C++ rpc_call_sync函数代码示例

static int
nfs3_proc_pathconf(struct nfs_server *server, struct nfs_fh *fhandle,
		   struct nfs_pathconf *info)
{
	struct rpc_message msg = {
		.rpc_proc	= &nfs3_procedures[NFS3PROC_PATHCONF],
		.rpc_argp	= fhandle,
		.rpc_resp	= info,
	};
	int	status;

	dprintk("NFS call  pathconf\n");
	nfs_fattr_init(info->fattr);
	status = rpc_call_sync(server->client, &msg, 0);
	dprintk("NFS reply pathconf: %d\n", status);
	return status;
}

/*
 * One function for each procedure in the NFS protocol.
 */
static int
nfs3_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle,
		struct nfs_fattr *fattr, struct nfs4_label *label)
{
	struct rpc_message msg = {
		.rpc_proc	= &nfs3_procedures[NFS3PROC_GETATTR],
		.rpc_argp	= fhandle,
		.rpc_resp	= fattr,
	};
	int	status;

	dprintk("NFS call  getattr\n");
	nfs_fattr_init(fattr);
	status = rpc_call_sync(server->client, &msg, 0);
	dprintk("NFS reply getattr: %d\n", status);
	return status;
}

static int
nfs3_proc_read(struct inode *inode, struct rpc_cred *cred,
	       struct nfs_fattr *fattr, int flags,
	       loff_t offset, unsigned int count, void *buffer, int *eofp)
{
	struct nfs_readargs	arg = { NFS_FH(inode), offset, count, 1,
					{{buffer, count}, {0,0}, {0,0}, {0,0},
					 {0,0}, {0,0}, {0,0}, {0,0}} };
	struct nfs_readres	res = { fattr, count, 0 };
	struct rpc_message	msg = { NFS3PROC_READ, &arg, &res, cred };
	int			status;

	dprintk("NFS call  read %d @ %Ld\n", count, (long long)offset);
	fattr->valid = 0;
	status = rpc_call_sync(NFS_CLIENT(inode), &msg, flags);
	dprintk("NFS reply read: %d\n", status);
	*eofp = res.eof;
	return status;
}

static int do_probe_callback(void *data)
{
	struct nfs4_client *clp = data;
	struct nfs4_callback *cb = &clp->cl_callback;
	struct rpc_message msg = {
		.rpc_proc       = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL],
		.rpc_argp       = clp,
	};
	int status;

	status = rpc_call_sync(cb->cb_client, &msg, RPC_TASK_SOFT);

	if (status) {
		rpc_shutdown_client(cb->cb_client);
		cb->cb_client = NULL;
	} else
		atomic_set(&cb->cb_set, 1);
	put_nfs4_client(clp);
	return 0;
}

static int
nfs_proc_remove(struct inode *dir, struct qstr *name)
{
	struct nfs_removeargs arg = {
		.fh = NFS_FH(dir),
		.name = *name,
	};
	struct rpc_message msg = { 
		.rpc_proc = &nfs_procedures[NFSPROC_REMOVE],
		.rpc_argp = &arg,
	};
	int			status;

	dprintk("NFS call  remove %s\n", name->name);
	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
	nfs_mark_for_revalidate(dir);

	dprintk("NFS reply remove: %d\n", status);
	return status;
}

static inline int
nfs_direct_commit_rpc(struct inode *inode, loff_t offset, size_t count,
	struct nfs_writeverf *verf)
{
	int result;
	struct nfs_fattr fattr;
	struct nfs_writeargs	arg = { NFS_FH(inode), offset, count, 0, 0,
					NULL };
	struct nfs_writeres	res = { &fattr, verf, 0 };
	struct rpc_message	msg = { NFS3PROC_COMMIT, &arg, &res, NULL };

	fattr.valid = 0;

	lock_kernel();
	result = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
	nfs_write_attributes(inode, &fattr);
	unlock_kernel();

	return result;
}

/* Returns 0 on success
  * err_no on failure
  */
static int vsnfs_proc_null(struct vsnfs_server *server, int input, int *output)
{
	int status;
	struct vsnfs_nullargs arg = {
		.dummy = input,
	};
	struct vsnfs_nullres res;

