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v3.1
   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 "internal.h"
  33#include "pnfs.h"
  34#include "iostat.h"
 
 
 
  35
  36#define NFSDBG_FACILITY		NFSDBG_PNFS
 
  37
  38/* Locking:
  39 *
  40 * pnfs_spinlock:
  41 *      protects pnfs_modules_tbl.
  42 */
  43static DEFINE_SPINLOCK(pnfs_spinlock);
  44
  45/*
  46 * pnfs_modules_tbl holds all pnfs modules
  47 */
  48static LIST_HEAD(pnfs_modules_tbl);
  49
 
 
 
 
 
 
 
 
  50/* Return the registered pnfs layout driver module matching given id */
  51static struct pnfs_layoutdriver_type *
  52find_pnfs_driver_locked(u32 id)
  53{
  54	struct pnfs_layoutdriver_type *local;
  55
  56	list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid)
  57		if (local->id == id)
  58			goto out;
  59	local = NULL;
  60out:
  61	dprintk("%s: Searching for id %u, found %p\n", __func__, id, local);
  62	return local;
  63}
  64
  65static struct pnfs_layoutdriver_type *
  66find_pnfs_driver(u32 id)
  67{
  68	struct pnfs_layoutdriver_type *local;
  69
  70	spin_lock(&pnfs_spinlock);
  71	local = find_pnfs_driver_locked(id);
 
 
 
 
  72	spin_unlock(&pnfs_spinlock);
  73	return local;
  74}
  75
  76void
  77unset_pnfs_layoutdriver(struct nfs_server *nfss)
  78{
  79	if (nfss->pnfs_curr_ld) {
  80		if (nfss->pnfs_curr_ld->clear_layoutdriver)
  81			nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
 
 
 
  82		module_put(nfss->pnfs_curr_ld->owner);
  83	}
  84	nfss->pnfs_curr_ld = NULL;
  85}
  86
  87/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  88 * Try to set the server's pnfs module to the pnfs layout type specified by id.
  89 * Currently only one pNFS layout driver per filesystem is supported.
  90 *
  91 * @id layout type. Zero (illegal layout type) indicates pNFS not in use.
  92 */
  93void
  94set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
  95		      u32 id)
  96{
  97	struct pnfs_layoutdriver_type *ld_type = NULL;
 
 
  98
  99	if (id == 0)
 100		goto out_no_driver;
 101	if (!(server->nfs_client->cl_exchange_flags &
 102		 (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
 103		printk(KERN_ERR "%s: id %u cl_exchange_flags 0x%x\n", __func__,
 104		       id, server->nfs_client->cl_exchange_flags);
 105		goto out_no_driver;
 106	}
 107	ld_type = find_pnfs_driver(id);
 108	if (!ld_type) {
 109		request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX, id);
 
 
 
 110		ld_type = find_pnfs_driver(id);
 111		if (!ld_type) {
 112			dprintk("%s: No pNFS module found for %u.\n",
 113				__func__, id);
 114			goto out_no_driver;
 115		}
 
 
 116	}
 117	if (!try_module_get(ld_type->owner)) {
 118		dprintk("%s: Could not grab reference on module\n", __func__);
 
 119		goto out_no_driver;
 120	}
 
 121	server->pnfs_curr_ld = ld_type;
 122	if (ld_type->set_layoutdriver
 123	    && ld_type->set_layoutdriver(server, mntfh)) {
 124		printk(KERN_ERR "%s: Error initializing pNFS layout driver %u.\n",
 125				__func__, id);
 126		module_put(ld_type->owner);
 127		goto out_no_driver;
 128	}
 
 
 129
 130	dprintk("%s: pNFS module for %u set\n", __func__, id);
 131	return;
 132
 133out_no_driver:
 134	dprintk("%s: Using NFSv4 I/O\n", __func__);
 135	server->pnfs_curr_ld = NULL;
 136}
 137
 138int
 139pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 140{
 141	int status = -EINVAL;
 142	struct pnfs_layoutdriver_type *tmp;
 143
 144	if (ld_type->id == 0) {
 145		printk(KERN_ERR "%s id 0 is reserved\n", __func__);
 146		return status;
 147	}
 148	if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
 149		printk(KERN_ERR "%s Layout driver must provide "
 150		       "alloc_lseg and free_lseg.\n", __func__);
 151		return status;
 152	}
 153
 154	spin_lock(&pnfs_spinlock);
 155	tmp = find_pnfs_driver_locked(ld_type->id);
 156	if (!tmp) {
 157		list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
 158		status = 0;
 159		dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
 160			ld_type->name);
 161	} else {
 162		printk(KERN_ERR "%s Module with id %d already loaded!\n",
 163			__func__, ld_type->id);
 164	}
 165	spin_unlock(&pnfs_spinlock);
 166
 167	return status;
 168}
 169EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);
 170
 171void
 172pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 173{
 174	dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
 175	spin_lock(&pnfs_spinlock);
 176	list_del(&ld_type->pnfs_tblid);
 177	spin_unlock(&pnfs_spinlock);
 178}
 179EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
 180
 181/*
 182 * pNFS client layout cache
 183 */
 184
 185/* Need to hold i_lock if caller does not already hold reference */
 186void
 187get_layout_hdr(struct pnfs_layout_hdr *lo)
 188{
 189	atomic_inc(&lo->plh_refcount);
 190}
 191
 192static struct pnfs_layout_hdr *
 193pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags)
 194{
 195	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
 196	return ld->alloc_layout_hdr ? ld->alloc_layout_hdr(ino, gfp_flags) :
 197		kzalloc(sizeof(struct pnfs_layout_hdr), gfp_flags);
 198}
 199
 200static void
 201pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
 202{
 203	struct pnfs_layoutdriver_type *ld = NFS_SERVER(lo->plh_inode)->pnfs_curr_ld;
 
 
 
 
 
 
 
 
 
 204	put_rpccred(lo->plh_lc_cred);
 205	return ld->alloc_layout_hdr ? ld->free_layout_hdr(lo) : kfree(lo);
 206}
 207
 208static void
 209destroy_layout_hdr(struct pnfs_layout_hdr *lo)
 210{
 
 211	dprintk("%s: freeing layout cache %p\n", __func__, lo);
 212	BUG_ON(!list_empty(&lo->plh_layouts));
 213	NFS_I(lo->plh_inode)->layout = NULL;
 214	pnfs_free_layout_hdr(lo);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 215}
 216
 217static void
 218put_layout_hdr_locked(struct pnfs_layout_hdr *lo)
 
 219{
 220	if (atomic_dec_and_test(&lo->plh_refcount))
 221		destroy_layout_hdr(lo);
 
 
 
 
 
 
 222}
 223
 224void
 225put_layout_hdr(struct pnfs_layout_hdr *lo)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 226{
 227	struct inode *inode = lo->plh_inode;
 
 
 
 
 
 
 228
 229	if (atomic_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
 230		destroy_layout_hdr(lo);
 231		spin_unlock(&inode->i_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 232	}
 
 233}
 234
 235static void
 236init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg)
 
 
 237{
 238	INIT_LIST_HEAD(&lseg->pls_list);
 239	INIT_LIST_HEAD(&lseg->pls_lc_list);
 240	atomic_set(&lseg->pls_refcount, 1);
 241	smp_mb();
 242	set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
 243	lseg->pls_layout = lo;
 
 
 244}
 245
 246static void free_lseg(struct pnfs_layout_segment *lseg)
 247{
 248	struct inode *ino = lseg->pls_layout->plh_inode;
 249
 250	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
 251	/* Matched by get_layout_hdr in pnfs_insert_layout */
 252	put_layout_hdr(NFS_I(ino)->layout);
 253}
 254
 255static void
 256put_lseg_common(struct pnfs_layout_segment *lseg)
 
 257{
 258	struct inode *inode = lseg->pls_layout->plh_inode;
 259
 260	WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 261	list_del_init(&lseg->pls_list);
 262	if (list_empty(&lseg->pls_layout->plh_segs)) {
 263		set_bit(NFS_LAYOUT_DESTROYED, &lseg->pls_layout->plh_flags);
 264		/* Matched by initial refcount set in alloc_init_layout_hdr */
 265		put_layout_hdr_locked(lseg->pls_layout);
 
 
 
 
 
 
 266	}
 267	rpc_wake_up(&NFS_SERVER(inode)->roc_rpcwaitq);
 
 
 
 
 
 
 
 
 
 
 
 
 268}
 269
 270void
 271put_lseg(struct pnfs_layout_segment *lseg)
 272{
 
 273	struct inode *inode;
 274
 275	if (!lseg)
 276		return;
 277
 278	dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
 279		atomic_read(&lseg->pls_refcount),
 280		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 281	inode = lseg->pls_layout->plh_inode;
 282	if (atomic_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
 283		LIST_HEAD(free_me);
 284
 285		put_lseg_common(lseg);
 286		list_add(&lseg->pls_list, &free_me);
 
 
 
 
 
 
 
 
 
 
 287		spin_unlock(&inode->i_lock);
 288		pnfs_free_lseg_list(&free_me);
 
 289	}
 290}
 291EXPORT_SYMBOL_GPL(put_lseg);
 292
 293static inline u64
 294end_offset(u64 start, u64 len)
 295{
 296	u64 end;
 
 
 
 
 
 
 
 
 297
 298	end = start + len;
 299	return end >= start ? end : NFS4_MAX_UINT64;
 
 
 300}
 301
 302/* last octet in a range */
 303static inline u64
 304last_byte_offset(u64 start, u64 len)
 305{
 306	u64 end;
 
 
 
 307
 308	BUG_ON(!len);
 309	end = start + len;
 310	return end > start ? end - 1 : NFS4_MAX_UINT64;
 
 
 
 
 
 
 
 
 
 
 311}
 
 312
 313/*
 314 * is l2 fully contained in l1?
 315 *   start1                             end1
 316 *   [----------------------------------)
 317 *           start2           end2
 318 *           [----------------)
 319 */
 320static inline int
 321lo_seg_contained(struct pnfs_layout_range *l1,
 322		 struct pnfs_layout_range *l2)
 323{
 324	u64 start1 = l1->offset;
 325	u64 end1 = end_offset(start1, l1->length);
 326	u64 start2 = l2->offset;
 327	u64 end2 = end_offset(start2, l2->length);
 328
 329	return (start1 <= start2) && (end1 >= end2);
 330}
 331
 332/*
 333 * is l1 and l2 intersecting?
 334 *   start1                             end1
 335 *   [----------------------------------)
 336 *                              start2           end2
 337 *                              [----------------)
 338 */
 339static inline int
 340lo_seg_intersecting(struct pnfs_layout_range *l1,
 341		    struct pnfs_layout_range *l2)
 342{
 343	u64 start1 = l1->offset;
 344	u64 end1 = end_offset(start1, l1->length);
 345	u64 start2 = l2->offset;
 346	u64 end2 = end_offset(start2, l2->length);
 347
 348	return (end1 == NFS4_MAX_UINT64 || end1 > start2) &&
 349	       (end2 == NFS4_MAX_UINT64 || end2 > start1);
 350}
 351
 352static bool
 353should_free_lseg(struct pnfs_layout_range *lseg_range,
 354		 struct pnfs_layout_range *recall_range)
 355{
 356	return (recall_range->iomode == IOMODE_ANY ||
 357		lseg_range->iomode == recall_range->iomode) &&
 358	       lo_seg_intersecting(lseg_range, recall_range);
 359}
 360
 361/* Returns 1 if lseg is removed from list, 0 otherwise */
 362static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
 363			     struct list_head *tmp_list)
 364{
 365	int rv = 0;
 366
 367	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 368		/* Remove the reference keeping the lseg in the
 369		 * list.  It will now be removed when all
 370		 * outstanding io is finished.
 371		 */
 372		dprintk("%s: lseg %p ref %d\n", __func__, lseg,
 373			atomic_read(&lseg->pls_refcount));
 374		if (atomic_dec_and_test(&lseg->pls_refcount)) {
 375			put_lseg_common(lseg);
 376			list_add(&lseg->pls_list, tmp_list);
 377			rv = 1;
 378		}
 379	}
 380	return rv;
 381}
 382
 383/* Returns count of number of matching invalid lsegs remaining in list
 384 * after call.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 385 */
 386int
 387mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 388			    struct list_head *tmp_list,
 389			    struct pnfs_layout_range *recall_range)
 
 390{
 391	struct pnfs_layout_segment *lseg, *next;
 392	int invalid = 0, removed = 0;
 393
 394	dprintk("%s:Begin lo %p\n", __func__, lo);
 395
 396	if (list_empty(&lo->plh_segs)) {
 397		if (!test_and_set_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags))
 398			put_layout_hdr_locked(lo);
 399		return 0;
 400	}
 401	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 402		if (!recall_range ||
 403		    should_free_lseg(&lseg->pls_range, recall_range)) {
 404			dprintk("%s: freeing lseg %p iomode %d "
 405				"offset %llu length %llu\n", __func__,
 406				lseg, lseg->pls_range.iomode, lseg->pls_range.offset,
 407				lseg->pls_range.length);
 408			invalid++;
 409			removed += mark_lseg_invalid(lseg, tmp_list);
 410		}
 411	dprintk("%s:Return %i\n", __func__, invalid - removed);
 412	return invalid - removed;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 413}
 414
 415/* note free_me must contain lsegs from a single layout_hdr */
 416void
 417pnfs_free_lseg_list(struct list_head *free_me)
 418{
 419	struct pnfs_layout_segment *lseg, *tmp;
 420	struct pnfs_layout_hdr *lo;
 421
 422	if (list_empty(free_me))
 423		return;
 424
 425	lo = list_first_entry(free_me, struct pnfs_layout_segment,
 426			      pls_list)->pls_layout;
 427
 428	if (test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags)) {
 429		struct nfs_client *clp;
 430
 431		clp = NFS_SERVER(lo->plh_inode)->nfs_client;
 432		spin_lock(&clp->cl_lock);
 433		list_del_init(&lo->plh_layouts);
 434		spin_unlock(&clp->cl_lock);
 435	}
 436	list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
 437		list_del(&lseg->pls_list);
 438		free_lseg(lseg);
 439	}
 440}
 441
 442void
 443pnfs_destroy_layout(struct nfs_inode *nfsi)
 444{
 445	struct pnfs_layout_hdr *lo;
 446	LIST_HEAD(tmp_list);
 447
 448	spin_lock(&nfsi->vfs_inode.i_lock);
 449	lo = nfsi->layout;
 450	if (lo) {
 451		lo->plh_block_lgets++; /* permanently block new LAYOUTGETs */
 452		mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 453	}
 454	spin_unlock(&nfsi->vfs_inode.i_lock);
 455	pnfs_free_lseg_list(&tmp_list);
 456}
 457
 458/*
 459 * Called by the state manger to remove all layouts established under an
 460 * expired lease.
 461 */
 462void
 463pnfs_destroy_all_layouts(struct nfs_client *clp)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 464{
 465	struct nfs_server *server;
 466	struct pnfs_layout_hdr *lo;
 467	LIST_HEAD(tmp_list);
 
 
 468
 469	nfs4_deviceid_mark_client_invalid(clp);
 470	nfs4_deviceid_purge_client(clp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 471
 472	spin_lock(&clp->cl_lock);
 473	rcu_read_lock();
 
 474	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 475		if (!list_empty(&server->layouts))
 476			list_splice_init(&server->layouts, &tmp_list);
 
 
 
 
 477	}
 478	rcu_read_unlock();
 479	spin_unlock(&clp->cl_lock);
 480
 481	while (!list_empty(&tmp_list)) {
 482		lo = list_entry(tmp_list.next, struct pnfs_layout_hdr,
 483				plh_layouts);
 484		dprintk("%s freeing layout for inode %lu\n", __func__,
 485			lo->plh_inode->i_ino);
 486		list_del_init(&lo->plh_layouts);
 487		pnfs_destroy_layout(NFS_I(lo->plh_inode));
 
 
 
 
 
 
 
 
 
 
 
 
 
 488	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 489}
 490
 491/* update lo->plh_stateid with new if is more recent */
 492void
 493pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
 494			bool update_barrier)
 495{
 496	u32 oldseq, newseq;
 497
 498	oldseq = be32_to_cpu(lo->plh_stateid.stateid.seqid);
 499	newseq = be32_to_cpu(new->stateid.seqid);
 500	if ((int)(newseq - oldseq) > 0) {
 501		memcpy(&lo->plh_stateid, &new->stateid, sizeof(new->stateid));
 502		if (update_barrier) {
 503			u32 new_barrier = be32_to_cpu(new->stateid.seqid);
 504
 505			if ((int)(new_barrier - lo->plh_barrier))
 506				lo->plh_barrier = new_barrier;
 507		} else {
 508			/* Because of wraparound, we want to keep the barrier
 509			 * "close" to the current seqids.  It needs to be
 510			 * within 2**31 to count as "behind", so if it
 511			 * gets too near that limit, give us a litle leeway
 512			 * and bring it to within 2**30.
 513			 * NOTE - and yes, this is all unsigned arithmetic.
 514			 */
 515			if (unlikely((newseq - lo->plh_barrier) > (3 << 29)))
 516				lo->plh_barrier = newseq - (1 << 30);
 517		}
 518	}
 
 
 
 
 
 
 519}
 520
 521/* lget is set to 1 if called from inside send_layoutget call chain */
 522static bool
 523pnfs_layoutgets_blocked(struct pnfs_layout_hdr *lo, nfs4_stateid *stateid,
 524			int lget)
 525{
 526	if ((stateid) &&
 527	    (int)(lo->plh_barrier - be32_to_cpu(stateid->stateid.seqid)) >= 0)
 528		return true;
 529	return lo->plh_block_lgets ||
 530		test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags) ||
 531		test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
 532		(list_empty(&lo->plh_segs) &&
 533		 (atomic_read(&lo->plh_outstanding) > lget));
 534}
 535
 536int
 537pnfs_choose_layoutget_stateid(nfs4_stateid *dst, struct pnfs_layout_hdr *lo,
 538			      struct nfs4_state *open_state)
 539{
 540	int status = 0;
 541
 542	dprintk("--> %s\n", __func__);
 543	spin_lock(&lo->plh_inode->i_lock);
 544	if (pnfs_layoutgets_blocked(lo, NULL, 1)) {
 545		status = -EAGAIN;
 546	} else if (list_empty(&lo->plh_segs)) {
 547		int seq;
 548
 549		do {
 550			seq = read_seqbegin(&open_state->seqlock);
 551			memcpy(dst->data, open_state->stateid.data,
 552			       sizeof(open_state->stateid.data));
 553		} while (read_seqretry(&open_state->seqlock, seq));
 554	} else
 555		memcpy(dst->data, lo->plh_stateid.data, sizeof(lo->plh_stateid.data));
 556	spin_unlock(&lo->plh_inode->i_lock);
 557	dprintk("<-- %s\n", __func__);
 558	return status;
 559}
 560
 561/*
 562* Get layout from server.
 563*    for now, assume that whole file layouts are requested.
 564*    arg->offset: 0
 565*    arg->length: all ones
 566*/
 567static struct pnfs_layout_segment *
 568send_layoutget(struct pnfs_layout_hdr *lo,
 569	   struct nfs_open_context *ctx,
 570	   struct pnfs_layout_range *range,
 571	   gfp_t gfp_flags)
 
