Linux Audio

Check our new training course

Loading...
v4.17
  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
 21void 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}
 28EXPORT_SYMBOL_GPL(pnfs_generic_rw_release);
 29
 30/* Fake up some data that will cause nfs_commit_release to retry the writes. */
 31void 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}
 40EXPORT_SYMBOL_GPL(pnfs_generic_prepare_to_resend_writes);
 41
 42void 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}
 49EXPORT_SYMBOL_GPL(pnfs_generic_write_commit_done);
 50
 51void 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}
 60EXPORT_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 */
 66void
 67pnfs_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	}
 84out:
 85	nfs_request_remove_commit_list(req, cinfo);
 86	pnfs_put_lseg(freeme);
 87}
 88EXPORT_SYMBOL_GPL(pnfs_generic_clear_request_commit);
 89
 90static int
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 91pnfs_generic_scan_ds_commit_list(struct pnfs_commit_bucket *bucket,
 92				 struct nfs_commit_info *cinfo,
 93				 int max)
 94{
 95	struct list_head *src = &bucket->written;
 96	struct list_head *dst = &bucket->committing;
 97	int ret;
 98
 99	lockdep_assert_held(&NFS_I(cinfo->inode)->commit_mutex);
100	ret = nfs_scan_commit_list(src, dst, cinfo, max);
101	if (ret) {
102		cinfo->ds->nwritten -= ret;
103		cinfo->ds->ncommitting += ret;
104		if (bucket->clseg == NULL)
105			bucket->clseg = pnfs_get_lseg(bucket->wlseg);
106		if (list_empty(src)) {
107			pnfs_put_lseg(bucket->wlseg);
108			bucket->wlseg = NULL;
109		}
110	}
111	return ret;
112}
113
114/* Move reqs from written to committing lists, returning count
115 * of number moved.
116 */
117int pnfs_generic_scan_commit_lists(struct nfs_commit_info *cinfo,
118				   int max)
119{
120	int i, rv = 0, cnt;
121
122	lockdep_assert_held(&NFS_I(cinfo->inode)->commit_mutex);
123	for (i = 0; i < cinfo->ds->nbuckets && max != 0; i++) {
124		cnt = pnfs_generic_scan_ds_commit_list(&cinfo->ds->buckets[i],
125						       cinfo, max);
126		max -= cnt;
127		rv += cnt;
128	}
129	return rv;
130}
131EXPORT_SYMBOL_GPL(pnfs_generic_scan_commit_lists);
132
133/* Pull everything off the committing lists and dump into @dst.  */
134void pnfs_generic_recover_commit_reqs(struct list_head *dst,
135				      struct nfs_commit_info *cinfo)
136{
137	struct pnfs_commit_bucket *b;
138	struct pnfs_layout_segment *freeme;
139	int nwritten;
140	int i;
141
142	lockdep_assert_held(&NFS_I(cinfo->inode)->commit_mutex);
143restart:
144	for (i = 0, b = cinfo->ds->buckets; i < cinfo->ds->nbuckets; i++, b++) {
145		nwritten = nfs_scan_commit_list(&b->written, dst, cinfo, 0);
146		if (!nwritten)
147			continue;
148		cinfo->ds->nwritten -= nwritten;
149		if (list_empty(&b->written)) {
150			freeme = b->wlseg;
151			b->wlseg = NULL;
152			spin_unlock(&cinfo->inode->i_lock);
153			pnfs_put_lseg(freeme);
154			spin_lock(&cinfo->inode->i_lock);
155			goto restart;
156		}
157	}
 
158}
159EXPORT_SYMBOL_GPL(pnfs_generic_recover_commit_reqs);
160
161static void pnfs_generic_retry_commit(struct nfs_commit_info *cinfo, int idx)
162{
163	struct pnfs_ds_commit_info *fl_cinfo = cinfo->ds;
164	struct pnfs_commit_bucket *bucket;
165	struct pnfs_layout_segment *freeme;
166	struct list_head *pos;
167	LIST_HEAD(pages);
168	int i;
169
170	spin_lock(&cinfo->inode->i_lock);
171	for (i = idx; i < fl_cinfo->nbuckets; i++) {
172		bucket = &fl_cinfo->buckets[i];
173		if (list_empty(&bucket->committing))
174			continue;
175		freeme = bucket->clseg;
176		bucket->clseg = NULL;
177		list_for_each(pos, &bucket->committing)
178			cinfo->ds->ncommitting--;
179		list_splice_init(&bucket->committing, &pages);
180		spin_unlock(&cinfo->inode->i_lock);
181		nfs_retry_commit(&pages, freeme, cinfo, i);
182		pnfs_put_lseg(freeme);
183		spin_lock(&cinfo->inode->i_lock);
184	}
185	spin_unlock(&cinfo->inode->i_lock);
186}
187
188static unsigned int
189pnfs_generic_alloc_ds_commits(struct nfs_commit_info *cinfo,
190			      struct list_head *list)
191{
192	struct pnfs_ds_commit_info *fl_cinfo;
193	struct pnfs_commit_bucket *bucket;
194	struct nfs_commit_data *data;
195	int i;
196	unsigned int nreq = 0;
197
198	fl_cinfo = cinfo->ds;
199	bucket = fl_cinfo->buckets;
200	for (i = 0; i < fl_cinfo->nbuckets; i++, bucket++) {
201		if (list_empty(&bucket->committing))
202			continue;
203		data = nfs_commitdata_alloc(false);
204		if (!data)
205			break;
206		data->ds_commit_index = i;
207		list_add(&data->pages, list);
208		nreq++;
209	}
210
211	/* Clean up on error */
212	pnfs_generic_retry_commit(cinfo, i);
213	return nreq;
214}
215
216static inline
217void pnfs_fetch_commit_bucket_list(struct list_head *pages,
218		struct nfs_commit_data *data,
219		struct nfs_commit_info *cinfo)
220{
221	struct pnfs_commit_bucket *bucket;
222	struct list_head *pos;
223
224	bucket = &cinfo->ds->buckets[data->ds_commit_index];
225	spin_lock(&cinfo->inode->i_lock);
226	list_for_each(pos, &bucket->committing)
227		cinfo->ds->ncommitting--;
228	list_splice_init(&bucket->committing, pages);
229	data->lseg = bucket->clseg;
230	bucket->clseg = NULL;
231	spin_unlock(&cinfo->inode->i_lock);
232
233}
234
235/* Helper function for pnfs_generic_commit_pagelist to catch an empty
236 * page list. This can happen when two commits race.
237 *
238 * This must be called instead of nfs_init_commit - call one or the other, but
239 * not both!
