ioflags);
1201	return true;
1202}
1203
1204bool
1205pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
1206		     struct nfs_page *req)
1207{
1208	if (pgio->pg_lseg == NULL)
1209		return nfs_generic_pg_test(pgio, prev, req);
1210
1211	/*
1212	 * Test if a nfs_page is fully contained in the pnfs_layout_range.
1213	 * Note that this test makes several assumptions:
1214	 * - that the previous nfs_page in the struct nfs_pageio_descriptor
1215	 *   is known to lie within the range.
1216	 *   - that the nfs_page being tested is known to be contiguous with the
1217	 *   previous nfs_page.
1218	 *   - Layout ranges are page aligned, so we only have to test the
1219	 *   start offset of the request.
1220	 *
1221	 * Please also note that 'end_offset' is actually the offset of the
1222	 * first byte that lies outside the pnfs_layout_range. FIXME?
1223	 *
1224	 */
1225	return req_offset(req) < end_offset(pgio->pg_lseg->pls_range.offset,
1226					 pgio->pg_lseg->pls_range.length);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1227}
1228EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
1229
1230int pnfs_write_done_resend_to_mds(struct inode *inode,
1231				struct list_head *head,
1232				const struct nfs_pgio_completion_ops *compl_ops)
1233{
1234	struct nfs_pageio_descriptor pgio;
1235	LIST_HEAD(failed);
1236
1237	/* Resend all requests through the MDS */
1238	nfs_pageio_init_write_mds(&pgio, inode, FLUSH_STABLE, compl_ops);
1239	while (!list_empty(head)) {
1240		struct nfs_page *req = nfs_list_entry(head->next);
1241
1242		nfs_list_remove_request(req);
1243		if (!nfs_pageio_add_request(&pgio, req))
1244			nfs_list_add_request(req, &failed);
1245	}
1246	nfs_pageio_complete(&pgio);
1247
1248	if (!list_empty(&failed)) {
1249		/* For some reason our attempt to resend pages. Mark the
1250		 * overall send request as having failed, and let
1251		 * nfs_writeback_release_full deal with the error.
1252		 */
1253		list_move(&failed, head);
1254		return -EIO;
1255	}
1256	return 0;
1257}
1258EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
1259
1260static void pnfs_ld_handle_write_error(struct nfs_write_data *data)
1261{
1262	struct nfs_pgio_header *hdr = data->header;
1263
1264	dprintk("pnfs write error = %d\n", hdr->pnfs_error);
1265	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
1266	    PNFS_LAYOUTRET_ON_ERROR) {
1267		clear_bit(NFS_INO_LAYOUTCOMMIT, &NFS_I(hdr->inode)->flags);
1268		pnfs_return_layout(hdr->inode);
1269	}
1270	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
1271		data->task.tk_status = pnfs_write_done_resend_to_mds(hdr->inode,
1272							&hdr->pages,
1273							hdr->completion_ops);
1274}
1275
1276/*
1277 * Called by non rpc-based layout drivers
1278 */
1279void pnfs_ld_write_done(struct nfs_write_data *data)
1280{
1281	struct nfs_pgio_header *hdr = data->header;
1282
1283	if (!hdr->pnfs_error) {
1284		pnfs_set_layoutcommit(data);
1285		hdr->mds_ops->rpc_call_done(&data->task, data);
1286	} else
1287		pnfs_ld_handle_write_error(data);
1288	hdr->mds_ops->rpc_release(data);
 
1289}
1290EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
1291
1292static void
1293pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
1294		struct nfs_write_data *data)
1295{
1296	struct nfs_pgio_header *hdr = data->header;
1297
1298	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1299		list_splice_tail_init(&hdr->pages, &desc->pg_list);
1300		nfs_pageio_reset_write_mds(desc);
1301		desc->pg_recoalesce = 1;
1302	}
1303	nfs_writedata_release(data);
1304}
1305
1306static enum pnfs_try_status
1307pnfs_try_to_write_data(struct nfs_write_data *wdata,
1308			const struct rpc_call_ops *call_ops,
1309			struct pnfs_layout_segment *lseg,
1310			int how)
1311{
1312	struct nfs_pgio_header *hdr = wdata->header;
1313	struct inode *inode = hdr->inode;
1314	enum pnfs_try_status trypnfs;
1315	struct nfs_server *nfss = NFS_SERVER(inode);
1316
1317	hdr->mds_ops = call_ops;
1318
1319	dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
1320		inode->i_ino, wdata->args.count, wdata->args.offset, how);
1321	trypnfs = nfss->pnfs_curr_ld->write_pagelist(wdata, how);
1322	if (trypnfs != PNFS_NOT_ATTEMPTED)
1323		nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
1324	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
1325	return trypnfs;
1326}
1327
1328static void
1329pnfs_do_multiple_writes(struct nfs_pageio_descriptor *desc, struct list_head *head, int how)
 
