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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 "pnfs.h"
32
33#define NFSDBG_FACILITY NFSDBG_PNFS
34
35/*
36 * Device ID RCU cache. A device ID is unique per server and layout type.
37 */
38#define NFS4_DEVICE_ID_HASH_BITS 5
39#define NFS4_DEVICE_ID_HASH_SIZE (1 << NFS4_DEVICE_ID_HASH_BITS)
40#define NFS4_DEVICE_ID_HASH_MASK (NFS4_DEVICE_ID_HASH_SIZE - 1)
41
42static struct hlist_head nfs4_deviceid_cache[NFS4_DEVICE_ID_HASH_SIZE];
43static DEFINE_SPINLOCK(nfs4_deviceid_lock);
44
45void
46nfs4_print_deviceid(const struct nfs4_deviceid *id)
47{
48 u32 *p = (u32 *)id;
49
50 dprintk("%s: device id= [%x%x%x%x]\n", __func__,
51 p[0], p[1], p[2], p[3]);
52}
53EXPORT_SYMBOL_GPL(nfs4_print_deviceid);
54
55static inline u32
56nfs4_deviceid_hash(const struct nfs4_deviceid *id)
57{
58 unsigned char *cptr = (unsigned char *)id->data;
59 unsigned int nbytes = NFS4_DEVICEID4_SIZE;
60 u32 x = 0;
61
62 while (nbytes--) {
63 x *= 37;
64 x += *cptr++;
65 }
66 return x & NFS4_DEVICE_ID_HASH_MASK;
67}
68
69static struct nfs4_deviceid_node *
70_lookup_deviceid(const struct pnfs_layoutdriver_type *ld,
71 const struct nfs_client *clp, const struct nfs4_deviceid *id,
72 long hash)
73{
74 struct nfs4_deviceid_node *d;
75 struct hlist_node *n;
76
77 hlist_for_each_entry_rcu(d, n, &nfs4_deviceid_cache[hash], node)
78 if (d->ld == ld && d->nfs_client == clp &&
79 !memcmp(&d->deviceid, id, sizeof(*id))) {
80 if (atomic_read(&d->ref))
81 return d;
82 else
83 continue;
84 }
85 return NULL;
86}
87
88/*
89 * Lookup a deviceid in cache and get a reference count on it if found
90 *
91 * @clp nfs_client associated with deviceid
92 * @id deviceid to look up
93 */
94struct nfs4_deviceid_node *
95_find_get_deviceid(const struct pnfs_layoutdriver_type *ld,
96 const struct nfs_client *clp, const struct nfs4_deviceid *id,
97 long hash)
98{
99 struct nfs4_deviceid_node *d;
100
101 rcu_read_lock();
102 d = _lookup_deviceid(ld, clp, id, hash);
103 if (d != NULL)
104 atomic_inc(&d->ref);
105 rcu_read_unlock();
106 return d;
107}
108
109struct nfs4_deviceid_node *
110nfs4_find_get_deviceid(const struct pnfs_layoutdriver_type *ld,
111 const struct nfs_client *clp, const struct nfs4_deviceid *id)
112{
113 return _find_get_deviceid(ld, clp, id, nfs4_deviceid_hash(id));
114}
115EXPORT_SYMBOL_GPL(nfs4_find_get_deviceid);
116
117/*
118 * Remove a deviceid from cache
119 *
120 * @clp nfs_client associated with deviceid
121 * @id the deviceid to unhash
122 *
123 * @ret the unhashed node, if found and dereferenced to zero, NULL otherwise.
124 */
125void
126nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *ld,
127 const struct nfs_client *clp, const struct nfs4_deviceid *id)
128{
129 struct nfs4_deviceid_node *d;
130
131 spin_lock(&nfs4_deviceid_lock);
132 rcu_read_lock();
133 d = _lookup_deviceid(ld, clp, id, nfs4_deviceid_hash(id));
134 rcu_read_unlock();
135 if (!d) {
136 spin_unlock(&nfs4_deviceid_lock);
137 return;
138 }
139 hlist_del_init_rcu(&d->node);
140 spin_unlock(&nfs4_deviceid_lock);
141 synchronize_rcu();
142
143 /* balance the initial ref set in pnfs_insert_deviceid */
144 if (atomic_dec_and_test(&d->ref))
145 d->ld->free_deviceid_node(d);
146}
147EXPORT_SYMBOL_GPL(nfs4_delete_deviceid);
148
149void
150nfs4_init_deviceid_node(struct nfs4_deviceid_node *d,
151 const struct pnfs_layoutdriver_type *ld,
152 const struct nfs_client *nfs_client,
153 const struct nfs4_deviceid *id)
154{
155 INIT_HLIST_NODE(&d->node);
156 INIT_HLIST_NODE(&d->tmpnode);
157 d->ld = ld;
158 d->nfs_client = nfs_client;
159 d->flags = 0;
160 d->deviceid = *id;
161 atomic_set(&d->ref, 1);
162}
163EXPORT_SYMBOL_GPL(nfs4_init_deviceid_node);
164
165/*
166 * Uniquely initialize and insert a deviceid node into cache
167 *
168 * @new new deviceid node
169 * Note that the caller must set up the following members:
170 * new->ld
171 * new->nfs_client
172 * new->deviceid
173 *
174 * @ret the inserted node, if none found, otherwise, the found entry.