240 */
241static bool
242pnfs_generic_commit_cancel_empty_pagelist(struct list_head *pages,
243					  struct nfs_commit_data *data,
244					  struct nfs_commit_info *cinfo)
245{
246	if (list_empty(pages)) {
247		if (atomic_dec_and_test(&cinfo->mds->rpcs_out))
248			wake_up_var(&cinfo->mds->rpcs_out);
249		/* don't call nfs_commitdata_release - it tries to put
250		 * the open_context which is not acquired until nfs_init_commit
251		 * which has not been called on @data */
252		WARN_ON_ONCE(data->context);
253		nfs_commit_free(data);
254		return true;
255	}
256
257	return false;
258}
259
260/* This follows nfs_commit_list pretty closely */
261int
262pnfs_generic_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
263			     int how, struct nfs_commit_info *cinfo,
264			     int (*initiate_commit)(struct nfs_commit_data *data,
265						    int how))
266{
267	struct nfs_commit_data *data, *tmp;
268	LIST_HEAD(list);
269	unsigned int nreq = 0;
270
271	if (!list_empty(mds_pages)) {
272		data = nfs_commitdata_alloc(true);
273		data->ds_commit_index = -1;
274		list_add(&data->pages, &list);
275		nreq++;
 
 
 
 
 
 
276	}
277
278	nreq += pnfs_generic_alloc_ds_commits(cinfo, &list);
279
280	if (nreq == 0)
281		goto out;
282
283	atomic_add(nreq, &cinfo->mds->rpcs_out);
284
285	list_for_each_entry_safe(data, tmp, &list, pages) {
286		list_del_init(&data->pages);
287		if (data->ds_commit_index < 0) {
288			/* another commit raced with us */
289			if (pnfs_generic_commit_cancel_empty_pagelist(mds_pages,
290				data, cinfo))
291				continue;
292
293			nfs_init_commit(data, mds_pages, NULL, cinfo);
294			nfs_initiate_commit(NFS_CLIENT(inode), data,
295					    NFS_PROTO(data->inode),
296					    data->mds_ops, how, 0);
297		} else {
298			LIST_HEAD(pages);
299
300			pnfs_fetch_commit_bucket_list(&pages, data, cinfo);
301
302			/* another commit raced with us */
303			if (pnfs_generic_commit_cancel_empty_pagelist(&pages,
304				data, cinfo))
305				continue;
306
307			nfs_init_commit(data, &pages, data->lseg, cinfo);
308			initiate_commit(data, how);
309		}
310	}
311out:
 
312	return PNFS_ATTEMPTED;
313}
314EXPORT_SYMBOL_GPL(pnfs_generic_commit_pagelist);
315
316/*
317 * Data server cache
318 *
319 * Data servers can be mapped to different device ids.
320 * nfs4_pnfs_ds reference counting
321 *   - set to 1 on allocation
322 *   - incremented when a device id maps a data server already in the cache.
323 *   - decremented when deviceid is removed from the cache.
324 */
325static DEFINE_SPINLOCK(nfs4_ds_cache_lock);
326static LIST_HEAD(nfs4_data_server_cache);
327
328/* Debug routines */
329static void
330print_ds(struct nfs4_pnfs_ds *ds)
331{
332	if (ds == NULL) {
333		printk(KERN_WARNING "%s NULL device\n", __func__);
334		return;
335	}
336	printk(KERN_WARNING "        ds %s\n"
337		"        ref count %d\n"
338		"        client %p\n"
339		"        cl_exchange_flags %x\n",
340		ds->ds_remotestr,
341		refcount_read(&ds->ds_count), ds->ds_clp,
342		ds->ds_clp ? ds->ds_clp->cl_exchange_flags : 0);
343}
344
345static bool
346same_sockaddr(struct sockaddr *addr1, struct sockaddr *addr2)
347{
348	struct sockaddr_in *a, *b;
349	struct sockaddr_in6 *a6, *b6;
350
351	if (addr1->sa_family != addr2->sa_family)
352		return false;
353
354	switch (addr1->sa_family) {
355	case AF_INET:
356		a = (struct sockaddr_in *)addr1;
357		b = (struct sockaddr_in *)addr2;
358
359		if (a->sin_addr.s_addr == b->sin_addr.s_addr &&
360		    a->sin_port == b->sin_port)
361			return true;
362		break;
363
364	case AF_INET6:
365		a6 = (struct sockaddr_in6 *)addr1;
366		b6 = (struct sockaddr_in6 *)addr2;
367
368		/* LINKLOCAL addresses must have matching scope_id */
369		if (ipv6_addr_src_scope(&a6->sin6_addr) ==
370		    IPV6_ADDR_SCOPE_LINKLOCAL &&
371		    a6->sin6_scope_id != b6->sin6_scope_id)
372			return false;
373
374		if (ipv6_addr_equal(&a6->sin6_addr, &b6->sin6_addr) &&
375		    a6->sin6_port == b6->sin6_port)
376			return true;
377		break;
378
379	default:
380		dprintk("%s: unhandled address family: %u\n",
381			__func__, addr1->sa_family);
382		return false;
383	}
384
385	return false;
386}
387
388/*
389 * Checks if 'dsaddrs1' contains a subset of 'dsaddrs2'. If it does,
390 * declare a match.
391 */
392static bool
393_same_data_server_addrs_locked(const struct list_head *dsaddrs1,
394			       const struct list_head *dsaddrs2)
395{
396	struct nfs4_pnfs_ds_addr *da1, *da2;
397	struct sockaddr *sa1, *sa2;
398	bool match = false;
399
400	list_for_each_entry(da1, dsaddrs1, da_node) {
401		sa1 = (struct sockaddr *)&da1->da_addr;
402		match = false;
403		list_for_each_entry(da2, dsaddrs2, da_node) {
404			sa2 = (struct sockaddr *)&da2->da_addr;
405			match = same_sockaddr(sa1, sa2);
406			if (match)
407				break;
408		}
409		if (!match)
410			break;
411	}
412	return match;
413}
414
415/*
416 * Lookup DS by addresses.  nfs4_ds_cache_lock is held
417 */
418static struct nfs4_pnfs_ds *
419_data_server_lookup_locked(const struct list_head *dsaddrs)
420{
421	struct nfs4_pnfs_ds *ds;
422
423	list_for_each_entry(ds, &nfs4_data_server_cache, ds_node)
424		if (_same_data_server_addrs_locked(&ds->ds_addrs, dsaddrs))
425			return ds;
426	return NULL;
427}
428
429static void destroy_ds(struct nfs4_pnfs_ds *ds)
430{
431	struct nfs4_pnfs_ds_addr *da;
432
433	dprintk("--> %s\n", __func__);
434	ifdebug(FACILITY)
435		print_ds(ds);
436
437	nfs_put_client(ds->ds_clp);
438
439	while (!list_empty(&ds->ds_addrs)) {
440		da = list_first_entry(&ds->ds_addrs,
441				      struct nfs4_pnfs_ds_addr,
442				      da_node);
443		list_del_init(&da->da_node);
444		kfree(da->da_remotestr);
445		kfree(da);
446	}
447
448	kfree(ds->ds_remotestr);
449	kfree(ds);
450}
451
452void nfs4_pnfs_ds_put(struct nfs4_pnfs_ds *ds)
453{
454	if (refcount_dec_and_lock(&ds->ds_count,
455				&nfs4_ds_cache_lock)) {
456		list_del_init(&ds->ds_node);
457		spin_unlock(&nfs4_ds_cache_lock);
458		destroy_ds(ds);
459	}
460}
461EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_put);
462
463/*
464 * Create a string with a human readable address and port to avoid
465 * complicated setup around many dprinks.