1330{
1331	struct nfs_write_data *data;
1332	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
1333	struct pnfs_layout_segment *lseg = desc->pg_lseg;
 
1334
1335	desc->pg_lseg = NULL;
1336	while (!list_empty(head)) {
1337		enum pnfs_try_status trypnfs;
1338
1339		data = list_first_entry(head, struct nfs_write_data, list);
1340		list_del_init(&data->list);
1341
1342		trypnfs = pnfs_try_to_write_data(data, call_ops, lseg, how);
1343		if (trypnfs == PNFS_NOT_ATTEMPTED)
1344			pnfs_write_through_mds(desc, data);
 
 
 
 
1345	}
1346	put_lseg(lseg);
1347}
1348
1349static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
1350{
1351	put_lseg(hdr->lseg);
1352	nfs_writehdr_free(hdr);
1353}
1354
1355int
1356pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
1357{
1358	struct nfs_write_header *whdr;
1359	struct nfs_pgio_header *hdr;
1360	int ret;
1361
1362	whdr = nfs_writehdr_alloc();
1363	if (!whdr) {
1364		desc->pg_completion_ops->error_cleanup(&desc->pg_list);
1365		put_lseg(desc->pg_lseg);
1366		desc->pg_lseg = NULL;
1367		return -ENOMEM;
1368	}
1369	hdr = &whdr->header;
1370	nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
1371	hdr->lseg = get_lseg(desc->pg_lseg);
1372	atomic_inc(&hdr->refcnt);
1373	ret = nfs_generic_flush(desc, hdr);
1374	if (ret != 0) {
1375		put_lseg(desc->pg_lseg);
1376		desc->pg_lseg = NULL;
1377	} else
1378		pnfs_do_multiple_writes(desc, &hdr->rpc_list, desc->pg_ioflags);
1379	if (atomic_dec_and_test(&hdr->refcnt))
1380		hdr->completion_ops->completion(hdr);
1381	return ret;
1382}
1383EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
1384
1385int pnfs_read_done_resend_to_mds(struct inode *inode,
1386				struct list_head *head,
1387				const struct nfs_pgio_completion_ops *compl_ops)
1388{
1389	struct nfs_pageio_descriptor pgio;
1390	LIST_HEAD(failed);
1391
1392	/* Resend all requests through the MDS */
1393	nfs_pageio_init_read_mds(&pgio, inode, compl_ops);
1394	while (!list_empty(head)) {
1395		struct nfs_page *req = nfs_list_entry(head->next);
1396
1397		nfs_list_remove_request(req);
1398		if (!nfs_pageio_add_request(&pgio, req))
1399			nfs_list_add_request(req, &failed);
1400	}
1401	nfs_pageio_complete(&pgio);
1402
1403	if (!list_empty(&failed)) {
1404		list_move(&failed, head);
1405		return -EIO;
1406	}
1407	return 0;
1408}
1409EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
1410
1411static void pnfs_ld_handle_read_error(struct nfs_read_data *data)
1412{
1413	struct nfs_pgio_header *hdr = data->header;
1414
1415	dprintk("pnfs read error = %d\n", hdr->pnfs_error);
1416	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
1417	    PNFS_LAYOUTRET_ON_ERROR) {
1418		clear_bit(NFS_INO_LAYOUTCOMMIT, &NFS_I(hdr->inode)->flags);
1419		pnfs_return_layout(hdr->inode);
1420	}
1421	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
1422		data->task.tk_status = pnfs_read_done_resend_to_mds(hdr->inode,
1423							&hdr->pages,
1424							hdr->completion_ops);
1425}
1426
1427/*
1428 * Called by non rpc-based layout drivers
1429 */
1430void pnfs_ld_read_done(struct nfs_read_data *data)
1431{
1432	struct nfs_pgio_header *hdr = data->header;
1433
1434	if (likely(!hdr->pnfs_error)) {
1435		__nfs4_read_done_cb(data);
1436		hdr->mds_ops->rpc_call_done(&data->task, data);
1437	} else
1438		pnfs_ld_handle_read_error(data);
1439	hdr->mds_ops->rpc_release(data);
1440}
1441EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
1442
1443static void
1444pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
1445		struct nfs_read_data *data)
1446{
1447	struct nfs_pgio_header *hdr = data->header;
1448
1449	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1450		list_splice_tail_init(&hdr->pages, &desc->pg_list);
1451		nfs_pageio_reset_read_mds(desc);
1452		desc->pg_recoalesce = 1;
1453	}
1454	nfs_readdata_release(data);
1455}
1456
1457/*
1458 * Call the appropriate parallel I/O subsystem read function.
1459 */
1460static enum pnfs_try_status
1461pnfs_try_to_read_data(struct nfs_read_data *rdata,
1462		       const struct rpc_call_ops *call_ops,
1463		       struct pnfs_layout_segment *lseg)
1464{
1465	struct nfs_pgio_header *hdr = rdata->header;
1466	struct inode *inode = hdr->inode;
1467	struct nfs_server *nfss = NFS_SERVER(inode);
1468	enum pnfs_try_status trypnfs;
1469
1470	hdr->mds_ops = call_ops;
1471
1472	dprintk("%s: Reading ino:%lu %u@%llu\n",
1473		__func__, inode->i_ino, rdata->args.count, rdata->args.offset);
1474
1475	trypnfs = nfss->pnfs_curr_ld->read_pagelist(rdata);
1476	if (trypnfs != PNFS_NOT_ATTEMPTED)
1477		nfs_inc_stats(inode, NFSIOS_PNFS_READ);
1478	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
1479	return trypnfs;
1480}
1481
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1482static void
1483pnfs_do_multiple_reads(struct nfs_pageio_descriptor *desc, struct list_head *head)
1484{
1485	struct nfs_read_data *data;
1486	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
1487	struct pnfs_layout_segment *lseg = desc->pg_lseg;
 
