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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);
v6.8
   1/*
   2 *  pNFS functions to call and manage layout drivers.
   3 *
   4 *  Copyright (c) 2002 [year of first publication]
   5 *  The Regents of the University of Michigan
   6 *  All Rights Reserved
   7 *
   8 *  Dean Hildebrand <dhildebz@umich.edu>
   9 *
  10 *  Permission is granted to use, copy, create derivative works, and
  11 *  redistribute this software and such derivative works for any purpose,
  12 *  so long as the name of the University of Michigan is not used in
  13 *  any advertising or publicity pertaining to the use or distribution
  14 *  of this software without specific, written prior authorization. If
  15 *  the above copyright notice or any other identification of the
  16 *  University of Michigan is included in any copy of any portion of
  17 *  this software, then the disclaimer below must also be included.
  18 *
  19 *  This software is provided as is, without representation or warranty
  20 *  of any kind either express or implied, including without limitation
  21 *  the implied warranties of merchantability, fitness for a particular
  22 *  purpose, or noninfringement.  The Regents of the University of
  23 *  Michigan shall not be liable for any damages, including special,
  24 *  indirect, incidental, or consequential damages, with respect to any
  25 *  claim arising out of or in connection with the use of the software,
  26 *  even if it has been or is hereafter advised of the possibility of
  27 *  such damages.
  28 */
  29
  30#include <linux/nfs_fs.h>
  31#include <linux/nfs_page.h>
  32#include <linux/module.h>
  33#include <linux/sort.h>
  34#include "internal.h"
  35#include "pnfs.h"
  36#include "iostat.h"
  37#include "nfs4trace.h"
  38#include "delegation.h"
  39#include "nfs42.h"
  40#include "nfs4_fs.h"
  41
  42#define NFSDBG_FACILITY		NFSDBG_PNFS
  43#define PNFS_LAYOUTGET_RETRY_TIMEOUT (120*HZ)
  44
  45/* Locking:
  46 *
  47 * pnfs_spinlock:
  48 *      protects pnfs_modules_tbl.
  49 */
  50static DEFINE_SPINLOCK(pnfs_spinlock);
  51
  52/*
  53 * pnfs_modules_tbl holds all pnfs modules
  54 */
  55static LIST_HEAD(pnfs_modules_tbl);
  56
  57static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo);
  58static void pnfs_free_returned_lsegs(struct pnfs_layout_hdr *lo,
  59		struct list_head *free_me,
  60		const struct pnfs_layout_range *range,
  61		u32 seq);
  62static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
  63		                struct list_head *tmp_list);
  64
  65/* Return the registered pnfs layout driver module matching given id */
  66static struct pnfs_layoutdriver_type *
  67find_pnfs_driver_locked(u32 id)
  68{
  69	struct pnfs_layoutdriver_type *local;
  70
  71	list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid)
  72		if (local->id == id)
  73			goto out;
  74	local = NULL;
  75out:
  76	dprintk("%s: Searching for id %u, found %p\n", __func__, id, local);
  77	return local;
  78}
  79
  80static struct pnfs_layoutdriver_type *
  81find_pnfs_driver(u32 id)
  82{
  83	struct pnfs_layoutdriver_type *local;
  84
  85	spin_lock(&pnfs_spinlock);
  86	local = find_pnfs_driver_locked(id);
  87	if (local != NULL && !try_module_get(local->owner)) {
  88		dprintk("%s: Could not grab reference on module\n", __func__);
  89		local = NULL;
  90	}
  91	spin_unlock(&pnfs_spinlock);
  92	return local;
  93}
  94
  95const struct pnfs_layoutdriver_type *pnfs_find_layoutdriver(u32 id)
  96{
  97	return find_pnfs_driver(id);
  98}
  99
 100void pnfs_put_layoutdriver(const struct pnfs_layoutdriver_type *ld)
 101{
 102	if (ld)
 103		module_put(ld->owner);
 104}
 105
 106void
 107unset_pnfs_layoutdriver(struct nfs_server *nfss)
 108{
 109	if (nfss->pnfs_curr_ld) {
 110		if (nfss->pnfs_curr_ld->clear_layoutdriver)
 111			nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
 112		/* Decrement the MDS count. Purge the deviceid cache if zero */
 113		if (atomic_dec_and_test(&nfss->nfs_client->cl_mds_count))
 114			nfs4_deviceid_purge_client(nfss->nfs_client);
 115		module_put(nfss->pnfs_curr_ld->owner);
 116	}
 117	nfss->pnfs_curr_ld = NULL;
 118}
 119
 120/*
 121 * When the server sends a list of layout types, we choose one in the order
 122 * given in the list below.
 123 *
 124 * FIXME: should this list be configurable in some fashion? module param?
 125 * 	  mount option? something else?
 126 */
 127static const u32 ld_prefs[] = {
 128	LAYOUT_SCSI,
 129	LAYOUT_BLOCK_VOLUME,
 130	LAYOUT_OSD2_OBJECTS,
 131	LAYOUT_FLEX_FILES,
 132	LAYOUT_NFSV4_1_FILES,
 133	0
 134};
 135
 136static int
 137ld_cmp(const void *e1, const void *e2)
 138{
 139	u32 ld1 = *((u32 *)e1);
 140	u32 ld2 = *((u32 *)e2);
 141	int i;
 142
 143	for (i = 0; ld_prefs[i] != 0; i++) {
 144		if (ld1 == ld_prefs[i])
 145			return -1;
 146
 147		if (ld2 == ld_prefs[i])
 148			return 1;
 149	}
 150	return 0;
 151}
 152
 153/*
 154 * Try to set the server's pnfs module to the pnfs layout type specified by id.
 155 * Currently only one pNFS layout driver per filesystem is supported.
 156 *
 157 * @ids array of layout types supported by MDS.
 158 */
 159void
 160set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
 161		      struct nfs_fsinfo *fsinfo)
 162{
 163	struct pnfs_layoutdriver_type *ld_type = NULL;
 164	u32 id;
 165	int i;
 166
 167	if (fsinfo->nlayouttypes == 0)
 168		goto out_no_driver;
 169	if (!(server->nfs_client->cl_exchange_flags &
 170		 (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
 171		printk(KERN_ERR "NFS: %s: cl_exchange_flags 0x%x\n",
 172			__func__, server->nfs_client->cl_exchange_flags);
 173		goto out_no_driver;
 174	}
 175
 176	sort(fsinfo->layouttype, fsinfo->nlayouttypes,
 177		sizeof(*fsinfo->layouttype), ld_cmp, NULL);
 178
 179	for (i = 0; i < fsinfo->nlayouttypes; i++) {
 180		id = fsinfo->layouttype[i];
 181		ld_type = find_pnfs_driver(id);
 182		if (!ld_type) {
 183			request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX,
 184					id);
 185			ld_type = find_pnfs_driver(id);
 186		}
 187		if (ld_type)
 188			break;
 189	}
 190
 191	if (!ld_type) {
 192		dprintk("%s: No pNFS module found!\n", __func__);
 193		goto out_no_driver;
 194	}
 195
 196	server->pnfs_curr_ld = ld_type;
 197	if (ld_type->set_layoutdriver
 198	    && ld_type->set_layoutdriver(server, mntfh)) {
 199		printk(KERN_ERR "NFS: %s: Error initializing pNFS layout "
 200			"driver %u.\n", __func__, id);
 201		module_put(ld_type->owner);
 202		goto out_no_driver;
 203	}
 204	/* Bump the MDS count */
 205	atomic_inc(&server->nfs_client->cl_mds_count);
 206
 207	dprintk("%s: pNFS module for %u set\n", __func__, id);
 208	return;
 209
 210out_no_driver:
 211	dprintk("%s: Using NFSv4 I/O\n", __func__);
 212	server->pnfs_curr_ld = NULL;
 213}
 214
 215int
 216pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 217{
 218	int status = -EINVAL;
 219	struct pnfs_layoutdriver_type *tmp;
 220
 221	if (ld_type->id == 0) {
 222		printk(KERN_ERR "NFS: %s id 0 is reserved\n", __func__);
 223		return status;
 224	}
 225	if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
 226		printk(KERN_ERR "NFS: %s Layout driver must provide "
 227		       "alloc_lseg and free_lseg.\n", __func__);
 228		return status;
 229	}
 230
 231	spin_lock(&pnfs_spinlock);
 232	tmp = find_pnfs_driver_locked(ld_type->id);
 233	if (!tmp) {
 234		list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
 235		status = 0;
 236		dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
 237			ld_type->name);
 238	} else {
 239		printk(KERN_ERR "NFS: %s Module with id %d already loaded!\n",
 240			__func__, ld_type->id);
 241	}
 242	spin_unlock(&pnfs_spinlock);
 243
 244	return status;
 245}
 246EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);
 247
 248void
 249pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 250{
 251	dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
 252	spin_lock(&pnfs_spinlock);
 253	list_del(&ld_type->pnfs_tblid);
 254	spin_unlock(&pnfs_spinlock);
 255}
 256EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
 257
 258/*
 259 * pNFS client layout cache
 260 */
 261
 262/* Need to hold i_lock if caller does not already hold reference */
 263void
 264pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo)
 265{
 266	refcount_inc(&lo->plh_refcount);
 267}
 268
 269static struct pnfs_layout_hdr *
 270pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags)
 271{
 272	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
 273	return ld->alloc_layout_hdr(ino, gfp_flags);
 274}
 275
 276static void
 277pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
 278{
 279	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
 280	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
 281
 282	if (test_and_clear_bit(NFS_LAYOUT_HASHED, &lo->plh_flags)) {
 283		struct nfs_client *clp = server->nfs_client;
 284
 285		spin_lock(&clp->cl_lock);
 286		list_del_rcu(&lo->plh_layouts);
 287		spin_unlock(&clp->cl_lock);
 288	}
 289	put_cred(lo->plh_lc_cred);
 290	return ld->free_layout_hdr(lo);
 291}
 292
 293static void
 294pnfs_detach_layout_hdr(struct pnfs_layout_hdr *lo)
 295{
 296	struct nfs_inode *nfsi = NFS_I(lo->plh_inode);
 297	dprintk("%s: freeing layout cache %p\n", __func__, lo);
 298	nfsi->layout = NULL;
 299	/* Reset MDS Threshold I/O counters */
 300	nfsi->write_io = 0;
 301	nfsi->read_io = 0;
 302}
 303
 304void
 305pnfs_put_layout_hdr(struct pnfs_layout_hdr *lo)
 306{
 307	struct inode *inode;
 308	unsigned long i_state;
 309
 310	if (!lo)
 311		return;
 312	inode = lo->plh_inode;
 313	pnfs_layoutreturn_before_put_layout_hdr(lo);
 314
 315	if (refcount_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
 316		if (!list_empty(&lo->plh_segs))
 317			WARN_ONCE(1, "NFS: BUG unfreed layout segments.\n");
 318		pnfs_detach_layout_hdr(lo);
 319		i_state = inode->i_state;
 320		spin_unlock(&inode->i_lock);
 321		pnfs_free_layout_hdr(lo);
 322		/* Notify pnfs_destroy_layout_final() that we're done */
 323		if (i_state & (I_FREEING | I_CLEAR))
 324			wake_up_var(lo);
 325	}
 326}
 327
 328static struct inode *
 329pnfs_grab_inode_layout_hdr(struct pnfs_layout_hdr *lo)
 330{
 331	struct inode *inode = igrab(lo->plh_inode);
 332	if (inode)
 333		return inode;
 334	set_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags);
 335	return NULL;
 336}
 337
 338/*
 339 * Compare 2 layout stateid sequence ids, to see which is newer,
 340 * taking into account wraparound issues.
 341 */
 342static bool pnfs_seqid_is_newer(u32 s1, u32 s2)
 343{
 344	return (s32)(s1 - s2) > 0;
 345}
 346
 347static void pnfs_barrier_update(struct pnfs_layout_hdr *lo, u32 newseq)
 348{
 349	if (pnfs_seqid_is_newer(newseq, lo->plh_barrier) || !lo->plh_barrier)
 350		lo->plh_barrier = newseq;
 351}
 352
 353static void
 354pnfs_set_plh_return_info(struct pnfs_layout_hdr *lo, enum pnfs_iomode iomode,
 355			 u32 seq)
 356{
 357	if (lo->plh_return_iomode != 0 && lo->plh_return_iomode != iomode)
 358		iomode = IOMODE_ANY;
 359	lo->plh_return_iomode = iomode;
 360	set_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 361	/*
 362	 * We must set lo->plh_return_seq to avoid livelocks with
 363	 * pnfs_layout_need_return()
 364	 */
 365	if (seq == 0)
 366		seq = be32_to_cpu(lo->plh_stateid.seqid);
 367	if (!lo->plh_return_seq || pnfs_seqid_is_newer(seq, lo->plh_return_seq))
 368		lo->plh_return_seq = seq;
 369	pnfs_barrier_update(lo, seq);
 370}
 371
 372static void
 373pnfs_clear_layoutreturn_info(struct pnfs_layout_hdr *lo)
 374{
 375	struct pnfs_layout_segment *lseg;
 376	lo->plh_return_iomode = 0;
 377	lo->plh_return_seq = 0;
 378	clear_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 379	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
 380		if (!test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
 381			continue;
 382		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
 383	}
 384}
 385
 386static void pnfs_clear_layoutreturn_waitbit(struct pnfs_layout_hdr *lo)
 387{
 388	clear_bit_unlock(NFS_LAYOUT_RETURN, &lo->plh_flags);
 389	clear_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags);
 390	smp_mb__after_atomic();
 391	wake_up_bit(&lo->plh_flags, NFS_LAYOUT_RETURN);
 392	rpc_wake_up(&NFS_SERVER(lo->plh_inode)->roc_rpcwaitq);
 393}
 394
 395static void
 396pnfs_clear_lseg_state(struct pnfs_layout_segment *lseg,
 397		struct list_head *free_me)
 398{
 399	clear_bit(NFS_LSEG_ROC, &lseg->pls_flags);
 400	clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
 401	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags))
 402		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 403	if (test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
 404		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 405}
 406
 407/*
 408 * Update the seqid of a layout stateid after receiving
 409 * NFS4ERR_OLD_STATEID
 410 */
 411bool nfs4_layout_refresh_old_stateid(nfs4_stateid *dst,
 412		struct pnfs_layout_range *dst_range,
 413		struct inode *inode)
 414{
 415	struct pnfs_layout_hdr *lo;
 416	struct pnfs_layout_range range = {
 417		.iomode = IOMODE_ANY,
 418		.offset = 0,
 419		.length = NFS4_MAX_UINT64,
 420	};
 421	bool ret = false;
 422	LIST_HEAD(head);
 423	int err;
 424
 425	spin_lock(&inode->i_lock);
 426	lo = NFS_I(inode)->layout;
 427	if (lo &&  pnfs_layout_is_valid(lo) &&
 428	    nfs4_stateid_match_other(dst, &lo->plh_stateid)) {
 429		/* Is our call using the most recent seqid? If so, bump it */
 430		if (!nfs4_stateid_is_newer(&lo->plh_stateid, dst)) {
 431			nfs4_stateid_seqid_inc(dst);
 432			ret = true;
 433			goto out;
 434		}
 435		/* Try to update the seqid to the most recent */
 436		err = pnfs_mark_matching_lsegs_return(lo, &head, &range, 0);
 437		if (err != -EBUSY) {
 438			dst->seqid = lo->plh_stateid.seqid;
 439			*dst_range = range;
 440			ret = true;
 441		}
 442	}
 443out:
 444	spin_unlock(&inode->i_lock);
 445	pnfs_free_lseg_list(&head);
 446	return ret;
 447}
 448
 449/*
 450 * Mark a pnfs_layout_hdr and all associated layout segments as invalid
 451 *
 452 * In order to continue using the pnfs_layout_hdr, a full recovery
 453 * is required.
 454 * Note that caller must hold inode->i_lock.
 455 */
 456int
 457pnfs_mark_layout_stateid_invalid(struct pnfs_layout_hdr *lo,
 458		struct list_head *lseg_list)
 459{
 460	struct pnfs_layout_range range = {
 461		.iomode = IOMODE_ANY,
 462		.offset = 0,
 463		.length = NFS4_MAX_UINT64,
 464	};
 465	struct pnfs_layout_segment *lseg, *next;
 466
 467	set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 468	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 469		pnfs_clear_lseg_state(lseg, lseg_list);
 470	pnfs_clear_layoutreturn_info(lo);
 471	pnfs_free_returned_lsegs(lo, lseg_list, &range, 0);
 472	set_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags);
 473	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags) &&
 474	    !test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
 475		pnfs_clear_layoutreturn_waitbit(lo);
 476	return !list_empty(&lo->plh_segs);
 477}
 478
 479static int
 480pnfs_iomode_to_fail_bit(u32 iomode)
 481{
 482	return iomode == IOMODE_RW ?
 483		NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 484}
 485
 486static void
 487pnfs_layout_set_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 488{
 489	lo->plh_retry_timestamp = jiffies;
 490	if (!test_and_set_bit(fail_bit, &lo->plh_flags))
 491		refcount_inc(&lo->plh_refcount);
 492}
 493
 494static void
 495pnfs_layout_clear_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 496{
 497	if (test_and_clear_bit(fail_bit, &lo->plh_flags))
 498		refcount_dec(&lo->plh_refcount);
 499}
 500
 501static void
 502pnfs_layout_io_set_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 503{
 504	struct inode *inode = lo->plh_inode;
 505	struct pnfs_layout_range range = {
 506		.iomode = iomode,
 507		.offset = 0,
 508		.length = NFS4_MAX_UINT64,
 509	};
 510	LIST_HEAD(head);
 511
 512	spin_lock(&inode->i_lock);
 513	pnfs_layout_set_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
 514	pnfs_mark_matching_lsegs_return(lo, &head, &range, 0);
 515	spin_unlock(&inode->i_lock);
 516	pnfs_free_lseg_list(&head);
 517	dprintk("%s Setting layout IOMODE_%s fail bit\n", __func__,
 518			iomode == IOMODE_RW ?  "RW" : "READ");
 519}
 520
 521static bool
 522pnfs_layout_io_test_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 523{
 524	unsigned long start, end;
 525	int fail_bit = pnfs_iomode_to_fail_bit(iomode);
 526
 527	if (test_bit(fail_bit, &lo->plh_flags) == 0)
 528		return false;
 529	end = jiffies;
 530	start = end - PNFS_LAYOUTGET_RETRY_TIMEOUT;
 531	if (!time_in_range(lo->plh_retry_timestamp, start, end)) {
 532		/* It is time to retry the failed layoutgets */
 533		pnfs_layout_clear_fail_bit(lo, fail_bit);
 534		return false;
 535	}
 536	return true;
 537}
 538
 539static void
 540pnfs_init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg,
 541		const struct pnfs_layout_range *range,
 542		const nfs4_stateid *stateid)
 543{
 544	INIT_LIST_HEAD(&lseg->pls_list);
 545	INIT_LIST_HEAD(&lseg->pls_lc_list);
 546	INIT_LIST_HEAD(&lseg->pls_commits);
 547	refcount_set(&lseg->pls_refcount, 1);
 548	set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
 549	lseg->pls_layout = lo;
 550	lseg->pls_range = *range;
 551	lseg->pls_seq = be32_to_cpu(stateid->seqid);
 552}
 553
 554static void pnfs_free_lseg(struct pnfs_layout_segment *lseg)
 555{
 556	if (lseg != NULL) {
 557		struct inode *inode = lseg->pls_layout->plh_inode;
 558		NFS_SERVER(inode)->pnfs_curr_ld->free_lseg(lseg);
 559	}
 560}
 561
 562static void
 563pnfs_layout_remove_lseg(struct pnfs_layout_hdr *lo,
 564		struct pnfs_layout_segment *lseg)
 565{
 
