xref: /openbmc/linux/fs/nfs/pnfs_nfs.c (revision 78700c0a)
1 /*
2  * Common NFS I/O  operations for the pnfs file based
3  * layout drivers.
4  *
5  * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
6  *
7  * Tom Haynes <loghyr@primarydata.com>
8  */
9 
10 #include <linux/nfs_fs.h>
11 #include <linux/nfs_page.h>
12 #include <linux/sunrpc/addr.h>
13 #include <linux/module.h>
14 
15 #include "nfs4session.h"
16 #include "internal.h"
17 #include "pnfs.h"
18 
19 #define NFSDBG_FACILITY		NFSDBG_PNFS
20 
21 void pnfs_generic_rw_release(void *data)
22 {
23 	struct nfs_pgio_header *hdr = data;
24 
25 	nfs_put_client(hdr->ds_clp);
26 	hdr->mds_ops->rpc_release(data);
27 }
28 EXPORT_SYMBOL_GPL(pnfs_generic_rw_release);
29 
30 /* Fake up some data that will cause nfs_commit_release to retry the writes. */
31 void pnfs_generic_prepare_to_resend_writes(struct nfs_commit_data *data)
32 {
33 	struct nfs_page *first = nfs_list_entry(data->pages.next);
34 
35 	data->task.tk_status = 0;
36 	memcpy(&data->verf.verifier, &first->wb_verf,
37 	       sizeof(data->verf.verifier));
38 	data->verf.verifier.data[0]++; /* ensure verifier mismatch */
39 }
40 EXPORT_SYMBOL_GPL(pnfs_generic_prepare_to_resend_writes);
41 
42 void pnfs_generic_write_commit_done(struct rpc_task *task, void *data)
43 {
44 	struct nfs_commit_data *wdata = data;
45 
46 	/* Note this may cause RPC to be resent */
47 	wdata->mds_ops->rpc_call_done(task, data);
48 }
49 EXPORT_SYMBOL_GPL(pnfs_generic_write_commit_done);
50 
51 void pnfs_generic_commit_release(void *calldata)
52 {
53 	struct nfs_commit_data *data = calldata;
54 
55 	data->completion_ops->completion(data);
56 	pnfs_put_lseg(data->lseg);
57 	nfs_put_client(data->ds_clp);
58 	nfs_commitdata_release(data);
59 }
60 EXPORT_SYMBOL_GPL(pnfs_generic_commit_release);
61 
62 /* The generic layer is about to remove the req from the commit list.
63  * If this will make the bucket empty, it will need to put the lseg reference.
64  * Note this must be called holding i_lock
65  */
66 void
67 pnfs_generic_clear_request_commit(struct nfs_page *req,
68 				  struct nfs_commit_info *cinfo)
69 {
70 	struct pnfs_layout_segment *freeme = NULL;
71 
72 	if (!test_and_clear_bit(PG_COMMIT_TO_DS, &req->wb_flags))
73 		goto out;
74 	cinfo->ds->nwritten--;
75 	if (list_is_singular(&req->wb_list)) {
76 		struct pnfs_commit_bucket *bucket;
77 
78 		bucket = list_first_entry(&req->wb_list,
79 					  struct pnfs_commit_bucket,
80 					  written);
81 		freeme = bucket->wlseg;
82 		bucket->wlseg = NULL;
83 	}
84 out:
85 	nfs_request_remove_commit_list(req, cinfo);
86 	pnfs_put_lseg_locked(freeme);
87 }
88 EXPORT_SYMBOL_GPL(pnfs_generic_clear_request_commit);
89 
90 static int
91 pnfs_generic_transfer_commit_list(struct list_head *src, struct list_head *dst,
92 				  struct nfs_commit_info *cinfo, int max)
93 {
94 	struct nfs_page *req, *tmp;
95 	int ret = 0;
96 
97 	list_for_each_entry_safe(req, tmp, src, wb_list) {
98 		if (!nfs_lock_request(req))
99 			continue;
100 		kref_get(&req->wb_kref);
101 		if (cond_resched_lock(&cinfo->inode->i_lock))
102 			list_safe_reset_next(req, tmp, wb_list);
103 		nfs_request_remove_commit_list(req, cinfo);
104 		clear_bit(PG_COMMIT_TO_DS, &req->wb_flags);
105 		nfs_list_add_request(req, dst);
106 		ret++;
107 		if ((ret == max) && !cinfo->dreq)
108 			break;
109 	}
110 	return ret;
111 }
112 
113 static int
114 pnfs_generic_scan_ds_commit_list(struct pnfs_commit_bucket *bucket,
115 				 struct nfs_commit_info *cinfo,
116 				 int max)
117 {
118 	struct list_head *src = &bucket->written;
119 	struct list_head *dst = &bucket->committing;
120 	int ret;
121 
122 	lockdep_assert_held(&cinfo->inode->i_lock);
123 	ret = pnfs_generic_transfer_commit_list(src, dst, cinfo, max);
124 	if (ret) {
125 		cinfo->ds->nwritten -= ret;
126 		cinfo->ds->ncommitting += ret;
127 		if (bucket->clseg == NULL)
128 			bucket->clseg = pnfs_get_lseg(bucket->wlseg);
129 		if (list_empty(src)) {
130 			pnfs_put_lseg_locked(bucket->wlseg);
131 			bucket->wlseg = NULL;
132 		}
133 	}
134 	return ret;
135 }
136 
137 /* Move reqs from written to committing lists, returning count
138  * of number moved.
