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-rw-r--r--net/sunrpc/clnt.c1085
1 files changed, 1085 insertions, 0 deletions
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
new file mode 100644
index 00000000000..02bc029d46f
--- /dev/null
+++ b/net/sunrpc/clnt.c
@@ -0,0 +1,1085 @@
+/*
+ * linux/net/sunrpc/rpcclnt.c
+ *
+ * This file contains the high-level RPC interface.
+ * It is modeled as a finite state machine to support both synchronous
+ * and asynchronous requests.
+ *
+ * - RPC header generation and argument serialization.
+ * - Credential refresh.
+ * - TCP connect handling.
+ * - Retry of operation when it is suspected the operation failed because
+ * of uid squashing on the server, or when the credentials were stale
+ * and need to be refreshed, or when a packet was damaged in transit.
+ * This may be have to be moved to the VFS layer.
+ *
+ * NB: BSD uses a more intelligent approach to guessing when a request
+ * or reply has been lost by keeping the RTO estimate for each procedure.
+ * We currently make do with a constant timeout value.
+ *
+ * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
+ * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
+ */
+
+#include <asm/system.h>
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/in.h>
+#include <linux/utsname.h>
+
+#include <linux/sunrpc/clnt.h>
+#include <linux/workqueue.h>
+#include <linux/sunrpc/rpc_pipe_fs.h>
+
+#include <linux/nfs.h>
+
+
+#define RPC_SLACK_SPACE (1024) /* total overkill */
+
+#ifdef RPC_DEBUG
+# define RPCDBG_FACILITY RPCDBG_CALL
+#endif
+
+static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
+
+
+static void call_start(struct rpc_task *task);
+static void call_reserve(struct rpc_task *task);
+static void call_reserveresult(struct rpc_task *task);
+static void call_allocate(struct rpc_task *task);
+static void call_encode(struct rpc_task *task);
+static void call_decode(struct rpc_task *task);
+static void call_bind(struct rpc_task *task);
+static void call_transmit(struct rpc_task *task);
+static void call_status(struct rpc_task *task);
+static void call_refresh(struct rpc_task *task);
+static void call_refreshresult(struct rpc_task *task);
+static void call_timeout(struct rpc_task *task);
+static void call_connect(struct rpc_task *task);
+static void call_connect_status(struct rpc_task *task);
+static u32 * call_header(struct rpc_task *task);
+static u32 * call_verify(struct rpc_task *task);
+
+
+static int
+rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
+{
+ static uint32_t clntid;
+ int error;
+
+ if (dir_name == NULL)
+ return 0;
+ for (;;) {
+ snprintf(clnt->cl_pathname, sizeof(clnt->cl_pathname),
+ "%s/clnt%x", dir_name,
+ (unsigned int)clntid++);
+ clnt->cl_pathname[sizeof(clnt->cl_pathname) - 1] = '\0';
+ clnt->cl_dentry = rpc_mkdir(clnt->cl_pathname, clnt);
+ if (!IS_ERR(clnt->cl_dentry))
+ return 0;
+ error = PTR_ERR(clnt->cl_dentry);
+ if (error != -EEXIST) {
+ printk(KERN_INFO "RPC: Couldn't create pipefs entry %s, error %d\n",
+ clnt->cl_pathname, error);
+ return error;
+ }
+ }
+}
+
+/*
+ * Create an RPC client
+ * FIXME: This should also take a flags argument (as in task->tk_flags).
+ * It's called (among others) from pmap_create_client, which may in
+ * turn be called by an async task. In this case, rpciod should not be
+ * made to sleep too long.