 
 566	WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 567	list_del_init(&lseg->pls_list);
 568	/* Matched by pnfs_get_layout_hdr in pnfs_layout_insert_lseg */
 569	refcount_dec(&lo->plh_refcount);
 570	if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
 571		return;
 572	if (list_empty(&lo->plh_segs) &&
 573	    !test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) &&
 574	    !test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
 575		if (atomic_read(&lo->plh_outstanding) == 0)
 576			set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 577		clear_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 578	}
 579}
 580
 581static bool
 582pnfs_cache_lseg_for_layoutreturn(struct pnfs_layout_hdr *lo,
 583		struct pnfs_layout_segment *lseg)
 584{
 585	if (test_and_clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags) &&
 586	    pnfs_layout_is_valid(lo)) {
 587		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
 588		list_move_tail(&lseg->pls_list, &lo->plh_return_segs);
 589		return true;
 590	}
 591	return false;
 592}
 593
 594void
 595pnfs_put_lseg(struct pnfs_layout_segment *lseg)
 596{
 597	struct pnfs_layout_hdr *lo;
 598	struct inode *inode;
 599
 600	if (!lseg)
 601		return;
 602
 603	dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
 604		refcount_read(&lseg->pls_refcount),
 605		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 606
 607	lo = lseg->pls_layout;
 608	inode = lo->plh_inode;
 609
 610	if (refcount_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
 
 
 
 
 611		pnfs_get_layout_hdr(lo);
 612		pnfs_layout_remove_lseg(lo, lseg);
 613		if (pnfs_cache_lseg_for_layoutreturn(lo, lseg))
 614			lseg = NULL;
 615		spin_unlock(&inode->i_lock);
 616		pnfs_free_lseg(lseg);
 617		pnfs_put_layout_hdr(lo);
 618	}
 619}
 620EXPORT_SYMBOL_GPL(pnfs_put_lseg);
 621
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 622/*
 623 * is l2 fully contained in l1?
 624 *   start1                             end1
 625 *   [----------------------------------)
 626 *           start2           end2
 627 *           [----------------)
 628 */
 629static bool
 630pnfs_lseg_range_contained(const struct pnfs_layout_range *l1,
 631		 const struct pnfs_layout_range *l2)
 632{
 633	u64 start1 = l1->offset;
 634	u64 end1 = pnfs_end_offset(start1, l1->length);
 635	u64 start2 = l2->offset;
 636	u64 end2 = pnfs_end_offset(start2, l2->length);
 637
 638	return (start1 <= start2) && (end1 >= end2);
 639}
 640
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 641static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
 642		struct list_head *tmp_list)
 643{
 644	if (!refcount_dec_and_test(&lseg->pls_refcount))
 645		return false;
 646	pnfs_layout_remove_lseg(lseg->pls_layout, lseg);
 647	list_add(&lseg->pls_list, tmp_list);
 648	return true;
 649}
 650
 651/* Returns 1 if lseg is removed from list, 0 otherwise */
 652static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
 653			     struct list_head *tmp_list)
 654{
 655	int rv = 0;
 656
 657	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 658		/* Remove the reference keeping the lseg in the
 659		 * list.  It will now be removed when all
 660		 * outstanding io is finished.
 661		 */
 662		dprintk("%s: lseg %p ref %d\n", __func__, lseg,
 663			refcount_read(&lseg->pls_refcount));
 664		if (pnfs_lseg_dec_and_remove_zero(lseg, tmp_list))
 665			rv = 1;
 666	}
 667	return rv;
 668}
 669
 670static bool
 671pnfs_should_free_range(const struct pnfs_layout_range *lseg_range,
 672		 const struct pnfs_layout_range *recall_range)
 673{
 674	return (recall_range->iomode == IOMODE_ANY ||
 675		lseg_range->iomode == recall_range->iomode) &&
 676	       pnfs_lseg_range_intersecting(lseg_range, recall_range);
 677}
 678
 679static bool
 680pnfs_match_lseg_recall(const struct pnfs_layout_segment *lseg,
 681		const struct pnfs_layout_range *recall_range,
 682		u32 seq)
 683{
 684	if (seq != 0 && pnfs_seqid_is_newer(lseg->pls_seq, seq))
 685		return false;
 686	if (recall_range == NULL)
 687		return true;
 688	return pnfs_should_free_range(&lseg->pls_range, recall_range);
 689}
 690
 691/**
 692 * pnfs_mark_matching_lsegs_invalid - tear down lsegs or mark them for later
 693 * @lo: layout header containing the lsegs
 694 * @tmp_list: list head where doomed lsegs should go
 695 * @recall_range: optional recall range argument to match (may be NULL)
 696 * @seq: only invalidate lsegs obtained prior to this sequence (may be 0)
 697 *
 698 * Walk the list of lsegs in the layout header, and tear down any that should
 699 * be destroyed. If "recall_range" is specified then the segment must match
 700 * that range. If "seq" is non-zero, then only match segments that were handed
 701 * out at or before that sequence.
 702 *
 703 * Returns number of matching invalid lsegs remaining in list after scanning
 704 * it and purging them.
 705 */
 706int
 707pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 708			    struct list_head *tmp_list,
 709			    const struct pnfs_layout_range *recall_range,
 710			    u32 seq)
 711{
 712	struct pnfs_layout_segment *lseg, *next;
 713	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
 714	int remaining = 0;
 715
 716	dprintk("%s:Begin lo %p\n", __func__, lo);
 717
 718	if (list_empty(&lo->plh_segs))
 719		return 0;
 720	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 721		if (pnfs_match_lseg_recall(lseg, recall_range, seq)) {
 722			dprintk("%s: freeing lseg %p iomode %d seq %u "
 
 723				"offset %llu length %llu\n", __func__,
 724				lseg, lseg->pls_range.iomode, lseg->pls_seq,
 725				lseg->pls_range.offset, lseg->pls_range.length);
 726			if (mark_lseg_invalid(lseg, tmp_list))
 727				continue;
 728			remaining++;
 729			pnfs_lseg_cancel_io(server, lseg);
 730		}
 731	dprintk("%s:Return %i\n", __func__, remaining);
 732	return remaining;
 733}
 734
 735static void
 736pnfs_free_returned_lsegs(struct pnfs_layout_hdr *lo,
 737		struct list_head *free_me,
 738		const struct pnfs_layout_range *range,
 739		u32 seq)
 740{
 741	struct pnfs_layout_segment *lseg, *next;
 742
 743	list_for_each_entry_safe(lseg, next, &lo->plh_return_segs, pls_list) {
 744		if (pnfs_match_lseg_recall(lseg, range, seq))
 745			list_move_tail(&lseg->pls_list, free_me);
 746	}
 747}
 748
 749/* note free_me must contain lsegs from a single layout_hdr */
 750void
 751pnfs_free_lseg_list(struct list_head *free_me)
 752{
 753	struct pnfs_layout_segment *lseg, *tmp;
 754
 755	if (list_empty(free_me))
 756		return;
 757
 758	list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
 759		list_del(&lseg->pls_list);
 760		pnfs_free_lseg(lseg);
 761	}
 762}
 763
 764static struct pnfs_layout_hdr *__pnfs_destroy_layout(struct nfs_inode *nfsi)
 
 765{
 766	struct pnfs_layout_hdr *lo;
 767	LIST_HEAD(tmp_list);
 768
 769	spin_lock(&nfsi->vfs_inode.i_lock);
 770	lo = nfsi->layout;
 771	if (lo) {
 772		pnfs_get_layout_hdr(lo);
 773		pnfs_mark_layout_stateid_invalid(lo, &tmp_list);
 774		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RO_FAILED);
 775		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RW_FAILED);
 776		spin_unlock(&nfsi->vfs_inode.i_lock);
 777		pnfs_free_lseg_list(&tmp_list);
 778		nfs_commit_inode(&nfsi->vfs_inode, 0);
 779		pnfs_put_layout_hdr(lo);
 780	} else
 781		spin_unlock(&nfsi->vfs_inode.i_lock);
 782	return lo;
 783}
 784
 785void pnfs_destroy_layout(struct nfs_inode *nfsi)
 786{
 787	__pnfs_destroy_layout(nfsi);
 788}
 789EXPORT_SYMBOL_GPL(pnfs_destroy_layout);
 790
 791static bool pnfs_layout_removed(struct nfs_inode *nfsi,
 792				struct pnfs_layout_hdr *lo)
 793{
 794	bool ret;
 795
 796	spin_lock(&nfsi->vfs_inode.i_lock);
 797	ret = nfsi->layout != lo;
 798	spin_unlock(&nfsi->vfs_inode.i_lock);
 799	return ret;
 800}
 801
 802void pnfs_destroy_layout_final(struct nfs_inode *nfsi)
 803{
 804	struct pnfs_layout_hdr *lo = __pnfs_destroy_layout(nfsi);
 805
 806	if (lo)
 807		wait_var_event(lo, pnfs_layout_removed(nfsi, lo));
 808}
 809
 810static bool
 811pnfs_layout_add_bulk_destroy_list(struct inode *inode,
 812		struct list_head *layout_list)
 813{
 814	struct pnfs_layout_hdr *lo;
 815	bool ret = false;
 816
 817	spin_lock(&inode->i_lock);
 818	lo = NFS_I(inode)->layout;
 819	if (lo != NULL && list_empty(&lo->plh_bulk_destroy)) {
 820		pnfs_get_layout_hdr(lo);
 821		list_add(&lo->plh_bulk_destroy, layout_list);
 822		ret = true;
 823	}
 824	spin_unlock(&inode->i_lock);
 825	return ret;
 826}
 827
 828/* Caller must hold rcu_read_lock and clp->cl_lock */
 829static int
 830pnfs_layout_bulk_destroy_byserver_locked(struct nfs_client *clp,
 831		struct nfs_server *server,
 832		struct list_head *layout_list)
 833	__must_hold(&clp->cl_lock)
 834	__must_hold(RCU)
 835{
 836	struct pnfs_layout_hdr *lo, *next;
 837	struct inode *inode;
 838
 839	list_for_each_entry_safe(lo, next, &server->layouts, plh_layouts) {
 840		if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags) ||
 841		    test_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags) ||
 842		    !list_empty(&lo->plh_bulk_destroy))
 843			continue;
 844		/* If the sb is being destroyed, just bail */
 845		if (!nfs_sb_active(server->super))
 846			break;
 847		inode = pnfs_grab_inode_layout_hdr(lo);
 848		if (inode != NULL) {
 849			if (test_and_clear_bit(NFS_LAYOUT_HASHED, &lo->plh_flags))
 850				list_del_rcu(&lo->plh_layouts);
 851			if (pnfs_layout_add_bulk_destroy_list(inode,
 852						layout_list))
 853				continue;
 854			rcu_read_unlock();
 855			spin_unlock(&clp->cl_lock);
 856			iput(inode);
 857		} else {
 858			rcu_read_unlock();
 859			spin_unlock(&clp->cl_lock);
 860		}
 861		nfs_sb_deactive(server->super);
 862		spin_lock(&clp->cl_lock);
 863		rcu_read_lock();
 864		return -EAGAIN;
 865	}
 866	return 0;
 867}
 868
 869static int
 870pnfs_layout_free_bulk_destroy_list(struct list_head *layout_list,
 871		bool is_bulk_recall)
 872{
 873	struct pnfs_layout_hdr *lo;
 874	struct inode *inode;
 875	LIST_HEAD(lseg_list);
 876	int ret = 0;
 877
 878	while (!list_empty(layout_list)) {
 879		lo = list_entry(layout_list->next, struct pnfs_layout_hdr,
 880				plh_bulk_destroy);
 881		dprintk("%s freeing layout for inode %lu\n", __func__,
 882			lo->plh_inode->i_ino);
 883		inode = lo->plh_inode;
 884
 885		pnfs_layoutcommit_inode(inode, false);
 886
 887		spin_lock(&inode->i_lock);
 888		list_del_init(&lo->plh_bulk_destroy);
 889		if (pnfs_mark_layout_stateid_invalid(lo, &lseg_list)) {
 890			if (is_bulk_recall)
 891				set_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 892			ret = -EAGAIN;
 893		}
 894		spin_unlock(&inode->i_lock);
 895		pnfs_free_lseg_list(&lseg_list);
 896		/* Free all lsegs that are attached to commit buckets */
 897		nfs_commit_inode(inode, 0);
 898		pnfs_put_layout_hdr(lo);
 899		nfs_iput_and_deactive(inode);
 900	}
 901	return ret;
 902}
 903
 904int
 905pnfs_destroy_layouts_byfsid(struct nfs_client *clp,
 906		struct nfs_fsid *fsid,
 907		bool is_recall)
 908{
 909	struct nfs_server *server;
 910	LIST_HEAD(layout_list);
 911
 912	spin_lock(&clp->cl_lock);
 913	rcu_read_lock();
 914restart:
 915	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 916		if (memcmp(&server->fsid, fsid, sizeof(*fsid)) != 0)
 917			continue;
 918		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 919				server,
 920				&layout_list) != 0)
 921			goto restart;
 922	}
 923	rcu_read_unlock();
 924	spin_unlock(&clp->cl_lock);
 925
 926	if (list_empty(&layout_list))
 927		return 0;
 928	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 929}
 930
 931int
 932pnfs_destroy_layouts_byclid(struct nfs_client *clp,
 933		bool is_recall)
 934{
 935	struct nfs_server *server;
 936	LIST_HEAD(layout_list);
 937
 938	spin_lock(&clp->cl_lock);
 939	rcu_read_lock();
 940restart:
 941	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 942		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 943					server,
 944					&layout_list) != 0)
 945			goto restart;
 946	}
 947	rcu_read_unlock();
 948	spin_unlock(&clp->cl_lock);
 949
 950	if (list_empty(&layout_list))
 951		return 0;
 952	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 953}
 954
 955/*
 956 * Called by the state manager to remove all layouts established under an
 957 * expired lease.
 958 */
 959void
 960pnfs_destroy_all_layouts(struct nfs_client *clp)
 961{
 962	nfs4_deviceid_mark_client_invalid(clp);
 963	nfs4_deviceid_purge_client(clp);
 964
 965	pnfs_destroy_layouts_byclid(clp, false);
 966}
 967
 968static void
 969pnfs_set_layout_cred(struct pnfs_layout_hdr *lo, const struct cred *cred)
 
