2 * pNFS functions to call and manage layout drivers.
4 * Copyright (c) 2002 [year of first publication]
5 * The Regents of the University of Michigan
8 * Dean Hildebrand <dhildebz@umich.edu>
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.
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
30 #include <linux/nfs_fs.h>
34 #define NFSDBG_FACILITY NFSDBG_PNFS
39 * protects pnfs_modules_tbl.
41 static DEFINE_SPINLOCK(pnfs_spinlock);
44 * pnfs_modules_tbl holds all pnfs modules
46 static LIST_HEAD(pnfs_modules_tbl);
48 /* Return the registered pnfs layout driver module matching given id */
49 static struct pnfs_layoutdriver_type *
50 find_pnfs_driver_locked(u32 id)
52 struct pnfs_layoutdriver_type *local;
54 list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid)
59 dprintk("%s: Searching for id %u, found %p\n", __func__, id, local);
63 static struct pnfs_layoutdriver_type *
64 find_pnfs_driver(u32 id)
66 struct pnfs_layoutdriver_type *local;
68 spin_lock(&pnfs_spinlock);
69 local = find_pnfs_driver_locked(id);
70 spin_unlock(&pnfs_spinlock);
75 unset_pnfs_layoutdriver(struct nfs_server *nfss)
77 if (nfss->pnfs_curr_ld) {
78 nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
79 module_put(nfss->pnfs_curr_ld->owner);
81 nfss->pnfs_curr_ld = NULL;
85 * Try to set the server's pnfs module to the pnfs layout type specified by id.
86 * Currently only one pNFS layout driver per filesystem is supported.
88 * @id layout type. Zero (illegal layout type) indicates pNFS not in use.
91 set_pnfs_layoutdriver(struct nfs_server *server, u32 id)
93 struct pnfs_layoutdriver_type *ld_type = NULL;
97 if (!(server->nfs_client->cl_exchange_flags &
98 (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
99 printk(KERN_ERR "%s: id %u cl_exchange_flags 0x%x\n", __func__,
100 id, server->nfs_client->cl_exchange_flags);
103 ld_type = find_pnfs_driver(id);
105 request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX, id);
106 ld_type = find_pnfs_driver(id);
108 dprintk("%s: No pNFS module found for %u.\n",
113 if (!try_module_get(ld_type->owner)) {
114 dprintk("%s: Could not grab reference on module\n", __func__);
117 server->pnfs_curr_ld = ld_type;
118 if (ld_type->set_layoutdriver(server)) {
120 "%s: Error initializing mount point for layout driver %u.\n",
122 module_put(ld_type->owner);
125 dprintk("%s: pNFS module for %u set\n", __func__, id);
129 dprintk("%s: Using NFSv4 I/O\n", __func__);
130 server->pnfs_curr_ld = NULL;
134 pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
136 int status = -EINVAL;
137 struct pnfs_layoutdriver_type *tmp;
139 if (ld_type->id == 0) {
140 printk(KERN_ERR "%s id 0 is reserved\n", __func__);
143 if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
144 printk(KERN_ERR "%s Layout driver must provide "
145 "alloc_lseg and free_lseg.\n", __func__);
149 spin_lock(&pnfs_spinlock);
150 tmp = find_pnfs_driver_locked(ld_type->id);
152 list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
154 dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
157 printk(KERN_ERR "%s Module with id %d already loaded!\n",
158 __func__, ld_type->id);
160 spin_unlock(&pnfs_spinlock);
164 EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);
167 pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
169 dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
170 spin_lock(&pnfs_spinlock);
171 list_del(&ld_type->pnfs_tblid);
172 spin_unlock(&pnfs_spinlock);
174 EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
177 * pNFS client layout cache
180 /* Need to hold i_lock if caller does not already hold reference */
182 get_layout_hdr(struct pnfs_layout_hdr *lo)
184 atomic_inc(&lo->plh_refcount);
188 destroy_layout_hdr(struct pnfs_layout_hdr *lo)
190 dprintk("%s: freeing layout cache %p\n", __func__, lo);
191 BUG_ON(!list_empty(&lo->plh_layouts));
192 NFS_I(lo->plh_inode)->layout = NULL;
197 put_layout_hdr_locked(struct pnfs_layout_hdr *lo)
199 if (atomic_dec_and_test(&lo->plh_refcount))
200 destroy_layout_hdr(lo);
204 put_layout_hdr(struct pnfs_layout_hdr *lo)
206 struct inode *inode = lo->plh_inode;
208 if (atomic_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
209 destroy_layout_hdr(lo);
210 spin_unlock(&inode->i_lock);
215 init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg)
217 INIT_LIST_HEAD(&lseg->pls_list);
218 atomic_set(&lseg->pls_refcount, 1);
220 set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
221 lseg->pls_layout = lo;
224 static void free_lseg(struct pnfs_layout_segment *lseg)
226 struct inode *ino = lseg->pls_layout->plh_inode;
228 NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
229 /* Matched by get_layout_hdr in pnfs_insert_layout */
230 put_layout_hdr(NFS_I(ino)->layout);
233 /* The use of tmp_list is necessary because pnfs_curr_ld->free_lseg
234 * could sleep, so must be called outside of the lock.
