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v4.17
  1/*
  2 *  Device operations for the pnfs client.
  3 *
  4 *  Copyright (c) 2002
  5 *  The Regents of the University of Michigan
  6 *  All Rights Reserved
  7 *
  8 *  Dean Hildebrand <dhildebz@umich.edu>
  9 *  Garth Goodson   <Garth.Goodson@netapp.com>
 10 *
 11 *  Permission is granted to use, copy, create derivative works, and
 12 *  redistribute this software and such derivative works for any purpose,
 13 *  so long as the name of the University of Michigan is not used in
 14 *  any advertising or publicity pertaining to the use or distribution
 15 *  of this software without specific, written prior authorization. If
 16 *  the above copyright notice or any other identification of the
 17 *  University of Michigan is included in any copy of any portion of
 18 *  this software, then the disclaimer below must also be included.
 19 *
 20 *  This software is provided as is, without representation or warranty
 21 *  of any kind either express or implied, including without limitation
 22 *  the implied warranties of merchantability, fitness for a particular
 23 *  purpose, or noninfringement.  The Regents of the University of
 24 *  Michigan shall not be liable for any damages, including special,
 25 *  indirect, incidental, or consequential damages, with respect to any
 26 *  claim arising out of or in connection with the use of the software,
 27 *  even if it has been or is hereafter advised of the possibility of
 28 *  such damages.
 29 */
 30
 31#include <linux/export.h>
 32#include <linux/nfs_fs.h>
 33#include "nfs4session.h"
 34#include "internal.h"
 35#include "pnfs.h"
 36
 37#define NFSDBG_FACILITY		NFSDBG_PNFS
 38
 39/*
 40 * Device ID RCU cache. A device ID is unique per server and layout type.
 41 */
 42#define NFS4_DEVICE_ID_HASH_BITS	5
 43#define NFS4_DEVICE_ID_HASH_SIZE	(1 << NFS4_DEVICE_ID_HASH_BITS)
 44#define NFS4_DEVICE_ID_HASH_MASK	(NFS4_DEVICE_ID_HASH_SIZE - 1)
 45
 
 46
 47static struct hlist_head nfs4_deviceid_cache[NFS4_DEVICE_ID_HASH_SIZE];
 48static DEFINE_SPINLOCK(nfs4_deviceid_lock);
 49
 50#ifdef NFS_DEBUG
 51void
 52nfs4_print_deviceid(const struct nfs4_deviceid *id)
 53{
 54	u32 *p = (u32 *)id;
 55
 56	dprintk("%s: device id= [%x%x%x%x]\n", __func__,
 57		p[0], p[1], p[2], p[3]);
 58}
 59EXPORT_SYMBOL_GPL(nfs4_print_deviceid);
 60#endif
 61
 62static inline u32
 63nfs4_deviceid_hash(const struct nfs4_deviceid *id)
 64{
 65	unsigned char *cptr = (unsigned char *)id->data;
 66	unsigned int nbytes = NFS4_DEVICEID4_SIZE;
 67	u32 x = 0;
 68
 69	while (nbytes--) {
 70		x *= 37;
 71		x += *cptr++;
 72	}
 73	return x & NFS4_DEVICE_ID_HASH_MASK;
 74}
 75
 76static struct nfs4_deviceid_node *
 77_lookup_deviceid(const struct pnfs_layoutdriver_type *ld,
 78		 const struct nfs_client *clp, const struct nfs4_deviceid *id,
 79		 long hash)
 80{
 81	struct nfs4_deviceid_node *d;
 82
 83	hlist_for_each_entry_rcu(d, &nfs4_deviceid_cache[hash], node)
 84		if (d->ld == ld && d->nfs_client == clp &&
 85		    !memcmp(&d->deviceid, id, sizeof(*id))) {
 86			if (atomic_read(&d->ref))
 87				return d;
 88			else
 89				continue;
 90		}
 91	return NULL;
 92}
 93
 94static struct nfs4_deviceid_node *
 95nfs4_get_device_info(struct nfs_server *server,
 96		const struct nfs4_deviceid *dev_id,
 97		struct rpc_cred *cred, gfp_t gfp_flags)
 98{
 99	struct nfs4_deviceid_node *d = NULL;
100	struct pnfs_device *pdev = NULL;
101	struct page **pages = NULL;