139  */
140 int pnfs_generic_scan_commit_lists(struct nfs_commit_info *cinfo,
141 				   int max)
142 {
143 	int i, rv = 0, cnt;
144 
145 	lockdep_assert_held(&cinfo->inode->i_lock);
146 	for (i = 0; i < cinfo->ds->nbuckets && max != 0; i++) {
147 		cnt = pnfs_generic_scan_ds_commit_list(&cinfo->ds->buckets[i],
148 						       cinfo, max);
149 		max -= cnt;
150 		rv += cnt;
151 	}
152 	return rv;
153 }
154 EXPORT_SYMBOL_GPL(pnfs_generic_scan_commit_lists);
155 
156 /* Pull everything off the committing lists and dump into @dst.  */
157 void pnfs_generic_recover_commit_reqs(struct list_head *dst,
158 				      struct nfs_commit_info *cinfo)
159 {
160 	struct pnfs_commit_bucket *b;
161 	struct pnfs_layout_segment *freeme;
162 	int i;
163 
164 	lockdep_assert_held(&cinfo->inode->i_lock);
165 restart:
166 	for (i = 0, b = cinfo->ds->buckets; i < cinfo->ds->nbuckets; i++, b++) {
167 		if (pnfs_generic_transfer_commit_list(&b->written, dst,
168 						      cinfo, 0)) {
169 			freeme = b->wlseg;
170 			b->wlseg = NULL;
171 			spin_unlock(&cinfo->inode->i_lock);
172 			pnfs_put_lseg(freeme);
173 			spin_lock(&cinfo->inode->i_lock);
174 			goto restart;
175 		}
176 	}
177 	cinfo->ds->nwritten = 0;
178 }
179 EXPORT_SYMBOL_GPL(pnfs_generic_recover_commit_reqs);
180 
181 static void pnfs_generic_retry_commit(struct nfs_commit_info *cinfo, int idx)
182 {
183 	struct pnfs_ds_commit_info *fl_cinfo = cinfo->ds;
184 	struct pnfs_commit_bucket *bucket;
185 	struct pnfs_layout_segment *freeme;
186 	LIST_HEAD(pages);
187 	int i;
188 
189 	spin_lock(&cinfo->inode->i_lock);
190 	for (i = idx; i < fl_cinfo->nbuckets; i++) {
191 		bucket = &fl_cinfo->buckets[i];
192 		if (list_empty(&bucket->committing))
193 			continue;
194 		freeme = bucket->clseg;
195 		bucket->clseg = NULL;
196 		list_splice_init(&bucket->committing, &pages);
197 		spin_unlock(&cinfo->inode->i_lock);
198 		nfs_retry_commit(&pages, freeme, cinfo, i);
199 		pnfs_put_lseg(freeme);
200 		spin_lock(&cinfo->inode->i_lock);
201 	}
202 	spin_unlock(&cinfo->inode->i_lock);
203 }
204 
205 static unsigned int
206 pnfs_generic_alloc_ds_commits(struct nfs_commit_info *cinfo,
207 			      struct list_head *list)
208 {
209 	struct pnfs_ds_commit_info *fl_cinfo;
210 	struct pnfs_commit_bucket *bucket;
211 	struct nfs_commit_data *data;
212 	int i;
213 	unsigned int nreq = 0;
214 
215 	fl_cinfo = cinfo->ds;
216 	bucket = fl_cinfo->buckets;
217 	for (i = 0; i < fl_cinfo->nbuckets; i++, bucket++) {
218 		if (list_empty(&bucket->committing))
219 			continue;
220 		data = nfs_commitdata_alloc();
221 		if (!data)
222 			break;
223 		data->ds_commit_index = i;
224 		list_add(&data->pages, list);
225 		nreq++;
226 	}
227 
228 	/* Clean up on error */
229 	pnfs_generic_retry_commit(cinfo, i);
230 	return nreq;
231 }
232 
233 static inline
234 void pnfs_fetch_commit_bucket_list(struct list_head *pages,
235 		struct nfs_commit_data *data,
236 		struct nfs_commit_info *cinfo)
237 {