175 */
176struct nfs4_deviceid_node *
177nfs4_insert_deviceid_node(struct nfs4_deviceid_node *new)
178{
179 struct nfs4_deviceid_node *d;
180 long hash;
181
182 spin_lock(&nfs4_deviceid_lock);
183 hash = nfs4_deviceid_hash(&new->deviceid);
184 d = _find_get_deviceid(new->ld, new->nfs_client, &new->deviceid, hash);
185 if (d) {
186 spin_unlock(&nfs4_deviceid_lock);
187 return d;
188 }
189
190 hlist_add_head_rcu(&new->node, &nfs4_deviceid_cache[hash]);
191 spin_unlock(&nfs4_deviceid_lock);
192 atomic_inc(&new->ref);
193
194 return new;
195}
196EXPORT_SYMBOL_GPL(nfs4_insert_deviceid_node);
197
198/*
199 * Dereference a deviceid node and delete it when its reference count drops
200 * to zero.
201 *
202 * @d deviceid node to put
203 *
204 * return true iff the node was deleted
205 * Note that since the test for d->ref == 0 is sufficient to establish
206 * that the node is no longer hashed in the global device id cache.
207 */
208bool
209nfs4_put_deviceid_node(struct nfs4_deviceid_node *d)
210{
211 if (!atomic_dec_and_test(&d->ref))
212 return false;
213 d->ld->free_deviceid_node(d);
214 return true;
215}
216EXPORT_SYMBOL_GPL(nfs4_put_deviceid_node);
217
218static void
219_deviceid_purge_client(const struct nfs_client *clp, long hash)
220{
221 struct nfs4_deviceid_node *d;
222 struct hlist_node *n;
223 HLIST_HEAD(tmp);
224
225 spin_lock(&nfs4_deviceid_lock);
226 rcu_read_lock();
227 hlist_for_each_entry_rcu(d, n, &nfs4_deviceid_cache[hash], node)
228 if (d->nfs_client == clp && atomic_read(&d->ref)) {
229 hlist_del_init_rcu(&d->node);
230 hlist_add_head(&d->tmpnode, &tmp);
231 }
232 rcu_read_unlock();
233 spin_unlock(&nfs4_deviceid_lock);
234
235 if (hlist_empty(&tmp))
236 return;
237
238 synchronize_rcu();
239 while (!hlist_empty(&tmp)) {
240 d = hlist_entry(tmp.first, struct nfs4_deviceid_node, tmpnode);
241 hlist_del(&d->tmpnode);
242 if (atomic_dec_and_test(&d->ref))
243 d->ld->free_deviceid_node(d);
244 }
245}
246
247void
248nfs4_deviceid_purge_client(const struct nfs_client *clp)
249{
250 long h;
251
252 if (!(clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_MDS))
253 return;
254 for (h = 0; h < NFS4_DEVICE_ID_HASH_SIZE; h++)
255 _deviceid_purge_client(clp, h);
256}
257
258/*
259 * Stop use of all deviceids associated with an nfs_client
260 */
261void
262nfs4_deviceid_mark_client_invalid(struct nfs_client *clp)
263{
264 struct nfs4_deviceid_node *d;
265 struct hlist_node *n;
266 int i;
267
268 rcu_read_lock();
269 for (i = 0; i < NFS4_DEVICE_ID_HASH_SIZE; i ++){
270 hlist_for_each_entry_rcu(d, n, &nfs4_deviceid_cache[i], node)
271 if (d->nfs_client == clp)
272 set_bit(NFS_DEVICEID_INVALID, &d->flags);
273 }
274 rcu_read_unlock();
275}
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}