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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);
v4.6
   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#include "nfs4trace.h"
  37#include "delegation.h"
  38#include "nfs42.h"
  39
  40#define NFSDBG_FACILITY		NFSDBG_PNFS
  41#define PNFS_LAYOUTGET_RETRY_TIMEOUT (120*HZ)
  42
  43/* Locking:
  44 *
  45 * pnfs_spinlock:
  46 *      protects pnfs_modules_tbl.
  47 */
  48static DEFINE_SPINLOCK(pnfs_spinlock);
  49
  50/*
  51 * pnfs_modules_tbl holds all pnfs modules
  52 */
  53static LIST_HEAD(pnfs_modules_tbl);
  54
  55static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo);
 
 
 
 
 
 
  56
  57/* Return the registered pnfs layout driver module matching given id */
  58static struct pnfs_layoutdriver_type *
  59find_pnfs_driver_locked(u32 id)
  60{
  61	struct pnfs_layoutdriver_type *local;
  62
  63	list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid)
  64		if (local->id == id)
  65			goto out;
  66	local = NULL;
  67out:
  68	dprintk("%s: Searching for id %u, found %p\n", __func__, id, local);
  69	return local;
  70}
  71
  72static struct pnfs_layoutdriver_type *
  73find_pnfs_driver(u32 id)
  74{
  75	struct pnfs_layoutdriver_type *local;
  76
  77	spin_lock(&pnfs_spinlock);
  78	local = find_pnfs_driver_locked(id);
  79	if (local != NULL && !try_module_get(local->owner)) {
  80		dprintk("%s: Could not grab reference on module\n", __func__);
  81		local = NULL;
  82	}
  83	spin_unlock(&pnfs_spinlock);
  84	return local;
  85}
  86
  87void
  88unset_pnfs_layoutdriver(struct nfs_server *nfss)
  89{
  90	if (nfss->pnfs_curr_ld) {
  91		if (nfss->pnfs_curr_ld->clear_layoutdriver)
  92			nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
  93		/* Decrement the MDS count. Purge the deviceid cache if zero */
  94		if (atomic_dec_and_test(&nfss->nfs_client->cl_mds_count))
  95			nfs4_deviceid_purge_client(nfss->nfs_client);
  96		module_put(nfss->pnfs_curr_ld->owner);
  97	}
  98	nfss->pnfs_curr_ld = NULL;
  99}
 100
 101/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 102 * Try to set the server's pnfs module to the pnfs layout type specified by id.
 103 * Currently only one pNFS layout driver per filesystem is supported.
 104 *
 105 * @id layout type. Zero (illegal layout type) indicates pNFS not in use.
 106 */
 107void
 108set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
 109		      u32 id)
 110{
 111	struct pnfs_layoutdriver_type *ld_type = NULL;
 
 
 112
 113	if (id == 0)
 114		goto out_no_driver;
 115	if (!(server->nfs_client->cl_exchange_flags &
 116		 (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
 117		printk(KERN_ERR "NFS: %s: id %u cl_exchange_flags 0x%x\n",
 118			__func__, id, server->nfs_client->cl_exchange_flags);
 119		goto out_no_driver;
 120	}
 121	ld_type = find_pnfs_driver(id);
 122	if (!ld_type) {
 123		request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX, id);
 
 
 
 124		ld_type = find_pnfs_driver(id);
 125		if (!ld_type) {
 126			dprintk("%s: No pNFS module found for %u.\n",
 127				__func__, id);
 128			goto out_no_driver;
 129		}
 
 
 
 
 
 
 
 130	}
 
 131	server->pnfs_curr_ld = ld_type;
 132	if (ld_type->set_layoutdriver
 133	    && ld_type->set_layoutdriver(server, mntfh)) {
 134		printk(KERN_ERR "NFS: %s: Error initializing pNFS layout "
 135			"driver %u.\n", __func__, id);
 136		module_put(ld_type->owner);
 137		goto out_no_driver;
 138	}
 139	/* Bump the MDS count */
 140	atomic_inc(&server->nfs_client->cl_mds_count);
 141
 142	dprintk("%s: pNFS module for %u set\n", __func__, id);
 143	return;
 144
 145out_no_driver:
 146	dprintk("%s: Using NFSv4 I/O\n", __func__);
 147	server->pnfs_curr_ld = NULL;
 148}
 149
 150int
 151pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 152{
 153	int status = -EINVAL;
 154	struct pnfs_layoutdriver_type *tmp;
 155
 156	if (ld_type->id == 0) {
 157		printk(KERN_ERR "NFS: %s id 0 is reserved\n", __func__);
 158		return status;
 159	}
 160	if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
 161		printk(KERN_ERR "NFS: %s Layout driver must provide "
 162		       "alloc_lseg and free_lseg.\n", __func__);
 163		return status;
 164	}
 165
 166	spin_lock(&pnfs_spinlock);
 167	tmp = find_pnfs_driver_locked(ld_type->id);
 168	if (!tmp) {
 169		list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
 170		status = 0;
 171		dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
 172			ld_type->name);
 173	} else {
 174		printk(KERN_ERR "NFS: %s Module with id %d already loaded!\n",
 175			__func__, ld_type->id);
 176	}
 177	spin_unlock(&pnfs_spinlock);
 178
 179	return status;
 180}
 181EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);
 182
 183void
 184pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 185{
 186	dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
 187	spin_lock(&pnfs_spinlock);
 188	list_del(&ld_type->pnfs_tblid);
 189	spin_unlock(&pnfs_spinlock);
 190}
 191EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
 192
 193/*
 194 * pNFS client layout cache
 195 */
 196
 197/* Need to hold i_lock if caller does not already hold reference */
 198void
 199pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo)
 200{
 201	atomic_inc(&lo->plh_refcount);
 202}
 203
 204static struct pnfs_layout_hdr *
 205pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags)
 206{
 207	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
 208	return ld->alloc_layout_hdr(ino, gfp_flags);
 209}
 210
 211static void
 212pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
 213{
 214	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
 215	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
 216
 217	if (!list_empty(&lo->plh_layouts)) {
 218		struct nfs_client *clp = server->nfs_client;
 219
 220		spin_lock(&clp->cl_lock);
 221		list_del_init(&lo->plh_layouts);
 222		spin_unlock(&clp->cl_lock);
 223	}
 224	put_rpccred(lo->plh_lc_cred);
 225	return ld->free_layout_hdr(lo);
 226}
 227
 228static void
 229pnfs_detach_layout_hdr(struct pnfs_layout_hdr *lo)
 230{
 231	struct nfs_inode *nfsi = NFS_I(lo->plh_inode);
 232	dprintk("%s: freeing layout cache %p\n", __func__, lo);
 233	nfsi->layout = NULL;
 234	/* Reset MDS Threshold I/O counters */
 235	nfsi->write_io = 0;
 236	nfsi->read_io = 0;
 237}
 238
 239void
 240pnfs_put_layout_hdr(struct pnfs_layout_hdr *lo)
 241{
 242	struct inode *inode = lo->plh_inode;
 243
 
 
 
 244	pnfs_layoutreturn_before_put_layout_hdr(lo);
 245
 246	if (atomic_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
 247		if (!list_empty(&lo->plh_segs))
 248			WARN_ONCE(1, "NFS: BUG unfreed layout segments.\n");
 249		pnfs_detach_layout_hdr(lo);
 250		spin_unlock(&inode->i_lock);
 251		pnfs_free_layout_hdr(lo);
 252	}
 253}
 254
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 255/*
 256 * Mark a pnfs_layout_hdr and all associated layout segments as invalid
 257 *
 258 * In order to continue using the pnfs_layout_hdr, a full recovery
 259 * is required.
 260 * Note that caller must hold inode->i_lock.
 261 */
 262static int
 263pnfs_mark_layout_stateid_invalid(struct pnfs_layout_hdr *lo,
 264		struct list_head *lseg_list)
 265{
 266	struct pnfs_layout_range range = {
 267		.iomode = IOMODE_ANY,
 268		.offset = 0,
 269		.length = NFS4_MAX_UINT64,
 270	};
 
 271
 272	set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 273	return pnfs_mark_matching_lsegs_invalid(lo, lseg_list, &range);
 
 
 
 
 
 
 
 274}
 275
 276static int
 277pnfs_iomode_to_fail_bit(u32 iomode)
 278{
 279	return iomode == IOMODE_RW ?
 280		NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 281}
 282
 283static void
 284pnfs_layout_set_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 285{
 286	lo->plh_retry_timestamp = jiffies;
 287	if (!test_and_set_bit(fail_bit, &lo->plh_flags))
 288		atomic_inc(&lo->plh_refcount);
 289}
 290
 291static void
 292pnfs_layout_clear_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 293{
 294	if (test_and_clear_bit(fail_bit, &lo->plh_flags))
 295		atomic_dec(&lo->plh_refcount);
 296}
 297
 298static void
 299pnfs_layout_io_set_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 300{
 301	struct inode *inode = lo->plh_inode;
 302	struct pnfs_layout_range range = {
 303		.iomode = iomode,
 304		.offset = 0,
 305		.length = NFS4_MAX_UINT64,
 306	};
 307	LIST_HEAD(head);
 308
 309	spin_lock(&inode->i_lock);
 310	pnfs_layout_set_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
 311	pnfs_mark_matching_lsegs_invalid(lo, &head, &range);
 312	spin_unlock(&inode->i_lock);
 313	pnfs_free_lseg_list(&head);
 314	dprintk("%s Setting layout IOMODE_%s fail bit\n", __func__,
 315			iomode == IOMODE_RW ?  "RW" : "READ");
 316}
 317
 318static bool
 319pnfs_layout_io_test_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 320{
 321	unsigned long start, end;
 322	int fail_bit = pnfs_iomode_to_fail_bit(iomode);
 323
 324	if (test_bit(fail_bit, &lo->plh_flags) == 0)
 325		return false;
 326	end = jiffies;
 327	start = end - PNFS_LAYOUTGET_RETRY_TIMEOUT;
 328	if (!time_in_range(lo->plh_retry_timestamp, start, end)) {
 329		/* It is time to retry the failed layoutgets */
 330		pnfs_layout_clear_fail_bit(lo, fail_bit);
 331		return false;
 332	}
 333	return true;
 334}
 335
 336static void
 337init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg)
 
 
 338{
 339	INIT_LIST_HEAD(&lseg->pls_list);
 340	INIT_LIST_HEAD(&lseg->pls_lc_list);
 341	atomic_set(&lseg->pls_refcount, 1);
 342	smp_mb();
 343	set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
 344	lseg->pls_layout = lo;
 
 
 345}
 346
 347static void pnfs_free_lseg(struct pnfs_layout_segment *lseg)
 348{
 349	struct inode *ino = lseg->pls_layout->plh_inode;
 350
 351	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
 