238 	struct pnfs_commit_bucket *bucket;
239 
240 	bucket = &cinfo->ds->buckets[data->ds_commit_index];
241 	spin_lock(&cinfo->inode->i_lock);
242 	list_splice_init(&bucket->committing, pages);
243 	data->lseg = bucket->clseg;
244 	bucket->clseg = NULL;
245 	spin_unlock(&cinfo->inode->i_lock);
246 
247 }
248 
249 /* Helper function for pnfs_generic_commit_pagelist to catch an empty
250  * page list. This can happen when two commits race. */
251 static bool
252 pnfs_generic_commit_cancel_empty_pagelist(struct list_head *pages,
253 					  struct nfs_commit_data *data,
254 					  struct nfs_commit_info *cinfo)
255 {
256 	if (list_empty(pages)) {
257 		if (atomic_dec_and_test(&cinfo->mds->rpcs_out))
258 			wake_up_atomic_t(&cinfo->mds->rpcs_out);
259 		nfs_commitdata_release(data);
260 		return true;
261 	}
262 
263 	return false;
264 }
265 
266 /* This follows nfs_commit_list pretty closely */
267 int
268 pnfs_generic_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
269 			     int how, struct nfs_commit_info *cinfo,
270 			     int (*initiate_commit)(struct nfs_commit_data *data,
271 						    int how))
272 {
273 	struct nfs_commit_data *data, *tmp;
274 	LIST_HEAD(list);
275 	unsigned int nreq = 0;
276 
277 	if (!list_empty(mds_pages)) {
278 		data = nfs_commitdata_alloc();
279 		if (data != NULL) {
280 			data->ds_commit_index = -1;
281 			list_add(&data->pages, &list);
282 			nreq++;
283 		} else {
284 			nfs_retry_commit(mds_pages, NULL, cinfo, 0);
285 			pnfs_generic_retry_commit(cinfo, 0);
286 			return -ENOMEM;
287 		}
288 	}
289 
290 	nreq += pnfs_generic_alloc_ds_commits(cinfo, &list);
291 
292 	if (nreq == 0)
293 		goto out;
294 
295 	atomic_add(nreq, &cinfo->mds->rpcs_out);
296 
297 	list_for_each_entry_safe(data, tmp, &list, pages) {
298 		list_del_init(&data->pages);
299 		if (data->ds_commit_index < 0) {
300 			/* another commit raced with us */
301 			if (pnfs_generic_commit_cancel_empty_pagelist(mds_pages,
302 				data, cinfo))
303 				continue;
304 
305 			nfs_init_commit(data, mds_pages, NULL, cinfo);
306 			nfs_initiate_commit(NFS_CLIENT(inode), data,
307 					    NFS_PROTO(data->inode),
308 					    data->mds_ops, how, 0);
309 		} else {
310 			LIST_HEAD(pages);
311 
312 			pnfs_fetch_commit_bucket_list(&pages, data, cinfo);
313 
314 			/* another commit raced with us */
315 			if (pnfs_generic_commit_cancel_empty_pagelist(&pages,
316 				data, cinfo))
317 				continue;
318 
319 			nfs_init_commit(data, &pages, data->lseg, cinfo);
320 			initiate_commit(data, how);
321 		}
322 	}
323 out:
324 	cinfo->ds->ncommitting = 0;
325 	return PNFS_ATTEMPTED;
326 }
327 EXPORT_SYMBOL_GPL(pnfs_generic_commit_pagelist);
328 
329 /*
330  * Data server cache
331  *
332  * Data servers can be mapped to different device ids.
333  * nfs4_pnfs_ds reference counting
334  *   - set to 1 on allocation
335  *   - incremented when a device id maps a data server already in the cache.
336  *   - decremented when deviceid is removed from the cache.