	struct rpc_message msg = {
		.rpc_proc = &vsnfs_procedures[VSNFSPROC_NULL],
		.rpc_argp = &arg,
		.rpc_resp = &res,
	};

	status = rpc_call_sync(server->cl_rpcclient, &msg, 0);

	if (status == 0)
		*output = res.dummy;

	return status;
}

static int
nfs3_proc_remove(struct inode *dir, struct qstr *name)
{
	struct nfs_removeargs arg = {
		.fh = NFS_FH(dir),
		.name.len = name->len,
		.name.name = name->name,
	};
	struct nfs_removeres res;
	struct rpc_message msg = {
		.rpc_proc = &nfs3_procedures[NFS3PROC_REMOVE],
		.rpc_argp = &arg,
		.rpc_resp = &res,
	};
	int status = -ENOMEM;

	dprintk("NFS call  remove %s\n", name->name);
	res.dir_attr = nfs_alloc_fattr();
	if (res.dir_attr == NULL)
		goto out;

	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
	nfs_post_op_update_inode(dir, res.dir_attr);
	nfs_free_fattr(res.dir_attr);
out:
	dprintk("NFS reply remove: %d\n", status);
	return status;
}

static void
nfs3_proc_unlink_setup(struct rpc_message *msg, struct inode *dir)
{
	msg->rpc_proc = &nfs3_procedures[NFS3PROC_REMOVE];
}

static void nfs3_proc_unlink_rpc_prepare(struct rpc_task *task, struct nfs_unlinkdata *data)
{
	rpc_call_start(task);
}

static int
vsnfs_proc_readdir(struct dentry *dentry, struct page *page,
		   unsigned int count)
{
	int status;
	struct inode *dir = dentry->d_inode;
	struct vsnfs_readdirargs arg = {
		.fh = VSNFS_FH(dir),
		.count = count,
		.pages = &page,
	};
	struct rpc_message msg = {
		.rpc_proc = &vsnfs_procedures[VSNFSPROC_READDIR],
		.rpc_argp = &arg,
		.rpc_cred = NULL,
	};

	status = rpc_call_sync(VSNFS_CLIENT(dir), &msg, 0);

	printk("VSNFS reply readdir: %d\n", status);
	return status;
}

static int
nfs_proc_rename(struct inode *old_dir, struct qstr *old_name,
		struct inode *new_dir, struct qstr *new_name)
{
	struct nfs_renameargs	arg = {
		.old_dir	= NFS_FH(old_dir),
		.old_name	= old_name,
		.new_dir	= NFS_FH(new_dir),
		.new_name	= new_name,
	};
	struct rpc_message msg = {
		.rpc_proc	= &nfs_procedures[NFSPROC_RENAME],
		.rpc_argp	= &arg,
	};
	int			status;

	dprintk("NFS call  rename %s -> %s\n", old_name->name, new_name->name);
	status = rpc_call_sync(NFS_CLIENT(old_dir), &msg, 0);
	nfs_mark_for_revalidate(old_dir);
	nfs_mark_for_revalidate(new_dir);
	dprintk("NFS reply rename: %d\n", status);
	return status;
}

static int
nfs3_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
			struct iattr *sattr)
{
	struct inode *inode = dentry->d_inode;
	struct nfs3_sattrargs	arg = {
		.fh		= NFS_FH(inode),
		.sattr		= sattr,
	};
	struct rpc_message msg = {
		.rpc_proc	= &nfs3_procedures[NFS3PROC_SETATTR],
		.rpc_argp	= &arg,
		.rpc_resp	= fattr,
	};
	int	status;

	dprintk("NFS call  setattr\n");
	nfs_fattr_init(fattr);
	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
	if (status == 0)
		nfs_setattr_update_inode(inode, sattr);
	dprintk("NFS reply setattr: %d\n", status);
	return status;
}