235 * Returns 1 if object was removed, otherwise return 0.
238 put_lseg_locked(struct pnfs_layout_segment *lseg,
239 struct list_head *tmp_list)
241 dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
242 atomic_read(&lseg->pls_refcount),
243 test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
244 if (atomic_dec_and_test(&lseg->pls_refcount)) {
245 struct inode *ino = lseg->pls_layout->plh_inode;
247 BUG_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
248 list_del(&lseg->pls_list);
249 if (list_empty(&lseg->pls_layout->plh_segs)) {
250 set_bit(NFS_LAYOUT_DESTROYED, &lseg->pls_layout->plh_flags);
251 /* Matched by initial refcount set in alloc_init_layout_hdr */
252 put_layout_hdr_locked(lseg->pls_layout);
254 rpc_wake_up(&NFS_SERVER(ino)->roc_rpcwaitq);
255 list_add(&lseg->pls_list, tmp_list);
262 should_free_lseg(u32 lseg_iomode, u32 recall_iomode)
264 return (recall_iomode == IOMODE_ANY ||
265 lseg_iomode == recall_iomode);
268 /* Returns 1 if lseg is removed from list, 0 otherwise */
269 static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
270 struct list_head *tmp_list)
274 if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
275 /* Remove the reference keeping the lseg in the
276 * list. It will now be removed when all
277 * outstanding io is finished.
279 rv = put_lseg_locked(lseg, tmp_list);
284 /* Returns count of number of matching invalid lsegs remaining in list
288 mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
289 struct list_head *tmp_list,
292 struct pnfs_layout_segment *lseg, *next;
293 int invalid = 0, removed = 0;
295 dprintk("%s:Begin lo %p\n", __func__, lo);
297 if (list_empty(&lo->plh_segs)) {
298 if (!test_and_set_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags))
299 put_layout_hdr_locked(lo);
302 list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
303 if (should_free_lseg(lseg->pls_range.iomode, iomode)) {
304 dprintk("%s: freeing lseg %p iomode %d "
305 "offset %llu length %llu\n", __func__,
306 lseg, lseg->pls_range.iomode, lseg->pls_range.offset,
307 lseg->pls_range.length);
309 removed += mark_lseg_invalid(lseg, tmp_list);
311 dprintk("%s:Return %i\n", __func__, invalid - removed);
312 return invalid - removed;
315 /* note free_me must contain lsegs from a single layout_hdr */
317 pnfs_free_lseg_list(struct list_head *free_me)
319 struct pnfs_layout_segment *lseg, *tmp;
320 struct pnfs_layout_hdr *lo;
322 if (list_empty(free_me))
325 lo = list_first_entry(free_me, struct pnfs_layout_segment,
326 pls_list)->pls_layout;
328 if (test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags)) {
329 struct nfs_client *clp;
331 clp = NFS_SERVER(lo->plh_inode)->nfs_client;
332 spin_lock(&clp->cl_lock);
333 list_del_init(&lo->plh_layouts);
334 spin_unlock(&clp->cl_lock);
336 list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
337 list_del(&lseg->pls_list);