102	u32 max_resp_sz;
103	int max_pages;
104	int rc, i;
105
106	/*
107	 * Use the session max response size as the basis for setting
108	 * GETDEVICEINFO's maxcount
109	 */
110	max_resp_sz = server->nfs_client->cl_session->fc_attrs.max_resp_sz;
111	if (server->pnfs_curr_ld->max_deviceinfo_size &&
112	    server->pnfs_curr_ld->max_deviceinfo_size < max_resp_sz)
113		max_resp_sz = server->pnfs_curr_ld->max_deviceinfo_size;
114	max_pages = nfs_page_array_len(0, max_resp_sz);
115	dprintk("%s: server %p max_resp_sz %u max_pages %d\n",
116		__func__, server, max_resp_sz, max_pages);
117
118	pdev = kzalloc(sizeof(*pdev), gfp_flags);
119	if (!pdev)
120		return NULL;
121
122	pages = kcalloc(max_pages, sizeof(struct page *), gfp_flags);
123	if (!pages)
124		goto out_free_pdev;
125
126	for (i = 0; i < max_pages; i++) {
127		pages[i] = alloc_page(gfp_flags);
128		if (!pages[i])
129			goto out_free_pages;
130	}
131
132	memcpy(&pdev->dev_id, dev_id, sizeof(*dev_id));
133	pdev->layout_type = server->pnfs_curr_ld->id;
134	pdev->pages = pages;
135	pdev->pgbase = 0;
136	pdev->pglen = max_resp_sz;
137	pdev->mincount = 0;
138	pdev->maxcount = max_resp_sz - nfs41_maxgetdevinfo_overhead;
139
140	rc = nfs4_proc_getdeviceinfo(server, pdev, cred);
141	dprintk("%s getdevice info returns %d\n", __func__, rc);
142	if (rc)
143		goto out_free_pages;
144
145	/*
146	 * Found new device, need to decode it and then add it to the
147	 * list of known devices for this mountpoint.
148	 */
149	d = server->pnfs_curr_ld->alloc_deviceid_node(server, pdev,
150			gfp_flags);
151	if (d && pdev->nocache)
152		set_bit(NFS_DEVICEID_NOCACHE, &d->flags);
153
154out_free_pages:
155	for (i = 0; i < max_pages; i++)
156		__free_page(pages[i]);
157	kfree(pages);
158out_free_pdev:
159	kfree(pdev);
160	dprintk("<-- %s d %p\n", __func__, d);
161	return d;
162}
163
164/*
165 * Lookup a deviceid in cache and get a reference count on it if found
166 *
167 * @clp nfs_client associated with deviceid
168 * @id deviceid to look up
169 */
170static struct nfs4_deviceid_node *
171__nfs4_find_get_deviceid(struct nfs_server *server,
172		const struct nfs4_deviceid *id, long hash)
173{
174	struct nfs4_deviceid_node *d;
175
176	rcu_read_lock();
177	d = _lookup_deviceid(server->pnfs_curr_ld, server->nfs_client, id,
178			hash);
179	if (d != NULL && !atomic_inc_not_zero(&d->ref))
180		d = NULL;
181	rcu_read_unlock();
182	return d;
183}
184
185struct nfs4_deviceid_node *
186nfs4_find_get_deviceid(struct nfs_server *server,
187		const struct nfs4_deviceid *id, struct rpc_cred *cred,
188		gfp_t gfp_mask)
189{
190	long hash = nfs4_deviceid_hash(id);
191	struct nfs4_deviceid_node *d, *new;
192
193	d = __nfs4_find_get_deviceid(server, id, hash);
194	if (d)
195		return d;
196
197	new = nfs4_get_device_info(server, id, cred, gfp_mask);
198	if (!new)
199		return new;
200
201	spin_lock(&nfs4_deviceid_lock);
202	d = __nfs4_find_get_deviceid(server, id, hash);
203	if (d) {
204		spin_unlock(&nfs4_deviceid_lock);
205		server->pnfs_curr_ld->free_deviceid_node(new);
206		return d;
207	}
208	hlist_add_head_rcu(&new->node, &nfs4_deviceid_cache[hash]);
209	atomic_inc(&new->ref);
210	spin_unlock(&nfs4_deviceid_lock);
211
212	return new;
213}
214EXPORT_SYMBOL_GPL(nfs4_find_get_deviceid);
215
216/*
217 * Remove a deviceid from cache
218 *
219 * @clp nfs_client associated with deviceid
220 * @id the deviceid to unhash
221 *
222 * @ret the unhashed node, if found and dereferenced to zero, NULL otherwise.
