aboutsummaryrefslogtreecommitdiff
path: root/fs/nfs/objlayout/objlayout.c
blob: 765d3f54e9860b18404dea42a757f899966ccda8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
/*
 *  pNFS Objects layout driver high level definitions
 *
 *  Copyright (C) 2007 Panasas Inc. [year of first publication]
 *  All rights reserved.
 *
 *  Benny Halevy <bhalevy@panasas.com>
 *  Boaz Harrosh <bharrosh@panasas.com>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2
 *  See the file COPYING included with this distribution for more details.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *  3. Neither the name of the Panasas company nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
 *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <linux/kmod.h>
#include <linux/moduleparam.h>
#include <linux/ratelimit.h>
#include <scsi/osd_initiator.h>
#include "objlayout.h"

#define NFSDBG_FACILITY         NFSDBG_PNFS_LD
/*
 * Create a objlayout layout structure for the given inode and return it.
 */
struct pnfs_layout_hdr *
objlayout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
{
	struct objlayout *objlay;

	objlay = kzalloc(sizeof(struct objlayout), gfp_flags);
	if (!objlay)
		return NULL;
	spin_lock_init(&objlay->lock);
	INIT_LIST_HEAD(&objlay->err_list);
	dprintk("%s: Return %p\n", __func__, objlay);
	return &objlay->pnfs_layout;
}

/*
 * Free an objlayout layout structure
 */
void
objlayout_free_layout_hdr(struct pnfs_layout_hdr *lo)
{
	struct objlayout *objlay = OBJLAYOUT(lo);

	dprintk("%s: objlay %p\n", __func__, objlay);

	WARN_ON(!list_empty(&objlay->err_list));
	kfree(objlay);
}

/*
 * Unmarshall layout and store it in pnfslay.
 */
struct pnfs_layout_segment *
objlayout_alloc_lseg(struct pnfs_layout_hdr *pnfslay,
		     struct nfs4_layoutget_res *lgr,
		     gfp_t gfp_flags)
{
	int status = -ENOMEM;
	struct xdr_stream stream;
	struct xdr_buf buf = {
		.pages =  lgr->layoutp->pages,
		.page_len =  lgr->layoutp->len,
		.buflen =  lgr->layoutp->len,
		.len = lgr->layoutp->len,
	};
	struct page *scratch;
	struct pnfs_layout_segment *lseg;

	dprintk("%s: Begin pnfslay %p\n", __func__, pnfslay);

	scratch = alloc_page(gfp_flags);
	if (!scratch)
		goto err_nofree;

	xdr_init_decode(&stream, &buf, NULL);
	xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);

	status = objio_alloc_lseg(&lseg, pnfslay, &lgr->range, &stream, gfp_flags);
	if (unlikely(status)) {
		dprintk("%s: objio_alloc_lseg Return err %d\n", __func__,
			status);
		goto err;
	}

	__free_page(scratch);

	dprintk("%s: Return %p\n", __func__, lseg);
	return lseg;

err:
	__free_page(scratch);
err_nofree:
	dprintk("%s: Err Return=>%d\n", __func__, status);
	return ERR_PTR(status);
}

/*
 * Free a layout segement
 */
void
objlayout_free_lseg(struct pnfs_layout_segment *lseg)
{
	dprintk("%s: freeing layout segment %p\n", __func__, lseg);

	if (unlikely(!lseg))
		return;

	objio_free_lseg(lseg);
}

/*
 * I/O Operations
 */
static inline u64
end_offset(u64 start, u64 len)
{
	u64 end;

	end = start + len;
	return end >= start ? end : NFS4_MAX_UINT64;
}

static void _fix_verify_io_params(struct pnfs_layout_segment *lseg,
			   struct page ***p_pages, unsigned *p_pgbase,
			   u64 offset, unsigned long count)
{
	u64 lseg_end_offset;

	BUG_ON(offset < lseg->pls_range.offset);
	lseg_end_offset = end_offset(lseg->pls_range.offset,
				     lseg->pls_range.length);
	BUG_ON(offset >= lseg_end_offset);
	WARN_ON(offset + count > lseg_end_offset);

	if (*p_pgbase > PAGE_SIZE) {
		dprintk("%s: pgbase(0x%x) > PAGE_SIZE\n", __func__, *p_pgbase);
		*p_pages += *p_pgbase >> PAGE_SHIFT;
		*p_pgbase &= ~PAGE_MASK;
	}
}