 572{
 573	struct inode *ino = lo->plh_inode;
 574	struct nfs_server *server = NFS_SERVER(ino);
 575	struct nfs4_layoutget *lgp;
 576	struct pnfs_layout_segment *lseg = NULL;
 577	struct page **pages = NULL;
 578	int i;
 579	u32 max_resp_sz, max_pages;
 580
 581	dprintk("--> %s\n", __func__);
 582
 583	BUG_ON(ctx == NULL);
 
 
 
 
 584	lgp = kzalloc(sizeof(*lgp), gfp_flags);
 585	if (lgp == NULL)
 586		return NULL;
 587
 588	/* allocate pages for xdr post processing */
 589	max_resp_sz = server->nfs_client->cl_session->fc_attrs.max_resp_sz;
 590	max_pages = max_resp_sz >> PAGE_SHIFT;
 591
 592	pages = kzalloc(max_pages * sizeof(struct page *), gfp_flags);
 593	if (!pages)
 594		goto out_err_free;
 595
 596	for (i = 0; i < max_pages; i++) {
 597		pages[i] = alloc_page(gfp_flags);
 598		if (!pages[i])
 599			goto out_err_free;
 600	}
 601
 602	lgp->args.minlength = PAGE_CACHE_SIZE;
 603	if (lgp->args.minlength > range->length)
 604		lgp->args.minlength = range->length;
 
 
 
 
 
 
 605	lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
 606	lgp->args.range = *range;
 607	lgp->args.type = server->pnfs_curr_ld->id;
 608	lgp->args.inode = ino;
 609	lgp->args.ctx = get_nfs_open_context(ctx);
 610	lgp->args.layout.pages = pages;
 611	lgp->args.layout.pglen = max_pages * PAGE_SIZE;
 612	lgp->lsegpp = &lseg;
 613	lgp->gfp_flags = gfp_flags;
 
 614
 615	/* Synchronously retrieve layout information from server and
 616	 * store in lseg.
 617	 */
 618	nfs4_proc_layoutget(lgp);
 619	if (!lseg) {
 620		/* remember that LAYOUTGET failed and suspend trying */
 621		set_bit(lo_fail_bit(range->iomode), &lo->plh_flags);
 
 
 
 
 
 
 
 
 622	}
 
 623
 624	/* free xdr pages */
 625	for (i = 0; i < max_pages; i++)
 626		__free_page(pages[i]);
 627	kfree(pages);
 
 
 
 628
 629	return lseg;
 
 
 
 
 
 630
 631out_err_free:
 632	/* free any allocated xdr pages, lgp as it's not used */
 633	if (pages) {
 634		for (i = 0; i < max_pages; i++) {
 635			if (!pages[i])
 636				break;
 637			__free_page(pages[i]);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 638		}
 639		kfree(pages);
 
 
 
 640	}
 641	kfree(lgp);
 642	return NULL;
 
 
 
 643}
 644
 645/* Initiates a LAYOUTRETURN(FILE) */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 646int
 647_pnfs_return_layout(struct inode *ino)
 648{
 649	struct pnfs_layout_hdr *lo = NULL;
 650	struct nfs_inode *nfsi = NFS_I(ino);
 651	LIST_HEAD(tmp_list);
 652	struct nfs4_layoutreturn *lrp;
 653	nfs4_stateid stateid;
 654	int status = 0;
 
 655
 656	dprintk("--> %s\n", __func__);
 657
 658	spin_lock(&ino->i_lock);
 659	lo = nfsi->layout;
 660	if (!lo) {
 661		spin_unlock(&ino->i_lock);
 662		dprintk("%s: no layout to return\n", __func__);
 663		return status;
 664	}
 665	stateid = nfsi->layout->plh_stateid;
 666	/* Reference matched in nfs4_layoutreturn_release */
 667	get_layout_hdr(lo);
 668	mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
 669	lo->plh_block_lgets++;
 670	spin_unlock(&ino->i_lock);
 671	pnfs_free_lseg_list(&tmp_list);
 672
 673	WARN_ON(test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags));
 674
 675	lrp = kzalloc(sizeof(*lrp), GFP_KERNEL);
 676	if (unlikely(lrp == NULL)) {
 677		status = -ENOMEM;
 678		set_bit(NFS_LAYOUT_RW_FAILED, &lo->plh_flags);
 679		set_bit(NFS_LAYOUT_RO_FAILED, &lo->plh_flags);
 680		put_layout_hdr(lo);
 681		goto out;
 
 
 
 
 682	}
 683
 684	lrp->args.stateid = stateid;
 685	lrp->args.layout_type = NFS_SERVER(ino)->pnfs_curr_ld->id;
 686	lrp->args.inode = ino;
 687	lrp->args.layout = lo;
 688	lrp->clp = NFS_SERVER(ino)->nfs_client;
 
 689
 690	status = nfs4_proc_layoutreturn(lrp);
 
 
 
 
 
 
 691out:
 692	dprintk("<-- %s status: %d\n", __func__, status);
 693	return status;
 694}
 
 695
 696bool pnfs_roc(struct inode *ino)
 
 697{
 698	struct pnfs_layout_hdr *lo;
 699	struct pnfs_layout_segment *lseg, *tmp;
 700	LIST_HEAD(tmp_list);
 701	bool found = false;
 702
 703	spin_lock(&ino->i_lock);
 704	lo = NFS_I(ino)->layout;
 705	if (!lo || !test_and_clear_bit(NFS_LAYOUT_ROC, &lo->plh_flags) ||
 706	    test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags))
 707		goto out_nolayout;
 708	list_for_each_entry_safe(lseg, tmp, &lo->plh_segs, pls_list)
 709		if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
 710			mark_lseg_invalid(lseg, &tmp_list);
 711			found = true;
 712		}
 713	if (!found)
 714		goto out_nolayout;
 715	lo->plh_block_lgets++;
 716	get_layout_hdr(lo); /* matched in pnfs_roc_release */
 717	spin_unlock(&ino->i_lock);
 718	pnfs_free_lseg_list(&tmp_list);
 719	return true;
 720
 721out_nolayout:
 722	spin_unlock(&ino->i_lock);
 723	return false;
 
 
 724}
 725
 726void pnfs_roc_release(struct inode *ino)
 
 
 
 727{
 
 
 
 728	struct pnfs_layout_hdr *lo;
 
 
 
 
 
 729
 
 
 
 730	spin_lock(&ino->i_lock);
 731	lo = NFS_I(ino)->layout;
 732	lo->plh_block_lgets--;
 733	put_layout_hdr_locked(lo);
 734	spin_unlock(&ino->i_lock);
 735}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 736
 737void pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
 738{
 739	struct pnfs_layout_hdr *lo;
 740
 741	spin_lock(&ino->i_lock);
 742	lo = NFS_I(ino)->layout;
 743	if ((int)(barrier - lo->plh_barrier) > 0)
 744		lo->plh_barrier = barrier;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 745	spin_unlock(&ino->i_lock);
 
 
 
 
 
 
 
 
 
 
 746}
 747
 748bool pnfs_roc_drain(struct inode *ino, u32 *barrier)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 749{
 750	struct nfs_inode *nfsi = NFS_I(ino);
 751	struct pnfs_layout_segment *lseg;
 752	bool found = false;
 753
 754	spin_lock(&ino->i_lock);
 755	list_for_each_entry(lseg, &nfsi->layout->plh_segs, pls_list)
 756		if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
 757			found = true;
 758			break;
 759		}
 760	if (!found) {
 761		struct pnfs_layout_hdr *lo = nfsi->layout;
 762		u32 current_seqid = be32_to_cpu(lo->plh_stateid.stateid.seqid);
 763
 764		/* Since close does not return a layout stateid for use as
 765		 * a barrier, we choose the worst-case barrier.
 766		 */
 767		*barrier = current_seqid + atomic_read(&lo->plh_outstanding);
 768	}
 769	spin_unlock(&ino->i_lock);
 770	return found;
 771}
 772
 773/*
 774 * Compare two layout segments for sorting into layout cache.
 775 * We want to preferentially return RW over RO layouts, so ensure those
 776 * are seen first.
 777 */
 778static s64
 779cmp_layout(struct pnfs_layout_range *l1,
 780	   struct pnfs_layout_range *l2)
 781{
 782	s64 d;
 783
 784	/* high offset > low offset */
 785	d = l1->offset - l2->offset;
 786	if (d)
 787		return d;
 788
 789	/* short length > long length */
 790	d = l2->length - l1->length;
 791	if (d)
 792		return d;
 793
 794	/* read > read/write */
 795	return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
 796}
 797
 798static void
 799pnfs_insert_layout(struct pnfs_layout_hdr *lo,
 800		   struct pnfs_layout_segment *lseg)
 
 
 
 
 
 
 
 801{
 802	struct pnfs_layout_segment *lp;
 
 
 
 
 
 
 
 
 
 
 
 
 803
 804	dprintk("%s:Begin\n", __func__);
 805
 806	assert_spin_locked(&lo->plh_inode->i_lock);
 807	list_for_each_entry(lp, &lo->plh_segs, pls_list) {
 808		if (cmp_layout(&lseg->pls_range, &lp->pls_range) > 0)
 
 
 
 
 
 809			continue;
 810		list_add_tail(&lseg->pls_list, &lp->pls_list);
 811		dprintk("%s: inserted lseg %p "
 812			"iomode %d offset %llu length %llu before "
 813			"lp %p iomode %d offset %llu length %llu\n",
 814			__func__, lseg, lseg->pls_range.iomode,
 815			lseg->pls_range.offset, lseg->pls_range.length,
 816			lp, lp->pls_range.iomode, lp->pls_range.offset,
 817			lp->pls_range.length);
 818		goto out;
 819	}
 820	list_add_tail(&lseg->pls_list, &lo->plh_segs);
 821	dprintk("%s: inserted lseg %p "
 822		"iomode %d offset %llu length %llu at tail\n",
 823		__func__, lseg, lseg->pls_range.iomode,
 824		lseg->pls_range.offset, lseg->pls_range.length);
 825out:
 826	get_layout_hdr(lo);
 827
 828	dprintk("%s:Return\n", __func__);
 829}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 830
 831static struct pnfs_layout_hdr *
 832alloc_init_layout_hdr(struct inode *ino,
 833		      struct nfs_open_context *ctx,
 834		      gfp_t gfp_flags)
 835{
 836	struct pnfs_layout_hdr *lo;
 837
 838	lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
 839	if (!lo)
 840		return NULL;
 841	atomic_set(&lo->plh_refcount, 1);
 842	INIT_LIST_HEAD(&lo->plh_layouts);
 843	INIT_LIST_HEAD(&lo->plh_segs);
 844	INIT_LIST_HEAD(&lo->plh_bulk_recall);
 
 845	lo->plh_inode = ino;
 846	lo->plh_lc_cred = get_rpccred(ctx->state->owner->so_cred);
 
 847	return lo;
 848}
 849
 850static struct pnfs_layout_hdr *
 851pnfs_find_alloc_layout(struct inode *ino,
 852		       struct nfs_open_context *ctx,
 853		       gfp_t gfp_flags)
 
 
 854{
 855	struct nfs_inode *nfsi = NFS_I(ino);
 856	struct pnfs_layout_hdr *new = NULL;
 857
 858	dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
 859
 860	assert_spin_locked(&ino->i_lock);
 861	if (nfsi->layout) {
 862		if (test_bit(NFS_LAYOUT_DESTROYED, &nfsi->layout->plh_flags))
 863			return NULL;
 864		else
 865			return nfsi->layout;
 866	}
 867	spin_unlock(&ino->i_lock);
 868	new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
 869	spin_lock(&ino->i_lock);
 870
 871	if (likely(nfsi->layout == NULL))	/* Won the race? */
 872		nfsi->layout = new;
 873	else
 
 874		pnfs_free_layout_hdr(new);
 
 
 875	return nfsi->layout;
 876}
 877
 878/*
 879 * iomode matching rules:
 880 * iomode	lseg	match
 881 * -----	-----	-----
 882 * ANY		READ	true
 883 * ANY		RW	true
 884 * RW		READ	false
 885 * RW		RW	true
 886 * READ		READ	true
 887 * READ		RW	true
 
 
 888 */
 889static int
 890is_matching_lseg(struct pnfs_layout_range *ls_range,
 891		 struct pnfs_layout_range *range)
 
 892{
 893	struct pnfs_layout_range range1;
 894
 895	if ((range->iomode == IOMODE_RW &&
 896	     ls_range->iomode != IOMODE_RW) ||
 897	    !lo_seg_intersecting(ls_range, range))
 
 
 898		return 0;
 899
 900	/* range1 covers only the first byte in the range */
 901	range1 = *range;
 902	range1.length = 1;
 903	return lo_seg_contained(ls_range, &range1);
 904}
 905
 906/*
 907 * lookup range in layout
 908 */
 909static struct pnfs_layout_segment *
 910pnfs_find_lseg(struct pnfs_layout_hdr *lo,
 911		struct pnfs_layout_range *range)
 
 912{
 913	struct pnfs_layout_segment *lseg, *ret = NULL;
 914
 915	dprintk("%s:Begin\n", __func__);
 916
 917	assert_spin_locked(&lo->plh_inode->i_lock);
 918	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
 919		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
 920		    is_matching_lseg(&lseg->pls_range, range)) {
 921			ret = get_lseg(lseg);
 
 
 922			break;
 923		}
 924		if (lseg->pls_range.offset > range->offset)
 925			break;
 926	}
 927
 928	dprintk("%s:Return lseg %p ref %d\n",
 929		__func__, ret, ret ? atomic_read(&ret->pls_refcount) : 0);
 930	return ret;
 931}
 932
 933/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 934 * Layout segment is retreived from the server if not cached.
 935 * The appropriate layout segment is referenced and returned to the caller.
 936 */
 937struct pnfs_layout_segment *
 938pnfs_update_layout(struct inode *ino,
 939		   struct nfs_open_context *ctx,
 940		   loff_t pos,
 941		   u64 count,
 942		   enum pnfs_iomode iomode,
 
 943		   gfp_t gfp_flags)
 944{
 945	struct pnfs_layout_range arg = {
 946		.iomode = iomode,
 947		.offset = pos,
 948		.length = count,
 949	};
 950	unsigned pg_offset;
 951	struct nfs_inode *nfsi = NFS_I(ino);
 952	struct nfs_server *server = NFS_SERVER(ino);
 953	struct nfs_client *clp = server->nfs_client;
 954	struct pnfs_layout_hdr *lo;
 955	struct pnfs_layout_segment *lseg = NULL;
 956	bool first = false;
 
 
 
 
 
 
 
 
 
 957
 958	if (!pnfs_enabled_sb(NFS_SERVER(ino)))
 959		return NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 960	spin_lock(&ino->i_lock);
 961	lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
 962	if (lo == NULL) {
 963		dprintk("%s ERROR: can't get pnfs_layout_hdr\n", __func__);
 964		goto out_unlock;
 
 
 965	}
 966
 967	/* Do we even need to bother with this? */
 968	if (test_bit(NFS4CLNT_LAYOUTRECALL, &clp->cl_state) ||
 969	    test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
 
 970		dprintk("%s matches recall, use MDS\n", __func__);
 971		goto out_unlock;
 972	}
 973
 974	/* if LAYOUTGET already failed once we don't try again */
 975	if (test_bit(lo_fail_bit(iomode), &nfsi->layout->plh_flags))
 
 
 976		goto out_unlock;
 
 977
 978	/* Check to see if the layout for the given range already exists */
 979	lseg = pnfs_find_lseg(lo, &arg);
 980	if (lseg)
 
 981		goto out_unlock;
 
 982
 983	if (pnfs_layoutgets_blocked(lo, NULL, 0))
 
 
 984		goto out_unlock;
 985	atomic_inc(&lo->plh_outstanding);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 986
 987	get_layout_hdr(lo);
 988	if (list_empty(&lo->plh_segs))
 989		first = true;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 990	spin_unlock(&ino->i_lock);
 991	if (first) {
 
 992		/* The lo must be on the clp list if there is any
 993		 * chance of a CB_LAYOUTRECALL(FILE) coming in.
 994		 */
 995		spin_lock(&clp->cl_lock);
 996		BUG_ON(!list_empty(&lo->plh_layouts));
 997		list_add_tail(&lo->plh_layouts, &server->layouts);
 998		spin_unlock(&clp->cl_lock);
 999	}
1000
1001	pg_offset = arg.offset & ~PAGE_CACHE_MASK;
1002	if (pg_offset) {
1003		arg.offset -= pg_offset;
1004		arg.length += pg_offset;
1005	}
1006	if (arg.length != NFS4_MAX_UINT64)
1007		arg.length = PAGE_CACHE_ALIGN(arg.length);
1008
1009	lseg = send_layoutget(lo, ctx, &arg, gfp_flags);
1010	if (!lseg && first) {
1011		spin_lock(&clp->cl_lock);
1012		list_del_init(&lo->plh_layouts);
1013		spin_unlock(&clp->cl_lock);
1014	}
1015	atomic_dec(&lo->plh_outstanding);
1016	put_layout_hdr(lo);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1017out:
1018	dprintk("%s end, state 0x%lx lseg %p\n", __func__,
1019		nfsi->layout ? nfsi->layout->plh_flags : -1, lseg);
 
 
 
 
 
 
1020	return lseg;
1021out_unlock:
1022	spin_unlock(&ino->i_lock);
1023	goto out;
1024}
1025EXPORT_SYMBOL_GPL(pnfs_update_layout);
1026
1027int
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1028pnfs_layout_process(struct nfs4_layoutget *lgp)
1029{
1030	struct pnfs_layout_hdr *lo = NFS_I(lgp->args.inode)->layout;
1031	struct nfs4_layoutget_res *res = &lgp->res;
1032	struct pnfs_layout_segment *lseg;
1033	struct inode *ino = lo->plh_inode;
1034	struct nfs_client *clp = NFS_SERVER(ino)->nfs_client;
1035	int status = 0;
 
 
1036
1037	/* Inject layout blob into I/O device driver */
1038	lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
1039	if (!lseg || IS_ERR(lseg)) {
1040		if (!lseg)
1041			status = -ENOMEM;
1042		else
1043			status = PTR_ERR(lseg);
1044		dprintk("%s: Could not allocate layout: error %d\n",
1045		       __func__, status);
1046		goto out;
1047	}
1048
 
