xref: /linux/fs/nfs/flexfilelayout/flexfilelayout.c (revision 86e00412254a717ffd5d38dc5ec0ee1cce6281b3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Module for pnfs flexfile layout driver.
4  *
5  * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
6  *
7  * Tao Peng <bergwolf@primarydata.com>
8  */
9 
10 #include <linux/nfs_fs.h>
11 #include <linux/nfs_mount.h>
12 #include <linux/nfs_page.h>
13 #include <linux/module.h>
14 #include <linux/file.h>
15 #include <linux/sched/mm.h>
16 
17 #include <linux/sunrpc/metrics.h>
18 
19 #include "flexfilelayout.h"
20 #include "../nfs4session.h"
21 #include "../nfs4idmap.h"
22 #include "../internal.h"
23 #include "../delegation.h"
24 #include "../nfs4trace.h"
25 #include "../iostat.h"
26 #include "../nfs.h"
27 #include "../nfs42.h"
28 
29 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
30 
31 #define FF_LAYOUT_POLL_RETRY_MAX     (15*HZ)
32 #define FF_LAYOUTRETURN_MAXERR 20
33 
34 enum nfs4_ff_op_type {
35 	NFS4_FF_OP_LAYOUTSTATS,
36 	NFS4_FF_OP_LAYOUTRETURN,
37 };
38 
39 static unsigned short io_maxretrans;
40 
41 static const struct pnfs_commit_ops ff_layout_commit_ops;
42 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
43 		struct nfs_pgio_header *hdr);
44 static int
45 ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
46 			       struct nfs42_layoutstat_devinfo *devinfo,
47 			       int dev_limit, enum nfs4_ff_op_type type);
48 static void ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
49 			      const struct nfs42_layoutstat_devinfo *devinfo,
50 			      struct nfs4_ff_layout_mirror *mirror);
51 
52 static struct pnfs_layout_hdr *
53 ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
54 {
55 	struct nfs4_flexfile_layout *ffl;
56 
57 	ffl = kzalloc(sizeof(*ffl), gfp_flags);
58 	if (ffl) {
59 		pnfs_init_ds_commit_info(&ffl->commit_info);
60 		INIT_LIST_HEAD(&ffl->error_list);
61 		INIT_LIST_HEAD(&ffl->mirrors);
62 		ffl->last_report_time = ktime_get();
63 		ffl->commit_info.ops = &ff_layout_commit_ops;
64 		return &ffl->generic_hdr;
65 	} else
66 		return NULL;
67 }
68 
69 static void
70 ff_layout_free_layout_hdr(struct pnfs_layout_hdr *lo)
71 {
72 	struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(lo);
73 	struct nfs4_ff_layout_ds_err *err, *n;
74 
75 	list_for_each_entry_safe(err, n, &ffl->error_list, list) {
76 		list_del(&err->list);
77 		kfree(err);
78 	}
79 	kfree_rcu(ffl, generic_hdr.plh_rcu);
80 }
81 
82 static int decode_pnfs_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
83 {
84 	__be32 *p;
85 
86 	p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
87 	if (unlikely(p == NULL))
88 		return -ENOBUFS;
89 	stateid->type = NFS4_PNFS_DS_STATEID_TYPE;
90 	memcpy(stateid->data, p, NFS4_STATEID_SIZE);
91 	dprintk("%s: stateid id= [%x%x%x%x]\n", __func__,
92 		p[0], p[1], p[2], p[3]);
93 	return 0;
94 }
95 
96 static int decode_deviceid(struct xdr_stream *xdr, struct nfs4_deviceid *devid)
97 {
98 	__be32 *p;
99 
100 	p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE);
101 	if (unlikely(!p))
102 		return -ENOBUFS;
103 	memcpy(devid, p, NFS4_DEVICEID4_SIZE);
104 	nfs4_print_deviceid(devid);
105 	return 0;
106 }
107 
108 static int decode_nfs_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
109 {
110 	__be32 *p;
111 
112 	p = xdr_inline_decode(xdr, 4);
113 	if (unlikely(!p))
114 		return -ENOBUFS;
115 	fh->size = be32_to_cpup(p++);
116 	if (fh->size > NFS_MAXFHSIZE) {
117 		printk(KERN_ERR "NFS flexfiles: Too big fh received %d\n",
118 		       fh->size);
119 		return -EOVERFLOW;
120 	}
121 	/* fh.data */
122 	p = xdr_inline_decode(xdr, fh->size);
123 	if (unlikely(!p))
124 		return -ENOBUFS;
125 	memcpy(&fh->data, p, fh->size);
126 	dprintk("%s: fh len %d\n", __func__, fh->size);
127 
128 	return 0;
129 }
130 
131 /*
132  * Currently only stringified uids and gids are accepted.
133  * I.e., kerberos is not supported to the DSes, so no pricipals.
134  *
135  * That means that one common function will suffice, but when
136  * principals are added, this should be split to accomodate
137  * calls to both nfs_map_name_to_uid() and nfs_map_group_to_gid().
138  */
139 static int
140 decode_name(struct xdr_stream *xdr, u32 *id)
141 {
142 	__be32 *p;
143 	int len;
144 
145 	/* opaque_length(4)*/
146 	p = xdr_inline_decode(xdr, 4);
147 	if (unlikely(!p))
148 		return -ENOBUFS;
149 	len = be32_to_cpup(p++);
150 	if (len < 0)
151 		return -EINVAL;
152 
153 	dprintk("%s: len %u\n", __func__, len);
154 
155 	/* opaque body */
156 	p = xdr_inline_decode(xdr, len);
157 	if (unlikely(!p))
158 		return -ENOBUFS;
159 
160 	if (!nfs_map_string_to_numeric((char *)p, len, id))
161 		return -EINVAL;
162 
163 	return 0;
164 }
165 
166 static struct nfsd_file *
167 ff_local_open_fh(struct pnfs_layout_segment *lseg, u32 ds_idx,
168 		 struct nfs_client *clp, const struct cred *cred,
169 		 struct nfs_fh *fh, fmode_t mode)
170 {
171 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
172 	struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, ds_idx);
173 
174 	return nfs_local_open_fh(clp, cred, fh, &mirror->nfl, mode);
175 #else
176 	return NULL;
177 #endif
178 }
179 
180 static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
181 		const struct nfs4_ff_layout_mirror *m2)
182 {
183 	int i, j;
184 
185 	if (m1->fh_versions_cnt != m2->fh_versions_cnt)
186 		return false;
187 	for (i = 0; i < m1->fh_versions_cnt; i++) {
188 		bool found_fh = false;
189 		for (j = 0; j < m2->fh_versions_cnt; j++) {
190 			if (nfs_compare_fh(&m1->fh_versions[i],
191 					&m2->fh_versions[j]) == 0) {
192 				found_fh = true;
193 				break;
194 			}
195 		}
196 		if (!found_fh)
197 			return false;
198 	}
199 	return true;
200 }
201 
202 static struct nfs4_ff_layout_mirror *
203 ff_layout_add_mirror(struct pnfs_layout_hdr *lo,
204 		struct nfs4_ff_layout_mirror *mirror)
205 {
206 	struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
207 	struct nfs4_ff_layout_mirror *pos;
208 	struct inode *inode = lo->plh_inode;
209 
210 	spin_lock(&inode->i_lock);
211 	list_for_each_entry(pos, &ff_layout->mirrors, mirrors) {
212 		if (memcmp(&mirror->devid, &pos->devid, sizeof(pos->devid)) != 0)
213 			continue;
214 		if (!ff_mirror_match_fh(mirror, pos))
215 			continue;
216 		if (refcount_inc_not_zero(&pos->ref)) {
217 			spin_unlock(&inode->i_lock);
218 			return pos;
219 		}
220 	}
221 	list_add(&mirror->mirrors, &ff_layout->mirrors);
222 	mirror->layout = lo;
223 	spin_unlock(&inode->i_lock);
224 	return mirror;
225 }
226 
227 static void
228 ff_layout_remove_mirror(struct nfs4_ff_layout_mirror *mirror)
229 {
230 	struct inode *inode;
231 	if (mirror->layout == NULL)
232 		return;
233 	inode = mirror->layout->plh_inode;
234 	spin_lock(&inode->i_lock);
235 	list_del(&mirror->mirrors);
236 	spin_unlock(&inode->i_lock);
237 	mirror->layout = NULL;
238 }
239 
240 static struct nfs4_ff_layout_mirror *ff_layout_alloc_mirror(gfp_t gfp_flags)
241 {
242 	struct nfs4_ff_layout_mirror *mirror;
243 
244 	mirror = kzalloc(sizeof(*mirror), gfp_flags);
245 	if (mirror != NULL) {
246 		spin_lock_init(&mirror->lock);
247 		refcount_set(&mirror->ref, 1);
248 		INIT_LIST_HEAD(&mirror->mirrors);
249 		nfs_localio_file_init(&mirror->nfl);
250 	}
251 	return mirror;
252 }
253 
254 static void ff_layout_free_mirror(struct nfs4_ff_layout_mirror *mirror)
255 {
256 	const struct cred *cred;
257 
258 	ff_layout_remove_mirror(mirror);
259 	kfree(mirror->fh_versions);
260 	nfs_close_local_fh(&mirror->nfl);
261 	cred = rcu_access_pointer(mirror->ro_cred);
262 	put_cred(cred);
263 	cred = rcu_access_pointer(mirror->rw_cred);
264 	put_cred(cred);
265 	nfs4_ff_layout_put_deviceid(mirror->mirror_ds);
266 	kfree(mirror);
267 }
268 
269 static void ff_layout_put_mirror(struct nfs4_ff_layout_mirror *mirror)
270 {
271 	if (mirror != NULL && refcount_dec_and_test(&mirror->ref))
272 		ff_layout_free_mirror(mirror);
273 }
274 
275 static void ff_layout_free_mirror_array(struct nfs4_ff_layout_segment *fls)
276 {
277 	u32 i;
278 
279 	for (i = 0; i < fls->mirror_array_cnt; i++)
280 		ff_layout_put_mirror(fls->mirror_array[i]);
281 }
282 
283 static void _ff_layout_free_lseg(struct nfs4_ff_layout_segment *fls)
284 {
285 	if (fls) {
286 		ff_layout_free_mirror_array(fls);
287 		kfree(fls);
288 	}
289 }
290 
291 static bool
292 ff_lseg_match_mirrors(struct pnfs_layout_segment *l1,
293 		struct pnfs_layout_segment *l2)
294 {
295 	const struct nfs4_ff_layout_segment *fl1 = FF_LAYOUT_LSEG(l1);
296 	const struct nfs4_ff_layout_segment *fl2 = FF_LAYOUT_LSEG(l1);
297 	u32 i;
298 
299 	if (fl1->mirror_array_cnt != fl2->mirror_array_cnt)
300 		return false;
301 	for (i = 0; i < fl1->mirror_array_cnt; i++) {
302 		if (fl1->mirror_array[i] != fl2->mirror_array[i])
303 			return false;
304 	}
305 	return true;
306 }
307 
308 static bool
309 ff_lseg_range_is_after(const struct pnfs_layout_range *l1,
310 		const struct pnfs_layout_range *l2)
311 {
312 	u64 end1, end2;
313 
314 	if (l1->iomode != l2->iomode)
315 		return l1->iomode != IOMODE_READ;
316 	end1 = pnfs_calc_offset_end(l1->offset, l1->length);
317 	end2 = pnfs_calc_offset_end(l2->offset, l2->length);
318 	if (end1 < l2->offset)
319 		return false;
320 	if (end2 < l1->offset)
321 		return true;
322 	return l2->offset <= l1->offset;
323 }
324 
325 static bool
326 ff_lseg_merge(struct pnfs_layout_segment *new,
327 		struct pnfs_layout_segment *old)
328 {
329 	u64 new_end, old_end;
330 
331 	if (test_bit(NFS_LSEG_LAYOUTRETURN, &old->pls_flags))
332 		return false;
333 	if (new->pls_range.iomode != old->pls_range.iomode)
334 		return false;
335 	old_end = pnfs_calc_offset_end(old->pls_range.offset,
336 			old->pls_range.length);
337 	if (old_end < new->pls_range.offset)
338 		return false;
339 	new_end = pnfs_calc_offset_end(new->pls_range.offset,
340 			new->pls_range.length);
341 	if (new_end < old->pls_range.offset)
342 		return false;
343 	if (!ff_lseg_match_mirrors(new, old))
344 		return false;
345 
346 	/* Mergeable: copy info from 'old' to 'new' */
347 	if (new_end < old_end)
348 		new_end = old_end;
349 	if (new->pls_range.offset < old->pls_range.offset)
350 		new->pls_range.offset = old->pls_range.offset;
351 	new->pls_range.length = pnfs_calc_offset_length(new->pls_range.offset,
352 			new_end);
353 	if (test_bit(NFS_LSEG_ROC, &old->pls_flags))
354 		set_bit(NFS_LSEG_ROC, &new->pls_flags);
355 	return true;
356 }
357 
358 static void
359 ff_layout_add_lseg(struct pnfs_layout_hdr *lo,
360 		struct pnfs_layout_segment *lseg,
361 		struct list_head *free_me)
362 {
363 	pnfs_generic_layout_insert_lseg(lo, lseg,
364 			ff_lseg_range_is_after,
365 			ff_lseg_merge,
366 			free_me);
367 }
368 
369 static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
370 {
371 	int i, j;
372 
373 	for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
374 		for (j = i + 1; j < fls->mirror_array_cnt; j++)
375 			if (fls->mirror_array[i]->efficiency <
376 			    fls->mirror_array[j]->efficiency)
377 				swap(fls->mirror_array[i],
378 				     fls->mirror_array[j]);
379 	}
380 }
381 
382 static struct pnfs_layout_segment *
383 ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
384 		     struct nfs4_layoutget_res *lgr,
385 		     gfp_t gfp_flags)
386 {
387 	struct pnfs_layout_segment *ret;
388 	struct nfs4_ff_layout_segment *fls = NULL;
389 	struct xdr_stream stream;
390 	struct xdr_buf buf;
391 	struct page *scratch;
392 	u64 stripe_unit;
