2 * linux/fs/nfs/delegation.c
4 * Copyright (C) 2004 Trond Myklebust
6 * NFS file delegation management
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>
15 #include <linux/nfs4.h>
16 #include <linux/nfs_fs.h>
17 #include <linux/nfs_xdr.h>
20 #include "delegation.h"
22 static struct nfs_delegation
*nfs_alloc_delegation(void)
24 return (struct nfs_delegation
*)kmalloc(sizeof(struct nfs_delegation
), GFP_KERNEL
);
27 static void nfs_free_delegation(struct nfs_delegation
*delegation
)
30 put_rpccred(delegation
->cred
);
34 static void nfs_delegation_claim_opens(struct inode
*inode
)
36 struct nfs_inode
*nfsi
= NFS_I(inode
);
37 struct nfs_open_context
*ctx
;
38 struct nfs4_state
*state
;
41 spin_lock(&inode
->i_lock
);
42 list_for_each_entry(ctx
, &nfsi
->open_files
, list
) {
46 if (!test_bit(NFS_DELEGATED_STATE
, &state
->flags
))
48 get_nfs_open_context(ctx
);
49 spin_unlock(&inode
->i_lock
);
50 if (nfs4_open_delegation_recall(ctx
->dentry
, state
) < 0)
52 put_nfs_open_context(ctx
);
55 spin_unlock(&inode
->i_lock
);
59 * Set up a delegation on an inode
61 void nfs_inode_reclaim_delegation(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_openres
*res
)
63 struct nfs_delegation
*delegation
= NFS_I(inode
)->delegation
;
65 if (delegation
== NULL
)
67 memcpy(delegation
->stateid
.data
, res
->delegation
.data
,
68 sizeof(delegation
->stateid
.data
));
69 delegation
->type
= res
->delegation_type
;
70 delegation
->maxsize
= res
->maxsize
;
72 delegation
->cred
= get_rpccred(cred
);
73 delegation
->flags
&= ~NFS_DELEGATION_NEED_RECLAIM
;
74 NFS_I(inode
)->delegation_state
= delegation
->type
;
79 * Set up a delegation on an inode
81 int nfs_inode_set_delegation(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_openres
*res
)
83 struct nfs4_client
*clp
= NFS_SERVER(inode
)->nfs4_state
;
84 struct nfs_inode
*nfsi
= NFS_I(inode
);
85 struct nfs_delegation
*delegation
;
88 /* Ensure we first revalidate the attributes and page cache! */
89 if ((nfsi
->cache_validity
& (NFS_INO_REVAL_PAGECACHE
|NFS_INO_INVALID_ATTR
)))
90 __nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
92 delegation
= nfs_alloc_delegation();
93 if (delegation
== NULL
)
95 memcpy(delegation
->stateid
.data
, res
->delegation
.data
,
96 sizeof(delegation
->stateid
.data
));
97 delegation
->type
= res
->delegation_type
;
98 delegation
->maxsize
= res
->maxsize
;
99 delegation
->cred
= get_rpccred(cred
);
100 delegation
->inode
= inode
;
102 spin_lock(&clp
->cl_lock
);
103 if (nfsi
->delegation
== NULL
) {
104 list_add(&delegation
->super_list
, &clp
->cl_delegations
);
105 nfsi
->delegation
= delegation
;
106 nfsi
->delegation_state
= delegation
->type
;
109 if (memcmp(&delegation
->stateid
, &nfsi
->delegation
->stateid
,
110 sizeof(delegation
->stateid
)) != 0 ||
111 delegation
->type
!= nfsi
->delegation
->type
) {
112 printk("%s: server %u.%u.%u.%u, handed out a duplicate delegation!\n",
113 __FUNCTION__
, NIPQUAD(clp
->cl_addr
));
117 spin_unlock(&clp
->cl_lock
);
118 if (delegation
!= NULL
)
123 static int nfs_do_return_delegation(struct inode
*inode
, struct nfs_delegation
*delegation
)
127 __nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
129 res
= nfs4_proc_delegreturn(inode
, delegation
->cred
, &delegation
->stateid
);
130 nfs_free_delegation(delegation
);
134 /* Sync all data to disk upon delegation return */
135 static void nfs_msync_inode(struct inode
*inode
)
137 filemap_fdatawrite(inode
->i_mapping
);
139 filemap_fdatawait(inode
->i_mapping
);
143 * Basic procedure for returning a delegation to the server
145 int nfs_inode_return_delegation(struct inode
*inode
)
147 struct nfs4_client
*clp
= NFS_SERVER(inode
)->nfs4_state
;
148 struct nfs_inode
*nfsi
= NFS_I(inode
);
149 struct nfs_delegation
*delegation
;
152 nfs_msync_inode(inode
);
153 down_read(&clp
->cl_sem
);
154 /* Guard against new delegated open calls */
155 down_write(&nfsi
->rwsem
);
156 spin_lock(&clp
->cl_lock
);
157 delegation
= nfsi
->delegation
;
158 if (delegation
!= NULL
) {
159 list_del_init(&delegation
->super_list
);
160 nfsi
->delegation
= NULL
;
161 nfsi
->delegation_state
= 0;
163 spin_unlock(&clp
->cl_lock
);
164 nfs_delegation_claim_opens(inode
);
165 up_write(&nfsi
->rwsem
);
166 up_read(&clp
->cl_sem
);
167 nfs_msync_inode(inode
);
169 if (delegation
!= NULL
)
170 res
= nfs_do_return_delegation(inode
, delegation
);
175 * Return all delegations associated to a super block
177 void nfs_return_all_delegations(struct super_block
*sb
)
179 struct nfs4_client
*clp
= NFS_SB(sb
)->nfs4_state
;
180 struct nfs_delegation
*delegation
;
186 spin_lock(&clp
->cl_lock
);
187 list_for_each_entry(delegation
, &clp
->cl_delegations
, super_list
) {
188 if (delegation
->inode
->i_sb
!= sb
)
190 inode
= igrab(delegation
->inode
);
193 spin_unlock(&clp
->cl_lock
);
194 nfs_inode_return_delegation(inode
);
198 spin_unlock(&clp
->cl_lock
);
202 * Return all delegations following an NFS4ERR_CB_PATH_DOWN error.