+ */
+struct rpc_clnt *
+rpc_create_client(struct rpc_xprt *xprt, char *servname,
+ struct rpc_program *program, u32 vers,
+ rpc_authflavor_t flavor)
+{
+ struct rpc_version *version;
+ struct rpc_clnt *clnt = NULL;
+ int err;
+ int len;
+
+ dprintk("RPC: creating %s client for %s (xprt %p)\n",
+ program->name, servname, xprt);
+
+ err = -EINVAL;
+ if (!xprt)
+ goto out_err;
+ if (vers >= program->nrvers || !(version = program->version[vers]))
+ goto out_err;
+
+ err = -ENOMEM;
+ clnt = (struct rpc_clnt *) kmalloc(sizeof(*clnt), GFP_KERNEL);
+ if (!clnt)
+ goto out_err;
+ memset(clnt, 0, sizeof(*clnt));
+ atomic_set(&clnt->cl_users, 0);
+ atomic_set(&clnt->cl_count, 1);
+ clnt->cl_parent = clnt;
+
+ clnt->cl_server = clnt->cl_inline_name;
+ len = strlen(servname) + 1;
+ if (len > sizeof(clnt->cl_inline_name)) {
+ char *buf = kmalloc(len, GFP_KERNEL);
+ if (buf != 0)
+ clnt->cl_server = buf;
+ else
+ len = sizeof(clnt->cl_inline_name);
+ }
+ strlcpy(clnt->cl_server, servname, len);
+
+ clnt->cl_xprt = xprt;
+ clnt->cl_procinfo = version->procs;
+ clnt->cl_maxproc = version->nrprocs;
+ clnt->cl_protname = program->name;
+ clnt->cl_pmap = &clnt->cl_pmap_default;
+ clnt->cl_port = xprt->addr.sin_port;
+ clnt->cl_prog = program->number;
+ clnt->cl_vers = version->number;
+ clnt->cl_prot = xprt->prot;
+ clnt->cl_stats = program->stats;
+ rpc_init_wait_queue(&clnt->cl_pmap_default.pm_bindwait, "bindwait");
+
+ if (!clnt->cl_port)
+ clnt->cl_autobind = 1;
+
+ clnt->cl_rtt = &clnt->cl_rtt_default;
+ rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval);
+
+ err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
+ if (err < 0)
+ goto out_no_path;
+
+ err = -ENOMEM;
+ if (!rpcauth_create(flavor, clnt)) {
+ printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
+ flavor);
+ goto out_no_auth;
+ }
+
+ /* save the nodename */
+ clnt->cl_nodelen = strlen(system_utsname.nodename);
+ if (clnt->cl_nodelen > UNX_MAXNODENAME)
+ clnt->cl_nodelen = UNX_MAXNODENAME;
+ memcpy(clnt->cl_nodename, system_utsname.nodename, clnt->cl_nodelen);
+ return clnt;
+
+out_no_auth:
+ rpc_rmdir(clnt->cl_pathname);
+out_no_path:
+ if (clnt->cl_server != clnt->cl_inline_name)
+ kfree(clnt->cl_server);
+ kfree(clnt);
+out_err:
+ return ERR_PTR(err);
+}
+
+/*
+ * This function clones the RPC client structure. It allows us to share the
+ * same transport while varying parameters such as the authentication
+ * flavour.
+ */
+struct rpc_clnt *
+rpc_clone_client(struct rpc_clnt *clnt)
+{
+ struct rpc_clnt *new;
+
+ new = (struct rpc_clnt *)kmalloc(sizeof(*new), GFP_KERNEL);
+ if (!new)
+ goto out_no_clnt;
+ memcpy(new, clnt, sizeof(*new));
+ atomic_set(&new->cl_count, 1);
+ atomic_set(&new->cl_users, 0);
+ new->cl_parent = clnt;
+ atomic_inc(&clnt->cl_count);
+ /* Duplicate portmapper */
+ rpc_init_wait_queue(&new->cl_pmap_default.pm_bindwait, "bindwait");
+ /* Turn off autobind on clones */
+ new->cl_autobind = 0;
+ new->cl_oneshot = 0;
+ new->cl_dead = 0;
+ rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval);
+ if (new->cl_auth)
+ atomic_inc(&new->cl_auth->au_count);
+ return new;
+out_no_clnt:
+ printk(KERN_INFO "RPC: out of memory in %s\n", __FUNCTION__);
+ return ERR_PTR(-ENOMEM);
+}
+
+/*
+ * Properly shut down an RPC client, terminating all outstanding
+ * requests. Note that we must be certain that cl_oneshot and
+ * cl_dead are cleared, or else the client would be destroyed
+ * when the last task releases it.