1488
1489	desc->pg_lseg = NULL;
1490	while (!list_empty(head)) {
1491		enum pnfs_try_status trypnfs;
1492
1493		data = list_first_entry(head, struct nfs_read_data, list);
1494		list_del_init(&data->list);
1495
1496		trypnfs = pnfs_try_to_read_data(data, call_ops, lseg);
1497		if (trypnfs == PNFS_NOT_ATTEMPTED)
1498			pnfs_read_through_mds(desc, data);
 
 
 
 
1499	}
1500	put_lseg(lseg);
1501}
1502
1503static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
1504{
1505	put_lseg(hdr->lseg);
1506	nfs_readhdr_free(hdr);
1507}
1508
1509int
1510pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
1511{
1512	struct nfs_read_header *rhdr;
1513	struct nfs_pgio_header *hdr;
1514	int ret;
1515
1516	rhdr = nfs_readhdr_alloc();
1517	if (!rhdr) {
1518		desc->pg_completion_ops->error_cleanup(&desc->pg_list);
1519		ret = -ENOMEM;
1520		put_lseg(desc->pg_lseg);
1521		desc->pg_lseg = NULL;
1522		return ret;
1523	}
1524	hdr = &rhdr->header;
1525	nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
1526	hdr->lseg = get_lseg(desc->pg_lseg);
1527	atomic_inc(&hdr->refcnt);
1528	ret = nfs_generic_pagein(desc, hdr);
1529	if (ret != 0) {
1530		put_lseg(desc->pg_lseg);
1531		desc->pg_lseg = NULL;
1532	} else
1533		pnfs_do_multiple_reads(desc, &hdr->rpc_list);
1534	if (atomic_dec_and_test(&hdr->refcnt))
1535		hdr->completion_ops->completion(hdr);
1536	return ret;
1537}
1538EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
1539
 
 
 
 
 
 
 
 
 
1540/*
1541 * There can be multiple RW segments.
1542 */
1543static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
1544{
1545	struct pnfs_layout_segment *lseg;
1546
1547	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
1548		if (lseg->pls_range.iomode == IOMODE_RW &&
1549		    test_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
1550			list_add(&lseg->pls_lc_list, listp);
1551	}
1552}
1553
 
 
 
 
 
 
 
 
 
 
 
 
 
1554void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
1555{
1556	if (lseg->pls_range.iomode == IOMODE_RW) {
1557		dprintk("%s Setting layout IOMODE_RW fail bit\n", __func__);
1558		set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
1559	} else {
1560		dprintk("%s Setting layout IOMODE_READ fail bit\n", __func__);
1561		set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
1562	}
1563}
1564EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
1565
1566void
1567pnfs_set_layoutcommit(struct nfs_write_data *wdata)
 