static int
nfs3_proc_lookup(struct inode *dir, struct qstr *name,
		 struct nfs_fh *fhandle, struct nfs_fattr *fattr)
{
	struct nfs_fattr	dir_attr;
	struct nfs3_diropargs	arg = {
		.fh		= NFS_FH(dir),
		.name		= name->name,
		.len		= name->len
	};
	struct nfs3_diropres	res = {
		.dir_attr	= &dir_attr,
		.fh		= fhandle,
		.fattr		= fattr
	};
	struct rpc_message msg = {
		.rpc_proc	= &nfs3_procedures[NFS3PROC_LOOKUP],
		.rpc_argp	= &arg,
		.rpc_resp	= &res,
	};
	int			status;

	dprintk("NFS call  lookup %s\n", name->name);
	nfs_fattr_init(&dir_attr);
	nfs_fattr_init(fattr);
	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
	if (status >= 0 && !(fattr->valid & NFS_ATTR_FATTR)) {
		msg.rpc_proc = &nfs3_procedures[NFS3PROC_GETATTR];
		msg.rpc_argp = fhandle;
		msg.rpc_resp = fattr;
		status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
	}
	dprintk("NFS reply lookup: %d\n", status);
	if (status >= 0)
		status = nfs_refresh_inode(dir, &dir_attr);
	return status;
}

static int nfs3_proc_access(struct inode *inode, struct nfs_access_entry *entry)
{
	struct nfs_fattr	fattr;
	struct nfs3_accessargs	arg = {
		.fh		= NFS_FH(inode),
	};
	struct nfs3_accessres	res = {
		.fattr		= &fattr,
	};
	struct rpc_message msg = {
		.rpc_proc	= &nfs3_procedures[NFS3PROC_ACCESS],
		.rpc_argp	= &arg,
		.rpc_resp	= &res,
		.rpc_cred	= entry->cred,
	};
	int mode = entry->mask;
	int status;

	dprintk("NFS call  access\n");

	if (mode & MAY_READ)
		arg.access |= NFS3_ACCESS_READ;
	if (S_ISDIR(inode->i_mode)) {
		if (mode & MAY_WRITE)
			arg.access |= NFS3_ACCESS_MODIFY | NFS3_ACCESS_EXTEND | NFS3_ACCESS_DELETE;
		if (mode & MAY_EXEC)
			arg.access |= NFS3_ACCESS_LOOKUP;
	} else {
		if (mode & MAY_WRITE)
			arg.access |= NFS3_ACCESS_MODIFY | NFS3_ACCESS_EXTEND;
		if (mode & MAY_EXEC)
			arg.access |= NFS3_ACCESS_EXECUTE;
	}
	nfs_fattr_init(&fattr);
	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
	nfs_refresh_inode(inode, &fattr);
	if (status == 0) {
		entry->mask = 0;
		if (res.access & NFS3_ACCESS_READ)
			entry->mask |= MAY_READ;
		if (res.access & (NFS3_ACCESS_MODIFY | NFS3_ACCESS_EXTEND | NFS3_ACCESS_DELETE))
			entry->mask |= MAY_WRITE;
		if (res.access & (NFS3_ACCESS_LOOKUP|NFS3_ACCESS_EXECUTE))
			entry->mask |= MAY_EXEC;
	}
	dprintk("NFS reply access: %d\n", status);
	return status;
}

static int nfs3_proc_readlink(struct inode *inode, struct page *page,
		unsigned int pgbase, unsigned int pglen)
{
	struct nfs_fattr	fattr;
	struct nfs3_readlinkargs args = {
		.fh		= NFS_FH(inode),
		.pgbase		= pgbase,
		.pglen		= pglen,
		.pages		= &page
	};
	struct rpc_message msg = {
		.rpc_proc	= &nfs3_procedures[NFS3PROC_READLINK],
		.rpc_argp	= &args,
//.........这里部分代码省略.........