 352}
 353
 354static void
 355pnfs_layout_remove_lseg(struct pnfs_layout_hdr *lo,
 356		struct pnfs_layout_segment *lseg)
 357{
 358	struct inode *inode = lo->plh_inode;
 359
 360	WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 361	list_del_init(&lseg->pls_list);
 362	/* Matched by pnfs_get_layout_hdr in pnfs_layout_insert_lseg */
 363	atomic_dec(&lo->plh_refcount);
 364	if (list_empty(&lo->plh_segs))
 
 
 
 
 
 
 365		clear_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 366	rpc_wake_up(&NFS_SERVER(inode)->roc_rpcwaitq);
 
 
 
 
 
 
 
 
 
 
 
 
 
 367}
 368
 369void
 370pnfs_put_lseg(struct pnfs_layout_segment *lseg)
 371{
 372	struct pnfs_layout_hdr *lo;
 373	struct inode *inode;
 374
 375	if (!lseg)
 376		return;
 377
 378	dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
 379		atomic_read(&lseg->pls_refcount),
 380		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 381
 382	lo = lseg->pls_layout;
 383	inode = lo->plh_inode;
 384
 385	if (atomic_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
 386		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 387			spin_unlock(&inode->i_lock);
 388			return;
 389		}
 390		pnfs_get_layout_hdr(lo);
 391		pnfs_layout_remove_lseg(lo, lseg);
 
 
 392		spin_unlock(&inode->i_lock);
 393		pnfs_free_lseg(lseg);
 394		pnfs_put_layout_hdr(lo);
 395	}
 396}
 397EXPORT_SYMBOL_GPL(pnfs_put_lseg);
 398
 399static void pnfs_free_lseg_async_work(struct work_struct *work)
 400{
 401	struct pnfs_layout_segment *lseg;
 402	struct pnfs_layout_hdr *lo;
 403
 404	lseg = container_of(work, struct pnfs_layout_segment, pls_work);
 405	lo = lseg->pls_layout;
 406
 407	pnfs_free_lseg(lseg);
 408	pnfs_put_layout_hdr(lo);
 409}
 410
 411static void pnfs_free_lseg_async(struct pnfs_layout_segment *lseg)
 412{
 413	INIT_WORK(&lseg->pls_work, pnfs_free_lseg_async_work);
 414	schedule_work(&lseg->pls_work);
 415}
 416
 417void
 418pnfs_put_lseg_locked(struct pnfs_layout_segment *lseg)
 419{
 420	if (!lseg)
 421		return;
 422
 423	assert_spin_locked(&lseg->pls_layout->plh_inode->i_lock);
 424
 425	dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
 426		atomic_read(&lseg->pls_refcount),
 427		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 428	if (atomic_dec_and_test(&lseg->pls_refcount)) {
 429		struct pnfs_layout_hdr *lo = lseg->pls_layout;
 430		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags))
 431			return;
 432		pnfs_get_layout_hdr(lo);
 433		pnfs_layout_remove_lseg(lo, lseg);
 434		pnfs_free_lseg_async(lseg);
 435	}
 436}
 437EXPORT_SYMBOL_GPL(pnfs_put_lseg_locked);
 438
 439static u64
 440end_offset(u64 start, u64 len)
 441{
 442	u64 end;
 443
 444	end = start + len;
 445	return end >= start ? end : NFS4_MAX_UINT64;
 446}
 447
 448/*
 449 * is l2 fully contained in l1?
 450 *   start1                             end1
 451 *   [----------------------------------)
 452 *           start2           end2
 453 *           [----------------)
 454 */
 455static bool
 456pnfs_lseg_range_contained(const struct pnfs_layout_range *l1,
 457		 const struct pnfs_layout_range *l2)
 458{
 459	u64 start1 = l1->offset;
 460	u64 end1 = end_offset(start1, l1->length);
 461	u64 start2 = l2->offset;
 462	u64 end2 = end_offset(start2, l2->length);
 463
 464	return (start1 <= start2) && (end1 >= end2);
 465}
 466
 467/*
 468 * is l1 and l2 intersecting?
 469 *   start1                             end1
 470 *   [----------------------------------)
 471 *                              start2           end2
 472 *                              [----------------)
 473 */
 474static bool
 475pnfs_lseg_range_intersecting(const struct pnfs_layout_range *l1,
 476		    const struct pnfs_layout_range *l2)
 477{
 478	u64 start1 = l1->offset;
 479	u64 end1 = end_offset(start1, l1->length);
 480	u64 start2 = l2->offset;
 481	u64 end2 = end_offset(start2, l2->length);
 482
 483	return (end1 == NFS4_MAX_UINT64 || end1 > start2) &&
 484	       (end2 == NFS4_MAX_UINT64 || end2 > start1);
 485}
 486
 487static bool
 488should_free_lseg(const struct pnfs_layout_range *lseg_range,
 489		 const struct pnfs_layout_range *recall_range)
 490{
 491	return (recall_range->iomode == IOMODE_ANY ||
 492		lseg_range->iomode == recall_range->iomode) &&
 493	       pnfs_lseg_range_intersecting(lseg_range, recall_range);
 494}
 495
 496static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
 497		struct list_head *tmp_list)
 498{
 499	if (!atomic_dec_and_test(&lseg->pls_refcount))
 500		return false;
 501	pnfs_layout_remove_lseg(lseg->pls_layout, lseg);
 502	list_add(&lseg->pls_list, tmp_list);
 503	return true;
 504}
 505
 506/* Returns 1 if lseg is removed from list, 0 otherwise */
 507static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
 508			     struct list_head *tmp_list)
 509{
 510	int rv = 0;
 511
 512	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 513		/* Remove the reference keeping the lseg in the
 514		 * list.  It will now be removed when all
 515		 * outstanding io is finished.
 516		 */
 517		dprintk("%s: lseg %p ref %d\n", __func__, lseg,
 518			atomic_read(&lseg->pls_refcount));
 519		if (pnfs_lseg_dec_and_remove_zero(lseg, tmp_list))
 520			rv = 1;
 521	}
 522	return rv;
 523}
 524
 525/* Returns count of number of matching invalid lsegs remaining in list
 526 * after call.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 527 */
 528int
 529pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 530			    struct list_head *tmp_list,
 531			    const struct pnfs_layout_range *recall_range)
 
 532{
 533	struct pnfs_layout_segment *lseg, *next;
 534	int remaining = 0;
 535
 536	dprintk("%s:Begin lo %p\n", __func__, lo);
 537
 538	if (list_empty(&lo->plh_segs))
 539		return 0;
 540	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 541		if (!recall_range ||
 542		    should_free_lseg(&lseg->pls_range, recall_range)) {
 543			dprintk("%s: freeing lseg %p iomode %d "
 544				"offset %llu length %llu\n", __func__,
 545				lseg, lseg->pls_range.iomode, lseg->pls_range.offset,
 546				lseg->pls_range.length);
 547			if (!mark_lseg_invalid(lseg, tmp_list))
 548				remaining++;
 549		}
 550	dprintk("%s:Return %i\n", __func__, remaining);
 551	return remaining;
 552}
 553
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 554/* note free_me must contain lsegs from a single layout_hdr */
 555void
 556pnfs_free_lseg_list(struct list_head *free_me)
 557{
 558	struct pnfs_layout_segment *lseg, *tmp;
 559
 560	if (list_empty(free_me))
 561		return;
 562
 563	list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
 564		list_del(&lseg->pls_list);
 565		pnfs_free_lseg(lseg);
 566	}
 567}
 568
 569void
 570pnfs_destroy_layout(struct nfs_inode *nfsi)
 571{
 572	struct pnfs_layout_hdr *lo;
 573	LIST_HEAD(tmp_list);
 574
 575	spin_lock(&nfsi->vfs_inode.i_lock);
 576	lo = nfsi->layout;
 577	if (lo) {
 578		pnfs_get_layout_hdr(lo);
 579		pnfs_mark_layout_stateid_invalid(lo, &tmp_list);
 580		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RO_FAILED);
 581		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RW_FAILED);
 582		spin_unlock(&nfsi->vfs_inode.i_lock);
 583		pnfs_free_lseg_list(&tmp_list);
 
 584		pnfs_put_layout_hdr(lo);
 585	} else
 586		spin_unlock(&nfsi->vfs_inode.i_lock);
 587}
 588EXPORT_SYMBOL_GPL(pnfs_destroy_layout);
 589
 590static bool
 591pnfs_layout_add_bulk_destroy_list(struct inode *inode,
 592		struct list_head *layout_list)
 593{
 594	struct pnfs_layout_hdr *lo;
 595	bool ret = false;
 596
 597	spin_lock(&inode->i_lock);
 598	lo = NFS_I(inode)->layout;
 599	if (lo != NULL && list_empty(&lo->plh_bulk_destroy)) {
 600		pnfs_get_layout_hdr(lo);
 601		list_add(&lo->plh_bulk_destroy, layout_list);
 602		ret = true;
 603	}
 604	spin_unlock(&inode->i_lock);
 605	return ret;
 606}
 607
 608/* Caller must hold rcu_read_lock and clp->cl_lock */
 609static int
 610pnfs_layout_bulk_destroy_byserver_locked(struct nfs_client *clp,
 611		struct nfs_server *server,
 612		struct list_head *layout_list)
 613{
 614	struct pnfs_layout_hdr *lo, *next;
 615	struct inode *inode;
 616
 617	list_for_each_entry_safe(lo, next, &server->layouts, plh_layouts) {
 