 
 
 970{
 971	const struct cred *old;
 972
 973	if (cred && cred_fscmp(lo->plh_lc_cred, cred) != 0) {
 974		old = xchg(&lo->plh_lc_cred, get_cred(cred));
 975		put_cred(old);
 976	}
 977}
 978
 979/* update lo->plh_stateid with new if is more recent */
 980void
 981pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
 982			const struct cred *cred, bool update_barrier)
 983{
 984	u32 oldseq = be32_to_cpu(lo->plh_stateid.seqid);
 985	u32 newseq = be32_to_cpu(new->seqid);
 986
 987	if (!pnfs_layout_is_valid(lo)) {
 988		pnfs_set_layout_cred(lo, cred);
 
 989		nfs4_stateid_copy(&lo->plh_stateid, new);
 990		lo->plh_barrier = newseq;
 991		pnfs_clear_layoutreturn_info(lo);
 992		clear_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 993		return;
 994	}
 995
 996	if (pnfs_seqid_is_newer(newseq, oldseq))
 997		nfs4_stateid_copy(&lo->plh_stateid, new);
 998
 999	if (update_barrier) {
1000		pnfs_barrier_update(lo, newseq);
1001		return;
1002	}
1003	/*
1004	 * Because of wraparound, we want to keep the barrier
1005	 * "close" to the current seqids. We really only want to
1006	 * get here from a layoutget call.
1007	 */
1008	if (atomic_read(&lo->plh_outstanding) == 1)
1009		 pnfs_barrier_update(lo, be32_to_cpu(lo->plh_stateid.seqid));
1010}
1011
1012static bool
1013pnfs_layout_stateid_blocked(const struct pnfs_layout_hdr *lo,
1014		const nfs4_stateid *stateid)
1015{
1016	u32 seqid = be32_to_cpu(stateid->seqid);
1017
1018	return lo->plh_barrier && pnfs_seqid_is_newer(lo->plh_barrier, seqid);
1019}
1020
1021/* lget is set to 1 if called from inside send_layoutget call chain */
1022static bool
1023pnfs_layoutgets_blocked(const struct pnfs_layout_hdr *lo)
1024{
1025	return lo->plh_block_lgets ||
1026		test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
1027}
1028
1029static struct nfs_server *
1030pnfs_find_server(struct inode *inode, struct nfs_open_context *ctx)
 
 
1031{
1032	struct nfs_server *server;
1033
1034	if (inode) {
1035		server = NFS_SERVER(inode);
1036	} else {
1037		struct dentry *parent_dir = dget_parent(ctx->dentry);
1038		server = NFS_SERVER(parent_dir->d_inode);
1039		dput(parent_dir);
1040	}
1041	return server;
 
 
 
 
 
 
 
 
 
 
 
1042}
1043
1044static void nfs4_free_pages(struct page **pages, size_t size)
1045{
1046	int i;
1047
1048	if (!pages)
1049		return;
1050
1051	for (i = 0; i < size; i++) {
1052		if (!pages[i])
1053			break;
1054		__free_page(pages[i]);
1055	}
1056	kfree(pages);
1057}
1058
1059static struct page **nfs4_alloc_pages(size_t size, gfp_t gfp_flags)
1060{
1061	struct page **pages;
1062	int i;
1063
1064	pages = kmalloc_array(size, sizeof(struct page *), gfp_flags);
1065	if (!pages) {
1066		dprintk("%s: can't alloc array of %zu pages\n", __func__, size);
1067		return NULL;
1068	}
1069
1070	for (i = 0; i < size; i++) {
1071		pages[i] = alloc_page(gfp_flags);
1072		if (!pages[i]) {
1073			dprintk("%s: failed to allocate page\n", __func__);
1074			nfs4_free_pages(pages, i);
1075			return NULL;
1076		}
1077	}
1078
1079	return pages;
1080}
1081
1082static struct nfs4_layoutget *
1083pnfs_alloc_init_layoutget_args(struct inode *ino,
1084	   struct nfs_open_context *ctx,
1085	   const nfs4_stateid *stateid,
1086	   const struct pnfs_layout_range *range,
1087	   gfp_t gfp_flags)
1088{
1089	struct nfs_server *server = pnfs_find_server(ino, ctx);
1090	size_t max_reply_sz = server->pnfs_curr_ld->max_layoutget_response;
1091	size_t max_pages = max_response_pages(server);
1092	struct nfs4_layoutget *lgp;
 
 
1093
1094	dprintk("--> %s\n", __func__);
1095
1096	lgp = kzalloc(sizeof(*lgp), gfp_flags);
1097	if (lgp == NULL)
1098		return NULL;
1099
1100	if (max_reply_sz) {
1101		size_t npages = (max_reply_sz + PAGE_SIZE - 1) >> PAGE_SHIFT;
1102		if (npages < max_pages)
1103			max_pages = npages;
1104	}
1105
1106	lgp->args.layout.pages = nfs4_alloc_pages(max_pages, gfp_flags);
1107	if (!lgp->args.layout.pages) {
1108		kfree(lgp);
1109		return NULL;
1110	}
1111	lgp->args.layout.pglen = max_pages * PAGE_SIZE;
1112	lgp->res.layoutp = &lgp->args.layout;
1113
1114	/* Don't confuse uninitialised result and success */
1115	lgp->res.status = -NFS4ERR_DELAY;
1116
1117	lgp->args.minlength = PAGE_SIZE;
1118	if (lgp->args.minlength > range->length)
1119		lgp->args.minlength = range->length;
1120	if (ino) {
1121		loff_t i_size = i_size_read(ino);
1122
 
 
 
1123		if (range->iomode == IOMODE_READ) {
1124			if (range->offset >= i_size)
1125				lgp->args.minlength = 0;
1126			else if (i_size - range->offset < lgp->args.minlength)
1127				lgp->args.minlength = i_size - range->offset;
1128		}
1129	}
1130	lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
1131	pnfs_copy_range(&lgp->args.range, range);
1132	lgp->args.type = server->pnfs_curr_ld->id;
1133	lgp->args.inode = ino;
1134	lgp->args.ctx = get_nfs_open_context(ctx);
1135	nfs4_stateid_copy(&lgp->args.stateid, stateid);
1136	lgp->gfp_flags = gfp_flags;
1137	lgp->cred = ctx->cred;
1138	return lgp;
1139}
1140
1141void pnfs_layoutget_free(struct nfs4_layoutget *lgp)
1142{
1143	size_t max_pages = lgp->args.layout.pglen / PAGE_SIZE;
1144
1145	nfs4_free_pages(lgp->args.layout.pages, max_pages);
1146	pnfs_put_layout_hdr(lgp->lo);
1147	put_nfs_open_context(lgp->args.ctx);
1148	kfree(lgp);
1149}
1150
1151static void pnfs_clear_layoutcommit(struct inode *inode,
1152		struct list_head *head)
1153{
1154	struct nfs_inode *nfsi = NFS_I(inode);
1155	struct pnfs_layout_segment *lseg, *tmp;
1156
1157	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
1158		return;
1159	list_for_each_entry_safe(lseg, tmp, &nfsi->layout->plh_segs, pls_list) {
1160		if (!test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
1161			continue;
1162		pnfs_lseg_dec_and_remove_zero(lseg, head);
1163	}
1164}
1165
1166void pnfs_layoutreturn_free_lsegs(struct pnfs_layout_hdr *lo,
1167		const nfs4_stateid *arg_stateid,
1168		const struct pnfs_layout_range *range,
1169		const nfs4_stateid *stateid)
1170{
1171	struct inode *inode = lo->plh_inode;
1172	LIST_HEAD(freeme);
1173
1174	spin_lock(&inode->i_lock);
1175	if (!pnfs_layout_is_valid(lo) ||
1176	    !nfs4_stateid_match_other(&lo->plh_stateid, arg_stateid))
1177		goto out_unlock;
1178	if (stateid) {
1179		u32 seq = be32_to_cpu(arg_stateid->seqid);
1180
1181		pnfs_mark_matching_lsegs_invalid(lo, &freeme, range, seq);
1182		pnfs_free_returned_lsegs(lo, &freeme, range, seq);
1183		pnfs_set_layout_stateid(lo, stateid, NULL, true);
1184	} else
1185		pnfs_mark_layout_stateid_invalid(lo, &freeme);
1186out_unlock:
1187	pnfs_clear_layoutreturn_waitbit(lo);
1188	spin_unlock(&inode->i_lock);
1189	pnfs_free_lseg_list(&freeme);
1190
1191}
1192
1193static bool
1194pnfs_prepare_layoutreturn(struct pnfs_layout_hdr *lo,
1195		nfs4_stateid *stateid,
1196		const struct cred **cred,
1197		enum pnfs_iomode *iomode)
1198{
1199	/* Serialise LAYOUTGET/LAYOUTRETURN */
1200	if (atomic_read(&lo->plh_outstanding) != 0)
1201		return false;
1202	if (test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
1203		return false;
1204	set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
1205	pnfs_get_layout_hdr(lo);
1206	nfs4_stateid_copy(stateid, &lo->plh_stateid);
1207	*cred = get_cred(lo->plh_lc_cred);
1208	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags)) {
1209		if (lo->plh_return_seq != 0)
1210			stateid->seqid = cpu_to_be32(lo->plh_return_seq);
1211		if (iomode != NULL)
1212			*iomode = lo->plh_return_iomode;
1213		pnfs_clear_layoutreturn_info(lo);
1214	} else if (iomode != NULL)
1215		*iomode = IOMODE_ANY;
1216	pnfs_barrier_update(lo, be32_to_cpu(stateid->seqid));
1217	return true;
1218}
1219
1220static void
1221pnfs_init_layoutreturn_args(struct nfs4_layoutreturn_args *args,
1222		struct pnfs_layout_hdr *lo,
1223		const nfs4_stateid *stateid,
1224		enum pnfs_iomode iomode)
1225{
1226	struct inode *inode = lo->plh_inode;
1227
1228	args->layout_type = NFS_SERVER(inode)->pnfs_curr_ld->id;
1229	args->inode = inode;
1230	args->range.iomode = iomode;
1231	args->range.offset = 0;
1232	args->range.length = NFS4_MAX_UINT64;
1233	args->layout = lo;
1234	nfs4_stateid_copy(&args->stateid, stateid);
1235}
1236
1237static int
1238pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo,
1239		       const nfs4_stateid *stateid,
1240		       const struct cred **pcred,
1241		       enum pnfs_iomode iomode,
1242		       bool sync)
1243{
1244	struct inode *ino = lo->plh_inode;
1245	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1246	struct nfs4_layoutreturn *lrp;
1247	const struct cred *cred = *pcred;
1248	int status = 0;
1249
1250	*pcred = NULL;
1251	lrp = kzalloc(sizeof(*lrp), nfs_io_gfp_mask());
1252	if (unlikely(lrp == NULL)) {
1253		status = -ENOMEM;
1254		spin_lock(&ino->i_lock);
1255		pnfs_clear_layoutreturn_waitbit(lo);
1256		spin_unlock(&ino->i_lock);
1257		put_cred(cred);
1258		pnfs_put_layout_hdr(lo);
1259		goto out;
1260	}
1261
1262	pnfs_init_layoutreturn_args(&lrp->args, lo, stateid, iomode);
1263	lrp->args.ld_private = &lrp->ld_private;
 
 
 
 
 
1264	lrp->clp = NFS_SERVER(ino)->nfs_client;
1265	lrp->cred = cred;
1266	if (ld->prepare_layoutreturn)
1267		ld->prepare_layoutreturn(&lrp->args);
1268
1269	status = nfs4_proc_layoutreturn(lrp, sync);
1270out:
1271	dprintk("<-- %s status: %d\n", __func__, status);
1272	return status;
1273}
1274
1275static bool
1276pnfs_layout_segments_returnable(struct pnfs_layout_hdr *lo,
1277				enum pnfs_iomode iomode,
1278				u32 seq)
1279{
1280	struct pnfs_layout_range recall_range = {
1281		.length = NFS4_MAX_UINT64,
1282		.iomode = iomode,
1283	};
1284	return pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs,
1285					       &recall_range, seq) != -EBUSY;
1286}
1287
1288/* Return true if layoutreturn is needed */
1289static bool
1290pnfs_layout_need_return(struct pnfs_layout_hdr *lo)
1291{
 
