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