 
 618		inode = igrab(lo->plh_inode);
 619		if (inode == NULL)
 620			continue;
 621		list_del_init(&lo->plh_layouts);
 622		if (pnfs_layout_add_bulk_destroy_list(inode, layout_list))
 623			continue;
 624		rcu_read_unlock();
 625		spin_unlock(&clp->cl_lock);
 626		iput(inode);
 627		spin_lock(&clp->cl_lock);
 628		rcu_read_lock();
 629		return -EAGAIN;
 630	}
 631	return 0;
 632}
 633
 634static int
 635pnfs_layout_free_bulk_destroy_list(struct list_head *layout_list,
 636		bool is_bulk_recall)
 637{
 638	struct pnfs_layout_hdr *lo;
 639	struct inode *inode;
 640	LIST_HEAD(lseg_list);
 641	int ret = 0;
 642
 643	while (!list_empty(layout_list)) {
 644		lo = list_entry(layout_list->next, struct pnfs_layout_hdr,
 645				plh_bulk_destroy);
 646		dprintk("%s freeing layout for inode %lu\n", __func__,
 647			lo->plh_inode->i_ino);
 648		inode = lo->plh_inode;
 649
 650		pnfs_layoutcommit_inode(inode, false);
 651
 652		spin_lock(&inode->i_lock);
 653		list_del_init(&lo->plh_bulk_destroy);
 654		if (pnfs_mark_layout_stateid_invalid(lo, &lseg_list)) {
 655			if (is_bulk_recall)
 656				set_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 657			ret = -EAGAIN;
 658		}
 659		spin_unlock(&inode->i_lock);
 660		pnfs_free_lseg_list(&lseg_list);
 661		/* Free all lsegs that are attached to commit buckets */
 662		nfs_commit_inode(inode, 0);
 663		pnfs_put_layout_hdr(lo);
 664		iput(inode);
 665	}
 666	return ret;
 667}
 668
 669int
 670pnfs_destroy_layouts_byfsid(struct nfs_client *clp,
 671		struct nfs_fsid *fsid,
 672		bool is_recall)
 673{
 674	struct nfs_server *server;
 675	LIST_HEAD(layout_list);
 676
 677	spin_lock(&clp->cl_lock);
 678	rcu_read_lock();
 679restart:
 680	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 681		if (memcmp(&server->fsid, fsid, sizeof(*fsid)) != 0)
 682			continue;
 683		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 684				server,
 685				&layout_list) != 0)
 686			goto restart;
 687	}
 688	rcu_read_unlock();
 689	spin_unlock(&clp->cl_lock);
 690
 691	if (list_empty(&layout_list))
 692		return 0;
 693	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 694}
 695
 696int
 697pnfs_destroy_layouts_byclid(struct nfs_client *clp,
 698		bool is_recall)
 699{
 700	struct nfs_server *server;
 701	LIST_HEAD(layout_list);
 702
 703	spin_lock(&clp->cl_lock);
 704	rcu_read_lock();
 705restart:
 706	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 707		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 708					server,
 709					&layout_list) != 0)
 710			goto restart;
 711	}
 712	rcu_read_unlock();
 713	spin_unlock(&clp->cl_lock);
 714
 715	if (list_empty(&layout_list))
 716		return 0;
 717	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 718}
 719
 720/*
 721 * Called by the state manger to remove all layouts established under an
 722 * expired lease.
 723 */
 724void
 725pnfs_destroy_all_layouts(struct nfs_client *clp)
 726{
 727	nfs4_deviceid_mark_client_invalid(clp);
 728	nfs4_deviceid_purge_client(clp);
 729
 730	pnfs_destroy_layouts_byclid(clp, false);
 731}
 732
 733/*
 734 * Compare 2 layout stateid sequence ids, to see which is newer,
 735 * taking into account wraparound issues.
 736 */
 737static bool pnfs_seqid_is_newer(u32 s1, u32 s2)
 738{
 739	return (s32)(s1 - s2) > 0;
 740}
 741
 742/* update lo->plh_stateid with new if is more recent */
 743void
 744pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
 745			bool update_barrier)
 746{
 747	u32 oldseq, newseq, new_barrier;
 748	int empty = list_empty(&lo->plh_segs);
 749
 750	oldseq = be32_to_cpu(lo->plh_stateid.seqid);
 751	newseq = be32_to_cpu(new->seqid);
 752	if (empty || pnfs_seqid_is_newer(newseq, oldseq)) {
 
 
 
 
 
 
 
 
 753		nfs4_stateid_copy(&lo->plh_stateid, new);
 754		if (update_barrier) {
 755			new_barrier = be32_to_cpu(new->seqid);
 756		} else {
 757			/* Because of wraparound, we want to keep the barrier
 758			 * "close" to the current seqids.
 759			 */
 760			new_barrier = newseq - atomic_read(&lo->plh_outstanding);
 761		}
 762		if (empty || pnfs_seqid_is_newer(new_barrier, lo->plh_barrier))
 763			lo->plh_barrier = new_barrier;
 764	}
 
 
 
 
 
 
 765}
 766
 767static bool
 768pnfs_layout_stateid_blocked(const struct pnfs_layout_hdr *lo,
 769		const nfs4_stateid *stateid)
 770{
 771	u32 seqid = be32_to_cpu(stateid->seqid);
 772
 773	return !pnfs_seqid_is_newer(seqid, lo->plh_barrier);
 774}
 775
 776/* lget is set to 1 if called from inside send_layoutget call chain */
 777static bool
 778pnfs_layoutgets_blocked(const struct pnfs_layout_hdr *lo)
 779{
 780	return lo->plh_block_lgets ||
 781		test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 782}
 783
 784int
 785pnfs_choose_layoutget_stateid(nfs4_stateid *dst, struct pnfs_layout_hdr *lo,
 786			      const struct pnfs_layout_range *range,
 787			      struct nfs4_state *open_state)
 788{
 789	int status = 0;
 790
 791	dprintk("--> %s\n", __func__);
 792	spin_lock(&lo->plh_inode->i_lock);
 793	if (pnfs_layoutgets_blocked(lo)) {
 794		status = -EAGAIN;
 795	} else if (!nfs4_valid_open_stateid(open_state)) {
 796		status = -EBADF;
 797	} else if (list_empty(&lo->plh_segs) ||
 798		   test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags)) {
 799		int seq;
 800
 801		do {
 802			seq = read_seqbegin(&open_state->seqlock);
 803			nfs4_stateid_copy(dst, &open_state->stateid);
 804		} while (read_seqretry(&open_state->seqlock, seq));
 805	} else
 806		nfs4_stateid_copy(dst, &lo->plh_stateid);
 807	spin_unlock(&lo->plh_inode->i_lock);
 808	dprintk("<-- %s\n", __func__);
 809	return status;
 810}
 811
 812/*
 813* Get layout from server.
 814*    for now, assume that whole file layouts are requested.
 815*    arg->offset: 0
 816*    arg->length: all ones
 817*/
 818static struct pnfs_layout_segment *
 819send_layoutget(struct pnfs_layout_hdr *lo,
 820	   struct nfs_open_context *ctx,
 
 821	   const struct pnfs_layout_range *range,
 822	   gfp_t gfp_flags)
 823{
 824	struct inode *ino = lo->plh_inode;
 825	struct nfs_server *server = NFS_SERVER(ino);
 826	struct nfs4_layoutget *lgp;
 827	struct pnfs_layout_segment *lseg;
 828	loff_t i_size;
 829
 830	dprintk("--> %s\n", __func__);
 831
 832	/*
 833	 * Synchronously retrieve layout information from server and
 834	 * store in lseg. If we race with a concurrent seqid morphing
 835	 * op, then re-send the LAYOUTGET.
 836	 */
 837	do {
 838		lgp = kzalloc(sizeof(*lgp), gfp_flags);
 839		if (lgp == NULL)
 840			return NULL;
 841
 842		i_size = i_size_read(ino);
 843
 844		lgp->args.minlength = PAGE_SIZE;
 845		if (lgp->args.minlength > range->length)
 846			lgp->args.minlength = range->length;
 847		if (range->iomode == IOMODE_READ) {
 848			if (range->offset >= i_size)
 849				lgp->args.minlength = 0;
 850			else if (i_size - range->offset < lgp->args.minlength)
 851				lgp->args.minlength = i_size - range->offset;
 852		}
 853		lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
 854		pnfs_copy_range(&lgp->args.range, range);
 855		lgp->args.type = server->pnfs_curr_ld->id;
 856		lgp->args.inode = ino;
 857		lgp->args.ctx = get_nfs_open_context(ctx);
 858		lgp->gfp_flags = gfp_flags;
 859		lgp->cred = lo->plh_lc_cred;
 860
 861		lseg = nfs4_proc_layoutget(lgp, gfp_flags);
 862	} while (lseg == ERR_PTR(-EAGAIN));
 863
 864	if (IS_ERR(lseg) && !nfs_error_is_fatal(PTR_ERR(lseg)))
 865		lseg = NULL;
 866	else
 867		pnfs_layout_clear_fail_bit(lo,
 868				pnfs_iomode_to_fail_bit(range->iomode));
 869
 870	return lseg;
 871}
 872
 873static void pnfs_clear_layoutcommit(struct inode *inode,
 874		struct list_head *head)
 875{
 876	struct nfs_inode *nfsi = NFS_I(inode);
 877	struct pnfs_layout_segment *lseg, *tmp;
 878
 879	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
 880		return;
 881	list_for_each_entry_safe(lseg, tmp, &nfsi->layout->plh_segs, pls_list) {
 882		if (!test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
 883			continue;
 884		pnfs_lseg_dec_and_remove_zero(lseg, head);
 885	}
 886}
 887
 888void pnfs_clear_layoutreturn_waitbit(struct pnfs_layout_hdr *lo)
 
 
 
 889{
 890	clear_bit_unlock(NFS_LAYOUT_RETURN, &lo->plh_flags);
 891	smp_mb__after_atomic();
 892	wake_up_bit(&lo->plh_flags, NFS_LAYOUT_RETURN);
 893	rpc_wake_up(&NFS_SERVER(lo->plh_inode)->roc_rpcwaitq);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 894}
 895
 896static bool
 897pnfs_prepare_layoutreturn(struct pnfs_layout_hdr *lo)
 
 
 898{
 899	if (test_and_set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
 
 
 
 900		return false;
 901	lo->plh_return_iomode = 0;
 902	pnfs_get_layout_hdr(lo);
 903	clear_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 904	return true;
 905}
 906
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 907static int
 908pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo, const nfs4_stateid *stateid,
 909		       enum pnfs_iomode iomode, bool sync)
 910{
 911	struct inode *ino = lo->plh_inode;
 
 912	struct nfs4_layoutreturn *lrp;
 913	int status = 0;
 914
 915	lrp = kzalloc(sizeof(*lrp), GFP_NOFS);
 916	if (unlikely(lrp == NULL)) {
 917		status = -ENOMEM;
 918		spin_lock(&ino->i_lock);
 919		pnfs_clear_layoutreturn_waitbit(lo);
 920		spin_unlock(&ino->i_lock);
 921		pnfs_put_layout_hdr(lo);
 922		goto out;
 923	}
 924
 925	nfs4_stateid_copy(&lrp->args.stateid, stateid);
 926	lrp->args.layout_type = NFS_SERVER(ino)->pnfs_curr_ld->id;
 927	lrp->args.inode = ino;
 928	lrp->args.range.iomode = iomode;
 929	lrp->args.range.offset = 0;
 930	lrp->args.range.length = NFS4_MAX_UINT64;
 931	lrp->args.layout = lo;
 932	lrp->clp = NFS_SERVER(ino)->nfs_client;
 933	lrp->cred = lo->plh_lc_cred;
 
