client.c

linux 内核源代码

 * Create a general RPC client
 */
static int nfs_init_server_rpcclient(struct nfs_server *server, rpc_authflavor_t pseudoflavour)
{
	struct nfs_client *clp = server->nfs_client;

	server->client = rpc_clone_client(clp->cl_rpcclient);
	if (IS_ERR(server->client)) {
		dprintk("%s: couldn't create rpc_client!\n", __FUNCTION__);
		return PTR_ERR(server->client);
	}

	if (pseudoflavour != clp->cl_rpcclient->cl_auth->au_flavor) {
		struct rpc_auth *auth;

		auth = rpcauth_create(pseudoflavour, server->client);
		if (IS_ERR(auth)) {
			dprintk("%s: couldn't create credcache!\n", __FUNCTION__);
			return PTR_ERR(auth);
		}
	}
	server->client->cl_softrtry = 0;
	if (server->flags & NFS_MOUNT_SOFT)
		server->client->cl_softrtry = 1;

	server->client->cl_intr = 0;
	if (server->flags & NFS4_MOUNT_INTR)
		server->client->cl_intr = 1;

	return 0;
}

/*
 * Initialise an NFS2 or NFS3 client
 */
static int nfs_init_client(struct nfs_client *clp,
			   const struct nfs_parsed_mount_data *data)
{
	int error;

	if (clp->cl_cons_state == NFS_CS_READY) {
		/* the client is already initialised */
		dprintk("<-- nfs_init_client() = 0 [already %p]\n", clp);
		return 0;
	}

	/* Check NFS protocol revision and initialize RPC op vector */
	clp->rpc_ops = &nfs_v2_clientops;
#ifdef CONFIG_NFS_V3
	if (clp->cl_nfsversion == 3)
		clp->rpc_ops = &nfs_v3_clientops;
#endif
	/*
	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
	 * - RFC 2623, sec 2.3.2
	 */
	error = nfs_create_rpc_client(clp, data->nfs_server.protocol,
				data->timeo, data->retrans, RPC_AUTH_UNIX, 0);
	if (error < 0)
		goto error;
	nfs_mark_client_ready(clp, NFS_CS_READY);
	return 0;

error:
	nfs_mark_client_ready(clp, error);
	dprintk("<-- nfs_init_client() = xerror %d\n", error);
	return error;
}

/*
 * Create a version 2 or 3 client
 */
static int nfs_init_server(struct nfs_server *server,
			   const struct nfs_parsed_mount_data *data)
{
	struct nfs_client *clp;
	int error, nfsvers = 2;

	dprintk("--> nfs_init_server()\n");

#ifdef CONFIG_NFS_V3
	if (data->flags & NFS_MOUNT_VER3)
		nfsvers = 3;
#endif

	/* Allocate or find a client reference we can use */
	clp = nfs_get_client(data->nfs_server.hostname,
				&data->nfs_server.address, nfsvers);
	if (IS_ERR(clp)) {
		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
		return PTR_ERR(clp);
	}

	error = nfs_init_client(clp, data);
	if (error < 0)
		goto error;

	server->nfs_client = clp;

	/* Initialise the client representation from the mount data */
	server->flags = data->flags & NFS_MOUNT_FLAGMASK;

	if (data->rsize)
		server->rsize = nfs_block_size(data->rsize, NULL);
	if (data->wsize)
		server->wsize = nfs_block_size(data->wsize, NULL);

	server->acregmin = data->acregmin * HZ;
	server->acregmax = data->acregmax * HZ;
	server->acdirmin = data->acdirmin * HZ;
	server->acdirmax = data->acdirmax * HZ;

	/* Start lockd here, before we might error out */
	error = nfs_start_lockd(server);
	if (error < 0)
		goto error;

	error = nfs_init_server_rpcclient(server, data->auth_flavors[0]);
	if (error < 0)
		goto error;

	server->namelen  = data->namlen;
	/* Create a client RPC handle for the NFSv3 ACL management interface */
	nfs_init_server_aclclient(server);
	dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
	return 0;

error:
	server->nfs_client = NULL;
	nfs_put_client(clp);
	dprintk("<-- nfs_init_server() = xerror %d\n", error);
	return error;
}

/*
 * Load up the server record from information gained in an fsinfo record
 */
static void nfs_server_set_fsinfo(struct nfs_server *server, struct nfs_fsinfo *fsinfo)
{
	unsigned long max_rpc_payload;

