+int nfs4_open_reclaim(struct nfs4_state_owner *sp, struct nfs4_state *state)
+{
+ struct nfs_server *server = NFS_SERVER(state->inode);
+ struct nfs4_exception exception = { };
+ int err;
+ do {
+ err = _nfs4_open_reclaim(sp, state);
+ switch (err) {
+ case 0:
+ case -NFS4ERR_STALE_CLIENTID:
+ case -NFS4ERR_STALE_STATEID:
+ case -NFS4ERR_EXPIRED:
+ return err;
+ }
+ err = nfs4_handle_exception(server, err, &exception);
+ } while (exception.retry);
+ return err;
+}
+
+static int _nfs4_open_delegation_recall(struct dentry *dentry, struct nfs4_state *state)
+{
+ struct nfs4_state_owner *sp = state->owner;
+ struct inode *inode = dentry->d_inode;
+ struct nfs_server *server = NFS_SERVER(inode);
+ struct dentry *parent = dget_parent(dentry);
+ struct nfs_openargs arg = {
+ .fh = NFS_FH(parent->d_inode),
+ .clientid = server->nfs4_state->cl_clientid,
+ .name = &dentry->d_name,
+ .id = sp->so_id,
+ .server = server,
+ .bitmask = server->attr_bitmask,
+ .claim = NFS4_OPEN_CLAIM_DELEGATE_CUR,
+ };
+ struct nfs_openres res = {
+ .server = server,
+ };
+ struct rpc_message msg = {
+ .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_OPEN_NOATTR],
+ .rpc_argp = &arg,
+ .rpc_resp = &res,
+ .rpc_cred = sp->so_cred,
+ };
+ int status = 0;
+
+ down(&sp->so_sema);
+ if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
+ goto out;
+ if (state->state == 0)
+ goto out;
+ arg.seqid = sp->so_seqid;
+ arg.open_flags = state->state;
+ memcpy(arg.u.delegation.data, state->stateid.data, sizeof(arg.u.delegation.data));
+ status = rpc_call_sync(server->client, &msg, RPC_TASK_NOINTR);
+ nfs4_increment_seqid(status, sp);
+ if (status >= 0) {
+ memcpy(state->stateid.data, res.stateid.data,
+ sizeof(state->stateid.data));
+ clear_bit(NFS_DELEGATED_STATE, &state->flags);
+ }
+out:
+ up(&sp->so_sema);
+ dput(parent);
+ return status;
+}
+
+int nfs4_open_delegation_recall(struct dentry *dentry, struct nfs4_state *state)
+{
+ struct nfs4_exception exception = { };
+ struct nfs_server *server = NFS_SERVER(dentry->d_inode);
+ int err;
+ do {
+ err = _nfs4_open_delegation_recall(dentry, state);
+ switch (err) {
+ case 0:
+ return err;
+ case -NFS4ERR_STALE_CLIENTID:
+ case -NFS4ERR_STALE_STATEID:
+ case -NFS4ERR_EXPIRED:
+ /* Don't recall a delegation if it was lost */
+ nfs4_schedule_state_recovery(server->nfs4_state);
+ return err;
+ }
+ err = nfs4_handle_exception(server, err, &exception);
+ } while (exception.retry);
+ return err;
+}
+
+static int _nfs4_proc_open_confirm(struct rpc_clnt *clnt, const struct nfs_fh *fh, struct nfs4_state_owner *sp, nfs4_stateid *stateid)
+{
+ struct nfs_open_confirmargs arg = {
+ .fh = fh,
+ .seqid = sp->so_seqid,
+ .stateid = *stateid,
+ };
+ struct nfs_open_confirmres res;
+ struct rpc_message msg = {
+ .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_OPEN_CONFIRM],
+ .rpc_argp = &arg,
+ .rpc_resp = &res,
+ .rpc_cred = sp->so_cred,
+ };
+ int status;
+
+ status = rpc_call_sync(clnt, &msg, RPC_TASK_NOINTR);
+ nfs4_increment_seqid(status, sp);
+ if (status >= 0)
+ memcpy(stateid, &res.stateid, sizeof(*stateid));
+ return status;
+}
+