204 void nfs_handle_cb_pathdown(struct nfs4_client
*clp
)
206 struct nfs_delegation
*delegation
;
212 spin_lock(&clp
->cl_lock
);
213 list_for_each_entry(delegation
, &clp
->cl_delegations
, super_list
) {
214 inode
= igrab(delegation
->inode
);
217 spin_unlock(&clp
->cl_lock
);
218 nfs_inode_return_delegation(inode
);
222 spin_unlock(&clp
->cl_lock
);
225 struct recall_threadargs
{
227 struct nfs4_client
*clp
;
228 const nfs4_stateid
*stateid
;
230 struct completion started
;
234 static int recall_thread(void *data
)
236 struct recall_threadargs
*args
= (struct recall_threadargs
*)data
;
237 struct inode
*inode
= igrab(args
->inode
);
238 struct nfs4_client
*clp
= NFS_SERVER(inode
)->nfs4_state
;
239 struct nfs_inode
*nfsi
= NFS_I(inode
);
240 struct nfs_delegation
*delegation
;
242 daemonize("nfsv4-delegreturn");
244 nfs_msync_inode(inode
);
245 down_read(&clp
->cl_sem
);
246 down_write(&nfsi
->rwsem
);
247 spin_lock(&clp
->cl_lock
);
248 delegation
= nfsi
->delegation
;
249 if (delegation
!= NULL
&& memcmp(delegation
->stateid
.data
,
251 sizeof(delegation
->stateid
.data
)) == 0) {
252 list_del_init(&delegation
->super_list
);
253 nfsi
->delegation
= NULL
;
254 nfsi
->delegation_state
= 0;
258 args
->result
= -ENOENT
;
260 spin_unlock(&clp
->cl_lock
);
261 complete(&args
->started
);
262 nfs_delegation_claim_opens(inode
);
263 up_write(&nfsi
->rwsem
);
264 up_read(&clp
->cl_sem
);
265 nfs_msync_inode(inode
);
267 if (delegation
!= NULL
)
268 nfs_do_return_delegation(inode
, delegation
);
270 module_put_and_exit(0);
274 * Asynchronous delegation recall!
276 int nfs_async_inode_return_delegation(struct inode
*inode
, const nfs4_stateid
*stateid
)
278 struct recall_threadargs data
= {
284 init_completion(&data
.started
);
285 __module_get(THIS_MODULE
);
286 status
= kernel_thread(recall_thread
, &data
, CLONE_KERNEL
);
289 wait_for_completion(&data
.started
);
292 module_put(THIS_MODULE
);
297 * Retrieve the inode associated with a delegation
299 struct inode
*nfs_delegation_find_inode(struct nfs4_client
*clp
, const struct nfs_fh
*fhandle
)
301 struct nfs_delegation
*delegation
;
302 struct inode
*res
= NULL
;
303 spin_lock(&clp
->cl_lock
);
304 list_for_each_entry(delegation
, &clp
->cl_delegations
, super_list
) {
305 if (nfs_compare_fh(fhandle
, &NFS_I(delegation
->inode
)->fh
) == 0) {
306 res
= igrab(delegation
->inode
);
310 spin_unlock(&clp
->cl_lock
);
315 * Mark all delegations as needing to be reclaimed
317 void nfs_delegation_mark_reclaim(struct nfs4_client
*clp
)
319 struct nfs_delegation
*delegation
;
320 spin_lock(&clp
->cl_lock
);
321 list_for_each_entry(delegation
, &clp
->cl_delegations
, super_list
)
322 delegation
->flags
|= NFS_DELEGATION_NEED_RECLAIM
;
323 spin_unlock(&clp
->cl_lock
);
327 * Reap all unclaimed delegations after reboot recovery is done
329 void nfs_delegation_reap_unclaimed(struct nfs4_client
*clp
)
331 struct nfs_delegation
*delegation
, *n
;
333 spin_lock(&clp
->cl_lock
);
334 list_for_each_entry_safe(delegation
, n
, &clp
->cl_delegations
, super_list
) {
335 if ((delegation
->flags
& NFS_DELEGATION_NEED_RECLAIM
) == 0)
337 list_move(&delegation
->super_list
, &head
);
338 NFS_I(delegation
->inode
)->delegation
= NULL
;
339 NFS_I(delegation
->inode
)->delegation_state
= 0;
341 spin_unlock(&clp
->cl_lock
);
342 while(!list_empty(&head
)) {
343 delegation
= list_entry(head
.next
, struct nfs_delegation
, super_list
);
344 list_del(&delegation
->super_list
);
345 nfs_free_delegation(delegation
);