 
1292	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1293		return false;
1294	return pnfs_layout_segments_returnable(lo, lo->plh_return_iomode,
1295					       lo->plh_return_seq);
 
 
 
 
 
 
1296}
1297
1298static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo)
1299{
1300	struct inode *inode= lo->plh_inode;
1301
1302	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1303		return;
1304	spin_lock(&inode->i_lock);
1305	if (pnfs_layout_need_return(lo)) {
1306		const struct cred *cred;
1307		nfs4_stateid stateid;
1308		enum pnfs_iomode iomode;
1309		bool send;
1310
1311		send = pnfs_prepare_layoutreturn(lo, &stateid, &cred, &iomode);
 
 
1312		spin_unlock(&inode->i_lock);
1313		if (send) {
1314			/* Send an async layoutreturn so we dont deadlock */
1315			pnfs_send_layoutreturn(lo, &stateid, &cred, iomode, false);
1316		}
1317	} else
1318		spin_unlock(&inode->i_lock);
1319}
1320
1321/*
1322 * Initiates a LAYOUTRETURN(FILE), and removes the pnfs_layout_hdr
1323 * when the layout segment list is empty.
1324 *
1325 * Note that a pnfs_layout_hdr can exist with an empty layout segment
1326 * list when LAYOUTGET has failed, or when LAYOUTGET succeeded, but the
1327 * deviceid is marked invalid.
1328 */
1329int
1330_pnfs_return_layout(struct inode *ino)
1331{
1332	struct pnfs_layout_hdr *lo = NULL;
1333	struct nfs_inode *nfsi = NFS_I(ino);
1334	struct pnfs_layout_range range = {
1335		.iomode		= IOMODE_ANY,
1336		.offset		= 0,
1337		.length		= NFS4_MAX_UINT64,
1338	};
1339	LIST_HEAD(tmp_list);
1340	const struct cred *cred;
1341	nfs4_stateid stateid;
1342	int status = 0;
1343	bool send, valid_layout;
1344
1345	dprintk("NFS: %s for inode %lu\n", __func__, ino->i_ino);
1346
1347	spin_lock(&ino->i_lock);
1348	lo = nfsi->layout;
1349	if (!lo) {
1350		spin_unlock(&ino->i_lock);
1351		dprintk("NFS: %s no layout to return\n", __func__);
1352		goto out;
1353	}
 
1354	/* Reference matched in nfs4_layoutreturn_release */
1355	pnfs_get_layout_hdr(lo);
1356	/* Is there an outstanding layoutreturn ? */
1357	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1358		spin_unlock(&ino->i_lock);
1359		if (wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1360					TASK_UNINTERRUPTIBLE))
1361			goto out_put_layout_hdr;
1362		spin_lock(&ino->i_lock);
1363	}
1364	valid_layout = pnfs_layout_is_valid(lo);
1365	pnfs_clear_layoutcommit(ino, &tmp_list);
1366	pnfs_mark_matching_lsegs_return(lo, &tmp_list, &range, 0);
1367
1368	if (NFS_SERVER(ino)->pnfs_curr_ld->return_range)
 
 
 
 
 
1369		NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo, &range);
 
1370
1371	/* Don't send a LAYOUTRETURN if list was initially empty */
1372	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) ||
1373			!valid_layout) {
1374		spin_unlock(&ino->i_lock);
1375		dprintk("NFS: %s no layout segments to return\n", __func__);
1376		goto out_wait_layoutreturn;
1377	}
1378
1379	send = pnfs_prepare_layoutreturn(lo, &stateid, &cred, NULL);
 
1380	spin_unlock(&ino->i_lock);
 
1381	if (send)
1382		status = pnfs_send_layoutreturn(lo, &stateid, &cred, IOMODE_ANY, true);
1383out_wait_layoutreturn:
1384	wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN, TASK_UNINTERRUPTIBLE);
1385out_put_layout_hdr:
1386	pnfs_free_lseg_list(&tmp_list);
1387	pnfs_put_layout_hdr(lo);
1388out:
1389	dprintk("<-- %s status: %d\n", __func__, status);
1390	return status;
1391}
 
1392
1393int
1394pnfs_commit_and_return_layout(struct inode *inode)
1395{
1396	struct pnfs_layout_hdr *lo;
1397	int ret;
1398
1399	spin_lock(&inode->i_lock);
1400	lo = NFS_I(inode)->layout;
1401	if (lo == NULL) {
1402		spin_unlock(&inode->i_lock);
1403		return 0;
1404	}
1405	pnfs_get_layout_hdr(lo);
1406	/* Block new layoutgets and read/write to ds */
1407	lo->plh_block_lgets++;
1408	spin_unlock(&inode->i_lock);
1409	filemap_fdatawait(inode->i_mapping);
1410	ret = pnfs_layoutcommit_inode(inode, true);
1411	if (ret == 0)
1412		ret = _pnfs_return_layout(inode);
1413	spin_lock(&inode->i_lock);
1414	lo->plh_block_lgets--;
1415	spin_unlock(&inode->i_lock);
1416	pnfs_put_layout_hdr(lo);
1417	return ret;
1418}
1419
1420bool pnfs_roc(struct inode *ino,
1421		struct nfs4_layoutreturn_args *args,
1422		struct nfs4_layoutreturn_res *res,
1423		const struct cred *cred)
1424{
1425	struct nfs_inode *nfsi = NFS_I(ino);
1426	struct nfs_open_context *ctx;
1427	struct nfs4_state *state;
1428	struct pnfs_layout_hdr *lo;
1429	struct pnfs_layout_segment *lseg, *next;
1430	const struct cred *lc_cred;
1431	nfs4_stateid stateid;
1432	enum pnfs_iomode iomode = 0;
1433	bool layoutreturn = false, roc = false;
1434	bool skip_read = false;
1435
1436	if (!nfs_have_layout(ino))
1437		return false;
1438retry:
1439	rcu_read_lock();
1440	spin_lock(&ino->i_lock);
1441	lo = nfsi->layout;
1442	if (!lo || !pnfs_layout_is_valid(lo) ||
1443	    test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1444		lo = NULL;
1445		goto out_noroc;
1446	}
1447	pnfs_get_layout_hdr(lo);
1448	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1449		spin_unlock(&ino->i_lock);
1450		rcu_read_unlock();
1451		wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1452				TASK_UNINTERRUPTIBLE);
1453		pnfs_put_layout_hdr(lo);
1454		goto retry;
1455	}
1456
1457	/* no roc if we hold a delegation */
1458	if (nfs4_check_delegation(ino, FMODE_READ)) {
1459		if (nfs4_check_delegation(ino, FMODE_WRITE))
1460			goto out_noroc;
1461		skip_read = true;
1462	}
1463
1464	list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
1465		state = ctx->state;
1466		if (state == NULL)
1467			continue;
1468		/* Don't return layout if there is open file state */
1469		if (state->state & FMODE_WRITE)
1470			goto out_noroc;
1471		if (state->state & FMODE_READ)
1472			skip_read = true;
1473	}
1474
 
 
 
 
 
1475
1476	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list) {
1477		if (skip_read && lseg->pls_range.iomode == IOMODE_READ)
1478			continue;
1479		/* If we are sending layoutreturn, invalidate all valid lsegs */
1480		if (!test_and_clear_bit(NFS_LSEG_ROC, &lseg->pls_flags))
1481			continue;
1482		/*
1483		 * Note: mark lseg for return so pnfs_layout_remove_lseg
1484		 * doesn't invalidate the layout for us.
1485		 */
1486		set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
1487		if (!mark_lseg_invalid(lseg, &lo->plh_return_segs))
1488			continue;
1489		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
1490	}
1491
1492	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1493		goto out_noroc;
1494
1495	/* ROC in two conditions:
1496	 * 1. there are ROC lsegs
1497	 * 2. we don't send layoutreturn
1498	 */
1499	/* lo ref dropped in pnfs_roc_release() */
1500	layoutreturn = pnfs_prepare_layoutreturn(lo, &stateid, &lc_cred, &iomode);
1501	/* If the creds don't match, we can't compound the layoutreturn */
1502	if (!layoutreturn || cred_fscmp(cred, lc_cred) != 0)
1503		goto out_noroc;
1504
1505	roc = layoutreturn;
1506	pnfs_init_layoutreturn_args(args, lo, &stateid, iomode);
1507	res->lrs_present = 0;
1508	layoutreturn = false;
1509	put_cred(lc_cred);
1510
1511out_noroc:
1512	spin_unlock(&ino->i_lock);
1513	rcu_read_unlock();
1514	pnfs_layoutcommit_inode(ino, true);
1515	if (roc) {
1516		struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1517		if (ld->prepare_layoutreturn)
1518			ld->prepare_layoutreturn(args);
1519		pnfs_put_layout_hdr(lo);
1520		return true;
1521	}
1522	if (layoutreturn)
1523		pnfs_send_layoutreturn(lo, &stateid, &lc_cred, iomode, true);
1524	pnfs_put_layout_hdr(lo);
1525	return false;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1526}
1527
1528int pnfs_roc_done(struct rpc_task *task, struct nfs4_layoutreturn_args **argpp,
1529		  struct nfs4_layoutreturn_res **respp, int *ret)
1530{
1531	struct nfs4_layoutreturn_args *arg = *argpp;
1532	int retval = -EAGAIN;
 
1533
1534	if (!arg)
1535		return 0;
1536	/* Handle Layoutreturn errors */
1537	switch (*ret) {
1538	case 0:
1539		retval = 0;
1540		break;
1541	case -NFS4ERR_NOMATCHING_LAYOUT:
1542		/* Was there an RPC level error? If not, retry */
1543		if (task->tk_rpc_status == 0)
1544			break;
1545		/* If the call was not sent, let caller handle it */
1546		if (!RPC_WAS_SENT(task))
1547			return 0;
1548		/*
1549		 * Otherwise, assume the call succeeded and
1550		 * that we need to release the layout
1551		 */
1552		*ret = 0;
1553		(*respp)->lrs_present = 0;
1554		retval = 0;
1555		break;
1556	case -NFS4ERR_DELAY:
1557		/* Let the caller handle the retry */
1558		*ret = -NFS4ERR_NOMATCHING_LAYOUT;
1559		return 0;
1560	case -NFS4ERR_OLD_STATEID:
1561		if (!nfs4_layout_refresh_old_stateid(&arg->stateid,
1562						     &arg->range, arg->inode))
1563			break;
1564		*ret = -NFS4ERR_NOMATCHING_LAYOUT;
1565		return -EAGAIN;
1566	}
1567	*argpp = NULL;
1568	*respp = NULL;
1569	return retval;
1570}
1571
1572void pnfs_roc_release(struct nfs4_layoutreturn_args *args,
1573		struct nfs4_layoutreturn_res *res,
1574		int ret)
1575{
1576	struct pnfs_layout_hdr *lo = args->layout;
1577	struct inode *inode = args->inode;
1578	const nfs4_stateid *res_stateid = NULL;
1579	struct nfs4_xdr_opaque_data *ld_private = args->ld_private;
1580
1581	switch (ret) {
1582	case -NFS4ERR_NOMATCHING_LAYOUT:
1583		spin_lock(&inode->i_lock);
1584		if (pnfs_layout_is_valid(lo) &&
1585		    nfs4_stateid_match_other(&args->stateid, &lo->plh_stateid))
1586			pnfs_set_plh_return_info(lo, args->range.iomode, 0);
1587		pnfs_clear_layoutreturn_waitbit(lo);
1588		spin_unlock(&inode->i_lock);
1589		break;
1590	case 0:
1591		if (res->lrs_present)
1592			res_stateid = &res->stateid;
1593		fallthrough;
1594	default:
1595		pnfs_layoutreturn_free_lsegs(lo, &args->stateid, &args->range,
1596					     res_stateid);
1597	}
1598	trace_nfs4_layoutreturn_on_close(args->inode, &args->stateid, ret);
1599	if (ld_private && ld_private->ops && ld_private->ops->free)
1600		ld_private->ops->free(ld_private);
1601	pnfs_put_layout_hdr(lo);
1602}
1603
1604bool pnfs_wait_on_layoutreturn(struct inode *ino, struct rpc_task *task)
1605{
1606	struct nfs_inode *nfsi = NFS_I(ino);
1607        struct pnfs_layout_hdr *lo;
1608        bool sleep = false;
1609
1610	/* we might not have grabbed lo reference. so need to check under
1611	 * i_lock */
1612        spin_lock(&ino->i_lock);
1613        lo = nfsi->layout;
1614        if (lo && test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
1615                rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
1616                sleep = true;
1617	}
1618        spin_unlock(&ino->i_lock);
 
 
 