+static int _nfs4_do_access(struct inode *inode, struct rpc_cred *cred, int mask)
+{
+ struct nfs_access_entry cache;
+ int status;
+
+ status = nfs_access_get_cached(inode, cred, &cache);
+ if (status == 0)
+ goto out;
+
+ /* Be clever: ask server to check for all possible rights */
+ cache.mask = MAY_EXEC | MAY_WRITE | MAY_READ;
+ cache.cred = cred;
+ cache.jiffies = jiffies;
+ status = _nfs4_proc_access(inode, &cache);
+ if (status != 0)
+ return status;
+ nfs_access_add_cache(inode, &cache);
+out:
+ if ((cache.mask & mask) == mask)
+ return 0;
+ return -EACCES;
+}
+
+/*
+ * Returns an nfs4_state + an extra reference to the inode
+ */
+int _nfs4_open_delegated(struct inode *inode, int flags, struct rpc_cred *cred, struct nfs4_state **res)
+{
+ struct nfs_delegation *delegation;
+ struct nfs_server *server = NFS_SERVER(inode);
+ struct nfs4_client *clp = server->nfs4_state;
+ struct nfs_inode *nfsi = NFS_I(inode);
+ struct nfs4_state_owner *sp = NULL;
+ struct nfs4_state *state = NULL;
+ int open_flags = flags & (FMODE_READ|FMODE_WRITE);
+ int mask = 0;
+ int err;
+
+ /* Protect against reboot recovery - NOTE ORDER! */
+ down_read(&clp->cl_sem);
+ /* Protect against delegation recall */
+ down_read(&nfsi->rwsem);
+ delegation = NFS_I(inode)->delegation;
+ err = -ENOENT;
+ if (delegation == NULL || (delegation->type & open_flags) != open_flags)
+ goto out_err;
+ err = -ENOMEM;
+ if (!(sp = nfs4_get_state_owner(server, cred))) {
+ dprintk("%s: nfs4_get_state_owner failed!\n", __FUNCTION__);
+ goto out_err;
+ }
+ down(&sp->so_sema);
+ state = nfs4_get_open_state(inode, sp);
+ if (state == NULL)
+ goto out_err;
+
+ err = -ENOENT;
+ if ((state->state & open_flags) == open_flags) {
+ spin_lock(&inode->i_lock);
+ if (open_flags & FMODE_READ)
+ state->nreaders++;
+ if (open_flags & FMODE_WRITE)
+ state->nwriters++;
+ spin_unlock(&inode->i_lock);
+ goto out_ok;
+ } else if (state->state != 0)
+ goto out_err;
+
+ lock_kernel();
+ err = _nfs4_do_access(inode, cred, mask);
+ unlock_kernel();
+ if (err != 0)
+ goto out_err;
+ spin_lock(&inode->i_lock);
+ memcpy(state->stateid.data, delegation->stateid.data,
+ sizeof(state->stateid.data));
+ state->state |= open_flags;
+ if (open_flags & FMODE_READ)
+ state->nreaders++;
+ if (open_flags & FMODE_WRITE)
+ state->nwriters++;
+ set_bit(NFS_DELEGATED_STATE, &state->flags);
+ spin_unlock(&inode->i_lock);
+out_ok:
+ up(&sp->so_sema);
+ nfs4_put_state_owner(sp);
+ up_read(&nfsi->rwsem);
+ up_read(&clp->cl_sem);
+ igrab(inode);
+ *res = state;
+ return 0;
+out_err:
+ if (sp != NULL) {
+ if (state != NULL)
+ nfs4_put_open_state(state);
+ up(&sp->so_sema);
+ nfs4_put_state_owner(sp);
+ }
+ up_read(&nfsi->rwsem);
+ up_read(&clp->cl_sem);
+ return err;
+}
+
+static struct nfs4_state *nfs4_open_delegated(struct inode *inode, int flags, struct rpc_cred *cred)
+{
+ struct nfs4_exception exception = { };
+ struct nfs4_state *res;
+ int err;
+
+ do {
+ err = _nfs4_open_delegated(inode, flags, cred, &res);
+ if (err == 0)
+ break;
+ res = ERR_PTR(nfs4_handle_exception(NFS_SERVER(inode),
+ err, &exception));
+ } while (exception.retry);
+ return res;
+}
+