393 	u32 mirror_array_cnt;
394 	__be32 *p;
395 	int i, rc;
396 
397 	dprintk("--> %s\n", __func__);
398 	scratch = alloc_page(gfp_flags);
399 	if (!scratch)
400 		return ERR_PTR(-ENOMEM);
401 
402 	xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages,
403 			      lgr->layoutp->len);
404 	xdr_set_scratch_page(&stream, scratch);
405 
406 	/* stripe unit and mirror_array_cnt */
407 	rc = -EIO;
408 	p = xdr_inline_decode(&stream, 8 + 4);
409 	if (!p)
410 		goto out_err_free;
411 
412 	p = xdr_decode_hyper(p, &stripe_unit);
413 	mirror_array_cnt = be32_to_cpup(p++);
414 	dprintk("%s: stripe_unit=%llu mirror_array_cnt=%u\n", __func__,
415 		stripe_unit, mirror_array_cnt);
416 
417 	if (mirror_array_cnt > NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT ||
418 	    mirror_array_cnt == 0)
419 		goto out_err_free;
420 
421 	rc = -ENOMEM;
422 	fls = kzalloc(struct_size(fls, mirror_array, mirror_array_cnt),
423 			gfp_flags);
424 	if (!fls)
425 		goto out_err_free;
426 
427 	fls->mirror_array_cnt = mirror_array_cnt;
428 	fls->stripe_unit = stripe_unit;
429 
430 	for (i = 0; i < fls->mirror_array_cnt; i++) {
431 		struct nfs4_ff_layout_mirror *mirror;
432 		struct cred *kcred;
433 		const struct cred __rcu *cred;
434 		kuid_t uid;
435 		kgid_t gid;
436 		u32 ds_count, fh_count, id;
437 		int j;
438 
439 		rc = -EIO;
440 		p = xdr_inline_decode(&stream, 4);
441 		if (!p)
442 			goto out_err_free;
443 		ds_count = be32_to_cpup(p);
444 
445 		/* FIXME: allow for striping? */
446 		if (ds_count != 1)
447 			goto out_err_free;
448 
449 		fls->mirror_array[i] = ff_layout_alloc_mirror(gfp_flags);
450 		if (fls->mirror_array[i] == NULL) {
451 			rc = -ENOMEM;
452 			goto out_err_free;
453 		}
454 
455 		fls->mirror_array[i]->ds_count = ds_count;
456 
457 		/* deviceid */
458 		rc = decode_deviceid(&stream, &fls->mirror_array[i]->devid);
459 		if (rc)
460 			goto out_err_free;
461 
462 		/* efficiency */
463 		rc = -EIO;
464 		p = xdr_inline_decode(&stream, 4);
465 		if (!p)
466 			goto out_err_free;
467 		fls->mirror_array[i]->efficiency = be32_to_cpup(p);
468 
469 		/* stateid */
470 		rc = decode_pnfs_stateid(&stream, &fls->mirror_array[i]->stateid);
471 		if (rc)
472 			goto out_err_free;
473 
474 		/* fh */
475 		rc = -EIO;
476 		p = xdr_inline_decode(&stream, 4);
477 		if (!p)
478 			goto out_err_free;
479 		fh_count = be32_to_cpup(p);
480 
481 		fls->mirror_array[i]->fh_versions =
482 			kcalloc(fh_count, sizeof(struct nfs_fh),
483 				gfp_flags);
484 		if (fls->mirror_array[i]->fh_versions == NULL) {
485 			rc = -ENOMEM;
486 			goto out_err_free;
487 		}
488 
489 		for (j = 0; j < fh_count; j++) {
490 			rc = decode_nfs_fh(&stream,
491 					   &fls->mirror_array[i]->fh_versions[j]);
492 			if (rc)
493 				goto out_err_free;
494 		}
495 
496 		fls->mirror_array[i]->fh_versions_cnt = fh_count;
497 
498 		/* user */
499 		rc = decode_name(&stream, &id);
500 		if (rc)
501 			goto out_err_free;
502 
503 		uid = make_kuid(&init_user_ns, id);
504 
505 		/* group */
506 		rc = decode_name(&stream, &id);
507 		if (rc)
508 			goto out_err_free;
509 
510 		gid = make_kgid(&init_user_ns, id);
511 
512 		if (gfp_flags & __GFP_FS)
513 			kcred = prepare_kernel_cred(&init_task);
514 		else {
515 			unsigned int nofs_flags = memalloc_nofs_save();
516 			kcred = prepare_kernel_cred(&init_task);
517 			memalloc_nofs_restore(nofs_flags);
518 		}
519 		rc = -ENOMEM;
520 		if (!kcred)
521 			goto out_err_free;
522 		kcred->fsuid = uid;
523 		kcred->fsgid = gid;
524 		cred = RCU_INITIALIZER(kcred);
525 
526 		if (lgr->range.iomode == IOMODE_READ)
527 			rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
528 		else
529 			rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
530 
531 		mirror = ff_layout_add_mirror(lh, fls->mirror_array[i]);
532 		if (mirror != fls->mirror_array[i]) {
533 			/* swap cred ptrs so free_mirror will clean up old */
534 			if (lgr->range.iomode == IOMODE_READ) {
535 				cred = xchg(&mirror->ro_cred, cred);
536 				rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
537 			} else {
538 				cred = xchg(&mirror->rw_cred, cred);
539 				rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
540 			}
541 			ff_layout_free_mirror(fls->mirror_array[i]);
542 			fls->mirror_array[i] = mirror;
543 		}
544 
545 		dprintk("%s: iomode %s uid %u gid %u\n", __func__,
546 			lgr->range.iomode == IOMODE_READ ? "READ" : "RW",
547 			from_kuid(&init_user_ns, uid),
548 			from_kgid(&init_user_ns, gid));
549 	}
550 
551 	p = xdr_inline_decode(&stream, 4);
552 	if (!p)
553 		goto out_sort_mirrors;
554 	fls->flags = be32_to_cpup(p);
555 
556 	p = xdr_inline_decode(&stream, 4);
557 	if (!p)
558 		goto out_sort_mirrors;
559 	for (i=0; i < fls->mirror_array_cnt; i++)
560 		fls->mirror_array[i]->report_interval = be32_to_cpup(p);
561 
562 out_sort_mirrors:
563 	ff_layout_sort_mirrors(fls);
564 	ret = &fls->generic_hdr;
565 	dprintk("<-- %s (success)\n", __func__);
566 out_free_page:
567 	__free_page(scratch);
568 	return ret;
569 out_err_free:
570 	_ff_layout_free_lseg(fls);
571 	ret = ERR_PTR(rc);
572 	dprintk("<-- %s (%d)\n", __func__, rc);
573 	goto out_free_page;
574 }
575 
576 static void
577 ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
578 {
579 	struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
580 
581 	dprintk("--> %s\n", __func__);
582 
583 	if (lseg->pls_range.iomode == IOMODE_RW) {
584 		struct nfs4_flexfile_layout *ffl;
585 		struct inode *inode;
586 
587 		ffl = FF_LAYOUT_FROM_HDR(lseg->pls_layout);
588 		inode = ffl->generic_hdr.plh_inode;
589 		spin_lock(&inode->i_lock);
590 		pnfs_generic_ds_cinfo_release_lseg(&ffl->commit_info, lseg);
591 		spin_unlock(&inode->i_lock);
592 	}
593 	_ff_layout_free_lseg(fls);
594 }
595 
596 static void
597 nfs4_ff_start_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
598 {
599 	/* first IO request? */
600 	if (atomic_inc_return(&timer->n_ops) == 1) {
601 		timer->start_time = now;
602 	}
603 }
604 
605 static ktime_t
606 nfs4_ff_end_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
607 {
608 	ktime_t start;
609 
610 	if (atomic_dec_return(&timer->n_ops) < 0)
611 		WARN_ON_ONCE(1);
612 
613 	start = timer->start_time;
614 	timer->start_time = now;
615 	return ktime_sub(now, start);
616 }
617 
618 static bool
619 nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
620 			    struct nfs4_ff_layoutstat *layoutstat,
621 			    ktime_t now)
622 {
623 	s64 report_interval = FF_LAYOUTSTATS_REPORT_INTERVAL;
624 	struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(mirror->layout);
625 
626 	nfs4_ff_start_busy_timer(&layoutstat->busy_timer, now);
627 	if (!mirror->start_time)
628 		mirror->start_time = now;
629 	if (mirror->report_interval != 0)
630 		report_interval = (s64)mirror->report_interval * 1000LL;
631 	else if (layoutstats_timer != 0)
632 		report_interval = (s64)layoutstats_timer * 1000LL;
633 	if (ktime_to_ms(ktime_sub(now, ffl->last_report_time)) >=
634 			report_interval) {
635 		ffl->last_report_time = now;
636 		return true;
637 	}
638 
639 	return false;
640 }
641 
642 static void
643 nfs4_ff_layout_stat_io_update_requested(struct nfs4_ff_layoutstat *layoutstat,
644 		__u64 requested)
645 {
646 	struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
647 
648 	iostat->ops_requested++;
649 	iostat->bytes_requested += requested;
650 }
651 
652 static void
653 nfs4_ff_layout_stat_io_update_completed(struct nfs4_ff_layoutstat *layoutstat,
654 		__u64 requested,
655 		__u64 completed,
656 		ktime_t time_completed,
657 		ktime_t time_started)
658 {
659 	struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
660 	ktime_t completion_time = ktime_sub(time_completed, time_started);
661 	ktime_t timer;
662 
663 	iostat->ops_completed++;
664 	iostat->bytes_completed += completed;
665 	iostat->bytes_not_delivered += requested - completed;
666 
667 	timer = nfs4_ff_end_busy_timer(&layoutstat->busy_timer, time_completed);
668 	iostat->total_busy_time =
669 			ktime_add(iostat->total_busy_time, timer);
670 	iostat->aggregate_completion_time =
671 			ktime_add(iostat->aggregate_completion_time,
672 					completion_time);
673 }
674 
675 static void
676 nfs4_ff_layout_stat_io_start_read(struct inode *inode,
677 		struct nfs4_ff_layout_mirror *mirror,
678 		__u64 requested, ktime_t now)
679 {
680 	bool report;
681 
682 	spin_lock(&mirror->lock);
683 	report = nfs4_ff_layoutstat_start_io(mirror, &mirror->read_stat, now);
684 	nfs4_ff_layout_stat_io_update_requested(&mirror->read_stat, requested);
685 	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
686 	spin_unlock(&mirror->lock);
687 
688 	if (report)
689 		pnfs_report_layoutstat(inode, nfs_io_gfp_mask());
690 }
691 
692 static void
693 nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
694 		struct nfs4_ff_layout_mirror *mirror,
695 		__u64 requested,
696 		__u64 completed)
697 {
698 	spin_lock(&mirror->lock);
699 	nfs4_ff_layout_stat_io_update_completed(&mirror->read_stat,
700 			requested, completed,
701 			ktime_get(), task->tk_start);
702 	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
703 	spin_unlock(&mirror->lock);
704 }
705 
706 static void
707 nfs4_ff_layout_stat_io_start_write(struct inode *inode,
708 		struct nfs4_ff_layout_mirror *mirror,
709 		__u64 requested, ktime_t now)
710 {
711 	bool report;
712 
713 	spin_lock(&mirror->lock);
714 	report = nfs4_ff_layoutstat_start_io(mirror , &mirror->write_stat, now);
715 	nfs4_ff_layout_stat_io_update_requested(&mirror->write_stat, requested);
716 	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
717 	spin_unlock(&mirror->lock);
718 
719 	if (report)
720 		pnfs_report_layoutstat(inode, nfs_io_gfp_mask());
721 }
722 
723 static void
724 nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
725 		struct nfs4_ff_layout_mirror *mirror,
726 		__u64 requested,
727 		__u64 completed,
728 		enum nfs3_stable_how committed)
729 {
730 	if (committed == NFS_UNSTABLE)
731 		requested = completed = 0;
732 
733 	spin_lock(&mirror->lock);
734 	nfs4_ff_layout_stat_io_update_completed(&mirror->write_stat,
735 			requested, completed, ktime_get(), task->tk_start);
736 	set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
737 	spin_unlock(&mirror->lock);
738 }
739 
740 static void
741 ff_layout_mark_ds_unreachable(struct pnfs_layout_segment *lseg, u32 idx)
742 {
743 	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
744 
745 	if (devid)
746 		nfs4_mark_deviceid_unavailable(devid);
747 }
748 
749 static void
750 ff_layout_mark_ds_reachable(struct pnfs_layout_segment *lseg, u32 idx)
751 {
752 	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
753 
754 	if (devid)
755 		nfs4_mark_deviceid_available(devid);
756 }
757 
758 static struct nfs4_pnfs_ds *
759 ff_layout_choose_ds_for_read(struct pnfs_layout_segment *lseg,
760 			     u32 start_idx, u32 *best_idx,
761 			     bool check_device)
762 {
763 	struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
764 	struct nfs4_ff_layout_mirror *mirror;
765 	struct nfs4_pnfs_ds *ds;
766 	u32 idx;
767 
768 	/* mirrors are initially sorted by efficiency */
769 	for (idx = start_idx; idx < fls->mirror_array_cnt; idx++) {
770 		mirror = FF_LAYOUT_COMP(lseg, idx);
771 		ds = nfs4_ff_layout_prepare_ds(lseg, mirror, false);
772 		if (!ds)
773 			continue;
774 
775 		if (check_device &&
776 		    nfs4_test_deviceid_unavailable(&mirror->mirror_ds->id_node))
777 			continue;
778 
779 		*best_idx = idx;