337  */
338 static DEFINE_SPINLOCK(nfs4_ds_cache_lock);
339 static LIST_HEAD(nfs4_data_server_cache);
340 
341 /* Debug routines */
342 static void
343 print_ds(struct nfs4_pnfs_ds *ds)
344 {
345 	if (ds == NULL) {
346 		printk(KERN_WARNING "%s NULL device\n", __func__);
347 		return;
348 	}
349 	printk(KERN_WARNING "        ds %s\n"
350 		"        ref count %d\n"
351 		"        client %p\n"
352 		"        cl_exchange_flags %x\n",
353 		ds->ds_remotestr,
354 		atomic_read(&ds->ds_count), ds->ds_clp,
355 		ds->ds_clp ? ds->ds_clp->cl_exchange_flags : 0);
356 }
357 
358 static bool
359 same_sockaddr(struct sockaddr *addr1, struct sockaddr *addr2)
360 {
361 	struct sockaddr_in *a, *b;
362 	struct sockaddr_in6 *a6, *b6;
363 
364 	if (addr1->sa_family != addr2->sa_family)
365 		return false;
366 
367 	switch (addr1->sa_family) {
368 	case AF_INET:
369 		a = (struct sockaddr_in *)addr1;
370 		b = (struct sockaddr_in *)addr2;
371 
372 		if (a->sin_addr.s_addr == b->sin_addr.s_addr &&
373 		    a->sin_port == b->sin_port)
374 			return true;
375 		break;
376 
377 	case AF_INET6:
378 		a6 = (struct sockaddr_in6 *)addr1;
379 		b6 = (struct sockaddr_in6 *)addr2;
380 
381 		/* LINKLOCAL addresses must have matching scope_id */
382 		if (ipv6_addr_src_scope(&a6->sin6_addr) ==
383 		    IPV6_ADDR_SCOPE_LINKLOCAL &&
384 		    a6->sin6_scope_id != b6->sin6_scope_id)
385 			return false;
386 
387 		if (ipv6_addr_equal(&a6->sin6_addr, &b6->sin6_addr) &&
388 		    a6->sin6_port == b6->sin6_port)
389 			return true;
390 		break;
391 
392 	default:
393 		dprintk("%s: unhandled address family: %u\n",
394 			__func__, addr1->sa_family);
395 		return false;
396 	}
397 
398 	return false;
399 }
400 
401 /*
402  * Checks if 'dsaddrs1' contains a subset of 'dsaddrs2'. If it does,
403  * declare a match.
404  */
405 static bool
406 _same_data_server_addrs_locked(const struct list_head *dsaddrs1,
407 			       const struct list_head *dsaddrs2)
408 {
409 	struct nfs4_pnfs_ds_addr *da1, *da2;
410 	struct sockaddr *sa1, *sa2;
411 	bool match = false;
412 
413 	list_for_each_entry(da1, dsaddrs1, da_node) {
414 		sa1 = (struct sockaddr *)&da1->da_addr;
415 		match = false;
416 		list_for_each_entry(da2, dsaddrs2, da_node) {
417 			sa2 = (struct sockaddr *)&da2->da_addr;
418 			match = same_sockaddr(sa1, sa2);
419 			if (match)
420 				break;
421 		}
422 		if (!match)
423 			break;
424 	}
425 	return match;
426 }
427 
428 /*
429  * Lookup DS by addresses.  nfs4_ds_cache_lock is held
430  */
431 static struct nfs4_pnfs_ds *
432 _data_server_lookup_locked(const struct list_head *dsaddrs)
433 {
434 	struct nfs4_pnfs_ds *ds;
435 
436 	list_for_each_entry(ds, &nfs4_data_server_cache, ds_node)
437 		if (_same_data_server_addrs_locked(&ds->ds_addrs, dsaddrs))
438 			return ds;
439 	return NULL;
440 }
441 
442 static void destroy_ds(struct nfs4_pnfs_ds *ds)
443 {
444 	struct nfs4_pnfs_ds_addr *da;
445 
446 	dprintk("--> %s\n", __func__);
447 	ifdebug(FACILITY)
448 		print_ds(ds);
449 
450 	nfs_put_client(ds->ds_clp);
451 
452 	while (!list_empty(&ds->ds_addrs)) {
453 		da = list_first_entry(&ds->ds_addrs,
454 				      struct nfs4_pnfs_ds_addr,
455 				      da_node);
456 		list_del_init(&da->da_node);
457 		kfree(da->da_remotestr);
458 		kfree(da);
459 	}
460 
461 	kfree(ds->ds_remotestr);
462 	kfree(ds);
463 }
464 
465 void nfs4_pnfs_ds_put(struct nfs4_pnfs_ds *ds)
466 {
467 	if (atomic_dec_and_lock(&ds->ds_count,
468 				&nfs4_ds_cache_lock)) {
469 		list_del_init(&ds->ds_node);
470 		spin_unlock(&nfs4_ds_cache_lock);
471 		destroy_ds(ds);
472 	}
473 }
474 EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_put);
475 
476 /*
477  * Create a string with a human readable address and port to avoid
478  * complicated setup around many dprinks.