 
1049	spin_lock(&ino->i_lock);
1050	if (test_bit(NFS4CLNT_LAYOUTRECALL, &clp->cl_state) ||
1051	    test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1052		dprintk("%s forget reply due to recall\n", __func__);
1053		goto out_forget_reply;
1054	}
1055
1056	if (pnfs_layoutgets_blocked(lo, &res->stateid, 1)) {
1057		dprintk("%s forget reply due to state\n", __func__);
1058		goto out_forget_reply;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1059	}
1060	init_lseg(lo, lseg);
1061	lseg->pls_range = res->range;
1062	*lgp->lsegpp = get_lseg(lseg);
1063	pnfs_insert_layout(lo, lseg);
1064
1065	if (res->return_on_close) {
 
 
 
 
1066		set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
1067		set_bit(NFS_LAYOUT_ROC, &lo->plh_flags);
1068	}
1069
1070	/* Done processing layoutget. Set the layout stateid */
1071	pnfs_set_layout_stateid(lo, &res->stateid, false);
1072	spin_unlock(&ino->i_lock);
1073out:
1074	return status;
1075
1076out_forget_reply:
1077	spin_unlock(&ino->i_lock);
1078	lseg->pls_layout = lo;
1079	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
1080	goto out;
1081}
1082
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1083void
1084pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
1085{
1086	BUG_ON(pgio->pg_lseg != NULL);
 
 
 
 
 
 
1087
1088	pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
1089					   req->wb_context,
1090					   req_offset(req),
1091					   req->wb_bytes,
1092					   IOMODE_READ,
1093					   GFP_KERNEL);
 
 
 
 
 
 
 
1094	/* If no lseg, fall back to read through mds */
1095	if (pgio->pg_lseg == NULL)
1096		nfs_pageio_reset_read_mds(pgio);
1097
1098}
1099EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);
1100
1101void
1102pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
 
1103{
1104	BUG_ON(pgio->pg_lseg != NULL);
1105
1106	pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
1107					   req->wb_context,
1108					   req_offset(req),
1109					   req->wb_bytes,
1110					   IOMODE_RW,
1111					   GFP_NOFS);
 
 
 
 
 
 
1112	/* If no lseg, fall back to write through mds */
1113	if (pgio->pg_lseg == NULL)
1114		nfs_pageio_reset_write_mds(pgio);
1115}
1116EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
1117
1118bool
1119pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode)
1120{
1121	struct nfs_server *server = NFS_SERVER(inode);
1122	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
1123
1124	if (ld == NULL)
1125		return false;
1126	nfs_pageio_init(pgio, inode, ld->pg_read_ops, server->rsize, 0);
1127	return true;
1128}
 
1129
1130bool
1131pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode, int ioflags)
 
 
 
 
 
1132{
1133	struct nfs_server *server = NFS_SERVER(inode);
1134	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
1135
1136	if (ld == NULL)
1137		return false;
1138	nfs_pageio_init(pgio, inode, ld->pg_write_ops, server->wsize, ioflags);
1139	return true;
1140}
1141
1142bool
1143pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
1144		     struct nfs_page *req)
1145{
1146	if (pgio->pg_lseg == NULL)
1147		return nfs_generic_pg_test(pgio, prev, req);
1148
1149	/*
1150	 * Test if a nfs_page is fully contained in the pnfs_layout_range.
1151	 * Note that this test makes several assumptions:
1152	 * - that the previous nfs_page in the struct nfs_pageio_descriptor
1153	 *   is known to lie within the range.
1154	 *   - that the nfs_page being tested is known to be contiguous with the
1155	 *   previous nfs_page.
1156	 *   - Layout ranges are page aligned, so we only have to test the
1157	 *   start offset of the request.
1158	 *
1159	 * Please also note that 'end_offset' is actually the offset of the
1160	 * first byte that lies outside the pnfs_layout_range. FIXME?
1161	 *
1162	 */
1163	return req_offset(req) < end_offset(pgio->pg_lseg->pls_range.offset,
1164					 pgio->pg_lseg->pls_range.length);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1165}
1166EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
1167
1168/*
1169 * Called by non rpc-based layout drivers
1170 */
1171int
1172pnfs_ld_write_done(struct nfs_write_data *data)
1173{
1174	int status;
1175
1176	if (!data->pnfs_error) {
1177		pnfs_set_layoutcommit(data);
1178		data->mds_ops->rpc_call_done(&data->task, data);
1179		data->mds_ops->rpc_release(data);
1180		return 0;
 
 
 
 
 
 
 
 
 
 
1181	}
 
 
 
1182
1183	dprintk("%s: pnfs_error=%d, retry via MDS\n", __func__,
1184		data->pnfs_error);
1185	status = nfs_initiate_write(data, NFS_CLIENT(data->inode),
1186				    data->mds_ops, NFS_FILE_SYNC);
1187	return status ? : -EAGAIN;
 
 
 
 
 
 
 
 
 
1188}
1189EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
1190
1191static void
1192pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
1193		struct nfs_write_data *data)
1194{
1195	list_splice_tail_init(&data->pages, &desc->pg_list);
1196	if (data->req && list_empty(&data->req->wb_list))
1197		nfs_list_add_request(data->req, &desc->pg_list);
1198	nfs_pageio_reset_write_mds(desc);
1199	desc->pg_recoalesce = 1;
1200	nfs_writedata_release(data);
 
 
 
1201}
1202
1203static enum pnfs_try_status
1204pnfs_try_to_write_data(struct nfs_write_data *wdata,
1205			const struct rpc_call_ops *call_ops,
1206			struct pnfs_layout_segment *lseg,
1207			int how)
1208{
1209	struct inode *inode = wdata->inode;
1210	enum pnfs_try_status trypnfs;
1211	struct nfs_server *nfss = NFS_SERVER(inode);
1212
1213	wdata->mds_ops = call_ops;
1214	wdata->lseg = get_lseg(lseg);
1215
1216	dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
1217		inode->i_ino, wdata->args.count, wdata->args.offset, how);
1218
1219	trypnfs = nfss->pnfs_curr_ld->write_pagelist(wdata, how);
1220	if (trypnfs == PNFS_NOT_ATTEMPTED) {
1221		put_lseg(wdata->lseg);
1222		wdata->lseg = NULL;
1223	} else
1224		nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
1225
1226	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
1227	return trypnfs;
1228}
1229
1230static void
1231pnfs_do_multiple_writes(struct nfs_pageio_descriptor *desc, struct list_head *head, int how)
 
1232{
1233	struct nfs_write_data *data;
1234	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
1235	struct pnfs_layout_segment *lseg = desc->pg_lseg;
 
1236
1237	desc->pg_lseg = NULL;
1238	while (!list_empty(head)) {
1239		enum pnfs_try_status trypnfs;
1240
1241		data = list_entry(head->next, struct nfs_write_data, list);
1242		list_del_init(&data->list);
1243
1244		trypnfs = pnfs_try_to_write_data(data, call_ops, lseg, how);
1245		if (trypnfs == PNFS_NOT_ATTEMPTED)
1246			pnfs_write_through_mds(desc, data);
1247	}
1248	put_lseg(lseg);
1249}
1250
1251int
1252pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
1253{
1254	LIST_HEAD(head);
1255	int ret;
1256
1257	ret = nfs_generic_flush(desc, &head);
1258	if (ret != 0) {
1259		put_lseg(desc->pg_lseg);
1260		desc->pg_lseg = NULL;
1261		return ret;
1262	}
1263	pnfs_do_multiple_writes(desc, &head, desc->pg_ioflags);
1264	return 0;
 
 
 
 
 
1265}
1266EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
1267
1268/*
1269 * Called by non rpc-based layout drivers
1270 */
1271int
1272pnfs_ld_read_done(struct nfs_read_data *data)
1273{
1274	int status;
1275
1276	if (!data->pnfs_error) {
1277		__nfs4_read_done_cb(data);
1278		data->mds_ops->rpc_call_done(&data->task, data);
1279		data->mds_ops->rpc_release(data);
1280		return 0;
 
 
 
 
 
 
 
1281	}
 
 
 
1282
1283	dprintk("%s: pnfs_error=%d, retry via MDS\n", __func__,
1284		data->pnfs_error);
1285	status = nfs_initiate_read(data, NFS_CLIENT(data->inode),
1286				   data->mds_ops);
1287	return status ? : -EAGAIN;
 
 
 
 
 
 
1288}
1289EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
1290
1291static void
1292pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
1293		struct nfs_read_data *data)
1294{
1295	list_splice_tail_init(&data->pages, &desc->pg_list);
1296	if (data->req && list_empty(&data->req->wb_list))
1297		nfs_list_add_request(data->req, &desc->pg_list);
1298	nfs_pageio_reset_read_mds(desc);
1299	desc->pg_recoalesce = 1;
1300	nfs_readdata_release(data);
 
 
 
1301}
1302
1303/*
1304 * Call the appropriate parallel I/O subsystem read function.
1305 */
1306static enum pnfs_try_status
1307pnfs_try_to_read_data(struct nfs_read_data *rdata,
1308		       const struct rpc_call_ops *call_ops,
1309		       struct pnfs_layout_segment *lseg)
1310{
1311	struct inode *inode = rdata->inode;
1312	struct nfs_server *nfss = NFS_SERVER(inode);
1313	enum pnfs_try_status trypnfs;
1314
1315	rdata->mds_ops = call_ops;
1316	rdata->lseg = get_lseg(lseg);
1317
1318	dprintk("%s: Reading ino:%lu %u@%llu\n",
1319		__func__, inode->i_ino, rdata->args.count, rdata->args.offset);
1320
1321	trypnfs = nfss->pnfs_curr_ld->read_pagelist(rdata);
1322	if (trypnfs == PNFS_NOT_ATTEMPTED) {
1323		put_lseg(rdata->lseg);
1324		rdata->lseg = NULL;
1325	} else {
1326		nfs_inc_stats(inode, NFSIOS_PNFS_READ);
1327	}
1328	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
1329	return trypnfs;
1330}
1331
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1332static void
1333pnfs_do_multiple_reads(struct nfs_pageio_descriptor *desc, struct list_head *head)
1334{
1335	struct nfs_read_data *data;
1336	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
1337	struct pnfs_layout_segment *lseg = desc->pg_lseg;
 
1338
1339	desc->pg_lseg = NULL;
1340	while (!list_empty(head)) {
1341		enum pnfs_try_status trypnfs;
1342
1343		data = list_entry(head->next, struct nfs_read_data, list);
1344		list_del_init(&data->list);
1345
1346		trypnfs = pnfs_try_to_read_data(data, call_ops, lseg);
1347		if (trypnfs == PNFS_NOT_ATTEMPTED)
1348			pnfs_read_through_mds(desc, data);
1349	}
1350	put_lseg(lseg);
1351}
1352
1353int
1354pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
1355{
1356	LIST_HEAD(head);
1357	int ret;
1358
1359	ret = nfs_generic_pagein(desc, &head);
1360	if (ret != 0) {
1361		put_lseg(desc->pg_lseg);
1362		desc->pg_lseg = NULL;
1363		return ret;
1364	}
1365	pnfs_do_multiple_reads(desc, &head);
1366	return 0;
 
 
 
1367}
1368EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
1369
 
 
 
 
 
 
 
 
 
1370/*
1371 * There can be multiple RW segments.
1372 */
1373static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
1374{
1375	struct pnfs_layout_segment *lseg;
1376
1377	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
1378		if (lseg->pls_range.iomode == IOMODE_RW &&
1379		    test_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
1380			list_add(&lseg->pls_lc_list, listp);
1381	}
1382}
1383
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1384void
1385pnfs_set_layoutcommit(struct nfs_write_data *wdata)
 
1386{
1387	struct nfs_inode *nfsi = NFS_I(wdata->inode);
1388	loff_t end_pos = wdata->mds_offset + wdata->res.count;
1389	bool mark_as_dirty = false;
1390
1391	spin_lock(&nfsi->vfs_inode.i_lock);
1392	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
 
1393		mark_as_dirty = true;
1394		dprintk("%s: Set layoutcommit for inode %lu ",
1395			__func__, wdata->inode->i_ino);
1396	}
1397	if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &wdata->lseg->pls_flags)) {
 
1398		/* references matched in nfs4_layoutcommit_release */
1399		get_lseg(wdata->lseg);
1400	}
1401	if (end_pos > nfsi->layout->plh_lwb)
1402		nfsi->layout->plh_lwb = end_pos;
1403	spin_unlock(&nfsi->vfs_inode.i_lock);
1404	dprintk("%s: lseg %p end_pos %llu\n",
1405		__func__, wdata->lseg, nfsi->layout->plh_lwb);
1406
1407	/* if pnfs_layoutcommit_inode() runs between inode locks, the next one
1408	 * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */
1409	if (mark_as_dirty)
1410		mark_inode_dirty_sync(wdata->inode);
1411}
1412EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
1413
1414void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data)
1415{
1416	struct nfs_server *nfss = NFS_SERVER(data->args.inode);
1417
1418	if (nfss->pnfs_curr_ld->cleanup_layoutcommit)
1419		nfss->pnfs_curr_ld->cleanup_layoutcommit(data);
 
1420}
1421
1422/*
1423 * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
1424 * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
1425 * data to disk to allow the server to recover the data if it crashes.
1426 * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
1427 * is off, and a COMMIT is sent to a data server, or
1428 * if WRITEs to a data server return NFS_DATA_SYNC.
1429 */
1430int
1431pnfs_layoutcommit_inode(struct inode *inode, bool sync)
1432{
 
1433	struct nfs4_layoutcommit_data *data;
1434	struct nfs_inode *nfsi = NFS_I(inode);
1435	loff_t end_pos;
1436	int status = 0;
 
 
 
1437
1438	dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
1439
1440	if (!test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
1441		return 0;
 
 
 
 
 
 
 
 
 
1442
 
1443	/* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
1444	data = kzalloc(sizeof(*data), GFP_NOFS);
1445	if (!data) {
1446		mark_inode_dirty_sync(inode);
1447		status = -ENOMEM;
1448		goto out;
1449	}
1450
1451	INIT_LIST_HEAD(&data->lseg_list);
1452	spin_lock(&inode->i_lock);
1453	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
1454		spin_unlock(&inode->i_lock);
1455		kfree(data);
1456		goto out;
1457	}
1458
 
1459	pnfs_list_write_lseg(inode, &data->lseg_list);
1460
1461	end_pos = nfsi->layout->plh_lwb;
1462	nfsi->layout->plh_lwb = 0;
1463
1464	memcpy(&data->args.stateid.data, nfsi->layout->plh_stateid.data,
1465		sizeof(nfsi->layout->plh_stateid.data));
1466	spin_unlock(&inode->i_lock);
1467
1468	data->args.inode = inode;
1469	data->cred = get_rpccred(nfsi->layout->plh_lc_cred);
1470	nfs_fattr_init(&data->fattr);
1471	data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
1472	data->res.fattr = &data->fattr;
1473	data->args.lastbytewritten = end_pos - 1;
 
 
 
1474	data->res.server = NFS_SERVER(inode);
1475
 
 
 
 
 
 
 
 
 
 
 
 
 
1476	status = nfs4_proc_layoutcommit(data, sync);
1477out:
 