780 		return ds;
781 	}
782 
783 	return NULL;
784 }
785 
786 static struct nfs4_pnfs_ds *
787 ff_layout_choose_any_ds_for_read(struct pnfs_layout_segment *lseg,
788 				 u32 start_idx, u32 *best_idx)
789 {
790 	return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx, false);
791 }
792 
793 static struct nfs4_pnfs_ds *
794 ff_layout_choose_valid_ds_for_read(struct pnfs_layout_segment *lseg,
795 				   u32 start_idx, u32 *best_idx)
796 {
797 	return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx, true);
798 }
799 
800 static struct nfs4_pnfs_ds *
801 ff_layout_choose_best_ds_for_read(struct pnfs_layout_segment *lseg,
802 				  u32 start_idx, u32 *best_idx)
803 {
804 	struct nfs4_pnfs_ds *ds;
805 
806 	ds = ff_layout_choose_valid_ds_for_read(lseg, start_idx, best_idx);
807 	if (ds)
808 		return ds;
809 	return ff_layout_choose_any_ds_for_read(lseg, start_idx, best_idx);
810 }
811 
812 static struct nfs4_pnfs_ds *
813 ff_layout_get_ds_for_read(struct nfs_pageio_descriptor *pgio,
814 			  u32 *best_idx)
815 {
816 	struct pnfs_layout_segment *lseg = pgio->pg_lseg;
817 	struct nfs4_pnfs_ds *ds;
818 
819 	ds = ff_layout_choose_best_ds_for_read(lseg, pgio->pg_mirror_idx,
820 					       best_idx);
821 	if (ds || !pgio->pg_mirror_idx)
822 		return ds;
823 	return ff_layout_choose_best_ds_for_read(lseg, 0, best_idx);
824 }
825 
826 static void
827 ff_layout_pg_get_read(struct nfs_pageio_descriptor *pgio,
828 		      struct nfs_page *req,
829 		      bool strict_iomode)
830 {
831 	pnfs_put_lseg(pgio->pg_lseg);
832 	pgio->pg_lseg =
833 		pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
834 				   req_offset(req), req->wb_bytes, IOMODE_READ,
835 				   strict_iomode, nfs_io_gfp_mask());
836 	if (IS_ERR(pgio->pg_lseg)) {
837 		pgio->pg_error = PTR_ERR(pgio->pg_lseg);
838 		pgio->pg_lseg = NULL;
839 	}
840 }
841 
842 static void
843 ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
844 			struct nfs_page *req)
845 {
846 	struct nfs_pgio_mirror *pgm;
847 	struct nfs4_ff_layout_mirror *mirror;
848 	struct nfs4_pnfs_ds *ds;
849 	u32 ds_idx;
850 
851 retry:
852 	pnfs_generic_pg_check_layout(pgio, req);
853 	/* Use full layout for now */
854 	if (!pgio->pg_lseg) {
855 		ff_layout_pg_get_read(pgio, req, false);
856 		if (!pgio->pg_lseg)
857 			goto out_nolseg;
858 	}
859 	if (ff_layout_avoid_read_on_rw(pgio->pg_lseg)) {
860 		ff_layout_pg_get_read(pgio, req, true);
861 		if (!pgio->pg_lseg)
862 			goto out_nolseg;
863 	}
864 
865 	ds = ff_layout_get_ds_for_read(pgio, &ds_idx);
866 	if (!ds) {
867 		if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
868 			goto out_mds;
869 		pnfs_generic_pg_cleanup(pgio);
870 		/* Sleep for 1 second before retrying */
871 		ssleep(1);
872 		goto retry;
873 	}
874 
875 	mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
876 	pgm = &pgio->pg_mirrors[0];
877 	pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
878 
879 	pgio->pg_mirror_idx = ds_idx;
880 
881 	if (NFS_SERVER(pgio->pg_inode)->flags &
882 			(NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))
883 		pgio->pg_maxretrans = io_maxretrans;
884 	return;
885 out_nolseg:
886 	if (pgio->pg_error < 0)
887 		return;
888 out_mds:
889 	trace_pnfs_mds_fallback_pg_init_read(pgio->pg_inode,
890 			0, NFS4_MAX_UINT64, IOMODE_READ,
891 			NFS_I(pgio->pg_inode)->layout,
892 			pgio->pg_lseg);
893 	pgio->pg_maxretrans = 0;
894 	nfs_pageio_reset_read_mds(pgio);
895 }
896 
897 static void
898 ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
899 			struct nfs_page *req)
900 {
901 	struct nfs4_ff_layout_mirror *mirror;
902 	struct nfs_pgio_mirror *pgm;
903 	struct nfs4_pnfs_ds *ds;
904 	u32 i;
905 
906 retry:
907 	pnfs_generic_pg_check_layout(pgio, req);
908 	if (!pgio->pg_lseg) {
909 		pgio->pg_lseg =
910 			pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
911 					   req_offset(req), req->wb_bytes,
912 					   IOMODE_RW, false, nfs_io_gfp_mask());
913 		if (IS_ERR(pgio->pg_lseg)) {
914 			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
915 			pgio->pg_lseg = NULL;
916 			return;
917 		}
918 	}
919 	/* If no lseg, fall back to write through mds */
920 	if (pgio->pg_lseg == NULL)
921 		goto out_mds;
922 
923 	/* Use a direct mapping of ds_idx to pgio mirror_idx */
924 	if (pgio->pg_mirror_count != FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg))
925 		goto out_eagain;
926 
927 	for (i = 0; i < pgio->pg_mirror_count; i++) {
928 		mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
929 		ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, mirror, true);
930 		if (!ds) {
931 			if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
932 				goto out_mds;
933 			pnfs_generic_pg_cleanup(pgio);
934 			/* Sleep for 1 second before retrying */
935 			ssleep(1);
936 			goto retry;
937 		}
938 		pgm = &pgio->pg_mirrors[i];
939 		pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
940 	}
941 
942 	if (NFS_SERVER(pgio->pg_inode)->flags &
943 			(NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))
944 		pgio->pg_maxretrans = io_maxretrans;
945 	return;
946 out_eagain:
947 	pnfs_generic_pg_cleanup(pgio);
948 	pgio->pg_error = -EAGAIN;
949 	return;
950 out_mds:
951 	trace_pnfs_mds_fallback_pg_init_write(pgio->pg_inode,
952 			0, NFS4_MAX_UINT64, IOMODE_RW,
953 			NFS_I(pgio->pg_inode)->layout,
954 			pgio->pg_lseg);
955 	pgio->pg_maxretrans = 0;
956 	nfs_pageio_reset_write_mds(pgio);
957 	pgio->pg_error = -EAGAIN;
958 }
959 
960 static unsigned int
961 ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
962 				    struct nfs_page *req)
963 {
964 	if (!pgio->pg_lseg) {
965 		pgio->pg_lseg =
966 			pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
967 					   req_offset(req), req->wb_bytes,
968 					   IOMODE_RW, false, nfs_io_gfp_mask());
969 		if (IS_ERR(pgio->pg_lseg)) {
970 			pgio->pg_error = PTR_ERR(pgio->pg_lseg);
971 			pgio->pg_lseg = NULL;
972 			goto out;
973 		}
974 	}
975 	if (pgio->pg_lseg)
976 		return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
977 
978 	trace_pnfs_mds_fallback_pg_get_mirror_count(pgio->pg_inode,
979 			0, NFS4_MAX_UINT64, IOMODE_RW,
980 			NFS_I(pgio->pg_inode)->layout,
981 			pgio->pg_lseg);
982 	/* no lseg means that pnfs is not in use, so no mirroring here */
983 	nfs_pageio_reset_write_mds(pgio);
984 out:
985 	return 1;
986 }
987 
988 static u32
989 ff_layout_pg_set_mirror_write(struct nfs_pageio_descriptor *desc, u32 idx)
990 {
991 	u32 old = desc->pg_mirror_idx;
992 
993 	desc->pg_mirror_idx = idx;
994 	return old;
995 }
996 
997 static struct nfs_pgio_mirror *
998 ff_layout_pg_get_mirror_write(struct nfs_pageio_descriptor *desc, u32 idx)
999 {
1000 	return &desc->pg_mirrors[idx];
1001 }
1002 
1003 static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
1004 	.pg_init = ff_layout_pg_init_read,
1005 	.pg_test = pnfs_generic_pg_test,
1006 	.pg_doio = pnfs_generic_pg_readpages,
1007 	.pg_cleanup = pnfs_generic_pg_cleanup,
1008 };
1009 
1010 static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
1011 	.pg_init = ff_layout_pg_init_write,
1012 	.pg_test = pnfs_generic_pg_test,
1013 	.pg_doio = pnfs_generic_pg_writepages,
1014 	.pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
1015 	.pg_cleanup = pnfs_generic_pg_cleanup,
1016 	.pg_get_mirror = ff_layout_pg_get_mirror_write,
1017 	.pg_set_mirror = ff_layout_pg_set_mirror_write,
1018 };
1019 
1020 static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
1021 {
1022 	struct rpc_task *task = &hdr->task;
1023 
1024 	pnfs_layoutcommit_inode(hdr->inode, false);
1025 
1026 	if (retry_pnfs) {
1027 		dprintk("%s Reset task %5u for i/o through pNFS "
1028 			"(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1029 			hdr->task.tk_pid,
1030 			hdr->inode->i_sb->s_id,
1031 			(unsigned long long)NFS_FILEID(hdr->inode),
1032 			hdr->args.count,
1033 			(unsigned long long)hdr->args.offset);
1034 
1035 		hdr->completion_ops->reschedule_io(hdr);
1036 		return;
1037 	}
1038 
1039 	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1040 		dprintk("%s Reset task %5u for i/o through MDS "
1041 			"(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1042 			hdr->task.tk_pid,
1043 			hdr->inode->i_sb->s_id,
1044 			(unsigned long long)NFS_FILEID(hdr->inode),
1045 			hdr->args.count,
1046 			(unsigned long long)hdr->args.offset);
1047 
1048 		trace_pnfs_mds_fallback_write_done(hdr->inode,
1049 				hdr->args.offset, hdr->args.count,
1050 				IOMODE_RW, NFS_I(hdr->inode)->layout,
1051 				hdr->lseg);
1052 		task->tk_status = pnfs_write_done_resend_to_mds(hdr);
1053 	}
1054 }
1055 
1056 static void ff_layout_resend_pnfs_read(struct nfs_pgio_header *hdr)
1057 {
1058 	u32 idx = hdr->pgio_mirror_idx + 1;
1059 	u32 new_idx = 0;
1060 
1061 	if (ff_layout_choose_any_ds_for_read(hdr->lseg, idx, &new_idx))
1062 		ff_layout_send_layouterror(hdr->lseg);
1063 	else
1064 		pnfs_error_mark_layout_for_return(hdr->inode, hdr->lseg);
1065 	pnfs_read_resend_pnfs(hdr, new_idx);
1066 }
1067 
1068 static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
1069 {
1070 	struct rpc_task *task = &hdr->task;
1071 
1072 	pnfs_layoutcommit_inode(hdr->inode, false);
1073 	pnfs_error_mark_layout_for_return(hdr->inode, hdr->lseg);
1074 
1075 	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1076 		dprintk("%s Reset task %5u for i/o through MDS "
1077 			"(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1078 			hdr->task.tk_pid,
1079 			hdr->inode->i_sb->s_id,
1080 			(unsigned long long)NFS_FILEID(hdr->inode),
1081 			hdr->args.count,
1082 			(unsigned long long)hdr->args.offset);
1083 
1084 		trace_pnfs_mds_fallback_read_done(hdr->inode,
1085 				hdr->args.offset, hdr->args.count,
1086 				IOMODE_READ, NFS_I(hdr->inode)->layout,
1087 				hdr->lseg);
1088 		task->tk_status = pnfs_read_done_resend_to_mds(hdr);
1089 	}
1090 }
1091 
1092 static int ff_layout_async_handle_error_v4(struct rpc_task *task,
1093 					   struct nfs4_state *state,
1094 					   struct nfs_client *clp,
1095 					   struct pnfs_layout_segment *lseg,
1096 					   u32 idx)
1097 {
1098 	struct pnfs_layout_hdr *lo = lseg->pls_layout;
1099 	struct inode *inode = lo->plh_inode;
1100 	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1101 	struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
1102 
1103 	switch (task->tk_status) {
1104 	case -NFS4ERR_BADSESSION:
1105 	case -NFS4ERR_BADSLOT:
1106 	case -NFS4ERR_BAD_HIGH_SLOT:
1107 	case -NFS4ERR_DEADSESSION:
1108 	case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1109 	case -NFS4ERR_SEQ_FALSE_RETRY:
1110 	case -NFS4ERR_SEQ_MISORDERED:
1111 		dprintk("%s ERROR %d, Reset session. Exchangeid "
1112 			"flags 0x%x\n", __func__, task->tk_status,
1113 			clp->cl_exchange_flags);
1114 		nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
1115 		break;
1116 	case -NFS4ERR_DELAY:
1117 	case -NFS4ERR_GRACE:
1118 		rpc_delay(task, FF_LAYOUT_POLL_RETRY_MAX);
1119 		break;
1120 	case -NFS4ERR_RETRY_UNCACHED_REP:
1121 		break;
1122 	/* Invalidate Layout errors */
1123 	case -NFS4ERR_PNFS_NO_LAYOUT:
1124 	case -ESTALE:           /* mapped NFS4ERR_STALE */
1125 	case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
1126 	case -EISDIR:           /* mapped NFS4ERR_ISDIR */
1127 	case -NFS4ERR_FHEXPIRED:
1128 	case -NFS4ERR_WRONG_TYPE:
1129 		dprintk("%s Invalid layout error %d\n", __func__,
1130 			task->tk_status);
1131 		/*
1132 		 * Destroy layout so new i/o will get a new layout.