343 pnfs_destroy_layout(struct nfs_inode *nfsi)
345 struct pnfs_layout_hdr *lo;
348 spin_lock(&nfsi->vfs_inode.i_lock);
351 lo->plh_block_lgets++; /* permanently block new LAYOUTGETs */
352 mark_matching_lsegs_invalid(lo, &tmp_list, IOMODE_ANY);
354 spin_unlock(&nfsi->vfs_inode.i_lock);
355 pnfs_free_lseg_list(&tmp_list);
359 * Called by the state manger to remove all layouts established under an
363 pnfs_destroy_all_layouts(struct nfs_client *clp)
365 struct pnfs_layout_hdr *lo;
368 spin_lock(&clp->cl_lock);
369 list_splice_init(&clp->cl_layouts, &tmp_list);
370 spin_unlock(&clp->cl_lock);
372 while (!list_empty(&tmp_list)) {
373 lo = list_entry(tmp_list.next, struct pnfs_layout_hdr,
375 dprintk("%s freeing layout for inode %lu\n", __func__,
376 lo->plh_inode->i_ino);
377 pnfs_destroy_layout(NFS_I(lo->plh_inode));
381 /* update lo->plh_stateid with new if is more recent */
383 pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
388 oldseq = be32_to_cpu(lo->plh_stateid.stateid.seqid);
389 newseq = be32_to_cpu(new->stateid.seqid);
390 if ((int)(newseq - oldseq) > 0) {
391 memcpy(&lo->plh_stateid, &new->stateid, sizeof(new->stateid));
392 if (update_barrier) {
393 u32 new_barrier = be32_to_cpu(new->stateid.seqid);
395 if ((int)(new_barrier - lo->plh_barrier))
396 lo->plh_barrier = new_barrier;
398 /* Because of wraparound, we want to keep the barrier
399 * "close" to the current seqids. It needs to be
400 * within 2**31 to count as "behind", so if it
401 * gets too near that limit, give us a litle leeway
402 * and bring it to within 2**30.
403 * NOTE - and yes, this is all unsigned arithmetic.
405 if (unlikely((newseq - lo->plh_barrier) > (3 << 29)))
406 lo->plh_barrier = newseq - (1 << 30);
411 /* lget is set to 1 if called from inside send_layoutget call chain */
413 pnfs_layoutgets_blocked(struct pnfs_layout_hdr *lo, nfs4_stateid *stateid,
417 (int)(lo->plh_barrier - be32_to_cpu(stateid->stateid.seqid)) >= 0)
419 return lo->plh_block_lgets ||
420 test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags) ||
421 test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
422 (list_empty(&lo->plh_segs) &&
423 (atomic_read(&lo->plh_outstanding) > lget));
427 pnfs_choose_layoutget_stateid(nfs4_stateid *dst, struct pnfs_layout_hdr *lo,
428 struct nfs4_state *open_state)
432 dprintk("--> %s\n", __func__);
433 spin_lock(&lo->plh_inode->i_lock);
434 if (pnfs_layoutgets_blocked(lo, NULL, 1)) {
436 } else if (list_empty(&lo->plh_segs)) {
440 seq = read_seqbegin(&open_state->seqlock);
441 memcpy(dst->data, open_state->stateid.data,
442 sizeof(open_state->stateid.data));
443 } while (read_seqretry(&open_state->seqlock, seq));
445 memcpy(dst->data, lo->plh_stateid.data, sizeof(lo->plh_stateid.data));
446 spin_unlock(&lo->plh_inode->i_lock);
447 dprintk("<-- %s\n", __func__);
452 * Get layout from server.
453 * for now, assume that whole file layouts are requested.