/*
 * I/O done common code
 */
static void
objlayout_iodone(struct objlayout_io_res *oir)
{
	if (likely(oir->status >= 0)) {
		objio_free_result(oir);
	} else {
		struct objlayout *objlay = oir->objlay;

		spin_lock(&objlay->lock);
		objlay->delta_space_valid = OBJ_DSU_INVALID;
		list_add(&objlay->err_list, &oir->err_list);
		spin_unlock(&objlay->lock);
	}
}

/*
 * objlayout_io_set_result - Set an osd_error code on a specific osd comp.
 *
 * The @index component IO failed (error returned from target). Register
 * the error for later reporting at layout-return.
 */
void
objlayout_io_set_result(struct objlayout_io_res *oir, unsigned index,
			struct pnfs_osd_objid *pooid, int osd_error,
			u64 offset, u64 length, bool is_write)
{
	struct pnfs_osd_ioerr *ioerr = &oir->ioerrs[index];

	BUG_ON(index >= oir->num_comps);
	if (osd_error) {
		ioerr->oer_component = *pooid;
		ioerr->oer_comp_offset = offset;
		ioerr->oer_comp_length = length;
		ioerr->oer_iswrite = is_write;
		ioerr->oer_errno = osd_error;

		dprintk("%s: err[%d]: errno=%d is_write=%d dev(%llx:%llx) "
			"par=0x%llx obj=0x%llx offset=0x%llx length=0x%llx\n",
			__func__, index, ioerr->oer_errno,
			ioerr->oer_iswrite,
			_DEVID_LO(&ioerr->oer_component.oid_device_id),
			_DEVID_HI(&ioerr->oer_component.oid_device_id),
			ioerr->oer_component.oid_partition_id,
			ioerr->oer_component.oid_object_id,
			ioerr->oer_comp_offset,
			ioerr->oer_comp_length);
	} else {
		/* User need not call if no error is reported */
		ioerr->oer_errno = 0;
	}
}

/* Function scheduled on rpc workqueue to call ->nfs_readlist_complete().
 * This is because the osd completion is called with ints-off from
 * the block layer
 */
static void _rpc_read_complete(struct work_struct *work)
{
	struct rpc_task *task;
	struct nfs_pgio_data *rdata;

	dprintk("%s enter\n", __func__);
	task = container_of(work, struct rpc_task, u.tk_work);
	rdata = container_of(task, struct nfs_pgio_data, task);

	pnfs_ld_read_done(rdata);
}

void
objlayout_read_done(struct objlayout_io_res *oir, ssize_t status, bool sync)
{
	struct nfs_pgio_data *rdata = oir->rpcdata;

	oir->status = rdata->task.tk_status = status;
	if (status >= 0)
		rdata->res.count = status;
	else
		rdata->header->pnfs_error = status;
	objlayout_iodone(oir);
	/* must not use oir after this point */

	dprintk("%s: Return status=%zd eof=%d sync=%d\n", __func__,
		status, rdata->res.eof, sync);

	if (sync)
		pnfs_ld_read_done(rdata);
	else {
		INIT_WORK(&rdata->task.u.tk_work, _rpc_read_complete);
		schedule_work(&rdata->task.u.tk_work);
	}
}

/*
 * Perform sync or async reads.
 */
enum pnfs_try_status
objlayout_read_pagelist(struct nfs_pgio_data *rdata)
{
	struct nfs_pgio_header *hdr = rdata->header;
	struct inode *inode = hdr->inode;
	loff_t offset = rdata->args.offset;
	size_t count = rdata->args.count;
	int err;
	loff_t eof;

	eof = i_size_read(inode);
	if (unlikely(offset + count > eof)) {
		if (offset >= eof) {
			err = 0;
			rdata->res.count = 0;
			rdata->res.eof = 1;
			/*FIXME: do we need to call pnfs_ld_read_done() */
			goto out;
		}
		count = eof - offset;
	}

	rdata->res.eof = (offset + count) >= eof;
	_fix_verify_io_params(hdr->lseg, &rdata->args.pages,
			      &rdata->args.pgbase,
			      rdata->args.offset, rdata->args.count);

	dprintk("%s: inode(%lx) offset 0x%llx count 0x%Zx eof=%d\n",
		__func__, inode->i_ino, offset, count, rdata->res.eof);

	err = objio_read_pagelist(rdata);
 out:
	if (unlikely(err)) {
		hdr->pnfs_error = err;
		dprintk("%s: Returned Error %d\n", __func__, err);
		return PNFS_NOT_ATTEMPTED;
	}
	return PNFS_ATTEMPTED;
}

