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OpenCloudOS-Kernel/net/sunrpc/clnt.c

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/*
* 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_new_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;
struct rpc_auth *auth;
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;
auth = rpcauth_create(flavor, clnt);
if (IS_ERR(auth)) {
printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
flavor);
err = PTR_ERR(auth);
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:
xprt_destroy(xprt);
return ERR_PTR(err);
}
/**
* Create an RPC client
* @xprt - pointer to xprt struct
* @servname - name of server
* @info - rpc_program
* @version - rpc_program version
* @authflavor - rpc_auth flavour to use
*
* Creates an RPC client structure, then pings the server in order to
* determine if it is up, and if it supports this program and version.
*
* This function should never be called by asynchronous tasks such as
* the portmapper.
*/
struct rpc_clnt *rpc_create_client(struct rpc_xprt *xprt, char *servname,
struct rpc_program *info, u32 version, rpc_authflavor_t authflavor)
{
struct rpc_clnt *clnt;
int err;
clnt = rpc_new_client(xprt, servname, info, version, authflavor);
if (IS_ERR(clnt))
return clnt;
err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
if (err == 0)
return clnt;
rpc_shutdown_client(clnt);
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);
new->cl_pmap = &new->cl_pmap_default;
rpc_init_wait_queue(&new->cl_pmap_default.pm_bindwait, "bindwait");
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);
}
/**
* rpc_bind_new_program - bind a new RPC program to an existing client
* @old - old rpc_client
* @program - rpc program to set
* @vers - rpc program version
*
* Clones the rpc client and sets up a new RPC program. This is mainly
* of use for enabling different RPC programs to share the same transport.
* The Sun NFSv2/v3 ACL protocol can do this.
*/
struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
struct rpc_program *program,
int vers)
{
struct rpc_clnt *clnt;
struct rpc_version *version;
int err;
BUG_ON(vers >= program->nrvers || !program->version[vers]);
version = program->version[vers];
clnt = rpc_clone_client(old);
if (IS_ERR(clnt))
goto out;
clnt->cl_procinfo = version->procs;
clnt->cl_maxproc = version->nrprocs;
clnt->cl_protname = program->name;
clnt->cl_prog = program->number;
clnt->cl_vers = version->number;
clnt->cl_stats = program->stats;
err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
if (err != 0) {
rpc_shutdown_client(clnt);
clnt = ERR_PTR(err);
}
out:
return clnt;
}
/*
* Default callback for async RPC calls
*/
static void
rpc_default_callback(struct rpc_task *task)
{
}
/*
* Export the signal mask handling for synchronous code that
* sleeps on RPC calls
*/
#define RPC_INTR_SIGNALS (sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGKILL))
static void rpc_save_sigmask(sigset_t *oldset, int intr)
{
unsigned long sigallow = 0;
sigset_t sigmask;
/* Block all signals except those listed in sigallow */
if (intr)
sigallow |= RPC_INTR_SIGNALS;
siginitsetinv(&sigmask, sigallow);
sigprocmask(SIG_BLOCK, &sigmask, oldset);
}
static inline void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset)
{
rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task));
}
static inline void rpc_restore_sigmask(sigset_t *oldset)
{
sigprocmask(SIG_SETMASK, oldset, NULL);
}
void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset)
{
rpc_save_sigmask(oldset, clnt->cl_intr);
}
void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset)
{
rpc_restore_sigmask(oldset);
}
/*
* 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);
status = -ENOMEM;
task = rpc_new_task(clnt, NULL, flags);
if (task == NULL)
goto out;
/* Mask signals on RPC calls _and_ GSS_AUTH upcalls */
rpc_task_sigmask(task, &oldset);
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);
}
rpc_restore_sigmask(&oldset);
out:
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;
/* 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;
/* Mask signals on GSS_AUTH upcalls */
rpc_task_sigmask(task, &oldset);
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);
rpc_restore_sigmask(&oldset);
out:
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) || !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 */
p = rpcauth_marshcred(task, p);
req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
return 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:
dprintk("%s: RPC call version mismatch!\n", __FUNCTION__);
error = -EPROTONOSUPPORT;
goto out_err;
default:
dprintk("%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:
dprintk("RPC: call_verify: program %u is unsupported by server %s\n",
(unsigned int)task->tk_client->cl_prog,
task->tk_client->cl_server);
error = -EPFNOSUPPORT;
goto out_err;
case RPC_PROG_MISMATCH:
dprintk("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);
error = -EPROTONOSUPPORT;
goto out_err;
case RPC_PROC_UNAVAIL:
dprintk("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);
error = -EOPNOTSUPP;
goto out_err;
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("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;
}
static int rpcproc_encode_null(void *rqstp, u32 *data, void *obj)
{
return 0;
}
static int rpcproc_decode_null(void *rqstp, u32 *data, void *obj)
{
return 0;
}
static struct rpc_procinfo rpcproc_null = {
.p_encode = rpcproc_encode_null,
.p_decode = rpcproc_decode_null,
};
int rpc_ping(struct rpc_clnt *clnt, int flags)
{
struct rpc_message msg = {
.rpc_proc = &rpcproc_null,
};
int err;
msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
err = rpc_call_sync(clnt, &msg, flags);
put_rpccred(msg.rpc_cred);
return err;
}
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