 
 934
 935	status = nfs4_proc_layoutreturn(lrp, sync);
 936out:
 937	dprintk("<-- %s status: %d\n", __func__, status);
 938	return status;
 939}
 940
 941/* Return true if layoutreturn is needed */
 942static bool
 943pnfs_layout_need_return(struct pnfs_layout_hdr *lo)
 944{
 945	struct pnfs_layout_segment *s;
 946
 947	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
 948		return false;
 949
 950	/* Defer layoutreturn until all lsegs are done */
 951	list_for_each_entry(s, &lo->plh_segs, pls_list) {
 952		if (test_bit(NFS_LSEG_LAYOUTRETURN, &s->pls_flags))
 953			return false;
 954	}
 955
 956	return true;
 957}
 958
 959static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo)
 960{
 961	struct inode *inode= lo->plh_inode;
 962
 963	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
 964		return;
 965	spin_lock(&inode->i_lock);
 966	if (pnfs_layout_need_return(lo)) {
 967		nfs4_stateid stateid;
 968		enum pnfs_iomode iomode;
 969		bool send;
 970
 971		nfs4_stateid_copy(&stateid, &lo->plh_stateid);
 972		iomode = lo->plh_return_iomode;
 973		send = pnfs_prepare_layoutreturn(lo);
 974		spin_unlock(&inode->i_lock);
 975		if (send) {
 976			/* Send an async layoutreturn so we dont deadlock */
 977			pnfs_send_layoutreturn(lo, &stateid, iomode, false);
 978		}
 979	} else
 980		spin_unlock(&inode->i_lock);
 981}
 982
 983/*
 984 * Initiates a LAYOUTRETURN(FILE), and removes the pnfs_layout_hdr
 985 * when the layout segment list is empty.
 986 *
 987 * Note that a pnfs_layout_hdr can exist with an empty layout segment
 988 * list when LAYOUTGET has failed, or when LAYOUTGET succeeded, but the
 989 * deviceid is marked invalid.
 990 */
 991int
 992_pnfs_return_layout(struct inode *ino)
 993{
 994	struct pnfs_layout_hdr *lo = NULL;
 995	struct nfs_inode *nfsi = NFS_I(ino);
 996	LIST_HEAD(tmp_list);
 997	nfs4_stateid stateid;
 998	int status = 0, empty;
 999	bool send;
1000
1001	dprintk("NFS: %s for inode %lu\n", __func__, ino->i_ino);
1002
1003	spin_lock(&ino->i_lock);
1004	lo = nfsi->layout;
1005	if (!lo) {
1006		spin_unlock(&ino->i_lock);
1007		dprintk("NFS: %s no layout to return\n", __func__);
1008		goto out;
1009	}
1010	nfs4_stateid_copy(&stateid, &nfsi->layout->plh_stateid);
1011	/* Reference matched in nfs4_layoutreturn_release */
1012	pnfs_get_layout_hdr(lo);
1013	empty = list_empty(&lo->plh_segs);
 
 
 
 
 
 
 
1014	pnfs_clear_layoutcommit(ino, &tmp_list);
1015	pnfs_mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
1016
1017	if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) {
1018		struct pnfs_layout_range range = {
1019			.iomode		= IOMODE_ANY,
1020			.offset		= 0,
1021			.length		= NFS4_MAX_UINT64,
1022		};
1023		NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo, &range);
1024	}
1025
1026	/* Don't send a LAYOUTRETURN if list was initially empty */
1027	if (empty) {
1028		spin_unlock(&ino->i_lock);
1029		dprintk("NFS: %s no layout segments to return\n", __func__);
1030		goto out_put_layout_hdr;
1031	}
1032
1033	set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
1034	send = pnfs_prepare_layoutreturn(lo);
1035	spin_unlock(&ino->i_lock);
1036	pnfs_free_lseg_list(&tmp_list);
1037	if (send)
1038		status = pnfs_send_layoutreturn(lo, &stateid, IOMODE_ANY, true);
1039out_put_layout_hdr:
 
1040	pnfs_put_layout_hdr(lo);
1041out:
1042	dprintk("<-- %s status: %d\n", __func__, status);
1043	return status;
1044}
1045EXPORT_SYMBOL_GPL(_pnfs_return_layout);
1046
1047int
1048pnfs_commit_and_return_layout(struct inode *inode)
1049{
1050	struct pnfs_layout_hdr *lo;
1051	int ret;
1052
1053	spin_lock(&inode->i_lock);
1054	lo = NFS_I(inode)->layout;
1055	if (lo == NULL) {
1056		spin_unlock(&inode->i_lock);
1057		return 0;
1058	}
1059	pnfs_get_layout_hdr(lo);
1060	/* Block new layoutgets and read/write to ds */
1061	lo->plh_block_lgets++;
1062	spin_unlock(&inode->i_lock);
1063	filemap_fdatawait(inode->i_mapping);
1064	ret = pnfs_layoutcommit_inode(inode, true);
1065	if (ret == 0)
1066		ret = _pnfs_return_layout(inode);
1067	spin_lock(&inode->i_lock);
1068	lo->plh_block_lgets--;
1069	spin_unlock(&inode->i_lock);
1070	pnfs_put_layout_hdr(lo);
1071	return ret;
1072}
1073
1074bool pnfs_roc(struct inode *ino)
 
 
 
1075{
1076	struct nfs_inode *nfsi = NFS_I(ino);
1077	struct nfs_open_context *ctx;
1078	struct nfs4_state *state;
1079	struct pnfs_layout_hdr *lo;
1080	struct pnfs_layout_segment *lseg, *tmp;
1081	nfs4_stateid stateid;
1082	LIST_HEAD(tmp_list);
1083	bool found = false, layoutreturn = false, roc = false;
 
1084
 
 
 
1085	spin_lock(&ino->i_lock);
1086	lo = nfsi->layout;
1087	if (!lo || test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags))
 
 
1088		goto out_noroc;
 
 
 
 
 
 
 
 
 
1089
1090	/* no roc if we hold a delegation */
1091	if (nfs4_check_delegation(ino, FMODE_READ))
1092		goto out_noroc;
 
 
 
1093
1094	list_for_each_entry(ctx, &nfsi->open_files, list) {
1095		state = ctx->state;
 
 
1096		/* Don't return layout if there is open file state */
1097		if (state != NULL && state->state != 0)
1098			goto out_noroc;
 
 
1099	}
1100
1101	nfs4_stateid_copy(&stateid, &lo->plh_stateid);
1102	/* always send layoutreturn if being marked so */
1103	if (test_and_clear_bit(NFS_LAYOUT_RETURN_REQUESTED,
1104				   &lo->plh_flags))
1105		layoutreturn = pnfs_prepare_layoutreturn(lo);
1106
1107	list_for_each_entry_safe(lseg, tmp, &lo->plh_segs, pls_list)
 
 
1108		/* If we are sending layoutreturn, invalidate all valid lsegs */
1109		if (layoutreturn || test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
1110			mark_lseg_invalid(lseg, &tmp_list);
1111			found = true;
1112		}
 
 
 
 
 
 
 
 
 
 
 
1113	/* ROC in two conditions:
1114	 * 1. there are ROC lsegs
1115	 * 2. we don't send layoutreturn
1116	 */
1117	if (found && !layoutreturn) {
1118		/* lo ref dropped in pnfs_roc_release() */
1119		pnfs_get_layout_hdr(lo);
1120		roc = true;
1121	}
 
 
 
 
 
1122
1123out_noroc:
1124	spin_unlock(&ino->i_lock);
1125	pnfs_free_lseg_list(&tmp_list);
1126	pnfs_layoutcommit_inode(ino, true);
 
 
 
 
 
 
 
1127	if (layoutreturn)
1128		pnfs_send_layoutreturn(lo, &stateid, IOMODE_ANY, true);
1129	return roc;
 
1130}
1131
1132void pnfs_roc_release(struct inode *ino)
1133{
1134	struct pnfs_layout_hdr *lo;
1135
1136	spin_lock(&ino->i_lock);
1137	lo = NFS_I(ino)->layout;
1138	pnfs_clear_layoutreturn_waitbit(lo);
1139	if (atomic_dec_and_test(&lo->plh_refcount)) {
1140		pnfs_detach_layout_hdr(lo);
1141		spin_unlock(&ino->i_lock);
1142		pnfs_free_layout_hdr(lo);
1143	} else
1144		spin_unlock(&ino->i_lock);
1145}
1146
1147void pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
1148{
1149	struct pnfs_layout_hdr *lo;
1150
1151	spin_lock(&ino->i_lock);
1152	lo = NFS_I(ino)->layout;
1153	pnfs_mark_layout_returned_if_empty(lo);
1154	if (pnfs_seqid_is_newer(barrier, lo->plh_barrier))
1155		lo->plh_barrier = barrier;
1156	spin_unlock(&ino->i_lock);
1157	trace_nfs4_layoutreturn_on_close(ino, 0);
1158}
1159
1160void pnfs_roc_get_barrier(struct inode *ino, u32 *barrier)
1161{
1162	struct nfs_inode *nfsi = NFS_I(ino);
1163	struct pnfs_layout_hdr *lo;
1164	u32 current_seqid;
1165
1166	spin_lock(&ino->i_lock);
1167	lo = nfsi->layout;
1168	current_seqid = be32_to_cpu(lo->plh_stateid.seqid);
1169
1170	/* Since close does not return a layout stateid for use as
1171	 * a barrier, we choose the worst-case barrier.
1172	 */
1173	*barrier = current_seqid + atomic_read(&lo->plh_outstanding);
1174	spin_unlock(&ino->i_lock);
1175}
1176
1177bool pnfs_wait_on_layoutreturn(struct inode *ino, struct rpc_task *task)
1178{
1179	struct nfs_inode *nfsi = NFS_I(ino);
1180        struct pnfs_layout_hdr *lo;
1181        bool sleep = false;
1182
1183	/* we might not have grabbed lo reference. so need to check under
1184	 * i_lock */
1185        spin_lock(&ino->i_lock);
1186        lo = nfsi->layout;
1187        if (lo && test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
 
1188                sleep = true;
 
