Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/fs/nfs/delegation.c | |
3 | * | |
4 | * Copyright (C) 2004 Trond Myklebust | |
5 | * | |
6 | * NFS file delegation management | |
7 | * | |
8 | */ | |
9 | #include <linux/config.h> | |
10 | #include <linux/completion.h> | |
11 | #include <linux/module.h> | |
12 | #include <linux/sched.h> | |
13 | #include <linux/spinlock.h> | |
14 | ||
15 | #include <linux/nfs4.h> | |
16 | #include <linux/nfs_fs.h> | |
17 | #include <linux/nfs_xdr.h> | |
18 | ||
4ce79717 | 19 | #include "nfs4_fs.h" |
1da177e4 LT |
20 | #include "delegation.h" |
21 | ||
22 | static struct nfs_delegation *nfs_alloc_delegation(void) | |
23 | { | |
24 | return (struct nfs_delegation *)kmalloc(sizeof(struct nfs_delegation), GFP_KERNEL); | |
25 | } | |
26 | ||
27 | static void nfs_free_delegation(struct nfs_delegation *delegation) | |
28 | { | |
29 | if (delegation->cred) | |
30 | put_rpccred(delegation->cred); | |
31 | kfree(delegation); | |
32 | } | |
33 | ||
888e694c TM |
34 | static int nfs_delegation_claim_locks(struct nfs_open_context *ctx, struct nfs4_state *state) |
35 | { | |
36 | struct inode *inode = state->inode; | |
37 | struct file_lock *fl; | |
38 | int status; | |
39 | ||
40 | for (fl = inode->i_flock; fl != 0; fl = fl->fl_next) { | |
41 | if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK))) | |
42 | continue; | |
43 | if ((struct nfs_open_context *)fl->fl_file->private_data != ctx) | |
44 | continue; | |
45 | status = nfs4_lock_delegation_recall(state, fl); | |
46 | if (status >= 0) | |
47 | continue; | |
48 | switch (status) { | |
49 | default: | |
50 | printk(KERN_ERR "%s: unhandled error %d.\n", | |
51 | __FUNCTION__, status); | |
52 | case -NFS4ERR_EXPIRED: | |
53 | /* kill_proc(fl->fl_pid, SIGLOST, 1); */ | |
54 | case -NFS4ERR_STALE_CLIENTID: | |
55 | nfs4_schedule_state_recovery(NFS_SERVER(inode)->nfs4_state); | |
56 | goto out_err; | |
57 | } | |
58 | } | |
59 | return 0; | |
60 | out_err: | |
61 | return status; | |
62 | } | |
63 | ||
1da177e4 LT |
64 | static void nfs_delegation_claim_opens(struct inode *inode) |
65 | { | |
66 | struct nfs_inode *nfsi = NFS_I(inode); | |
67 | struct nfs_open_context *ctx; | |
68 | struct nfs4_state *state; | |
888e694c | 69 | int err; |
1da177e4 LT |
70 | |
71 | again: | |
72 | spin_lock(&inode->i_lock); | |
73 | list_for_each_entry(ctx, &nfsi->open_files, list) { | |
74 | state = ctx->state; | |
75 | if (state == NULL) | |
76 | continue; | |
77 | if (!test_bit(NFS_DELEGATED_STATE, &state->flags)) | |
78 | continue; | |
79 | get_nfs_open_context(ctx); | |
80 | spin_unlock(&inode->i_lock); | |
888e694c TM |
81 | err = nfs4_open_delegation_recall(ctx->dentry, state); |
82 | if (err >= 0) | |
83 | err = nfs_delegation_claim_locks(ctx, state); | |
1da177e4 | 84 | put_nfs_open_context(ctx); |
888e694c TM |
85 | if (err != 0) |
86 | return; | |
1da177e4 LT |
87 | goto again; |
88 | } | |
89 | spin_unlock(&inode->i_lock); | |
90 | } | |
91 | ||
92 | /* | |
93 | * Set up a delegation on an inode | |
94 | */ | |
95 | void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res) | |
96 | { | |
97 | struct nfs_delegation *delegation = NFS_I(inode)->delegation; | |
98 | ||
99 | if (delegation == NULL) | |
100 | return; | |
101 | memcpy(delegation->stateid.data, res->delegation.data, | |