1133 		 * Layout will not be destroyed until all current lseg
1134 		 * references are put. Mark layout as invalid to resend failed
1135 		 * i/o and all i/o waiting on the slot table to the MDS until
1136 		 * layout is destroyed and a new valid layout is obtained.
1137 		 */
1138 		pnfs_destroy_layout(NFS_I(inode));
1139 		rpc_wake_up(&tbl->slot_tbl_waitq);
1140 		goto reset;
1141 	/* RPC connection errors */
1142 	case -ECONNREFUSED:
1143 	case -EHOSTDOWN:
1144 	case -EHOSTUNREACH:
1145 	case -ENETUNREACH:
1146 	case -EIO:
1147 	case -ETIMEDOUT:
1148 	case -EPIPE:
1149 	case -EPROTO:
1150 	case -ENODEV:
1151 		dprintk("%s DS connection error %d\n", __func__,
1152 			task->tk_status);
1153 		nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1154 				&devid->deviceid);
1155 		rpc_wake_up(&tbl->slot_tbl_waitq);
1156 		fallthrough;
1157 	default:
1158 		if (ff_layout_avoid_mds_available_ds(lseg))
1159 			return -NFS4ERR_RESET_TO_PNFS;
1160 reset:
1161 		dprintk("%s Retry through MDS. Error %d\n", __func__,
1162 			task->tk_status);
1163 		return -NFS4ERR_RESET_TO_MDS;
1164 	}
1165 	task->tk_status = 0;
1166 	return -EAGAIN;
1167 }
1168 
1169 /* Retry all errors through either pNFS or MDS except for -EJUKEBOX */
1170 static int ff_layout_async_handle_error_v3(struct rpc_task *task,
1171 					   struct pnfs_layout_segment *lseg,
1172 					   u32 idx)
1173 {
1174 	struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1175 
1176 	switch (task->tk_status) {
1177 	/* File access problems. Don't mark the device as unavailable */
1178 	case -EACCES:
1179 	case -ESTALE:
1180 	case -EISDIR:
1181 	case -EBADHANDLE:
1182 	case -ELOOP:
1183 	case -ENOSPC:
1184 		break;
1185 	case -EJUKEBOX:
1186 		nfs_inc_stats(lseg->pls_layout->plh_inode, NFSIOS_DELAY);
1187 		goto out_retry;
1188 	default:
1189 		dprintk("%s DS connection error %d\n", __func__,
1190 			task->tk_status);
1191 		nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1192 				&devid->deviceid);
1193 	}
1194 	/* FIXME: Need to prevent infinite looping here. */
1195 	return -NFS4ERR_RESET_TO_PNFS;
1196 out_retry:
1197 	task->tk_status = 0;
1198 	rpc_restart_call_prepare(task);
1199 	rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
1200 	return -EAGAIN;
1201 }
1202 
1203 static int ff_layout_async_handle_error(struct rpc_task *task,
1204 					struct nfs4_state *state,
1205 					struct nfs_client *clp,
1206 					struct pnfs_layout_segment *lseg,
1207 					u32 idx)
1208 {
1209 	int vers = clp->cl_nfs_mod->rpc_vers->number;
1210 
1211 	if (task->tk_status >= 0) {
1212 		ff_layout_mark_ds_reachable(lseg, idx);
1213 		return 0;
1214 	}
1215 
1216 	/* Handle the case of an invalid layout segment */
1217 	if (!pnfs_is_valid_lseg(lseg))
1218 		return -NFS4ERR_RESET_TO_PNFS;
1219 
1220 	switch (vers) {
1221 	case 3:
1222 		return ff_layout_async_handle_error_v3(task, lseg, idx);
1223 	case 4:
1224 		return ff_layout_async_handle_error_v4(task, state, clp,
1225 						       lseg, idx);
1226 	default:
1227 		/* should never happen */
1228 		WARN_ON_ONCE(1);
1229 		return 0;
1230 	}
1231 }
1232 
1233 static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
1234 					u32 idx, u64 offset, u64 length,
1235 					u32 *op_status, int opnum, int error)
1236 {
1237 	struct nfs4_ff_layout_mirror *mirror;
1238 	u32 status = *op_status;
1239 	int err;
1240 
1241 	if (status == 0) {
1242 		switch (error) {
1243 		case -ETIMEDOUT:
1244 		case -EPFNOSUPPORT:
1245 		case -EPROTONOSUPPORT:
1246 		case -EOPNOTSUPP:
1247 		case -EINVAL:
1248 		case -ECONNREFUSED:
1249 		case -ECONNRESET:
1250 		case -EHOSTDOWN:
1251 		case -EHOSTUNREACH:
1252 		case -ENETUNREACH:
1253 		case -EADDRINUSE:
1254 		case -ENOBUFS:
1255 		case -EPIPE:
1256 		case -EPERM:
1257 		case -EPROTO:
1258 		case -ENODEV:
1259 			*op_status = status = NFS4ERR_NXIO;
1260 			break;
1261 		case -EACCES:
1262 			*op_status = status = NFS4ERR_ACCESS;
1263 			break;
1264 		default:
1265 			return;
1266 		}
1267 	}
1268 
1269 	mirror = FF_LAYOUT_COMP(lseg, idx);
1270 	err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
1271 				       mirror, offset, length, status, opnum,
1272 				       nfs_io_gfp_mask());
1273 
1274 	switch (status) {
1275 	case NFS4ERR_DELAY:
1276 	case NFS4ERR_GRACE:
1277 		break;
1278 	case NFS4ERR_NXIO:
1279 		ff_layout_mark_ds_unreachable(lseg, idx);
1280 		/*
1281 		 * Don't return the layout if this is a read and we still
1282 		 * have layouts to try
1283 		 */
1284 		if (opnum == OP_READ)
1285 			break;
1286 		fallthrough;
1287 	default:
1288 		pnfs_error_mark_layout_for_return(lseg->pls_layout->plh_inode,
1289 						  lseg);
1290 	}
1291 
1292 	dprintk("%s: err %d op %d status %u\n", __func__, err, opnum, status);
1293 }
1294 
1295 /* NFS_PROTO call done callback routines */
1296 static int ff_layout_read_done_cb(struct rpc_task *task,
1297 				struct nfs_pgio_header *hdr)
1298 {
1299 	int err;
1300 
1301 	if (task->tk_status < 0) {
1302 		ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1303 					    hdr->args.offset, hdr->args.count,
1304 					    &hdr->res.op_status, OP_READ,
1305 					    task->tk_status);
1306 		trace_ff_layout_read_error(hdr);
1307 	}
1308 
1309 	err = ff_layout_async_handle_error(task, hdr->args.context->state,
1310 					   hdr->ds_clp, hdr->lseg,
1311 					   hdr->pgio_mirror_idx);
1312 
1313 	trace_nfs4_pnfs_read(hdr, err);
1314 	clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1315 	clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1316 	switch (err) {
1317 	case -NFS4ERR_RESET_TO_PNFS:
1318 		set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1319 		return task->tk_status;
1320 	case -NFS4ERR_RESET_TO_MDS:
1321 		set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1322 		return task->tk_status;
1323 	case -EAGAIN:
1324 		goto out_eagain;
1325 	}
1326 
1327 	return 0;
1328 out_eagain:
1329 	rpc_restart_call_prepare(task);
1330 	return -EAGAIN;
1331 }
1332 
1333 static bool
1334 ff_layout_need_layoutcommit(struct pnfs_layout_segment *lseg)
1335 {
1336 	return !(FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_LAYOUTCOMMIT);
1337 }
1338 
1339 /*
1340  * We reference the rpc_cred of the first WRITE that triggers the need for
1341  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
1342  * rfc5661 is not clear about which credential should be used.
1343  *
1344  * Flexlayout client should treat DS replied FILE_SYNC as DATA_SYNC, so
1345  * to follow http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
1346  * we always send layoutcommit after DS writes.
1347  */
1348 static void
1349 ff_layout_set_layoutcommit(struct inode *inode,
1350 		struct pnfs_layout_segment *lseg,
1351 		loff_t end_offset)
1352 {
1353 	if (!ff_layout_need_layoutcommit(lseg))
1354 		return;
1355 
1356 	pnfs_set_layoutcommit(inode, lseg, end_offset);
1357 	dprintk("%s inode %lu pls_end_pos %llu\n", __func__, inode->i_ino,
1358 		(unsigned long long) NFS_I(inode)->layout->plh_lwb);
1359 }
1360 
1361 static void ff_layout_read_record_layoutstats_start(struct rpc_task *task,
1362 		struct nfs_pgio_header *hdr)
1363 {
1364 	if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1365 		return;
1366 	nfs4_ff_layout_stat_io_start_read(hdr->inode,
1367 			FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1368 			hdr->args.count,
1369 			task->tk_start);
1370 }
1371 
1372 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
1373 		struct nfs_pgio_header *hdr)
1374 {
1375 	if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1376 		return;
1377 	nfs4_ff_layout_stat_io_end_read(task,
1378 			FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1379 			hdr->args.count,
1380 			hdr->res.count);
1381 	set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1382 }
1383 
1384 static int ff_layout_read_prepare_common(struct rpc_task *task,
1385 					 struct nfs_pgio_header *hdr)
1386 {
1387 	if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1388 		rpc_exit(task, -EIO);
1389 		return -EIO;
1390 	}
1391 
1392 	if (!pnfs_is_valid_lseg(hdr->lseg)) {
1393 		rpc_exit(task, -EAGAIN);
1394 		return -EAGAIN;
1395 	}
1396 
1397 	ff_layout_read_record_layoutstats_start(task, hdr);
1398 	return 0;
1399 }
1400 
1401 /*
1402  * Call ops for the async read/write cases
1403  * In the case of dense layouts, the offset needs to be reset to its
1404  * original value.