1189        spin_unlock(&ino->i_lock);
1190
1191        if (sleep)
1192                rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
1193
1194        return sleep;
1195}
1196
1197/*
1198 * Compare two layout segments for sorting into layout cache.
1199 * We want to preferentially return RW over RO layouts, so ensure those
1200 * are seen first.
1201 */
1202static s64
1203pnfs_lseg_range_cmp(const struct pnfs_layout_range *l1,
1204	   const struct pnfs_layout_range *l2)
1205{
1206	s64 d;
1207
1208	/* high offset > low offset */
1209	d = l1->offset - l2->offset;
1210	if (d)
1211		return d;
1212
1213	/* short length > long length */
1214	d = l2->length - l1->length;
1215	if (d)
1216		return d;
1217
1218	/* read > read/write */
1219	return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
1220}
1221
1222static bool
1223pnfs_lseg_range_is_after(const struct pnfs_layout_range *l1,
1224		const struct pnfs_layout_range *l2)
1225{
1226	return pnfs_lseg_range_cmp(l1, l2) > 0;
1227}
1228
1229static bool
1230pnfs_lseg_no_merge(struct pnfs_layout_segment *lseg,
1231		struct pnfs_layout_segment *old)
1232{
1233	return false;
1234}
1235
1236void
1237pnfs_generic_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1238		   struct pnfs_layout_segment *lseg,
1239		   bool (*is_after)(const struct pnfs_layout_range *,
1240			   const struct pnfs_layout_range *),
1241		   bool (*do_merge)(struct pnfs_layout_segment *,
1242			   struct pnfs_layout_segment *),
1243		   struct list_head *free_me)
1244{
1245	struct pnfs_layout_segment *lp, *tmp;
1246
1247	dprintk("%s:Begin\n", __func__);
1248
1249	list_for_each_entry_safe(lp, tmp, &lo->plh_segs, pls_list) {
1250		if (test_bit(NFS_LSEG_VALID, &lp->pls_flags) == 0)
1251			continue;
1252		if (do_merge(lseg, lp)) {
1253			mark_lseg_invalid(lp, free_me);
1254			continue;
1255		}
1256		if (is_after(&lseg->pls_range, &lp->pls_range))
1257			continue;
1258		list_add_tail(&lseg->pls_list, &lp->pls_list);
1259		dprintk("%s: inserted lseg %p "
1260			"iomode %d offset %llu length %llu before "
1261			"lp %p iomode %d offset %llu length %llu\n",
1262			__func__, lseg, lseg->pls_range.iomode,
1263			lseg->pls_range.offset, lseg->pls_range.length,
1264			lp, lp->pls_range.iomode, lp->pls_range.offset,
1265			lp->pls_range.length);
1266		goto out;
1267	}
1268	list_add_tail(&lseg->pls_list, &lo->plh_segs);
1269	dprintk("%s: inserted lseg %p "
1270		"iomode %d offset %llu length %llu at tail\n",
1271		__func__, lseg, lseg->pls_range.iomode,
1272		lseg->pls_range.offset, lseg->pls_range.length);
1273out:
1274	pnfs_get_layout_hdr(lo);
1275
1276	dprintk("%s:Return\n", __func__);
1277}
1278EXPORT_SYMBOL_GPL(pnfs_generic_layout_insert_lseg);
1279
1280static void
1281pnfs_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1282		   struct pnfs_layout_segment *lseg,
1283		   struct list_head *free_me)
1284{
1285	struct inode *inode = lo->plh_inode;
1286	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
1287
1288	if (ld->add_lseg != NULL)
1289		ld->add_lseg(lo, lseg, free_me);
1290	else
1291		pnfs_generic_layout_insert_lseg(lo, lseg,
1292				pnfs_lseg_range_is_after,
1293				pnfs_lseg_no_merge,
1294				free_me);
1295}
1296
1297static struct pnfs_layout_hdr *
1298alloc_init_layout_hdr(struct inode *ino,
1299		      struct nfs_open_context *ctx,
1300		      gfp_t gfp_flags)
1301{
1302	struct pnfs_layout_hdr *lo;
1303
1304	lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
1305	if (!lo)
1306		return NULL;
1307	atomic_set(&lo->plh_refcount, 1);
1308	INIT_LIST_HEAD(&lo->plh_layouts);
1309	INIT_LIST_HEAD(&lo->plh_segs);
 
1310	INIT_LIST_HEAD(&lo->plh_bulk_destroy);
1311	lo->plh_inode = ino;
1312	lo->plh_lc_cred = get_rpccred(ctx->cred);
 
1313	return lo;
1314}
1315
1316static struct pnfs_layout_hdr *
1317pnfs_find_alloc_layout(struct inode *ino,
1318		       struct nfs_open_context *ctx,
1319		       gfp_t gfp_flags)
 
 
1320{
1321	struct nfs_inode *nfsi = NFS_I(ino);
1322	struct pnfs_layout_hdr *new = NULL;
1323
1324	dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
1325
1326	if (nfsi->layout != NULL)
1327		goto out_existing;
1328	spin_unlock(&ino->i_lock);
1329	new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
1330	spin_lock(&ino->i_lock);
1331
1332	if (likely(nfsi->layout == NULL)) {	/* Won the race? */
1333		nfsi->layout = new;
1334		return new;
1335	} else if (new != NULL)
1336		pnfs_free_layout_hdr(new);
1337out_existing:
1338	pnfs_get_layout_hdr(nfsi->layout);
1339	return nfsi->layout;
1340}
1341
1342/*
1343 * iomode matching rules:
1344 * iomode	lseg	match
1345 * -----	-----	-----
1346 * ANY		READ	true
1347 * ANY		RW	true
1348 * RW		READ	false
1349 * RW		RW	true
1350 * READ		READ	true
1351 * READ		RW	true
 
 
1352 */
1353static bool
1354pnfs_lseg_range_match(const struct pnfs_layout_range *ls_range,
1355		 const struct pnfs_layout_range *range)
 
1356{
1357	struct pnfs_layout_range range1;
1358
1359	if ((range->iomode == IOMODE_RW &&
1360	     ls_range->iomode != IOMODE_RW) ||
 
 
1361	    !pnfs_lseg_range_intersecting(ls_range, range))
1362		return 0;
1363
1364	/* range1 covers only the first byte in the range */
1365	range1 = *range;
1366	range1.length = 1;
1367	return pnfs_lseg_range_contained(ls_range, &range1);
1368}
1369
1370/*
1371 * lookup range in layout
1372 */
1373static struct pnfs_layout_segment *
1374pnfs_find_lseg(struct pnfs_layout_hdr *lo,
1375		struct pnfs_layout_range *range)
 
1376{
1377	struct pnfs_layout_segment *lseg, *ret = NULL;
1378
1379	dprintk("%s:Begin\n", __func__);
1380
1381	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
1382		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
1383		    !test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags) &&
1384		    pnfs_lseg_range_match(&lseg->pls_range, range)) {
 
1385			ret = pnfs_get_lseg(lseg);
1386			break;
1387		}
1388	}
1389
1390	dprintk("%s:Return lseg %p ref %d\n",
1391		__func__, ret, ret ? atomic_read(&ret->pls_refcount) : 0);
1392	return ret;
1393}
1394
1395/*
1396 * Use mdsthreshold hints set at each OPEN to determine if I/O should go
1397 * to the MDS or over pNFS
1398 *
1399 * The nfs_inode read_io and write_io fields are cumulative counters reset
1400 * when there are no layout segments. Note that in pnfs_update_layout iomode
1401 * is set to IOMODE_READ for a READ request, and set to IOMODE_RW for a
1402 * WRITE request.
1403 *
1404 * A return of true means use MDS I/O.
1405 *
1406 * From rfc 5661:
1407 * If a file's size is smaller than the file size threshold, data accesses
1408 * SHOULD be sent to the metadata server.  If an I/O request has a length that
1409 * is below the I/O size threshold, the I/O SHOULD be sent to the metadata
1410 * server.  If both file size and I/O size are provided, the client SHOULD
1411 * reach or exceed  both thresholds before sending its read or write
1412 * requests to the data server.
1413 */
1414static bool pnfs_within_mdsthreshold(struct nfs_open_context *ctx,
1415				     struct inode *ino, int iomode)
1416{
1417	struct nfs4_threshold *t = ctx->mdsthreshold;
1418	struct nfs_inode *nfsi = NFS_I(ino);
1419	loff_t fsize = i_size_read(ino);
1420	bool size = false, size_set = false, io = false, io_set = false, ret = false;
1421
1422	if (t == NULL)
1423		return ret;
1424
1425	dprintk("%s bm=0x%x rd_sz=%llu wr_sz=%llu rd_io=%llu wr_io=%llu\n",
1426		__func__, t->bm, t->rd_sz, t->wr_sz, t->rd_io_sz, t->wr_io_sz);
1427
1428	switch (iomode) {
1429	case IOMODE_READ:
1430		if (t->bm & THRESHOLD_RD) {
1431			dprintk("%s fsize %llu\n", __func__, fsize);
1432			size_set = true;
1433			if (fsize < t->rd_sz)
1434				size = true;
1435		}
1436		if (t->bm & THRESHOLD_RD_IO) {
1437			dprintk("%s nfsi->read_io %llu\n", __func__,
1438				nfsi->read_io);
1439			io_set = true;
1440			if (nfsi->read_io < t->rd_io_sz)
1441				io = true;
1442		}
1443		break;
1444	case IOMODE_RW:
1445		if (t->bm & THRESHOLD_WR) {
1446			dprintk("%s fsize %llu\n", __func__, fsize);
1447			size_set = true;
1448			if (fsize < t->wr_sz)
1449				size = true;
1450		}
1451		if (t->bm & THRESHOLD_WR_IO) {
1452			dprintk("%s nfsi->write_io %llu\n", __func__,
1453				nfsi->write_io);
1454			io_set = true;
1455			if (nfsi->write_io < t->wr_io_sz)
1456				io = true;
1457		}
1458		break;
1459	}
1460	if (size_set && io_set) {
1461		if (size && io)
1462			ret = true;
1463	} else if (size || io)
1464		ret = true;
1465
1466	dprintk("<-- %s size %d io %d ret %d\n", __func__, size, io, ret);
1467	return ret;
1468}
1469
1470static bool pnfs_prepare_to_retry_layoutget(struct pnfs_layout_hdr *lo)
1471{
1472	/*
1473	 * send layoutcommit as it can hold up layoutreturn due to lseg
1474	 * reference
1475	 */
1476	pnfs_layoutcommit_inode(lo->plh_inode, false);
1477	return !wait_on_bit_action(&lo->plh_flags, NFS_LAYOUT_RETURN,
1478				   nfs_wait_bit_killable,
1479				   TASK_UNINTERRUPTIBLE);
1480}
1481
1482static void pnfs_clear_first_layoutget(struct pnfs_layout_hdr *lo)
1483{
1484	unsigned long *bitlock = &lo->plh_flags;
1485
1486	clear_bit_unlock(NFS_LAYOUT_FIRST_LAYOUTGET, bitlock);
1487	smp_mb__after_atomic();
1488	wake_up_bit(bitlock, NFS_LAYOUT_FIRST_LAYOUTGET);
1489}
1490
1491/*
1492 * Layout segment is retreived from the server if not cached.
1493 * The appropriate layout segment is referenced and returned to the caller.
1494 */
1495struct pnfs_layout_segment *
1496pnfs_update_layout(struct inode *ino,
1497		   struct nfs_open_context *ctx,
1498		   loff_t pos,
1499		   u64 count,
1500		   enum pnfs_iomode iomode,
 
1501		   gfp_t gfp_flags)
1502{
1503	struct pnfs_layout_range arg = {
1504		.iomode = iomode,
1505		.offset = pos,
1506		.length = count,
1507	};
1508	unsigned pg_offset;
1509	struct nfs_server *server = NFS_SERVER(ino);
1510	struct nfs_client *clp = server->nfs_client;
1511	struct pnfs_layout_hdr *lo;
1512	struct pnfs_layout_segment *lseg = NULL;
 
 
 
1513	bool first;
1514
1515	if (!pnfs_enabled_sb(NFS_SERVER(ino))) {
1516		trace_pnfs_update_layout(ino, pos, count, iomode, NULL,
1517				 PNFS_UPDATE_LAYOUT_NO_PNFS);
1518		goto out;
1519	}
1520
1521	if (iomode == IOMODE_READ && i_size_read(ino) == 0) {
1522		trace_pnfs_update_layout(ino, pos, count, iomode, NULL,
1523				 PNFS_UPDATE_LAYOUT_RD_ZEROLEN);
1524		goto out;
1525	}
1526
1527	if (pnfs_within_mdsthreshold(ctx, ino, iomode)) {
1528		trace_pnfs_update_layout(ino, pos, count, iomode, NULL,
1529				 PNFS_UPDATE_LAYOUT_MDSTHRESH);
1530		goto out;
1531	}
1532
1533lookup_again:
 