479  */
480 static char *
481 nfs4_pnfs_remotestr(struct list_head *dsaddrs, gfp_t gfp_flags)
482 {
483 	struct nfs4_pnfs_ds_addr *da;
484 	char *remotestr;
485 	size_t len;
486 	char *p;
487 
488 	len = 3;        /* '{', '}' and eol */
489 	list_for_each_entry(da, dsaddrs, da_node) {
490 		len += strlen(da->da_remotestr) + 1;    /* string plus comma */
491 	}
492 
493 	remotestr = kzalloc(len, gfp_flags);
494 	if (!remotestr)
495 		return NULL;
496 
497 	p = remotestr;
498 	*(p++) = '{';
499 	len--;
500 	list_for_each_entry(da, dsaddrs, da_node) {
501 		size_t ll = strlen(da->da_remotestr);
502 
503 		if (ll > len)
504 			goto out_err;
505 
506 		memcpy(p, da->da_remotestr, ll);
507 		p += ll;
508 		len -= ll;
509 
510 		if (len < 1)
511 			goto out_err;
512 		(*p++) = ',';
513 		len--;
514 	}
515 	if (len < 2)
516 		goto out_err;
517 	*(p++) = '}';
518 	*p = '\0';
519 	return remotestr;
520 out_err:
521 	kfree(remotestr);
522 	return NULL;
523 }
524 
525 /*
526  * Given a list of multipath struct nfs4_pnfs_ds_addr, add it to ds cache if
527  * uncached and return cached struct nfs4_pnfs_ds.
528  */
529 struct nfs4_pnfs_ds *
530 nfs4_pnfs_ds_add(struct list_head *dsaddrs, gfp_t gfp_flags)
531 {
532 	struct nfs4_pnfs_ds *tmp_ds, *ds = NULL;
533 	char *remotestr;
534 
535 	if (list_empty(dsaddrs)) {
536 		dprintk("%s: no addresses defined\n", __func__);
537 		goto out;
538 	}
539 
540 	ds = kzalloc(sizeof(*ds), gfp_flags);
541 	if (!ds)
542 		goto out;
543 
544 	/* this is only used for debugging, so it's ok if its NULL */
545 	remotestr = nfs4_pnfs_remotestr(dsaddrs, gfp_flags);
546 
547 	spin_lock(&nfs4_ds_cache_lock);
548 	tmp_ds = _data_server_lookup_locked(dsaddrs);
549 	if (tmp_ds == NULL) {
550 		INIT_LIST_HEAD(&ds->ds_addrs);
551 		list_splice_init(dsaddrs, &ds->ds_addrs);
552 		ds->ds_remotestr = remotestr;
553 		atomic_set(&ds->ds_count, 1);
554 		INIT_LIST_HEAD(&ds->ds_node);
555 		ds->ds_clp = NULL;
556 		list_add(&ds->ds_node, &nfs4_data_server_cache);
557 		dprintk("%s add new data server %s\n", __func__,
558 			ds->ds_remotestr);
559 	} else {
560 		kfree(remotestr);
561 		kfree(ds);
562 		atomic_inc(&tmp_ds->ds_count);
563 		dprintk("%s data server %s found, inc'ed ds_count to %d\n",
564 			__func__, tmp_ds->ds_remotestr,
565 			atomic_read(&tmp_ds->ds_count));
566 		ds = tmp_ds;
567 	}
568 	spin_unlock(&nfs4_ds_cache_lock);
569 out:
570 	return ds;
571 }
572 EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_add);
573 
574 static void nfs4_wait_ds_connect(struct nfs4_pnfs_ds *ds)
575 {
576 	might_sleep();
577 	wait_on_bit(&ds->ds_state, NFS4DS_CONNECTING,
578 			TASK_KILLABLE);
579 }
580 
581 static void nfs4_clear_ds_conn_bit(struct nfs4_pnfs_ds *ds)
582 {
583 	smp_mb__before_atomic();
584 	clear_bit(NFS4DS_CONNECTING, &ds->ds_state);
585 	smp_mb__after_atomic();
586 	wake_up_bit(&ds->ds_state, NFS4DS_CONNECTING);
587 }
588 
589 static struct nfs_client *(*get_v3_ds_connect)(
590 			struct nfs_client *mds_clp,
591 			const struct sockaddr *ds_addr,
592 			int ds_addrlen,
593 			int ds_proto,
594 			unsigned int ds_timeo,
595 			unsigned int ds_retrans,
596 			rpc_authflavor_t au_flavor);
597 
598 static bool load_v3_ds_connect(void)