static int do_probe_callback(void *data)
{
	struct nfs4_client *clp = data;
	struct sockaddr_in	addr;
	struct nfs4_callback    *cb = &clp->cl_callback;
	struct rpc_timeout	timeparms = {
		.to_initval	= (NFSD_LEASE_TIME/4) * HZ,
		.to_retries	= 5,
		.to_maxval	= (NFSD_LEASE_TIME/2) * HZ,
		.to_exponential	= 1,
	};
	struct rpc_program *	program = &cb->cb_program;
	struct rpc_create_args args = {
		.protocol	= IPPROTO_TCP,
		.address	= (struct sockaddr *)&addr,
		.addrsize	= sizeof(addr),
		.timeout	= &timeparms,
		.program	= program,
		.version	= nfs_cb_version[1]->number,
		.authflavor	= RPC_AUTH_UNIX, /* XXX: need AUTH_GSS... */
		.flags		= (RPC_CLNT_CREATE_NOPING),
	};
	struct rpc_message msg = {
		.rpc_proc       = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL],
		.rpc_argp       = clp,
	};
	struct rpc_clnt *client;
	int status;

	/* Initialize address */
	memset(&addr, 0, sizeof(addr));
	addr.sin_family = AF_INET;
	addr.sin_port = htons(cb->cb_port);
	addr.sin_addr.s_addr = htonl(cb->cb_addr);

	/* Initialize rpc_program */
	program->name = "nfs4_cb";
	program->number = cb->cb_prog;
	program->nrvers = ARRAY_SIZE(nfs_cb_version);
	program->version = nfs_cb_version;
	program->stats = &cb->cb_stat;

	/* Initialize rpc_stat */
	memset(program->stats, 0, sizeof(cb->cb_stat));
	program->stats->program = program;

	/* Create RPC client */
	client = rpc_create(&args);
	if (IS_ERR(client)) {
		dprintk("NFSD: couldn't create callback client\n");
		status = PTR_ERR(client);
		goto out_err;
	}

	status = rpc_call_sync(client, &msg, RPC_TASK_SOFT);

	if (status)
		goto out_release_client;

	cb->cb_client = client;
	atomic_set(&cb->cb_set, 1);
	put_nfs4_client(clp);
	return 0;
out_release_client:
	rpc_shutdown_client(client);
out_err:
	put_nfs4_client(clp);
	dprintk("NFSD: warning: no callback path to client %.*s\n",
		(int)clp->cl_name.len, clp->cl_name.data);
	return status;
}

/*
 * Set up the callback client and put a NFSPROC4_CB_NULL on the wire...
 */
void
nfsd4_probe_callback(struct nfs4_client *clp)
{
	struct task_struct *t;

	BUG_ON(atomic_read(&clp->cl_callback.cb_set));

	/* the task holds a reference to the nfs4_client struct */
	atomic_inc(&clp->cl_count);

	t = kthread_run(do_probe_callback, clp, "nfs4_cb_probe");

	if (IS_ERR(t))
		atomic_dec(&clp->cl_count);

	return;
}

/*
 * called with dp->dl_count inc'ed.
 * nfs4_lock_state() may or may not have been called.
 */
void
nfsd4_cb_recall(struct nfs4_delegation *dp)
{
//.........这里部分代码省略.........

static int
nfs_proc_remove(struct inode *dir, struct qstr *name)
{
	struct nfs_removeargs arg = {
		.fh = NFS_FH(dir),
		.name.len = name->len,
		.name.name = name->name,
	};
	struct rpc_message msg = { 
		.rpc_proc = &nfs_procedures[NFSPROC_REMOVE],
		.rpc_argp = &arg,
	};
	int			status;

	dprintk("NFS call  remove %s\n", name->name);
	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
	nfs_mark_for_revalidate(dir);

	dprintk("NFS reply remove: %d\n", status);
	return status;
}

static void
nfs_proc_unlink_setup(struct rpc_message *msg, struct inode *dir)
{
	msg->rpc_proc = &nfs_procedures[NFSPROC_REMOVE];
}

static int nfs_proc_unlink_done(struct rpc_task *task, struct inode *dir)
{
	if (nfs_async_handle_expired_key(task))
		return 0;
	nfs_mark_for_revalidate(dir);
	return 1;
}

static void
nfs_proc_rename_setup(struct rpc_message *msg, struct inode *dir)
{
	msg->rpc_proc = &nfs_procedures[NFSPROC_RENAME];
}

static int
nfs_proc_rename_done(struct rpc_task *task, struct inode *old_dir,
		     struct inode *new_dir)
{
	if (nfs_async_handle_expired_key(task))
		return 0;
	nfs_mark_for_revalidate(old_dir);
	nfs_mark_for_revalidate(new_dir);
	return 1;
}