1534	first = false;
1535	spin_lock(&ino->i_lock);
1536	lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
1537	if (lo == NULL) {
1538		spin_unlock(&ino->i_lock);
1539		trace_pnfs_update_layout(ino, pos, count, iomode, NULL,
1540				 PNFS_UPDATE_LAYOUT_NOMEM);
1541		goto out;
1542	}
1543
1544	/* Do we even need to bother with this? */
1545	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1546		trace_pnfs_update_layout(ino, pos, count, iomode, lo,
1547				 PNFS_UPDATE_LAYOUT_BULK_RECALL);
1548		dprintk("%s matches recall, use MDS\n", __func__);
1549		goto out_unlock;
1550	}
1551
1552	/* if LAYOUTGET already failed once we don't try again */
1553	if (pnfs_layout_io_test_failed(lo, iomode)) {
1554		trace_pnfs_update_layout(ino, pos, count, iomode, lo,
1555				 PNFS_UPDATE_LAYOUT_IO_TEST_FAIL);
1556		goto out_unlock;
1557	}
1558
1559	first = list_empty(&lo->plh_segs);
1560	if (first) {
1561		/* The first layoutget for the file. Need to serialize per
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1562		 * RFC 5661 Errata 3208.
1563		 */
1564		if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET,
1565				     &lo->plh_flags)) {
1566			spin_unlock(&ino->i_lock);
1567			wait_on_bit(&lo->plh_flags, NFS_LAYOUT_FIRST_LAYOUTGET,
1568				    TASK_UNINTERRUPTIBLE);
1569			pnfs_put_layout_hdr(lo);
 
1570			goto lookup_again;
1571		}
1572	} else {
1573		/* Check to see if the layout for the given range
1574		 * already exists
1575		 */
1576		lseg = pnfs_find_lseg(lo, &arg);
1577		if (lseg) {
1578			trace_pnfs_update_layout(ino, pos, count, iomode, lo,
1579					PNFS_UPDATE_LAYOUT_FOUND_CACHED);
1580			goto out_unlock;
1581		}
 
 
1582	}
1583
1584	/*
1585	 * Because we free lsegs before sending LAYOUTRETURN, we need to wait
1586	 * for LAYOUTRETURN even if first is true.
1587	 */
1588	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
1589		spin_unlock(&ino->i_lock);
1590		dprintk("%s wait for layoutreturn\n", __func__);
1591		if (pnfs_prepare_to_retry_layoutget(lo)) {
1592			if (first)
1593				pnfs_clear_first_layoutget(lo);
1594			pnfs_put_layout_hdr(lo);
1595			dprintk("%s retrying\n", __func__);
 
 
1596			goto lookup_again;
1597		}
1598		trace_pnfs_update_layout(ino, pos, count, iomode, lo,
1599				PNFS_UPDATE_LAYOUT_RETURN);
1600		goto out_put_layout_hdr;
1601	}
1602
1603	if (pnfs_layoutgets_blocked(lo)) {
1604		trace_pnfs_update_layout(ino, pos, count, iomode, lo,
1605				PNFS_UPDATE_LAYOUT_BLOCKED);
1606		goto out_unlock;
1607	}
1608	atomic_inc(&lo->plh_outstanding);
1609	spin_unlock(&ino->i_lock);
1610
1611	if (list_empty(&lo->plh_layouts)) {
1612		/* The lo must be on the clp list if there is any
1613		 * chance of a CB_LAYOUTRECALL(FILE) coming in.
1614		 */
1615		spin_lock(&clp->cl_lock);
1616		if (list_empty(&lo->plh_layouts))
1617			list_add_tail(&lo->plh_layouts, &server->layouts);
1618		spin_unlock(&clp->cl_lock);
1619	}
1620
1621	pg_offset = arg.offset & ~PAGE_MASK;
1622	if (pg_offset) {
1623		arg.offset -= pg_offset;
1624		arg.length += pg_offset;
1625	}
1626	if (arg.length != NFS4_MAX_UINT64)
1627		arg.length = PAGE_ALIGN(arg.length);
1628
1629	lseg = send_layoutget(lo, ctx, &arg, gfp_flags);
 
 
1630	atomic_dec(&lo->plh_outstanding);
1631	trace_pnfs_update_layout(ino, pos, count, iomode, lo,
1632				 PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1633out_put_layout_hdr:
1634	if (first)
1635		pnfs_clear_first_layoutget(lo);
1636	pnfs_put_layout_hdr(lo);
1637out:
1638	dprintk("%s: inode %s/%llu pNFS layout segment %s for "
1639			"(%s, offset: %llu, length: %llu)\n",
1640			__func__, ino->i_sb->s_id,
1641			(unsigned long long)NFS_FILEID(ino),
1642			IS_ERR_OR_NULL(lseg) ? "not found" : "found",
1643			iomode==IOMODE_RW ?  "read/write" : "read-only",
1644			(unsigned long long)pos,
1645			(unsigned long long)count);
1646	return lseg;
1647out_unlock:
1648	spin_unlock(&ino->i_lock);
1649	goto out_put_layout_hdr;
1650}
1651EXPORT_SYMBOL_GPL(pnfs_update_layout);
1652
1653static bool
1654pnfs_sanity_check_layout_range(struct pnfs_layout_range *range)
1655{
1656	switch (range->iomode) {
1657	case IOMODE_READ:
1658	case IOMODE_RW:
1659		break;
1660	default:
1661		return false;
1662	}
1663	if (range->offset == NFS4_MAX_UINT64)
1664		return false;
1665	if (range->length == 0)
1666		return false;
1667	if (range->length != NFS4_MAX_UINT64 &&
1668	    range->length > NFS4_MAX_UINT64 - range->offset)
1669		return false;
1670	return true;
1671}
1672
1673struct pnfs_layout_segment *
1674pnfs_layout_process(struct nfs4_layoutget *lgp)
1675{
1676	struct pnfs_layout_hdr *lo = NFS_I(lgp->args.inode)->layout;
1677	struct nfs4_layoutget_res *res = &lgp->res;
1678	struct pnfs_layout_segment *lseg;
1679	struct inode *ino = lo->plh_inode;
1680	LIST_HEAD(free_me);
1681	int status = -EINVAL;
1682
1683	if (!pnfs_sanity_check_layout_range(&res->range))
1684		goto out;
1685
1686	/* Inject layout blob into I/O device driver */
1687	lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
1688	if (!lseg || IS_ERR(lseg)) {
1689		if (!lseg)
1690			status = -ENOMEM;
1691		else
1692			status = PTR_ERR(lseg);
1693		dprintk("%s: Could not allocate layout: error %d\n",
1694		       __func__, status);
1695		goto out;
1696	}
1697
1698	init_lseg(lo, lseg);
1699	lseg->pls_range = res->range;
1700
1701	spin_lock(&ino->i_lock);
1702	if (pnfs_layoutgets_blocked(lo)) {
1703		dprintk("%s forget reply due to state\n", __func__);
1704		goto out_forget_reply;
1705	}
1706
1707	if (nfs4_stateid_match_other(&lo->plh_stateid, &res->stateid)) {
 
 
 
1708		/* existing state ID, make sure the sequence number matches. */
1709		if (pnfs_layout_stateid_blocked(lo, &res->stateid)) {
1710			dprintk("%s forget reply due to sequence\n", __func__);
1711			status = -EAGAIN;
1712			goto out_forget_reply;
1713		}
1714		pnfs_set_layout_stateid(lo, &res->stateid, false);
1715	} else {
1716		/*
1717		 * We got an entirely new state ID.  Mark all segments for the
1718		 * inode invalid, and don't bother validating the stateid
1719		 * sequence number.
1720		 */
1721		pnfs_mark_matching_lsegs_invalid(lo, &free_me, NULL);
1722
1723		nfs4_stateid_copy(&lo->plh_stateid, &res->stateid);
1724		lo->plh_barrier = be32_to_cpu(res->stateid.seqid);
1725	}
1726
1727	clear_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
1728
1729	pnfs_get_lseg(lseg);
1730	pnfs_layout_insert_lseg(lo, lseg, &free_me);
1731
 
1732	if (res->return_on_close)
1733		set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
1734
1735	spin_unlock(&ino->i_lock);
1736	pnfs_free_lseg_list(&free_me);
1737	return lseg;
1738out:
1739	return ERR_PTR(status);
1740
1741out_forget_reply:
1742	spin_unlock(&ino->i_lock);
1743	lseg->pls_layout = lo;
1744	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
1745	goto out;
1746}
1747
1748static void
1749pnfs_set_plh_return_iomode(struct pnfs_layout_hdr *lo, enum pnfs_iomode iomode)
1750{
1751	if (lo->plh_return_iomode == iomode)
1752		return;
1753	if (lo->plh_return_iomode != 0)
1754		iomode = IOMODE_ANY;
1755	lo->plh_return_iomode = iomode;
1756	set_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
1757}
1758
1759/**
1760 * pnfs_mark_matching_lsegs_return - Free or return matching layout segments
1761 * @lo: pointer to layout header
1762 * @tmp_list: list header to be used with pnfs_free_lseg_list()
1763 * @return_range: describe layout segment ranges to be returned
1764 *
1765 * This function is mainly intended for use by layoutrecall. It attempts
1766 * to free the layout segment immediately, or else to mark it for return
1767 * as soon as its reference count drops to zero.
1768 */
1769int
1770pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
1771				struct list_head *tmp_list,
1772				const struct pnfs_layout_range *return_range)
 
1773{
1774	struct pnfs_layout_segment *lseg, *next;
1775	int remaining = 0;
1776
1777	dprintk("%s:Begin lo %p\n", __func__, lo);
1778
1779	if (list_empty(&lo->plh_segs))
1780		return 0;
1781
1782	assert_spin_locked(&lo->plh_inode->i_lock);
1783
1784	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
1785		if (should_free_lseg(&lseg->pls_range, return_range)) {
1786			dprintk("%s: marking lseg %p iomode %d "
1787				"offset %llu length %llu\n", __func__,
1788				lseg, lseg->pls_range.iomode,
1789				lseg->pls_range.offset,
1790				lseg->pls_range.length);
1791			if (mark_lseg_invalid(lseg, tmp_list))
1792				continue;
1793			remaining++;
1794			set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
1795			pnfs_set_plh_return_iomode(lo, return_range->iomode);
1796		}
 
 
 
 
1797	return remaining;
1798}
1799
1800void pnfs_error_mark_layout_for_return(struct inode *inode,
1801				       struct pnfs_layout_segment *lseg)
1802{
1803	struct pnfs_layout_hdr *lo = NFS_I(inode)->layout;
1804	struct pnfs_layout_range range = {
1805		.iomode = lseg->pls_range.iomode,
1806		.offset = 0,
1807		.length = NFS4_MAX_UINT64,
1808	};
1809	LIST_HEAD(free_me);
1810	bool return_now = false;
1811
1812	spin_lock(&inode->i_lock);
1813	pnfs_set_plh_return_iomode(lo, range.iomode);
 
 
 
