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 int nfs_delegation_claim_locks(struct nfs_open_context *ctx, struct nfs4_state *state)
32 struct inode *inode = state->inode;
36 for (fl = inode->i_flock; fl != 0; fl = fl->fl_next) {
37 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
39 if ((struct nfs_open_context *)fl->fl_file->private_data != ctx)
41 status = nfs4_lock_delegation_recall(state, fl);
46 printk(KERN_ERR "%s: unhandled error %d.\n",
47 __FUNCTION__, status);
48 case -NFS4ERR_EXPIRED:
49 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
50 case -NFS4ERR_STALE_CLIENTID:
51 nfs4_schedule_state_recovery(NFS_SERVER(inode)->nfs_client);
60 static void nfs_delegation_claim_opens(struct inode *inode, const nfs4_stateid *stateid)
62 struct nfs_inode *nfsi = NFS_I(inode);
63 struct nfs_open_context *ctx;
64 struct nfs4_state *state;
68 spin_lock(&inode->i_lock);
69 list_for_each_entry(ctx, &nfsi->open_files, list) {
73 if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
75 if (memcmp(state->stateid.data, stateid->data, sizeof(state->stateid.data)) != 0)
77 get_nfs_open_context(ctx);
78 spin_unlock(&inode->i_lock);
79 err = nfs4_open_delegation_recall(ctx, state);
81 err = nfs_delegation_claim_locks(ctx, state);
82 put_nfs_open_context(ctx);
87 spin_unlock(&inode->i_lock);
91 * Set up a delegation on an inode
93 void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res)
95 struct nfs_delegation *delegation = NFS_I(inode)->delegation;
97 if (delegation == NULL)
99 memcpy(delegation->stateid.data, res->delegation.data,
100 sizeof(delegation->stateid.data));
101 delegation->type = res->delegation_type;
102 delegation->maxsize = res->maxsize;
104 delegation->cred = get_rpccred(cred);
105 delegation->flags &= ~NFS_DELEGATION_NEED_RECLAIM;
106 NFS_I(inode)->delegation_state = delegation->type;
111 * Set up a delegation on an inode
113 int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res)
115 struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
116 struct nfs_inode *nfsi = NFS_I(inode);
117 struct nfs_delegation *delegation;
120 /* Ensure we first revalidate the attributes and page cache! */
121 if ((nfsi->cache_validity & (NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_ATTR)))
122 __nfs_revalidate_inode(NFS_SERVER(inode), inode);
124 delegation = kmalloc(sizeof(*delegation), GFP_KERNEL);
125 if (delegation == NULL)
127 memcpy(delegation->stateid.data, res->delegation.data,
128 sizeof(delegation->stateid.data));
129 delegation->type = res->delegation_type;
130 delegation->maxsize = res->maxsize;
131 delegation->change_attr = nfsi->change_attr;
132 delegation->cred = get_rpccred(cred);
133 delegation->inode = inode;
135 spin_lock(&clp->cl_lock);
136 if (nfsi->delegation == NULL) {
137 list_add(&delegation->super_list, &clp->cl_delegations);
138 nfsi->delegation = delegation;
139 nfsi->delegation_state = delegation->type;
142 if (memcmp(&delegation->stateid, &nfsi->delegation->stateid,
143 sizeof(delegation->stateid)) != 0 ||
144 delegation->type != nfsi->delegation->type) {
145 printk("%s: server %u.%u.%u.%u, handed out a duplicate delegation!\n",
146 __FUNCTION__, NIPQUAD(clp->cl_addr.sin_addr));
150 spin_unlock(&clp->cl_lock);
155 static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation)