 
1619        return sleep;
1620}
1621
1622/*
1623 * Compare two layout segments for sorting into layout cache.
1624 * We want to preferentially return RW over RO layouts, so ensure those
1625 * are seen first.
1626 */
1627static s64
1628pnfs_lseg_range_cmp(const struct pnfs_layout_range *l1,
1629	   const struct pnfs_layout_range *l2)
1630{
1631	s64 d;
1632
1633	/* high offset > low offset */
1634	d = l1->offset - l2->offset;
1635	if (d)
1636		return d;
1637
1638	/* short length > long length */
1639	d = l2->length - l1->length;
1640	if (d)
1641		return d;
1642
1643	/* read > read/write */
1644	return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
1645}
1646
1647static bool
1648pnfs_lseg_range_is_after(const struct pnfs_layout_range *l1,
1649		const struct pnfs_layout_range *l2)
1650{
1651	return pnfs_lseg_range_cmp(l1, l2) > 0;
1652}
1653
1654static bool
1655pnfs_lseg_no_merge(struct pnfs_layout_segment *lseg,
1656		struct pnfs_layout_segment *old)
1657{
1658	return false;
1659}
1660
1661void
1662pnfs_generic_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1663		   struct pnfs_layout_segment *lseg,
1664		   bool (*is_after)(const struct pnfs_layout_range *,
1665			   const struct pnfs_layout_range *),
1666		   bool (*do_merge)(struct pnfs_layout_segment *,
1667			   struct pnfs_layout_segment *),
1668		   struct list_head *free_me)
1669{
1670	struct pnfs_layout_segment *lp, *tmp;
1671
1672	dprintk("%s:Begin\n", __func__);
1673
1674	list_for_each_entry_safe(lp, tmp, &lo->plh_segs, pls_list) {
1675		if (test_bit(NFS_LSEG_VALID, &lp->pls_flags) == 0)
1676			continue;
1677		if (do_merge(lseg, lp)) {
1678			mark_lseg_invalid(lp, free_me);
1679			continue;
1680		}
1681		if (is_after(&lseg->pls_range, &lp->pls_range))
1682			continue;
1683		list_add_tail(&lseg->pls_list, &lp->pls_list);
1684		dprintk("%s: inserted lseg %p "
1685			"iomode %d offset %llu length %llu before "
1686			"lp %p iomode %d offset %llu length %llu\n",
1687			__func__, lseg, lseg->pls_range.iomode,
1688			lseg->pls_range.offset, lseg->pls_range.length,
1689			lp, lp->pls_range.iomode, lp->pls_range.offset,
1690			lp->pls_range.length);
1691		goto out;
1692	}
1693	list_add_tail(&lseg->pls_list, &lo->plh_segs);
1694	dprintk("%s: inserted lseg %p "
1695		"iomode %d offset %llu length %llu at tail\n",
1696		__func__, lseg, lseg->pls_range.iomode,
1697		lseg->pls_range.offset, lseg->pls_range.length);
1698out:
1699	pnfs_get_layout_hdr(lo);
1700
1701	dprintk("%s:Return\n", __func__);
1702}
1703EXPORT_SYMBOL_GPL(pnfs_generic_layout_insert_lseg);
1704
1705static void
1706pnfs_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1707		   struct pnfs_layout_segment *lseg,
1708		   struct list_head *free_me)
1709{
1710	struct inode *inode = lo->plh_inode;
1711	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
1712
1713	if (ld->add_lseg != NULL)
1714		ld->add_lseg(lo, lseg, free_me);
1715	else
1716		pnfs_generic_layout_insert_lseg(lo, lseg,
1717				pnfs_lseg_range_is_after,
1718				pnfs_lseg_no_merge,
1719				free_me);
1720}
1721
1722static struct pnfs_layout_hdr *
1723alloc_init_layout_hdr(struct inode *ino,
1724		      struct nfs_open_context *ctx,
1725		      gfp_t gfp_flags)
1726{
1727	struct pnfs_layout_hdr *lo;
1728
1729	lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
1730	if (!lo)
1731		return NULL;
1732	refcount_set(&lo->plh_refcount, 1);
1733	INIT_LIST_HEAD(&lo->plh_layouts);
1734	INIT_LIST_HEAD(&lo->plh_segs);
1735	INIT_LIST_HEAD(&lo->plh_return_segs);
1736	INIT_LIST_HEAD(&lo->plh_bulk_destroy);
1737	lo->plh_inode = ino;
1738	lo->plh_lc_cred = get_cred(ctx->cred);
1739	lo->plh_flags |= 1 << NFS_LAYOUT_INVALID_STID;
1740	return lo;
1741}
1742
1743static struct pnfs_layout_hdr *
1744pnfs_find_alloc_layout(struct inode *ino,
1745		       struct nfs_open_context *ctx,
1746		       gfp_t gfp_flags)
1747	__releases(&ino->i_lock)
1748	__acquires(&ino->i_lock)
1749{
1750	struct nfs_inode *nfsi = NFS_I(ino);
1751	struct pnfs_layout_hdr *new = NULL;
1752
1753	dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
1754
1755	if (nfsi->layout != NULL)
1756		goto out_existing;
1757	spin_unlock(&ino->i_lock);
1758	new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
1759	spin_lock(&ino->i_lock);
1760
1761	if (likely(nfsi->layout == NULL)) {	/* Won the race? */
1762		nfsi->layout = new;
1763		return new;
1764	} else if (new != NULL)
1765		pnfs_free_layout_hdr(new);
1766out_existing:
1767	pnfs_get_layout_hdr(nfsi->layout);
1768	return nfsi->layout;
1769}
1770
1771/*
1772 * iomode matching rules:
1773 * iomode	lseg	strict match
1774 *                      iomode
1775 * -----	-----	------ -----
1776 * ANY		READ	N/A    true
1777 * ANY		RW	N/A    true
1778 * RW		READ	N/A    false
1779 * RW		RW	N/A    true
1780 * READ		READ	N/A    true
1781 * READ		RW	true   false
1782 * READ		RW	false  true
1783 */
1784static bool
1785pnfs_lseg_range_match(const struct pnfs_layout_range *ls_range,
1786		 const struct pnfs_layout_range *range,
1787		 bool strict_iomode)
1788{
1789	struct pnfs_layout_range range1;
1790
1791	if ((range->iomode == IOMODE_RW &&
1792	     ls_range->iomode != IOMODE_RW) ||
1793	    (range->iomode != ls_range->iomode &&
1794	     strict_iomode) ||
1795	    !pnfs_lseg_range_intersecting(ls_range, range))
1796		return false;
1797
1798	/* range1 covers only the first byte in the range */
1799	range1 = *range;
1800	range1.length = 1;
1801	return pnfs_lseg_range_contained(ls_range, &range1);
1802}
1803
1804/*
1805 * lookup range in layout
1806 */
1807static struct pnfs_layout_segment *
1808pnfs_find_lseg(struct pnfs_layout_hdr *lo,
1809		struct pnfs_layout_range *range,
1810		bool strict_iomode)
1811{
1812	struct pnfs_layout_segment *lseg, *ret = NULL;
1813
1814	dprintk("%s:Begin\n", __func__);
1815
1816	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
1817		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
1818		    pnfs_lseg_range_match(&lseg->pls_range, range,
1819					  strict_iomode)) {
1820			ret = pnfs_get_lseg(lseg);
1821			break;
1822		}
1823	}
1824
1825	dprintk("%s:Return lseg %p ref %d\n",
1826		__func__, ret, ret ? refcount_read(&ret->pls_refcount) : 0);
1827	return ret;
1828}
1829
1830/*
1831 * Use mdsthreshold hints set at each OPEN to determine if I/O should go
1832 * to the MDS or over pNFS
1833 *
1834 * The nfs_inode read_io and write_io fields are cumulative counters reset
1835 * when there are no layout segments. Note that in pnfs_update_layout iomode
1836 * is set to IOMODE_READ for a READ request, and set to IOMODE_RW for a
1837 * WRITE request.
1838 *
1839 * A return of true means use MDS I/O.
1840 *
1841 * From rfc 5661:
1842 * If a file's size is smaller than the file size threshold, data accesses
1843 * SHOULD be sent to the metadata server.  If an I/O request has a length that
1844 * is below the I/O size threshold, the I/O SHOULD be sent to the metadata
1845 * server.  If both file size and I/O size are provided, the client SHOULD
1846 * reach or exceed  both thresholds before sending its read or write
1847 * requests to the data server.
1848 */
1849static bool pnfs_within_mdsthreshold(struct nfs_open_context *ctx,
1850				     struct inode *ino, int iomode)
1851{
1852	struct nfs4_threshold *t = ctx->mdsthreshold;
1853	struct nfs_inode *nfsi = NFS_I(ino);
1854	loff_t fsize = i_size_read(ino);
1855	bool size = false, size_set = false, io = false, io_set = false, ret = false;
1856
1857	if (t == NULL)
1858		return ret;
1859
1860	dprintk("%s bm=0x%x rd_sz=%llu wr_sz=%llu rd_io=%llu wr_io=%llu\n",
1861		__func__, t->bm, t->rd_sz, t->wr_sz, t->rd_io_sz, t->wr_io_sz);
1862
1863	switch (iomode) {
1864	case IOMODE_READ:
1865		if (t->bm & THRESHOLD_RD) {
1866			dprintk("%s fsize %llu\n", __func__, fsize);
1867			size_set = true;
1868			if (fsize < t->rd_sz)
1869				size = true;
1870		}
1871		if (t->bm & THRESHOLD_RD_IO) {
1872			dprintk("%s nfsi->read_io %llu\n", __func__,
1873				nfsi->read_io);
1874			io_set = true;
1875			if (nfsi->read_io < t->rd_io_sz)
1876				io = true;
1877		}
1878		break;
1879	case IOMODE_RW:
1880		if (t->bm & THRESHOLD_WR) {
1881			dprintk("%s fsize %llu\n", __func__, fsize);
1882			size_set = true;
1883			if (fsize < t->wr_sz)
1884				size = true;
1885		}
1886		if (t->bm & THRESHOLD_WR_IO) {
1887			dprintk("%s nfsi->write_io %llu\n", __func__,
1888				nfsi->write_io);
1889			io_set = true;
1890			if (nfsi->write_io < t->wr_io_sz)
1891				io = true;
1892		}
1893		break;
1894	}
1895	if (size_set && io_set) {
1896		if (size && io)
1897			ret = true;
1898	} else if (size || io)
1899		ret = true;
1900
1901	dprintk("<-- %s size %d io %d ret %d\n", __func__, size, io, ret);
1902	return ret;
1903}
1904
1905static int pnfs_prepare_to_retry_layoutget(struct pnfs_layout_hdr *lo)
1906{
1907	/*
1908	 * send layoutcommit as it can hold up layoutreturn due to lseg
1909	 * reference
1910	 */
1911	pnfs_layoutcommit_inode(lo->plh_inode, false);
1912	return wait_on_bit_action(&lo->plh_flags, NFS_LAYOUT_RETURN,
1913				   nfs_wait_bit_killable,
1914				   TASK_KILLABLE|TASK_FREEZABLE_UNSAFE);
1915}
1916
1917static void nfs_layoutget_begin(struct pnfs_layout_hdr *lo)
1918{
1919	atomic_inc(&lo->plh_outstanding);
1920}
1921
1922static void nfs_layoutget_end(struct pnfs_layout_hdr *lo)
1923{
1924	if (atomic_dec_and_test(&lo->plh_outstanding) &&
1925	    test_and_clear_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags))
1926		wake_up_bit(&lo->plh_flags, NFS_LAYOUT_DRAIN);
1927}
1928
1929static bool pnfs_is_first_layoutget(struct pnfs_layout_hdr *lo)
1930{
1931	return test_bit(NFS_LAYOUT_FIRST_LAYOUTGET, &lo->plh_flags);
1932}
1933
1934static void pnfs_clear_first_layoutget(struct pnfs_layout_hdr *lo)
1935{
1936	unsigned long *bitlock = &lo->plh_flags;
1937
1938	clear_bit_unlock(NFS_LAYOUT_FIRST_LAYOUTGET, bitlock);
1939	smp_mb__after_atomic();
1940	wake_up_bit(bitlock, NFS_LAYOUT_FIRST_LAYOUTGET);
1941}
1942
1943static void _add_to_server_list(struct pnfs_layout_hdr *lo,
1944				struct nfs_server *server)
1945{
1946	if (!test_and_set_bit(NFS_LAYOUT_HASHED, &lo->plh_flags)) {
1947		struct nfs_client *clp = server->nfs_client;
1948
1949		/* The lo must be on the clp list if there is any
1950		 * chance of a CB_LAYOUTRECALL(FILE) coming in.
1951		 */
1952		spin_lock(&clp->cl_lock);
1953		list_add_tail_rcu(&lo->plh_layouts, &server->layouts);
1954		spin_unlock(&clp->cl_lock);
1955	}
1956}
1957
1958/*
1959 * Layout segment is retreived from the server if not cached.
1960 * The appropriate layout segment is referenced and returned to the caller.
1961 */
1962struct pnfs_layout_segment *
1963pnfs_update_layout(struct inode *ino,
1964		   struct nfs_open_context *ctx,
1965		   loff_t pos,
1966		   u64 count,
1967		   enum pnfs_iomode iomode,
1968		   bool strict_iomode,
1969		   gfp_t gfp_flags)
1970{
1971	struct pnfs_layout_range arg = {
1972		.iomode = iomode,
1973		.offset = pos,
1974		.length = count,
1975	};
1976	unsigned pg_offset;
1977	struct nfs_server *server = NFS_SERVER(ino);
1978	struct nfs_client *clp = server->nfs_client;
1979	struct pnfs_layout_hdr *lo = NULL;
1980	struct pnfs_layout_segment *lseg = NULL;
1981	struct nfs4_layoutget *lgp;
1982	nfs4_stateid stateid;
1983	struct nfs4_exception exception = {
1984		.inode = ino,
1985	};
1986	unsigned long giveup = jiffies + (clp->cl_lease_time << 1);
1987	bool first;
1988
1989	if (!pnfs_enabled_sb(NFS_SERVER(ino))) {
1990		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1991				 PNFS_UPDATE_LAYOUT_NO_PNFS);
1992		goto out;
1993	}
1994
 
 
 
 
 
 
1995	if (pnfs_within_mdsthreshold(ctx, ino, iomode)) {
1996		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1997				 PNFS_UPDATE_LAYOUT_MDSTHRESH);
1998		goto out;
1999	}
2000
2001lookup_again:
2002	lseg = ERR_PTR(nfs4_client_recover_expired_lease(clp));
2003	if (IS_ERR(lseg))
2004		goto out;
2005	first = false;
2006	spin_lock(&ino->i_lock);
2007	lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
2008	if (lo == NULL) {
2009		spin_unlock(&ino->i_lock);
2010		lseg = ERR_PTR(-ENOMEM);
2011		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2012				 PNFS_UPDATE_LAYOUT_NOMEM);
2013		goto out;
2014	}
2015
2016	/* Do we even need to bother with this? */
2017	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
2018		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2019				 PNFS_UPDATE_LAYOUT_BULK_RECALL);
2020		dprintk("%s matches recall, use MDS\n", __func__);
2021		goto out_unlock;
2022	}
2023
2024	/* if LAYOUTGET already failed once we don't try again */
2025	if (pnfs_layout_io_test_failed(lo, iomode)) {
2026		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2027				 PNFS_UPDATE_LAYOUT_IO_TEST_FAIL);
2028		goto out_unlock;
2029	}
2030
2031	/*
2032	 * If the layout segment list is empty, but there are outstanding
2033	 * layoutget calls, then they might be subject to a layoutrecall.
2034	 */
2035	if (test_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags) &&
2036	    atomic_read(&lo->plh_outstanding) != 0) {
2037		spin_unlock(&ino->i_lock);
2038		lseg = ERR_PTR(wait_on_bit(&lo->plh_flags, NFS_LAYOUT_DRAIN,
2039					   TASK_KILLABLE));
2040		if (IS_ERR(lseg))
2041			goto out_put_layout_hdr;
2042		pnfs_put_layout_hdr(lo);
2043		goto lookup_again;
2044	}
2045
2046	/*
2047	 * Because we free lsegs when sending LAYOUTRETURN, we need to wait
2048	 * for LAYOUTRETURN.
2049	 */
2050	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
2051		spin_unlock(&ino->i_lock);
2052		dprintk("%s wait for layoutreturn\n", __func__);
2053		lseg = ERR_PTR(pnfs_prepare_to_retry_layoutget(lo));
2054		if (!IS_ERR(lseg)) {
2055			pnfs_put_layout_hdr(lo);
2056			dprintk("%s retrying\n", __func__);
2057			trace_pnfs_update_layout(ino, pos, count, iomode, lo,
2058						 lseg,
2059						 PNFS_UPDATE_LAYOUT_RETRY);
2060			goto lookup_again;
2061		}
2062		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2063					 PNFS_UPDATE_LAYOUT_RETURN);
2064		goto out_put_layout_hdr;
2065	}
2066
2067	lseg = pnfs_find_lseg(lo, &arg, strict_iomode);
2068	if (lseg) {
2069		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2070				PNFS_UPDATE_LAYOUT_FOUND_CACHED);
2071		goto out_unlock;
2072	}
2073
2074	/*
2075	 * Choose a stateid for the LAYOUTGET. If we don't have a layout
2076	 * stateid, or it has been invalidated, then we must use the open
2077	 * stateid.
2078	 */
2079	if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags)) {
2080		int status;
2081
2082		/*
2083		 * The first layoutget for the file. Need to serialize per
2084		 * RFC 5661 Errata 3208.
2085		 */
2086		if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET,
2087				     &lo->plh_flags)) {
2088			spin_unlock(&ino->i_lock);
2089			lseg = ERR_PTR(wait_on_bit(&lo->plh_flags,
2090						NFS_LAYOUT_FIRST_LAYOUTGET,
2091						TASK_KILLABLE));
2092			if (IS_ERR(lseg))
2093				goto out_put_layout_hdr;
2094			pnfs_put_layout_hdr(lo);
2095			dprintk("%s retrying\n", __func__);
2096			goto lookup_again;
2097		}
 