/* Function scheduled on rpc workqueue to call ->nfs_writelist_complete().
 * This is because the osd completion is called with ints-off from
 * the block layer
 */
static void _rpc_write_complete(struct work_struct *work)
{
	struct rpc_task *task;
	struct nfs_pgio_data *wdata;

	dprintk("%s enter\n", __func__);
	task = container_of(work, struct rpc_task, u.tk_work);
	wdata = container_of(task, struct nfs_pgio_data, task);

	pnfs_ld_write_done(wdata);
}

void
objlayout_write_done(struct objlayout_io_res *oir, ssize_t status, bool sync)
{
	struct nfs_pgio_data *wdata = oir->rpcdata;

	oir->status = wdata->task.tk_status = status;
	if (status >= 0) {
		wdata->res.count = status;
		wdata->verf.committed = oir->committed;
	} else {
		wdata->header->pnfs_error = status;
	}
	objlayout_iodone(oir);
	/* must not use oir after this point */

	dprintk("%s: Return status %zd committed %d sync=%d\n", __func__,
		status, wdata->verf.committed, sync);

	if (sync)
		pnfs_ld_write_done(wdata);
	else {
		INIT_WORK(&wdata->task.u.tk_work, _rpc_write_complete);
		schedule_work(&wdata->task.u.tk_work);
	}
}

/*
 * Perform sync or async writes.
 */
enum pnfs_try_status
objlayout_write_pagelist(struct nfs_pgio_data *wdata,
			 int how)
{
	struct nfs_pgio_header *hdr = wdata->header;
	int err;

	_fix_verify_io_params(hdr->lseg, &wdata->args.pages,
			      &wdata->args.pgbase,
			      wdata->args.offset, wdata->args.count);

	err = objio_write_pagelist(wdata, how);
	if (unlikely(err)) {
		hdr->pnfs_error = err;
		dprintk("%s: Returned Error %d\n", __func__, err);
		return PNFS_NOT_ATTEMPTED;
	}
	return PNFS_ATTEMPTED;
}

void
objlayout_encode_layoutcommit(struct pnfs_layout_hdr *pnfslay,
			      struct xdr_stream *xdr,
			      const struct nfs4_layoutcommit_args *args)
{
	struct objlayout *objlay = OBJLAYOUT(pnfslay);
	struct pnfs_osd_layoutupdate lou;
	__be32 *start;

	dprintk("%s: Begin\n", __func__);

	spin_lock(&objlay->lock);
	lou.dsu_valid = (objlay->delta_space_valid == OBJ_DSU_VALID);
	lou.dsu_delta = objlay->delta_space_used;
	objlay->delta_space_used = 0;
	objlay->delta_space_valid = OBJ_DSU_INIT;
	lou.olu_ioerr_flag = !list_empty(&objlay->err_list);
	spin_unlock(&objlay->lock);

	start = xdr_reserve_space(xdr, 4);

	BUG_ON(pnfs_osd_xdr_encode_layoutupdate(xdr, &lou));

	*start = cpu_to_be32((xdr->p - start - 1) * 4);

	dprintk("%s: Return delta_space_used %lld err %d\n", __func__,
		lou.dsu_delta, lou.olu_ioerr_flag);
}

static int
err_prio(u32 oer_errno)
{
	switch (oer_errno) {
	case 0:
		return 0;