223 */
224void
225nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *ld,
226			 const struct nfs_client *clp, const struct nfs4_deviceid *id)
227{
228	struct nfs4_deviceid_node *d;
229
230	spin_lock(&nfs4_deviceid_lock);
231	rcu_read_lock();
232	d = _lookup_deviceid(ld, clp, id, nfs4_deviceid_hash(id));
233	rcu_read_unlock();
234	if (!d) {
235		spin_unlock(&nfs4_deviceid_lock);
236		return;
237	}
238	hlist_del_init_rcu(&d->node);
239	clear_bit(NFS_DEVICEID_NOCACHE, &d->flags);
240	spin_unlock(&nfs4_deviceid_lock);
241
242	/* balance the initial ref set in pnfs_insert_deviceid */
243	nfs4_put_deviceid_node(d);
244}
245EXPORT_SYMBOL_GPL(nfs4_delete_deviceid);
246
247void
248nfs4_init_deviceid_node(struct nfs4_deviceid_node *d, struct nfs_server *server,
249			const struct nfs4_deviceid *id)
250{
251	INIT_HLIST_NODE(&d->node);
252	INIT_HLIST_NODE(&d->tmpnode);
253	d->ld = server->pnfs_curr_ld;
254	d->nfs_client = server->nfs_client;
255	d->flags = 0;
256	d->deviceid = *id;
257	atomic_set(&d->ref, 1);
258}
259EXPORT_SYMBOL_GPL(nfs4_init_deviceid_node);
260
261/*
262 * Dereference a deviceid node and delete it when its reference count drops
263 * to zero.
264 *
265 * @d deviceid node to put
266 *
267 * return true iff the node was deleted
268 * Note that since the test for d->ref == 0 is sufficient to establish
269 * that the node is no longer hashed in the global device id cache.
270 */
271bool
272nfs4_put_deviceid_node(struct nfs4_deviceid_node *d)
273{
274	if (test_bit(NFS_DEVICEID_NOCACHE, &d->flags)) {
275		if (atomic_add_unless(&d->ref, -1, 2))
276			return false;
277		nfs4_delete_deviceid(d->ld, d->nfs_client, &d->deviceid);
278	}
279	if (!atomic_dec_and_test(&d->ref))
280		return false;
281	d->ld->free_deviceid_node(d);
282	return true;
283}
284EXPORT_SYMBOL_GPL(nfs4_put_deviceid_node);
285
286void
287nfs4_mark_deviceid_unavailable(struct nfs4_deviceid_node *node)
288{
289	node->timestamp_unavailable = jiffies;
290	set_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags);
291}
292EXPORT_SYMBOL_GPL(nfs4_mark_deviceid_unavailable);
293
294bool
295nfs4_test_deviceid_unavailable(struct nfs4_deviceid_node *node)
296{
297	if (test_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags)) {
298		unsigned long start, end;
299
300		end = jiffies;
301		start = end - PNFS_DEVICE_RETRY_TIMEOUT;
302		if (time_in_range(node->timestamp_unavailable, start, end))
303			return true;
304		clear_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags);
305	}
306	return false;
307}
308EXPORT_SYMBOL_GPL(nfs4_test_deviceid_unavailable);
309
310static void
311_deviceid_purge_client(const struct nfs_client *clp, long hash)
312{
313	struct nfs4_deviceid_node *d;
314	HLIST_HEAD(tmp);
315
316	spin_lock(&nfs4_deviceid_lock);
317	rcu_read_lock();
318	hlist_for_each_entry_rcu(d, &nfs4_deviceid_cache[hash], node)
319		if (d->nfs_client == clp && atomic_read(&d->ref)) {