	/* Work out a lot of parameters */
	if (server->rsize == 0)
		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
	if (server->wsize == 0)
		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);

	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);

	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
	if (server->rsize > max_rpc_payload)
		server->rsize = max_rpc_payload;
	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
		server->rsize = NFS_MAX_FILE_IO_SIZE;
	server->rpages = (server->rsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;

	server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;

	if (server->wsize > max_rpc_payload)
		server->wsize = max_rpc_payload;
	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
		server->wsize = NFS_MAX_FILE_IO_SIZE;
	server->wpages = (server->wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);

	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
	if (server->dtsize > PAGE_CACHE_SIZE)
		server->dtsize = PAGE_CACHE_SIZE;
	if (server->dtsize > server->rsize)
		server->dtsize = server->rsize;

	if (server->flags & NFS_MOUNT_NOAC) {
		server->acregmin = server->acregmax = 0;
		server->acdirmin = server->acdirmax = 0;
	}

	server->maxfilesize = fsinfo->maxfilesize;

	/* We're airborne Set socket buffersize */
	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
}

/*
 * Probe filesystem information, including the FSID on v2/v3
 */
static int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
{
	struct nfs_fsinfo fsinfo;
	struct nfs_client *clp = server->nfs_client;
	int error;

	dprintk("--> nfs_probe_fsinfo()\n");

	if (clp->rpc_ops->set_capabilities != NULL) {
		error = clp->rpc_ops->set_capabilities(server, mntfh);
		if (error < 0)
			goto out_error;
	}

	fsinfo.fattr = fattr;
	nfs_fattr_init(fattr);
	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
	if (error < 0)
		goto out_error;

	nfs_server_set_fsinfo(server, &fsinfo);
	error = bdi_init(&server->backing_dev_info);
	if (error)
		goto out_error;


	/* Get some general file system info */
	if (server->namelen == 0) {
		struct nfs_pathconf pathinfo;

		pathinfo.fattr = fattr;
		nfs_fattr_init(fattr);

		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
			server->namelen = pathinfo.max_namelen;
	}

	dprintk("<-- nfs_probe_fsinfo() = 0\n");
	return 0;

out_error:
	dprintk("nfs_probe_fsinfo: error = %d\n", -error);
	return error;
}

/*
 * Copy useful information when duplicating a server record
 */
static void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
{
	target->flags = source->flags;
	target->acregmin = source->acregmin;
	target->acregmax = source->acregmax;
	target->acdirmin = source->acdirmin;
	target->acdirmax = source->acdirmax;
	target->caps = source->caps;
}

/*
 * Allocate and initialise a server record
 */
static struct nfs_server *nfs_alloc_server(void)
{
	struct nfs_server *server;

	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
	if (!server)
		return NULL;

	server->client = server->client_acl = ERR_PTR(-EINVAL);

	/* Zero out the NFS state stuff */
	INIT_LIST_HEAD(&server->client_link);
	INIT_LIST_HEAD(&server->master_link);

	server->io_stats = nfs_alloc_iostats();
	if (!server->io_stats) {
		kfree(server);
		return NULL;
	}

	return server;
}

/*
 * Free up a server record
 */
void nfs_free_server(struct nfs_server *server)
{
	dprintk("--> nfs_free_server()\n");

	spin_lock(&nfs_client_lock);
	list_del(&server->client_link);
	list_del(&server->master_link);
	spin_unlock(&nfs_client_lock);

	if (server->destroy != NULL)
		server->destroy(server);

	if (!IS_ERR(server->client_acl))
		rpc_shutdown_client(server->client_acl);
	if (!IS_ERR(server->client))
		rpc_shutdown_client(server->client);

	nfs_put_client(server->nfs_client);

	nfs_free_iostats(server->io_stats);
	bdi_destroy(&server->backing_dev_info);
	kfree(server);
	nfs_release_automount_timer();
	dprintk("<-- nfs_free_server()\n");
}

/*
 * Create a version 2 or 3 volume record
 * - keyed on server and FSID
 */
struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
				     struct nfs_fh *mntfh)
{
	struct nfs_server *server;
	struct nfs_fattr fattr;
	int error;

	server = nfs_alloc_server();
	if (!server)
		return ERR_PTR(-ENOMEM);

	/* Get a client representation */
	error = nfs_init_server(server, data);
	if (error < 0)
		goto error;