599 {
600 	if (!get_v3_ds_connect) {
601 		get_v3_ds_connect = symbol_request(nfs3_set_ds_client);
602 		WARN_ON_ONCE(!get_v3_ds_connect);
603 	}
604 
605 	return(get_v3_ds_connect != NULL);
606 }
607 
608 void nfs4_pnfs_v3_ds_connect_unload(void)
609 {
610 	if (get_v3_ds_connect) {
611 		symbol_put(nfs3_set_ds_client);
612 		get_v3_ds_connect = NULL;
613 	}
614 }
615 EXPORT_SYMBOL_GPL(nfs4_pnfs_v3_ds_connect_unload);
616 
617 static int _nfs4_pnfs_v3_ds_connect(struct nfs_server *mds_srv,
618 				 struct nfs4_pnfs_ds *ds,
619 				 unsigned int timeo,
620 				 unsigned int retrans,
621 				 rpc_authflavor_t au_flavor)
622 {
623 	struct nfs_client *clp = ERR_PTR(-EIO);
624 	struct nfs4_pnfs_ds_addr *da;
625 	int status = 0;
626 
627 	dprintk("--> %s DS %s au_flavor %d\n", __func__,
628 		ds->ds_remotestr, au_flavor);
629 
630 	if (!load_v3_ds_connect())
631 		goto out;
632 
633 	list_for_each_entry(da, &ds->ds_addrs, da_node) {
634 		dprintk("%s: DS %s: trying address %s\n",
635 			__func__, ds->ds_remotestr, da->da_remotestr);
636 
637 		if (!IS_ERR(clp)) {
638 			struct xprt_create xprt_args = {
639 				.ident = XPRT_TRANSPORT_TCP,
640 				.net = clp->cl_net,
641 				.dstaddr = (struct sockaddr *)&da->da_addr,
642 				.addrlen = da->da_addrlen,
643 				.servername = clp->cl_hostname,
644 			};
645 			/* Add this address as an alias */
646 			rpc_clnt_add_xprt(clp->cl_rpcclient, &xprt_args,
647 					rpc_clnt_test_and_add_xprt, NULL);
648 		} else
649 			clp = get_v3_ds_connect(mds_srv->nfs_client,
650 					(struct sockaddr *)&da->da_addr,
651 					da->da_addrlen, IPPROTO_TCP,
652 					timeo, retrans, au_flavor);
653 	}
654 
655 	if (IS_ERR(clp)) {
656 		status = PTR_ERR(clp);
657 		goto out;
658 	}
659 
660 	smp_wmb();
661 	ds->ds_clp = clp;
662 	dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
663 out:
664 	return status;
665 }
666 
667 static int _nfs4_pnfs_v4_ds_connect(struct nfs_server *mds_srv,
668 				 struct nfs4_pnfs_ds *ds,
669 				 unsigned int timeo,
670 				 unsigned int retrans,
671 				 u32 minor_version,
672 				 rpc_authflavor_t au_flavor)
673 {
674 	struct nfs_client *clp = ERR_PTR(-EIO);
675 	struct nfs4_pnfs_ds_addr *da;
676 	int status = 0;
677 
678 	dprintk("--> %s DS %s au_flavor %d\n", __func__, ds->ds_remotestr,
679 		au_flavor);
680 
681 	list_for_each_entry(da, &ds->ds_addrs, da_node) {
682 		dprintk("%s: DS %s: trying address %s\n",
683 			__func__, ds->ds_remotestr, da->da_remotestr);
684 
685 		clp = nfs4_set_ds_client(mds_srv->nfs_client,
686 					(struct sockaddr *)&da->da_addr,
687 					da->da_addrlen, IPPROTO_TCP,
688 					timeo, retrans, minor_version,
689 					au_flavor);
690 		if (!IS_ERR(clp))
691 			break;
692 	}
693 
694 	if (IS_ERR(clp)) {
695 		status = PTR_ERR(clp);
696 		goto out;
697 	}
698 
699 	status = nfs4_init_ds_session(clp, mds_srv->nfs_client->cl_lease_time);
700 	if (status)
701 		goto out_put;
702 
703 	smp_wmb();
704 	ds->ds_clp = clp;
705 	dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
706 out:
707 	return status;
708 out_put:
709 	nfs_put_client(clp);
710 	goto out;
711 }
712 
713 /*
714  * Create an rpc connection to the nfs4_pnfs_ds data server.