455 * arg->length: all ones
457 static struct pnfs_layout_segment *
458 send_layoutget(struct pnfs_layout_hdr *lo,
459 struct nfs_open_context *ctx,
462 struct inode *ino = lo->plh_inode;
463 struct nfs_server *server = NFS_SERVER(ino);
464 struct nfs4_layoutget *lgp;
465 struct pnfs_layout_segment *lseg = NULL;
467 dprintk("--> %s\n", __func__);
470 lgp = kzalloc(sizeof(*lgp), GFP_KERNEL);
473 lgp->args.minlength = NFS4_MAX_UINT64;
474 lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
475 lgp->args.range.iomode = iomode;
476 lgp->args.range.offset = 0;
477 lgp->args.range.length = NFS4_MAX_UINT64;
478 lgp->args.type = server->pnfs_curr_ld->id;
479 lgp->args.inode = ino;
480 lgp->args.ctx = get_nfs_open_context(ctx);
483 /* Synchronously retrieve layout information from server and
486 nfs4_proc_layoutget(lgp);
488 /* remember that LAYOUTGET failed and suspend trying */
489 set_bit(lo_fail_bit(iomode), &lo->plh_flags);
494 bool pnfs_roc(struct inode *ino)
496 struct pnfs_layout_hdr *lo;
497 struct pnfs_layout_segment *lseg, *tmp;
501 spin_lock(&ino->i_lock);
502 lo = NFS_I(ino)->layout;
503 if (!lo || !test_and_clear_bit(NFS_LAYOUT_ROC, &lo->plh_flags) ||
504 test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags))
506 list_for_each_entry_safe(lseg, tmp, &lo->plh_segs, pls_list)
507 if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
508 mark_lseg_invalid(lseg, &tmp_list);
513 lo->plh_block_lgets++;
514 get_layout_hdr(lo); /* matched in pnfs_roc_release */
515 spin_unlock(&ino->i_lock);
516 pnfs_free_lseg_list(&tmp_list);
520 spin_unlock(&ino->i_lock);
524 void pnfs_roc_release(struct inode *ino)
526 struct pnfs_layout_hdr *lo;
528 spin_lock(&ino->i_lock);
529 lo = NFS_I(ino)->layout;
530 lo->plh_block_lgets--;
531 put_layout_hdr_locked(lo);
532 spin_unlock(&ino->i_lock);
535 void pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
537 struct pnfs_layout_hdr *lo;
539 spin_lock(&ino->i_lock);
540 lo = NFS_I(ino)->layout;
541 if ((int)(barrier - lo->plh_barrier) > 0)
542 lo->plh_barrier = barrier;
543 spin_unlock(&ino->i_lock);
546 bool pnfs_roc_drain(struct inode *ino, u32 *barrier)
548 struct nfs_inode *nfsi = NFS_I(ino);
549 struct pnfs_layout_segment *lseg;
552 spin_lock(&ino->i_lock);
553 list_for_each_entry(lseg, &nfsi->layout->plh_segs, pls_list)
554 if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
559 struct pnfs_layout_hdr *lo = nfsi->layout;
560 u32 current_seqid = be32_to_cpu(lo->plh_stateid.stateid.seqid);
562 /* Since close does not return a layout stateid for use as
563 * a barrier, we choose the worst-case barrier.
565 *barrier = current_seqid + atomic_read(&lo->plh_outstanding);
567 spin_unlock(&ino->i_lock);
572 * Compare two layout segments for sorting into layout cache.