466 */
467static char *
468nfs4_pnfs_remotestr(struct list_head *dsaddrs, gfp_t gfp_flags)
469{
470	struct nfs4_pnfs_ds_addr *da;
471	char *remotestr;
472	size_t len;
473	char *p;
474
475	len = 3;        /* '{', '}' and eol */
476	list_for_each_entry(da, dsaddrs, da_node) {
477		len += strlen(da->da_remotestr) + 1;    /* string plus comma */
478	}
479
480	remotestr = kzalloc(len, gfp_flags);
481	if (!remotestr)
482		return NULL;
483
484	p = remotestr;
485	*(p++) = '{';
486	len--;
487	list_for_each_entry(da, dsaddrs, da_node) {
488		size_t ll = strlen(da->da_remotestr);
489
490		if (ll > len)
491			goto out_err;
492
493		memcpy(p, da->da_remotestr, ll);
494		p += ll;
495		len -= ll;
496
497		if (len < 1)
498			goto out_err;
499		(*p++) = ',';
500		len--;
501	}
502	if (len < 2)
503		goto out_err;
504	*(p++) = '}';
505	*p = '\0';
506	return remotestr;
507out_err:
508	kfree(remotestr);
509	return NULL;
510}
511
512/*
513 * Given a list of multipath struct nfs4_pnfs_ds_addr, add it to ds cache if
514 * uncached and return cached struct nfs4_pnfs_ds.
515 */
516struct nfs4_pnfs_ds *
517nfs4_pnfs_ds_add(struct list_head *dsaddrs, gfp_t gfp_flags)
518{
519	struct nfs4_pnfs_ds *tmp_ds, *ds = NULL;
520	char *remotestr;
521
522	if (list_empty(dsaddrs)) {
523		dprintk("%s: no addresses defined\n", __func__);
524		goto out;
525	}
526
527	ds = kzalloc(sizeof(*ds), gfp_flags);
528	if (!ds)
529		goto out;
530
531	/* this is only used for debugging, so it's ok if its NULL */
532	remotestr = nfs4_pnfs_remotestr(dsaddrs, gfp_flags);
533
534	spin_lock(&nfs4_ds_cache_lock);
535	tmp_ds = _data_server_lookup_locked(dsaddrs);
536	if (tmp_ds == NULL) {
537		INIT_LIST_HEAD(&ds->ds_addrs);
538		list_splice_init(dsaddrs, &ds->ds_addrs);
539		ds->ds_remotestr = remotestr;
540		refcount_set(&ds->ds_count, 1);
541		INIT_LIST_HEAD(&ds->ds_node);
542		ds->ds_clp = NULL;
543		list_add(&ds->ds_node, &nfs4_data_server_cache);
544		dprintk("%s add new data server %s\n", __func__,
545			ds->ds_remotestr);
546	} else {
547		kfree(remotestr);
548		kfree(ds);
549		refcount_inc(&tmp_ds->ds_count);
550		dprintk("%s data server %s found, inc'ed ds_count to %d\n",
551			__func__, tmp_ds->ds_remotestr,
552			refcount_read(&tmp_ds->ds_count));
553		ds = tmp_ds;
554	}
555	spin_unlock(&nfs4_ds_cache_lock);
556out:
557	return ds;
558}
559EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_add);
560
561static void nfs4_wait_ds_connect(struct nfs4_pnfs_ds *ds)
562{
563	might_sleep();
564	wait_on_bit(&ds->ds_state, NFS4DS_CONNECTING,
565			TASK_KILLABLE);
566}
567
568static void nfs4_clear_ds_conn_bit(struct nfs4_pnfs_ds *ds)
569{
570	smp_mb__before_atomic();
571	clear_bit(NFS4DS_CONNECTING, &ds->ds_state);
572	smp_mb__after_atomic();
573	wake_up_bit(&ds->ds_state, NFS4DS_CONNECTING);
574}
575
576static struct nfs_client *(*get_v3_ds_connect)(
577			struct nfs_server *mds_srv,
578			const struct sockaddr *ds_addr,
579			int ds_addrlen,
580			int ds_proto,
581			unsigned int ds_timeo,
582			unsigned int ds_retrans);
583
584static bool load_v3_ds_connect(void)
585{
586	if (!get_v3_ds_connect) {
587		get_v3_ds_connect = symbol_request(nfs3_set_ds_client);
588		WARN_ON_ONCE(!get_v3_ds_connect);
589	}
590
591	return(get_v3_ds_connect != NULL);
592}
593
594void nfs4_pnfs_v3_ds_connect_unload(void)
595{
596	if (get_v3_ds_connect) {
597		symbol_put(nfs3_set_ds_client);
598		get_v3_ds_connect = NULL;
599	}
600}
 
601
602static int _nfs4_pnfs_v3_ds_connect(struct nfs_server *mds_srv,
603				 struct nfs4_pnfs_ds *ds,
604				 unsigned int timeo,
605				 unsigned int retrans)
606{
607	struct nfs_client *clp = ERR_PTR(-EIO);
608	struct nfs4_pnfs_ds_addr *da;
609	int status = 0;
610
611	dprintk("--> %s DS %s\n", __func__, ds->ds_remotestr);
612
613	if (!load_v3_ds_connect())
614		goto out;
615
616	list_for_each_entry(da, &ds->ds_addrs, da_node) {
617		dprintk("%s: DS %s: trying address %s\n",
618			__func__, ds->ds_remotestr, da->da_remotestr);
619
620		if (!IS_ERR(clp)) {
621			struct xprt_create xprt_args = {
622				.ident = XPRT_TRANSPORT_TCP,
623				.net = clp->cl_net,
624				.dstaddr = (struct sockaddr *)&da->da_addr,
625				.addrlen = da->da_addrlen,
626				.servername = clp->cl_hostname,
627			};
628			/* Add this address as an alias */
629			rpc_clnt_add_xprt(clp->cl_rpcclient, &xprt_args,
630					rpc_clnt_test_and_add_xprt, NULL);
631		} else
632			clp = get_v3_ds_connect(mds_srv,
633					(struct sockaddr *)&da->da_addr,
634					da->da_addrlen, IPPROTO_TCP,
635					timeo, retrans);
636	}
637
638	if (IS_ERR(clp)) {
639		status = PTR_ERR(clp);
640		goto out;
641	}
642
643	smp_wmb();
644	ds->ds_clp = clp;
645	dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
646out:
647	return status;
648}
649
650static int _nfs4_pnfs_v4_ds_connect(struct nfs_server *mds_srv,
651				 struct nfs4_pnfs_ds *ds,
652				 unsigned int timeo,
653				 unsigned int retrans,
654				 u32 minor_version)
655{
656	struct nfs_client *clp = ERR_PTR(-EIO);
657	struct nfs4_pnfs_ds_addr *da;
658	int status = 0;
659
660	dprintk("--> %s DS %s\n", __func__, ds->ds_remotestr);
661
662	list_for_each_entry(da, &ds->ds_addrs, da_node) {
663		dprintk("%s: DS %s: trying address %s\n",
664			__func__, ds->ds_remotestr, da->da_remotestr);
665
666		if (!IS_ERR(clp) && clp->cl_mvops->session_trunk) {
667			struct xprt_create xprt_args = {
668				.ident = XPRT_TRANSPORT_TCP,
669				.net = clp->cl_net,
670				.dstaddr = (struct sockaddr *)&da->da_addr,
671				.addrlen = da->da_addrlen,
672				.servername = clp->cl_hostname,
673			};
674			struct nfs4_add_xprt_data xprtdata = {
675				.clp = clp,
676				.cred = nfs4_get_clid_cred(clp),
677			};
678			struct rpc_add_xprt_test rpcdata = {
679				.add_xprt_test = clp->cl_mvops->session_trunk,
680				.data = &xprtdata,
681			};
682
683			/**
684			* Test this address for session trunking and
685			* add as an alias
686			*/
687			rpc_clnt_add_xprt(clp->cl_rpcclient, &xprt_args,
688					  rpc_clnt_setup_test_and_add_xprt,
689					  &rpcdata);
690			if (xprtdata.cred)
691				put_rpccred(xprtdata.cred);
692		} else {
693			clp = nfs4_set_ds_client(mds_srv,
694						(struct sockaddr *)&da->da_addr,
695						da->da_addrlen, IPPROTO_TCP,
696						timeo, retrans, minor_version);
697			if (IS_ERR(clp))
698				continue;
699
700			status = nfs4_init_ds_session(clp,
701					mds_srv->nfs_client->cl_lease_time);
702			if (status) {
703				nfs_put_client(clp);
704				clp = ERR_PTR(-EIO);
705				continue;
706			}
707
708		}
709	}
710
711	if (IS_ERR(clp)) {
712		status = PTR_ERR(clp);
713		goto out;
714	}
715
716	smp_wmb();
717	ds->ds_clp = clp;
718	dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
719out:
720	return status;
721}
722
723/*
724 * Create an rpc connection to the nfs4_pnfs_ds data server.