320			hlist_del_init_rcu(&d->node);
321			hlist_add_head(&d->tmpnode, &tmp);
322			clear_bit(NFS_DEVICEID_NOCACHE, &d->flags);
323		}
324	rcu_read_unlock();
325	spin_unlock(&nfs4_deviceid_lock);
326
327	if (hlist_empty(&tmp))
328		return;
329
330	while (!hlist_empty(&tmp)) {
331		d = hlist_entry(tmp.first, struct nfs4_deviceid_node, tmpnode);
332		hlist_del(&d->tmpnode);
333		nfs4_put_deviceid_node(d);
334	}
335}
336
337void
338nfs4_deviceid_purge_client(const struct nfs_client *clp)
339{
340	long h;
341
342	if (!(clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_MDS))
343		return;
344	for (h = 0; h < NFS4_DEVICE_ID_HASH_SIZE; h++)
345		_deviceid_purge_client(clp, h);
346}
347
348/*
349 * Stop use of all deviceids associated with an nfs_client
350 */
351void
352nfs4_deviceid_mark_client_invalid(struct nfs_client *clp)
353{
354	struct nfs4_deviceid_node *d;
355	int i;
356
357	rcu_read_lock();
358	for (i = 0; i < NFS4_DEVICE_ID_HASH_SIZE; i ++){
359		hlist_for_each_entry_rcu(d, &nfs4_deviceid_cache[i], node)
360			if (d->nfs_client == clp)
361				set_bit(NFS_DEVICEID_INVALID, &d->flags);
362	}
363	rcu_read_unlock();
364}
v4.10.11
  1/*
  2 *  Device operations for the pnfs client.
  3 *
  4 *  Copyright (c) 2002
  5 *  The Regents of the University of Michigan
  6 *  All Rights Reserved
  7 *
  8 *  Dean Hildebrand <dhildebz@umich.edu>
  9 *  Garth Goodson   <Garth.Goodson@netapp.com>
 10 *
 11 *  Permission is granted to use, copy, create derivative works, and
 12 *  redistribute this software and such derivative works for any purpose,
 13 *  so long as the name of the University of Michigan is not used in
 14 *  any advertising or publicity pertaining to the use or distribution
 15 *  of this software without specific, written prior authorization. If
 16 *  the above copyright notice or any other identification of the
 17 *  University of Michigan is included in any copy of any portion of
 18 *  this software, then the disclaimer below must also be included.
 19 *
 20 *  This software is provided as is, without representation or warranty
 21 *  of any kind either express or implied, including without limitation
 22 *  the implied warranties of merchantability, fitness for a particular
 23 *  purpose, or noninfringement.  The Regents of the University of
 24 *  Michigan shall not be liable for any damages, including special,
 25 *  indirect, incidental, or consequential damages, with respect to any
 26 *  claim arising out of or in connection with the use of the software,
 27 *  even if it has been or is hereafter advised of the possibility of
 28 *  such damages.
 29 */
 30
 31#include <linux/export.h>
 32#include <linux/nfs_fs.h>
 33#include "nfs4session.h"
 34#include "internal.h"
 35#include "pnfs.h"
 36
 37#define NFSDBG_FACILITY		NFSDBG_PNFS
 38
 39/*
 40 * Device ID RCU cache. A device ID is unique per server and layout type.