 
 
 
 
 
 
 
 
 
 
2098
 
 
 
 
 
2099		spin_unlock(&ino->i_lock);
2100		first = true;
2101		status = nfs4_select_rw_stateid(ctx->state,
2102					iomode == IOMODE_RW ? FMODE_WRITE : FMODE_READ,
2103					NULL, &stateid, NULL);
2104		if (status != 0) {
2105			lseg = ERR_PTR(status);
2106			trace_pnfs_update_layout(ino, pos, count,
2107					iomode, lo, lseg,
2108					PNFS_UPDATE_LAYOUT_INVALID_OPEN);
2109			nfs4_schedule_stateid_recovery(server, ctx->state);
2110			pnfs_clear_first_layoutget(lo);
2111			pnfs_put_layout_hdr(lo);
 
2112			goto lookup_again;
2113		}
2114		spin_lock(&ino->i_lock);
2115	} else {
2116		nfs4_stateid_copy(&stateid, &lo->plh_stateid);
2117	}
2118
2119	if (pnfs_layoutgets_blocked(lo)) {
2120		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2121				PNFS_UPDATE_LAYOUT_BLOCKED);
2122		goto out_unlock;
2123	}
2124	nfs_layoutget_begin(lo);
2125	spin_unlock(&ino->i_lock);
2126
2127	_add_to_server_list(lo, server);
 
 
 
 
 
 
 
 
2128
2129	pg_offset = arg.offset & ~PAGE_MASK;
2130	if (pg_offset) {
2131		arg.offset -= pg_offset;
2132		arg.length += pg_offset;
2133	}
2134	if (arg.length != NFS4_MAX_UINT64)
2135		arg.length = PAGE_ALIGN(arg.length);
2136
2137	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &stateid, &arg, gfp_flags);
2138	if (!lgp) {
2139		lseg = ERR_PTR(-ENOMEM);
2140		trace_pnfs_update_layout(ino, pos, count, iomode, lo, NULL,
2141					 PNFS_UPDATE_LAYOUT_NOMEM);
2142		nfs_layoutget_end(lo);
2143		goto out_put_layout_hdr;
2144	}
2145
2146	lgp->lo = lo;
2147	pnfs_get_layout_hdr(lo);
2148
2149	lseg = nfs4_proc_layoutget(lgp, &exception);
2150	trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2151				 PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET);
2152	nfs_layoutget_end(lo);
2153	if (IS_ERR(lseg)) {
2154		switch(PTR_ERR(lseg)) {
2155		case -EBUSY:
2156			if (time_after(jiffies, giveup))
2157				lseg = NULL;
2158			break;
2159		case -ERECALLCONFLICT:
2160		case -EAGAIN:
2161			break;
2162		case -ENODATA:
2163			/* The server returned NFS4ERR_LAYOUTUNAVAILABLE */
2164			pnfs_layout_set_fail_bit(
2165				lo, pnfs_iomode_to_fail_bit(iomode));
2166			lseg = NULL;
2167			goto out_put_layout_hdr;
2168		default:
2169			if (!nfs_error_is_fatal(PTR_ERR(lseg))) {
2170				pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2171				lseg = NULL;
2172			}
2173			goto out_put_layout_hdr;
2174		}
2175		if (lseg) {
2176			if (!exception.retry)
2177				goto out_put_layout_hdr;
2178			if (first)
2179				pnfs_clear_first_layoutget(lo);
2180			trace_pnfs_update_layout(ino, pos, count,
2181				iomode, lo, lseg, PNFS_UPDATE_LAYOUT_RETRY);
2182			pnfs_put_layout_hdr(lo);
2183			goto lookup_again;
2184		}
2185	} else {
2186		pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2187	}
2188
2189out_put_layout_hdr:
2190	if (first)
2191		pnfs_clear_first_layoutget(lo);
2192	trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
2193				 PNFS_UPDATE_LAYOUT_EXIT);
2194	pnfs_put_layout_hdr(lo);
2195out:
2196	dprintk("%s: inode %s/%llu pNFS layout segment %s for "
2197			"(%s, offset: %llu, length: %llu)\n",
2198			__func__, ino->i_sb->s_id,
2199			(unsigned long long)NFS_FILEID(ino),
2200			IS_ERR_OR_NULL(lseg) ? "not found" : "found",
2201			iomode==IOMODE_RW ?  "read/write" : "read-only",
2202			(unsigned long long)pos,
2203			(unsigned long long)count);
2204	return lseg;
2205out_unlock:
2206	spin_unlock(&ino->i_lock);
2207	goto out_put_layout_hdr;
2208}
2209EXPORT_SYMBOL_GPL(pnfs_update_layout);
2210
2211static bool
2212pnfs_sanity_check_layout_range(struct pnfs_layout_range *range)
2213{
2214	switch (range->iomode) {
2215	case IOMODE_READ:
2216	case IOMODE_RW:
2217		break;
2218	default:
2219		return false;
2220	}
2221	if (range->offset == NFS4_MAX_UINT64)
2222		return false;
2223	if (range->length == 0)
2224		return false;
2225	if (range->length != NFS4_MAX_UINT64 &&
2226	    range->length > NFS4_MAX_UINT64 - range->offset)
2227		return false;
2228	return true;
2229}
2230
2231static struct pnfs_layout_hdr *
2232_pnfs_grab_empty_layout(struct inode *ino, struct nfs_open_context *ctx)
2233{
2234	struct pnfs_layout_hdr *lo;
2235
2236	spin_lock(&ino->i_lock);
2237	lo = pnfs_find_alloc_layout(ino, ctx, nfs_io_gfp_mask());
2238	if (!lo)
2239		goto out_unlock;
2240	if (!test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags))
2241		goto out_unlock;
2242	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
2243		goto out_unlock;
2244	if (pnfs_layoutgets_blocked(lo))
2245		goto out_unlock;
2246	if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET, &lo->plh_flags))
2247		goto out_unlock;
2248	nfs_layoutget_begin(lo);
2249	spin_unlock(&ino->i_lock);
2250	_add_to_server_list(lo, NFS_SERVER(ino));
2251	return lo;
2252
2253out_unlock:
2254	spin_unlock(&ino->i_lock);
2255	pnfs_put_layout_hdr(lo);
2256	return NULL;
2257}
2258
2259static void _lgopen_prepare_attached(struct nfs4_opendata *data,
2260				     struct nfs_open_context *ctx)
2261{
2262	struct inode *ino = data->dentry->d_inode;
2263	struct pnfs_layout_range rng = {
2264		.iomode = (data->o_arg.fmode & FMODE_WRITE) ?
2265			  IOMODE_RW: IOMODE_READ,
2266		.offset = 0,
2267		.length = NFS4_MAX_UINT64,
2268	};
2269	struct nfs4_layoutget *lgp;
2270	struct pnfs_layout_hdr *lo;
2271
2272	/* Heuristic: don't send layoutget if we have cached data */
2273	if (rng.iomode == IOMODE_READ &&
2274	   (i_size_read(ino) == 0 || ino->i_mapping->nrpages != 0))
2275		return;
2276
2277	lo = _pnfs_grab_empty_layout(ino, ctx);
2278	if (!lo)
2279		return;
2280	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &current_stateid, &rng,
2281					     nfs_io_gfp_mask());
2282	if (!lgp) {
2283		pnfs_clear_first_layoutget(lo);
2284		nfs_layoutget_end(lo);
2285		pnfs_put_layout_hdr(lo);
2286		return;
2287	}
2288	lgp->lo = lo;
2289	data->lgp = lgp;
2290	data->o_arg.lg_args = &lgp->args;
2291	data->o_res.lg_res = &lgp->res;
2292}
2293
2294static void _lgopen_prepare_floating(struct nfs4_opendata *data,
2295				     struct nfs_open_context *ctx)
2296{
2297	struct inode *ino = data->dentry->d_inode;
2298	struct pnfs_layout_range rng = {
2299		.iomode = (data->o_arg.fmode & FMODE_WRITE) ?
2300			  IOMODE_RW: IOMODE_READ,
2301		.offset = 0,
2302		.length = NFS4_MAX_UINT64,
2303	};
2304	struct nfs4_layoutget *lgp;
2305
2306	lgp = pnfs_alloc_init_layoutget_args(ino, ctx, &current_stateid, &rng,
2307					     nfs_io_gfp_mask());
2308	if (!lgp)
2309		return;
2310	data->lgp = lgp;
2311	data->o_arg.lg_args = &lgp->args;
2312	data->o_res.lg_res = &lgp->res;
2313}
2314
2315void pnfs_lgopen_prepare(struct nfs4_opendata *data,
2316			 struct nfs_open_context *ctx)
2317{
2318	struct nfs_server *server = NFS_SERVER(data->dir->d_inode);
2319
2320	if (!(pnfs_enabled_sb(server) &&
2321	      server->pnfs_curr_ld->flags & PNFS_LAYOUTGET_ON_OPEN))
2322		return;
2323	/* Could check on max_ops, but currently hardcoded high enough */
2324	if (!nfs_server_capable(data->dir->d_inode, NFS_CAP_LGOPEN))
2325		return;
2326	if (data->lgp)
2327		return;
2328	if (data->state)
2329		_lgopen_prepare_attached(data, ctx);
2330	else
2331		_lgopen_prepare_floating(data, ctx);
2332}
2333
2334void pnfs_parse_lgopen(struct inode *ino, struct nfs4_layoutget *lgp,
2335		       struct nfs_open_context *ctx)
2336{
2337	struct pnfs_layout_hdr *lo;
2338	struct pnfs_layout_segment *lseg;
2339	struct nfs_server *srv = NFS_SERVER(ino);
2340	u32 iomode;
2341
2342	if (!lgp)
2343		return;
2344	dprintk("%s: entered with status %i\n", __func__, lgp->res.status);
2345	if (lgp->res.status) {
2346		switch (lgp->res.status) {
2347		default:
2348			break;
2349		/*
2350		 * Halt lgopen attempts if the server doesn't recognise
2351		 * the "current stateid" value, the layout type, or the
2352		 * layoutget operation as being valid.
2353		 * Also if it complains about too many ops in the compound
2354		 * or of the request/reply being too big.
2355		 */
2356		case -NFS4ERR_BAD_STATEID:
2357		case -NFS4ERR_NOTSUPP:
2358		case -NFS4ERR_REP_TOO_BIG:
2359		case -NFS4ERR_REP_TOO_BIG_TO_CACHE:
2360		case -NFS4ERR_REQ_TOO_BIG:
2361		case -NFS4ERR_TOO_MANY_OPS:
2362		case -NFS4ERR_UNKNOWN_LAYOUTTYPE:
2363			srv->caps &= ~NFS_CAP_LGOPEN;
2364		}
2365		return;
2366	}
2367	if (!lgp->lo) {
2368		lo = _pnfs_grab_empty_layout(ino, ctx);
2369		if (!lo)
2370			return;
2371		lgp->lo = lo;
2372	} else
2373		lo = lgp->lo;
2374
2375	lseg = pnfs_layout_process(lgp);
2376	if (!IS_ERR(lseg)) {
2377		iomode = lgp->args.range.iomode;
2378		pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
2379		pnfs_put_lseg(lseg);
2380	}
2381}
2382
2383void nfs4_lgopen_release(struct nfs4_layoutget *lgp)
2384{
2385	if (lgp != NULL) {
2386		if (lgp->lo) {
2387			pnfs_clear_first_layoutget(lgp->lo);
2388			nfs_layoutget_end(lgp->lo);
2389		}
2390		pnfs_layoutget_free(lgp);
2391	}
2392}
2393
2394struct pnfs_layout_segment *
2395pnfs_layout_process(struct nfs4_layoutget *lgp)
2396{
2397	struct pnfs_layout_hdr *lo = lgp->lo;
2398	struct nfs4_layoutget_res *res = &lgp->res;
2399	struct pnfs_layout_segment *lseg;
2400	struct inode *ino = lo->plh_inode;
2401	LIST_HEAD(free_me);
 
2402
2403	if (!pnfs_sanity_check_layout_range(&res->range))
2404		return ERR_PTR(-EINVAL);
2405
2406	/* Inject layout blob into I/O device driver */
2407	lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
2408	if (IS_ERR_OR_NULL(lseg)) {
2409		if (!lseg)
2410			lseg = ERR_PTR(-ENOMEM);
2411
2412		dprintk("%s: Could not allocate layout: error %ld\n",
2413		       __func__, PTR_ERR(lseg));
2414		return lseg;
 
2415	}
2416
2417	pnfs_init_lseg(lo, lseg, &res->range, &res->stateid);
 
2418
2419	spin_lock(&ino->i_lock);
2420	if (pnfs_layoutgets_blocked(lo)) {
2421		dprintk("%s forget reply due to state\n", __func__);
2422		goto out_forget;
2423	}
2424
2425	if (test_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags) &&
2426	    !pnfs_is_first_layoutget(lo))
2427		goto out_forget;
2428
2429	if (nfs4_stateid_match_other(&lo->plh_stateid, &res->stateid)) {
2430		/* existing state ID, make sure the sequence number matches. */
2431		if (pnfs_layout_stateid_blocked(lo, &res->stateid)) {
2432			if (!pnfs_layout_is_valid(lo))
2433				lo->plh_barrier = 0;
2434			dprintk("%s forget reply due to sequence\n", __func__);
2435			goto out_forget;
 
2436		}
2437		pnfs_set_layout_stateid(lo, &res->stateid, lgp->cred, false);
2438	} else if (pnfs_layout_is_valid(lo)) {
2439		/*
2440		 * We got an entirely new state ID.  Mark all segments for the
2441		 * inode invalid, and retry the layoutget
 
2442		 */
2443		struct pnfs_layout_range range = {
2444			.iomode = IOMODE_ANY,
2445			.length = NFS4_MAX_UINT64,
2446		};
2447		pnfs_mark_matching_lsegs_return(lo, &free_me, &range, 0);
2448		goto out_forget;
2449	} else {
2450		/* We have a completely new layout */
2451		pnfs_set_layout_stateid(lo, &res->stateid, lgp->cred, true);
2452	}
2453
 
 
2454	pnfs_get_lseg(lseg);
2455	pnfs_layout_insert_lseg(lo, lseg, &free_me);
2456
2457
2458	if (res->return_on_close)
2459		set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
2460
2461	spin_unlock(&ino->i_lock);
2462	pnfs_free_lseg_list(&free_me);
2463	return lseg;
 
 
2464
2465out_forget:
2466	spin_unlock(&ino->i_lock);
2467	lseg->pls_layout = lo;
2468	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
2469	return ERR_PTR(-EAGAIN);
 
 
 
 
 
 
 
 
 
 
 
