2 * linux/fs/nfs/delegation.c
4 * Copyright (C) 2004 Trond Myklebust
6 * NFS file delegation management
9 #include <linux/completion.h>
10 #include <linux/kthread.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"
23 static void nfs_free_delegation(struct nfs_delegation
*delegation
)
26 put_rpccred(delegation
->cred
);
30 static void nfs_free_delegation_callback(struct rcu_head
*head
)
32 struct nfs_delegation
*delegation
= container_of(head
, struct nfs_delegation
, rcu
);
34 nfs_free_delegation(delegation
);
37 static int nfs_delegation_claim_locks(struct nfs_open_context
*ctx
, struct nfs4_state
*state
)
39 struct inode
*inode
= state
->inode
;
43 for (fl
= inode
->i_flock
; fl
!= 0; fl
= fl
->fl_next
) {
44 if (!(fl
->fl_flags
& (FL_POSIX
|FL_FLOCK
)))
46 if ((struct nfs_open_context
*)fl
->fl_file
->private_data
!= ctx
)
48 status
= nfs4_lock_delegation_recall(state
, fl
);
53 printk(KERN_ERR
"%s: unhandled error %d.\n",
54 __FUNCTION__
, status
);
55 case -NFS4ERR_EXPIRED
:
56 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
57 case -NFS4ERR_STALE_CLIENTID
:
58 nfs4_schedule_state_recovery(NFS_SERVER(inode
)->nfs_client
);
67 static void nfs_delegation_claim_opens(struct inode
*inode
, const nfs4_stateid
*stateid
)
69 struct nfs_inode
*nfsi
= NFS_I(inode
);
70 struct nfs_open_context
*ctx
;
71 struct nfs4_state
*state
;
75 spin_lock(&inode
->i_lock
);
76 list_for_each_entry(ctx
, &nfsi
->open_files
, list
) {
80 if (!test_bit(NFS_DELEGATED_STATE
, &state
->flags
))
82 if (memcmp(state
->stateid
.data
, stateid
->data
, sizeof(state
->stateid
.data
)) != 0)
84 get_nfs_open_context(ctx
);
85 spin_unlock(&inode
->i_lock
);
86 err
= nfs4_open_delegation_recall(ctx
, state
, stateid
);
88 err
= nfs_delegation_claim_locks(ctx
, state
);
89 put_nfs_open_context(ctx
);
94 spin_unlock(&inode
->i_lock
);
98 * Set up a delegation on an inode
100 void nfs_inode_reclaim_delegation(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_openres
*res
)
102 struct nfs_delegation
*delegation
= NFS_I(inode
)->delegation
;
104 if (delegation
== NULL
)
106 memcpy(delegation
->stateid
.data
, res
->delegation
.data
,
107 sizeof(delegation
->stateid
.data
));
108 delegation
->type
= res
->delegation_type
;
109 delegation
->maxsize
= res
->maxsize
;
111 delegation
->cred
= get_rpccred(cred
);
112 delegation
->flags
&= ~NFS_DELEGATION_NEED_RECLAIM
;
113 NFS_I(inode
)->delegation_state
= delegation
->type
;
118 * Set up a delegation on an inode
120 int nfs_inode_set_delegation(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_openres
*res
)
122 struct nfs_client
*clp
= NFS_SERVER(inode
)->nfs_client
;
123 struct nfs_inode
*nfsi
= NFS_I(inode
);
124 struct nfs_delegation
*delegation
;
127 delegation
= kmalloc(sizeof(*delegation
), GFP_KERNEL
);
128 if (delegation
== NULL
)
130 memcpy(delegation
->stateid
.data
, res
->delegation
.data
,
131 sizeof(delegation
->stateid
.data
));
132 delegation
->type
= res
->delegation_type
;
133 delegation
->maxsize
= res
->maxsize
;
134 delegation
->change_attr
= nfsi
->change_attr
;
135 delegation
->cred
= get_rpccred(cred
);
136 delegation
->inode
= inode
;
138 spin_lock(&clp
->cl_lock
);
139 if (rcu_dereference(nfsi
->delegation
) == NULL
) {
140 list_add_rcu(&delegation
->super_list
, &clp
->cl_delegations
);
141 nfsi
->delegation_state
= delegation
->type
;
142 rcu_assign_pointer(nfsi
->delegation
, delegation
);
145 if (memcmp(&delegation
->stateid
, &nfsi
->delegation
->stateid
,
146 sizeof(delegation
->stateid
)) != 0 ||
147 delegation
->type
!= nfsi
->delegation
->type
) {
148 printk("%s: server %u.%u.%u.%u, handed out a duplicate delegation!\n",
149 __FUNCTION__
, NIPQUAD(clp
->cl_addr
.sin_addr
));
154 /* Ensure we revalidate the attributes and page cache! */
155 spin_lock(&inode