725 * Currently only supports IPv4 and IPv6 addresses.
726 * If connection fails, make devid unavailable and return a -errno.
727 */
728int nfs4_pnfs_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds,
729			  struct nfs4_deviceid_node *devid, unsigned int timeo,
730			  unsigned int retrans, u32 version, u32 minor_version)
731{
732	int err;
733
734again:
735	err = 0;
736	if (test_and_set_bit(NFS4DS_CONNECTING, &ds->ds_state) == 0) {
 
 
737		if (version == 3) {
738			err = _nfs4_pnfs_v3_ds_connect(mds_srv, ds, timeo,
739						       retrans);
740		} else if (version == 4) {
741			err = _nfs4_pnfs_v4_ds_connect(mds_srv, ds, timeo,
742						       retrans, minor_version);
743		} else {
744			dprintk("%s: unsupported DS version %d\n", __func__,
745				version);
746			err = -EPROTONOSUPPORT;
747		}
748
 
 
749		nfs4_clear_ds_conn_bit(ds);
750	} else {
751		nfs4_wait_ds_connect(ds);
752
753		/* what was waited on didn't connect AND didn't mark unavail */
754		if (!ds->ds_clp && !nfs4_test_deviceid_unavailable(devid))
755			goto again;
756	}
757
758	/*
759	 * At this point the ds->ds_clp should be ready, but it might have
760	 * hit an error.
761	 */
762	if (!err) {
763		if (!ds->ds_clp || !nfs_client_init_is_complete(ds->ds_clp)) {
764			WARN_ON_ONCE(ds->ds_clp ||
765				!nfs4_test_deviceid_unavailable(devid));
766			return -EINVAL;
767		}
768		err = nfs_client_init_status(ds->ds_clp);
769	}
770
771	return err;
772}
773EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_connect);
774
775/*
776 * Currently only supports ipv4, ipv6 and one multi-path address.
777 */
778struct nfs4_pnfs_ds_addr *
779nfs4_decode_mp_ds_addr(struct net *net, struct xdr_stream *xdr, gfp_t gfp_flags)
780{
781	struct nfs4_pnfs_ds_addr *da = NULL;
782	char *buf, *portstr;
783	__be16 port;
784	int nlen, rlen;
785	int tmp[2];
786	__be32 *p;
787	char *netid, *match_netid;
788	size_t len, match_netid_len;
789	char *startsep = "";
790	char *endsep = "";
791
792
793	/* r_netid */
794	p = xdr_inline_decode(xdr, 4);
795	if (unlikely(!p))
796		goto out_err;
797	nlen = be32_to_cpup(p++);
798
799	p = xdr_inline_decode(xdr, nlen);
800	if (unlikely(!p))
801		goto out_err;
802
803	netid = kmalloc(nlen+1, gfp_flags);
804	if (unlikely(!netid))
805		goto out_err;
806
807	netid[nlen] = '\0';
808	memcpy(netid, p, nlen);
809
810	/* r_addr: ip/ip6addr with port in dec octets - see RFC 5665 */
811	p = xdr_inline_decode(xdr, 4);
812	if (unlikely(!p))
813		goto out_free_netid;
814	rlen = be32_to_cpup(p);
815
816	p = xdr_inline_decode(xdr, rlen);
817	if (unlikely(!p))
818		goto out_free_netid;
819
820	/* port is ".ABC.DEF", 8 chars max */
821	if (rlen > INET6_ADDRSTRLEN + IPV6_SCOPE_ID_LEN + 8) {
822		dprintk("%s: Invalid address, length %d\n", __func__,
823			rlen);
824		goto out_free_netid;
825	}
826	buf = kmalloc(rlen + 1, gfp_flags);
827	if (!buf) {
828		dprintk("%s: Not enough memory\n", __func__);
829		goto out_free_netid;
830	}
831	buf[rlen] = '\0';
832	memcpy(buf, p, rlen);
833
834	/* replace port '.' with '-' */
835	portstr = strrchr(buf, '.');
836	if (!portstr) {
837		dprintk("%s: Failed finding expected dot in port\n",
838			__func__);
839		goto out_free_buf;
840	}
841	*portstr = '-';
842
843	/* find '.' between address and port */
844	portstr = strrchr(buf, '.');
845	if (!portstr) {
846		dprintk("%s: Failed finding expected dot between address and "
847			"port\n", __func__);
848		goto out_free_buf;
849	}
850	*portstr = '\0';
851
852	da = kzalloc(sizeof(*da), gfp_flags);
853	if (unlikely(!da))
854		goto out_free_buf;
855
856	INIT_LIST_HEAD(&da->da_node);
857
858	if (!rpc_pton(net, buf, portstr-buf, (struct sockaddr *)&da->da_addr,
859		      sizeof(da->da_addr))) {
860		dprintk("%s: error parsing address %s\n", __func__, buf);
861		goto out_free_da;
862	}
863
864	portstr++;
865	sscanf(portstr, "%d-%d", &tmp[0], &tmp[1]);
866	port = htons((tmp[0] << 8) | (tmp[1]));
867
868	switch (da->da_addr.ss_family) {
869	case AF_INET:
870		((struct sockaddr_in *)&da->da_addr)->sin_port = port;
871		da->da_addrlen = sizeof(struct sockaddr_in);
872		match_netid = "tcp";
873		match_netid_len = 3;
874		break;
875
876	case AF_INET6:
877		((struct sockaddr_in6 *)&da->da_addr)->sin6_port = port;
878		da->da_addrlen = sizeof(struct sockaddr_in6);
879		match_netid = "tcp6";
880		match_netid_len = 4;
881		startsep = "[";
882		endsep = "]";
883		break;
884
885	default:
886		dprintk("%s: unsupported address family: %u\n",
887			__func__, da->da_addr.ss_family);
888		goto out_free_da;
889	}
890
891	if (nlen != match_netid_len || strncmp(netid, match_netid, nlen)) {
892		dprintk("%s: ERROR: r_netid \"%s\" != \"%s\"\n",
893			__func__, netid, match_netid);
894		goto out_free_da;
895	}
896
897	/* save human readable address */
898	len = strlen(startsep) + strlen(buf) + strlen(endsep) + 7;
899	da->da_remotestr = kzalloc(len, gfp_flags);
900
901	/* NULL is ok, only used for dprintk */
902	if (da->da_remotestr)
903		snprintf(da->da_remotestr, len, "%s%s%s:%u", startsep,
904			 buf, endsep, ntohs(port));
905
906	dprintk("%s: Parsed DS addr %s\n", __func__, da->da_remotestr);
907	kfree(buf);
908	kfree(netid);
909	return da;
910
911out_free_da:
912	kfree(da);
913out_free_buf:
914	dprintk("%s: Error parsing DS addr: %s\n", __func__, buf);
915	kfree(buf);
916out_free_netid:
917	kfree(netid);
918out_err:
919	return NULL;
920}
921EXPORT_SYMBOL_GPL(nfs4_decode_mp_ds_addr);
922
923void
924pnfs_layout_mark_request_commit(struct nfs_page *req,
925				struct pnfs_layout_segment *lseg,
926				struct nfs_commit_info *cinfo,
927				u32 ds_commit_idx)
928{
929	struct list_head *list;
930	struct pnfs_commit_bucket *buckets;
931
932	mutex_lock(&NFS_I(cinfo->inode)->commit_mutex);
933	buckets = cinfo->ds->buckets;