2470}
2471
2472/**
2473 * pnfs_mark_matching_lsegs_return - Free or return matching layout segments
2474 * @lo: pointer to layout header
2475 * @tmp_list: list header to be used with pnfs_free_lseg_list()
2476 * @return_range: describe layout segment ranges to be returned
2477 * @seq: stateid seqid to match
2478 *
2479 * This function is mainly intended for use by layoutrecall. It attempts
2480 * to free the layout segment immediately, or else to mark it for return
2481 * as soon as its reference count drops to zero.
2482 *
2483 * Returns
2484 * - 0: a layoutreturn needs to be scheduled.
2485 * - EBUSY: there are layout segment that are still in use.
2486 * - ENOENT: there are no layout segments that need to be returned.
2487 */
2488int
2489pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
2490				struct list_head *tmp_list,
2491				const struct pnfs_layout_range *return_range,
2492				u32 seq)
2493{
2494	struct pnfs_layout_segment *lseg, *next;
2495	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
2496	int remaining = 0;
2497
2498	dprintk("%s:Begin lo %p\n", __func__, lo);
2499
 
 
 
2500	assert_spin_locked(&lo->plh_inode->i_lock);
2501
2502	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
2503		tmp_list = &lo->plh_return_segs;
2504
2505	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
2506		if (pnfs_match_lseg_recall(lseg, return_range, seq)) {
2507			dprintk("%s: marking lseg %p iomode %d "
2508				"offset %llu length %llu\n", __func__,
2509				lseg, lseg->pls_range.iomode,
2510				lseg->pls_range.offset,
2511				lseg->pls_range.length);
2512			if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
2513				tmp_list = &lo->plh_return_segs;
2514			if (mark_lseg_invalid(lseg, tmp_list))
2515				continue;
2516			remaining++;
2517			set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
2518			pnfs_lseg_cancel_io(server, lseg);
2519		}
2520
2521	if (remaining) {
2522		pnfs_set_plh_return_info(lo, return_range->iomode, seq);
2523		return -EBUSY;
2524	}
2525
2526	if (!list_empty(&lo->plh_return_segs)) {
2527		pnfs_set_plh_return_info(lo, return_range->iomode, seq);
2528		return 0;
2529	}
2530
2531	return -ENOENT;
2532}
2533
2534static void
2535pnfs_mark_layout_for_return(struct inode *inode,
2536			    const struct pnfs_layout_range *range)
2537{
2538	struct pnfs_layout_hdr *lo;
 
 
 
 
 
 
2539	bool return_now = false;
2540
2541	spin_lock(&inode->i_lock);
2542	lo = NFS_I(inode)->layout;
2543	if (!pnfs_layout_is_valid(lo)) {
2544		spin_unlock(&inode->i_lock);
2545		return;
2546	}
2547	pnfs_set_plh_return_info(lo, range->iomode, 0);
2548	/*
2549	 * mark all matching lsegs so that we are sure to have no live
2550	 * segments at hand when sending layoutreturn. See pnfs_put_lseg()
2551	 * for how it works.
2552	 */
2553	if (pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs, range, 0) != -EBUSY) {
2554		const struct cred *cred;
2555		nfs4_stateid stateid;
2556		enum pnfs_iomode iomode;
2557
2558		return_now = pnfs_prepare_layoutreturn(lo, &stateid, &cred, &iomode);
 
2559		spin_unlock(&inode->i_lock);
2560		if (return_now)
2561			pnfs_send_layoutreturn(lo, &stateid, &cred, iomode, false);
2562	} else {
2563		spin_unlock(&inode->i_lock);
2564		nfs_commit_inode(inode, 0);
2565	}
2566}
2567
2568void pnfs_error_mark_layout_for_return(struct inode *inode,
2569				       struct pnfs_layout_segment *lseg)
2570{
2571	struct pnfs_layout_range range = {
2572		.iomode = lseg->pls_range.iomode,
2573		.offset = 0,
2574		.length = NFS4_MAX_UINT64,
2575	};
2576
2577	pnfs_mark_layout_for_return(inode, &range);
2578}
2579EXPORT_SYMBOL_GPL(pnfs_error_mark_layout_for_return);
2580
2581static bool
2582pnfs_layout_can_be_returned(struct pnfs_layout_hdr *lo)
2583{
2584	return pnfs_layout_is_valid(lo) &&
2585		!test_bit(NFS_LAYOUT_INODE_FREEING, &lo->plh_flags) &&
2586		!test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
2587}
2588
2589static struct pnfs_layout_segment *
2590pnfs_find_first_lseg(struct pnfs_layout_hdr *lo,
2591		     const struct pnfs_layout_range *range,
2592		     enum pnfs_iomode iomode)
2593{
2594	struct pnfs_layout_segment *lseg;
2595
2596	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
2597		if (!test_bit(NFS_LSEG_VALID, &lseg->pls_flags))
2598			continue;
2599		if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
2600			continue;
2601		if (lseg->pls_range.iomode != iomode && iomode != IOMODE_ANY)
2602			continue;
2603		if (pnfs_lseg_range_intersecting(&lseg->pls_range, range))
2604			return lseg;
2605	}
2606	return NULL;
2607}
2608
2609/* Find open file states whose mode matches that of the range */
2610static bool
2611pnfs_should_return_unused_layout(struct pnfs_layout_hdr *lo,
2612				 const struct pnfs_layout_range *range)
2613{
2614	struct list_head *head;
2615	struct nfs_open_context *ctx;
2616	fmode_t mode = 0;
2617
2618	if (!pnfs_layout_can_be_returned(lo) ||
2619	    !pnfs_find_first_lseg(lo, range, range->iomode))
2620		return false;
2621
2622	head = &NFS_I(lo->plh_inode)->open_files;
2623	list_for_each_entry_rcu(ctx, head, list) {
2624		if (ctx->state)
2625			mode |= ctx->state->state & (FMODE_READ|FMODE_WRITE);
2626	}
2627
2628	switch (range->iomode) {
2629	default:
2630		break;
2631	case IOMODE_READ:
2632		mode &= ~FMODE_WRITE;
2633		break;
2634	case IOMODE_RW:
2635		if (pnfs_find_first_lseg(lo, range, IOMODE_READ))
2636			mode &= ~FMODE_READ;
2637	}
2638	return mode == 0;
2639}
2640
2641static int pnfs_layout_return_unused_byserver(struct nfs_server *server,
2642					      void *data)
2643{
2644	const struct pnfs_layout_range *range = data;
2645	const struct cred *cred;
2646	struct pnfs_layout_hdr *lo;
2647	struct inode *inode;
2648	nfs4_stateid stateid;
2649	enum pnfs_iomode iomode;
2650
2651restart:
2652	rcu_read_lock();
2653	list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
2654		inode = lo->plh_inode;
2655		if (!inode || !pnfs_layout_can_be_returned(lo) ||
2656		    test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
2657			continue;
2658		spin_lock(&inode->i_lock);
2659		if (!lo->plh_inode ||
2660		    !pnfs_should_return_unused_layout(lo, range)) {
2661			spin_unlock(&inode->i_lock);
2662			continue;
2663		}
2664		pnfs_get_layout_hdr(lo);
2665		pnfs_set_plh_return_info(lo, range->iomode, 0);
2666		if (pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs,
2667						    range, 0) != 0 ||
2668		    !pnfs_prepare_layoutreturn(lo, &stateid, &cred, &iomode)) {
2669			spin_unlock(&inode->i_lock);
2670			rcu_read_unlock();
2671			pnfs_put_layout_hdr(lo);
2672			cond_resched();
2673			goto restart;
2674		}
2675		spin_unlock(&inode->i_lock);
2676		rcu_read_unlock();
2677		pnfs_send_layoutreturn(lo, &stateid, &cred, iomode, false);
2678		pnfs_put_layout_hdr(lo);
2679		cond_resched();
2680		goto restart;
2681	}
2682	rcu_read_unlock();
2683	return 0;
2684}
2685
2686void
2687pnfs_layout_return_unused_byclid(struct nfs_client *clp,
2688				 enum pnfs_iomode iomode)
2689{
2690	struct pnfs_layout_range range = {
2691		.iomode = iomode,
2692		.offset = 0,
2693		.length = NFS4_MAX_UINT64,
2694	};
2695
2696	nfs_client_for_each_server(clp, pnfs_layout_return_unused_byserver,
2697			&range);
2698}
2699
2700void
2701pnfs_generic_pg_check_layout(struct nfs_pageio_descriptor *pgio)
2702{
2703	if (pgio->pg_lseg == NULL ||
2704	    test_bit(NFS_LSEG_VALID, &pgio->pg_lseg->pls_flags))
2705		return;
2706	pnfs_put_lseg(pgio->pg_lseg);
2707	pgio->pg_lseg = NULL;
2708}
2709EXPORT_SYMBOL_GPL(pnfs_generic_pg_check_layout);
2710
2711/*
2712 * Check for any intersection between the request and the pgio->pg_lseg,
2713 * and if none, put this pgio->pg_lseg away.
2714 */
2715void
2716pnfs_generic_pg_check_range(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
2717{
2718	if (pgio->pg_lseg && !pnfs_lseg_request_intersecting(pgio->pg_lseg, req)) {
2719		pnfs_put_lseg(pgio->pg_lseg);
2720		pgio->pg_lseg = NULL;
2721	}
2722}
2723EXPORT_SYMBOL_GPL(pnfs_generic_pg_check_range);
2724
2725void
2726pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
2727{
2728	u64 rd_size;
2729
2730	pnfs_generic_pg_check_layout(pgio);
2731	pnfs_generic_pg_check_range(pgio, req);
2732	if (pgio->pg_lseg == NULL) {
2733		if (pgio->pg_dreq == NULL)
2734			rd_size = i_size_read(pgio->pg_inode) - req_offset(req);
2735		else
2736			rd_size = nfs_dreq_bytes_left(pgio->pg_dreq,
2737						      req_offset(req));
2738
2739		pgio->pg_lseg =
2740			pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
2741					   req_offset(req), rd_size,
2742					   IOMODE_READ, false,
2743					   nfs_io_gfp_mask());
 
2744		if (IS_ERR(pgio->pg_lseg)) {
2745			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2746			pgio->pg_lseg = NULL;
2747			return;
2748		}
2749	}
2750	/* If no lseg, fall back to read through mds */
2751	if (pgio->pg_lseg == NULL)
2752		nfs_pageio_reset_read_mds(pgio);
2753
2754}
2755EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);
2756
2757void
2758pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
2759			   struct nfs_page *req, u64 wb_size)
2760{
2761	pnfs_generic_pg_check_layout(pgio);
2762	pnfs_generic_pg_check_range(pgio, req);
2763	if (pgio->pg_lseg == NULL) {
2764		pgio->pg_lseg =
2765			pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
2766					   req_offset(req), wb_size, IOMODE_RW,
2767					   false, nfs_io_gfp_mask());
 
 
2768		if (IS_ERR(pgio->pg_lseg)) {
2769			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2770			pgio->pg_lseg = NULL;
2771			return;
2772		}
2773	}
2774	/* If no lseg, fall back to write through mds */
2775	if (pgio->pg_lseg == NULL)
2776		nfs_pageio_reset_write_mds(pgio);
2777}
2778EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
2779
2780void
2781pnfs_generic_pg_cleanup(struct nfs_pageio_descriptor *desc)
2782{
2783	if (desc->pg_lseg) {
2784		pnfs_put_lseg(desc->pg_lseg);
2785		desc->pg_lseg = NULL;
2786	}
2787}
2788EXPORT_SYMBOL_GPL(pnfs_generic_pg_cleanup);
2789
2790/*
2791 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
2792 * of bytes (maximum @req->wb_bytes) that can be coalesced.
2793 */
2794size_t
2795pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio,
2796		     struct nfs_page *prev, struct nfs_page *req)
2797{
2798	unsigned int size;
2799	u64 seg_end, req_start, seg_left;
2800
2801	size = nfs_generic_pg_test(pgio, prev, req);
2802	if (!size)
2803		return 0;
2804
2805	/*
2806	 * 'size' contains the number of bytes left in the current page (up
2807	 * to the original size asked for in @req->wb_bytes).
2808	 *
2809	 * Calculate how many bytes are left in the layout segment
2810	 * and if there are less bytes than 'size', return that instead.
2811	 *
2812	 * Please also note that 'end_offset' is actually the offset of the
2813	 * first byte that lies outside the pnfs_layout_range. FIXME?
2814	 *
2815	 */
2816	if (pgio->pg_lseg) {
2817		seg_end = pnfs_end_offset(pgio->pg_lseg->pls_range.offset,
2818				     pgio->pg_lseg->pls_range.length);
2819		req_start = req_offset(req);
2820
2821		/* start of request is past the last byte of this segment */
2822		if (req_start >= seg_end)
 
 
 
 
 
2823			return 0;
 
2824
2825		/* adjust 'size' iff there are fewer bytes left in the
2826		 * segment than what nfs_generic_pg_test returned */
2827		seg_left = seg_end - req_start;
2828		if (seg_left < size)
2829			size = (unsigned int)seg_left;
2830	}
2831
2832	return size;
2833}
2834EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
2835
2836int pnfs_write_done_resend_to_mds(struct nfs_pgio_header *hdr)
2837{
2838	struct nfs_pageio_descriptor pgio;
2839
2840	/* Resend all requests through the MDS */
2841	nfs_pageio_init_write(&pgio, hdr->inode, FLUSH_STABLE, true,
2842			      hdr->completion_ops);
 
2843	return nfs_pageio_resend(&pgio, hdr);
2844}
2845EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
2846
2847static void pnfs_ld_handle_write_error(struct nfs_pgio_header *hdr)
2848{
2849
2850	dprintk("pnfs write error = %d\n", hdr->pnfs_error);
2851	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2852	    PNFS_LAYOUTRET_ON_ERROR) {
2853		pnfs_return_layout(hdr->inode);
2854	}
2855	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2856		hdr->task.tk_status = pnfs_write_done_resend_to_mds(hdr);
2857}
2858
2859/*
2860 * Called by non rpc-based layout drivers
2861 */
2862void pnfs_ld_write_done(struct nfs_pgio_header *hdr)
2863{
2864	if (likely(!hdr->pnfs_error)) {
2865		pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
2866				hdr->mds_offset + hdr->res.count);
2867		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
2868	}
2869	trace_nfs4_pnfs_write(hdr, hdr->pnfs_error);
2870	if (unlikely(hdr->pnfs_error))
2871		pnfs_ld_handle_write_error(hdr);
2872	hdr->mds_ops->rpc_release(hdr);
2873}
2874EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
2875
2876static void
2877pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
2878		struct nfs_pgio_header *hdr)
2879{
2880	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2881
2882	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2883		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
2884		nfs_pageio_reset_write_mds(desc);
2885		mirror->pg_recoalesce = 1;
2886	}
2887	hdr->completion_ops->completion(hdr);
 