->i_lock
);
156 nfsi
->cache_validity
|= NFS_INO_REVAL_FORCED
;
157 spin_unlock(&inode
->i_lock
);
159 spin_unlock(&clp
->cl_lock
);
164 static int nfs_do_return_delegation(struct inode
*inode
, struct nfs_delegation
*delegation
)
168 res
= nfs4_proc_delegreturn(inode
, delegation
->cred
, &delegation
->stateid
);
169 call_rcu(&delegation
->rcu
, nfs_free_delegation_callback
);
173 /* Sync all data to disk upon delegation return */
174 static void nfs_msync_inode(struct inode
*inode
)
176 filemap_fdatawrite(inode
->i_mapping
);
178 filemap_fdatawait(inode
->i_mapping
);
182 * Basic procedure for returning a delegation to the server
184 static int __nfs_inode_return_delegation(struct inode
*inode
, struct nfs_delegation
*delegation
)
186 struct nfs_client
*clp
= NFS_SERVER(inode
)->nfs_client
;
187 struct nfs_inode
*nfsi
= NFS_I(inode
);
189 nfs_msync_inode(inode
);
190 down_read(&clp
->cl_sem
);
191 /* Guard against new delegated open calls */
192 down_write(&nfsi
->rwsem
);
193 nfs_delegation_claim_opens(inode
, &delegation
->stateid
);
194 up_write(&nfsi
->rwsem
);
195 up_read(&clp
->cl_sem
);
196 nfs_msync_inode(inode
);
198 return nfs_do_return_delegation(inode
, delegation
);
201 static struct nfs_delegation
*nfs_detach_delegation_locked(struct nfs_inode
*nfsi
, const nfs4_stateid
*stateid
)
203 struct nfs_delegation
*delegation
= rcu_dereference(nfsi
->delegation
);
205 if (delegation
== NULL
)
207 if (stateid
!= NULL
&& memcmp(delegation
->stateid
.data
, stateid
->data
,
208 sizeof(delegation
->stateid
.data
)) != 0)
210 list_del_rcu(&delegation
->super_list
);
211 nfsi
->delegation_state
= 0;
212 rcu_assign_pointer(nfsi
->delegation
, NULL
);
218 int nfs_inode_return_delegation(struct inode
*inode
)
220 struct nfs_client
*clp
= NFS_SERVER(inode
)->nfs_client
;
221 struct nfs_inode
*nfsi
= NFS_I(inode
);
222 struct nfs_delegation
*delegation
;
225 if (rcu_dereference(nfsi
->delegation
) != NULL
) {
226 spin_lock(&clp
->cl_lock
);
227 delegation
= nfs_detach_delegation_locked(nfsi
, NULL
);
228 spin_unlock(&clp
->cl_lock
);
229 if (delegation
!= NULL
)
230 err
= __nfs_inode_return_delegation(inode
, delegation
);
236 * Return all delegations associated to a super block
238 void nfs_return_all_delegations(struct super_block
*sb
)
240 struct nfs_client
*clp
= NFS_SB(sb
)->nfs_client
;
241 struct nfs_delegation
*delegation
;
248 list_for_each_entry_rcu(delegation
, &clp
->cl_delegations
, super_list
) {
249 if (delegation
->inode
->i_sb
!= sb
)
251 inode
= igrab(delegation
->inode
);
254 spin_lock(&clp
->cl_lock
);
255 delegation
= nfs_detach_delegation_locked(NFS_I(inode
), NULL
);
256 spin_unlock(&clp
->cl_lock
);
258 if (delegation
!= NULL
)
259 __nfs_inode_return_delegation(inode
, delegation
);
266 static int nfs_do_expire_all_delegations(void *ptr
)
268 struct nfs_client
*clp
= ptr
;
269 struct nfs_delegation
*delegation
;
272 allow_signal(SIGKILL
);
274 if (test_bit(NFS4CLNT_STATE_RECOVER
, &clp
->cl_state
) != 0)
276 if (test_bit(NFS4CLNT_LEASE_EXPIRED
, &clp
->cl_state
) == 0)
279 list_for_each_entry_rcu(delegation
, &clp
->cl_delegations
, super_list
) {
280 inode
= igrab(delegation
->inode
);
283 spin_lock(&clp
->cl_lock
);
284 delegation
= nfs_detach_delegation_locked(NFS_I(inode
), NULL
);
285 spin_unlock(&clp
->cl_lock
);
288 __nfs_inode_return_delegation(inode
, delegation
);
295 module_put_and_exit(0);
298 void nfs_expire_all_delegations(struct nfs_client
*clp
)
300 struct task_struct
*task
;
302 __module_get(THIS_MODULE
);
303 atomic_inc(&clp
->cl_count
);
304 task
= kthread_run(nfs_do_expire_all_delegations
, clp
,
305 "%u.%u.%u.%u-delegreturn",
306 NIPQUAD(clp
->cl_addr
.sin_addr
));
310 module_put(THIS_MODULE
);
314 * Return all delegations following an NFS4ERR_CB_PATH_DOWN error.