 
1814	/*
1815	 * mark all matching lsegs so that we are sure to have no live
1816	 * segments at hand when sending layoutreturn. See pnfs_put_lseg()
1817	 * for how it works.
1818	 */
1819	if (!pnfs_mark_matching_lsegs_return(lo, &free_me, &range)) {
1820		nfs4_stateid stateid;
1821		enum pnfs_iomode iomode = lo->plh_return_iomode;
1822
1823		nfs4_stateid_copy(&stateid, &lo->plh_stateid);
1824		return_now = pnfs_prepare_layoutreturn(lo);
1825		spin_unlock(&inode->i_lock);
1826		if (return_now)
1827			pnfs_send_layoutreturn(lo, &stateid, iomode, false);
1828	} else {
1829		spin_unlock(&inode->i_lock);
1830		nfs_commit_inode(inode, 0);
1831	}
1832	pnfs_free_lseg_list(&free_me);
1833}
1834EXPORT_SYMBOL_GPL(pnfs_error_mark_layout_for_return);
1835
1836void
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1837pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
1838{
1839	u64 rd_size = req->wb_bytes;
1840
 
 
1841	if (pgio->pg_lseg == NULL) {
1842		if (pgio->pg_dreq == NULL)
1843			rd_size = i_size_read(pgio->pg_inode) - req_offset(req);
1844		else
1845			rd_size = nfs_dreq_bytes_left(pgio->pg_dreq);
1846
1847		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
1848						   req->wb_context,
1849						   req_offset(req),
1850						   rd_size,
1851						   IOMODE_READ,
 
1852						   GFP_KERNEL);
1853		if (IS_ERR(pgio->pg_lseg)) {
1854			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
1855			pgio->pg_lseg = NULL;
1856			return;
1857		}
1858	}
1859	/* If no lseg, fall back to read through mds */
1860	if (pgio->pg_lseg == NULL)
1861		nfs_pageio_reset_read_mds(pgio);
1862
1863}
1864EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);
1865
1866void
1867pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
1868			   struct nfs_page *req, u64 wb_size)
1869{
 
 
1870	if (pgio->pg_lseg == NULL) {
1871		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
1872						   req->wb_context,
1873						   req_offset(req),
1874						   wb_size,
1875						   IOMODE_RW,
 
1876						   GFP_NOFS);
1877		if (IS_ERR(pgio->pg_lseg)) {
1878			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
1879			pgio->pg_lseg = NULL;
1880			return;
1881		}
1882	}
1883	/* If no lseg, fall back to write through mds */
1884	if (pgio->pg_lseg == NULL)
1885		nfs_pageio_reset_write_mds(pgio);
1886}
1887EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
1888
1889void
1890pnfs_generic_pg_cleanup(struct nfs_pageio_descriptor *desc)
1891{
1892	if (desc->pg_lseg) {
1893		pnfs_put_lseg(desc->pg_lseg);
1894		desc->pg_lseg = NULL;
1895	}
1896}
1897EXPORT_SYMBOL_GPL(pnfs_generic_pg_cleanup);
1898
1899/*
1900 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
1901 * of bytes (maximum @req->wb_bytes) that can be coalesced.
1902 */
1903size_t
1904pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio,
1905		     struct nfs_page *prev, struct nfs_page *req)
1906{
1907	unsigned int size;
1908	u64 seg_end, req_start, seg_left;
1909
1910	size = nfs_generic_pg_test(pgio, prev, req);
1911	if (!size)
1912		return 0;
1913
1914	/*
1915	 * 'size' contains the number of bytes left in the current page (up
1916	 * to the original size asked for in @req->wb_bytes).
1917	 *
1918	 * Calculate how many bytes are left in the layout segment
1919	 * and if there are less bytes than 'size', return that instead.
1920	 *
1921	 * Please also note that 'end_offset' is actually the offset of the
1922	 * first byte that lies outside the pnfs_layout_range. FIXME?
1923	 *
1924	 */
1925	if (pgio->pg_lseg) {
1926		seg_end = end_offset(pgio->pg_lseg->pls_range.offset,
1927				     pgio->pg_lseg->pls_range.length);
1928		req_start = req_offset(req);
1929		WARN_ON_ONCE(req_start >= seg_end);
1930		/* start of request is past the last byte of this segment */
1931		if (req_start >= seg_end) {
1932			/* reference the new lseg */
1933			if (pgio->pg_ops->pg_cleanup)
1934				pgio->pg_ops->pg_cleanup(pgio);
1935			if (pgio->pg_ops->pg_init)
1936				pgio->pg_ops->pg_init(pgio, req);
1937			return 0;
1938		}
1939
1940		/* adjust 'size' iff there are fewer bytes left in the
1941		 * segment than what nfs_generic_pg_test returned */
1942		seg_left = seg_end - req_start;
1943		if (seg_left < size)
1944			size = (unsigned int)seg_left;
1945	}
1946
1947	return size;
1948}
1949EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
1950
1951int pnfs_write_done_resend_to_mds(struct nfs_pgio_header *hdr)
1952{
1953	struct nfs_pageio_descriptor pgio;
1954
1955	/* Resend all requests through the MDS */
1956	nfs_pageio_init_write(&pgio, hdr->inode, FLUSH_STABLE, true,
1957			      hdr->completion_ops);
1958	set_bit(NFS_CONTEXT_RESEND_WRITES, &hdr->args.context->flags);
1959	return nfs_pageio_resend(&pgio, hdr);
1960}
1961EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
1962
1963static void pnfs_ld_handle_write_error(struct nfs_pgio_header *hdr)
1964{
1965
1966	dprintk("pnfs write error = %d\n", hdr->pnfs_error);
1967	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
1968	    PNFS_LAYOUTRET_ON_ERROR) {
1969		pnfs_return_layout(hdr->inode);
1970	}
1971	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
1972		hdr->task.tk_status = pnfs_write_done_resend_to_mds(hdr);
1973}
1974
1975/*
1976 * Called by non rpc-based layout drivers
1977 */
1978void pnfs_ld_write_done(struct nfs_pgio_header *hdr)
1979{
1980	if (likely(!hdr->pnfs_error)) {
1981		pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
1982				hdr->mds_offset + hdr->res.count);
1983		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
1984	}
1985	trace_nfs4_pnfs_write(hdr, hdr->pnfs_error);
1986	if (unlikely(hdr->pnfs_error))
1987		pnfs_ld_handle_write_error(hdr);
1988	hdr->mds_ops->rpc_release(hdr);
1989}
1990EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
1991
1992static void
1993pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
1994		struct nfs_pgio_header *hdr)
1995{
1996	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
1997
1998	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1999		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
2000		nfs_pageio_reset_write_mds(desc);
2001		mirror->pg_recoalesce = 1;
2002	}
2003	nfs_pgio_data_destroy(hdr);
2004	hdr->release(hdr);
2005}
2006
2007static enum pnfs_try_status
2008pnfs_try_to_write_data(struct nfs_pgio_header *hdr,
2009			const struct rpc_call_ops *call_ops,
2010			struct pnfs_layout_segment *lseg,
2011			int how)
2012{
2013	struct inode *inode = hdr->inode;
2014	enum pnfs_try_status trypnfs;
2015	struct nfs_server *nfss = NFS_SERVER(inode);
2016
2017	hdr->mds_ops = call_ops;
2018
2019	dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
2020		inode->i_ino, hdr->args.count, hdr->args.offset, how);
2021	trypnfs = nfss->pnfs_curr_ld->write_pagelist(hdr, how);
2022	if (trypnfs != PNFS_NOT_ATTEMPTED)
2023		nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
2024	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
2025	return trypnfs;
2026}
2027
2028static void
2029pnfs_do_write(struct nfs_pageio_descriptor *desc,
2030	      struct nfs_pgio_header *hdr, int how)
2031{
2032	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
2033	struct pnfs_layout_segment *lseg = desc->pg_lseg;
2034	enum pnfs_try_status trypnfs;
2035
2036	trypnfs = pnfs_try_to_write_data(hdr, call_ops, lseg, how);
2037	if (trypnfs == PNFS_NOT_ATTEMPTED)
 
2038		pnfs_write_through_mds(desc, hdr);
 
 
 
 
 
 
 
 
 
 
 
2039}
2040
2041static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
2042{
2043	pnfs_put_lseg(hdr->lseg);
2044	nfs_pgio_header_free(hdr);
2045}
2046
2047int
2048pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
2049{
2050	struct nfs_pgio_header *hdr;
2051	int ret;
2052
2053	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
2054	if (!hdr) {
2055		desc->pg_error = -ENOMEM;
2056		return desc->pg_error;
2057	}
2058	nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
2059
2060	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
2061	ret = nfs_generic_pgio(desc, hdr);
2062	if (!ret)
2063		pnfs_do_write(desc, hdr, desc->pg_ioflags);
2064
2065	return ret;
2066}
2067EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
2068
2069int pnfs_read_done_resend_to_mds(struct nfs_pgio_header *hdr)
2070{
2071	struct nfs_pageio_descriptor pgio;
2072
2073	/* Resend all requests through the MDS */
2074	nfs_pageio_init_read(&pgio, hdr->inode, true, hdr->completion_ops);
2075	return nfs_pageio_resend(&pgio, hdr);
2076}
2077EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
2078
2079static void pnfs_ld_handle_read_error(struct nfs_pgio_header *hdr)
2080{
2081	dprintk("pnfs read error = %d\n", hdr->pnfs_error);
2082	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2083	    PNFS_LAYOUTRET_ON_ERROR) {
2084		pnfs_return_layout(hdr->inode);
2085	}
2086	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2087		hdr->task.tk_status = pnfs_read_done_resend_to_mds(hdr);
2088}
2089
2090/*
2091 * Called by non rpc-based layout drivers
2092 */
2093void pnfs_ld_read_done(struct nfs_pgio_header *hdr)
2094{
2095	if (likely(!hdr->pnfs_error)) {
2096		__nfs4_read_done_cb(hdr);
2097		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
2098	}
2099	trace_nfs4_pnfs_read(hdr, hdr->pnfs_error);
2100	if (unlikely(hdr->pnfs_error))
2101		pnfs_ld_handle_read_error(hdr);
2102	hdr->mds_ops->rpc_release(hdr);
2103}
2104EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
2105
2106static void
2107pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
2108		struct nfs_pgio_header *hdr)
2109{
2110	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2111
2112	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2113		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
2114		nfs_pageio_reset_read_mds(desc);
2115		mirror->pg_recoalesce = 1;
2116	}
2117	nfs_pgio_data_destroy(hdr);
2118	hdr->release(hdr);
2119}
2120
2121/*
2122 * Call the appropriate parallel I/O subsystem read function.
2123 */
2124static enum pnfs_try_status
2125pnfs_try_to_read_data(struct nfs_pgio_header *hdr,
2126		       const struct rpc_call_ops *call_ops,
2127		       struct pnfs_layout_segment *lseg)
2128{
2129	struct inode *inode = hdr->inode;
2130	struct nfs_server *nfss = NFS_SERVER(inode);
2131	enum pnfs_try_status trypnfs;
2132
2133	hdr->mds_ops = call_ops;
2134
2135	dprintk("%s: Reading ino:%lu %u@%llu\n",
2136		__func__, inode->i_ino, hdr->args.count, hdr->args.offset);
2137
2138	trypnfs = nfss->pnfs_curr_ld->read_pagelist(hdr);
2139	if (trypnfs != PNFS_NOT_ATTEMPTED)
2140		nfs_inc_stats(inode, NFSIOS_PNFS_READ);
2141	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
2142	return trypnfs;
2143}
2144
2145/* Resend all requests through pnfs. */
2146int pnfs_read_resend_pnfs(struct nfs_pgio_header *hdr)
2147{
2148	struct nfs_pageio_descriptor pgio;
2149
2150	nfs_pageio_init_read(&pgio, hdr->inode, false, hdr->completion_ops);
2151	return nfs_pageio_resend(&pgio, hdr);
 