715  * Currently only supports IPv4 and IPv6 addresses.
716  * If connection fails, make devid unavailable.
717  */
718 void nfs4_pnfs_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds,
719 			  struct nfs4_deviceid_node *devid, unsigned int timeo,
720 			  unsigned int retrans, u32 version,
721 			  u32 minor_version, rpc_authflavor_t au_flavor)
722 {
723 	if (test_and_set_bit(NFS4DS_CONNECTING, &ds->ds_state) == 0) {
724 		int err = 0;
725 
726 		if (version == 3) {
727 			err = _nfs4_pnfs_v3_ds_connect(mds_srv, ds, timeo,
728 						       retrans, au_flavor);
729 		} else if (version == 4) {
730 			err = _nfs4_pnfs_v4_ds_connect(mds_srv, ds, timeo,
731 						       retrans, minor_version,
732 						       au_flavor);
733 		} else {
734 			dprintk("%s: unsupported DS version %d\n", __func__,
735 				version);
736 			err = -EPROTONOSUPPORT;
737 		}
738 
739 		if (err)
740 			nfs4_mark_deviceid_unavailable(devid);
741 		nfs4_clear_ds_conn_bit(ds);
742 	} else {
743 		nfs4_wait_ds_connect(ds);
744 	}
745 }
746 EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_connect);
747 
748 /*
749  * Currently only supports ipv4, ipv6 and one multi-path address.
750  */
751 struct nfs4_pnfs_ds_addr *
752 nfs4_decode_mp_ds_addr(struct net *net, struct xdr_stream *xdr, gfp_t gfp_flags)
753 {
754 	struct nfs4_pnfs_ds_addr *da = NULL;
755 	char *buf, *portstr;
756 	__be16 port;
757 	int nlen, rlen;
758 	int tmp[2];
759 	__be32 *p;
760 	char *netid, *match_netid;
761 	size_t len, match_netid_len;
762 	char *startsep = "";
763 	char *endsep = "";
764 
765 
766 	/* r_netid */
767 	p = xdr_inline_decode(xdr, 4);
768 	if (unlikely(!p))
769 		goto out_err;
770 	nlen = be32_to_cpup(p++);
771 
772 	p = xdr_inline_decode(xdr, nlen);
773 	if (unlikely(!p))
774 		goto out_err;
775 
776 	netid = kmalloc(nlen+1, gfp_flags);
777 	if (unlikely(!netid))
778 		goto out_err;
779 
780 	netid[nlen] = '\0';
781 	memcpy(netid, p, nlen);
782 
783 	/* r_addr: ip/ip6addr with port in dec octets - see RFC 5665 */
784 	p = xdr_inline_decode(xdr, 4);
785 	if (unlikely(!p))
786 		goto out_free_netid;
787 	rlen = be32_to_cpup(p);
788 
789 	p = xdr_inline_decode(xdr, rlen);
790 	if (unlikely(!p))
791 		goto out_free_netid;
792 
793 	/* port is ".ABC.DEF", 8 chars max */
794 	if (rlen > INET6_ADDRSTRLEN + IPV6_SCOPE_ID_LEN + 8) {
795 		dprintk("%s: Invalid address, length %d\n", __func__,
796 			rlen);
797 		goto out_free_netid;
798 	}
799 	buf = kmalloc(rlen + 1, gfp_flags);
800 	if (!buf) {
801 		dprintk("%s: Not enough memory\n", __func__);
802 		goto out_free_netid;
803 	}
804 	buf[rlen] = '\0';
805 	memcpy(buf, p, rlen);
806 
807 	/* replace port '.' with '-' */
808 	portstr = strrchr(buf, '.');
809 	if (!portstr) {
810 		dprintk("%s: Failed finding expected dot in port\n",
811 			__func__);
812 		goto out_free_buf;
813 	}
814 	*portstr = '-';
815 
816 	/* find '.' between address and port */
817 	portstr = strrchr(buf, '.');
818 	if (!portstr) {
819 		dprintk("%s: Failed finding expected dot between address and "
820 			"port\n", __func__);
821 		goto out_free_buf;
822 	}
823 	*portstr = '\0';
824 
825 	da = kzalloc(sizeof(*da), gfp_flags);
826 	if (unlikely(!da))
827 		goto out_free_buf;
828 
829 	INIT_LIST_HEAD(&da->da_node);
830 
831 	if (!rpc_pton(net, buf, portstr-buf, (struct sockaddr *)&da->da_addr,