	case PNFS_OSD_ERR_RESOURCE:
		return OSD_ERR_PRI_RESOURCE;
	case PNFS_OSD_ERR_BAD_CRED:
		return OSD_ERR_PRI_BAD_CRED;
	case PNFS_OSD_ERR_NO_ACCESS:
		return OSD_ERR_PRI_NO_ACCESS;
	case PNFS_OSD_ERR_UNREACHABLE:
		return OSD_ERR_PRI_UNREACHABLE;
	case PNFS_OSD_ERR_NOT_FOUND:
		return OSD_ERR_PRI_NOT_FOUND;
	case PNFS_OSD_ERR_NO_SPACE:
		return OSD_ERR_PRI_NO_SPACE;
	default:
		WARN_ON(1);
		/* fallthrough */
	case PNFS_OSD_ERR_EIO:
		return OSD_ERR_PRI_EIO;
	}
}

static void
merge_ioerr(struct pnfs_osd_ioerr *dest_err,
	    const struct pnfs_osd_ioerr *src_err)
{
	u64 dest_end, src_end;

	if (!dest_err->oer_errno) {
		*dest_err = *src_err;
		/* accumulated device must be blank */
		memset(&dest_err->oer_component.oid_device_id, 0,
			sizeof(dest_err->oer_component.oid_device_id));

		return;
	}

	if (dest_err->oer_component.oid_partition_id !=
				src_err->oer_component.oid_partition_id)
		dest_err->oer_component.oid_partition_id = 0;

	if (dest_err->oer_component.oid_object_id !=
				src_err->oer_component.oid_object_id)
		dest_err->oer_component.oid_object_id = 0;

	if (dest_err->oer_comp_offset > src_err->oer_comp_offset)
		dest_err->oer_comp_offset = src_err->oer_comp_offset;

	dest_end = end_offset(dest_err->oer_comp_offset,
			      dest_err->oer_comp_length);
	src_end =  end_offset(src_err->oer_comp_offset,
			      src_err->oer_comp_length);
	if (dest_end < src_end)
		dest_end = src_end;

	dest_err->oer_comp_length = dest_end - dest_err->oer_comp_offset;

	if ((src_err->oer_iswrite == dest_err->oer_iswrite) &&
	    (err_prio(src_err->oer_errno) > err_prio(dest_err->oer_errno))) {
			dest_err->oer_errno = src_err->oer_errno;
	} else if (src_err->oer_iswrite) {
		dest_err->oer_iswrite = true;
		dest_err->oer_errno = src_err->oer_errno;
	}
}

static void
encode_accumulated_error(struct objlayout *objlay, __be32 *p)
{
	struct objlayout_io_res *oir, *tmp;
	struct pnfs_osd_ioerr accumulated_err = {.oer_errno = 0};

	list_for_each_entry_safe(oir, tmp, &objlay->err_list, err_list) {
		unsigned i;

		for (i = 0; i < oir->num_comps; i++) {
			struct pnfs_osd_ioerr *ioerr = &oir->ioerrs[i];

			if (!ioerr->oer_errno)
				continue;

			printk(KERN_ERR "NFS: %s: err[%d]: errno=%d "
				"is_write=%d dev(%llx:%llx) par=0x%llx "
				"obj=0x%llx offset=0x%llx length=0x%llx\n",
				__func__, i, ioerr->oer_errno,
				ioerr->oer_iswrite,
				_DEVID_LO(&ioerr->oer_component.oid_device_id),
				_DEVID_HI(&ioerr->oer_component.oid_device_id),
				ioerr->oer_component.oid_partition_id,
				ioerr->oer_component.oid_object_id,
				ioerr->oer_comp_offset,
				ioerr->oer_comp_length);

			merge_ioerr(&accumulated_err, ioerr);
		}
		list_del(&oir->err_list);
		objio_free_result(oir);
	}

	pnfs_osd_xdr_encode_ioerr(p, &accumulated_err);
}

void
objlayout_encode_layoutreturn(struct pnfs_layout_hdr *pnfslay,
			      struct xdr_stream *xdr,
			      const struct nfs4_layoutreturn_args *args)
{
	struct objlayout *objlay = OBJLAYOUT(pnfslay);
	struct objlayout_io_res *oir, *tmp;
	__be32 *start;

	dprintk("%s: Begin\n", __func__);
	start = xdr_reserve_space(xdr, 4);
	BUG_ON(!start);

	spin_lock(&objlay->lock);

	list_for_each_entry_safe(oir, tmp, &objlay->err_list, err_list) {
		__be32 *last_xdr = NULL, *p;
		unsigned i;
		int res = 0;