+ */
+int
+rpc_shutdown_client(struct rpc_clnt *clnt)
+{
+ dprintk("RPC: shutting down %s client for %s, tasks=%d\n",
+ clnt->cl_protname, clnt->cl_server,
+ atomic_read(&clnt->cl_users));
+
+ while (atomic_read(&clnt->cl_users) > 0) {
+ /* Don't let rpc_release_client destroy us */
+ clnt->cl_oneshot = 0;
+ clnt->cl_dead = 0;
+ rpc_killall_tasks(clnt);
+ sleep_on_timeout(&destroy_wait, 1*HZ);
+ }
+
+ if (atomic_read(&clnt->cl_users) < 0) {
+ printk(KERN_ERR "RPC: rpc_shutdown_client clnt %p tasks=%d\n",
+ clnt, atomic_read(&clnt->cl_users));
+#ifdef RPC_DEBUG
+ rpc_show_tasks();
+#endif
+ BUG();
+ }
+
+ return rpc_destroy_client(clnt);
+}
+
+/*
+ * Delete an RPC client
+ */
+int
+rpc_destroy_client(struct rpc_clnt *clnt)
+{
+ if (!atomic_dec_and_test(&clnt->cl_count))
+ return 1;
+ BUG_ON(atomic_read(&clnt->cl_users) != 0);
+
+ dprintk("RPC: destroying %s client for %s\n",
+ clnt->cl_protname, clnt->cl_server);
+ if (clnt->cl_auth) {
+ rpcauth_destroy(clnt->cl_auth);
+ clnt->cl_auth = NULL;
+ }
+ if (clnt->cl_parent != clnt) {
+ rpc_destroy_client(clnt->cl_parent);
+ goto out_free;
+ }
+ if (clnt->cl_pathname[0])
+ rpc_rmdir(clnt->cl_pathname);
+ if (clnt->cl_xprt) {
+ xprt_destroy(clnt->cl_xprt);
+ clnt->cl_xprt = NULL;
+ }
+ if (clnt->cl_server != clnt->cl_inline_name)
+ kfree(clnt->cl_server);
+out_free:
+ kfree(clnt);
+ return 0;
+}
+
+/*
+ * Release an RPC client
+ */
+void
+rpc_release_client(struct rpc_clnt *clnt)
+{
+ dprintk("RPC: rpc_release_client(%p, %d)\n",
+ clnt, atomic_read(&clnt->cl_users));
+
+ if (!atomic_dec_and_test(&clnt->cl_users))
+ return;
+ wake_up(&destroy_wait);
+ if (clnt->cl_oneshot || clnt->cl_dead)
+ rpc_destroy_client(clnt);
+}
+
+/*
+ * Default callback for async RPC calls
+ */
+static void
+rpc_default_callback(struct rpc_task *task)
+{
+}
+
+/*
+ * Export the signal mask handling for aysnchronous code that
+ * sleeps on RPC calls
+ */
+
+void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset)
+{
+ unsigned long sigallow = sigmask(SIGKILL);
+ unsigned long irqflags;
+
+ /* Turn off various signals */
+ if (clnt->cl_intr) {
+ struct k_sigaction *action = current->sighand->action;
+ if (action[SIGINT-1].sa.sa_handler == SIG_DFL)
+ sigallow |= sigmask(SIGINT);
+ if (action[SIGQUIT-1].sa.sa_handler == SIG_DFL)
+ sigallow |= sigmask(SIGQUIT);
+ }
+ spin_lock_irqsave(&current->sighand->siglock, irqflags);
+ *oldset = current->blocked;
+ siginitsetinv(&current->blocked, sigallow & ~oldset->sig[0]);
+ recalc_sigpending();
+ spin_unlock_irqrestore(&current->sighand->siglock, irqflags);
+}
+
+void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset)
+{
+ unsigned long irqflags;
+
+ spin_lock_irqsave(&current->sighand->siglock, irqflags);
+ current->blocked = *oldset;
+ recalc_sigpending();
+ spin_unlock_irqrestore(&current->sighand->siglock, irqflags);
+}
+
+/*
+ * New rpc_call implementation
+ */
+int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
+{
+ struct rpc_task *task;
+ sigset_t oldset;
+ int status;
+
+ /* If this client is slain all further I/O fails */
+ if (clnt->cl_dead)
+ return -EIO;
+
+ BUG_ON(flags & RPC_TASK_ASYNC);
+
+ rpc_clnt_sigmask(clnt, &oldset);
+
+ status = -ENOMEM;
+ task = rpc_new_task(clnt, NULL, flags);
+ if (task == NULL)
+ goto out;
+
+ rpc_call_setup(task, msg, 0);
+
+ /* Set up the call info struct and execute the task */
+ if (task->tk_status == 0)
+ status = rpc_execute(task);
+ else {
+ status = task->tk_status;
+ rpc_release_task(task);
+ }
+
+out:
+ rpc_clnt_sigunmask(clnt, &oldset);
+
+ return status;
+}
+
+/*
+ * New rpc_call implementation
+ */
+int
+rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags,