 
 
 
 
 
 
2152}
2153EXPORT_SYMBOL_GPL(pnfs_read_resend_pnfs);
2154
2155static void
2156pnfs_do_read(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr)
2157{
2158	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
2159	struct pnfs_layout_segment *lseg = desc->pg_lseg;
2160	enum pnfs_try_status trypnfs;
2161	int err = 0;
2162
2163	trypnfs = pnfs_try_to_read_data(hdr, call_ops, lseg);
2164	if (trypnfs == PNFS_TRY_AGAIN)
2165		err = pnfs_read_resend_pnfs(hdr);
2166	if (trypnfs == PNFS_NOT_ATTEMPTED || err)
2167		pnfs_read_through_mds(desc, hdr);
 
 
 
 
 
 
 
 
 
 
 
2168}
2169
2170static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
2171{
2172	pnfs_put_lseg(hdr->lseg);
2173	nfs_pgio_header_free(hdr);
2174}
2175
2176int
2177pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
2178{
2179	struct nfs_pgio_header *hdr;
2180	int ret;
2181
2182	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
2183	if (!hdr) {
2184		desc->pg_error = -ENOMEM;
2185		return desc->pg_error;
2186	}
2187	nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
2188	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
2189	ret = nfs_generic_pgio(desc, hdr);
2190	if (!ret)
2191		pnfs_do_read(desc, hdr);
2192	return ret;
2193}
2194EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
2195
2196static void pnfs_clear_layoutcommitting(struct inode *inode)
2197{
2198	unsigned long *bitlock = &NFS_I(inode)->flags;
2199
2200	clear_bit_unlock(NFS_INO_LAYOUTCOMMITTING, bitlock);
2201	smp_mb__after_atomic();
2202	wake_up_bit(bitlock, NFS_INO_LAYOUTCOMMITTING);
2203}
2204
2205/*
2206 * There can be multiple RW segments.
2207 */
2208static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
2209{
2210	struct pnfs_layout_segment *lseg;
2211
2212	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
2213		if (lseg->pls_range.iomode == IOMODE_RW &&
2214		    test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
2215			list_add(&lseg->pls_lc_list, listp);
2216	}
2217}
2218
2219static void pnfs_list_write_lseg_done(struct inode *inode, struct list_head *listp)
2220{
2221	struct pnfs_layout_segment *lseg, *tmp;
2222
2223	/* Matched by references in pnfs_set_layoutcommit */
2224	list_for_each_entry_safe(lseg, tmp, listp, pls_lc_list) {
2225		list_del_init(&lseg->pls_lc_list);
2226		pnfs_put_lseg(lseg);
2227	}
2228
2229	pnfs_clear_layoutcommitting(inode);
2230}
2231
2232void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
2233{
2234	pnfs_layout_io_set_failed(lseg->pls_layout, lseg->pls_range.iomode);
2235}
2236EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
2237
2238void
2239pnfs_set_layoutcommit(struct inode *inode, struct pnfs_layout_segment *lseg,
2240		loff_t end_pos)
2241{
2242	struct nfs_inode *nfsi = NFS_I(inode);
2243	bool mark_as_dirty = false;
2244
2245	spin_lock(&inode->i_lock);
2246	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
2247		nfsi->layout->plh_lwb = end_pos;
2248		mark_as_dirty = true;
2249		dprintk("%s: Set layoutcommit for inode %lu ",
2250			__func__, inode->i_ino);
2251	} else if (end_pos > nfsi->layout->plh_lwb)
2252		nfsi->layout->plh_lwb = end_pos;
2253	if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags)) {
2254		/* references matched in nfs4_layoutcommit_release */
2255		pnfs_get_lseg(lseg);
2256	}
2257	spin_unlock(&inode->i_lock);
2258	dprintk("%s: lseg %p end_pos %llu\n",
2259		__func__, lseg, nfsi->layout->plh_lwb);
2260
2261	/* if pnfs_layoutcommit_inode() runs between inode locks, the next one
2262	 * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */
2263	if (mark_as_dirty)
2264		mark_inode_dirty_sync(inode);
2265}
2266EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
2267
2268void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data)
2269{
2270	struct nfs_server *nfss = NFS_SERVER(data->args.inode);
2271
2272	if (nfss->pnfs_curr_ld->cleanup_layoutcommit)
2273		nfss->pnfs_curr_ld->cleanup_layoutcommit(data);
2274	pnfs_list_write_lseg_done(data->args.inode, &data->lseg_list);
2275}
2276
2277/*
2278 * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
2279 * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
2280 * data to disk to allow the server to recover the data if it crashes.
2281 * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
2282 * is off, and a COMMIT is sent to a data server, or
2283 * if WRITEs to a data server return NFS_DATA_SYNC.
2284 */
2285int
2286pnfs_layoutcommit_inode(struct inode *inode, bool sync)
2287{
2288	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
2289	struct nfs4_layoutcommit_data *data;
2290	struct nfs_inode *nfsi = NFS_I(inode);
2291	loff_t end_pos;
2292	int status;
2293
2294	if (!pnfs_layoutcommit_outstanding(inode))
2295		return 0;
2296
2297	dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
2298
2299	status = -EAGAIN;
2300	if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
2301		if (!sync)
2302			goto out;
2303		status = wait_on_bit_lock_action(&nfsi->flags,
2304				NFS_INO_LAYOUTCOMMITTING,
2305				nfs_wait_bit_killable,
2306				TASK_KILLABLE);
2307		if (status)
2308			goto out;
2309	}
2310
2311	status = -ENOMEM;
2312	/* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
2313	data = kzalloc(sizeof(*data), GFP_NOFS);
2314	if (!data)
2315		goto clear_layoutcommitting;
2316
2317	status = 0;
2318	spin_lock(&inode->i_lock);
2319	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
2320		goto out_unlock;
2321
2322	INIT_LIST_HEAD(&data->lseg_list);
2323	pnfs_list_write_lseg(inode, &data->lseg_list);
2324
2325	end_pos = nfsi->layout->plh_lwb;
2326
2327	nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
2328	spin_unlock(&inode->i_lock);
2329
2330	data->args.inode = inode;
2331	data->cred = get_rpccred(nfsi->layout->plh_lc_cred);
2332	nfs_fattr_init(&data->fattr);
2333	data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
2334	data->res.fattr = &data->fattr;
2335	data->args.lastbytewritten = end_pos - 1;
 
 
 
2336	data->res.server = NFS_SERVER(inode);
2337
2338	if (ld->prepare_layoutcommit) {
2339		status = ld->prepare_layoutcommit(&data->args);
2340		if (status) {
2341			put_rpccred(data->cred);
2342			spin_lock(&inode->i_lock);
2343			set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags);
2344			if (end_pos > nfsi->layout->plh_lwb)
2345				nfsi->layout->plh_lwb = end_pos;
2346			goto out_unlock;
2347		}
2348	}
2349
2350
2351	status = nfs4_proc_layoutcommit(data, sync);
2352out:
2353	if (status)
2354		mark_inode_dirty_sync(inode);
2355	dprintk("<-- %s status %d\n", __func__, status);
2356	return status;
2357out_unlock:
2358	spin_unlock(&inode->i_lock);
2359	kfree(data);
2360clear_layoutcommitting:
2361	pnfs_clear_layoutcommitting(inode);
2362	goto out;
2363}
2364EXPORT_SYMBOL_GPL(pnfs_layoutcommit_inode);
2365
2366int
2367pnfs_generic_sync(struct inode *inode, bool datasync)
2368{
2369	return pnfs_layoutcommit_inode(inode, true);
2370}
2371EXPORT_SYMBOL_GPL(pnfs_generic_sync);
2372
2373struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
2374{
2375	struct nfs4_threshold *thp;
2376
2377	thp = kzalloc(sizeof(*thp), GFP_NOFS);
2378	if (!thp) {
2379		dprintk("%s mdsthreshold allocation failed\n", __func__);
2380		return NULL;
2381	}
2382	return thp;
2383}
2384
2385#if IS_ENABLED(CONFIG_NFS_V4_2)
2386int
2387pnfs_report_layoutstat(struct inode *inode, gfp_t gfp_flags)
2388{
2389	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
2390	struct nfs_server *server = NFS_SERVER(inode);
2391	struct nfs_inode *nfsi = NFS_I(inode);
2392	struct nfs42_layoutstat_data *data;
2393	struct pnfs_layout_hdr *hdr;
2394	int status = 0;
2395
2396	if (!pnfs_enabled_sb(server) || !ld->prepare_layoutstats)
2397		goto out;
2398
2399	if (!nfs_server_capable(inode, NFS_CAP_LAYOUTSTATS))
2400		goto out;
2401
2402	if (test_and_set_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags))
2403		goto out;
2404
2405	spin_lock(&inode->i_lock);
2406	if (!NFS_I(inode)->layout) {
2407		spin_unlock(&inode->i_lock);
2408		goto out;
2409	}
2410	hdr = NFS_I(inode)->layout;
2411	pnfs_get_layout_hdr(hdr);
2412	spin_unlock(&inode->i_lock);
2413
2414	data = kzalloc(sizeof(*data), gfp_flags);
2415	if (!data) {
2416		status = -ENOMEM;
2417		goto out_put;
2418	}
2419
2420	data->args.fh = NFS_FH(inode);
2421	data->args.inode = inode;
2422	nfs4_stateid_copy(&data->args.stateid, &hdr->plh_stateid);
2423	status = ld->prepare_layoutstats(&data->args);
2424	if (status)
2425		goto out_free;
2426
2427	status = nfs42_proc_layoutstats_generic(NFS_SERVER(inode), data);
2428
2429out:
2430	dprintk("%s returns %d\n", __func__, status);
2431	return status;
2432
2433out_free:
2434	kfree(data);
2435out_put:
2436	pnfs_put_layout_hdr(hdr);
 
2437	smp_mb__before_atomic();
2438	clear_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags);
2439	smp_mb__after_atomic();
2440	goto out;
2441}
2442EXPORT_SYMBOL_GPL(pnfs_report_layoutstat);
2443#endif
2444
2445unsigned int layoutstats_timer;
2446module_param(layoutstats_timer, uint, 0644);
2447EXPORT_SYMBOL_GPL(layoutstats_timer);