 
1478	dprintk("<-- %s status %d\n", __func__, status);
1479	return status;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1480}
v4.10.11
   1/*
   2 *  pNFS functions to call and manage layout drivers.
   3 *
   4 *  Copyright (c) 2002 [year of first publication]
   5 *  The Regents of the University of Michigan
   6 *  All Rights Reserved
   7 *
   8 *  Dean Hildebrand <dhildebz@umich.edu>
   9 *
  10 *  Permission is granted to use, copy, create derivative works, and
  11 *  redistribute this software and such derivative works for any purpose,
  12 *  so long as the name of the University of Michigan is not used in
  13 *  any advertising or publicity pertaining to the use or distribution
  14 *  of this software without specific, written prior authorization. If
  15 *  the above copyright notice or any other identification of the
  16 *  University of Michigan is included in any copy of any portion of
  17 *  this software, then the disclaimer below must also be included.
  18 *
  19 *  This software is provided as is, without representation or warranty
  20 *  of any kind either express or implied, including without limitation
  21 *  the implied warranties of merchantability, fitness for a particular
  22 *  purpose, or noninfringement.  The Regents of the University of
  23 *  Michigan shall not be liable for any damages, including special,
  24 *  indirect, incidental, or consequential damages, with respect to any
  25 *  claim arising out of or in connection with the use of the software,
  26 *  even if it has been or is hereafter advised of the possibility of
  27 *  such damages.
  28 */
  29
  30#include <linux/nfs_fs.h>
  31#include <linux/nfs_page.h>
  32#include <linux/module.h>
  33#include <linux/sort.h>
  34#include "internal.h"
  35#include "pnfs.h"
  36#include "iostat.h"
  37#include "nfs4trace.h"
  38#include "delegation.h"
  39#include "nfs42.h"
  40
  41#define NFSDBG_FACILITY		NFSDBG_PNFS
  42#define PNFS_LAYOUTGET_RETRY_TIMEOUT (120*HZ)
  43
  44/* Locking:
  45 *
  46 * pnfs_spinlock:
  47 *      protects pnfs_modules_tbl.
  48 */
  49static DEFINE_SPINLOCK(pnfs_spinlock);
  50
  51/*
  52 * pnfs_modules_tbl holds all pnfs modules
  53 */
  54static LIST_HEAD(pnfs_modules_tbl);
  55
  56static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo);
  57static void pnfs_free_returned_lsegs(struct pnfs_layout_hdr *lo,
  58		struct list_head *free_me,
  59		const struct pnfs_layout_range *range,
  60		u32 seq);
  61static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
  62		                struct list_head *tmp_list);
  63
  64/* Return the registered pnfs layout driver module matching given id */
  65static struct pnfs_layoutdriver_type *
  66find_pnfs_driver_locked(u32 id)
  67{
  68	struct pnfs_layoutdriver_type *local;
  69
  70	list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid)
  71		if (local->id == id)
  72			goto out;
  73	local = NULL;
  74out:
  75	dprintk("%s: Searching for id %u, found %p\n", __func__, id, local);
  76	return local;
  77}
  78
  79static struct pnfs_layoutdriver_type *
  80find_pnfs_driver(u32 id)
  81{
  82	struct pnfs_layoutdriver_type *local;
  83
  84	spin_lock(&pnfs_spinlock);
  85	local = find_pnfs_driver_locked(id);
  86	if (local != NULL && !try_module_get(local->owner)) {
  87		dprintk("%s: Could not grab reference on module\n", __func__);
  88		local = NULL;
  89	}
  90	spin_unlock(&pnfs_spinlock);
  91	return local;
  92}
  93
  94void
  95unset_pnfs_layoutdriver(struct nfs_server *nfss)
  96{
  97	if (nfss->pnfs_curr_ld) {
  98		if (nfss->pnfs_curr_ld->clear_layoutdriver)
  99			nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
 100		/* Decrement the MDS count. Purge the deviceid cache if zero */
 101		if (atomic_dec_and_test(&nfss->nfs_client->cl_mds_count))
 102			nfs4_deviceid_purge_client(nfss->nfs_client);
 103		module_put(nfss->pnfs_curr_ld->owner);
 104	}
 105	nfss->pnfs_curr_ld = NULL;
 106}
 107
 108/*
 109 * When the server sends a list of layout types, we choose one in the order
 110 * given in the list below.
 111 *
 112 * FIXME: should this list be configurable in some fashion? module param?
 113 * 	  mount option? something else?
 114 */
 115static const u32 ld_prefs[] = {
 116	LAYOUT_SCSI,
 117	LAYOUT_BLOCK_VOLUME,
 118	LAYOUT_OSD2_OBJECTS,
 119	LAYOUT_FLEX_FILES,
 120	LAYOUT_NFSV4_1_FILES,
 121	0
 122};
 123
 124static int
 125ld_cmp(const void *e1, const void *e2)
 126{
 127	u32 ld1 = *((u32 *)e1);
 128	u32 ld2 = *((u32 *)e2);
 129	int i;
 130
 131	for (i = 0; ld_prefs[i] != 0; i++) {
 132		if (ld1 == ld_prefs[i])
 133			return -1;
 134
 135		if (ld2 == ld_prefs[i])
 136			return 1;
 137	}
 138	return 0;
 139}
 140
 141/*
 142 * Try to set the server's pnfs module to the pnfs layout type specified by id.
 143 * Currently only one pNFS layout driver per filesystem is supported.
 144 *
 145 * @ids array of layout types supported by MDS.
 146 */
 147void
 148set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
 149		      struct nfs_fsinfo *fsinfo)
 150{
 151	struct pnfs_layoutdriver_type *ld_type = NULL;
 152	u32 id;
 153	int i;
 154
 155	if (fsinfo->nlayouttypes == 0)
 156		goto out_no_driver;
 157	if (!(server->nfs_client->cl_exchange_flags &
 158		 (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
 159		printk(KERN_ERR "NFS: %s: cl_exchange_flags 0x%x\n",
 160			__func__, server->nfs_client->cl_exchange_flags);
 161		goto out_no_driver;
 162	}
 163
 164	sort(fsinfo->layouttype, fsinfo->nlayouttypes,
 165		sizeof(*fsinfo->layouttype), ld_cmp, NULL);
 166
 167	for (i = 0; i < fsinfo->nlayouttypes; i++) {
 168		id = fsinfo->layouttype[i];
 169		ld_type = find_pnfs_driver(id);
 170		if (!ld_type) {
 171			request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX,
 172					id);
 173			ld_type = find_pnfs_driver(id);
 174		}
 175		if (ld_type)
 176			break;
 177	}
 178
 179	if (!ld_type) {
 180		dprintk("%s: No pNFS module found!\n", __func__);
 181		goto out_no_driver;
 182	}
 183
 184	server->pnfs_curr_ld = ld_type;
 185	if (ld_type->set_layoutdriver
 186	    && ld_type->set_layoutdriver(server, mntfh)) {
 187		printk(KERN_ERR "NFS: %s: Error initializing pNFS layout "
 188			"driver %u.\n", __func__, id);
 189		module_put(ld_type->owner);
 190		goto out_no_driver;
 191	}
 192	/* Bump the MDS count */
 193	atomic_inc(&server->nfs_client->cl_mds_count);
 194
 195	dprintk("%s: pNFS module for %u set\n", __func__, id);
 196	return;
 197
 198out_no_driver:
 199	dprintk("%s: Using NFSv4 I/O\n", __func__);
 200	server->pnfs_curr_ld = NULL;
 201}
 202
 203int
 204pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 205{
 206	int status = -EINVAL;
 207	struct pnfs_layoutdriver_type *tmp;
 208
 209	if (ld_type->id == 0) {
 210		printk(KERN_ERR "NFS: %s id 0 is reserved\n", __func__);
 211		return status;
 212	}
 213	if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
 214		printk(KERN_ERR "NFS: %s Layout driver must provide "
 215		       "alloc_lseg and free_lseg.\n", __func__);
 216		return status;
 217	}
 218
 219	spin_lock(&pnfs_spinlock);
 220	tmp = find_pnfs_driver_locked(ld_type->id);
 221	if (!tmp) {
 222		list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
 223		status = 0;
 224		dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
 225			ld_type->name);
 226	} else {
 227		printk(KERN_ERR "NFS: %s Module with id %d already loaded!\n",
 228			__func__, ld_type->id);
 229	}
 230	spin_unlock(&pnfs_spinlock);
 231
 232	return status;
 233}
 234EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);
 235
 236void
 237pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 238{
 239	dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
 240	spin_lock(&pnfs_spinlock);
 241	list_del(&ld_type->pnfs_tblid);
 242	spin_unlock(&pnfs_spinlock);
 243}
 244EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
 245
 246/*
 247 * pNFS client layout cache
 248 */
 249
 250/* Need to hold i_lock if caller does not already hold reference */
 251void
 252pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo)
 253{
 254	atomic_inc(&lo->plh_refcount);
 255}
 256
 257static struct pnfs_layout_hdr *
 258pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags)
 259{
 260	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
 261	return ld->alloc_layout_hdr(ino, gfp_flags);
 
 262}
 263
 264static void
 265pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
 266{
 267	struct nfs_server *server = NFS_SERVER(lo->plh_inode);
 268	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
 269
 270	if (!list_empty(&lo->plh_layouts)) {
 271		struct nfs_client *clp = server->nfs_client;
 272
 273		spin_lock(&clp->cl_lock);
 274		list_del_init(&lo->plh_layouts);
 275		spin_unlock(&clp->cl_lock);
 276	}
 277	put_rpccred(lo->plh_lc_cred);
 278	return ld->free_layout_hdr(lo);
 279}
 280
 281static void
 282pnfs_detach_layout_hdr(struct pnfs_layout_hdr *lo)
 283{
 284	struct nfs_inode *nfsi = NFS_I(lo->plh_inode);
 285	dprintk("%s: freeing layout cache %p\n", __func__, lo);
 286	nfsi->layout = NULL;
 287	/* Reset MDS Threshold I/O counters */
 288	nfsi->write_io = 0;
 289	nfsi->read_io = 0;
 290}
 291
 292void
 293pnfs_put_layout_hdr(struct pnfs_layout_hdr *lo)
 294{
 295	struct inode *inode = lo->plh_inode;
 296
 297	pnfs_layoutreturn_before_put_layout_hdr(lo);
 298
 299	if (atomic_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
 300		if (!list_empty(&lo->plh_segs))
 301			WARN_ONCE(1, "NFS: BUG unfreed layout segments.\n");
 302		pnfs_detach_layout_hdr(lo);
 303		spin_unlock(&inode->i_lock);
 304		pnfs_free_layout_hdr(lo);
 305	}
 306}
 307
 308static void
 309pnfs_set_plh_return_info(struct pnfs_layout_hdr *lo, enum pnfs_iomode iomode,
 310			 u32 seq)
 311{
 312	if (lo->plh_return_iomode != 0 && lo->plh_return_iomode != iomode)
 313		iomode = IOMODE_ANY;
 314	lo->plh_return_iomode = iomode;
 315	set_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 316	if (seq != 0) {
 317		WARN_ON_ONCE(lo->plh_return_seq != 0 && lo->plh_return_seq != seq);
 318		lo->plh_return_seq = seq;
 319	}
 320}
 321
 322static void
 323pnfs_clear_layoutreturn_info(struct pnfs_layout_hdr *lo)
 324{
 325	lo->plh_return_iomode = 0;
 326	lo->plh_return_seq = 0;
 327	clear_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags);
 328}
 329
 330static void pnfs_clear_layoutreturn_waitbit(struct pnfs_layout_hdr *lo)
 331{
 332	clear_bit_unlock(NFS_LAYOUT_RETURN, &lo->plh_flags);
 333	clear_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags);
 334	smp_mb__after_atomic();
 335	wake_up_bit(&lo->plh_flags, NFS_LAYOUT_RETURN);
 336	rpc_wake_up(&NFS_SERVER(lo->plh_inode)->roc_rpcwaitq);
 337}
 338
 339static void
 340pnfs_clear_lseg_state(struct pnfs_layout_segment *lseg,
 341		struct list_head *free_me)
 342{
 343	clear_bit(NFS_LSEG_ROC, &lseg->pls_flags);
 344	clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
 345	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags))
 346		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 347	if (test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
 348		pnfs_lseg_dec_and_remove_zero(lseg, free_me);
 349}
 350
 351/*
 352 * Mark a pnfs_layout_hdr and all associated layout segments as invalid
 353 *
 354 * In order to continue using the pnfs_layout_hdr, a full recovery
 355 * is required.
 356 * Note that caller must hold inode->i_lock.
 357 */
 358int
 359pnfs_mark_layout_stateid_invalid(struct pnfs_layout_hdr *lo,
 360		struct list_head *lseg_list)
 361{
 362	struct pnfs_layout_range range = {
 363		.iomode = IOMODE_ANY,
 364		.offset = 0,
 365		.length = NFS4_MAX_UINT64,
 366	};
 367	struct pnfs_layout_segment *lseg, *next;
 368
 369	set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 370	pnfs_clear_layoutreturn_info(lo);
 371	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 372		pnfs_clear_lseg_state(lseg, lseg_list);
 373	pnfs_free_returned_lsegs(lo, lseg_list, &range, 0);
 374	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags) &&
 375	    !test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
 376		pnfs_clear_layoutreturn_waitbit(lo);
 377	return !list_empty(&lo->plh_segs);
 378}
 379
 380static int
 381pnfs_iomode_to_fail_bit(u32 iomode)
 382{
 383	return iomode == IOMODE_RW ?
 384		NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 385}
 386
 387static void
 388pnfs_layout_set_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 389{
 390	lo->plh_retry_timestamp = jiffies;
 391	if (!test_and_set_bit(fail_bit, &lo->plh_flags))
 392		atomic_inc(&lo->plh_refcount);
 393}
 394
 395static void
 396pnfs_layout_clear_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 397{
 398	if (test_and_clear_bit(fail_bit, &lo->plh_flags))
 399		atomic_dec(&lo->plh_refcount);
 400}
 401
 402static void
 403pnfs_layout_io_set_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 404{
 405	struct inode *inode = lo->plh_inode;
 406	struct pnfs_layout_range range = {
 407		.iomode = iomode,
 408		.offset = 0,
 409		.length = NFS4_MAX_UINT64,
 410	};
 411	LIST_HEAD(head);
 412
 413	spin_lock(&inode->i_lock);
 414	pnfs_layout_set_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
 415	pnfs_mark_matching_lsegs_invalid(lo, &head, &range, 0);
 416	spin_unlock(&inode->i_lock);
 417	pnfs_free_lseg_list(&head);
 418	dprintk("%s Setting layout IOMODE_%s fail bit\n", __func__,
 419			iomode == IOMODE_RW ?  "RW" : "READ");
 420}
 421
 422static bool
 423pnfs_layout_io_test_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 424{
 425	unsigned long start, end;
 426	int fail_bit = pnfs_iomode_to_fail_bit(iomode);
 427
 428	if (test_bit(fail_bit, &lo->plh_flags) == 0)
 429		return false;
 430	end = jiffies;
 431	start = end - PNFS_LAYOUTGET_RETRY_TIMEOUT;
 432	if (!time_in_range(lo->plh_retry_timestamp, start, end)) {
 433		/* It is time to retry the failed layoutgets */
 434		pnfs_layout_clear_fail_bit(lo, fail_bit);
 435		return false;
 436	}
 437	return true;
 438}
 439
 440static void
 441pnfs_init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg,
 442		const struct pnfs_layout_range *range,
 443		const nfs4_stateid *stateid)
 444{
 445	INIT_LIST_HEAD(&lseg->pls_list);
 446	INIT_LIST_HEAD(&lseg->pls_lc_list);
 447	atomic_set(&lseg->pls_refcount, 1);
 
 448	set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
 449	lseg->pls_layout = lo;
 450	lseg->pls_range = *range;
 451	lseg->pls_seq = be32_to_cpu(stateid->seqid);
 452}
 453
 454static void pnfs_free_lseg(struct pnfs_layout_segment *lseg)
 455{
 456	if (lseg != NULL) {
 457		struct inode *inode = lseg->pls_layout->plh_inode;
 458		NFS_SERVER(inode)->pnfs_curr_ld->free_lseg(lseg);
 459	}
 
 460}
 461
 462static void
 463pnfs_layout_remove_lseg(struct pnfs_layout_hdr *lo,
 464		struct pnfs_layout_segment *lseg)
 465{
 
 
 466	WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 467	list_del_init(&lseg->pls_list);
 468	/* Matched by pnfs_get_layout_hdr in pnfs_layout_insert_lseg */
 469	atomic_dec(&lo->plh_refcount);
 470	if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
 471		return;
 472	if (list_empty(&lo->plh_segs) &&
 473	    !test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) &&
 474	    !test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
 475		if (atomic_read(&lo->plh_outstanding) == 0)
 476			set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 477		clear_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 478	}
 479}
 480
 481static bool
 482pnfs_cache_lseg_for_layoutreturn(struct pnfs_layout_hdr *lo,
 483		struct pnfs_layout_segment *lseg)
 484{
 485	if (test_and_clear_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags) &&
 486	    pnfs_layout_is_valid(lo)) {
 487		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
 488		list_move_tail(&lseg->pls_list, &lo->plh_return_segs);
 489		return true;
 490	}
 491	return false;
 492}
 493
 494void
 495pnfs_put_lseg(struct pnfs_layout_segment *lseg)
 496{
 497	struct pnfs_layout_hdr *lo;
 498	struct inode *inode;
 499
 500	if (!lseg)
 501		return;
 502
 503	dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
 504		atomic_read(&lseg->pls_refcount),
 505		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 
 
 
 506
 507	lo = lseg->pls_layout;
 508	inode = lo->plh_inode;
 509
 510	if (atomic_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
 511		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 512			spin_unlock(&inode->i_lock);
 513			return;
 514		}
 515		pnfs_get_layout_hdr(lo);
 516		pnfs_layout_remove_lseg(lo, lseg);
 517		if (pnfs_cache_lseg_for_layoutreturn(lo, lseg))
 518			lseg = NULL;
 519		spin_unlock(&inode->i_lock);
 520		pnfs_free_lseg(lseg);
 521		pnfs_put_layout_hdr(lo);
 522	}
 523}
 524EXPORT_SYMBOL_GPL(pnfs_put_lseg);
 525
 526static void pnfs_free_lseg_async_work(struct work_struct *work)
 
 527{
 528	struct pnfs_layout_segment *lseg;
 529	struct pnfs_layout_hdr *lo;
 530
 531	lseg = container_of(work, struct pnfs_layout_segment, pls_work);
 532	lo = lseg->pls_layout;
 533
 534	pnfs_free_lseg(lseg);
 535	pnfs_put_layout_hdr(lo);
 536}
 537
 538static void pnfs_free_lseg_async(struct pnfs_layout_segment *lseg)
 539{
 540	INIT_WORK(&lseg->pls_work, pnfs_free_lseg_async_work);
 541	schedule_work(&lseg->pls_work);
 542}
 543
 544void
 545pnfs_put_lseg_locked(struct pnfs_layout_segment *lseg)
 
 546{
 547	if (!lseg)
 548		return;
 549
 550	assert_spin_locked(&lseg->pls_layout->plh_inode->i_lock);
 551
 552	dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
 553		atomic_read(&lseg->pls_refcount),
 554		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 555	if (atomic_dec_and_test(&lseg->pls_refcount)) {
 556		struct pnfs_layout_hdr *lo = lseg->pls_layout;
 557		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags))
 558			return;
 559		pnfs_layout_remove_lseg(lo, lseg);
 560		if (!pnfs_cache_lseg_for_layoutreturn(lo, lseg)) {
 561			pnfs_get_layout_hdr(lo);
 562			pnfs_free_lseg_async(lseg);
 563		}
 564	}
 565}
 566EXPORT_SYMBOL_GPL(pnfs_put_lseg_locked);
 567
 568/*
 569 * is l2 fully contained in l1?
 570 *   start1                             end1
 571 *   [----------------------------------)
 572 *           start2           end2
 573 *           [----------------)
 574 */
 575static bool
 576pnfs_lseg_range_contained(const struct pnfs_layout_range *l1,
 577		 const struct pnfs_layout_range *l2)
 578{
 579	u64 start1 = l1->offset;
 580	u64 end1 = pnfs_end_offset(start1, l1->length);
 581	u64 start2 = l2->offset;
 582	u64 end2 = pnfs_end_offset(start2, l2->length);
 583
 584	return (start1 <= start2) && (end1 >= end2);
 585}
 586
 587static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
 588		struct list_head *tmp_list)
 
 
 
 
 
 
 
 
 589{
 590	if (!atomic_dec_and_test(&lseg->pls_refcount))
 591		return false;
 592	pnfs_layout_remove_lseg(lseg->pls_layout, lseg);
 593	list_add(&lseg->pls_list, tmp_list);
 594	return true;
 
 
 
 
 
 
 
 
 
 
 
 595}
 596
 597/* Returns 1 if lseg is removed from list, 0 otherwise */
 598static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
 599			     struct list_head *tmp_list)
 600{
 601	int rv = 0;
 602
 603	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 604		/* Remove the reference keeping the lseg in the
 605		 * list.  It will now be removed when all
 606		 * outstanding io is finished.
 607		 */
 608		dprintk("%s: lseg %p ref %d\n", __func__, lseg,
 609			atomic_read(&lseg->pls_refcount));
 610		if (pnfs_lseg_dec_and_remove_zero(lseg, tmp_list))
 
 
 611			rv = 1;
 
 612	}
 613	return rv;
 614}
 615
 616/*
 617 * Compare 2 layout stateid sequence ids, to see which is newer,
 618 * taking into account wraparound issues.
 619 */
 620static bool pnfs_seqid_is_newer(u32 s1, u32 s2)
 621{
 622	return (s32)(s1 - s2) > 0;
 623}
 624
 625static bool
 626pnfs_should_free_range(const struct pnfs_layout_range *lseg_range,
 627		 const struct pnfs_layout_range *recall_range)
 628{
 629	return (recall_range->iomode == IOMODE_ANY ||
 630		lseg_range->iomode == recall_range->iomode) &&
 631	       pnfs_lseg_range_intersecting(lseg_range, recall_range);
 632}
 633
 634static bool
 635pnfs_match_lseg_recall(const struct pnfs_layout_segment *lseg,
 636		const struct pnfs_layout_range *recall_range,
 637		u32 seq)
 638{
 639	if (seq != 0 && pnfs_seqid_is_newer(lseg->pls_seq, seq))
 640		return false;
 641	if (recall_range == NULL)
 642		return true;
 643	return pnfs_should_free_range(&lseg->pls_range, recall_range);
 644}
 645
 646/**
 647 * pnfs_mark_matching_lsegs_invalid - tear down lsegs or mark them for later
 648 * @lo: layout header containing the lsegs
 649 * @tmp_list: list head where doomed lsegs should go
 650 * @recall_range: optional recall range argument to match (may be NULL)
 651 * @seq: only invalidate lsegs obtained prior to this sequence (may be 0)
 652 *
 653 * Walk the list of lsegs in the layout header, and tear down any that should
 654 * be destroyed. If "recall_range" is specified then the segment must match
 655 * that range. If "seq" is non-zero, then only match segments that were handed
 656 * out at or before that sequence.
 657 *
 658 * Returns number of matching invalid lsegs remaining in list after scanning
 659 * it and purging them.
 660 */
 661int
 662pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 663			    struct list_head *tmp_list,
 664			    const struct pnfs_layout_range *recall_range,
 665			    u32 seq)
 666{
 667	struct pnfs_layout_segment *lseg, *next;
 668	int remaining = 0;
 669
 670	dprintk("%s:Begin lo %p\n", __func__, lo);
 671
 672	if (list_empty(&lo->plh_segs))
 