934	list = &buckets[ds_commit_idx].written;
935	if (list_empty(list)) {
936		if (!pnfs_is_valid_lseg(lseg)) {
937			mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
938			cinfo->completion_ops->resched_write(cinfo, req);
939			return;
940		}
941		/* Non-empty buckets hold a reference on the lseg.  That ref
942		 * is normally transferred to the COMMIT call and released
943		 * there.  It could also be released if the last req is pulled
944		 * off due to a rewrite, in which case it will be done in
945		 * pnfs_common_clear_request_commit
946		 */
947		WARN_ON_ONCE(buckets[ds_commit_idx].wlseg != NULL);
948		buckets[ds_commit_idx].wlseg = pnfs_get_lseg(lseg);
949	}
950	set_bit(PG_COMMIT_TO_DS, &req->wb_flags);
951	cinfo->ds->nwritten++;
952
953	nfs_request_add_commit_list_locked(req, list, cinfo);
954	mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
955	nfs_mark_page_unstable(req->wb_page, cinfo);
956}
957EXPORT_SYMBOL_GPL(pnfs_layout_mark_request_commit);
958
959int
960pnfs_nfs_generic_sync(struct inode *inode, bool datasync)
961{
962	int ret;
963
964	if (!pnfs_layoutcommit_outstanding(inode))
965		return 0;
966	ret = nfs_commit_inode(inode, FLUSH_SYNC);
967	if (ret < 0)
968		return ret;
969	if (datasync)
970		return 0;
971	return pnfs_layoutcommit_inode(inode, true);
972}
973EXPORT_SYMBOL_GPL(pnfs_nfs_generic_sync);
974
v4.10.11
  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
 21void 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}
 28EXPORT_SYMBOL_GPL(pnfs_generic_rw_release);
 29
 30/* Fake up some data that will cause nfs_commit_release to retry the writes. */
 31void 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}
 40EXPORT_SYMBOL_GPL(pnfs_generic_prepare_to_resend_writes);
 41
 42void 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}
 49EXPORT_SYMBOL_GPL(pnfs_generic_write_commit_done);
 50
 51void 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}
 60EXPORT_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 */
 66void
 67pnfs_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	}
 84out:
 85	nfs_request_remove_commit_list(req, cinfo);
 86	pnfs_put_lseg_locked(freeme);
 87}
 88EXPORT_SYMBOL_GPL(pnfs_generic_clear_request_commit);
 89
 90static int
 91pnfs_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
113static int
114pnfs_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 */
140int 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}
154EXPORT_SYMBOL_GPL(pnfs_generic_scan_commit_lists);
155
156/* Pull everything off the committing lists and dump into @dst.  */
157void 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);
165restart:
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}
179EXPORT_SYMBOL_GPL(pnfs_generic_recover_commit_reqs);
180
181static 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
205static unsigned int
206pnfs_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
233static inline
234void 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 *
252 * This must be called instead of nfs_init_commit - call one or the other, but
253 * not both!
254 */
255static bool
256pnfs_generic_commit_cancel_empty_pagelist(struct list_head *pages,
257					  struct nfs_commit_data *data,
258					  struct nfs_commit_info *cinfo)
259{
260	if (list_empty(pages)) {
261		if (atomic_dec_and_test(&cinfo->mds->rpcs_out))
262			wake_up_atomic_t(&cinfo->mds->rpcs_out);
263		/* don't call nfs_commitdata_release - it tries to put
264		 * the open_context which is not acquired until nfs_init_commit
265		 * which has not been called on @data */
266		WARN_ON_ONCE(data->context);
267		nfs_commit_free(data);
268		return true;
269	}
270
271	return false;
272}
273
274/* This follows nfs_commit_list pretty closely */
275int
276pnfs_generic_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
277			     int how, struct nfs_commit_info *cinfo,
278			     int (*initiate_commit)(struct nfs_commit_data *data,
279						    int how))
280{
281	struct nfs_commit_data *data, *tmp;
282	LIST_HEAD(list);
283	unsigned int nreq = 0;
284
285	if (!list_empty(mds_pages)) {
286		data = nfs_commitdata_alloc();
287		if (data != NULL) {
288			data->ds_commit_index = -1;
289			list_add(&data->pages, &list);
290			nreq++;
291		} else {
292			nfs_retry_commit(mds_pages, NULL, cinfo, 0);
293			pnfs_generic_retry_commit(cinfo, 0);
294			return -ENOMEM;
295		}
296	}
297
298	nreq += pnfs_generic_alloc_ds_commits(cinfo, &list);
299
300	if (nreq == 0)
301		goto out;
302
303	atomic_add(nreq, &cinfo->mds->rpcs_out);
304
305	list_for_each_entry_safe(data, tmp, &list, pages) {
306		list_del_init(&data->pages);
307		if (data->ds_commit_index < 0) {
308			/* another commit raced with us */
309			if (pnfs_generic_commit_cancel_empty_pagelist(mds_pages,
310				data, cinfo))
311				continue;
312
313			nfs_init_commit(data, mds_pages, NULL, cinfo);
314			nfs_initiate_commit(NFS_CLIENT(inode), data,
315					    NFS_PROTO(data->inode),
316					    data->mds_ops, how, 0);
317		} else {
318			LIST_HEAD(pages);
319
320			pnfs_fetch_commit_bucket_list(&pages, data, cinfo);
321
322			/* another commit raced with us */
323			if (pnfs_generic_commit_cancel_empty_pagelist(&pages,
324				data, cinfo))
325				continue;
326
327			nfs_init_commit(data, &pages, data->lseg, cinfo);
328			initiate_commit(data, how);
329		}
330	}
331out:
332	cinfo->ds->ncommitting = 0;
333	return PNFS_ATTEMPTED;
334}
335EXPORT_SYMBOL_GPL(pnfs_generic_commit_pagelist);
336
337/*
338 * Data server cache
339 *
340 * Data servers can be mapped to different device ids.
341 * nfs4_pnfs_ds reference counting
342 *   - set to 1 on allocation
343 *   - incremented when a device id maps a data server already in the cache.
344 *   - decremented when deviceid is removed from the cache.