573 * We want to preferentially return RW over RO layouts, so ensure those
577 cmp_layout(u32 iomode1, u32 iomode2)
579 /* read > read/write */
580 return (int)(iomode2 == IOMODE_READ) - (int)(iomode1 == IOMODE_READ);
584 pnfs_insert_layout(struct pnfs_layout_hdr *lo,
585 struct pnfs_layout_segment *lseg)
587 struct pnfs_layout_segment *lp;
590 dprintk("%s:Begin\n", __func__);
592 assert_spin_locked(&lo->plh_inode->i_lock);
593 list_for_each_entry(lp, &lo->plh_segs, pls_list) {
594 if (cmp_layout(lp->pls_range.iomode, lseg->pls_range.iomode) > 0)
596 list_add_tail(&lseg->pls_list, &lp->pls_list);
597 dprintk("%s: inserted lseg %p "
598 "iomode %d offset %llu length %llu before "
599 "lp %p iomode %d offset %llu length %llu\n",
600 __func__, lseg, lseg->pls_range.iomode,
601 lseg->pls_range.offset, lseg->pls_range.length,
602 lp, lp->pls_range.iomode, lp->pls_range.offset,
603 lp->pls_range.length);
608 list_add_tail(&lseg->pls_list, &lo->plh_segs);
609 dprintk("%s: inserted lseg %p "
610 "iomode %d offset %llu length %llu at tail\n",
611 __func__, lseg, lseg->pls_range.iomode,
612 lseg->pls_range.offset, lseg->pls_range.length);
616 dprintk("%s:Return\n", __func__);
619 static struct pnfs_layout_hdr *
620 alloc_init_layout_hdr(struct inode *ino)
622 struct pnfs_layout_hdr *lo;
624 lo = kzalloc(sizeof(struct pnfs_layout_hdr), GFP_KERNEL);
627 atomic_set(&lo->plh_refcount, 1);
628 INIT_LIST_HEAD(&lo->plh_layouts);
629 INIT_LIST_HEAD(&lo->plh_segs);
630 INIT_LIST_HEAD(&lo->plh_bulk_recall);
635 static struct pnfs_layout_hdr *
636 pnfs_find_alloc_layout(struct inode *ino)
638 struct nfs_inode *nfsi = NFS_I(ino);
639 struct pnfs_layout_hdr *new = NULL;
641 dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
643 assert_spin_locked(&ino->i_lock);
645 if (test_bit(NFS_LAYOUT_DESTROYED, &nfsi->layout->plh_flags))
650 spin_unlock(&ino->i_lock);
651 new = alloc_init_layout_hdr(ino);
652 spin_lock(&ino->i_lock);
654 if (likely(nfsi->layout == NULL)) /* Won the race? */
662 * iomode matching rules:
673 is_matching_lseg(struct pnfs_layout_segment *lseg, u32 iomode)
675 return (iomode != IOMODE_RW || lseg->pls_range.iomode == IOMODE_RW);
679 * lookup range in layout
681 static struct pnfs_layout_segment *
682 pnfs_find_lseg(struct pnfs_layout_hdr *lo, u32 iomode)
684 struct pnfs_layout_segment *lseg, *ret = NULL;
686 dprintk("%s:Begin\n", __func__);
688 assert_spin_locked(&lo->plh_inode->i_lock);
689 list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
690 if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
691 is_matching_lseg(lseg, iomode)) {
695 if (cmp_layout(iomode, lseg->pls_range.iomode) > 0)
699 dprintk("%s:Return lseg %p ref %d\n",
700 __func__, ret, ret ? atomic_read(&ret->pls_refcount) : 0);
705 * Layout segment is retreived from the server if not cached.
706 * The appropriate layout segment is referenced and returned to the caller.
708 struct pnfs_layout_segment *
709 pnfs_update_layout(struct inode *ino,
710 struct nfs_open_context *ctx,
711 enum pnfs_iomode iomode)
713 struct nfs_inode *nfsi = NFS_I(ino);
714 struct nfs_client *clp = NFS_SERVER(ino)->nfs_client;
715 struct pnfs_layout_hdr *lo;
716 struct pnfs_layout_segment *lseg = NULL;
719 if (!pnfs_enabled_sb(NFS_SERVER(ino)))
721 spin_lock(&ino->i_lock);
722 lo = pnfs_find_alloc_layout(ino);
724 dprintk("%s ERROR: can't get pnfs_layout_hdr\n", __func__);
728 /* Do we even need to bother with this? */
729 if (test_bit(NFS4CLNT_LAYOUTRECALL, &clp->cl_state) ||
730 test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
731 dprintk("%s matches recall, use MDS\n", __func__);
734 /* Check to see if the layout for the given range already exists */
735 lseg = pnfs_find_lseg(lo, iomode);
739 /* if LAYOUTGET already failed once we don't try again */
740 if (test_bit(lo_fail_bit(iomode), &nfsi->layout->plh_flags))
743 if (pnfs_layoutgets_blocked(lo, NULL, 0))
745 atomic_inc(&lo->plh_outstanding);
748 if (list_empty(&lo->plh_segs))
750 spin_unlock(&ino->i_lock);
752 /* The lo must be on the clp list if there is any
753 * chance of a CB_LAYOUTRECALL(FILE) coming in.