 
 673		return 0;
 
 674	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 675		if (pnfs_match_lseg_recall(lseg, recall_range, seq)) {
 676			dprintk("%s: freeing lseg %p iomode %d seq %u"
 
 677				"offset %llu length %llu\n", __func__,
 678				lseg, lseg->pls_range.iomode, lseg->pls_seq,
 679				lseg->pls_range.offset, lseg->pls_range.length);
 680			if (!mark_lseg_invalid(lseg, tmp_list))
 681				remaining++;
 682		}
 683	dprintk("%s:Return %i\n", __func__, remaining);
 684	return remaining;
 685}
 686
 687static void
 688pnfs_free_returned_lsegs(struct pnfs_layout_hdr *lo,
 689		struct list_head *free_me,
 690		const struct pnfs_layout_range *range,
 691		u32 seq)
 692{
 693	struct pnfs_layout_segment *lseg, *next;
 694
 695	list_for_each_entry_safe(lseg, next, &lo->plh_return_segs, pls_list) {
 696		if (pnfs_match_lseg_recall(lseg, range, seq))
 697			list_move_tail(&lseg->pls_list, free_me);
 698	}
 699}
 700
 701/* note free_me must contain lsegs from a single layout_hdr */
 702void
 703pnfs_free_lseg_list(struct list_head *free_me)
 704{
 705	struct pnfs_layout_segment *lseg, *tmp;
 
 706
 707	if (list_empty(free_me))
 708		return;
 709
 
 
 
 
 
 
 
 
 
 
 
 710	list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
 711		list_del(&lseg->pls_list);
 712		pnfs_free_lseg(lseg);
 713	}
 714}
 715
 716void
 717pnfs_destroy_layout(struct nfs_inode *nfsi)
 718{
 719	struct pnfs_layout_hdr *lo;
 720	LIST_HEAD(tmp_list);
 721
 722	spin_lock(&nfsi->vfs_inode.i_lock);
 723	lo = nfsi->layout;
 724	if (lo) {
 725		pnfs_get_layout_hdr(lo);
 726		pnfs_mark_layout_stateid_invalid(lo, &tmp_list);
 727		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RO_FAILED);
 728		pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RW_FAILED);
 729		spin_unlock(&nfsi->vfs_inode.i_lock);
 730		pnfs_free_lseg_list(&tmp_list);
 731		pnfs_put_layout_hdr(lo);
 732	} else
 733		spin_unlock(&nfsi->vfs_inode.i_lock);
 734}
 735EXPORT_SYMBOL_GPL(pnfs_destroy_layout);
 736
 737static bool
 738pnfs_layout_add_bulk_destroy_list(struct inode *inode,
 739		struct list_head *layout_list)
 740{
 741	struct pnfs_layout_hdr *lo;
 742	bool ret = false;
 743
 744	spin_lock(&inode->i_lock);
 745	lo = NFS_I(inode)->layout;
 746	if (lo != NULL && list_empty(&lo->plh_bulk_destroy)) {
 747		pnfs_get_layout_hdr(lo);
 748		list_add(&lo->plh_bulk_destroy, layout_list);
 749		ret = true;
 750	}
 751	spin_unlock(&inode->i_lock);
 752	return ret;
 753}
 754
 755/* Caller must hold rcu_read_lock and clp->cl_lock */
 756static int
 757pnfs_layout_bulk_destroy_byserver_locked(struct nfs_client *clp,
 758		struct nfs_server *server,
 759		struct list_head *layout_list)
 760{
 761	struct pnfs_layout_hdr *lo, *next;
 762	struct inode *inode;
 763
 764	list_for_each_entry_safe(lo, next, &server->layouts, plh_layouts) {
 765		if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags))
 766			continue;
 767		inode = igrab(lo->plh_inode);
 768		if (inode == NULL)
 769			continue;
 770		list_del_init(&lo->plh_layouts);
 771		if (pnfs_layout_add_bulk_destroy_list(inode, layout_list))
 772			continue;
 773		rcu_read_unlock();
 774		spin_unlock(&clp->cl_lock);
 775		iput(inode);
 776		spin_lock(&clp->cl_lock);
 777		rcu_read_lock();
 778		return -EAGAIN;
 779	}
 780	return 0;
 781}
 782
 783static int
 784pnfs_layout_free_bulk_destroy_list(struct list_head *layout_list,
 785		bool is_bulk_recall)
 786{
 
 787	struct pnfs_layout_hdr *lo;
 788	struct inode *inode;
 789	LIST_HEAD(lseg_list);
 790	int ret = 0;
 791
 792	while (!list_empty(layout_list)) {
 793		lo = list_entry(layout_list->next, struct pnfs_layout_hdr,
 794				plh_bulk_destroy);
 795		dprintk("%s freeing layout for inode %lu\n", __func__,
 796			lo->plh_inode->i_ino);
 797		inode = lo->plh_inode;
 798
 799		pnfs_layoutcommit_inode(inode, false);
 800
 801		spin_lock(&inode->i_lock);
 802		list_del_init(&lo->plh_bulk_destroy);
 803		if (pnfs_mark_layout_stateid_invalid(lo, &lseg_list)) {
 804			if (is_bulk_recall)
 805				set_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 806			ret = -EAGAIN;
 807		}
 808		spin_unlock(&inode->i_lock);
 809		pnfs_free_lseg_list(&lseg_list);
 810		/* Free all lsegs that are attached to commit buckets */
 811		nfs_commit_inode(inode, 0);
 812		pnfs_put_layout_hdr(lo);
 813		iput(inode);
 814	}
 815	return ret;
 816}
 817
 818int
 819pnfs_destroy_layouts_byfsid(struct nfs_client *clp,
 820		struct nfs_fsid *fsid,
 821		bool is_recall)
 822{
 823	struct nfs_server *server;
 824	LIST_HEAD(layout_list);
 825
 826	spin_lock(&clp->cl_lock);
 827	rcu_read_lock();
 828restart:
 829	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 830		if (memcmp(&server->fsid, fsid, sizeof(*fsid)) != 0)
 831			continue;
 832		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 833				server,
 834				&layout_list) != 0)
 835			goto restart;
 836	}
 837	rcu_read_unlock();
 838	spin_unlock(&clp->cl_lock);
 839
 840	if (list_empty(&layout_list))
 841		return 0;
 842	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 843}
 844
 845int
 846pnfs_destroy_layouts_byclid(struct nfs_client *clp,
 847		bool is_recall)
 848{
 849	struct nfs_server *server;
 850	LIST_HEAD(layout_list);
 851
 852	spin_lock(&clp->cl_lock);
 853	rcu_read_lock();
 854restart:
 855	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 856		if (pnfs_layout_bulk_destroy_byserver_locked(clp,
 857					server,
 858					&layout_list) != 0)
 859			goto restart;
 860	}
 861	rcu_read_unlock();
 862	spin_unlock(&clp->cl_lock);
 863
 864	if (list_empty(&layout_list))
 865		return 0;
 866	return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
 867}
 868
 869/*
 870 * Called by the state manger to remove all layouts established under an
 871 * expired lease.
 872 */
 873void
 874pnfs_destroy_all_layouts(struct nfs_client *clp)
 875{
 876	nfs4_deviceid_mark_client_invalid(clp);
 877	nfs4_deviceid_purge_client(clp);
 878
 879	pnfs_destroy_layouts_byclid(clp, false);
 880}
 881
 882/* update lo->plh_stateid with new if is more recent */
 883void
 884pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
 885			bool update_barrier)
 886{
 887	u32 oldseq, newseq, new_barrier = 0;
 888
 889	oldseq = be32_to_cpu(lo->plh_stateid.seqid);
 890	newseq = be32_to_cpu(new->seqid);
 891
 892	if (!pnfs_layout_is_valid(lo)) {
 893		nfs4_stateid_copy(&lo->plh_stateid, new);
 894		lo->plh_barrier = newseq;
 895		pnfs_clear_layoutreturn_info(lo);
 896		clear_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
 897		return;
 898	}
 899	if (pnfs_seqid_is_newer(newseq, oldseq)) {
 900		nfs4_stateid_copy(&lo->plh_stateid, new);
 901		/*
 902		 * Because of wraparound, we want to keep the barrier
 903		 * "close" to the current seqids.
 904		 */
 905		new_barrier = newseq - atomic_read(&lo->plh_outstanding);
 
 
 
 906	}
 907	if (update_barrier)
 908		new_barrier = be32_to_cpu(new->seqid);
 909	else if (new_barrier == 0)
 910		return;
 911	if (pnfs_seqid_is_newer(new_barrier, lo->plh_barrier))
 912		lo->plh_barrier = new_barrier;
 913}
 914
 
 915static bool
 916pnfs_layout_stateid_blocked(const struct pnfs_layout_hdr *lo,
 917		const nfs4_stateid *stateid)
 918{
 919	u32 seqid = be32_to_cpu(stateid->seqid);
 920
 921	return !pnfs_seqid_is_newer(seqid, lo->plh_barrier);
 
 
 
 
 
 922}
 923
 924/* lget is set to 1 if called from inside send_layoutget call chain */
 925static bool
 926pnfs_layoutgets_blocked(const struct pnfs_layout_hdr *lo)
 927{
 928	return lo->plh_block_lgets ||
 929		test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 930}
 931
 932/*
 933 * Get layout from server.
 934 *    for now, assume that whole file layouts are requested.
 935 *    arg->offset: 0
 936 *    arg->length: all ones
 937 */
 938static struct pnfs_layout_segment *
 939send_layoutget(struct pnfs_layout_hdr *lo,
 940	   struct nfs_open_context *ctx,
 941	   nfs4_stateid *stateid,
 942	   const struct pnfs_layout_range *range,
 943	   long *timeout, gfp_t gfp_flags)
 944{
 945	struct inode *ino = lo->plh_inode;
 946	struct nfs_server *server = NFS_SERVER(ino);
 947	struct nfs4_layoutget *lgp;
 948	loff_t i_size;
 
 
 
 949
 950	dprintk("--> %s\n", __func__);
 951
 952	/*
 953	 * Synchronously retrieve layout information from server and
 954	 * store in lseg. If we race with a concurrent seqid morphing
 955	 * op, then re-send the LAYOUTGET.
 956	 */
 957	lgp = kzalloc(sizeof(*lgp), gfp_flags);
 958	if (lgp == NULL)
 959		return ERR_PTR(-ENOMEM);
 
 
 
 
 960
 961	i_size = i_size_read(ino);
 
 
 962
 963	lgp->args.minlength = PAGE_SIZE;
 
 
 
 
 
 
 964	if (lgp->args.minlength > range->length)
 965		lgp->args.minlength = range->length;
 966	if (range->iomode == IOMODE_READ) {
 967		if (range->offset >= i_size)
 968			lgp->args.minlength = 0;
 969		else if (i_size - range->offset < lgp->args.minlength)
 970			lgp->args.minlength = i_size - range->offset;
 971	}
 972	lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
 973	pnfs_copy_range(&lgp->args.range, range);
 974	lgp->args.type = server->pnfs_curr_ld->id;
 975	lgp->args.inode = ino;
 976	lgp->args.ctx = get_nfs_open_context(ctx);
 977	nfs4_stateid_copy(&lgp->args.stateid, stateid);
 
 
 978	lgp->gfp_flags = gfp_flags;
 979	lgp->cred = lo->plh_lc_cred;
 980
 981	return nfs4_proc_layoutget(lgp, timeout, gfp_flags);
 982}
 983
 984static void pnfs_clear_layoutcommit(struct inode *inode,
 985		struct list_head *head)
 986{
 987	struct nfs_inode *nfsi = NFS_I(inode);
 988	struct pnfs_layout_segment *lseg, *tmp;
 989
 990	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
 991		return;
 992	list_for_each_entry_safe(lseg, tmp, &nfsi->layout->plh_segs, pls_list) {
 993		if (!test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
 994			continue;
 995		pnfs_lseg_dec_and_remove_zero(lseg, head);
 996	}
 997}
 998
 999void pnfs_layoutreturn_free_lsegs(struct pnfs_layout_hdr *lo,
1000		const nfs4_stateid *arg_stateid,
1001		const struct pnfs_layout_range *range,
1002		const nfs4_stateid *stateid)
1003{
1004	struct inode *inode = lo->plh_inode;
1005	LIST_HEAD(freeme);
1006
1007	spin_lock(&inode->i_lock);
1008	if (!pnfs_layout_is_valid(lo) || !arg_stateid ||
1009	    !nfs4_stateid_match_other(&lo->plh_stateid, arg_stateid))
1010		goto out_unlock;
1011	if (stateid) {
1012		u32 seq = be32_to_cpu(arg_stateid->seqid);
1013
1014		pnfs_mark_matching_lsegs_invalid(lo, &freeme, range, seq);
1015		pnfs_free_returned_lsegs(lo, &freeme, range, seq);
1016		pnfs_set_layout_stateid(lo, stateid, true);
1017	} else
1018		pnfs_mark_layout_stateid_invalid(lo, &freeme);
1019out_unlock:
1020	pnfs_clear_layoutreturn_waitbit(lo);
1021	spin_unlock(&inode->i_lock);
1022	pnfs_free_lseg_list(&freeme);
1023
1024}
1025
1026static bool
1027pnfs_prepare_layoutreturn(struct pnfs_layout_hdr *lo,
1028		nfs4_stateid *stateid,
1029		enum pnfs_iomode *iomode)
1030{
1031	/* Serialise LAYOUTGET/LAYOUTRETURN */
1032	if (atomic_read(&lo->plh_outstanding) != 0)
1033		return false;
1034	if (test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
1035		return false;
1036	set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
1037	pnfs_get_layout_hdr(lo);
1038	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags)) {
1039		if (stateid != NULL) {
1040			nfs4_stateid_copy(stateid, &lo->plh_stateid);
1041			if (lo->plh_return_seq != 0)
1042				stateid->seqid = cpu_to_be32(lo->plh_return_seq);
1043		}
1044		if (iomode != NULL)
1045			*iomode = lo->plh_return_iomode;
1046		pnfs_clear_layoutreturn_info(lo);
1047		return true;
1048	}
1049	if (stateid != NULL)
1050		nfs4_stateid_copy(stateid, &lo->plh_stateid);
1051	if (iomode != NULL)
1052		*iomode = IOMODE_ANY;
1053	return true;
1054}
1055
1056static void
1057pnfs_init_layoutreturn_args(struct nfs4_layoutreturn_args *args,
1058		struct pnfs_layout_hdr *lo,
1059		const nfs4_stateid *stateid,
1060		enum pnfs_iomode iomode)
1061{
1062	struct inode *inode = lo->plh_inode;
1063
1064	args->layout_type = NFS_SERVER(inode)->pnfs_curr_ld->id;
1065	args->inode = inode;
1066	args->range.iomode = iomode;
1067	args->range.offset = 0;
1068	args->range.length = NFS4_MAX_UINT64;
1069	args->layout = lo;
1070	nfs4_stateid_copy(&args->stateid, stateid);
1071}
1072
1073static int
1074pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo, const nfs4_stateid *stateid,
1075		       enum pnfs_iomode iomode, bool sync)
1076{
1077	struct inode *ino = lo->plh_inode;
1078	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1079	struct nfs4_layoutreturn *lrp;
1080	int status = 0;
1081
1082	lrp = kzalloc(sizeof(*lrp), GFP_NOFS);
1083	if (unlikely(lrp == NULL)) {
1084		status = -ENOMEM;
1085		spin_lock(&ino->i_lock);
1086		pnfs_clear_layoutreturn_waitbit(lo);
1087		spin_unlock(&ino->i_lock);
1088		pnfs_put_layout_hdr(lo);
1089		goto out;
1090	}
1091
1092	pnfs_init_layoutreturn_args(&lrp->args, lo, stateid, iomode);
1093	lrp->args.ld_private = &lrp->ld_private;
1094	lrp->clp = NFS_SERVER(ino)->nfs_client;
1095	lrp->cred = lo->plh_lc_cred;
1096	if (ld->prepare_layoutreturn)
1097		ld->prepare_layoutreturn(&lrp->args);
1098
1099	status = nfs4_proc_layoutreturn(lrp, sync);
1100out:
1101	dprintk("<-- %s status: %d\n", __func__, status);
1102	return status;
1103}
1104
1105/* Return true if layoutreturn is needed */
1106static bool
1107pnfs_layout_need_return(struct pnfs_layout_hdr *lo)
1108{
1109	struct pnfs_layout_segment *s;
1110
1111	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1112		return false;
1113
1114	/* Defer layoutreturn until all lsegs are done */
1115	list_for_each_entry(s, &lo->plh_segs, pls_list) {
1116		if (test_bit(NFS_LSEG_LAYOUTRETURN, &s->pls_flags))
1117			return false;
1118	}
1119
1120	return true;
1121}
1122
1123static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo)
1124{
1125	struct inode *inode= lo->plh_inode;
1126
1127	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1128		return;
1129	spin_lock(&inode->i_lock);
1130	if (pnfs_layout_need_return(lo)) {
1131		nfs4_stateid stateid;
1132		enum pnfs_iomode iomode;
1133		bool send;
1134
1135		send = pnfs_prepare_layoutreturn(lo, &stateid, &iomode);
1136		spin_unlock(&inode->i_lock);
1137		if (send) {
1138			/* Send an async layoutreturn so we dont deadlock */
1139			pnfs_send_layoutreturn(lo, &stateid, iomode, false);
1140		}
1141	} else
1142		spin_unlock(&inode->i_lock);
1143}
1144
1145/*
1146 * Initiates a LAYOUTRETURN(FILE), and removes the pnfs_layout_hdr
1147 * when the layout segment list is empty.
1148 *
1149 * Note that a pnfs_layout_hdr can exist with an empty layout segment
1150 * list when LAYOUTGET has failed, or when LAYOUTGET succeeded, but the
1151 * deviceid is marked invalid.
1152 */
1153int
1154_pnfs_return_layout(struct inode *ino)
1155{
1156	struct pnfs_layout_hdr *lo = NULL;
1157	struct nfs_inode *nfsi = NFS_I(ino);
1158	LIST_HEAD(tmp_list);
 