345 */
346static DEFINE_SPINLOCK(nfs4_ds_cache_lock);
347static LIST_HEAD(nfs4_data_server_cache);
348
349/* Debug routines */
350static void
351print_ds(struct nfs4_pnfs_ds *ds)
352{
353	if (ds == NULL) {
354		printk(KERN_WARNING "%s NULL device\n", __func__);
355		return;
356	}
357	printk(KERN_WARNING "        ds %s\n"
358		"        ref count %d\n"
359		"        client %p\n"
360		"        cl_exchange_flags %x\n",
361		ds->ds_remotestr,
362		atomic_read(&ds->ds_count), ds->ds_clp,
363		ds->ds_clp ? ds->ds_clp->cl_exchange_flags : 0);
364}
365
366static bool
367same_sockaddr(struct sockaddr *addr1, struct sockaddr *addr2)
368{
369	struct sockaddr_in *a, *b;
370	struct sockaddr_in6 *a6, *b6;
371
372	if (addr1->sa_family != addr2->sa_family)
373		return false;
374
375	switch (addr1->sa_family) {
376	case AF_INET:
377		a = (struct sockaddr_in *)addr1;
378		b = (struct sockaddr_in *)addr2;
379
380		if (a->sin_addr.s_addr == b->sin_addr.s_addr &&
381		    a->sin_port == b->sin_port)
382			return true;
383		break;
384
385	case AF_INET6:
386		a6 = (struct sockaddr_in6 *)addr1;
387		b6 = (struct sockaddr_in6 *)addr2;
388
389		/* LINKLOCAL addresses must have matching scope_id */
390		if (ipv6_addr_src_scope(&a6->sin6_addr) ==
391		    IPV6_ADDR_SCOPE_LINKLOCAL &&
392		    a6->sin6_scope_id != b6->sin6_scope_id)
393			return false;
394
395		if (ipv6_addr_equal(&a6->sin6_addr, &b6->sin6_addr) &&
396		    a6->sin6_port == b6->sin6_port)
397			return true;
398		break;
399
400	default:
401		dprintk("%s: unhandled address family: %u\n",
402			__func__, addr1->sa_family);
403		return false;
404	}
405
406	return false;
407}
408
409/*
410 * Checks if 'dsaddrs1' contains a subset of 'dsaddrs2'. If it does,
411 * declare a match.
412 */
413static bool
414_same_data_server_addrs_locked(const struct list_head *dsaddrs1,
415			       const struct list_head *dsaddrs2)
416{
417	struct nfs4_pnfs_ds_addr *da1, *da2;
418	struct sockaddr *sa1, *sa2;
419	bool match = false;
420
421	list_for_each_entry(da1, dsaddrs1, da_node) {
422		sa1 = (struct sockaddr *)&da1->da_addr;
423		match = false;
424		list_for_each_entry(da2, dsaddrs2, da_node) {
425			sa2 = (struct sockaddr *)&da2->da_addr;
426			match = same_sockaddr(sa1, sa2);
427			if (match)
428				break;
429		}
430		if (!match)
431			break;
432	}
433	return match;
434}
435
436/*
437 * Lookup DS by addresses.  nfs4_ds_cache_lock is held
438 */
439static struct nfs4_pnfs_ds *
440_data_server_lookup_locked(const struct list_head *dsaddrs)
441{
442	struct nfs4_pnfs_ds *ds;
443
444	list_for_each_entry(ds, &nfs4_data_server_cache, ds_node)
445		if (_same_data_server_addrs_locked(&ds->ds_addrs, dsaddrs))
446			return ds;
447	return NULL;
448}
449
450static void destroy_ds(struct nfs4_pnfs_ds *ds)
451{
452	struct nfs4_pnfs_ds_addr *da;
453
454	dprintk("--> %s\n", __func__);
455	ifdebug(FACILITY)
456		print_ds(ds);
457
458	nfs_put_client(ds->ds_clp);
459
460	while (!list_empty(&ds->ds_addrs)) {
461		da = list_first_entry(&ds->ds_addrs,
462				      struct nfs4_pnfs_ds_addr,
463				      da_node);
464		list_del_init(&da->da_node);
465		kfree(da->da_remotestr);
466		kfree(da);
467	}
468
469	kfree(ds->ds_remotestr);
470	kfree(ds);
471}
472
473void nfs4_pnfs_ds_put(struct nfs4_pnfs_ds *ds)
474{
475	if (atomic_dec_and_lock(&ds->ds_count,
476				&nfs4_ds_cache_lock)) {
477		list_del_init(&ds->ds_node);
478		spin_unlock(&nfs4_ds_cache_lock);
479		destroy_ds(ds);
480	}
481}
482EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_put);
483
484/*
485 * Create a string with a human readable address and port to avoid
486 * complicated setup around many dprinks.
487 */
488static char *
489nfs4_pnfs_remotestr(struct list_head *dsaddrs, gfp_t gfp_flags)
490{
491	struct nfs4_pnfs_ds_addr *da;
492	char *remotestr;
493	size_t len;
494	char *p;
495
496	len = 3;        /* '{', '}' and eol */
497	list_for_each_entry(da, dsaddrs, da_node) {
498		len += strlen(da->da_remotestr) + 1;    /* string plus comma */
499	}
500
501	remotestr = kzalloc(len, gfp_flags);
502	if (!remotestr)
503		return NULL;
504
505	p = remotestr;
506	*(p++) = '{';
507	len--;
508	list_for_each_entry(da, dsaddrs, da_node) {
509		size_t ll = strlen(da->da_remotestr);
510
511		if (ll > len)
512			goto out_err;
513
514		memcpy(p, da->da_remotestr, ll);
515		p += ll;
516		len -= ll;
517
518		if (len < 1)
519			goto out_err;
520		(*p++) = ',';
521		len--;
522	}
523	if (len < 2)
524		goto out_err;
525	*(p++) = '}';
526	*p = '\0';
527	return remotestr;
528out_err:
529	kfree(remotestr);
530	return NULL;
531}
532
533/*
534 * Given a list of multipath struct nfs4_pnfs_ds_addr, add it to ds cache if
535 * uncached and return cached struct nfs4_pnfs_ds.
