android_kernel_xiaomi_sm8350/net/sunrpc/clnt.c
J. Bruce Fields f3680312a7 SUNRPC: Retry wrap in case of memory allocation failure.
For privacy we need to allocate extra pages to hold encrypted page data when
 wrapping requests.  This allocation may fail, and we handle that case by
 waiting and retrying.

 Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-10-18 23:19:43 -07:00

1252 lines
30 KiB
C

/*
* linux/net/sunrpc/clnt.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/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_bind_status(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;
if (xprt->ops->set_buffer_size)
xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
}
/*
* 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_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;
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 == NULL)
return;
task->tk_status = rpcauth_wrap_req(task, encode, req, p,
task->tk_msg.rpc_argp);
if (task->tk_status == -ENOMEM) {
/* XXX: Is this sane? */
rpc_delay(task, 3*HZ);
task->tk_status = -EAGAIN;
}
}
/*
* 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;
dprintk("RPC: %4d call_bind (status %d)\n",
task->tk_pid, task->tk_status);
task->tk_action = call_connect;
if (!clnt->cl_port) {
task->tk_action = call_bind_status;
task->tk_timeout = task->tk_xprt->bind_timeout;
rpc_getport(task, clnt);
}
}
/*
* 4a. Sort out bind result
*/
static void
call_bind_status(struct rpc_task *task)
{
int status = -EACCES;
if (task->tk_status >= 0) {
dprintk("RPC: %4d call_bind_status (status %d)\n",
task->tk_pid, task->tk_status);
task->tk_status = 0;
task->tk_action = call_connect;
return;
}
switch (task->tk_status) {
case -EACCES:
dprintk("RPC: %4d remote rpcbind: RPC program/version unavailable\n",
task->tk_pid);
rpc_delay(task, 3*HZ);
goto retry_bind;
case -ETIMEDOUT:
dprintk("RPC: %4d rpcbind request timed out\n",
task->tk_pid);
if (RPC_IS_SOFT(task)) {
status = -EIO;
break;
}
goto retry_bind;
case -EPFNOSUPPORT:
dprintk("RPC: %4d remote rpcbind service unavailable\n",
task->tk_pid);
break;
case -EPROTONOSUPPORT:
dprintk("RPC: %4d remote rpcbind version 2 unavailable\n",
task->tk_pid);
break;
default:
dprintk("RPC: %4d unrecognized rpcbind error (%d)\n",
task->tk_pid, -task->tk_status);
status = -EIO;
break;
}
rpc_exit(task, status);
return;
retry_bind:
task->tk_status = 0;
task->tk_action = call_bind;
return;
}
/*
* 4b. Connect to the RPC server
*/
static void
call_connect(struct rpc_task *task)
{
struct rpc_xprt *xprt = task->tk_xprt;
dprintk("RPC: %4d call_connect xprt %p %s connected\n",
task->tk_pid, xprt,
(xprt_connected(xprt) ? "is" : "is not"));
task->tk_action = call_transmit;
if (!xprt_connected(xprt)) {
task->tk_action = call_connect_status;
if (task->tk_status < 0)
return;
xprt_connect(task);
}
}
/*
* 4c. 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;
dprintk("RPC: %5u call_connect_status (status %d)\n",
task->tk_pid, task->tk_status);
task->tk_status = 0;
if (status >= 0) {
clnt->cl_stats->netreconn++;
task->tk_action = call_transmit;
return;
}
/* Something failed: remote service port may have changed */
if (clnt->cl_autobind)
clnt->cl_port = 0;
switch (status) {
case -ENOTCONN:
case -ETIMEDOUT:
case -EAGAIN:
task->tk_action = call_bind;
break;
default:
rpc_exit(task, -EIO);
break;
}
}
/*
* 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 == 0) {
call_encode(task);
/* Did the encode result in an error condition? */
if (task->tk_status != 0)
goto out_nosend;
}
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);
}
return;
out_nosend:
/* release socket write lock before attempting to handle error */
xprt_abort_transmit(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_rqst *req = task->tk_rqstp;
u32 *p = req->rq_svec[0].iov_base;
/* FIXME: check buffer size? */
p = xprt_skip_transport_header(task->tk_xprt, p);
*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;
}