159 res = nfs4_proc_delegreturn(inode, delegation->cred, &delegation->stateid);
160 nfs_free_delegation(delegation);
164 /* Sync all data to disk upon delegation return */
165 static void nfs_msync_inode(struct inode *inode)
167 filemap_fdatawrite(inode->i_mapping);
169 filemap_fdatawait(inode->i_mapping);
173 * Basic procedure for returning a delegation to the server
175 static int __nfs_inode_return_delegation(struct inode *inode, struct nfs_delegation *delegation)
177 struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
178 struct nfs_inode *nfsi = NFS_I(inode);
180 nfs_msync_inode(inode);
181 down_read(&clp->cl_sem);
182 /* Guard against new delegated open calls */
183 down_write(&nfsi->rwsem);
184 nfs_delegation_claim_opens(inode, &delegation->stateid);
185 up_write(&nfsi->rwsem);
186 up_read(&clp->cl_sem);
187 nfs_msync_inode(inode);
189 return nfs_do_return_delegation(inode, delegation);
192 static struct nfs_delegation *nfs_detach_delegation_locked(struct nfs_inode *nfsi, const nfs4_stateid *stateid)
194 struct nfs_delegation *delegation = nfsi->delegation;
196 if (delegation == NULL)
198 if (stateid != NULL && memcmp(delegation->stateid.data, stateid->data,
199 sizeof(delegation->stateid.data)) != 0)
201 list_del_init(&delegation->super_list);
202 nfsi->delegation = NULL;
203 nfsi->delegation_state = 0;
209 int nfs_inode_return_delegation(struct inode *inode)
211 struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
212 struct nfs_inode *nfsi = NFS_I(inode);
213 struct nfs_delegation *delegation;
216 if (nfsi->delegation_state != 0) {
217 spin_lock(&clp->cl_lock);
218 delegation = nfs_detach_delegation_locked(nfsi, NULL);
219 spin_unlock(&clp->cl_lock);
220 if (delegation != NULL)
221 err = __nfs_inode_return_delegation(inode, delegation);
227 * Return all delegations associated to a super block
229 void nfs_return_all_delegations(struct super_block *sb)
231 struct nfs_client *clp = NFS_SB(sb)->nfs_client;
232 struct nfs_delegation *delegation;
238 spin_lock(&clp->cl_lock);
239 list_for_each_entry(delegation, &clp->cl_delegations, super_list) {
240 if (delegation->inode->i_sb != sb)
242 inode = igrab(delegation->inode);
245 nfs_detach_delegation_locked(NFS_I(inode), NULL);
246 spin_unlock(&clp->cl_lock);
247 __nfs_inode_return_delegation(inode, delegation);
251 spin_unlock(&clp->cl_lock);
254 static int nfs_do_expire_all_delegations(void *ptr)
256 struct nfs_client *clp = ptr;
257 struct nfs_delegation *delegation;
260 allow_signal(SIGKILL);
262 spin_lock(&clp->cl_lock);
263 if (test_bit(NFS4CLNT_STATE_RECOVER, &clp->cl_state) != 0)
265 if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0)
267 list_for_each_entry(delegation, &clp->cl_delegations, super_list) {
268 inode = igrab(delegation->inode);
271 nfs_detach_delegation_locked(NFS_I(inode), NULL);
272 spin_unlock(&clp->cl_lock);
273 __nfs_inode_return_delegation(inode, delegation);
278 spin_unlock(&clp->cl_lock);
280 module_put_and_exit(0);
283 void nfs_expire_all_delegations(struct nfs_client *clp)
285 struct task_struct *task;
287 __module_get(THIS_MODULE);
288 atomic_inc(&clp->cl_count);
289 task = kthread_run(nfs_do_expire_all_delegations, clp,
290 "%u.%u.%u.%u-delegreturn",
291 NIPQUAD(clp->cl_addr.sin_addr));
295 module_put(THIS_MODULE);
299 * Return all delegations following an NFS4ERR_CB_PATH_DOWN error.