102 | sizeof(delegation->stateid.data)); | |
103 | delegation->type = res->delegation_type; | |
104 | delegation->maxsize = res->maxsize; | |
105 | put_rpccred(cred); | |
106 | delegation->cred = get_rpccred(cred); | |
107 | delegation->flags &= ~NFS_DELEGATION_NEED_RECLAIM; | |
108 | NFS_I(inode)->delegation_state = delegation->type; | |
109 | smp_wmb(); | |
110 | } | |
111 | ||
112 | /* | |
113 | * Set up a delegation on an inode | |
114 | */ | |
115 | int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res) | |
116 | { | |
117 | struct nfs4_client *clp = NFS_SERVER(inode)->nfs4_state; | |
118 | struct nfs_inode *nfsi = NFS_I(inode); | |
119 | struct nfs_delegation *delegation; | |
120 | int status = 0; | |
121 | ||
b3c52da3 TM |
122 | /* Ensure we first revalidate the attributes and page cache! */ |
123 | if ((nfsi->cache_validity & (NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_ATTR))) | |
124 | __nfs_revalidate_inode(NFS_SERVER(inode), inode); | |
125 | ||
1da177e4 LT |
126 | delegation = nfs_alloc_delegation(); |
127 | if (delegation == NULL) | |
128 | return -ENOMEM; | |
129 | memcpy(delegation->stateid.data, res->delegation.data, | |
130 | sizeof(delegation->stateid.data)); | |
131 | delegation->type = res->delegation_type; | |
132 | delegation->maxsize = res->maxsize; | |
133 | delegation->cred = get_rpccred(cred); | |
134 | delegation->inode = inode; | |
135 | ||
136 | spin_lock(&clp->cl_lock); | |
137 | if (nfsi->delegation == NULL) { | |
138 | list_add(&delegation->super_list, &clp->cl_delegations); | |
139 | nfsi->delegation = delegation; | |
140 | nfsi->delegation_state = delegation->type; | |
141 | delegation = NULL; | |
142 | } else { | |
143 | if (memcmp(&delegation->stateid, &nfsi->delegation->stateid, | |
144 | sizeof(delegation->stateid)) != 0 || | |
145 | delegation->type != nfsi->delegation->type) { | |
146 | printk("%s: server %u.%u.%u.%u, handed out a duplicate delegation!\n", | |
147 | __FUNCTION__, NIPQUAD(clp->cl_addr)); | |
148 | status = -EIO; | |
149 | } | |
150 | } | |
151 | spin_unlock(&clp->cl_lock); | |
f99d49ad | 152 | kfree(delegation); |
1da177e4 LT |
153 | return status; |
154 | } | |
155 | ||
156 | static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation) | |
157 | { | |
158 | int res = 0; | |
159 | ||
160 | __nfs_revalidate_inode(NFS_SERVER(inode), inode); | |
161 | ||
162 | res = nfs4_proc_delegreturn(inode, delegation->cred, &delegation->stateid); | |
163 | nfs_free_delegation(delegation); | |
164 | return res; | |
165 | } | |
166 | ||
167 | /* Sync all data to disk upon delegation return */ | |
168 | static void nfs_msync_inode(struct inode *inode) | |
169 | { | |
170 | filemap_fdatawrite(inode->i_mapping); | |
171 | nfs_wb_all(inode); | |
172 | filemap_fdatawait(inode->i_mapping); | |
173 | } | |
174 | ||
175 | /* | |
176 | * Basic procedure for returning a delegation to the server | |
177 | */ | |
cae7a073 | 178 | int __nfs_inode_return_delegation(struct inode *inode) |
1da177e4 LT |
179 | { |
180 | struct nfs4_client *clp = NFS_SERVER(inode)->nfs4_state; | |
181 | struct nfs_inode *nfsi = NFS_I(inode); | |
182 | struct nfs_delegation *delegation; | |
183 | int res = 0; | |
184 | ||
185 | nfs_msync_inode(inode); | |
186 | down_read(&clp->cl_sem); | |