316 void nfs_handle_cb_pathdown(struct nfs_client
*clp
)
318 struct nfs_delegation
*delegation
;
325 list_for_each_entry_rcu(delegation
, &clp
->cl_delegations
, super_list
) {
326 inode
= igrab(delegation
->inode
);
329 spin_lock(&clp
->cl_lock
);
330 delegation
= nfs_detach_delegation_locked(NFS_I(inode
), NULL
);
331 spin_unlock(&clp
->cl_lock
);
333 if (delegation
!= NULL
)
334 __nfs_inode_return_delegation(inode
, delegation
);
341 struct recall_threadargs
{
343 struct nfs_client
*clp
;
344 const nfs4_stateid
*stateid
;
346 struct completion started
;
350 static int recall_thread(void *data
)
352 struct recall_threadargs
*args
= (struct recall_threadargs
*)data
;
353 struct inode
*inode
= igrab(args
->inode
);
354 struct nfs_client
*clp
= NFS_SERVER(inode
)->nfs_client
;
355 struct nfs_inode
*nfsi
= NFS_I(inode
);
356 struct nfs_delegation
*delegation
;
358 daemonize("nfsv4-delegreturn");
360 nfs_msync_inode(inode
);
361 down_read(&clp
->cl_sem
);
362 down_write(&nfsi
->rwsem
);
363 spin_lock(&clp
->cl_lock
);
364 delegation
= nfs_detach_delegation_locked(nfsi
, args
->stateid
);
365 if (delegation
!= NULL
)
368 args
->result
= -ENOENT
;
369 spin_unlock(&clp
->cl_lock
);
370 complete(&args
->started
);
371 nfs_delegation_claim_opens(inode
, args
->stateid
);
372 up_write(&nfsi
->rwsem
);
373 up_read(&clp
->cl_sem
);
374 nfs_msync_inode(inode
);
376 if (delegation
!= NULL
)
377 nfs_do_return_delegation(inode
, delegation
);
379 module_put_and_exit(0);
383 * Asynchronous delegation recall!
385 int nfs_async_inode_return_delegation(struct inode
*inode
, const nfs4_stateid
*stateid
)
387 struct recall_threadargs data
= {
393 init_completion(&data
.started
);
394 __module_get(THIS_MODULE
);
395 status
= kernel_thread(recall_thread
, &data
, CLONE_KERNEL
);
398 wait_for_completion(&data
.started
);
401 module_put(THIS_MODULE
);
406 * Retrieve the inode associated with a delegation
408 struct inode
*nfs_delegation_find_inode(struct nfs_client
*clp
, const struct nfs_fh
*fhandle
)
410 struct nfs_delegation
*delegation
;
411 struct inode
*res
= NULL
;
413 list_for_each_entry_rcu(delegation
, &clp
->cl_delegations
, super_list
) {
414 if (nfs_compare_fh(fhandle
, &NFS_I(delegation
->inode
)->fh
) == 0) {
415 res
= igrab(delegation
->inode
);
424 * Mark all delegations as needing to be reclaimed
426 void nfs_delegation_mark_reclaim(struct nfs_client
*clp
)
428 struct nfs_delegation
*delegation
;
430 list_for_each_entry_rcu(delegation
, &clp
->cl_delegations
, super_list
)
431 delegation
->flags
|= NFS_DELEGATION_NEED_RECLAIM
;
436 * Reap all unclaimed delegations after reboot recovery is done
438 void nfs_delegation_reap_unclaimed(struct nfs_client
*clp
)
440 struct nfs_delegation
*delegation
;
443 list_for_each_entry_rcu(delegation
, &clp
->cl_delegations
, super_list
) {
444 if ((delegation
->flags
& NFS_DELEGATION_NEED_RECLAIM
) == 0)
446 spin_lock(&clp
->cl_lock
);
447 delegation
= nfs_detach_delegation_locked(NFS_I(delegation
->inode
), NULL
);
448 spin_unlock(&clp
->cl_lock
);
450 if (delegation
!= NULL
)
451 call_rcu(&delegation
->rcu
, nfs_free_delegation_callback
);
457 int nfs4_copy_delegation_stateid(nfs4_stateid
*dst
, struct inode
*inode
)
459 struct nfs_inode
*nfsi
= NFS_I(inode
);
460 struct nfs_delegation
*delegation
;
464 delegation
= rcu_dereference(nfsi
->delegation
);
465 if (delegation
!= NULL
) {
466 memcpy(dst
->data
, delegation
->stateid
.data
, sizeof(dst
->data
));