 41 */
 42#define NFS4_DEVICE_ID_HASH_BITS	5
 43#define NFS4_DEVICE_ID_HASH_SIZE	(1 << NFS4_DEVICE_ID_HASH_BITS)
 44#define NFS4_DEVICE_ID_HASH_MASK	(NFS4_DEVICE_ID_HASH_SIZE - 1)
 45
 46#define PNFS_DEVICE_RETRY_TIMEOUT (120*HZ)
 47
 48static struct hlist_head nfs4_deviceid_cache[NFS4_DEVICE_ID_HASH_SIZE];
 49static DEFINE_SPINLOCK(nfs4_deviceid_lock);
 50
 51#ifdef NFS_DEBUG
 52void
 53nfs4_print_deviceid(const struct nfs4_deviceid *id)
 54{
 55	u32 *p = (u32 *)id;
 56
 57	dprintk("%s: device id= [%x%x%x%x]\n", __func__,
 58		p[0], p[1], p[2], p[3]);
 59}
 60EXPORT_SYMBOL_GPL(nfs4_print_deviceid);
 61#endif
 62
 63static inline u32
 64nfs4_deviceid_hash(const struct nfs4_deviceid *id)
 65{
 66	unsigned char *cptr = (unsigned char *)id->data;
 67	unsigned int nbytes = NFS4_DEVICEID4_SIZE;
 68	u32 x = 0;
 69
 70	while (nbytes--) {
 71		x *= 37;
 72		x += *cptr++;
 73	}
 74	return x & NFS4_DEVICE_ID_HASH_MASK;
 75}
 76
 77static struct nfs4_deviceid_node *
 78_lookup_deviceid(const struct pnfs_layoutdriver_type *ld,
 79		 const struct nfs_client *clp, const struct nfs4_deviceid *id,
 80		 long hash)
 81{
 82	struct nfs4_deviceid_node *d;
 83
 84	hlist_for_each_entry_rcu(d, &nfs4_deviceid_cache[hash], node)
 85		if (d->ld == ld && d->nfs_client == clp &&
 86		    !memcmp(&d->deviceid, id, sizeof(*id))) {
 87			if (atomic_read(&d->ref))
 88				return d;
 89			else
 90				continue;
 91		}
 92	return NULL;
 93}
 94
 95static struct nfs4_deviceid_node *
 96nfs4_get_device_info(struct nfs_server *server,
 97		const struct nfs4_deviceid *dev_id,
 98		struct rpc_cred *cred, gfp_t gfp_flags)
 99{
100	struct nfs4_deviceid_node *d = NULL;
101	struct pnfs_device *pdev = NULL;
102	struct page **pages = NULL;
103	u32 max_resp_sz;
104	int max_pages;
105	int rc, i;
106
107	/*
108	 * Use the session max response size as the basis for setting
109	 * GETDEVICEINFO's maxcount
110	 */
111	max_resp_sz = server->nfs_client->cl_session->fc_attrs.max_resp_sz;
112	if (server->pnfs_curr_ld->max_deviceinfo_size &&
113	    server->pnfs_curr_ld->max_deviceinfo_size < max_resp_sz)
114		max_resp_sz = server->pnfs_curr_ld->max_deviceinfo_size;
115	max_pages = nfs_page_array_len(0, max_resp_sz);
116	dprintk("%s: server %p max_resp_sz %u max_pages %d\n",
117		__func__, server, max_resp_sz, max_pages);
118
119	pdev = kzalloc(sizeof(*pdev), gfp_flags);
120	if (!pdev)
121		return NULL;
122
123	pages = kcalloc(max_pages, sizeof(struct page *), gfp_flags);
124	if (!pages)
125		goto out_free_pdev;
126
127	for (i = 0; i < max_pages; i++) {
128		pages[i] = alloc_page(gfp_flags);
129		if (!pages[i])
130			goto out_free_pages;
131	}
132
133	memcpy(&pdev->dev_id, dev_id, sizeof(*dev_id));
134	pdev->layout_type = server->pnfs_curr_ld->id;
135	pdev->pages = pages;
136	pdev->pgbase = 0;
137	pdev->pglen = max_resp_sz;
138	pdev->mincount = 0;
139	pdev->maxcount = max_resp_sz - nfs41_maxgetdevinfo_overhead;
140
141	rc = nfs4_proc_getdeviceinfo(server, pdev, cred);
142	dprintk("%s getdevice info returns %d\n", __func__, rc);
143	if (rc)
144		goto out_free_pages;
145
146	/*
147	 * Found new device, need to decode it and then add it to the
148	 * list of known devices for this mountpoint.