187 | /* Guard against new delegated open calls */ | |
188 | down_write(&nfsi->rwsem); | |
189 | spin_lock(&clp->cl_lock); | |
190 | delegation = nfsi->delegation; | |
191 | if (delegation != NULL) { | |
192 | list_del_init(&delegation->super_list); | |
193 | nfsi->delegation = NULL; | |
194 | nfsi->delegation_state = 0; | |
195 | } | |
196 | spin_unlock(&clp->cl_lock); | |
197 | nfs_delegation_claim_opens(inode); | |
198 | up_write(&nfsi->rwsem); | |
199 | up_read(&clp->cl_sem); | |
200 | nfs_msync_inode(inode); | |
201 | ||
202 | if (delegation != NULL) | |
203 | res = nfs_do_return_delegation(inode, delegation); | |
204 | return res; | |
205 | } | |
206 | ||
207 | /* | |
208 | * Return all delegations associated to a super block | |
209 | */ | |
210 | void nfs_return_all_delegations(struct super_block *sb) | |
211 | { | |
212 | struct nfs4_client *clp = NFS_SB(sb)->nfs4_state; | |
213 | struct nfs_delegation *delegation; | |
214 | struct inode *inode; | |
215 | ||
216 | if (clp == NULL) | |
217 | return; | |
218 | restart: | |
219 | spin_lock(&clp->cl_lock); | |
220 | list_for_each_entry(delegation, &clp->cl_delegations, super_list) { | |
221 | if (delegation->inode->i_sb != sb) | |
222 | continue; | |
223 | inode = igrab(delegation->inode); | |
224 | if (inode == NULL) | |
225 | continue; | |
226 | spin_unlock(&clp->cl_lock); | |
227 | nfs_inode_return_delegation(inode); | |
228 | iput(inode); | |
229 | goto restart; | |
230 | } | |
231 | spin_unlock(&clp->cl_lock); | |
232 | } | |
233 | ||
234 | /* | |
235 | * Return all delegations following an NFS4ERR_CB_PATH_DOWN error. | |
236 | */ | |
237 | void nfs_handle_cb_pathdown(struct nfs4_client *clp) | |
238 | { | |
239 | struct nfs_delegation *delegation; | |
240 | struct inode *inode; | |
241 | ||
242 | if (clp == NULL) | |
243 | return; | |
244 | restart: | |
245 | spin_lock(&clp->cl_lock); | |
246 | list_for_each_entry(delegation, &clp->cl_delegations, super_list) { | |
247 | inode = igrab(delegation->inode); | |
248 | if (inode == NULL) | |
249 | continue; | |
250 | spin_unlock(&clp->cl_lock); | |
251 | nfs_inode_return_delegation(inode); | |
252 | iput(inode); | |
253 | goto restart; | |
254 | } | |
255 | spin_unlock(&clp->cl_lock); | |
256 | } | |
257 | ||
258 | struct recall_threadargs { | |
259 | struct inode *inode; | |
260 | struct nfs4_client *clp; | |
261 | const nfs4_stateid *stateid; | |
262 | ||
263 | struct completion started; | |
264 | int result; | |
265 | }; | |
266 | ||
267 | static int recall_thread(void *data) | |
268 | { | |
269 | struct recall_threadargs *args = (struct recall_threadargs *)data; | |
270 | struct inode *inode = igrab(args->inode); | |
271 | struct nfs4_client *clp = NFS_SERVER(inode)->nfs4_state; | |
272 | struct nfs_inode *nfsi = NFS_I(inode); | |
273 | struct nfs_delegation *delegation; | |
274 | ||
275 | daemonize("nfsv4-delegreturn"); | |
276 | ||
277 | nfs_msync_inode(inode); | |
278 | down_read(&clp->cl_sem); | |
279 | down_write(&nfsi->rwsem); | |
280 | spin_lock(&clp->cl_lock); | |
281 | delegation = nfsi->delegation; | |
282 | if (delegation != NULL && memcmp(delegation->stateid.data, | |
283 | args->stateid->data, | |
284 | sizeof(delegation->stateid.data)) == 0) { | |
285 | list_del_init(&delegation->super_list); | |