+ rpc_action callback, void *data)
+{
+ struct rpc_task *task;
+ sigset_t oldset;
+ int status;
+
+ /* If this client is slain all further I/O fails */
+ if (clnt->cl_dead)
+ return -EIO;
+
+ flags |= RPC_TASK_ASYNC;
+
+ rpc_clnt_sigmask(clnt, &oldset);
+
+ /* Create/initialize a new RPC task */
+ if (!callback)
+ callback = rpc_default_callback;
+ status = -ENOMEM;
+ if (!(task = rpc_new_task(clnt, callback, flags)))
+ goto out;
+ task->tk_calldata = data;
+
+ rpc_call_setup(task, msg, 0);
+
+ /* Set up the call info struct and execute the task */
+ status = task->tk_status;
+ if (status == 0)
+ rpc_execute(task);
+ else
+ rpc_release_task(task);
+
+out:
+ rpc_clnt_sigunmask(clnt, &oldset);
+
+ return status;
+}
+
+
+void
+rpc_call_setup(struct rpc_task *task, struct rpc_message *msg, int flags)
+{
+ task->tk_msg = *msg;
+ task->tk_flags |= flags;
+ /* Bind the user cred */
+ if (task->tk_msg.rpc_cred != NULL)
+ rpcauth_holdcred(task);
+ else
+ rpcauth_bindcred(task);
+
+ if (task->tk_status == 0)
+ task->tk_action = call_start;
+ else
+ task->tk_action = NULL;
+}
+
+void
+rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
+{
+ struct rpc_xprt *xprt = clnt->cl_xprt;
+
+ xprt->sndsize = 0;
+ if (sndsize)
+ xprt->sndsize = sndsize + RPC_SLACK_SPACE;
+ xprt->rcvsize = 0;
+ if (rcvsize)
+ xprt->rcvsize = rcvsize + RPC_SLACK_SPACE;
+ if (xprt_connected(xprt))
+ xprt_sock_setbufsize(xprt);
+}
+
+/*
+ * Return size of largest payload RPC client can support, in bytes
+ *
+ * For stream transports, this is one RPC record fragment (see RFC
+ * 1831), as we don't support multi-record requests yet. For datagram
+ * transports, this is the size of an IP packet minus the IP, UDP, and
+ * RPC header sizes.
+ */
+size_t rpc_max_payload(struct rpc_clnt *clnt)
+{
+ return clnt->cl_xprt->max_payload;
+}
+EXPORT_SYMBOL(rpc_max_payload);
+
+/*
+ * Restart an (async) RPC call. Usually called from within the
+ * exit handler.
+ */
+void
+rpc_restart_call(struct rpc_task *task)
+{
+ if (RPC_ASSASSINATED(task))
+ return;
+
+ task->tk_action = call_start;
+}
+
+/*
+ * 0. Initial state
+ *
+ * Other FSM states can be visited zero or more times, but
+ * this state is visited exactly once for each RPC.
+ */
+static void
+call_start(struct rpc_task *task)
+{
+ struct rpc_clnt *clnt = task->tk_client;
+
+ dprintk("RPC: %4d call_start %s%d proc %d (%s)\n", task->tk_pid,
+ clnt->cl_protname, clnt->cl_vers, task->tk_msg.rpc_proc->p_proc,
+ (RPC_IS_ASYNC(task) ? "async" : "sync"));
+
+ /* Increment call count */
+ task->tk_msg.rpc_proc->p_count++;
+ clnt->cl_stats->rpccnt++;
+ task->tk_action = call_reserve;
+}
+
+/*
+ * 1. Reserve an RPC call slot
+ */
+static void
+call_reserve(struct rpc_task *task)
+{
+ dprintk("RPC: %4d call_reserve\n", task->tk_pid);
+
+ if (!rpcauth_uptodatecred(task)) {
+ task->tk_action = call_refresh;
+ return;
+ }
+
+ task->tk_status = 0;
+ task->tk_action = call_reserveresult;
+ xprt_reserve(task);
+}
+
+/*
+ * 1b. Grok the result of xprt_reserve()
+ */
+static void
+call_reserveresult(struct rpc_task *task)
+{
+ int status = task->tk_status;
+
+ dprintk("RPC: %4d call_reserveresult (status %d)\n",
+ task->tk_pid, task->tk_status);
+
+ /*
+ * After a call to xprt_reserve(), we must have either
+ * a request slot or else an error status.
+ */
+ task->tk_status = 0;
+ if (status >= 0) {
+ if (task->tk_rqstp) {
+ task->tk_action = call_allocate;
+ return;
+ }
+
+ printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
+ __FUNCTION__, status);
+ rpc_exit(task, -EIO);
+ return;
+ }
+
+ /*
+ * Even though there was an error, we may have acquired
+ * a request slot somehow. Make sure not to leak it.