832 		      sizeof(da->da_addr))) {
833 		dprintk("%s: error parsing address %s\n", __func__, buf);
834 		goto out_free_da;
835 	}
836 
837 	portstr++;
838 	sscanf(portstr, "%d-%d", &tmp[0], &tmp[1]);
839 	port = htons((tmp[0] << 8) | (tmp[1]));
840 
841 	switch (da->da_addr.ss_family) {
842 	case AF_INET:
843 		((struct sockaddr_in *)&da->da_addr)->sin_port = port;
844 		da->da_addrlen = sizeof(struct sockaddr_in);
845 		match_netid = "tcp";
846 		match_netid_len = 3;
847 		break;
848 
849 	case AF_INET6:
850 		((struct sockaddr_in6 *)&da->da_addr)->sin6_port = port;
851 		da->da_addrlen = sizeof(struct sockaddr_in6);
852 		match_netid = "tcp6";
853 		match_netid_len = 4;
854 		startsep = "[";
855 		endsep = "]";
856 		break;
857 
858 	default:
859 		dprintk("%s: unsupported address family: %u\n",
860 			__func__, da->da_addr.ss_family);
861 		goto out_free_da;
862 	}
863 
864 	if (nlen != match_netid_len || strncmp(netid, match_netid, nlen)) {
865 		dprintk("%s: ERROR: r_netid \"%s\" != \"%s\"\n",
866 			__func__, netid, match_netid);
867 		goto out_free_da;
868 	}
869 
870 	/* save human readable address */
871 	len = strlen(startsep) + strlen(buf) + strlen(endsep) + 7;
872 	da->da_remotestr = kzalloc(len, gfp_flags);
873 
874 	/* NULL is ok, only used for dprintk */
875 	if (da->da_remotestr)
876 		snprintf(da->da_remotestr, len, "%s%s%s:%u", startsep,
877 			 buf, endsep, ntohs(port));
878 
879 	dprintk("%s: Parsed DS addr %s\n", __func__, da->da_remotestr);
880 	kfree(buf);
881 	kfree(netid);
882 	return da;
883 
884 out_free_da:
885 	kfree(da);
886 out_free_buf:
887 	dprintk("%s: Error parsing DS addr: %s\n", __func__, buf);
888 	kfree(buf);
889 out_free_netid:
890 	kfree(netid);
891 out_err:
892 	return NULL;
893 }
894 EXPORT_SYMBOL_GPL(nfs4_decode_mp_ds_addr);
895 
896 void
897 pnfs_layout_mark_request_commit(struct nfs_page *req,
898 				struct pnfs_layout_segment *lseg,
899 				struct nfs_commit_info *cinfo,
900 				u32 ds_commit_idx)
901 {
902 	struct list_head *list;
903 	struct pnfs_commit_bucket *buckets;
904 
905 	spin_lock(&cinfo->inode->i_lock);
906 	buckets = cinfo->ds->buckets;
907 	list = &buckets[ds_commit_idx].written;
908 	if (list_empty(list)) {
909 		if (!pnfs_is_valid_lseg(lseg)) {
910 			spin_unlock(&cinfo->inode->i_lock);
911 			cinfo->completion_ops->resched_write(cinfo, req);
912 			return;
913 		}
914 		/* Non-empty buckets hold a reference on the lseg.  That ref
915 		 * is normally transferred to the COMMIT call and released
916 		 * there.  It could also be released if the last req is pulled
917 		 * off due to a rewrite, in which case it will be done in
918 		 * pnfs_common_clear_request_commit
919 		 */
920 		WARN_ON_ONCE(buckets[ds_commit_idx].wlseg != NULL);
921 		buckets[ds_commit_idx].wlseg = pnfs_get_lseg(lseg);
922 	}
923 	set_bit(PG_COMMIT_TO_DS, &req->wb_flags);
924 	cinfo->ds->nwritten++;
925 
926 	nfs_request_add_commit_list_locked(req, list, cinfo);
927 	spin_unlock(&cinfo->inode->i_lock);
928 	nfs_mark_page_unstable(req->wb_page, cinfo);
929 }
930 EXPORT_SYMBOL_GPL(pnfs_layout_mark_request_commit);
931 
932 int
933 pnfs_nfs_generic_sync(struct inode *inode, bool datasync)
934 {
935 	if (datasync)
936 		return 0;
937 	return pnfs_layoutcommit_inode(inode, true);
938 }
939 EXPORT_SYMBOL_GPL(pnfs_nfs_generic_sync);
940 
941