1405  */
1406 static void ff_layout_read_prepare_v3(struct rpc_task *task, void *data)
1407 {
1408 	struct nfs_pgio_header *hdr = data;
1409 
1410 	if (ff_layout_read_prepare_common(task, hdr))
1411 		return;
1412 
1413 	rpc_call_start(task);
1414 }
1415 
1416 static void ff_layout_read_prepare_v4(struct rpc_task *task, void *data)
1417 {
1418 	struct nfs_pgio_header *hdr = data;
1419 
1420 	if (nfs4_setup_sequence(hdr->ds_clp,
1421 				&hdr->args.seq_args,
1422 				&hdr->res.seq_res,
1423 				task))
1424 		return;
1425 
1426 	ff_layout_read_prepare_common(task, hdr);
1427 }
1428 
1429 static void ff_layout_read_call_done(struct rpc_task *task, void *data)
1430 {
1431 	struct nfs_pgio_header *hdr = data;
1432 
1433 	if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1434 	    task->tk_status == 0) {
1435 		nfs4_sequence_done(task, &hdr->res.seq_res);
1436 		return;
1437 	}
1438 
1439 	/* Note this may cause RPC to be resent */
1440 	hdr->mds_ops->rpc_call_done(task, hdr);
1441 }
1442 
1443 static void ff_layout_read_count_stats(struct rpc_task *task, void *data)
1444 {
1445 	struct nfs_pgio_header *hdr = data;
1446 
1447 	ff_layout_read_record_layoutstats_done(task, hdr);
1448 	rpc_count_iostats_metrics(task,
1449 	    &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_READ]);
1450 }
1451 
1452 static void ff_layout_read_release(void *data)
1453 {
1454 	struct nfs_pgio_header *hdr = data;
1455 
1456 	ff_layout_read_record_layoutstats_done(&hdr->task, hdr);
1457 	if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags))
1458 		ff_layout_resend_pnfs_read(hdr);
1459 	else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1460 		ff_layout_reset_read(hdr);
1461 	pnfs_generic_rw_release(data);
1462 }
1463 
1464 
1465 static int ff_layout_write_done_cb(struct rpc_task *task,
1466 				struct nfs_pgio_header *hdr)
1467 {
1468 	loff_t end_offs = 0;
1469 	int err;
1470 
1471 	if (task->tk_status < 0) {
1472 		ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1473 					    hdr->args.offset, hdr->args.count,
1474 					    &hdr->res.op_status, OP_WRITE,
1475 					    task->tk_status);
1476 		trace_ff_layout_write_error(hdr);
1477 	}
1478 
1479 	err = ff_layout_async_handle_error(task, hdr->args.context->state,
1480 					   hdr->ds_clp, hdr->lseg,
1481 					   hdr->pgio_mirror_idx);
1482 
1483 	trace_nfs4_pnfs_write(hdr, err);
1484 	clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1485 	clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1486 	switch (err) {
1487 	case -NFS4ERR_RESET_TO_PNFS:
1488 		set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1489 		return task->tk_status;
1490 	case -NFS4ERR_RESET_TO_MDS:
1491 		set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1492 		return task->tk_status;
1493 	case -EAGAIN:
1494 		return -EAGAIN;
1495 	}
1496 
1497 	if (hdr->res.verf->committed == NFS_FILE_SYNC ||
1498 	    hdr->res.verf->committed == NFS_DATA_SYNC)
1499 		end_offs = hdr->mds_offset + (loff_t)hdr->res.count;
1500 
1501 	/* Note: if the write is unstable, don't set end_offs until commit */
1502 	ff_layout_set_layoutcommit(hdr->inode, hdr->lseg, end_offs);
1503 
1504 	/* zero out fattr since we don't care DS attr at all */
1505 	hdr->fattr.valid = 0;
1506 	if (task->tk_status >= 0)
1507 		nfs_writeback_update_inode(hdr);
1508 
1509 	return 0;
1510 }
1511 
1512 static int ff_layout_commit_done_cb(struct rpc_task *task,
1513 				     struct nfs_commit_data *data)
1514 {
1515 	int err;
1516 
1517 	if (task->tk_status < 0) {
1518 		ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
1519 					    data->args.offset, data->args.count,
1520 					    &data->res.op_status, OP_COMMIT,
1521 					    task->tk_status);
1522 		trace_ff_layout_commit_error(data);
1523 	}
1524 
1525 	err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
1526 					   data->lseg, data->ds_commit_index);
1527 
1528 	trace_nfs4_pnfs_commit_ds(data, err);
1529 	switch (err) {
1530 	case -NFS4ERR_RESET_TO_PNFS:
1531 		pnfs_generic_prepare_to_resend_writes(data);
1532 		return -EAGAIN;
1533 	case -NFS4ERR_RESET_TO_MDS:
1534 		pnfs_generic_prepare_to_resend_writes(data);
1535 		return -EAGAIN;
1536 	case -EAGAIN:
1537 		rpc_restart_call_prepare(task);
1538 		return -EAGAIN;
1539 	}
1540 
1541 	ff_layout_set_layoutcommit(data->inode, data->lseg, data->lwb);
1542 
1543 	return 0;
1544 }
1545 
1546 static void ff_layout_write_record_layoutstats_start(struct rpc_task *task,
1547 		struct nfs_pgio_header *hdr)
1548 {
1549 	if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1550 		return;
1551 	nfs4_ff_layout_stat_io_start_write(hdr->inode,
1552 			FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1553 			hdr->args.count,
1554 			task->tk_start);
1555 }
1556 
1557 static void ff_layout_write_record_layoutstats_done(struct rpc_task *task,
1558 		struct nfs_pgio_header *hdr)
1559 {
1560 	if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1561 		return;
1562 	nfs4_ff_layout_stat_io_end_write(task,
1563 			FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1564 			hdr->args.count, hdr->res.count,
1565 			hdr->res.verf->committed);
1566 	set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1567 }
1568 
1569 static int ff_layout_write_prepare_common(struct rpc_task *task,
1570 					  struct nfs_pgio_header *hdr)
1571 {
1572 	if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1573 		rpc_exit(task, -EIO);
1574 		return -EIO;
1575 	}
1576 
1577 	if (!pnfs_is_valid_lseg(hdr->lseg)) {
1578 		rpc_exit(task, -EAGAIN);
1579 		return -EAGAIN;
1580 	}
1581 
1582 	ff_layout_write_record_layoutstats_start(task, hdr);
1583 	return 0;
1584 }
1585 
1586 static void ff_layout_write_prepare_v3(struct rpc_task *task, void *data)
1587 {
1588 	struct nfs_pgio_header *hdr = data;
1589 
1590 	if (ff_layout_write_prepare_common(task, hdr))
1591 		return;
1592 
1593 	rpc_call_start(task);
1594 }
1595 
1596 static void ff_layout_write_prepare_v4(struct rpc_task *task, void *data)
1597 {
1598 	struct nfs_pgio_header *hdr = data;
1599 
1600 	if (nfs4_setup_sequence(hdr->ds_clp,
1601 				&hdr->args.seq_args,
1602 				&hdr->res.seq_res,
1603 				task))
1604 		return;
1605 
1606 	ff_layout_write_prepare_common(task, hdr);
1607 }
1608 
1609 static void ff_layout_write_call_done(struct rpc_task *task, void *data)
1610 {
1611 	struct nfs_pgio_header *hdr = data;
1612 
1613 	if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1614 	    task->tk_status == 0) {
1615 		nfs4_sequence_done(task, &hdr->res.seq_res);
1616 		return;
1617 	}
1618 
1619 	/* Note this may cause RPC to be resent */
1620 	hdr->mds_ops->rpc_call_done(task, hdr);
1621 }
1622 
1623 static void ff_layout_write_count_stats(struct rpc_task *task, void *data)
1624 {
1625 	struct nfs_pgio_header *hdr = data;
1626 
1627 	ff_layout_write_record_layoutstats_done(task, hdr);
1628 	rpc_count_iostats_metrics(task,
1629 	    &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_WRITE]);
1630 }
1631 
1632 static void ff_layout_write_release(void *data)
1633 {
1634 	struct nfs_pgio_header *hdr = data;
1635 
1636 	ff_layout_write_record_layoutstats_done(&hdr->task, hdr);
1637 	if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags)) {
1638 		ff_layout_send_layouterror(hdr->lseg);
1639 		ff_layout_reset_write(hdr, true);
1640 	} else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1641 		ff_layout_reset_write(hdr, false);
1642 	pnfs_generic_rw_release(data);
1643 }
1644 
1645 static void ff_layout_commit_record_layoutstats_start(struct rpc_task *task,
1646 		struct nfs_commit_data *cdata)
1647 {
1648 	if (test_and_set_bit(NFS_IOHDR_STAT, &cdata->flags))
1649 		return;
1650 	nfs4_ff_layout_stat_io_start_write(cdata->inode,
1651 			FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1652 			0, task->tk_start);
1653 }
1654 
1655 static void ff_layout_commit_record_layoutstats_done(struct rpc_task *task,
1656 		struct nfs_commit_data *cdata)
1657 {
1658 	struct nfs_page *req;
1659 	__u64 count = 0;
1660 
1661 	if (!test_and_clear_bit(NFS_IOHDR_STAT, &cdata->flags))
1662 		return;
1663 
1664 	if (task->tk_status == 0) {
1665 		list_for_each_entry(req, &cdata->pages, wb_list)
1666 			count += req->wb_bytes;
1667 	}
1668 	nfs4_ff_layout_stat_io_end_write(task,
1669 			FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1670 			count, count, NFS_FILE_SYNC);
1671 	set_bit(NFS_LSEG_LAYOUTRETURN, &cdata->lseg->pls_flags);
1672 }
1673 
1674 static int ff_layout_commit_prepare_common(struct rpc_task *task,
1675 					   struct nfs_commit_data *cdata)
1676 {
1677 	if (!pnfs_is_valid_lseg(cdata->lseg)) {
1678 		rpc_exit(task, -EAGAIN);
1679 		return -EAGAIN;
1680 	}
1681 
1682 	ff_layout_commit_record_layoutstats_start(task, cdata);
1683 	return 0;
1684 }
1685 
1686 static void ff_layout_commit_prepare_v3(struct rpc_task *task, void *data)
1687 {
1688 	if (ff_layout_commit_prepare_common(task, data))
1689 		return;
1690 
1691 	rpc_call_start(task);
1692 }
1693 
1694 static void ff_layout_commit_prepare_v4(struct rpc_task *task, void *data)
1695 {
1696 	struct nfs_commit_data *wdata = data;
1697 
1698 	if (nfs4_setup_sequence(wdata->ds_clp,
1699 				&wdata->args.seq_args,
1700 				&wdata->res.seq_res,
1701 				task))
1702 		return;
1703 	ff_layout_commit_prepare_common(task, data);
1704 }
1705 
1706 static void ff_layout_commit_done(struct rpc_task *task, void *data)
1707 {
1708 	pnfs_generic_write_commit_done(task, data);
1709 }
1710 
1711 static void ff_layout_commit_count_stats(struct rpc_task *task, void *data)
1712 {
1713 	struct nfs_commit_data *cdata = data;
1714 
1715 	ff_layout_commit_record_layoutstats_done(task, cdata);
1716 	rpc_count_iostats_metrics(task,
1717 	    &NFS_CLIENT(cdata->inode)->cl_metrics[NFSPROC4_CLNT_COMMIT]);
1718 }
1719 
1720 static void ff_layout_commit_release(void *data)
1721 {
1722 	struct nfs_commit_data *cdata = data;
1723 
1724 	ff_layout_commit_record_layoutstats_done(&cdata->task, cdata);
1725 	pnfs_generic_commit_release(data);
1726 }
1727 
1728 static const struct rpc_call_ops ff_layout_read_call_ops_v3 = {
1729 	.rpc_call_prepare = ff_layout_read_prepare_v3,
1730 	.rpc_call_done = ff_layout_read_call_done,
1731 	.rpc_count_stats = ff_layout_read_count_stats,
1732 	.rpc_release = ff_layout_read_release,
1733 };
1734 
1735 static const struct rpc_call_ops ff_layout_read_call_ops_v4 = {
1736 	.rpc_call_prepare = ff_layout_read_prepare_v4,
1737 	.rpc_call_done = ff_layout_read_call_done,
1738 	.rpc_count_stats = ff_layout_read_count_stats,
1739 	.rpc_release = ff_layout_read_release,
1740 };
1741 
1742 static const struct rpc_call_ops ff_layout_write_call_ops_v3 = {
1743 	.rpc_call_prepare = ff_layout_write_prepare_v3,
1744 	.rpc_call_done = ff_layout_write_call_done,
1745 	.rpc_count_stats = ff_layout_write_count_stats,
1746 	.rpc_release = ff_layout_write_release,
1747 };
1748 
1749 static const struct rpc_call_ops ff_layout_write_call_ops_v4 = {
1750 	.rpc_call_prepare = ff_layout_write_prepare_v4,
1751 	.rpc_call_done = ff_layout_write_call_done,
1752 	.rpc_count_stats = ff_layout_write_count_stats,
1753 	.rpc_release = ff_layout_write_release,
1754 };
1755 
1756 static const struct rpc_call_ops ff_layout_commit_call_ops_v3 = {
1757 	.rpc_call_prepare = ff_layout_commit_prepare_v3,
1758 	.rpc_call_done = ff_layout_commit_done,
1759 	.rpc_count_stats = ff_layout_commit_count_stats,
1760 	.rpc_release = ff_layout_commit_release,
1761 };
1762 
1763 static const struct rpc_call_ops ff_layout_commit_call_ops_v4 = {
1764 	.rpc_call_prepare = ff_layout_commit_prepare_v4,
1765 	.rpc_call_done = ff_layout_commit_done,
1766 	.rpc_count_stats = ff_layout_commit_count_stats,
1767 	.rpc_release = ff_layout_commit_release,
1768 };
1769 
1770 static enum pnfs_try_status
1771 ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
1772 {
1773 	struct pnfs_layout_segment *lseg = hdr->lseg;
1774 	struct nfs4_pnfs_ds *ds;
1775 	struct rpc_clnt *ds_clnt;
1776 	struct nfsd_file *localio;
1777 	struct nfs4_ff_layout_mirror *mirror;
1778 	const struct cred *ds_cred;
1779 	loff_t offset = hdr->args.offset;
1780 	u32 idx = hdr->pgio_mirror_idx;
1781 	int vers;
1782 	struct nfs_fh *fh;
1783 
1784 	dprintk("--> %s ino %lu pgbase %u req %zu@%llu\n",
1785 		__func__, hdr->inode->i_ino,
1786 		hdr->args.pgbase, (size_t)hdr->args.count, offset);
1787 
1788 	mirror = FF_LAYOUT_COMP(lseg, idx);
1789 	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, false);
1790 	if (!ds)
1791 		goto out_failed;
1792 
1793 	ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1794 						   hdr->inode);
1795 	if (IS_ERR(ds_clnt))
1796 		goto out_failed;
1797 
1798 	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
1799 	if (!ds_cred)
1800 		goto out_failed;
1801 
1802 	vers = nfs4_ff_layout_ds_version(mirror);
1803 
1804 	dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
1805 		ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count), vers);
1806 
1807 	hdr->pgio_done_cb = ff_layout_read_done_cb;
1808 	refcount_inc(&ds->ds_clp->cl_count);
1809 	hdr->ds_clp = ds->ds_clp;
1810 	fh = nfs4_ff_layout_select_ds_fh(mirror);
1811 	if (fh)
1812 		hdr->args.fh = fh;
1813 
1814 	nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
1815 
1816 	/*
1817 	 * Note that if we ever decide to split across DSes,
1818 	 * then we may need to handle dense-like offsets.