		for (i = 0; i < oir->num_comps; i++) {
			struct pnfs_osd_ioerr *ioerr = &oir->ioerrs[i];

			if (!ioerr->oer_errno)
				continue;

			dprintk("%s: err[%d]: errno=%d is_write=%d "
				"dev(%llx:%llx) par=0x%llx obj=0x%llx "
				"offset=0x%llx length=0x%llx\n",
				__func__, i, ioerr->oer_errno,
				ioerr->oer_iswrite,
				_DEVID_LO(&ioerr->oer_component.oid_device_id),
				_DEVID_HI(&ioerr->oer_component.oid_device_id),
				ioerr->oer_component.oid_partition_id,
				ioerr->oer_component.oid_object_id,
				ioerr->oer_comp_offset,
				ioerr->oer_comp_length);

			p = pnfs_osd_xdr_ioerr_reserve_space(xdr);
			if (unlikely(!p)) {
				res = -E2BIG;
				break; /* accumulated_error */
			}

			last_xdr = p;
			pnfs_osd_xdr_encode_ioerr(p, &oir->ioerrs[i]);
		}

		/* TODO: use xdr_write_pages */
		if (unlikely(res)) {
			/* no space for even one error descriptor */
			BUG_ON(!last_xdr);

			/* we've encountered a situation with lots and lots of
			 * errors and no space to encode them all. Use the last
			 * available slot to report the union of all the
			 * remaining errors.
			 */
			encode_accumulated_error(objlay, last_xdr);
			goto loop_done;
		}
		list_del(&oir->err_list);
		objio_free_result(oir);
	}
loop_done:
	spin_unlock(&objlay->lock);

	*start = cpu_to_be32((xdr->p - start - 1) * 4);
	dprintk("%s: Return\n", __func__);
}


/*
 * Get Device Info API for io engines
 */
struct objlayout_deviceinfo {
	struct page *page;
	struct pnfs_osd_deviceaddr da; /* This must be last */
};

/* Initialize and call nfs_getdeviceinfo, then decode and return a
 * "struct pnfs_osd_deviceaddr *" Eventually objlayout_put_deviceinfo()
 * should be called.
 */
int objlayout_get_deviceinfo(struct pnfs_layout_hdr *pnfslay,
	struct nfs4_deviceid *d_id, struct pnfs_osd_deviceaddr **deviceaddr,
	gfp_t gfp_flags)
{
	struct objlayout_deviceinfo *odi;
	struct pnfs_device pd;
	struct page *page, **pages;
	u32 *p;
	int err;

	page = alloc_page(gfp_flags);
	if (!page)
		return -ENOMEM;

	pages = &page;
	pd.pages = pages;

	memcpy(&pd.dev_id, d_id, sizeof(*d_id));
	pd.layout_type = LAYOUT_OSD2_OBJECTS;
	pd.pages = &page;
	pd.pgbase = 0;
	pd.pglen = PAGE_SIZE;
	pd.mincount = 0;
	pd.maxcount = PAGE_SIZE;

	err = nfs4_proc_getdeviceinfo(NFS_SERVER(pnfslay->plh_inode), &pd,
			pnfslay->plh_lc_cred);
	dprintk("%s nfs_getdeviceinfo returned %d\n", __func__, err);
	if (err)
		goto err_out;

	p = page_address(page);
	odi = kzalloc(sizeof(*odi), gfp_flags);
	if (!odi) {
		err = -ENOMEM;
		goto err_out;
	}
	pnfs_osd_xdr_decode_deviceaddr(&odi->da, p);
	odi->page = page;
	*deviceaddr = &odi->da;
	return 0;

err_out:
	__free_page(page);
	return err;
}

void objlayout_put_deviceinfo(struct pnfs_osd_deviceaddr *deviceaddr)
{
	struct objlayout_deviceinfo *odi = container_of(deviceaddr,
						struct objlayout_deviceinfo,
						da);