+ */
+ if (task->tk_rqstp) {
+ printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
+ __FUNCTION__, status);
+ xprt_release(task);
+ }
+
+ switch (status) {
+ case -EAGAIN: /* woken up; retry */
+ task->tk_action = call_reserve;
+ return;
+ case -EIO: /* probably a shutdown */
+ break;
+ default:
+ printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
+ __FUNCTION__, status);
+ break;
+ }
+ rpc_exit(task, status);
+}
+
+/*
+ * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
+ * (Note: buffer memory is freed in rpc_task_release).
+ */
+static void
+call_allocate(struct rpc_task *task)
+{
+ unsigned int bufsiz;
+
+ dprintk("RPC: %4d call_allocate (status %d)\n",
+ task->tk_pid, task->tk_status);
+ task->tk_action = call_bind;
+ if (task->tk_buffer)
+ return;
+
+ /* FIXME: compute buffer requirements more exactly using
+ * auth->au_wslack */
+ bufsiz = task->tk_msg.rpc_proc->p_bufsiz + RPC_SLACK_SPACE;
+
+ if (rpc_malloc(task, bufsiz << 1) != NULL)
+ return;
+ printk(KERN_INFO "RPC: buffer allocation failed for task %p\n", task);
+
+ if (RPC_IS_ASYNC(task) || !(task->tk_client->cl_intr && signalled())) {
+ xprt_release(task);
+ task->tk_action = call_reserve;
+ rpc_delay(task, HZ>>4);
+ return;
+ }
+
+ rpc_exit(task, -ERESTARTSYS);
+}
+
+/*
+ * 3. Encode arguments of an RPC call
+ */
+static void
+call_encode(struct rpc_task *task)
+{
+ struct rpc_clnt *clnt = task->tk_client;
+ struct rpc_rqst *req = task->tk_rqstp;
+ struct xdr_buf *sndbuf = &req->rq_snd_buf;
+ struct xdr_buf *rcvbuf = &req->rq_rcv_buf;
+ unsigned int bufsiz;
+ kxdrproc_t encode;
+ int status;
+ u32 *p;
+
+ dprintk("RPC: %4d call_encode (status %d)\n",
+ task->tk_pid, task->tk_status);
+
+ /* Default buffer setup */
+ bufsiz = task->tk_bufsize >> 1;
+ sndbuf->head[0].iov_base = (void *)task->tk_buffer;
+ sndbuf->head[0].iov_len = bufsiz;
+ sndbuf->tail[0].iov_len = 0;
+ sndbuf->page_len = 0;
+ sndbuf->len = 0;
+ sndbuf->buflen = bufsiz;
+ rcvbuf->head[0].iov_base = (void *)((char *)task->tk_buffer + bufsiz);
+ rcvbuf->head[0].iov_len = bufsiz;
+ rcvbuf->tail[0].iov_len = 0;
+ rcvbuf->page_len = 0;
+ rcvbuf->len = 0;
+ rcvbuf->buflen = bufsiz;
+
+ /* Encode header and provided arguments */
+ encode = task->tk_msg.rpc_proc->p_encode;
+ if (!(p = call_header(task))) {
+ printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
+ rpc_exit(task, -EIO);
+ return;
+ }
+ if (encode && (status = rpcauth_wrap_req(task, encode, req, p,
+ task->tk_msg.rpc_argp)) < 0) {
+ printk(KERN_WARNING "%s: can't encode arguments: %d\n",
+ clnt->cl_protname, -status);
+ rpc_exit(task, status);
+ }
+}
+
+/*
+ * 4. Get the server port number if not yet set
+ */
+static void
+call_bind(struct rpc_task *task)
+{
+ struct rpc_clnt *clnt = task->tk_client;
+ struct rpc_xprt *xprt = clnt->cl_xprt;
+
+ dprintk("RPC: %4d call_bind xprt %p %s connected\n", task->tk_pid,
+ xprt, (xprt_connected(xprt) ? "is" : "is not"));
+
+ task->tk_action = (xprt_connected(xprt)) ? call_transmit : call_connect;