1819 	 */
1820 	hdr->args.offset = offset;
1821 	hdr->mds_offset = offset;
1822 
1823 	/* Start IO accounting for local read */
1824 	localio = ff_local_open_fh(lseg, idx, ds->ds_clp, ds_cred, fh, FMODE_READ);
1825 	if (localio) {
1826 		hdr->task.tk_start = ktime_get();
1827 		ff_layout_read_record_layoutstats_start(&hdr->task, hdr);
1828 	}
1829 
1830 	/* Perform an asynchronous read to ds */
1831 	nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1832 			  vers == 3 ? &ff_layout_read_call_ops_v3 :
1833 				      &ff_layout_read_call_ops_v4,
1834 			  0, RPC_TASK_SOFTCONN, localio);
1835 	put_cred(ds_cred);
1836 	return PNFS_ATTEMPTED;
1837 
1838 out_failed:
1839 	if (ff_layout_avoid_mds_available_ds(lseg))
1840 		return PNFS_TRY_AGAIN;
1841 	trace_pnfs_mds_fallback_read_pagelist(hdr->inode,
1842 			hdr->args.offset, hdr->args.count,
1843 			IOMODE_READ, NFS_I(hdr->inode)->layout, lseg);
1844 	return PNFS_NOT_ATTEMPTED;
1845 }
1846 
1847 /* Perform async writes. */
1848 static enum pnfs_try_status
1849 ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
1850 {
1851 	struct pnfs_layout_segment *lseg = hdr->lseg;
1852 	struct nfs4_pnfs_ds *ds;
1853 	struct rpc_clnt *ds_clnt;
1854 	struct nfsd_file *localio;
1855 	struct nfs4_ff_layout_mirror *mirror;
1856 	const struct cred *ds_cred;
1857 	loff_t offset = hdr->args.offset;
1858 	int vers;
1859 	struct nfs_fh *fh;
1860 	u32 idx = hdr->pgio_mirror_idx;
1861 
1862 	mirror = FF_LAYOUT_COMP(lseg, idx);
1863 	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
1864 	if (!ds)
1865 		goto out_failed;
1866 
1867 	ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1868 						   hdr->inode);
1869 	if (IS_ERR(ds_clnt))
1870 		goto out_failed;
1871 
1872 	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
1873 	if (!ds_cred)
1874 		goto out_failed;
1875 
1876 	vers = nfs4_ff_layout_ds_version(mirror);
1877 
1878 	dprintk("%s ino %lu sync %d req %zu@%llu DS: %s cl_count %d vers %d\n",
1879 		__func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
1880 		offset, ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count),
1881 		vers);
1882 
1883 	hdr->pgio_done_cb = ff_layout_write_done_cb;
1884 	refcount_inc(&ds->ds_clp->cl_count);
1885 	hdr->ds_clp = ds->ds_clp;
1886 	hdr->ds_commit_idx = idx;
1887 	fh = nfs4_ff_layout_select_ds_fh(mirror);
1888 	if (fh)
1889 		hdr->args.fh = fh;
1890 
1891 	nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
1892 
1893 	/*
1894 	 * Note that if we ever decide to split across DSes,
1895 	 * then we may need to handle dense-like offsets.
1896 	 */
1897 	hdr->args.offset = offset;
1898 
1899 	/* Start IO accounting for local write */
1900 	localio = ff_local_open_fh(lseg, idx, ds->ds_clp, ds_cred, fh,
1901 				   FMODE_READ|FMODE_WRITE);
1902 	if (localio) {
1903 		hdr->task.tk_start = ktime_get();
1904 		ff_layout_write_record_layoutstats_start(&hdr->task, hdr);
1905 	}
1906 
1907 	/* Perform an asynchronous write */
1908 	nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1909 			  vers == 3 ? &ff_layout_write_call_ops_v3 :
1910 				      &ff_layout_write_call_ops_v4,
1911 			  sync, RPC_TASK_SOFTCONN, localio);
1912 	put_cred(ds_cred);
1913 	return PNFS_ATTEMPTED;
1914 
1915 out_failed:
1916 	if (ff_layout_avoid_mds_available_ds(lseg))
1917 		return PNFS_TRY_AGAIN;
1918 	trace_pnfs_mds_fallback_write_pagelist(hdr->inode,
1919 			hdr->args.offset, hdr->args.count,
1920 			IOMODE_RW, NFS_I(hdr->inode)->layout, lseg);
1921 	return PNFS_NOT_ATTEMPTED;
1922 }
1923 
1924 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1925 {
1926 	return i;
1927 }
1928 
1929 static struct nfs_fh *
1930 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1931 {
1932 	struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1933 
1934 	/* FIXME: Assume that there is only one NFS version available
1935 	 * for the DS.
1936 	 */
1937 	return &flseg->mirror_array[i]->fh_versions[0];
1938 }
1939 
1940 static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
1941 {
1942 	struct pnfs_layout_segment *lseg = data->lseg;
1943 	struct nfs4_pnfs_ds *ds;
1944 	struct rpc_clnt *ds_clnt;
1945 	struct nfsd_file *localio;
1946 	struct nfs4_ff_layout_mirror *mirror;
1947 	const struct cred *ds_cred;
1948 	u32 idx;
1949 	int vers, ret;
1950 	struct nfs_fh *fh;
1951 
1952 	if (!lseg || !(pnfs_is_valid_lseg(lseg) ||
1953 	    test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags)))
1954 		goto out_err;
1955 
1956 	idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1957 	mirror = FF_LAYOUT_COMP(lseg, idx);
1958 	ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
1959 	if (!ds)
1960 		goto out_err;
1961 
1962 	ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1963 						   data->inode);
1964 	if (IS_ERR(ds_clnt))
1965 		goto out_err;
1966 
1967 	ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, data->cred);
1968 	if (!ds_cred)
1969 		goto out_err;
1970 
1971 	vers = nfs4_ff_layout_ds_version(mirror);
1972 
1973 	dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
1974 		data->inode->i_ino, how, refcount_read(&ds->ds_clp->cl_count),
1975 		vers);
1976 	data->commit_done_cb = ff_layout_commit_done_cb;
1977 	data->cred = ds_cred;
1978 	refcount_inc(&ds->ds_clp->cl_count);
1979 	data->ds_clp = ds->ds_clp;
1980 	fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1981 	if (fh)
1982 		data->args.fh = fh;
1983 
1984 	/* Start IO accounting for local commit */
1985 	localio = ff_local_open_fh(lseg, idx, ds->ds_clp, ds_cred, fh,
1986 				   FMODE_READ|FMODE_WRITE);
1987 	if (localio) {
1988 		data->task.tk_start = ktime_get();
1989 		ff_layout_commit_record_layoutstats_start(&data->task, data);
1990 	}
1991 
1992 	ret = nfs_initiate_commit(ds_clnt, data, ds->ds_clp->rpc_ops,
1993 				   vers == 3 ? &ff_layout_commit_call_ops_v3 :
1994 					       &ff_layout_commit_call_ops_v4,
1995 				   how, RPC_TASK_SOFTCONN, localio);
1996 	put_cred(ds_cred);
1997 	return ret;
1998 out_err:
1999 	pnfs_generic_prepare_to_resend_writes(data);
2000 	pnfs_generic_commit_release(data);
2001 	return -EAGAIN;
2002 }
2003 
2004 static int
2005 ff_layout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
2006 			   int how, struct nfs_commit_info *cinfo)
2007 {
2008 	return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
2009 					    ff_layout_initiate_commit);
2010 }
2011 
2012 static bool ff_layout_match_rw(const struct rpc_task *task,
2013 			       const struct nfs_pgio_header *hdr,
2014 			       const struct pnfs_layout_segment *lseg)
2015 {
2016 	return hdr->lseg == lseg;
2017 }
2018 
2019 static bool ff_layout_match_commit(const struct rpc_task *task,
2020 				   const struct nfs_commit_data *cdata,
2021 				   const struct pnfs_layout_segment *lseg)
2022 {
2023 	return cdata->lseg == lseg;
2024 }
2025 
2026 static bool ff_layout_match_io(const struct rpc_task *task, const void *data)
2027 {
2028 	const struct rpc_call_ops *ops = task->tk_ops;
2029 
2030 	if (ops == &ff_layout_read_call_ops_v3 ||
2031 	    ops == &ff_layout_read_call_ops_v4 ||
2032 	    ops == &ff_layout_write_call_ops_v3 ||
2033 	    ops == &ff_layout_write_call_ops_v4)
2034 		return ff_layout_match_rw(task, task->tk_calldata, data);
2035 	if (ops == &ff_layout_commit_call_ops_v3 ||
2036 	    ops == &ff_layout_commit_call_ops_v4)
2037 		return ff_layout_match_commit(task, task->tk_calldata, data);
2038 	return false;
2039 }
2040 
2041 static void ff_layout_cancel_io(struct pnfs_layout_segment *lseg)
2042 {
2043 	struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
2044 	struct nfs4_ff_layout_mirror *mirror;
2045 	struct nfs4_ff_layout_ds *mirror_ds;
2046 	struct nfs4_pnfs_ds *ds;
2047 	struct nfs_client *ds_clp;
2048 	struct rpc_clnt *clnt;
2049 	u32 idx;
2050 
2051 	for (idx = 0; idx < flseg->mirror_array_cnt; idx++) {
2052 		mirror = flseg->mirror_array[idx];
2053 		mirror_ds = mirror->mirror_ds;
2054 		if (IS_ERR_OR_NULL(mirror_ds))
2055 			continue;
2056 		ds = mirror->mirror_ds->ds;
2057 		if (!ds)
2058 			continue;
2059 		ds_clp = ds->ds_clp;
2060 		if (!ds_clp)
2061 			continue;
2062 		clnt = ds_clp->cl_rpcclient;
2063 		if (!clnt)
2064 			continue;
2065 		if (!rpc_cancel_tasks(clnt, -EAGAIN, ff_layout_match_io, lseg))
2066 			continue;
2067 		rpc_clnt_disconnect(clnt);
2068 	}
2069 }
2070 
2071 static struct pnfs_ds_commit_info *
2072 ff_layout_get_ds_info(struct inode *inode)
2073 {
2074 	struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
2075 
2076 	if (layout == NULL)
2077 		return NULL;
2078 
2079 	return &FF_LAYOUT_FROM_HDR(layout)->commit_info;
2080 }
2081 
2082 static void
2083 ff_layout_setup_ds_info(struct pnfs_ds_commit_info *fl_cinfo,
2084 		struct pnfs_layout_segment *lseg)
2085 {
2086 	struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