301 void nfs_handle_cb_pathdown(struct nfs_client *clp)
303 struct nfs_delegation *delegation;
309 spin_lock(&clp->cl_lock);
310 list_for_each_entry(delegation, &clp->cl_delegations, super_list) {
311 inode = igrab(delegation->inode);
314 nfs_detach_delegation_locked(NFS_I(inode), NULL);
315 spin_unlock(&clp->cl_lock);
316 __nfs_inode_return_delegation(inode, delegation);
320 spin_unlock(&clp->cl_lock);
323 struct recall_threadargs {
325 struct nfs_client *clp;
326 const nfs4_stateid *stateid;
328 struct completion started;
332 static int recall_thread(void *data)
334 struct recall_threadargs *args = (struct recall_threadargs *)data;
335 struct inode *inode = igrab(args->inode);
336 struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
337 struct nfs_inode *nfsi = NFS_I(inode);
338 struct nfs_delegation *delegation;
340 daemonize("nfsv4-delegreturn");
342 nfs_msync_inode(inode);
343 down_read(&clp->cl_sem);
344 down_write(&nfsi->rwsem);
345 spin_lock(&clp->cl_lock);
346 delegation = nfs_detach_delegation_locked(nfsi, args->stateid);
347 if (delegation != NULL)
350 args->result = -ENOENT;
351 spin_unlock(&clp->cl_lock);
352 complete(&args->started);
353 nfs_delegation_claim_opens(inode, args->stateid);
354 up_write(&nfsi->rwsem);
355 up_read(&clp->cl_sem);
356 nfs_msync_inode(inode);
358 if (delegation != NULL)
359 nfs_do_return_delegation(inode, delegation);
361 module_put_and_exit(0);
365 * Asynchronous delegation recall!
367 int nfs_async_inode_return_delegation(struct inode *inode, const nfs4_stateid *stateid)
369 struct recall_threadargs data = {
375 init_completion(&data.started);
376 __module_get(THIS_MODULE);
377 status = kernel_thread(recall_thread, &data, CLONE_KERNEL);
380 wait_for_completion(&data.started);
383 module_put(THIS_MODULE);
388 * Retrieve the inode associated with a delegation
390 struct inode *nfs_delegation_find_inode(struct nfs_client *clp, const struct nfs_fh *fhandle)
392 struct nfs_delegation *delegation;
393 struct inode *res = NULL;
394 spin_lock(&clp->cl_lock);
395 list_for_each_entry(delegation, &clp->cl_delegations, super_list) {
396 if (nfs_compare_fh(fhandle, &NFS_I(delegation->inode)->fh) == 0) {
397 res = igrab(delegation->inode);
401 spin_unlock(&clp->cl_lock);
406 * Mark all delegations as needing to be reclaimed
408 void nfs_delegation_mark_reclaim(struct nfs_client *clp)
410 struct nfs_delegation *delegation;
411 spin_lock(&clp->cl_lock);
412 list_for_each_entry(delegation, &clp->cl_delegations, super_list)
413 delegation->flags |= NFS_DELEGATION_NEED_RECLAIM;
414 spin_unlock(&clp->cl_lock);
418 * Reap all unclaimed delegations after reboot recovery is done
420 void nfs_delegation_reap_unclaimed(struct nfs_client *clp)
422 struct nfs_delegation *delegation, *n;
424 spin_lock(&clp->cl_lock);
425 list_for_each_entry_safe(delegation, n, &clp->cl_delegations, super_list) {
426 if ((delegation->flags & NFS_DELEGATION_NEED_RECLAIM) == 0)
428 list_move(&delegation->super_list, &head);
429 NFS_I(delegation->inode)->delegation = NULL;
430 NFS_I(delegation->inode)->delegation_state = 0;
432 spin_unlock(&clp->cl_lock);
433 while(!list_empty(&head)) {
434 delegation = list_entry(head.next, struct nfs_delegation, super_list);
435 list_del(&delegation->super_list);
436 nfs_free_delegation(delegation);
440 int nfs4_copy_delegation_stateid(nfs4_stateid *dst, struct inode *inode)
442 struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
443 struct nfs_inode *nfsi = NFS_I(inode);
444 struct nfs_delegation *delegation;
447 if (nfsi->delegation_state == 0)
449 spin_lock(&clp->cl_lock);
450 delegation = nfsi->delegation;
451 if (delegation != NULL) {
452 memcpy(dst->data, delegation->stateid.data, sizeof(dst->data));
455 spin_unlock(&clp->cl_lock);