+
+ if (!clnt->cl_port) {
+ task->tk_action = call_connect;
+ task->tk_timeout = RPC_CONNECT_TIMEOUT;
+ rpc_getport(task, clnt);
+ }
+}
+
+/*
+ * 4a. Connect to the RPC server (TCP case)
+ */
+static void
+call_connect(struct rpc_task *task)
+{
+ struct rpc_clnt *clnt = task->tk_client;
+
+ dprintk("RPC: %4d call_connect status %d\n",
+ task->tk_pid, task->tk_status);
+
+ if (xprt_connected(clnt->cl_xprt)) {
+ task->tk_action = call_transmit;
+ return;
+ }
+ task->tk_action = call_connect_status;
+ if (task->tk_status < 0)
+ return;
+ xprt_connect(task);
+}
+
+/*
+ * 4b. Sort out connect result
+ */
+static void
+call_connect_status(struct rpc_task *task)
+{
+ struct rpc_clnt *clnt = task->tk_client;
+ int status = task->tk_status;
+
+ task->tk_status = 0;
+ if (status >= 0) {
+ clnt->cl_stats->netreconn++;
+ task->tk_action = call_transmit;
+ return;
+ }
+
+ /* Something failed: we may have to rebind */
+ if (clnt->cl_autobind)
+ clnt->cl_port = 0;
+ switch (status) {
+ case -ENOTCONN:
+ case -ETIMEDOUT:
+ case -EAGAIN:
+ task->tk_action = (clnt->cl_port == 0) ? call_bind : call_connect;
+ break;
+ default:
+ rpc_exit(task, -EIO);
+ }
+}
+
+/*
+ * 5. Transmit the RPC request, and wait for reply
+ */
+static void
+call_transmit(struct rpc_task *task)
+{
+ dprintk("RPC: %4d call_transmit (status %d)\n",
+ task->tk_pid, task->tk_status);
+
+ task->tk_action = call_status;
+ if (task->tk_status < 0)
+ return;
+ task->tk_status = xprt_prepare_transmit(task);
+ if (task->tk_status != 0)
+ return;
+ /* Encode here so that rpcsec_gss can use correct sequence number. */
+ if (!task->tk_rqstp->rq_bytes_sent)
+ call_encode(task);
+ if (task->tk_status < 0)
+ return;
+ xprt_transmit(task);
+ if (task->tk_status < 0)
+ return;
+ if (!task->tk_msg.rpc_proc->p_decode) {
+ task->tk_action = NULL;
+ rpc_wake_up_task(task);
+ }
+}
+
+/*
+ * 6. Sort out the RPC call status
+ */
+static void
+call_status(struct rpc_task *task)
+{
+ struct rpc_clnt *clnt = task->tk_client;
+ struct rpc_rqst *req = task->tk_rqstp;
+ int status;
+
+ if (req->rq_received > 0 && !req->rq_bytes_sent)
+ task->tk_status = req->rq_received;
+
+ dprintk("RPC: %4d call_status (status %d)\n",
+ task->tk_pid, task->tk_status);
+
+ status = task->tk_status;
+ if (status >= 0) {
+ task->tk_action = call_decode;
+ return;
+ }
+
+ task->tk_status = 0;
+ switch(status) {
+ case -ETIMEDOUT:
+ task->tk_action = call_timeout;
+ break;
+ case -ECONNREFUSED:
+ case -ENOTCONN:
+ req->rq_bytes_sent = 0;
+ if (clnt->cl_autobind)
+ clnt->cl_port = 0;
+ task->tk_action = call_bind;
+ break;
+ case -EAGAIN:
+ task->tk_action = call_transmit;
+ break;
+ case -EIO:
+ /* shutdown or soft timeout */
+ rpc_exit(task, status);
+ break;
+ default:
+ if (clnt->cl_chatty)
+ printk("%s: RPC call returned error %d\n",
+ clnt->cl_protname, -status);
+ rpc_exit(task, status);
+ break;
+ }
+}
+
+/*
+ * 6a. Handle RPC timeout
+ * We do not release the request slot, so we keep using the
+ * same XID for all retransmits.