755 spin_lock(&clp->cl_lock);
756 BUG_ON(!list_empty(&lo->plh_layouts));
757 list_add_tail(&lo->plh_layouts, &clp->cl_layouts);
758 spin_unlock(&clp->cl_lock);
761 lseg = send_layoutget(lo, ctx, iomode);
762 if (!lseg && first) {
763 spin_lock(&clp->cl_lock);
764 list_del_init(&lo->plh_layouts);
765 spin_unlock(&clp->cl_lock);
767 atomic_dec(&lo->plh_outstanding);
770 dprintk("%s end, state 0x%lx lseg %p\n", __func__,
771 nfsi->layout->plh_flags, lseg);
774 spin_unlock(&ino->i_lock);
779 pnfs_layout_process(struct nfs4_layoutget *lgp)
781 struct pnfs_layout_hdr *lo = NFS_I(lgp->args.inode)->layout;
782 struct nfs4_layoutget_res *res = &lgp->res;
783 struct pnfs_layout_segment *lseg;
784 struct inode *ino = lo->plh_inode;
785 struct nfs_client *clp = NFS_SERVER(ino)->nfs_client;
788 /* Verify we got what we asked for.
789 * Note that because the xdr parsing only accepts a single
790 * element array, this can fail even if the server is behaving
793 if (lgp->args.range.iomode > res->range.iomode ||
794 res->range.offset != 0 ||
795 res->range.length != NFS4_MAX_UINT64) {
799 /* Inject layout blob into I/O device driver */
800 lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res);
801 if (!lseg || IS_ERR(lseg)) {
805 status = PTR_ERR(lseg);
806 dprintk("%s: Could not allocate layout: error %d\n",
811 spin_lock(&ino->i_lock);
812 if (test_bit(NFS4CLNT_LAYOUTRECALL, &clp->cl_state) ||
813 test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
814 dprintk("%s forget reply due to recall\n", __func__);
815 goto out_forget_reply;
818 if (pnfs_layoutgets_blocked(lo, &res->stateid, 1)) {
819 dprintk("%s forget reply due to state\n", __func__);
820 goto out_forget_reply;
823 lseg->pls_range = res->range;
825 pnfs_insert_layout(lo, lseg);
827 if (res->return_on_close) {
828 set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
829 set_bit(NFS_LAYOUT_ROC, &lo->plh_flags);
832 /* Done processing layoutget. Set the layout stateid */
833 pnfs_set_layout_stateid(lo, &res->stateid, false);
834 spin_unlock(&ino->i_lock);
839 spin_unlock(&ino->i_lock);
840 lseg->pls_layout = lo;
841 NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
846 * Device ID cache. Currently supports one layout type per struct nfs_client.
847 * Add layout type to the lookup key to expand to support multiple types.