536 */
537struct nfs4_pnfs_ds *
538nfs4_pnfs_ds_add(struct list_head *dsaddrs, gfp_t gfp_flags)
539{
540	struct nfs4_pnfs_ds *tmp_ds, *ds = NULL;
541	char *remotestr;
542
543	if (list_empty(dsaddrs)) {
544		dprintk("%s: no addresses defined\n", __func__);
545		goto out;
546	}
547
548	ds = kzalloc(sizeof(*ds), gfp_flags);
549	if (!ds)
550		goto out;
551
552	/* this is only used for debugging, so it's ok if its NULL */
553	remotestr = nfs4_pnfs_remotestr(dsaddrs, gfp_flags);
554
555	spin_lock(&nfs4_ds_cache_lock);
556	tmp_ds = _data_server_lookup_locked(dsaddrs);
557	if (tmp_ds == NULL) {
558		INIT_LIST_HEAD(&ds->ds_addrs);
559		list_splice_init(dsaddrs, &ds->ds_addrs);
560		ds->ds_remotestr = remotestr;
561		atomic_set(&ds->ds_count, 1);
562		INIT_LIST_HEAD(&ds->ds_node);
563		ds->ds_clp = NULL;
564		list_add(&ds->ds_node, &nfs4_data_server_cache);
565		dprintk("%s add new data server %s\n", __func__,
566			ds->ds_remotestr);
567	} else {
568		kfree(remotestr);
569		kfree(ds);
570		atomic_inc(&tmp_ds->ds_count);
571		dprintk("%s data server %s found, inc'ed ds_count to %d\n",
572			__func__, tmp_ds->ds_remotestr,
573			atomic_read(&tmp_ds->ds_count));
574		ds = tmp_ds;
575	}
576	spin_unlock(&nfs4_ds_cache_lock);
577out:
578	return ds;
579}
580EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_add);
581
582static void nfs4_wait_ds_connect(struct nfs4_pnfs_ds *ds)
583{
584	might_sleep();
585	wait_on_bit(&ds->ds_state, NFS4DS_CONNECTING,
586			TASK_KILLABLE);
587}
588
589static void nfs4_clear_ds_conn_bit(struct nfs4_pnfs_ds *ds)
590{
591	smp_mb__before_atomic();
592	clear_bit(NFS4DS_CONNECTING, &ds->ds_state);
593	smp_mb__after_atomic();
594	wake_up_bit(&ds->ds_state, NFS4DS_CONNECTING);
595}
596
597static struct nfs_client *(*get_v3_ds_connect)(
598			struct nfs_server *mds_srv,
599			const struct sockaddr *ds_addr,
600			int ds_addrlen,
601			int ds_proto,
602			unsigned int ds_timeo,
603			unsigned int ds_retrans);
604
605static bool load_v3_ds_connect(void)
606{
607	if (!get_v3_ds_connect) {
608		get_v3_ds_connect = symbol_request(nfs3_set_ds_client);
609		WARN_ON_ONCE(!get_v3_ds_connect);
610	}
611
612	return(get_v3_ds_connect != NULL);
613}
614
615void nfs4_pnfs_v3_ds_connect_unload(void)
616{
617	if (get_v3_ds_connect) {
618		symbol_put(nfs3_set_ds_client);
619		get_v3_ds_connect = NULL;
620	}
621}
622EXPORT_SYMBOL_GPL(nfs4_pnfs_v3_ds_connect_unload);
623
624static int _nfs4_pnfs_v3_ds_connect(struct nfs_server *mds_srv,
625				 struct nfs4_pnfs_ds *ds,
626				 unsigned int timeo,
627				 unsigned int retrans)
628{
629	struct nfs_client *clp = ERR_PTR(-EIO);
630	struct nfs4_pnfs_ds_addr *da;
631	int status = 0;
632
633	dprintk("--> %s DS %s\n", __func__, ds->ds_remotestr);
634
635	if (!load_v3_ds_connect())
636		goto out;
637
638	list_for_each_entry(da, &ds->ds_addrs, da_node) {
639		dprintk("%s: DS %s: trying address %s\n",
640			__func__, ds->ds_remotestr, da->da_remotestr);
641
642		if (!IS_ERR(clp)) {
643			struct xprt_create xprt_args = {
644				.ident = XPRT_TRANSPORT_TCP,
645				.net = clp->cl_net,
646				.dstaddr = (struct sockaddr *)&da->da_addr,
647				.addrlen = da->da_addrlen,
648				.servername = clp->cl_hostname,
649			};
650			/* Add this address as an alias */
651			rpc_clnt_add_xprt(clp->cl_rpcclient, &xprt_args,
652					rpc_clnt_test_and_add_xprt, NULL);
653		} else
654			clp = get_v3_ds_connect(mds_srv,
655					(struct sockaddr *)&da->da_addr,
656					da->da_addrlen, IPPROTO_TCP,
657					timeo, retrans);
658	}
659
660	if (IS_ERR(clp)) {
661		status = PTR_ERR(clp);
662		goto out;
663	}
664
665	smp_wmb();
666	ds->ds_clp = clp;
667	dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
668out:
669	return status;
670}
671
672static int _nfs4_pnfs_v4_ds_connect(struct nfs_server *mds_srv,
673				 struct nfs4_pnfs_ds *ds,
674				 unsigned int timeo,
675				 unsigned int retrans,
676				 u32 minor_version)
677{
678	struct nfs_client *clp = ERR_PTR(-EIO);
679	struct nfs4_pnfs_ds_addr *da;
680	int status = 0;
681
682	dprintk("--> %s DS %s\n", __func__, ds->ds_remotestr);
683
684	list_for_each_entry(da, &ds->ds_addrs, da_node) {
685		dprintk("%s: DS %s: trying address %s\n",
686			__func__, ds->ds_remotestr, da->da_remotestr);
687
688		if (!IS_ERR(clp) && clp->cl_mvops->session_trunk) {
689			struct xprt_create xprt_args = {
690				.ident = XPRT_TRANSPORT_TCP,
691				.net = clp->cl_net,
692				.dstaddr = (struct sockaddr *)&da->da_addr,
693				.addrlen = da->da_addrlen,
694				.servername = clp->cl_hostname,
695			};
696			struct nfs4_add_xprt_data xprtdata = {
697				.clp = clp,
698				.cred = nfs4_get_clid_cred(clp),
699			};
700			struct rpc_add_xprt_test rpcdata = {
701				.add_xprt_test = clp->cl_mvops->session_trunk,
702				.data = &xprtdata,
703			};
704
705			/**
706			* Test this address for session trunking and
707			* add as an alias
708			*/
709			rpc_clnt_add_xprt(clp->cl_rpcclient, &xprt_args,
710					  rpc_clnt_setup_test_and_add_xprt,
711					  &rpcdata);
712			if (xprtdata.cred)
713				put_rpccred(xprtdata.cred);
714		} else {
715			clp = nfs4_set_ds_client(mds_srv,
716						(struct sockaddr *)&da->da_addr,
717						da->da_addrlen, IPPROTO_TCP,
718						timeo, retrans, minor_version);
719			if (IS_ERR(clp))
720				continue;
721
722			status = nfs4_init_ds_session(clp,
723					mds_srv->nfs_client->cl_lease_time);
724			if (status) {
725				nfs_put_client(clp);
726				clp = ERR_PTR(-EIO);
727				continue;
728			}
729
730		}
731	}
732
733	if (IS_ERR(clp)) {
734		status = PTR_ERR(clp);
735		goto out;
736	}
737
738	smp_wmb();
739	ds->ds_clp = clp;
740	dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
741out:
742	return status;
743}
744
745/*
746 * Create an rpc connection to the nfs4_pnfs_ds data server.
747 * Currently only supports IPv4 and IPv6 addresses.
748 * If connection fails, make devid unavailable.
749 */
750void nfs4_pnfs_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds,
751			  struct nfs4_deviceid_node *devid, unsigned int timeo,
752			  unsigned int retrans, u32 version, u32 minor_version)
753{
 
 
 
 
754	if (test_and_set_bit(NFS4DS_CONNECTING, &ds->ds_state) == 0) {
755		int err = 0;
756
757		if (version == 3) {
758			err = _nfs4_pnfs_v3_ds_connect(mds_srv, ds, timeo,
759						       retrans);
760		} else if (version == 4) {
761			err = _nfs4_pnfs_v4_ds_connect(mds_srv, ds, timeo,
762						       retrans, minor_version);
763		} else {
764			dprintk("%s: unsupported DS version %d\n", __func__,
765				version);
766			err = -EPROTONOSUPPORT;
767		}
768
769		if (err)
770			nfs4_mark_deviceid_unavailable(devid);
771		nfs4_clear_ds_conn_bit(ds);
772	} else {
773		nfs4_wait_ds_connect(ds);
 
 
 
 
774	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
775}
776EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_connect);
777
778/*
779 * Currently only supports ipv4, ipv6 and one multi-path address.