1159	nfs4_stateid stateid;
1160	int status = 0;
1161	bool send;
1162
1163	dprintk("NFS: %s for inode %lu\n", __func__, ino->i_ino);
1164
1165	spin_lock(&ino->i_lock);
1166	lo = nfsi->layout;
1167	if (!lo) {
1168		spin_unlock(&ino->i_lock);
1169		dprintk("NFS: %s no layout to return\n", __func__);
1170		goto out;
1171	}
 
1172	/* Reference matched in nfs4_layoutreturn_release */
1173	pnfs_get_layout_hdr(lo);
1174	/* Is there an outstanding layoutreturn ? */
1175	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1176		spin_unlock(&ino->i_lock);
1177		if (wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1178					TASK_UNINTERRUPTIBLE))
1179			goto out_put_layout_hdr;
1180		spin_lock(&ino->i_lock);
1181	}
1182	pnfs_clear_layoutcommit(ino, &tmp_list);
1183	pnfs_mark_matching_lsegs_invalid(lo, &tmp_list, NULL, 0);
1184
1185	if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) {
1186		struct pnfs_layout_range range = {
1187			.iomode		= IOMODE_ANY,
1188			.offset		= 0,
1189			.length		= NFS4_MAX_UINT64,
1190		};
1191		NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo, &range);
1192	}
1193
1194	/* Don't send a LAYOUTRETURN if list was initially empty */
1195	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags)) {
1196		spin_unlock(&ino->i_lock);
1197		dprintk("NFS: %s no layout segments to return\n", __func__);
1198		goto out_put_layout_hdr;
1199	}
1200
1201	send = pnfs_prepare_layoutreturn(lo, &stateid, NULL);
1202	spin_unlock(&ino->i_lock);
1203	if (send)
1204		status = pnfs_send_layoutreturn(lo, &stateid, IOMODE_ANY, true);
1205out_put_layout_hdr:
1206	pnfs_free_lseg_list(&tmp_list);
1207	pnfs_put_layout_hdr(lo);
1208out:
1209	dprintk("<-- %s status: %d\n", __func__, status);
1210	return status;
1211}
1212EXPORT_SYMBOL_GPL(_pnfs_return_layout);
1213
1214int
1215pnfs_commit_and_return_layout(struct inode *inode)
1216{
1217	struct pnfs_layout_hdr *lo;
1218	int ret;
 
 
1219
1220	spin_lock(&inode->i_lock);
1221	lo = NFS_I(inode)->layout;
1222	if (lo == NULL) {
1223		spin_unlock(&inode->i_lock);
1224		return 0;
1225	}
1226	pnfs_get_layout_hdr(lo);
1227	/* Block new layoutgets and read/write to ds */
 
 
 
 
1228	lo->plh_block_lgets++;
1229	spin_unlock(&inode->i_lock);
1230	filemap_fdatawait(inode->i_mapping);
1231	ret = pnfs_layoutcommit_inode(inode, true);
1232	if (ret == 0)
1233		ret = _pnfs_return_layout(inode);
1234	spin_lock(&inode->i_lock);
1235	lo->plh_block_lgets--;
1236	spin_unlock(&inode->i_lock);
1237	pnfs_put_layout_hdr(lo);
1238	return ret;
1239}
1240
1241bool pnfs_roc(struct inode *ino,
1242		struct nfs4_layoutreturn_args *args,
1243		struct nfs4_layoutreturn_res *res,
1244		const struct rpc_cred *cred)
1245{
1246	struct nfs_inode *nfsi = NFS_I(ino);
1247	struct nfs_open_context *ctx;
1248	struct nfs4_state *state;
1249	struct pnfs_layout_hdr *lo;
1250	struct pnfs_layout_segment *lseg, *next;
1251	nfs4_stateid stateid;
1252	enum pnfs_iomode iomode = 0;
1253	bool layoutreturn = false, roc = false;
1254	bool skip_read = false;
1255
1256	if (!nfs_have_layout(ino))
1257		return false;
1258retry:
1259	spin_lock(&ino->i_lock);
1260	lo = nfsi->layout;
1261	if (!lo || !pnfs_layout_is_valid(lo) ||
1262	    test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags))
1263		goto out_noroc;
1264	if (test_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags)) {
1265		pnfs_get_layout_hdr(lo);
1266		spin_unlock(&ino->i_lock);
1267		wait_on_bit(&lo->plh_flags, NFS_LAYOUT_RETURN,
1268				TASK_UNINTERRUPTIBLE);
1269		pnfs_put_layout_hdr(lo);
1270		goto retry;
1271	}
1272
1273	/* no roc if we hold a delegation */
1274	if (nfs4_check_delegation(ino, FMODE_READ)) {
1275		if (nfs4_check_delegation(ino, FMODE_WRITE))
1276			goto out_noroc;
1277		skip_read = true;
1278	}
1279
1280	list_for_each_entry(ctx, &nfsi->open_files, list) {
1281		state = ctx->state;
1282		if (state == NULL)
1283			continue;
1284		/* Don't return layout if there is open file state */
1285		if (state->state & FMODE_WRITE)
1286			goto out_noroc;
1287		if (state->state & FMODE_READ)
1288			skip_read = true;
1289	}
1290
 
 
 
1291
1292	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list) {
1293		if (skip_read && lseg->pls_range.iomode == IOMODE_READ)
1294			continue;
1295		/* If we are sending layoutreturn, invalidate all valid lsegs */
1296		if (!test_and_clear_bit(NFS_LSEG_ROC, &lseg->pls_flags))
1297			continue;
1298		/*
1299		 * Note: mark lseg for return so pnfs_layout_remove_lseg
1300		 * doesn't invalidate the layout for us.
1301		 */
1302		set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
1303		if (!mark_lseg_invalid(lseg, &lo->plh_return_segs))
1304			continue;
1305		pnfs_set_plh_return_info(lo, lseg->pls_range.iomode, 0);
1306	}
1307
1308	if (!test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
1309		goto out_noroc;
1310
1311	/* ROC in two conditions:
1312	 * 1. there are ROC lsegs
1313	 * 2. we don't send layoutreturn
1314	 */
1315	/* lo ref dropped in pnfs_roc_release() */
1316	layoutreturn = pnfs_prepare_layoutreturn(lo, &stateid, &iomode);
1317	/* If the creds don't match, we can't compound the layoutreturn */
1318	if (!layoutreturn || cred != lo->plh_lc_cred)
1319		goto out_noroc;
1320
1321	roc = layoutreturn;
1322	pnfs_init_layoutreturn_args(args, lo, &stateid, iomode);
1323	res->lrs_present = 0;
1324	layoutreturn = false;
1325
1326out_noroc:
1327	spin_unlock(&ino->i_lock);
1328	pnfs_layoutcommit_inode(ino, true);
1329	if (roc) {
1330		struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
1331		if (ld->prepare_layoutreturn)
1332			ld->prepare_layoutreturn(args);
1333		return true;
1334	}
1335	if (layoutreturn)
1336		pnfs_send_layoutreturn(lo, &stateid, iomode, true);
1337	return false;
1338}
1339
1340void pnfs_roc_release(struct nfs4_layoutreturn_args *args,
1341		struct nfs4_layoutreturn_res *res,
1342		int ret)
1343{
1344	struct pnfs_layout_hdr *lo = args->layout;
1345	const nfs4_stateid *arg_stateid = NULL;
1346	const nfs4_stateid *res_stateid = NULL;
1347	struct nfs4_xdr_opaque_data *ld_private = args->ld_private;
1348
1349	if (ret == 0) {
1350		arg_stateid = &args->stateid;
1351		if (res->lrs_present)
1352			res_stateid = &res->stateid;
1353	}
1354	pnfs_layoutreturn_free_lsegs(lo, arg_stateid, &args->range,
1355			res_stateid);
1356	if (ld_private && ld_private->ops && ld_private->ops->free)
1357		ld_private->ops->free(ld_private);
1358	pnfs_put_layout_hdr(lo);
1359	trace_nfs4_layoutreturn_on_close(args->inode, 0);
1360}
1361
1362bool pnfs_wait_on_layoutreturn(struct inode *ino, struct rpc_task *task)
1363{
1364	struct nfs_inode *nfsi = NFS_I(ino);
1365        struct pnfs_layout_hdr *lo;
1366        bool sleep = false;
1367
1368	/* we might not have grabbed lo reference. so need to check under
1369	 * i_lock */
1370        spin_lock(&ino->i_lock);
1371        lo = nfsi->layout;
1372        if (lo && test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
1373                rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
1374                sleep = true;
 
 
 
 
 
 
 
1375	}
1376        spin_unlock(&ino->i_lock);
1377        return sleep;
1378}
1379
1380/*
1381 * Compare two layout segments for sorting into layout cache.
1382 * We want to preferentially return RW over RO layouts, so ensure those
1383 * are seen first.
1384 */
1385static s64
1386pnfs_lseg_range_cmp(const struct pnfs_layout_range *l1,
1387	   const struct pnfs_layout_range *l2)
1388{
1389	s64 d;
1390
1391	/* high offset > low offset */
1392	d = l1->offset - l2->offset;
1393	if (d)
1394		return d;
1395
1396	/* short length > long length */
1397	d = l2->length - l1->length;
1398	if (d)
1399		return d;
1400
1401	/* read > read/write */
1402	return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
1403}
1404
1405static bool
1406pnfs_lseg_range_is_after(const struct pnfs_layout_range *l1,
1407		const struct pnfs_layout_range *l2)
1408{
1409	return pnfs_lseg_range_cmp(l1, l2) > 0;
1410}
1411
1412static bool
1413pnfs_lseg_no_merge(struct pnfs_layout_segment *lseg,
1414		struct pnfs_layout_segment *old)
1415{
1416	return false;
1417}
1418
1419void
1420pnfs_generic_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1421		   struct pnfs_layout_segment *lseg,
1422		   bool (*is_after)(const struct pnfs_layout_range *,
1423			   const struct pnfs_layout_range *),
1424		   bool (*do_merge)(struct pnfs_layout_segment *,
1425			   struct pnfs_layout_segment *),
1426		   struct list_head *free_me)
1427{
1428	struct pnfs_layout_segment *lp, *tmp;
1429
1430	dprintk("%s:Begin\n", __func__);
1431
1432	list_for_each_entry_safe(lp, tmp, &lo->plh_segs, pls_list) {
1433		if (test_bit(NFS_LSEG_VALID, &lp->pls_flags) == 0)
1434			continue;
1435		if (do_merge(lseg, lp)) {
1436			mark_lseg_invalid(lp, free_me);
1437			continue;
1438		}
1439		if (is_after(&lseg->pls_range, &lp->pls_range))
1440			continue;
1441		list_add_tail(&lseg->pls_list, &lp->pls_list);
1442		dprintk("%s: inserted lseg %p "
1443			"iomode %d offset %llu length %llu before "
1444			"lp %p iomode %d offset %llu length %llu\n",
1445			__func__, lseg, lseg->pls_range.iomode,
1446			lseg->pls_range.offset, lseg->pls_range.length,
1447			lp, lp->pls_range.iomode, lp->pls_range.offset,
1448			lp->pls_range.length);
1449		goto out;
1450	}
1451	list_add_tail(&lseg->pls_list, &lo->plh_segs);
1452	dprintk("%s: inserted lseg %p "
1453		"iomode %d offset %llu length %llu at tail\n",
1454		__func__, lseg, lseg->pls_range.iomode,
1455		lseg->pls_range.offset, lseg->pls_range.length);
1456out:
1457	pnfs_get_layout_hdr(lo);
1458
1459	dprintk("%s:Return\n", __func__);
1460}
1461EXPORT_SYMBOL_GPL(pnfs_generic_layout_insert_lseg);
1462
1463static void
1464pnfs_layout_insert_lseg(struct pnfs_layout_hdr *lo,
1465		   struct pnfs_layout_segment *lseg,
1466		   struct list_head *free_me)
1467{
1468	struct inode *inode = lo->plh_inode;
1469	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
1470
1471	if (ld->add_lseg != NULL)
1472		ld->add_lseg(lo, lseg, free_me);
1473	else
1474		pnfs_generic_layout_insert_lseg(lo, lseg,
1475				pnfs_lseg_range_is_after,
1476				pnfs_lseg_no_merge,
1477				free_me);
1478}
1479
1480static struct pnfs_layout_hdr *
1481alloc_init_layout_hdr(struct inode *ino,
1482		      struct nfs_open_context *ctx,
1483		      gfp_t gfp_flags)
1484{
1485	struct pnfs_layout_hdr *lo;
1486
1487	lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
1488	if (!lo)
1489		return NULL;
1490	atomic_set(&lo->plh_refcount, 1);
1491	INIT_LIST_HEAD(&lo->plh_layouts);
1492	INIT_LIST_HEAD(&lo->plh_segs);
1493	INIT_LIST_HEAD(&lo->plh_return_segs);
1494	INIT_LIST_HEAD(&lo->plh_bulk_destroy);
1495	lo->plh_inode = ino;
1496	lo->plh_lc_cred = get_rpccred(ctx->cred);
1497	lo->plh_flags |= 1 << NFS_LAYOUT_INVALID_STID;
1498	return lo;
1499}
1500
1501static struct pnfs_layout_hdr *
1502pnfs_find_alloc_layout(struct inode *ino,
1503		       struct nfs_open_context *ctx,
1504		       gfp_t gfp_flags)
1505	__releases(&ino->i_lock)
1506	__acquires(&ino->i_lock)
1507{
1508	struct nfs_inode *nfsi = NFS_I(ino);
1509	struct pnfs_layout_hdr *new = NULL;
1510
1511	dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
1512
1513	if (nfsi->layout != NULL)
1514		goto out_existing;
 
 
 
 
 
1515	spin_unlock(&ino->i_lock);
1516	new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
1517	spin_lock(&ino->i_lock);
1518
1519	if (likely(nfsi->layout == NULL)) {	/* Won the race? */
1520		nfsi->layout = new;
1521		return new;
1522	} else if (new != NULL)
1523		pnfs_free_layout_hdr(new);
1524out_existing:
1525	pnfs_get_layout_hdr(nfsi->layout);
1526	return nfsi->layout;
1527}
1528
1529/*
1530 * iomode matching rules:
1531 * iomode	lseg	strict match
1532 *                      iomode
1533 * -----	-----	------ -----
1534 * ANY		READ	N/A    true
1535 * ANY		RW	N/A    true
1536 * RW		READ	N/A    false
1537 * RW		RW	N/A    true
1538 * READ		READ	N/A    true
1539 * READ		RW	true   false
1540 * READ		RW	false  true
1541 */
1542static bool
1543pnfs_lseg_range_match(const struct pnfs_layout_range *ls_range,
1544		 const struct pnfs_layout_range *range,
1545		 bool strict_iomode)
1546{
1547	struct pnfs_layout_range range1;
1548
1549	if ((range->iomode == IOMODE_RW &&
1550	     ls_range->iomode != IOMODE_RW) ||
1551	    (range->iomode != ls_range->iomode &&
1552	     strict_iomode == true) ||
1553	    !pnfs_lseg_range_intersecting(ls_range, range))
1554		return 0;
1555
1556	/* range1 covers only the first byte in the range */
1557	range1 = *range;
1558	range1.length = 1;
1559	return pnfs_lseg_range_contained(ls_range, &range1);
1560}
1561
1562/*
1563 * lookup range in layout
1564 */
1565static struct pnfs_layout_segment *
1566pnfs_find_lseg(struct pnfs_layout_hdr *lo,
1567		struct pnfs_layout_range *range,
1568		bool strict_iomode)
1569{
1570	struct pnfs_layout_segment *lseg, *ret = NULL;
1571
1572	dprintk("%s:Begin\n", __func__);
1573
 
1574	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
1575		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
1576		    !test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags) &&
1577		    pnfs_lseg_range_match(&lseg->pls_range, range,
1578					  strict_iomode)) {
1579			ret = pnfs_get_lseg(lseg);
1580			break;
1581		}
 
 
1582	}
1583
1584	dprintk("%s:Return lseg %p ref %d\n",
1585		__func__, ret, ret ? atomic_read(&ret->pls_refcount) : 0);
1586	return ret;
1587}
1588
1589/*
1590 * Use mdsthreshold hints set at each OPEN to determine if I/O should go
1591 * to the MDS or over pNFS
1592 *
1593 * The nfs_inode read_io and write_io fields are cumulative counters reset
1594 * when there are no layout segments. Note that in pnfs_update_layout iomode
1595 * is set to IOMODE_READ for a READ request, and set to IOMODE_RW for a
1596 * WRITE request.
1597 *
1598 * A return of true means use MDS I/O.
1599 *
1600 * From rfc 5661:
1601 * If a file's size is smaller than the file size threshold, data accesses
1602 * SHOULD be sent to the metadata server.  If an I/O request has a length that
1603 * is below the I/O size threshold, the I/O SHOULD be sent to the metadata
1604 * server.  If both file size and I/O size are provided, the client SHOULD
1605 * reach or exceed  both thresholds before sending its read or write
1606 * requests to the data server.
1607 */
1608static bool pnfs_within_mdsthreshold(struct nfs_open_context *ctx,
1609				     struct inode *ino, int iomode)
1610{
1611	struct nfs4_threshold *t = ctx->mdsthreshold;
1612	struct nfs_inode *nfsi = NFS_I(ino);
1613	loff_t fsize = i_size_read(ino);
1614	bool size = false, size_set = false, io = false, io_set = false, ret = false;
1615
1616	if (t == NULL)
1617		return ret;
1618
1619	dprintk("%s bm=0x%x rd_sz=%llu wr_sz=%llu rd_io=%llu wr_io=%llu\n",
1620		__func__, t->bm, t->rd_sz, t->wr_sz, t->rd_io_sz, t->wr_io_sz);
1621
1622	switch (iomode) {
1623	case IOMODE_READ:
1624		if (t->bm & THRESHOLD_RD) {
1625			dprintk("%s fsize %llu\n", __func__, fsize);
1626			size_set = true;
1627			if (fsize < t->rd_sz)
1628				size = true;
1629		}
1630		if (t->bm & THRESHOLD_RD_IO) {
1631			dprintk("%s nfsi->read_io %llu\n", __func__,
1632				nfsi->read_io);
1633			io_set = true;
1634			if (nfsi->read_io < t->rd_io_sz)
1635				io = true;
1636		}
1637		break;
1638	case IOMODE_RW:
1639		if (t->bm & THRESHOLD_WR) {
1640			dprintk("%s fsize %llu\n", __func__, fsize);
1641			size_set = true;
1642			if (fsize < t->wr_sz)
1643				size = true;
1644		}
1645		if (t->bm & THRESHOLD_WR_IO) {
1646			dprintk("%s nfsi->write_io %llu\n", __func__,
1647				nfsi->write_io);
1648			io_set = true;
1649			if (nfsi->write_io < t->wr_io_sz)
1650				io = true;
1651		}
1652		break;
1653	}
1654	if (size_set && io_set) {
1655		if (size && io)
1656			ret = true;
1657	} else if (size || io)
1658		ret = true;
1659
1660	dprintk("<-- %s size %d io %d ret %d\n", __func__, size, io, ret);
1661	return ret;
1662}
1663
1664static bool pnfs_prepare_to_retry_layoutget(struct pnfs_layout_hdr *lo)
1665{
1666	/*
1667	 * send layoutcommit as it can hold up layoutreturn due to lseg
1668	 * reference
1669	 */
1670	pnfs_layoutcommit_inode(lo->plh_inode, false);
1671	return !wait_on_bit_action(&lo->plh_flags, NFS_LAYOUT_RETURN,
1672				   nfs_wait_bit_killable,
1673				   TASK_UNINTERRUPTIBLE);
1674}
1675
1676static void pnfs_clear_first_layoutget(struct pnfs_layout_hdr *lo)
1677{
1678	unsigned long *bitlock = &lo->plh_flags;
1679
1680	clear_bit_unlock(NFS_LAYOUT_FIRST_LAYOUTGET, bitlock);
1681	smp_mb__after_atomic();
1682	wake_up_bit(bitlock, NFS_LAYOUT_FIRST_LAYOUTGET);
1683}
1684
1685/*
1686 * Layout segment is retreived from the server if not cached.
1687 * The appropriate layout segment is referenced and returned to the caller.
1688 */
1689struct pnfs_layout_segment *
1690pnfs_update_layout(struct inode *ino,
1691		   struct nfs_open_context *ctx,
1692		   loff_t pos,
1693		   u64 count,
1694		   enum pnfs_iomode iomode,
1695		   bool strict_iomode,
1696		   gfp_t gfp_flags)
1697{
1698	struct pnfs_layout_range arg = {
1699		.iomode = iomode,
1700		.offset = pos,
1701		.length = count,
1702	};
1703	unsigned pg_offset, seq;
 