286 | nfsi->delegation = NULL; | |
287 | nfsi->delegation_state = 0; | |
288 | args->result = 0; | |
289 | } else { | |
290 | delegation = NULL; | |
291 | args->result = -ENOENT; | |
292 | } | |
293 | spin_unlock(&clp->cl_lock); | |
294 | complete(&args->started); | |
295 | nfs_delegation_claim_opens(inode); | |
296 | up_write(&nfsi->rwsem); | |
297 | up_read(&clp->cl_sem); | |
298 | nfs_msync_inode(inode); | |
299 | ||
300 | if (delegation != NULL) | |
301 | nfs_do_return_delegation(inode, delegation); | |
302 | iput(inode); | |
303 | module_put_and_exit(0); | |
304 | } | |
305 | ||
306 | /* | |
307 | * Asynchronous delegation recall! | |
308 | */ | |
309 | int nfs_async_inode_return_delegation(struct inode *inode, const nfs4_stateid *stateid) | |
310 | { | |
311 | struct recall_threadargs data = { | |
312 | .inode = inode, | |
313 | .stateid = stateid, | |
314 | }; | |
315 | int status; | |
316 | ||
317 | init_completion(&data.started); | |
318 | __module_get(THIS_MODULE); | |
319 | status = kernel_thread(recall_thread, &data, CLONE_KERNEL); | |
320 | if (status < 0) | |
321 | goto out_module_put; | |
322 | wait_for_completion(&data.started); | |
323 | return data.result; | |
324 | out_module_put: | |
325 | module_put(THIS_MODULE); | |
326 | return status; | |
327 | } | |
328 | ||
329 | /* | |
330 | * Retrieve the inode associated with a delegation | |
331 | */ | |
332 | struct inode *nfs_delegation_find_inode(struct nfs4_client *clp, const struct nfs_fh *fhandle) | |
333 | { | |
334 | struct nfs_delegation *delegation; | |
335 | struct inode *res = NULL; | |
336 | spin_lock(&clp->cl_lock); | |
337 | list_for_each_entry(delegation, &clp->cl_delegations, super_list) { | |
338 | if (nfs_compare_fh(fhandle, &NFS_I(delegation->inode)->fh) == 0) { | |
339 | res = igrab(delegation->inode); | |
340 | break; | |
341 | } | |
342 | } | |
343 | spin_unlock(&clp->cl_lock); | |
344 | return res; | |
345 | } | |
346 | ||
347 | /* | |
348 | * Mark all delegations as needing to be reclaimed | |
349 | */ | |
350 | void nfs_delegation_mark_reclaim(struct nfs4_client *clp) | |
351 | { | |
352 | struct nfs_delegation *delegation; | |
353 | spin_lock(&clp->cl_lock); | |
354 | list_for_each_entry(delegation, &clp->cl_delegations, super_list) | |
355 | delegation->flags |= NFS_DELEGATION_NEED_RECLAIM; | |
356 | spin_unlock(&clp->cl_lock); | |
357 | } | |
358 | ||
359 | /* | |
360 | * Reap all unclaimed delegations after reboot recovery is done | |
361 | */ | |
362 | void nfs_delegation_reap_unclaimed(struct nfs4_client *clp) | |
363 | { | |
364 | struct nfs_delegation *delegation, *n; | |
365 | LIST_HEAD(head); | |
366 | spin_lock(&clp->cl_lock); | |
367 | list_for_each_entry_safe(delegation, n, &clp->cl_delegations, super_list) { | |
368 | if ((delegation->flags & NFS_DELEGATION_NEED_RECLAIM) == 0) | |
369 | continue; | |
370 | list_move(&delegation->super_list, &head); | |
371 | NFS_I(delegation->inode)->delegation = NULL; | |
372 | NFS_I(delegation->inode)->delegation_state = 0; | |
373 | } | |
374 | spin_unlock(&clp->cl_lock); | |
375 | while(!list_empty(&head)) { | |
376 | delegation = list_entry(head.next, struct nfs_delegation, super_list); | |
377 | list_del(&delegation->super_list); | |
378 | nfs_free_delegation(delegation); | |
379 | } | |
380 | } |