149	 */
150	d = server->pnfs_curr_ld->alloc_deviceid_node(server, pdev,
151			gfp_flags);
152	if (d && pdev->nocache)
153		set_bit(NFS_DEVICEID_NOCACHE, &d->flags);
154
155out_free_pages:
156	for (i = 0; i < max_pages; i++)
157		__free_page(pages[i]);
158	kfree(pages);
159out_free_pdev:
160	kfree(pdev);
161	dprintk("<-- %s d %p\n", __func__, d);
162	return d;
163}
164
165/*
166 * Lookup a deviceid in cache and get a reference count on it if found
167 *
168 * @clp nfs_client associated with deviceid
169 * @id deviceid to look up
170 */
171static struct nfs4_deviceid_node *
172__nfs4_find_get_deviceid(struct nfs_server *server,
173		const struct nfs4_deviceid *id, long hash)
174{
175	struct nfs4_deviceid_node *d;
176
177	rcu_read_lock();
178	d = _lookup_deviceid(server->pnfs_curr_ld, server->nfs_client, id,
179			hash);
180	if (d != NULL && !atomic_inc_not_zero(&d->ref))
181		d = NULL;
182	rcu_read_unlock();
183	return d;
184}
185
186struct nfs4_deviceid_node *
187nfs4_find_get_deviceid(struct nfs_server *server,
188		const struct nfs4_deviceid *id, struct rpc_cred *cred,
189		gfp_t gfp_mask)
190{
191	long hash = nfs4_deviceid_hash(id);
192	struct nfs4_deviceid_node *d, *new;
193
194	d = __nfs4_find_get_deviceid(server, id, hash);
195	if (d)
196		return d;
197
198	new = nfs4_get_device_info(server, id, cred, gfp_mask);
199	if (!new)
200		return new;
201
202	spin_lock(&nfs4_deviceid_lock);
203	d = __nfs4_find_get_deviceid(server, id, hash);
204	if (d) {
205		spin_unlock(&nfs4_deviceid_lock);
206		server->pnfs_curr_ld->free_deviceid_node(new);
207		return d;
208	}
209	hlist_add_head_rcu(&new->node, &nfs4_deviceid_cache[hash]);
210	atomic_inc(&new->ref);
211	spin_unlock(&nfs4_deviceid_lock);
212
213	return new;
214}
215EXPORT_SYMBOL_GPL(nfs4_find_get_deviceid);
216
217/*
218 * Remove a deviceid from cache
219 *
220 * @clp nfs_client associated with deviceid
221 * @id the deviceid to unhash
222 *
223 * @ret the unhashed node, if found and dereferenced to zero, NULL otherwise.
224 */
225void
226nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *ld,
227			 const struct nfs_client *clp, const struct nfs4_deviceid *id)
228{
229	struct nfs4_deviceid_node *d;
230
231	spin_lock(&nfs4_deviceid_lock);
232	rcu_read_lock();
233	d = _lookup_deviceid(ld, clp, id, nfs4_deviceid_hash(id));
234	rcu_read_unlock();
235	if (!d) {
236		spin_unlock(&nfs4_deviceid_lock);
237		return;
238	}
239	hlist_del_init_rcu(&d->node);
240	clear_bit(NFS_DEVICEID_NOCACHE, &d->flags);
241	spin_unlock(&nfs4_deviceid_lock);
242
243	/* balance the initial ref set in pnfs_insert_deviceid */
244	nfs4_put_deviceid_node(d);
245}
246EXPORT_SYMBOL_GPL(nfs4_delete_deviceid);
247
248void
249nfs4_init_deviceid_node(struct nfs4_deviceid_node *d, struct nfs_server *server,
250			const struct nfs4_deviceid *id)
251{
252	INIT_HLIST_NODE(&d->node);
253	INIT_HLIST_NODE(&d->tmpnode);
254	d->ld = server->pnfs_curr_ld;
255	d->nfs_client = server->nfs_client;
256	d->flags = 0;
257	d->deviceid = *id;
258	atomic_set(&d->ref, 1);
259}
260EXPORT_SYMBOL_GPL(nfs4_init_deviceid_node);
261
262/*
263 * Dereference a deviceid node and delete it when its reference count drops
264 * to zero.