+ */
+static void
+call_timeout(struct rpc_task *task)
+{
+ struct rpc_clnt *clnt = task->tk_client;
+
+ if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
+ dprintk("RPC: %4d call_timeout (minor)\n", task->tk_pid);
+ goto retry;
+ }
+
+ dprintk("RPC: %4d call_timeout (major)\n", task->tk_pid);
+ if (RPC_IS_SOFT(task)) {
+ if (clnt->cl_chatty)
+ printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
+ clnt->cl_protname, clnt->cl_server);
+ rpc_exit(task, -EIO);
+ return;
+ }
+
+ if (clnt->cl_chatty && !(task->tk_flags & RPC_CALL_MAJORSEEN)) {
+ task->tk_flags |= RPC_CALL_MAJORSEEN;
+ printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
+ clnt->cl_protname, clnt->cl_server);
+ }
+ if (clnt->cl_autobind)
+ clnt->cl_port = 0;
+
+retry:
+ clnt->cl_stats->rpcretrans++;
+ task->tk_action = call_bind;
+ task->tk_status = 0;
+}
+
+/*
+ * 7. Decode the RPC reply
+ */
+static void
+call_decode(struct rpc_task *task)
+{
+ struct rpc_clnt *clnt = task->tk_client;
+ struct rpc_rqst *req = task->tk_rqstp;
+ kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
+ u32 *p;
+
+ dprintk("RPC: %4d call_decode (status %d)\n",
+ task->tk_pid, task->tk_status);
+
+ if (clnt->cl_chatty && (task->tk_flags & RPC_CALL_MAJORSEEN)) {
+ printk(KERN_NOTICE "%s: server %s OK\n",
+ clnt->cl_protname, clnt->cl_server);
+ task->tk_flags &= ~RPC_CALL_MAJORSEEN;
+ }
+
+ if (task->tk_status < 12) {
+ if (!RPC_IS_SOFT(task)) {
+ task->tk_action = call_bind;
+ clnt->cl_stats->rpcretrans++;
+ goto out_retry;
+ }
+ printk(KERN_WARNING "%s: too small RPC reply size (%d bytes)\n",
+ clnt->cl_protname, task->tk_status);
+ rpc_exit(task, -EIO);
+ return;
+ }
+
+ req->rq_rcv_buf.len = req->rq_private_buf.len;
+
+ /* Check that the softirq receive buffer is valid */
+ WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
+ sizeof(req->rq_rcv_buf)) != 0);
+
+ /* Verify the RPC header */
+ if (!(p = call_verify(task))) {
+ if (task->tk_action == NULL)
+ return;
+ goto out_retry;
+ }
+
+ task->tk_action = NULL;
+
+ if (decode)
+ task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
+ task->tk_msg.rpc_resp);
+ dprintk("RPC: %4d call_decode result %d\n", task->tk_pid,
+ task->tk_status);
+ return;
+out_retry:
+ req->rq_received = req->rq_private_buf.len = 0;
+ task->tk_status = 0;
+}
+
+/*
+ * 8. Refresh the credentials if rejected by the server
+ */
+static void
+call_refresh(struct rpc_task *task)
+{
+ dprintk("RPC: %4d call_refresh\n", task->tk_pid);
+
+ xprt_release(task); /* Must do to obtain new XID */
+ task->tk_action = call_refreshresult;
+ task->tk_status = 0;
+ task->tk_client->cl_stats->rpcauthrefresh++;
+ rpcauth_refreshcred(task);
+}
+
+/*
+ * 8a. Process the results of a credential refresh
+ */
+static void
+call_refreshresult(struct rpc_task *task)
+{
+ int status = task->tk_status;
+ dprintk("RPC: %4d call_refreshresult (status %d)\n",
+ task->tk_pid, task->tk_status);
+
+ task->tk_status = 0;
+ task->tk_action = call_reserve;
+ if (status >= 0 && rpcauth_uptodatecred(task))
+ return;
+ if (status == -EACCES) {
+ rpc_exit(task, -EACCES);
+ return;
+ }
+ task->tk_action = call_refresh;
+ if (status != -ETIMEDOUT)
+ rpc_delay(task, 3*HZ);
+ return;
+}
+
+/*
+ * Call header serialization
+ */
+static u32 *
+call_header(struct rpc_task *task)
+{
+ struct rpc_clnt *clnt = task->tk_client;
+ struct rpc_xprt *xprt = clnt->cl_xprt;
+ struct rpc_rqst *req = task->tk_rqstp;
+ u32 *p = req->rq_svec[0].iov_base;
+
+ /* FIXME: check buffer size? */
+ if (xprt->stream)
+ *p++ = 0; /* fill in later */
+ *p++ = req->rq_xid; /* XID */
+ *p++ = htonl(RPC_CALL); /* CALL */
+ *p++ = htonl(RPC_VERSION); /* RPC version */
+ *p++ = htonl(clnt->cl_prog); /* program number */