1704	struct nfs_server *server = NFS_SERVER(ino);
1705	struct nfs_client *clp = server->nfs_client;
1706	struct pnfs_layout_hdr *lo = NULL;
1707	struct pnfs_layout_segment *lseg = NULL;
1708	nfs4_stateid stateid;
1709	long timeout = 0;
1710	unsigned long giveup = jiffies + (clp->cl_lease_time << 1);
1711	bool first;
1712
1713	if (!pnfs_enabled_sb(NFS_SERVER(ino))) {
1714		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1715				 PNFS_UPDATE_LAYOUT_NO_PNFS);
1716		goto out;
1717	}
1718
1719	if (iomode == IOMODE_READ && i_size_read(ino) == 0) {
1720		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1721				 PNFS_UPDATE_LAYOUT_RD_ZEROLEN);
1722		goto out;
1723	}
1724
1725	if (pnfs_within_mdsthreshold(ctx, ino, iomode)) {
1726		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1727				 PNFS_UPDATE_LAYOUT_MDSTHRESH);
1728		goto out;
1729	}
1730
1731lookup_again:
1732	nfs4_client_recover_expired_lease(clp);
1733	first = false;
1734	spin_lock(&ino->i_lock);
1735	lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
1736	if (lo == NULL) {
1737		spin_unlock(&ino->i_lock);
1738		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1739				 PNFS_UPDATE_LAYOUT_NOMEM);
1740		goto out;
1741	}
1742
1743	/* Do we even need to bother with this? */
1744	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1745		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1746				 PNFS_UPDATE_LAYOUT_BULK_RECALL);
1747		dprintk("%s matches recall, use MDS\n", __func__);
1748		goto out_unlock;
1749	}
1750
1751	/* if LAYOUTGET already failed once we don't try again */
1752	if (pnfs_layout_io_test_failed(lo, iomode)) {
1753		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1754				 PNFS_UPDATE_LAYOUT_IO_TEST_FAIL);
1755		goto out_unlock;
1756	}
1757
1758	lseg = pnfs_find_lseg(lo, &arg, strict_iomode);
1759	if (lseg) {
1760		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1761				PNFS_UPDATE_LAYOUT_FOUND_CACHED);
1762		goto out_unlock;
1763	}
1764
1765	if (!nfs4_valid_open_stateid(ctx->state)) {
1766		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1767				PNFS_UPDATE_LAYOUT_INVALID_OPEN);
1768		goto out_unlock;
1769	}
1770
1771	/*
1772	 * Choose a stateid for the LAYOUTGET. If we don't have a layout
1773	 * stateid, or it has been invalidated, then we must use the open
1774	 * stateid.
1775	 */
1776	if (test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags)) {
1777
1778		/*
1779		 * The first layoutget for the file. Need to serialize per
1780		 * RFC 5661 Errata 3208.
1781		 */
1782		if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET,
1783				     &lo->plh_flags)) {
1784			spin_unlock(&ino->i_lock);
1785			wait_on_bit(&lo->plh_flags, NFS_LAYOUT_FIRST_LAYOUTGET,
1786				    TASK_UNINTERRUPTIBLE);
1787			pnfs_put_layout_hdr(lo);
1788			dprintk("%s retrying\n", __func__);
1789			goto lookup_again;
1790		}
1791
 
 
1792		first = true;
1793		do {
1794			seq = read_seqbegin(&ctx->state->seqlock);
1795			nfs4_stateid_copy(&stateid, &ctx->state->stateid);
1796		} while (read_seqretry(&ctx->state->seqlock, seq));
1797	} else {
1798		nfs4_stateid_copy(&stateid, &lo->plh_stateid);
1799	}
1800
1801	/*
1802	 * Because we free lsegs before sending LAYOUTRETURN, we need to wait
1803	 * for LAYOUTRETURN even if first is true.
1804	 */
1805	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
1806		spin_unlock(&ino->i_lock);
1807		dprintk("%s wait for layoutreturn\n", __func__);
1808		if (pnfs_prepare_to_retry_layoutget(lo)) {
1809			if (first)
1810				pnfs_clear_first_layoutget(lo);
1811			pnfs_put_layout_hdr(lo);
1812			dprintk("%s retrying\n", __func__);
1813			trace_pnfs_update_layout(ino, pos, count, iomode, lo,
1814					lseg, PNFS_UPDATE_LAYOUT_RETRY);
1815			goto lookup_again;
1816		}
1817		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1818				PNFS_UPDATE_LAYOUT_RETURN);
1819		goto out_put_layout_hdr;
1820	}
1821
1822	if (pnfs_layoutgets_blocked(lo)) {
1823		trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1824				PNFS_UPDATE_LAYOUT_BLOCKED);
1825		goto out_unlock;
1826	}
1827	atomic_inc(&lo->plh_outstanding);
1828	spin_unlock(&ino->i_lock);
1829
1830	if (list_empty(&lo->plh_layouts)) {
1831		/* The lo must be on the clp list if there is any
1832		 * chance of a CB_LAYOUTRECALL(FILE) coming in.
1833		 */
1834		spin_lock(&clp->cl_lock);
1835		if (list_empty(&lo->plh_layouts))
1836			list_add_tail(&lo->plh_layouts, &server->layouts);
1837		spin_unlock(&clp->cl_lock);
1838	}
1839
1840	pg_offset = arg.offset & ~PAGE_MASK;
1841	if (pg_offset) {
1842		arg.offset -= pg_offset;
1843		arg.length += pg_offset;
1844	}
1845	if (arg.length != NFS4_MAX_UINT64)
1846		arg.length = PAGE_ALIGN(arg.length);
1847
1848	lseg = send_layoutget(lo, ctx, &stateid, &arg, &timeout, gfp_flags);
1849	trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
1850				 PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET);
 
 
 
1851	atomic_dec(&lo->plh_outstanding);
1852	if (IS_ERR(lseg)) {
1853		switch(PTR_ERR(lseg)) {
1854		case -EBUSY:
1855			if (time_after(jiffies, giveup))
1856				lseg = NULL;
1857			break;
1858		case -ERECALLCONFLICT:
1859			/* Huh? We hold no layouts, how is there a recall? */
1860			if (first) {
1861				lseg = NULL;
1862				break;
1863			}
1864			/* Destroy the existing layout and start over */
1865			if (time_after(jiffies, giveup))
1866				pnfs_destroy_layout(NFS_I(ino));
1867			/* Fallthrough */
1868		case -EAGAIN:
1869			break;
1870		default:
1871			if (!nfs_error_is_fatal(PTR_ERR(lseg))) {
1872				pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
1873				lseg = NULL;
1874			}
1875			goto out_put_layout_hdr;
1876		}
1877		if (lseg) {
1878			if (first)
1879				pnfs_clear_first_layoutget(lo);
1880			trace_pnfs_update_layout(ino, pos, count,
1881				iomode, lo, lseg, PNFS_UPDATE_LAYOUT_RETRY);
1882			pnfs_put_layout_hdr(lo);
1883			goto lookup_again;
1884		}
1885	} else {
1886		pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
1887	}
1888
1889out_put_layout_hdr:
1890	if (first)
1891		pnfs_clear_first_layoutget(lo);
1892	pnfs_put_layout_hdr(lo);
1893out:
1894	dprintk("%s: inode %s/%llu pNFS layout segment %s for "
1895			"(%s, offset: %llu, length: %llu)\n",
1896			__func__, ino->i_sb->s_id,
1897			(unsigned long long)NFS_FILEID(ino),
1898			IS_ERR_OR_NULL(lseg) ? "not found" : "found",
1899			iomode==IOMODE_RW ?  "read/write" : "read-only",
1900			(unsigned long long)pos,
1901			(unsigned long long)count);
1902	return lseg;
1903out_unlock:
1904	spin_unlock(&ino->i_lock);
1905	goto out_put_layout_hdr;
1906}
1907EXPORT_SYMBOL_GPL(pnfs_update_layout);
1908
1909static bool
1910pnfs_sanity_check_layout_range(struct pnfs_layout_range *range)
1911{
1912	switch (range->iomode) {
1913	case IOMODE_READ:
1914	case IOMODE_RW:
1915		break;
1916	default:
1917		return false;
1918	}
1919	if (range->offset == NFS4_MAX_UINT64)
1920		return false;
1921	if (range->length == 0)
1922		return false;
1923	if (range->length != NFS4_MAX_UINT64 &&
1924	    range->length > NFS4_MAX_UINT64 - range->offset)
1925		return false;
1926	return true;
1927}
1928
1929struct pnfs_layout_segment *
1930pnfs_layout_process(struct nfs4_layoutget *lgp)
1931{
1932	struct pnfs_layout_hdr *lo = NFS_I(lgp->args.inode)->layout;
1933	struct nfs4_layoutget_res *res = &lgp->res;
1934	struct pnfs_layout_segment *lseg;
1935	struct inode *ino = lo->plh_inode;
1936	LIST_HEAD(free_me);
1937
1938	if (!pnfs_sanity_check_layout_range(&res->range))
1939		return ERR_PTR(-EINVAL);
1940
1941	/* Inject layout blob into I/O device driver */
1942	lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
1943	if (IS_ERR_OR_NULL(lseg)) {
1944		if (!lseg)
1945			lseg = ERR_PTR(-ENOMEM);
1946
1947		dprintk("%s: Could not allocate layout: error %ld\n",
1948		       __func__, PTR_ERR(lseg));
1949		return lseg;
 
1950	}
1951
1952	pnfs_init_lseg(lo, lseg, &res->range, &res->stateid);
1953
1954	spin_lock(&ino->i_lock);
1955	if (pnfs_layoutgets_blocked(lo)) {
1956		dprintk("%s forget reply due to state\n", __func__);
1957		goto out_forget;
 
1958	}
1959
1960	if (!pnfs_layout_is_valid(lo)) {
1961		/* We have a completely new layout */
1962		pnfs_set_layout_stateid(lo, &res->stateid, true);
1963	} else if (nfs4_stateid_match_other(&lo->plh_stateid, &res->stateid)) {
1964		/* existing state ID, make sure the sequence number matches. */
1965		if (pnfs_layout_stateid_blocked(lo, &res->stateid)) {
1966			dprintk("%s forget reply due to sequence\n", __func__);
1967			goto out_forget;
1968		}
1969		pnfs_set_layout_stateid(lo, &res->stateid, false);
1970	} else {
1971		/*
1972		 * We got an entirely new state ID.  Mark all segments for the
1973		 * inode invalid, and retry the layoutget
1974		 */
1975		pnfs_mark_layout_stateid_invalid(lo, &free_me);
1976		goto out_forget;
1977	}
 
 
 
 
1978
1979	pnfs_get_lseg(lseg);
1980	pnfs_layout_insert_lseg(lo, lseg, &free_me);
1981
1982
1983	if (res->return_on_close)
1984		set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
 
 
1985
 
 
1986	spin_unlock(&ino->i_lock);
1987	pnfs_free_lseg_list(&free_me);
1988	return lseg;
1989
1990out_forget:
1991	spin_unlock(&ino->i_lock);
1992	lseg->pls_layout = lo;
1993	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
1994	return ERR_PTR(-EAGAIN);
1995}
1996
1997/**
1998 * pnfs_mark_matching_lsegs_return - Free or return matching layout segments
1999 * @lo: pointer to layout header
2000 * @tmp_list: list header to be used with pnfs_free_lseg_list()
2001 * @return_range: describe layout segment ranges to be returned
2002 *
2003 * This function is mainly intended for use by layoutrecall. It attempts
2004 * to free the layout segment immediately, or else to mark it for return
2005 * as soon as its reference count drops to zero.
2006 */
2007int
2008pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
2009				struct list_head *tmp_list,
2010				const struct pnfs_layout_range *return_range,
2011				u32 seq)
2012{
2013	struct pnfs_layout_segment *lseg, *next;
2014	int remaining = 0;
2015
2016	dprintk("%s:Begin lo %p\n", __func__, lo);
2017
2018	if (list_empty(&lo->plh_segs))
2019		return 0;
2020
2021	assert_spin_locked(&lo->plh_inode->i_lock);
2022
2023	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
2024		if (pnfs_match_lseg_recall(lseg, return_range, seq)) {
2025			dprintk("%s: marking lseg %p iomode %d "
2026				"offset %llu length %llu\n", __func__,
2027				lseg, lseg->pls_range.iomode,
2028				lseg->pls_range.offset,
2029				lseg->pls_range.length);
2030			if (mark_lseg_invalid(lseg, tmp_list))
2031				continue;
2032			remaining++;
2033			set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
2034		}
2035
2036	if (remaining)
2037		pnfs_set_plh_return_info(lo, return_range->iomode, seq);
2038
2039	return remaining;
2040}
2041
2042void pnfs_error_mark_layout_for_return(struct inode *inode,
2043				       struct pnfs_layout_segment *lseg)
2044{
2045	struct pnfs_layout_hdr *lo = NFS_I(inode)->layout;
2046	struct pnfs_layout_range range = {
2047		.iomode = lseg->pls_range.iomode,
2048		.offset = 0,
2049		.length = NFS4_MAX_UINT64,
2050	};
2051	bool return_now = false;
2052
2053	spin_lock(&inode->i_lock);
2054	pnfs_set_plh_return_info(lo, range.iomode, 0);
2055	/* Block LAYOUTGET */
2056	set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
2057	/*
2058	 * mark all matching lsegs so that we are sure to have no live
2059	 * segments at hand when sending layoutreturn. See pnfs_put_lseg()
2060	 * for how it works.
2061	 */
2062	if (!pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs, &range, 0)) {
2063		nfs4_stateid stateid;
2064		enum pnfs_iomode iomode;
2065
2066		return_now = pnfs_prepare_layoutreturn(lo, &stateid, &iomode);
2067		spin_unlock(&inode->i_lock);
2068		if (return_now)
2069			pnfs_send_layoutreturn(lo, &stateid, iomode, false);
2070	} else {
2071		spin_unlock(&inode->i_lock);
2072		nfs_commit_inode(inode, 0);
2073	}
2074}
2075EXPORT_SYMBOL_GPL(pnfs_error_mark_layout_for_return);
2076
2077void
2078pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
2079{
2080	u64 rd_size = req->wb_bytes;
2081
2082	if (pgio->pg_lseg == NULL) {
2083		if (pgio->pg_dreq == NULL)
2084			rd_size = i_size_read(pgio->pg_inode) - req_offset(req);
2085		else
2086			rd_size = nfs_dreq_bytes_left(pgio->pg_dreq);
2087
2088		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
2089						   req->wb_context,
2090						   req_offset(req),
2091						   rd_size,
2092						   IOMODE_READ,
2093						   false,
2094						   GFP_KERNEL);
2095		if (IS_ERR(pgio->pg_lseg)) {
2096			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2097			pgio->pg_lseg = NULL;
2098			return;
2099		}
2100	}
2101	/* If no lseg, fall back to read through mds */
2102	if (pgio->pg_lseg == NULL)
2103		nfs_pageio_reset_read_mds(pgio);
2104
2105}
2106EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);
2107
2108void
2109pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
2110			   struct nfs_page *req, u64 wb_size)
2111{
2112	if (pgio->pg_lseg == NULL) {
2113		pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
2114						   req->wb_context,
2115						   req_offset(req),
2116						   wb_size,
2117						   IOMODE_RW,
2118						   false,
2119						   GFP_NOFS);
2120		if (IS_ERR(pgio->pg_lseg)) {
2121			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
2122			pgio->pg_lseg = NULL;
2123			return;
2124		}
2125	}
2126	/* If no lseg, fall back to write through mds */
2127	if (pgio->pg_lseg == NULL)
2128		nfs_pageio_reset_write_mds(pgio);
2129}
2130EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
2131
2132void
2133pnfs_generic_pg_cleanup(struct nfs_pageio_descriptor *desc)
2134{
2135	if (desc->pg_lseg) {
2136		pnfs_put_lseg(desc->pg_lseg);
2137		desc->pg_lseg = NULL;
2138	}
 
 
 
2139}
2140EXPORT_SYMBOL_GPL(pnfs_generic_pg_cleanup);
2141
2142/*
2143 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
2144 * of bytes (maximum @req->wb_bytes) that can be coalesced.
2145 */
2146size_t
2147pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio,
2148		     struct nfs_page *prev, struct nfs_page *req)
2149{
2150	unsigned int size;
2151	u64 seg_end, req_start, seg_left;
2152
2153	size = nfs_generic_pg_test(pgio, prev, req);
2154	if (!size)
2155		return 0;
 
 
 
 
 
 
 
 
 
2156
2157	/*
2158	 * 'size' contains the number of bytes left in the current page (up
2159	 * to the original size asked for in @req->wb_bytes).
2160	 *
2161	 * Calculate how many bytes are left in the layout segment
2162	 * and if there are less bytes than 'size', return that instead.
 