780 */
781struct nfs4_pnfs_ds_addr *
782nfs4_decode_mp_ds_addr(struct net *net, struct xdr_stream *xdr, gfp_t gfp_flags)
783{
784	struct nfs4_pnfs_ds_addr *da = NULL;
785	char *buf, *portstr;
786	__be16 port;
787	int nlen, rlen;
788	int tmp[2];
789	__be32 *p;
790	char *netid, *match_netid;
791	size_t len, match_netid_len;
792	char *startsep = "";
793	char *endsep = "";
794
795
796	/* r_netid */
797	p = xdr_inline_decode(xdr, 4);
798	if (unlikely(!p))
799		goto out_err;
800	nlen = be32_to_cpup(p++);
801
802	p = xdr_inline_decode(xdr, nlen);
803	if (unlikely(!p))
804		goto out_err;
805
806	netid = kmalloc(nlen+1, gfp_flags);
807	if (unlikely(!netid))
808		goto out_err;
809
810	netid[nlen] = '\0';
811	memcpy(netid, p, nlen);
812
813	/* r_addr: ip/ip6addr with port in dec octets - see RFC 5665 */
814	p = xdr_inline_decode(xdr, 4);
815	if (unlikely(!p))
816		goto out_free_netid;
817	rlen = be32_to_cpup(p);
818
819	p = xdr_inline_decode(xdr, rlen);
820	if (unlikely(!p))
821		goto out_free_netid;
822
823	/* port is ".ABC.DEF", 8 chars max */
824	if (rlen > INET6_ADDRSTRLEN + IPV6_SCOPE_ID_LEN + 8) {
825		dprintk("%s: Invalid address, length %d\n", __func__,
826			rlen);
827		goto out_free_netid;
828	}
829	buf = kmalloc(rlen + 1, gfp_flags);
830	if (!buf) {
831		dprintk("%s: Not enough memory\n", __func__);
832		goto out_free_netid;
833	}
834	buf[rlen] = '\0';
835	memcpy(buf, p, rlen);
836
837	/* replace port '.' with '-' */
838	portstr = strrchr(buf, '.');
839	if (!portstr) {
840		dprintk("%s: Failed finding expected dot in port\n",
841			__func__);
842		goto out_free_buf;
843	}
844	*portstr = '-';
845
846	/* find '.' between address and port */
847	portstr = strrchr(buf, '.');
848	if (!portstr) {
849		dprintk("%s: Failed finding expected dot between address and "
850			"port\n", __func__);
851		goto out_free_buf;
852	}
853	*portstr = '\0';
854
855	da = kzalloc(sizeof(*da), gfp_flags);
856	if (unlikely(!da))
857		goto out_free_buf;
858
859	INIT_LIST_HEAD(&da->da_node);
860
861	if (!rpc_pton(net, buf, portstr-buf, (struct sockaddr *)&da->da_addr,
862		      sizeof(da->da_addr))) {
863		dprintk("%s: error parsing address %s\n", __func__, buf);
864		goto out_free_da;
865	}
866
867	portstr++;
868	sscanf(portstr, "%d-%d", &tmp[0], &tmp[1]);
869	port = htons((tmp[0] << 8) | (tmp[1]));
870
871	switch (da->da_addr.ss_family) {
872	case AF_INET:
873		((struct sockaddr_in *)&da->da_addr)->sin_port = port;
874		da->da_addrlen = sizeof(struct sockaddr_in);
875		match_netid = "tcp";
876		match_netid_len = 3;
877		break;
878
879	case AF_INET6:
880		((struct sockaddr_in6 *)&da->da_addr)->sin6_port = port;
881		da->da_addrlen = sizeof(struct sockaddr_in6);
882		match_netid = "tcp6";
883		match_netid_len = 4;
884		startsep = "[";
885		endsep = "]";
886		break;
887
888	default:
889		dprintk("%s: unsupported address family: %u\n",
890			__func__, da->da_addr.ss_family);
891		goto out_free_da;
892	}
893
894	if (nlen != match_netid_len || strncmp(netid, match_netid, nlen)) {
895		dprintk("%s: ERROR: r_netid \"%s\" != \"%s\"\n",
896			__func__, netid, match_netid);
897		goto out_free_da;
898	}
899
900	/* save human readable address */
901	len = strlen(startsep) + strlen(buf) + strlen(endsep) + 7;
902	da->da_remotestr = kzalloc(len, gfp_flags);
903
904	/* NULL is ok, only used for dprintk */
905	if (da->da_remotestr)
906		snprintf(da->da_remotestr, len, "%s%s%s:%u", startsep,
907			 buf, endsep, ntohs(port));
908
909	dprintk("%s: Parsed DS addr %s\n", __func__, da->da_remotestr);
910	kfree(buf);
911	kfree(netid);
912	return da;
913
914out_free_da:
915	kfree(da);
916out_free_buf:
917	dprintk("%s: Error parsing DS addr: %s\n", __func__, buf);
918	kfree(buf);
919out_free_netid:
920	kfree(netid);
921out_err:
922	return NULL;
923}
924EXPORT_SYMBOL_GPL(nfs4_decode_mp_ds_addr);
925
926void
927pnfs_layout_mark_request_commit(struct nfs_page *req,
928				struct pnfs_layout_segment *lseg,
929				struct nfs_commit_info *cinfo,
930				u32 ds_commit_idx)
931{
932	struct list_head *list;
933	struct pnfs_commit_bucket *buckets;
934
935	spin_lock(&cinfo->inode->i_lock);
936	buckets = cinfo->ds->buckets;
937	list = &buckets[ds_commit_idx].written;
938	if (list_empty(list)) {
939		if (!pnfs_is_valid_lseg(lseg)) {
940			spin_unlock(&cinfo->inode->i_lock);
941			cinfo->completion_ops->resched_write(cinfo, req);
942			return;
943		}
944		/* Non-empty buckets hold a reference on the lseg.  That ref
945		 * is normally transferred to the COMMIT call and released
946		 * there.  It could also be released if the last req is pulled
947		 * off due to a rewrite, in which case it will be done in
948		 * pnfs_common_clear_request_commit
949		 */
950		WARN_ON_ONCE(buckets[ds_commit_idx].wlseg != NULL);
951		buckets[ds_commit_idx].wlseg = pnfs_get_lseg(lseg);
952	}
953	set_bit(PG_COMMIT_TO_DS, &req->wb_flags);
954	cinfo->ds->nwritten++;
955
956	nfs_request_add_commit_list_locked(req, list, cinfo);
957	spin_unlock(&cinfo->inode->i_lock);
958	nfs_mark_page_unstable(req->wb_page, cinfo);
959}
960EXPORT_SYMBOL_GPL(pnfs_layout_mark_request_commit);
961
962int
963pnfs_nfs_generic_sync(struct inode *inode, bool datasync)
964{
965	int ret;
966
967	if (!pnfs_layoutcommit_outstanding(inode))
968		return 0;
969	ret = nfs_commit_inode(inode, FLUSH_SYNC);
970	if (ret < 0)
971		return ret;
972	if (datasync)
973		return 0;
974	return pnfs_layoutcommit_inode(inode, true);
975}
976EXPORT_SYMBOL_GPL(pnfs_nfs_generic_sync);
977