2087 	struct inode *inode = lseg->pls_layout->plh_inode;
2088 	struct pnfs_commit_array *array, *new;
2089 
2090 	new = pnfs_alloc_commit_array(flseg->mirror_array_cnt,
2091 				      nfs_io_gfp_mask());
2092 	if (new) {
2093 		spin_lock(&inode->i_lock);
2094 		array = pnfs_add_commit_array(fl_cinfo, new, lseg);
2095 		spin_unlock(&inode->i_lock);
2096 		if (array != new)
2097 			pnfs_free_commit_array(new);
2098 	}
2099 }
2100 
2101 static void
2102 ff_layout_release_ds_info(struct pnfs_ds_commit_info *fl_cinfo,
2103 		struct inode *inode)
2104 {
2105 	spin_lock(&inode->i_lock);
2106 	pnfs_generic_ds_cinfo_destroy(fl_cinfo);
2107 	spin_unlock(&inode->i_lock);
2108 }
2109 
2110 static void
2111 ff_layout_free_deviceid_node(struct nfs4_deviceid_node *d)
2112 {
2113 	nfs4_ff_layout_free_deviceid(container_of(d, struct nfs4_ff_layout_ds,
2114 						  id_node));
2115 }
2116 
2117 static int ff_layout_encode_ioerr(struct xdr_stream *xdr,
2118 				  const struct nfs4_layoutreturn_args *args,
2119 				  const struct nfs4_flexfile_layoutreturn_args *ff_args)
2120 {
2121 	__be32 *start;
2122 
2123 	start = xdr_reserve_space(xdr, 4);
2124 	if (unlikely(!start))
2125 		return -E2BIG;
2126 
2127 	*start = cpu_to_be32(ff_args->num_errors);
2128 	/* This assume we always return _ALL_ layouts */
2129 	return ff_layout_encode_ds_ioerr(xdr, &ff_args->errors);
2130 }
2131 
2132 static void
2133 ff_layout_encode_ff_iostat_head(struct xdr_stream *xdr,
2134 			    const nfs4_stateid *stateid,
2135 			    const struct nfs42_layoutstat_devinfo *devinfo)
2136 {
2137 	__be32 *p;
2138 
2139 	p = xdr_reserve_space(xdr, 8 + 8);
2140 	p = xdr_encode_hyper(p, devinfo->offset);
2141 	p = xdr_encode_hyper(p, devinfo->length);
2142 	encode_opaque_fixed(xdr, stateid->data, NFS4_STATEID_SIZE);
2143 	p = xdr_reserve_space(xdr, 4*8);
2144 	p = xdr_encode_hyper(p, devinfo->read_count);
2145 	p = xdr_encode_hyper(p, devinfo->read_bytes);
2146 	p = xdr_encode_hyper(p, devinfo->write_count);
2147 	p = xdr_encode_hyper(p, devinfo->write_bytes);
2148 	encode_opaque_fixed(xdr, devinfo->dev_id.data, NFS4_DEVICEID4_SIZE);
2149 }
2150 
2151 static void
2152 ff_layout_encode_ff_iostat(struct xdr_stream *xdr,
2153 			    const nfs4_stateid *stateid,
2154 			    const struct nfs42_layoutstat_devinfo *devinfo)
2155 {
2156 	ff_layout_encode_ff_iostat_head(xdr, stateid, devinfo);
2157 	ff_layout_encode_ff_layoutupdate(xdr, devinfo,
2158 			devinfo->ld_private.data);
2159 }
2160 
2161 /* report nothing for now */
2162 static void ff_layout_encode_iostats_array(struct xdr_stream *xdr,
2163 		const struct nfs4_layoutreturn_args *args,
2164 		struct nfs4_flexfile_layoutreturn_args *ff_args)
2165 {
2166 	__be32 *p;
2167 	int i;
2168 
2169 	p = xdr_reserve_space(xdr, 4);
2170 	*p = cpu_to_be32(ff_args->num_dev);
2171 	for (i = 0; i < ff_args->num_dev; i++)
2172 		ff_layout_encode_ff_iostat(xdr,
2173 				&args->layout->plh_stateid,
2174 				&ff_args->devinfo[i]);
2175 }
2176 
2177 static void
2178 ff_layout_free_iostats_array(struct nfs42_layoutstat_devinfo *devinfo,
2179 		unsigned int num_entries)
2180 {
2181 	unsigned int i;
2182 
2183 	for (i = 0; i < num_entries; i++) {
2184 		if (!devinfo[i].ld_private.ops)
2185 			continue;
2186 		if (!devinfo[i].ld_private.ops->free)
2187 			continue;
2188 		devinfo[i].ld_private.ops->free(&devinfo[i].ld_private);
2189 	}
2190 }
2191 
2192 static struct nfs4_deviceid_node *
2193 ff_layout_alloc_deviceid_node(struct nfs_server *server,
2194 			      struct pnfs_device *pdev, gfp_t gfp_flags)
2195 {
2196 	struct nfs4_ff_layout_ds *dsaddr;
2197 
2198 	dsaddr = nfs4_ff_alloc_deviceid_node(server, pdev, gfp_flags);
2199 	if (!dsaddr)
2200 		return NULL;
2201 	return &dsaddr->id_node;
2202 }
2203 
2204 static void
2205 ff_layout_encode_layoutreturn(struct xdr_stream *xdr,
2206 		const void *voidargs,
2207 		const struct nfs4_xdr_opaque_data *ff_opaque)
2208 {
2209 	const struct nfs4_layoutreturn_args *args = voidargs;
2210 	struct nfs4_flexfile_layoutreturn_args *ff_args = ff_opaque->data;
2211 	struct xdr_buf tmp_buf = {
2212 		.head = {
2213 			[0] = {
2214 				.iov_base = page_address(ff_args->pages[0]),
2215 			},
2216 		},
2217 		.buflen = PAGE_SIZE,
2218 	};
2219 	struct xdr_stream tmp_xdr;
2220 	__be32 *start;
2221 
2222 	dprintk("%s: Begin\n", __func__);
2223 
2224 	xdr_init_encode(&tmp_xdr, &tmp_buf, NULL, NULL);
2225 
2226 	ff_layout_encode_ioerr(&tmp_xdr, args, ff_args);
2227 	ff_layout_encode_iostats_array(&tmp_xdr, args, ff_args);
2228 
2229 	start = xdr_reserve_space(xdr, 4);
2230 	*start = cpu_to_be32(tmp_buf.len);
2231 	xdr_write_pages(xdr, ff_args->pages, 0, tmp_buf.len);
2232 
2233 	dprintk("%s: Return\n", __func__);
2234 }
2235 
2236 static void
2237 ff_layout_free_layoutreturn(struct nfs4_xdr_opaque_data *args)
2238 {
2239 	struct nfs4_flexfile_layoutreturn_args *ff_args;
2240 
2241 	if (!args->data)
2242 		return;
2243 	ff_args = args->data;
2244 	args->data = NULL;
2245 
2246 	ff_layout_free_ds_ioerr(&ff_args->errors);
2247 	ff_layout_free_iostats_array(ff_args->devinfo, ff_args->num_dev);
2248 
2249 	put_page(ff_args->pages[0]);
2250 	kfree(ff_args);
2251 }
2252 
2253 static const struct nfs4_xdr_opaque_ops layoutreturn_ops = {
2254 	.encode = ff_layout_encode_layoutreturn,
2255 	.free = ff_layout_free_layoutreturn,
2256 };
2257 
2258 static int
2259 ff_layout_prepare_layoutreturn(struct nfs4_layoutreturn_args *args)
2260 {
2261 	struct nfs4_flexfile_layoutreturn_args *ff_args;
2262 	struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(args->layout);
2263 
2264 	ff_args = kmalloc(sizeof(*ff_args), nfs_io_gfp_mask());
2265 	if (!ff_args)
2266 		goto out_nomem;
2267 	ff_args->pages[0] = alloc_page(nfs_io_gfp_mask());
2268 	if (!ff_args->pages[0])
2269 		goto out_nomem_free;
2270 
2271 	INIT_LIST_HEAD(&ff_args->errors);
2272 	ff_args->num_errors = ff_layout_fetch_ds_ioerr(args->layout,
2273 			&args->range, &ff_args->errors,
2274 			FF_LAYOUTRETURN_MAXERR);
2275 
2276 	spin_lock(&args->inode->i_lock);
2277 	ff_args->num_dev = ff_layout_mirror_prepare_stats(
2278 		&ff_layout->generic_hdr, &ff_args->devinfo[0],
2279 		ARRAY_SIZE(ff_args->devinfo), NFS4_FF_OP_LAYOUTRETURN);
2280 	spin_unlock(&args->inode->i_lock);
2281 
2282 	args->ld_private->ops = &layoutreturn_ops;
2283 	args->ld_private->data = ff_args;
2284 	return 0;
2285 out_nomem_free:
2286 	kfree(ff_args);
2287 out_nomem:
2288 	return -ENOMEM;
2289 }
2290 
2291 #ifdef CONFIG_NFS_V4_2
2292 void
2293 ff_layout_send_layouterror(struct pnfs_layout_segment *lseg)
2294 {
2295 	struct pnfs_layout_hdr *lo = lseg->pls_layout;
2296 	struct nfs42_layout_error *errors;
2297 	LIST_HEAD(head);
2298 
2299 	if (!nfs_server_capable(lo->plh_inode, NFS_CAP_LAYOUTERROR))
2300 		return;
2301 	ff_layout_fetch_ds_ioerr(lo, &lseg->pls_range, &head, -1);
2302 	if (list_empty(&head))
2303 		return;
2304 
2305 	errors = kmalloc_array(NFS42_LAYOUTERROR_MAX, sizeof(*errors),
2306 			       nfs_io_gfp_mask());
2307 	if (errors != NULL) {
2308 		const struct nfs4_ff_layout_ds_err *pos;
2309 		size_t n = 0;
2310 
2311 		list_for_each_entry(pos, &head, list) {
2312 			errors[n].offset = pos->offset;
2313 			errors[n].length = pos->length;
2314 			nfs4_stateid_copy(&errors[n].stateid, &pos->stateid);
2315 			errors[n].errors[0].dev_id = pos->deviceid;
2316 			errors[n].errors[0].status = pos->status;
2317 			errors[n].errors[0].opnum = pos->opnum;
2318 			n++;
2319 			if (!list_is_last(&pos->list, &head) &&
2320 			    n < NFS42_LAYOUTERROR_MAX)
2321 				continue;
2322 			if (nfs42_proc_layouterror(lseg, errors, n) < 0)
2323 				break;
2324 			n = 0;
2325 		}
2326 		kfree(errors);
2327 	}
2328 	ff_layout_free_ds_ioerr(&head);
2329 }
2330 #else
2331 void
2332 ff_layout_send_layouterror(struct pnfs_layout_segment *lseg)
2333 {
2334 }
2335 #endif
2336 
2337 static int
2338 ff_layout_ntop4(const struct sockaddr *sap, char *buf, const size_t buflen)
2339 {
2340 	const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
2341 
2342 	return snprintf(buf, buflen, "%pI4", &sin->sin_addr);
2343 }
2344 
2345 static size_t
2346 ff_layout_ntop6_noscopeid(const struct sockaddr *sap, char *buf,
2347 			  const int buflen)
2348 {
2349 	const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
2350 	const struct in6_addr *addr = &sin6->sin6_addr;
2351 
2352 	/*
2353 	 * RFC 4291, Section 2.2.2
2354 	 *
2355 	 * Shorthanded ANY address
2356 	 */
2357 	if (ipv6_addr_any(addr))
2358 		return snprintf(buf, buflen, "::");
2359 
2360 	/*
2361 	 * RFC 4291, Section 2.2.2
2362 	 *
2363 	 * Shorthanded loopback address
2364 	 */
2365 	if (ipv6_addr_loopback(addr))
2366 		return snprintf(buf, buflen, "::1");
2367 
2368 	/*
2369 	 * RFC 4291, Section 2.2.3
2370 	 *
2371 	 * Special presentation address format for mapped v4
2372 	 * addresses.