	BUG_ON(!server->nfs_client);
	BUG_ON(!server->nfs_client->rpc_ops);
	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);

	/* Probe the root fh to retrieve its FSID */
	error = nfs_probe_fsinfo(server, mntfh, &fattr);
	if (error < 0)
		goto error;
	if (server->nfs_client->rpc_ops->version == 3) {
		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
			server->namelen = NFS3_MAXNAMLEN;
		if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
			server->caps |= NFS_CAP_READDIRPLUS;
	} else {
		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
			server->namelen = NFS2_MAXNAMLEN;
	}

	if (!(fattr.valid & NFS_ATTR_FATTR)) {
		error = server->nfs_client->rpc_ops->getattr(server, mntfh, &fattr);
		if (error < 0) {
			dprintk("nfs_create_server: getattr error = %d\n", -error);
			goto error;
		}
	}
	memcpy(&server->fsid, &fattr.fsid, sizeof(server->fsid));

	dprintk("Server FSID: %llx:%llx\n",
		(unsigned long long) server->fsid.major,
		(unsigned long long) server->fsid.minor);

	BUG_ON(!server->nfs_client);
	BUG_ON(!server->nfs_client->rpc_ops);
	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);

	spin_lock(&nfs_client_lock);
	list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
	list_add_tail(&server->master_link, &nfs_volume_list);
	spin_unlock(&nfs_client_lock);

	server->mount_time = jiffies;
	return server;

error:
	nfs_free_server(server);
	return ERR_PTR(error);
}

#ifdef CONFIG_NFS_V4
/*
 * Initialise an NFS4 client record
 */
static int nfs4_init_client(struct nfs_client *clp,
		int proto, int timeo, int retrans,
		const char *ip_addr,
		rpc_authflavor_t authflavour)
{
	int error;

	if (clp->cl_cons_state == NFS_CS_READY) {
		/* the client is initialised already */
		dprintk("<-- nfs4_init_client() = 0 [already %p]\n", clp);
		return 0;
	}

	/* Check NFS protocol revision and initialize RPC op vector */
	clp->rpc_ops = &nfs_v4_clientops;

	error = nfs_create_rpc_client(clp, proto, timeo, retrans, authflavour,
					RPC_CLNT_CREATE_DISCRTRY);
	if (error < 0)
		goto error;
	memcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));

	error = nfs_idmap_new(clp);
	if (error < 0) {
		dprintk("%s: failed to create idmapper. Error = %d\n",
			__FUNCTION__, error);
		goto error;
	}
	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);

	nfs_mark_client_ready(clp, NFS_CS_READY);
	return 0;

error:
	nfs_mark_client_ready(clp, error);
	dprintk("<-- nfs4_init_client() = xerror %d\n", error);
	return error;
}

/*
 * Set up an NFS4 client
 */
static int nfs4_set_client(struct nfs_server *server,
		const char *hostname, const struct sockaddr_in *addr,
		const char *ip_addr,
		rpc_authflavor_t authflavour,
		int proto, int timeo, int retrans)
{
	struct nfs_client *clp;
	int error;

	dprintk("--> nfs4_set_client()\n");

	/* Allocate or find a client reference we can use */
	clp = nfs_get_client(hostname, addr, 4);
	if (IS_ERR(clp)) {
		error = PTR_ERR(clp);
		goto error;
	}
	error = nfs4_init_client(clp, proto, timeo, retrans, ip_addr, authflavour);
	if (error < 0)
		goto error_put;

	server->nfs_client = clp;
	dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
	return 0;

error_put:
	nfs_put_client(clp);
error:
	dprintk("<-- nfs4_set_client() = xerror %d\n", error);
	return error;
}

/*
 * Create a version 4 volume record
 */
static int nfs4_init_server(struct nfs_server *server,
		const struct nfs_parsed_mount_data *data)
{
	int error;

	dprintk("--> nfs4_init_server()\n");

	/* Initialise the client representation from the mount data */
	server->flags = data->flags & NFS_MOUNT_FLAGMASK;
	server->caps |= NFS_CAP_ATOMIC_OPEN;

	if (data->rsize)
		server->rsize = nfs_block_size(data->rsize, NULL);
	if (data->wsize)
		server->wsize = nfs_block_size(data->wsize, NULL);

	server->acregmin = data->acregmin * HZ;
	server->acregmax = data->acregmax * HZ;