 
 
2163	 *
2164	 * Please also note that 'end_offset' is actually the offset of the
2165	 * first byte that lies outside the pnfs_layout_range. FIXME?
2166	 *
2167	 */
2168	if (pgio->pg_lseg) {
2169		seg_end = pnfs_end_offset(pgio->pg_lseg->pls_range.offset,
2170				     pgio->pg_lseg->pls_range.length);
2171		req_start = req_offset(req);
2172		WARN_ON_ONCE(req_start >= seg_end);
2173		/* start of request is past the last byte of this segment */
2174		if (req_start >= seg_end) {
2175			/* reference the new lseg */
2176			if (pgio->pg_ops->pg_cleanup)
2177				pgio->pg_ops->pg_cleanup(pgio);
2178			if (pgio->pg_ops->pg_init)
2179				pgio->pg_ops->pg_init(pgio, req);
2180			return 0;
2181		}
2182
2183		/* adjust 'size' iff there are fewer bytes left in the
2184		 * segment than what nfs_generic_pg_test returned */
2185		seg_left = seg_end - req_start;
2186		if (seg_left < size)
2187			size = (unsigned int)seg_left;
2188	}
2189
2190	return size;
2191}
2192EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
2193
2194int pnfs_write_done_resend_to_mds(struct nfs_pgio_header *hdr)
 
 
 
 
2195{
2196	struct nfs_pageio_descriptor pgio;
2197
2198	/* Resend all requests through the MDS */
2199	nfs_pageio_init_write(&pgio, hdr->inode, FLUSH_STABLE, true,
2200			      hdr->completion_ops);
2201	set_bit(NFS_CONTEXT_RESEND_WRITES, &hdr->args.context->flags);
2202	return nfs_pageio_resend(&pgio, hdr);
2203}
2204EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
2205
2206static void pnfs_ld_handle_write_error(struct nfs_pgio_header *hdr)
2207{
2208
2209	dprintk("pnfs write error = %d\n", hdr->pnfs_error);
2210	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2211	    PNFS_LAYOUTRET_ON_ERROR) {
2212		pnfs_return_layout(hdr->inode);
2213	}
2214	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2215		hdr->task.tk_status = pnfs_write_done_resend_to_mds(hdr);
2216}
2217
2218/*
2219 * Called by non rpc-based layout drivers
2220 */
2221void pnfs_ld_write_done(struct nfs_pgio_header *hdr)
2222{
2223	if (likely(!hdr->pnfs_error)) {
2224		pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
2225				hdr->mds_offset + hdr->res.count);
2226		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
2227	}
2228	trace_nfs4_pnfs_write(hdr, hdr->pnfs_error);
2229	if (unlikely(hdr->pnfs_error))
2230		pnfs_ld_handle_write_error(hdr);
2231	hdr->mds_ops->rpc_release(hdr);
2232}
2233EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
2234
2235static void
2236pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
2237		struct nfs_pgio_header *hdr)
2238{
2239	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2240
2241	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2242		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
2243		nfs_pageio_reset_write_mds(desc);
2244		mirror->pg_recoalesce = 1;
2245	}
2246	nfs_pgio_data_destroy(hdr);
2247	hdr->release(hdr);
2248}
2249
2250static enum pnfs_try_status
2251pnfs_try_to_write_data(struct nfs_pgio_header *hdr,
2252			const struct rpc_call_ops *call_ops,
2253			struct pnfs_layout_segment *lseg,
2254			int how)
2255{
2256	struct inode *inode = hdr->inode;
2257	enum pnfs_try_status trypnfs;
2258	struct nfs_server *nfss = NFS_SERVER(inode);
2259
2260	hdr->mds_ops = call_ops;
 
2261
2262	dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
2263		inode->i_ino, hdr->args.count, hdr->args.offset, how);
2264	trypnfs = nfss->pnfs_curr_ld->write_pagelist(hdr, how);
2265	if (trypnfs != PNFS_NOT_ATTEMPTED)
 
 
 
 
2266		nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
 
2267	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
2268	return trypnfs;
2269}
2270
2271static void
2272pnfs_do_write(struct nfs_pageio_descriptor *desc,
2273	      struct nfs_pgio_header *hdr, int how)
2274{
 
2275	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
2276	struct pnfs_layout_segment *lseg = desc->pg_lseg;
2277	enum pnfs_try_status trypnfs;
2278
2279	trypnfs = pnfs_try_to_write_data(hdr, call_ops, lseg, how);
2280	if (trypnfs == PNFS_NOT_ATTEMPTED)
2281		pnfs_write_through_mds(desc, hdr);
2282}
2283
2284static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
2285{
2286	pnfs_put_lseg(hdr->lseg);
2287	nfs_pgio_header_free(hdr);
 
 
 
2288}
2289
2290int
2291pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
2292{
2293	struct nfs_pgio_header *hdr;
2294	int ret;
2295
2296	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
2297	if (!hdr) {
2298		desc->pg_error = -ENOMEM;
2299		return desc->pg_error;
2300	}
2301	nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
2302
2303	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
2304	ret = nfs_generic_pgio(desc, hdr);
2305	if (!ret)
2306		pnfs_do_write(desc, hdr, desc->pg_ioflags);
2307
2308	return ret;
2309}
2310EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
2311
2312int pnfs_read_done_resend_to_mds(struct nfs_pgio_header *hdr)
 
 
 
 
2313{
2314	struct nfs_pageio_descriptor pgio;
2315
2316	/* Resend all requests through the MDS */
2317	nfs_pageio_init_read(&pgio, hdr->inode, true, hdr->completion_ops);
2318	return nfs_pageio_resend(&pgio, hdr);
2319}
2320EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
2321
2322static void pnfs_ld_handle_read_error(struct nfs_pgio_header *hdr)
2323{
2324	dprintk("pnfs read error = %d\n", hdr->pnfs_error);
2325	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
2326	    PNFS_LAYOUTRET_ON_ERROR) {
2327		pnfs_return_layout(hdr->inode);
2328	}
2329	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
2330		hdr->task.tk_status = pnfs_read_done_resend_to_mds(hdr);
2331}
2332
2333/*
2334 * Called by non rpc-based layout drivers
2335 */
2336void pnfs_ld_read_done(struct nfs_pgio_header *hdr)
2337{
2338	if (likely(!hdr->pnfs_error))
2339		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
2340	trace_nfs4_pnfs_read(hdr, hdr->pnfs_error);
2341	if (unlikely(hdr->pnfs_error))
2342		pnfs_ld_handle_read_error(hdr);
2343	hdr->mds_ops->rpc_release(hdr);
2344}
2345EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
2346
2347static void
2348pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
2349		struct nfs_pgio_header *hdr)
2350{
2351	struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
2352
2353	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2354		list_splice_tail_init(&hdr->pages, &mirror->pg_list);
2355		nfs_pageio_reset_read_mds(desc);
2356		mirror->pg_recoalesce = 1;
2357	}
2358	nfs_pgio_data_destroy(hdr);
2359	hdr->release(hdr);
2360}
2361
2362/*
2363 * Call the appropriate parallel I/O subsystem read function.
2364 */
2365static enum pnfs_try_status
2366pnfs_try_to_read_data(struct nfs_pgio_header *hdr,
2367		       const struct rpc_call_ops *call_ops,
2368		       struct pnfs_layout_segment *lseg)
2369{
2370	struct inode *inode = hdr->inode;
2371	struct nfs_server *nfss = NFS_SERVER(inode);
2372	enum pnfs_try_status trypnfs;
2373
2374	hdr->mds_ops = call_ops;
 
2375
2376	dprintk("%s: Reading ino:%lu %u@%llu\n",
2377		__func__, inode->i_ino, hdr->args.count, hdr->args.offset);
2378
2379	trypnfs = nfss->pnfs_curr_ld->read_pagelist(hdr);
2380	if (trypnfs != PNFS_NOT_ATTEMPTED)
 
 
 
2381		nfs_inc_stats(inode, NFSIOS_PNFS_READ);
 
2382	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
2383	return trypnfs;
2384}
2385
2386/* Resend all requests through pnfs. */
2387void pnfs_read_resend_pnfs(struct nfs_pgio_header *hdr)
2388{
2389	struct nfs_pageio_descriptor pgio;
2390
2391	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
2392		/* Prevent deadlocks with layoutreturn! */
2393		pnfs_put_lseg(hdr->lseg);
2394		hdr->lseg = NULL;
2395
2396		nfs_pageio_init_read(&pgio, hdr->inode, false,
2397					hdr->completion_ops);
2398		hdr->task.tk_status = nfs_pageio_resend(&pgio, hdr);
2399	}
2400}
2401EXPORT_SYMBOL_GPL(pnfs_read_resend_pnfs);
2402
2403static void
2404pnfs_do_read(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr)
2405{
 
2406	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
2407	struct pnfs_layout_segment *lseg = desc->pg_lseg;
2408	enum pnfs_try_status trypnfs;
2409
2410	trypnfs = pnfs_try_to_read_data(hdr, call_ops, lseg);
2411	if (trypnfs == PNFS_TRY_AGAIN)
2412		pnfs_read_resend_pnfs(hdr);
2413	if (trypnfs == PNFS_NOT_ATTEMPTED || hdr->task.tk_status)
2414		pnfs_read_through_mds(desc, hdr);
2415}
2416
2417static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
2418{
2419	pnfs_put_lseg(hdr->lseg);
2420	nfs_pgio_header_free(hdr);
 
2421}
2422
2423int
2424pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
2425{
2426	struct nfs_pgio_header *hdr;
2427	int ret;
2428
2429	hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
2430	if (!hdr) {
2431		desc->pg_error = -ENOMEM;
2432		return desc->pg_error;
2433	}
2434	nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
2435	hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
2436	ret = nfs_generic_pgio(desc, hdr);
2437	if (!ret)
2438		pnfs_do_read(desc, hdr);
2439	return ret;
2440}
2441EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
2442
2443static void pnfs_clear_layoutcommitting(struct inode *inode)
2444{
2445	unsigned long *bitlock = &NFS_I(inode)->flags;
2446
2447	clear_bit_unlock(NFS_INO_LAYOUTCOMMITTING, bitlock);
2448	smp_mb__after_atomic();
2449	wake_up_bit(bitlock, NFS_INO_LAYOUTCOMMITTING);
2450}
2451
2452/*
2453 * There can be multiple RW segments.
2454 */
2455static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
2456{
2457	struct pnfs_layout_segment *lseg;
2458
2459	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
2460		if (lseg->pls_range.iomode == IOMODE_RW &&
2461		    test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
2462			list_add(&lseg->pls_lc_list, listp);
2463	}
2464}
2465
2466static void pnfs_list_write_lseg_done(struct inode *inode, struct list_head *listp)
2467{
2468	struct pnfs_layout_segment *lseg, *tmp;
2469
2470	/* Matched by references in pnfs_set_layoutcommit */
2471	list_for_each_entry_safe(lseg, tmp, listp, pls_lc_list) {
2472		list_del_init(&lseg->pls_lc_list);
2473		pnfs_put_lseg(lseg);
2474	}
2475
2476	pnfs_clear_layoutcommitting(inode);
2477}
2478
2479void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
2480{
2481	pnfs_layout_io_set_failed(lseg->pls_layout, lseg->pls_range.iomode);
2482}
2483EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
2484
2485void
2486pnfs_set_layoutcommit(struct inode *inode, struct pnfs_layout_segment *lseg,
2487		loff_t end_pos)
2488{
2489	struct nfs_inode *nfsi = NFS_I(inode);
 
2490	bool mark_as_dirty = false;
2491
2492	spin_lock(&inode->i_lock);
2493	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
2494		nfsi->layout->plh_lwb = end_pos;
2495		mark_as_dirty = true;
2496		dprintk("%s: Set layoutcommit for inode %lu ",
2497			__func__, inode->i_ino);
2498	} else if (end_pos > nfsi->layout->plh_lwb)
2499		nfsi->layout->plh_lwb = end_pos;
2500	if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags)) {
2501		/* references matched in nfs4_layoutcommit_release */
2502		pnfs_get_lseg(lseg);
2503	}
2504	spin_unlock(&inode->i_lock);
 
 
2505	dprintk("%s: lseg %p end_pos %llu\n",
2506		__func__, lseg, nfsi->layout->plh_lwb);
2507
2508	/* if pnfs_layoutcommit_inode() runs between inode locks, the next one
2509	 * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */
2510	if (mark_as_dirty)
2511		mark_inode_dirty_sync(inode);
2512}
2513EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
2514
2515void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data)
2516{
2517	struct nfs_server *nfss = NFS_SERVER(data->args.inode);
2518
2519	if (nfss->pnfs_curr_ld->cleanup_layoutcommit)
2520		nfss->pnfs_curr_ld->cleanup_layoutcommit(data);
2521	pnfs_list_write_lseg_done(data->args.inode, &data->lseg_list);
2522}
2523
2524/*
2525 * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
2526 * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
2527 * data to disk to allow the server to recover the data if it crashes.
2528 * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
2529 * is off, and a COMMIT is sent to a data server, or
2530 * if WRITEs to a data server return NFS_DATA_SYNC.
2531 */
2532int
2533pnfs_layoutcommit_inode(struct inode *inode, bool sync)
2534{
2535	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
2536	struct nfs4_layoutcommit_data *data;
2537	struct nfs_inode *nfsi = NFS_I(inode);
2538	loff_t end_pos;
2539	int status;
2540
2541	if (!pnfs_layoutcommit_outstanding(inode))
2542		return 0;
2543
2544	dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
2545
2546	status = -EAGAIN;
2547	if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
2548		if (!sync)
2549			goto out;
2550		status = wait_on_bit_lock_action(&nfsi->flags,
2551				NFS_INO_LAYOUTCOMMITTING,
2552				nfs_wait_bit_killable,
2553				TASK_KILLABLE);
2554		if (status)
2555			goto out;
2556	}
2557
2558	status = -ENOMEM;
2559	/* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
2560	data = kzalloc(sizeof(*data), GFP_NOFS);
2561	if (!data)
2562		goto clear_layoutcommitting;
 
 
 
2563
2564	status = 0;
2565	spin_lock(&inode->i_lock);
2566	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
2567		goto out_unlock;
 
 
 
2568
2569	INIT_LIST_HEAD(&data->lseg_list);
2570	pnfs_list_write_lseg(inode, &data->lseg_list);
2571
2572	end_pos = nfsi->layout->plh_lwb;
 
2573
2574	nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
 
2575	spin_unlock(&inode->i_lock);
2576
2577	data->args.inode = inode;
2578	data->cred = get_rpccred(nfsi->layout->plh_lc_cred);
2579	nfs_fattr_init(&data->fattr);
2580	data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
2581	data->res.fattr = &data->fattr;
2582	if (end_pos != 0)
2583		data->args.lastbytewritten = end_pos - 1;
2584	else
2585		data->args.lastbytewritten = U64_MAX;
2586	data->res.server = NFS_SERVER(inode);
2587
2588	if (ld->prepare_layoutcommit) {
2589		status = ld->prepare_layoutcommit(&data->args);
2590		if (status) {
2591			put_rpccred(data->cred);
2592			spin_lock(&inode->i_lock);
2593			set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags);
2594			if (end_pos > nfsi->layout->plh_lwb)
2595				nfsi->layout->plh_lwb = end_pos;
2596			goto out_unlock;
2597		}
2598	}
2599
2600
2601	status = nfs4_proc_layoutcommit(data, sync);
2602out:
2603	if (status)
2604		mark_inode_dirty_sync(inode);
2605	dprintk("<-- %s status %d\n", __func__, status);
2606	return status;
2607out_unlock:
2608	spin_unlock(&inode->i_lock);
2609	kfree(data);
2610clear_layoutcommitting:
2611	pnfs_clear_layoutcommitting(inode);
2612	goto out;
2613}
2614EXPORT_SYMBOL_GPL(pnfs_layoutcommit_inode);
2615
2616int
2617pnfs_generic_sync(struct inode *inode, bool datasync)
2618{
2619	return pnfs_layoutcommit_inode(inode, true);
2620}
2621EXPORT_SYMBOL_GPL(pnfs_generic_sync);
2622
2623struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
2624{
2625	struct nfs4_threshold *thp;
2626
2627	thp = kzalloc(sizeof(*thp), GFP_NOFS);
2628	if (!thp) {
2629		dprintk("%s mdsthreshold allocation failed\n", __func__);
2630		return NULL;
2631	}
2632	return thp;
2633}
2634
2635#if IS_ENABLED(CONFIG_NFS_V4_2)
2636int
2637pnfs_report_layoutstat(struct inode *inode, gfp_t gfp_flags)
2638{
2639	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
2640	struct nfs_server *server = NFS_SERVER(inode);
2641	struct nfs_inode *nfsi = NFS_I(inode);
2642	struct nfs42_layoutstat_data *data;
2643	struct pnfs_layout_hdr *hdr;
2644	int status = 0;
2645
2646	if (!pnfs_enabled_sb(server) || !ld->prepare_layoutstats)
2647		goto out;
2648
2649	if (!nfs_server_capable(inode, NFS_CAP_LAYOUTSTATS))
2650		goto out;
2651
2652	if (test_and_set_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags))
2653		goto out;
2654
2655	spin_lock(&inode->i_lock);
2656	if (!NFS_I(inode)->layout) {
2657		spin_unlock(&inode->i_lock);
2658		goto out_clear_layoutstats;
2659	}
2660	hdr = NFS_I(inode)->layout;
2661	pnfs_get_layout_hdr(hdr);
2662	spin_unlock(&inode->i_lock);
2663
2664	data = kzalloc(sizeof(*data), gfp_flags);
2665	if (!data) {
2666		status = -ENOMEM;
2667		goto out_put;
2668	}
2669
2670	data->args.fh = NFS_FH(inode);
2671	data->args.inode = inode;
2672	status = ld->prepare_layoutstats(&data->args);
2673	if (status)
2674		goto out_free;
2675
2676	status = nfs42_proc_layoutstats_generic(NFS_SERVER(inode), data);
2677
2678out:
2679	dprintk("%s returns %d\n", __func__, status);
2680	return status;
2681
2682out_free:
2683	kfree(data);
2684out_put:
2685	pnfs_put_layout_hdr(hdr);
2686out_clear_layoutstats:
2687	smp_mb__before_atomic();
2688	clear_bit(NFS_INO_LAYOUTSTATS, &nfsi->flags);
2689	smp_mb__after_atomic();
2690	goto out;
2691}
2692EXPORT_SYMBOL_GPL(pnfs_report_layoutstat);
2693#endif
2694
2695unsigned int layoutstats_timer;
2696module_param(layoutstats_timer, uint, 0644);
2697EXPORT_SYMBOL_GPL(layoutstats_timer);