2888}
2889
2890static enum pnfs_try_status
2891pnfs_try_to_write_data(struct nfs_pgio_header *hdr,
2892			const struct rpc_call_ops *call_ops,
2893			struct pnfs_layout_segment *lseg,
2894			int how)
2895{
2896	struct inode *inode = hdr->inode;
2897	enum pnfs_try_status trypnfs;
2898	struct nfs_server *nfss = NFS_SERVER(inode);
2899
2900	hdr->mds_ops = call_ops;
2901
2902	dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
2903		inode->i_ino, hdr->args.count, hdr->args.offset, how);
2904	trypnfs = nfss->pnfs_curr_ld->write_pagelist(hdr, how);
2905	if (trypnfs != PNFS_NOT_ATTEMPTED)
2906		nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
2907	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
2908	return trypnfs;
2909}
2910
2911static void
2912pnfs_do_write(struct nfs_pageio_descriptor *desc,
2913	      struct nfs_pgio_header *hdr, int how)
2914{
2915	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
2916	struct pnfs_layout_segment *lseg = desc->pg_lseg;
2917	enum pnfs_try_status trypnfs;
2918
2919	trypnfs = pnfs_try_to_write_data(hdr, call_ops, lseg, how);
2920	switch (trypnfs) {
2921	case PNFS_NOT_ATTEMPTED:
2922		pnfs_write_through_mds(desc, hdr);
2923		break;
2924	case PNFS_ATTEMPTED:
2925		break;
2926	case PNFS_TRY_AGAIN:
2927		/* cleanup hdr and prepare to redo pnfs */
2928		if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2929			struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2930			list_splice_init(&hdr->pages, &mirror->pg_list);
2931			mirror->pg_recoalesce = 1;
2932		}
2933		hdr->mds_ops->rpc_release(hdr);
2934	}
2935}
2936
2937static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
2938{
2939	pnfs_put_lseg(hdr->lseg);
2940	nfs_pgio_header_free(hdr);
2941}
2942
2943int
2944pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
2945{
2946	struct nfs_pgio_header *hdr;
2947	int ret;
2948
2949	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
2950	if (!hdr) {
2951		desc->pg_error = -ENOMEM;
2952		return desc->pg_error;
2953	}
2954	nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
2955
2956	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
2957	ret = nfs_generic_pgio(desc, hdr);
2958	if (!ret)
2959		pnfs_do_write(desc, hdr, desc->pg_ioflags);
2960
2961	return ret;
2962}
2963EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
2964
2965int pnfs_read_done_resend_to_mds(struct nfs_pgio_header *hdr)
2966{
2967	struct nfs_pageio_descriptor pgio;
2968
2969	/* Resend all requests through the MDS */
2970	nfs_pageio_init_read(&pgio, hdr->inode, true, hdr->completion_ops);
2971	return nfs_pageio_resend(&pgio, hdr);
2972}
2973EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
2974
2975static void pnfs_ld_handle_read_error(struct nfs_pgio_header *hdr)
2976{
2977	dprintk("pnfs read error = %d\n", hdr->pnfs_error);
2978	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2979	    PNFS_LAYOUTRET_ON_ERROR) {
2980		pnfs_return_layout(hdr->inode);
2981	}
2982	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2983		hdr->task.tk_status = pnfs_read_done_resend_to_mds(hdr);
2984}
2985
2986/*
2987 * Called by non rpc-based layout drivers
2988 */
2989void pnfs_ld_read_done(struct nfs_pgio_header *hdr)
2990{
2991	if (likely(!hdr->pnfs_error))
 
2992		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
 
2993	trace_nfs4_pnfs_read(hdr, hdr->pnfs_error);
2994	if (unlikely(hdr->pnfs_error))
2995		pnfs_ld_handle_read_error(hdr);
2996	hdr->mds_ops->rpc_release(hdr);
2997}
2998EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
2999
3000static void
3001pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
3002		struct nfs_pgio_header *hdr)
3003{
3004	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
3005
3006	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
3007		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
3008		nfs_pageio_reset_read_mds(desc);
3009		mirror->pg_recoalesce = 1;
3010	}
3011	hdr->completion_ops->completion(hdr);
 
3012}
3013
3014/*
3015 * Call the appropriate parallel I/O subsystem read function.
3016 */
3017static enum pnfs_try_status
3018pnfs_try_to_read_data(struct nfs_pgio_header *hdr,
3019		       const struct rpc_call_ops *call_ops,
3020		       struct pnfs_layout_segment *lseg)
3021{
3022	struct inode *inode = hdr->inode;
3023	struct nfs_server *nfss = NFS_SERVER(inode);
3024	enum pnfs_try_status trypnfs;
3025
3026	hdr->mds_ops = call_ops;
3027
3028	dprintk("%s: Reading ino:%lu %u@%llu\n",
3029		__func__, inode->i_ino, hdr->args.count, hdr->args.offset);
3030
3031	trypnfs = nfss->pnfs_curr_ld->read_pagelist(hdr);
3032	if (trypnfs != PNFS_NOT_ATTEMPTED)
3033		nfs_inc_stats(inode, NFSIOS_PNFS_READ);
3034	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
3035	return trypnfs;
3036}
3037
3038/* Resend all requests through pnfs. */
3039void pnfs_read_resend_pnfs(struct nfs_pgio_header *hdr,
3040			   unsigned int mirror_idx)
3041{
3042	struct nfs_pageio_descriptor pgio;
3043
3044	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
3045		/* Prevent deadlocks with layoutreturn! */
3046		pnfs_put_lseg(hdr->lseg);
3047		hdr->lseg = NULL;
3048
3049		nfs_pageio_init_read(&pgio, hdr->inode, false,
3050					hdr->completion_ops);
3051		pgio.pg_mirror_idx = mirror_idx;
3052		hdr->task.tk_status = nfs_pageio_resend(&pgio, hdr);
3053	}
3054}
3055EXPORT_SYMBOL_GPL(pnfs_read_resend_pnfs);
3056
3057static void
3058pnfs_do_read(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr)
3059{
3060	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
3061	struct pnfs_layout_segment *lseg = desc->pg_lseg;
3062	enum pnfs_try_status trypnfs;
 
3063
3064	trypnfs = pnfs_try_to_read_data(hdr, call_ops, lseg);
3065	switch (trypnfs) {
3066	case PNFS_NOT_ATTEMPTED:
 
3067		pnfs_read_through_mds(desc, hdr);
3068		break;
3069	case PNFS_ATTEMPTED:
3070		break;
3071	case PNFS_TRY_AGAIN:
3072		/* cleanup hdr and prepare to redo pnfs */
3073		if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
3074			struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
3075			list_splice_init(&hdr->pages, &mirror->pg_list);
3076			mirror->pg_recoalesce = 1;
3077		}
3078		hdr->mds_ops->rpc_release(hdr);
3079	}
3080}
3081
3082static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
3083{
3084	pnfs_put_lseg(hdr->lseg);
3085	nfs_pgio_header_free(hdr);
3086}
3087
3088int
3089pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
3090{
3091	struct nfs_pgio_header *hdr;
3092	int ret;
3093
3094	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
3095	if (!hdr) {
3096		desc->pg_error = -ENOMEM;
3097		return desc->pg_error;
3098	}
3099	nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
3100	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
3101	ret = nfs_generic_pgio(desc, hdr);
3102	if (!ret)
3103		pnfs_do_read(desc, hdr);
3104	return ret;
3105}
3106EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
3107
3108static void pnfs_clear_layoutcommitting(struct inode *inode)
3109{
3110	unsigned long *bitlock = &NFS_I(inode)->flags;
3111
3112	clear_bit_unlock(NFS_INO_LAYOUTCOMMITTING, bitlock);
3113	smp_mb__after_atomic();
3114	wake_up_bit(bitlock, NFS_INO_LAYOUTCOMMITTING);
3115}
3116
3117/*
3118 * There can be multiple RW segments.
3119 */
3120static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
3121{
3122	struct pnfs_layout_segment *lseg;
3123
3124	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
3125		if (lseg->pls_range.iomode == IOMODE_RW &&
3126		    test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
3127			list_add(&lseg->pls_lc_list, listp);
3128	}
3129}
3130
3131static void pnfs_list_write_lseg_done(struct inode *inode, struct list_head *listp)
3132{
3133	struct pnfs_layout_segment *lseg, *tmp;
3134
3135	/* Matched by references in pnfs_set_layoutcommit */
3136	list_for_each_entry_safe(lseg, tmp, listp, pls_lc_list) {
3137		list_del_init(&lseg->pls_lc_list);
3138		pnfs_put_lseg(lseg);
3139	}
3140
3141	pnfs_clear_layoutcommitting(inode);
3142}
3143
3144void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
3145{
3146	pnfs_layout_io_set_failed(lseg->pls_layout, lseg->pls_range.iomode);
3147}
3148EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
3149
3150void
3151pnfs_set_layoutcommit(struct inode *inode, struct pnfs_layout_segment *lseg,
3152		loff_t end_pos)
3153{
3154	struct nfs_inode *nfsi = NFS_I(inode);
3155	bool mark_as_dirty = false;
3156
3157	spin_lock(&inode->i_lock);
3158	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
3159		nfsi->layout->plh_lwb = end_pos;
3160		mark_as_dirty = true;
3161		dprintk("%s: Set layoutcommit for inode %lu ",
3162			__func__, inode->i_ino);
3163	} else if (end_pos > nfsi->layout->plh_lwb)
3164		nfsi->layout->plh_lwb = end_pos;
3165	if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags)) {
3166		/* references matched in nfs4_layoutcommit_release */
3167		pnfs_get_lseg(lseg);
3168	}
3169	spin_unlock(&inode->i_lock);
3170	dprintk("%s: lseg %p end_pos %llu\n",
3171		__func__, lseg, nfsi->layout->plh_lwb);
3172
3173	/* if pnfs_layoutcommit_inode() runs between inode locks, the next one
3174	 * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */
3175	if (mark_as_dirty)
3176		mark_inode_dirty_sync(inode);
3177}
3178EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
3179
3180void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data)
3181{
3182	struct nfs_server *nfss = NFS_SERVER(data->args.inode);
3183
3184	if (nfss->pnfs_curr_ld->cleanup_layoutcommit)
3185		nfss->pnfs_curr_ld->cleanup_layoutcommit(data);
3186	pnfs_list_write_lseg_done(data->args.inode, &data->lseg_list);
3187}
3188
3189/*
3190 * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
3191 * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
3192 * data to disk to allow the server to recover the data if it crashes.
3193 * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
3194 * is off, and a COMMIT is sent to a data server, or
3195 * if WRITEs to a data server return NFS_DATA_SYNC.
3196 */
3197int
3198pnfs_layoutcommit_inode(struct inode *inode, bool sync)
3199{
3200	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
3201	struct nfs4_layoutcommit_data *data;
3202	struct nfs_inode *nfsi = NFS_I(inode);
3203	loff_t end_pos;
3204	int status;
3205
3206	if (!pnfs_layoutcommit_outstanding(inode))
3207		return 0;
3208
3209	dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
3210
3211	status = -EAGAIN;
3212	if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
3213		if (!sync)
3214			goto out;
3215		status = wait_on_bit_lock_action(&nfsi->flags,
3216				NFS_INO_LAYOUTCOMMITTING,
3217				nfs_wait_bit_killable,
3218				TASK_KILLABLE|TASK_FREEZABLE_UNSAFE);
3219		if (status)
3220			goto out;
3221	}
3222
3223	status = -ENOMEM;
3224	/* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
3225	data = kzalloc(sizeof(*data), nfs_io_gfp_mask());
3226	if (!data)
3227		goto clear_layoutcommitting;
3228
3229	status = 0;
3230	spin_lock(&inode->i_lock);
3231	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
3232		goto out_unlock;
3233
3234	INIT_LIST_HEAD(&data->lseg_list);
3235	pnfs_list_write_lseg(inode, &data->lseg_list);
3236
3237	end_pos = nfsi->layout->plh_lwb;
3238
3239	nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
3240	data->cred = get_cred(nfsi->layout->plh_lc_cred);
3241	spin_unlock(&inode->i_lock);
3242
3243	data->args.inode = inode;
 
3244	nfs_fattr_init(&data->fattr);
3245	data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
3246	data->res.fattr = &data->fattr;
3247	if (end_pos != 0)
3248		data->args.lastbytewritten = end_pos - 1;
3249	else
3250		data->args.lastbytewritten = U64_MAX;
3251	data->res.server = NFS_SERVER(inode);
3252
3253	if (ld->prepare_layoutcommit) {
3254		status = ld->prepare_layoutcommit(&data->args);
3255		if (status) {
3256			put_cred(data->cred);
3257			spin_lock(&inode->i_lock);
3258			set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags);
3259			if (end_pos > nfsi->layout->plh_lwb)
3260				nfsi->layout->plh_lwb = end_pos;
3261			goto out_unlock;
3262		}
3263	}
3264
3265
3266	status = nfs4_proc_layoutcommit(data, sync);
3267out:
3268	if (status)
3269		mark_inode_dirty_sync(inode);
3270	dprintk("<-- %s status %d\n", __func__, status);
3271	return status;
3272out_unlock:
3273	spin_unlock(&inode->i_lock);
3274	kfree(data);
3275clear_layoutcommitting:
3276	pnfs_clear_layoutcommitting(inode);
3277	goto out;
3278}
3279EXPORT_SYMBOL_GPL(pnfs_layoutcommit_inode);
3280
3281int
3282pnfs_generic_sync(struct inode *inode, bool datasync)
3283{
3284	return pnfs_layoutcommit_inode(inode, true);
3285}
3286EXPORT_SYMBOL_GPL(pnfs_generic_sync);
3287
3288struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
3289{
3290	struct nfs4_threshold *thp;
3291
3292	thp = kzalloc(sizeof(*thp), nfs_io_gfp_mask());
3293	if (!thp) {
3294		dprintk("%s mdsthreshold allocation failed\n", __func__);
3295		return NULL;
3296	}
3297	return thp;
3298}
3299
3300#if IS_ENABLED(CONFIG_NFS_V4_2)
3301int
3302pnfs_report_layoutstat(struct inode *inode, gfp_t gfp_flags)
3303{
3304	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
3305	struct nfs_server *server = NFS_SERVER(inode);
3306	struct nfs_inode *nfsi = NFS_I(inode);
3307	struct nfs42_layoutstat_data *data;
3308	struct pnfs_layout_hdr *hdr;
3309	int status = 0;
3310
3311	if (!pnfs_enabled_sb(server) || !ld->prepare_layoutstats)
3312		goto out;
3313
3314	if (!nfs_server_capable(inode, NFS_CAP_LAYOUTSTATS))
3315		goto out;
3316
3317	if (test_and_set_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags))
3318		goto out;
3319
3320	spin_lock(&inode->i_lock);
3321	if (!NFS_I(inode)->layout) {
3322		spin_unlock(&inode->i_lock);
3323		goto out_clear_layoutstats;
3324	}
3325	hdr = NFS_I(inode)->layout;
3326	pnfs_get_layout_hdr(hdr);
3327	spin_unlock(&inode->i_lock);
3328
3329	data = kzalloc(sizeof(*data), gfp_flags);
3330	if (!data) {
3331		status = -ENOMEM;
3332		goto out_put;
3333	}
3334
3335	data->args.fh = NFS_FH(inode);
3336	data->args.inode = inode;
 
3337	status = ld->prepare_layoutstats(&data->args);
3338	if (status)
3339		goto out_free;
3340
3341	status = nfs42_proc_layoutstats_generic(NFS_SERVER(inode), data);
3342
3343out:
3344	dprintk("%s returns %d\n", __func__, status);
3345	return status;
3346
3347out_free:
3348	kfree(data);
3349out_put:
3350	pnfs_put_layout_hdr(hdr);
3351out_clear_layoutstats:
3352	smp_mb__before_atomic();
3353	clear_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags);
3354	smp_mb__after_atomic();
3355	goto out;
3356}
3357EXPORT_SYMBOL_GPL(pnfs_report_layoutstat);
3358#endif
3359
3360unsigned int layoutstats_timer;
3361module_param(layoutstats_timer, uint, 0644);
3362EXPORT_SYMBOL_GPL(layoutstats_timer);