265 *
266 * @d deviceid node to put
267 *
268 * return true iff the node was deleted
269 * Note that since the test for d->ref == 0 is sufficient to establish
270 * that the node is no longer hashed in the global device id cache.
271 */
272bool
273nfs4_put_deviceid_node(struct nfs4_deviceid_node *d)
274{
275	if (test_bit(NFS_DEVICEID_NOCACHE, &d->flags)) {
276		if (atomic_add_unless(&d->ref, -1, 2))
277			return false;
278		nfs4_delete_deviceid(d->ld, d->nfs_client, &d->deviceid);
279	}
280	if (!atomic_dec_and_test(&d->ref))
281		return false;
282	d->ld->free_deviceid_node(d);
283	return true;
284}
285EXPORT_SYMBOL_GPL(nfs4_put_deviceid_node);
286
287void
288nfs4_mark_deviceid_unavailable(struct nfs4_deviceid_node *node)
289{
290	node->timestamp_unavailable = jiffies;
291	set_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags);
292}
293EXPORT_SYMBOL_GPL(nfs4_mark_deviceid_unavailable);
294
295bool
296nfs4_test_deviceid_unavailable(struct nfs4_deviceid_node *node)
297{
298	if (test_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags)) {
299		unsigned long start, end;
300
301		end = jiffies;
302		start = end - PNFS_DEVICE_RETRY_TIMEOUT;
303		if (time_in_range(node->timestamp_unavailable, start, end))
304			return true;
305		clear_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags);
306	}
307	return false;
308}
309EXPORT_SYMBOL_GPL(nfs4_test_deviceid_unavailable);
310
311static void
312_deviceid_purge_client(const struct nfs_client *clp, long hash)
313{
314	struct nfs4_deviceid_node *d;
315	HLIST_HEAD(tmp);
316
317	spin_lock(&nfs4_deviceid_lock);
318	rcu_read_lock();
319	hlist_for_each_entry_rcu(d, &nfs4_deviceid_cache[hash], node)
320		if (d->nfs_client == clp && atomic_read(&d->ref)) {
321			hlist_del_init_rcu(&d->node);
322			hlist_add_head(&d->tmpnode, &tmp);
323			clear_bit(NFS_DEVICEID_NOCACHE, &d->flags);
324		}
325	rcu_read_unlock();
326	spin_unlock(&nfs4_deviceid_lock);
327
328	if (hlist_empty(&tmp))
329		return;
330
331	while (!hlist_empty(&tmp)) {
332		d = hlist_entry(tmp.first, struct nfs4_deviceid_node, tmpnode);
333		hlist_del(&d->tmpnode);
334		nfs4_put_deviceid_node(d);
335	}
336}
337
338void
339nfs4_deviceid_purge_client(const struct nfs_client *clp)
340{
341	long h;
342
343	if (!(clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_MDS))
344		return;
345	for (h = 0; h < NFS4_DEVICE_ID_HASH_SIZE; h++)
346		_deviceid_purge_client(clp, h);
347}
348
349/*
350 * Stop use of all deviceids associated with an nfs_client
351 */
352void
353nfs4_deviceid_mark_client_invalid(struct nfs_client *clp)
354{
355	struct nfs4_deviceid_node *d;
356	int i;
357
358	rcu_read_lock();
359	for (i = 0; i < NFS4_DEVICE_ID_HASH_SIZE; i ++){
360		hlist_for_each_entry_rcu(d, &nfs4_deviceid_cache[i], node)
361			if (d->nfs_client == clp)
362				set_bit(NFS_DEVICEID_INVALID, &d->flags);
363	}
364	rcu_read_unlock();
365}