+ *p++ = htonl(clnt->cl_vers); /* program version */
+ *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
+ return rpcauth_marshcred(task, p);
+}
+
+/*
+ * Reply header verification
+ */
+static u32 *
+call_verify(struct rpc_task *task)
+{
+ struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
+ int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
+ u32 *p = iov->iov_base, n;
+ int error = -EACCES;
+
+ if ((len -= 3) < 0)
+ goto out_overflow;
+ p += 1; /* skip XID */
+
+ if ((n = ntohl(*p++)) != RPC_REPLY) {
+ printk(KERN_WARNING "call_verify: not an RPC reply: %x\n", n);
+ goto out_retry;
+ }
+ if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
+ if (--len < 0)
+ goto out_overflow;
+ switch ((n = ntohl(*p++))) {
+ case RPC_AUTH_ERROR:
+ break;
+ case RPC_MISMATCH:
+ printk(KERN_WARNING "%s: RPC call version mismatch!\n", __FUNCTION__);
+ goto out_eio;
+ default:
+ printk(KERN_WARNING "%s: RPC call rejected, unknown error: %x\n", __FUNCTION__, n);
+ goto out_eio;
+ }
+ if (--len < 0)
+ goto out_overflow;
+ switch ((n = ntohl(*p++))) {
+ case RPC_AUTH_REJECTEDCRED:
+ case RPC_AUTH_REJECTEDVERF:
+ case RPCSEC_GSS_CREDPROBLEM:
+ case RPCSEC_GSS_CTXPROBLEM:
+ if (!task->tk_cred_retry)
+ break;
+ task->tk_cred_retry--;
+ dprintk("RPC: %4d call_verify: retry stale creds\n",
+ task->tk_pid);
+ rpcauth_invalcred(task);
+ task->tk_action = call_refresh;
+ return NULL;
+ case RPC_AUTH_BADCRED:
+ case RPC_AUTH_BADVERF:
+ /* possibly garbled cred/verf? */
+ if (!task->tk_garb_retry)
+ break;
+ task->tk_garb_retry--;
+ dprintk("RPC: %4d call_verify: retry garbled creds\n",
+ task->tk_pid);
+ task->tk_action = call_bind;
+ return NULL;
+ case RPC_AUTH_TOOWEAK:
+ printk(KERN_NOTICE "call_verify: server requires stronger "
+ "authentication.\n");
+ break;
+ default:
+ printk(KERN_WARNING "call_verify: unknown auth error: %x\n", n);
+ error = -EIO;
+ }
+ dprintk("RPC: %4d call_verify: call rejected %d\n",
+ task->tk_pid, n);
+ goto out_err;
+ }
+ if (!(p = rpcauth_checkverf(task, p))) {
+ printk(KERN_WARNING "call_verify: auth check failed\n");
+ goto out_retry; /* bad verifier, retry */
+ }
+ len = p - (u32 *)iov->iov_base - 1;
+ if (len < 0)
+ goto out_overflow;
+ switch ((n = ntohl(*p++))) {
+ case RPC_SUCCESS:
+ return p;
+ case RPC_PROG_UNAVAIL:
+ printk(KERN_WARNING "RPC: call_verify: program %u is unsupported by server %s\n",
+ (unsigned int)task->tk_client->cl_prog,
+ task->tk_client->cl_server);
+ goto out_eio;
+ case RPC_PROG_MISMATCH:
+ printk(KERN_WARNING "RPC: call_verify: program %u, version %u unsupported by server %s\n",
+ (unsigned int)task->tk_client->cl_prog,
+ (unsigned int)task->tk_client->cl_vers,
+ task->tk_client->cl_server);
+ goto out_eio;
+ case RPC_PROC_UNAVAIL:
+ printk(KERN_WARNING "RPC: call_verify: proc %p unsupported by program %u, version %u on server %s\n",
+ task->tk_msg.rpc_proc,
+ task->tk_client->cl_prog,
+ task->tk_client->cl_vers,
+ task->tk_client->cl_server);
+ goto out_eio;
+ case RPC_GARBAGE_ARGS:
+ dprintk("RPC: %4d %s: server saw garbage\n", task->tk_pid, __FUNCTION__);
+ break; /* retry */
+ default:
+ printk(KERN_WARNING "call_verify: server accept status: %x\n", n);
+ /* Also retry */
+ }
+
+out_retry:
+ task->tk_client->cl_stats->rpcgarbage++;
+ if (task->tk_garb_retry) {
+ task->tk_garb_retry--;
+ dprintk(KERN_WARNING "RPC %s: retrying %4d\n", __FUNCTION__, task->tk_pid);
+ task->tk_action = call_bind;
+ return NULL;
+ }
+ printk(KERN_WARNING "RPC %s: retry failed, exit EIO\n", __FUNCTION__);
+out_eio:
+ error = -EIO;
+out_err:
+ rpc_exit(task, error);
+ return NULL;
+out_overflow:
+ printk(KERN_WARNING "RPC %s: server reply was truncated.\n", __FUNCTION__);
+ goto out_retry;
+}