2373 	 */
2374 	if (ipv6_addr_v4mapped(addr))
2375 		return snprintf(buf, buflen, "::ffff:%pI4",
2376 					&addr->s6_addr32[3]);
2377 
2378 	/*
2379 	 * RFC 4291, Section 2.2.1
2380 	 */
2381 	return snprintf(buf, buflen, "%pI6c", addr);
2382 }
2383 
2384 /* Derived from rpc_sockaddr2uaddr */
2385 static void
2386 ff_layout_encode_netaddr(struct xdr_stream *xdr, struct nfs4_pnfs_ds_addr *da)
2387 {
2388 	struct sockaddr *sap = (struct sockaddr *)&da->da_addr;
2389 	char portbuf[RPCBIND_MAXUADDRPLEN];
2390 	char addrbuf[RPCBIND_MAXUADDRLEN];
2391 	unsigned short port;
2392 	int len, netid_len;
2393 	__be32 *p;
2394 
2395 	switch (sap->sa_family) {
2396 	case AF_INET:
2397 		if (ff_layout_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)
2398 			return;
2399 		port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2400 		break;
2401 	case AF_INET6:
2402 		if (ff_layout_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)
2403 			return;
2404 		port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
2405 		break;
2406 	default:
2407 		WARN_ON_ONCE(1);
2408 		return;
2409 	}
2410 
2411 	snprintf(portbuf, sizeof(portbuf), ".%u.%u", port >> 8, port & 0xff);
2412 	len = strlcat(addrbuf, portbuf, sizeof(addrbuf));
2413 
2414 	netid_len = strlen(da->da_netid);
2415 	p = xdr_reserve_space(xdr, 4 + netid_len);
2416 	xdr_encode_opaque(p, da->da_netid, netid_len);
2417 
2418 	p = xdr_reserve_space(xdr, 4 + len);
2419 	xdr_encode_opaque(p, addrbuf, len);
2420 }
2421 
2422 static void
2423 ff_layout_encode_nfstime(struct xdr_stream *xdr,
2424 			 ktime_t t)
2425 {
2426 	struct timespec64 ts;
2427 	__be32 *p;
2428 
2429 	p = xdr_reserve_space(xdr, 12);
2430 	ts = ktime_to_timespec64(t);
2431 	p = xdr_encode_hyper(p, ts.tv_sec);
2432 	*p++ = cpu_to_be32(ts.tv_nsec);
2433 }
2434 
2435 static void
2436 ff_layout_encode_io_latency(struct xdr_stream *xdr,
2437 			    struct nfs4_ff_io_stat *stat)
2438 {
2439 	__be32 *p;
2440 
2441 	p = xdr_reserve_space(xdr, 5 * 8);
2442 	p = xdr_encode_hyper(p, stat->ops_requested);
2443 	p = xdr_encode_hyper(p, stat->bytes_requested);
2444 	p = xdr_encode_hyper(p, stat->ops_completed);
2445 	p = xdr_encode_hyper(p, stat->bytes_completed);
2446 	p = xdr_encode_hyper(p, stat->bytes_not_delivered);
2447 	ff_layout_encode_nfstime(xdr, stat->total_busy_time);
2448 	ff_layout_encode_nfstime(xdr, stat->aggregate_completion_time);
2449 }
2450 
2451 static void
2452 ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
2453 			      const struct nfs42_layoutstat_devinfo *devinfo,
2454 			      struct nfs4_ff_layout_mirror *mirror)
2455 {
2456 	struct nfs4_pnfs_ds_addr *da;
2457 	struct nfs4_pnfs_ds *ds = mirror->mirror_ds->ds;
2458 	struct nfs_fh *fh = &mirror->fh_versions[0];
2459 	__be32 *p;
2460 
2461 	da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
2462 	dprintk("%s: DS %s: encoding address %s\n",
2463 		__func__, ds->ds_remotestr, da->da_remotestr);
2464 	/* netaddr4 */
2465 	ff_layout_encode_netaddr(xdr, da);
2466 	/* nfs_fh4 */
2467 	p = xdr_reserve_space(xdr, 4 + fh->size);
2468 	xdr_encode_opaque(p, fh->data, fh->size);
2469 	/* ff_io_latency4 read */
2470 	spin_lock(&mirror->lock);
2471 	ff_layout_encode_io_latency(xdr, &mirror->read_stat.io_stat);
2472 	/* ff_io_latency4 write */
2473 	ff_layout_encode_io_latency(xdr, &mirror->write_stat.io_stat);
2474 	spin_unlock(&mirror->lock);
2475 	/* nfstime4 */
2476 	ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->start_time));
2477 	/* bool */
2478 	p = xdr_reserve_space(xdr, 4);
2479 	*p = cpu_to_be32(false);
2480 }
2481 
2482 static void
2483 ff_layout_encode_layoutstats(struct xdr_stream *xdr, const void *args,
2484 			     const struct nfs4_xdr_opaque_data *opaque)
2485 {
2486 	struct nfs42_layoutstat_devinfo *devinfo = container_of(opaque,
2487 			struct nfs42_layoutstat_devinfo, ld_private);
2488 	__be32 *start;
2489 
2490 	/* layoutupdate length */
2491 	start = xdr_reserve_space(xdr, 4);
2492 	ff_layout_encode_ff_layoutupdate(xdr, devinfo, opaque->data);
2493 
2494 	*start = cpu_to_be32((xdr->p - start - 1) * 4);
2495 }
2496 
2497 static void
2498 ff_layout_free_layoutstats(struct nfs4_xdr_opaque_data *opaque)
2499 {
2500 	struct nfs4_ff_layout_mirror *mirror = opaque->data;
2501 
2502 	ff_layout_put_mirror(mirror);
2503 }
2504 
2505 static const struct nfs4_xdr_opaque_ops layoutstat_ops = {
2506 	.encode = ff_layout_encode_layoutstats,
2507 	.free	= ff_layout_free_layoutstats,
2508 };
2509 
2510 static int
2511 ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
2512 			       struct nfs42_layoutstat_devinfo *devinfo,
2513 			       int dev_limit, enum nfs4_ff_op_type type)
2514 {
2515 	struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
2516 	struct nfs4_ff_layout_mirror *mirror;
2517 	struct nfs4_deviceid_node *dev;
2518 	int i = 0;
2519 
2520 	list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
2521 		if (i >= dev_limit)
2522 			break;
2523 		if (IS_ERR_OR_NULL(mirror->mirror_ds))
2524 			continue;
2525 		if (!test_and_clear_bit(NFS4_FF_MIRROR_STAT_AVAIL,
2526 					&mirror->flags) &&
2527 		    type != NFS4_FF_OP_LAYOUTRETURN)
2528 			continue;
2529 		/* mirror refcount put in cleanup_layoutstats */
2530 		if (!refcount_inc_not_zero(&mirror->ref))
2531 			continue;
2532 		dev = &mirror->mirror_ds->id_node;
2533 		memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
2534 		devinfo->offset = 0;
2535 		devinfo->length = NFS4_MAX_UINT64;
2536 		spin_lock(&mirror->lock);
2537 		devinfo->read_count = mirror->read_stat.io_stat.ops_completed;
2538 		devinfo->read_bytes = mirror->read_stat.io_stat.bytes_completed;
2539 		devinfo->write_count = mirror->write_stat.io_stat.ops_completed;
2540 		devinfo->write_bytes = mirror->write_stat.io_stat.bytes_completed;
2541 		spin_unlock(&mirror->lock);
2542 		devinfo->layout_type = LAYOUT_FLEX_FILES;
2543 		devinfo->ld_private.ops = &layoutstat_ops;
2544 		devinfo->ld_private.data = mirror;
2545 
2546 		devinfo++;
2547 		i++;
2548 	}
2549 	return i;
2550 }
2551 
2552 static int ff_layout_prepare_layoutstats(struct nfs42_layoutstat_args *args)
2553 {
2554 	struct pnfs_layout_hdr *lo;
2555 	struct nfs4_flexfile_layout *ff_layout;
2556 	const int dev_count = PNFS_LAYOUTSTATS_MAXDEV;
2557 
2558 	/* For now, send at most PNFS_LAYOUTSTATS_MAXDEV statistics */
2559 	args->devinfo = kmalloc_array(dev_count, sizeof(*args->devinfo),
2560 				      nfs_io_gfp_mask());
2561 	if (!args->devinfo)
2562 		return -ENOMEM;
2563 
2564 	spin_lock(&args->inode->i_lock);
2565 	lo = NFS_I(args->inode)->layout;
2566 	if (lo && pnfs_layout_is_valid(lo)) {
2567 		ff_layout = FF_LAYOUT_FROM_HDR(lo);
2568 		args->num_dev = ff_layout_mirror_prepare_stats(
2569 			&ff_layout->generic_hdr, &args->devinfo[0], dev_count,
2570 			NFS4_FF_OP_LAYOUTSTATS);
2571 	} else
2572 		args->num_dev = 0;
2573 	spin_unlock(&args->inode->i_lock);
2574 	if (!args->num_dev) {
2575 		kfree(args->devinfo);
2576 		args->devinfo = NULL;
2577 		return -ENOENT;
2578 	}
2579 
2580 	return 0;
2581 }
2582 
2583 static int
2584 ff_layout_set_layoutdriver(struct nfs_server *server,
2585 		const struct nfs_fh *dummy)
2586 {
2587 #if IS_ENABLED(CONFIG_NFS_V4_2)
2588 	server->caps |= NFS_CAP_LAYOUTSTATS | NFS_CAP_REBOOT_LAYOUTRETURN;
2589 #endif
2590 	return 0;
2591 }
2592 
2593 static const struct pnfs_commit_ops ff_layout_commit_ops = {
2594 	.setup_ds_info		= ff_layout_setup_ds_info,
2595 	.release_ds_info	= ff_layout_release_ds_info,
2596 	.mark_request_commit	= pnfs_layout_mark_request_commit,
2597 	.clear_request_commit	= pnfs_generic_clear_request_commit,
2598 	.scan_commit_lists	= pnfs_generic_scan_commit_lists,
2599 	.recover_commit_reqs	= pnfs_generic_recover_commit_reqs,
2600 	.commit_pagelist	= ff_layout_commit_pagelist,
2601 };
2602 
2603 static struct pnfs_layoutdriver_type flexfilelayout_type = {
2604 	.id			= LAYOUT_FLEX_FILES,
2605 	.name			= "LAYOUT_FLEX_FILES",
2606 	.owner			= THIS_MODULE,
2607 	.flags			= PNFS_LAYOUTGET_ON_OPEN,
2608 	.max_layoutget_response	= 4096, /* 1 page or so... */
2609 	.set_layoutdriver	= ff_layout_set_layoutdriver,
2610 	.alloc_layout_hdr	= ff_layout_alloc_layout_hdr,
2611 	.free_layout_hdr	= ff_layout_free_layout_hdr,
2612 	.alloc_lseg		= ff_layout_alloc_lseg,
2613 	.free_lseg		= ff_layout_free_lseg,
2614 	.add_lseg		= ff_layout_add_lseg,
2615 	.pg_read_ops		= &ff_layout_pg_read_ops,
2616 	.pg_write_ops		= &ff_layout_pg_write_ops,
2617 	.get_ds_info		= ff_layout_get_ds_info,
2618 	.free_deviceid_node	= ff_layout_free_deviceid_node,
2619 	.read_pagelist		= ff_layout_read_pagelist,
2620 	.write_pagelist		= ff_layout_write_pagelist,
2621 	.alloc_deviceid_node    = ff_layout_alloc_deviceid_node,
2622 	.prepare_layoutreturn   = ff_layout_prepare_layoutreturn,
2623 	.sync			= pnfs_nfs_generic_sync,
2624 	.prepare_layoutstats	= ff_layout_prepare_layoutstats,
2625 	.cancel_io		= ff_layout_cancel_io,
2626 };
2627 
2628 static int __init nfs4flexfilelayout_init(void)
2629 {
2630 	printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Registering...\n",
2631 	       __func__);
2632 	return pnfs_register_layoutdriver(&flexfilelayout_type);
2633 }
2634 
2635 static void __exit nfs4flexfilelayout_exit(void)
2636 {
2637 	printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Unregistering...\n",
2638 	       __func__);
2639 	pnfs_unregister_layoutdriver(&flexfilelayout_type);
2640 }
2641 
2642 MODULE_ALIAS("nfs-layouttype4-4");
2643 
2644 MODULE_LICENSE("GPL");
2645 MODULE_DESCRIPTION("The NFSv4 flexfile layout driver");
2646 
2647 module_init(nfs4flexfilelayout_init);
2648 module_exit(nfs4flexfilelayout_exit);
2649 
2650 module_param(io_maxretrans, ushort, 0644);
2651 MODULE_PARM_DESC(io_maxretrans, "The  number of times the NFSv4.1 client "
2652 			"retries an I/O request before returning an error. ");
2653