static int
nfs_proc_rename(struct inode *old_dir, struct qstr *old_name,
		struct inode *new_dir, struct qstr *new_name)
{
	struct nfs_renameargs	arg = {
		.old_dir	= NFS_FH(old_dir),
		.old_name	= old_name,
		.new_dir	= NFS_FH(new_dir),
		.new_name	= new_name,
	};
	struct rpc_message msg = {
		.rpc_proc	= &nfs_procedures[NFSPROC_RENAME],
		.rpc_argp	= &arg,
	};
	int			status;

	dprintk("NFS call  rename %s -> %s\n", old_name->name, new_name->name);
	status = rpc_call_sync(NFS_CLIENT(old_dir), &msg, 0);
	nfs_mark_for_revalidate(old_dir);
	nfs_mark_for_revalidate(new_dir);
	dprintk("NFS reply rename: %d\n", status);
	return status;
}

static int
nfs_proc_link(struct inode *inode, struct inode *dir, struct qstr *name)
{
	struct nfs_linkargs	arg = {
		.fromfh		= NFS_FH(inode),
		.tofh		= NFS_FH(dir),
		.toname		= name->name,
		.tolen		= name->len
	};
	struct rpc_message msg = {
		.rpc_proc	= &nfs_procedures[NFSPROC_LINK],
		.rpc_argp	= &arg,
	};
	int			status;

	dprintk("NFS call  link %s\n", name->name);
	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
	nfs_mark_for_revalidate(inode);
	nfs_mark_for_revalidate(dir);
	dprintk("NFS reply link: %d\n", status);
	return status;
}

//.........这里部分代码省略.........

static int
nfs_proc_lookup(struct inode *dir, struct qstr *name,
		struct nfs_fh *fhandle, struct nfs_fattr *fattr,
		struct nfs4_label *label)
{
	struct nfs_diropargs	arg = {
		.fh		= NFS_FH(dir),
		.name		= name->name,
		.len		= name->len
	};
	struct nfs_diropok	res = {
		.fh		= fhandle,
		.fattr		= fattr
	};
	struct rpc_message msg = {
		.rpc_proc	= &nfs_procedures[NFSPROC_LOOKUP],
		.rpc_argp	= &arg,
		.rpc_resp	= &res,
	};
	int			status;

	dprintk("NFS call  lookup %s\n", name->name);
	nfs_fattr_init(fattr);
	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
	dprintk("NFS reply lookup: %d\n", status);
	return status;
}

static int nfs_proc_readlink(struct inode *inode, struct page *page,
		unsigned int pgbase, unsigned int pglen)
{
	struct nfs_readlinkargs	args = {
		.fh		= NFS_FH(inode),
		.pgbase		= pgbase,
		.pglen		= pglen,
		.pages		= &page
	};
	struct rpc_message msg = {
		.rpc_proc	= &nfs_procedures[NFSPROC_READLINK],
		.rpc_argp	= &args,
	};
	int			status;

	dprintk("NFS call  readlink\n");
	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
	dprintk("NFS reply readlink: %d\n", status);
	return status;
}

struct nfs_createdata {
	struct nfs_createargs arg;
	struct nfs_diropok res;
	struct nfs_fh fhandle;
	struct nfs_fattr fattr;
};

static struct nfs_createdata *nfs_alloc_createdata(struct inode *dir,
		struct dentry *dentry, struct iattr *sattr)
{
	struct nfs_createdata *data;

	data = kmalloc(sizeof(*data), GFP_KERNEL);

	if (data != NULL) {
		data->arg.fh = NFS_FH(dir);
		data->arg.name = dentry->d_name.name;
		data->arg.len = dentry->d_name.len;
		data->arg.sattr = sattr;
		nfs_fattr_init(&data->fattr);
		data->fhandle.size = 0;
		data->res.fh = &data->fhandle;
		data->res.fattr = &data->fattr;
	}
	return data;
};

static void nfs_free_createdata(const struct nfs_createdata *data)
{
	kfree(data);
}