850 pnfs_alloc_init_deviceid_cache(struct nfs_client *clp,
851 void (*free_callback)(struct pnfs_deviceid_node *))
853 struct pnfs_deviceid_cache *c;
855 c = kzalloc(sizeof(struct pnfs_deviceid_cache), GFP_KERNEL);
858 spin_lock(&clp->cl_lock);
859 if (clp->cl_devid_cache != NULL) {
860 atomic_inc(&clp->cl_devid_cache->dc_ref);
861 dprintk("%s [kref [%d]]\n", __func__,
862 atomic_read(&clp->cl_devid_cache->dc_ref));
865 /* kzalloc initializes hlists */
866 spin_lock_init(&c->dc_lock);
867 atomic_set(&c->dc_ref, 1);
868 c->dc_free_callback = free_callback;
869 clp->cl_devid_cache = c;
870 dprintk("%s [new]\n", __func__);
872 spin_unlock(&clp->cl_lock);
875 EXPORT_SYMBOL_GPL(pnfs_alloc_init_deviceid_cache);
878 * Called from pnfs_layoutdriver_type->free_lseg
879 * last layout segment reference frees deviceid
882 pnfs_put_deviceid(struct pnfs_deviceid_cache *c,
883 struct pnfs_deviceid_node *devid)
885 struct nfs4_deviceid *id = &devid->de_id;
886 struct pnfs_deviceid_node *d;
887 struct hlist_node *n;
888 long h = nfs4_deviceid_hash(id);
890 dprintk("%s [%d]\n", __func__, atomic_read(&devid->de_ref));
891 if (!atomic_dec_and_lock(&devid->de_ref, &c->dc_lock))
894 hlist_for_each_entry_rcu(d, n, &c->dc_deviceids[h], de_node)
895 if (!memcmp(&d->de_id, id, sizeof(*id))) {
896 hlist_del_rcu(&d->de_node);
897 spin_unlock(&c->dc_lock);
899 c->dc_free_callback(devid);
902 spin_unlock(&c->dc_lock);
903 /* Why wasn't it found in the list? */
906 EXPORT_SYMBOL_GPL(pnfs_put_deviceid);
908 /* Find and reference a deviceid */
909 struct pnfs_deviceid_node *
910 pnfs_find_get_deviceid(struct pnfs_deviceid_cache *c, struct nfs4_deviceid *id)
912 struct pnfs_deviceid_node *d;
913 struct hlist_node *n;
914 long hash = nfs4_deviceid_hash(id);
916 dprintk("--> %s hash %ld\n", __func__, hash);
918 hlist_for_each_entry_rcu(d, n, &c->dc_deviceids[hash], de_node) {
919 if (!memcmp(&d->de_id, id, sizeof(*id))) {
920 if (!atomic_inc_not_zero(&d->de_ref)) {
932 EXPORT_SYMBOL_GPL(pnfs_find_get_deviceid);
935 * Add a deviceid to the cache.
936 * GETDEVICEINFOs for same deviceid can race. If deviceid is found, discard new
938 struct pnfs_deviceid_node *
939 pnfs_add_deviceid(struct pnfs_deviceid_cache *c, struct pnfs_deviceid_node *new)
941 struct pnfs_deviceid_node *d;
942 long hash = nfs4_deviceid_hash(&new->de_id);
944 dprintk("--> %s hash %ld\n", __func__, hash);
945 spin_lock(&c->dc_lock);
946 d = pnfs_find_get_deviceid(c, &new->de_id);
948 spin_unlock(&c->dc_lock);
949 dprintk("%s [discard]\n", __func__);
950 c->dc_free_callback(new);
953 INIT_HLIST_NODE(&new->de_node);
954 atomic_set(&new->de_ref, 1);
955 hlist_add_head_rcu(&new->de_node, &c->dc_deviceids[hash]);
956 spin_unlock(&c->dc_lock);
957 dprintk("%s [new]\n", __func__);
960 EXPORT_SYMBOL_GPL(pnfs_add_deviceid);
963 pnfs_put_deviceid_cache(struct nfs_client *clp)
965 struct pnfs_deviceid_cache *local = clp->cl_devid_cache;
967 dprintk("--> %s ({%d})\n", __func__, atomic_read(&local->dc_ref));
968 if (atomic_dec_and_lock(&local->dc_ref, &clp->cl_lock)) {
970 /* Verify cache is empty */
971 for (i = 0; i < NFS4_DEVICE_ID_HASH_SIZE; i++)
972 BUG_ON(!hlist_empty(&local->dc_deviceids[i]));
973 clp->cl_devid_cache = NULL;
974 spin_unlock(&clp->cl_lock);
978 EXPORT_SYMBOL_GPL(pnfs_put_deviceid_cache);