	__free_page(odi->page);
	kfree(odi);
}

enum {
	OBJLAYOUT_MAX_URI_LEN = 256, OBJLAYOUT_MAX_OSDNAME_LEN = 64,
	OBJLAYOUT_MAX_SYSID_HEX_LEN = OSD_SYSTEMID_LEN * 2 + 1,
	OSD_LOGIN_UPCALL_PATHLEN  = 256
};

static char osd_login_prog[OSD_LOGIN_UPCALL_PATHLEN] = "/sbin/osd_login";

module_param_string(osd_login_prog, osd_login_prog, sizeof(osd_login_prog),
		    0600);
MODULE_PARM_DESC(osd_login_prog, "Path to the osd_login upcall program");

struct __auto_login {
	char uri[OBJLAYOUT_MAX_URI_LEN];
	char osdname[OBJLAYOUT_MAX_OSDNAME_LEN];
	char systemid_hex[OBJLAYOUT_MAX_SYSID_HEX_LEN];
};

static int __objlayout_upcall(struct __auto_login *login)
{
	static char *envp[] = { "HOME=/",
		"TERM=linux",
		"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
		NULL
	};
	char *argv[8];
	int ret;

	if (unlikely(!osd_login_prog[0])) {
		dprintk("%s: osd_login_prog is disabled\n", __func__);
		return -EACCES;
	}

	dprintk("%s uri: %s\n", __func__, login->uri);
	dprintk("%s osdname %s\n", __func__, login->osdname);
	dprintk("%s systemid_hex %s\n", __func__, login->systemid_hex);

	argv[0] = (char *)osd_login_prog;
	argv[1] = "-u";
	argv[2] = login->uri;
	argv[3] = "-o";
	argv[4] = login->osdname;
	argv[5] = "-s";
	argv[6] = login->systemid_hex;
	argv[7] = NULL;

	ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
	/*
	 * Disable the upcall mechanism if we're getting an ENOENT or
	 * EACCES error. The admin can re-enable it on the fly by using
	 * sysfs to set the objlayoutdriver.osd_login_prog module parameter once
	 * the problem has been fixed.
	 */
	if (ret == -ENOENT || ret == -EACCES) {
		printk(KERN_ERR "PNFS-OBJ: %s was not found please set "
			"objlayoutdriver.osd_login_prog kernel parameter!\n",
			osd_login_prog);
		osd_login_prog[0] = '\0';
	}
	dprintk("%s %s return value: %d\n", __func__, osd_login_prog, ret);

	return ret;
}

/* Assume dest is all zeros */
static void __copy_nfsS_and_zero_terminate(struct nfs4_string s,
					   char *dest, int max_len,
					   const char *var_name)
{
	if (!s.len)
		return;

	if (s.len >= max_len) {
		pr_warn_ratelimited(
			"objlayout_autologin: %s: s.len(%d) >= max_len(%d)",
			var_name, s.len, max_len);
		s.len = max_len - 1; /* space for null terminator */
	}

	memcpy(dest, s.data, s.len);
}

/* Assume sysid is all zeros */
static void _sysid_2_hex(struct nfs4_string s,
		  char sysid[OBJLAYOUT_MAX_SYSID_HEX_LEN])
{
	int i;
	char *cur;

	if (!s.len)
		return;

	if (s.len != OSD_SYSTEMID_LEN) {
		pr_warn_ratelimited(
		    "objlayout_autologin: systemid_len(%d) != OSD_SYSTEMID_LEN",
		    s.len);
		if (s.len > OSD_SYSTEMID_LEN)
			s.len = OSD_SYSTEMID_LEN;
	}

	cur = sysid;
	for (i = 0; i < s.len; i++)
		cur = hex_byte_pack(cur, s.data[i]);
}

int objlayout_autologin(struct pnfs_osd_deviceaddr *deviceaddr)
{
	int rc;
	struct __auto_login login;

	if (!deviceaddr->oda_targetaddr.ota_netaddr.r_addr.len)
		return -ENODEV;

	memset(&login, 0, sizeof(login));
	__copy_nfsS_and_zero_terminate(
		deviceaddr->oda_targetaddr.ota_netaddr.r_addr,
		login.uri, sizeof(login.uri), "URI");

	__copy_nfsS_and_zero_terminate(
		deviceaddr->oda_osdname,
		login.osdname, sizeof(login.osdname), "OSDNAME");

	_sysid_2_hex(deviceaddr->oda_systemid, login.systemid_hex);

	rc = __objlayout_upcall(&login);
	if (rc > 0) /* script returns positive values */
		rc = -ENODEV;

	return rc;
}