1568{
1569	struct nfs_pgio_header *hdr = wdata->header;
1570	struct inode *inode = hdr->inode;
1571	struct nfs_inode *nfsi = NFS_I(inode);
1572	loff_t end_pos = wdata->mds_offset + wdata->res.count;
1573	bool mark_as_dirty = false;
1574
1575	spin_lock(&inode->i_lock);
1576	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
 
1577		mark_as_dirty = true;
1578		dprintk("%s: Set layoutcommit for inode %lu ",
1579			__func__, inode->i_ino);
1580	}
1581	if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &hdr->lseg->pls_flags)) {
 
1582		/* references matched in nfs4_layoutcommit_release */
1583		get_lseg(hdr->lseg);
1584	}
1585	if (end_pos > nfsi->layout->plh_lwb)
1586		nfsi->layout->plh_lwb = end_pos;
1587	spin_unlock(&inode->i_lock);
1588	dprintk("%s: lseg %p end_pos %llu\n",
1589		__func__, hdr->lseg, nfsi->layout->plh_lwb);
1590
1591	/* if pnfs_layoutcommit_inode() runs between inode locks, the next one
1592	 * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */
1593	if (mark_as_dirty)
1594		mark_inode_dirty_sync(inode);
1595}
1596EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
1597
1598void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data)
1599{
1600	struct nfs_server *nfss = NFS_SERVER(data->args.inode);
1601
1602	if (nfss->pnfs_curr_ld->cleanup_layoutcommit)
1603		nfss->pnfs_curr_ld->cleanup_layoutcommit(data);
 
1604}
1605
1606/*
1607 * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
1608 * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
1609 * data to disk to allow the server to recover the data if it crashes.
1610 * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
1611 * is off, and a COMMIT is sent to a data server, or
1612 * if WRITEs to a data server return NFS_DATA_SYNC.
1613 */
1614int
1615pnfs_layoutcommit_inode(struct inode *inode, bool sync)
1616{
 
1617	struct nfs4_layoutcommit_data *data;
1618	struct nfs_inode *nfsi = NFS_I(inode);
1619	loff_t end_pos;
1620	int status = 0;
1621
1622	dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
1623
1624	if (!test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
1625		return 0;
1626
1627	/* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
1628	data = kzalloc(sizeof(*data), GFP_NOFS);
1629	if (!data) {
1630		status = -ENOMEM;
1631		goto out;
1632	}
1633
1634	if (!test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
1635		goto out_free;
1636
 
1637	if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
1638		if (!sync) {
1639			status = -EAGAIN;
1640			goto out_free;
1641		}
1642		status = wait_on_bit_lock(&nfsi->flags, NFS_INO_LAYOUTCOMMITTING,
1643					nfs_wait_bit_killable, TASK_KILLABLE);
1644		if (status)
1645			goto out_free;
1646	}
1647
1648	INIT_LIST_HEAD(&data->lseg_list);
 
 
 
 
 
 
1649	spin_lock(&inode->i_lock);
1650	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
1651		clear_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags);
1652		spin_unlock(&inode->i_lock);
1653		wake_up_bit(&nfsi->flags, NFS_INO_LAYOUTCOMMITTING);
1654		goto out_free;
1655	}
1656
 
1657	pnfs_list_write_lseg(inode, &data->lseg_list);
1658
1659	end_pos = nfsi->layout->plh_lwb;
1660	nfsi->layout->plh_lwb = 0;
1661
1662	nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
1663	spin_unlock(&inode->i_lock);
1664
1665	data->args.inode = inode;
1666	data->cred = get_rpccred(nfsi->layout->plh_lc_cred);
1667	nfs_fattr_init(&data->fattr);
1668	data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
1669	data->res.fattr = &data->fattr;
1670	data->args.lastbytewritten = end_pos - 1;
 
 
 
1671	data->res.server = NFS_SERVER(inode);
1672
 
 
 
 
 
 
 
 
 
 
 
 
 
1673	status = nfs4_proc_layoutcommit(data, sync);
1674out:
1675	if (status)
1676		mark_inode_dirty_sync(inode);
1677	dprintk("<-- %s status %d\n", __func__, status);
1678	return status;
1679out_free:
 
1680	kfree(data);
 
 
1681	goto out;
1682}
 
 
 
 
 
 
 
 
1683
1684struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
1685{
1686	struct nfs4_threshold *thp;
1687
1688	thp = kzalloc(sizeof(*thp), GFP_NOFS);
1689	if (!thp) {
1690		dprintk("%s mdsthreshold allocation failed\n", __func__);
1691		return NULL;
1692	}
1693	return thp;
1694}