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svc: Move the xprt independent code to the svc_xprt.c file

Browse Source 
This functionally trivial patch moves all of the transport independent
functions from the svcsock.c file to the transport independent svc_xprt.c
file.

In addition the following formatting changes were made:
- White space cleanup
- Function signatures on single line
- The inline directive was removed
- Lines over 80 columns were reformatted
- The term 'socket' was changed to 'transport' in comments
- The SMP comment was moved and updated.

Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Greg Banks <gnb@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This commit is contained in:
Tom Tucker 2007-12-30 21:08:27 -06:00 committed by J. Bruce Fields
parent 18d19f949d
commit 0f0257eaa5
3 changed files with 804 additions and 810 deletions
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27
include/linux/sunrpc/svc_xprt.h
View File

@ -72,9 +72,14 @@ void svc_unreg_xprt_class(struct svc_xprt_class *);
void svc_xprt_init(struct svc_xprt_class *, struct svc_xprt *,
struct svc_serv *);
int svc_create_xprt(struct svc_serv *, char *, unsigned short, int);
void svc_xprt_enqueue(struct svc_xprt *xprt);
void svc_xprt_received(struct svc_xprt *);
void svc_xprt_put(struct svc_xprt *xprt);
void svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt);
void svc_close_xprt(struct svc_xprt *xprt);
void svc_delete_xprt(struct svc_xprt *xprt);
int svc_port_is_privileged(struct sockaddr *sin);
static inline void svc_xprt_get(struct svc_xprt *xprt)
{
kref_get(&xprt->xpt_ref);
@ -126,4 +131,26 @@ static inline unsigned short svc_xprt_remote_port(struct svc_xprt *xprt)
return svc_addr_port((struct sockaddr *)&xprt->xpt_remote);
}
static inline char *__svc_print_addr(struct sockaddr *addr,
char *buf, size_t len)
{
switch (addr->sa_family) {
case AF_INET:
snprintf(buf, len, "%u.%u.%u.%u, port=%u",
NIPQUAD(((struct sockaddr_in *) addr)->sin_addr),
ntohs(((struct sockaddr_in *) addr)->sin_port));
break;
case AF_INET6:
snprintf(buf, len, "%x:%x:%x:%x:%x:%x:%x:%x, port=%u",
NIP6(((struct sockaddr_in6 *) addr)->sin6_addr),
ntohs(((struct sockaddr_in6 *) addr)->sin6_port));
break;
default:
snprintf(buf, len, "unknown address type: %d", addr->sa_family);
break;
}
return buf;
}
#endif /* SUNRPC_SVC_XPRT_H */

753
net/sunrpc/svc_xprt.c
View File

@ -35,10 +35,53 @@
#define RPCDBG_FACILITY RPCDBG_SVCXPRT
static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt);
static int svc_deferred_recv(struct svc_rqst *rqstp);
static struct cache_deferred_req *svc_defer(struct cache_req *req);
static void svc_age_temp_xprts(unsigned long closure);
/* apparently the "standard" is that clients close
* idle connections after 5 minutes, servers after
* 6 minutes
* http://www.connectathon.org/talks96/nfstcp.pdf
*/
static int svc_conn_age_period = 6*60;
/* List of registered transport classes */
static DEFINE_SPINLOCK(svc_xprt_class_lock);
static LIST_HEAD(svc_xprt_class_list);
/* SMP locking strategy:
*
* svc_pool->sp_lock protects most of the fields of that pool.
* svc_serv->sv_lock protects sv_tempsocks, sv_permsocks, sv_tmpcnt.
* when both need to be taken (rare), svc_serv->sv_lock is first.
* BKL protects svc_serv->sv_nrthread.
* svc_sock->sk_lock protects the svc_sock->sk_deferred list
* and the ->sk_info_authunix cache.
*
* The XPT_BUSY bit in xprt->xpt_flags prevents a transport being
* enqueued multiply. During normal transport processing this bit
* is set by svc_xprt_enqueue and cleared by svc_xprt_received.
* Providers should not manipulate this bit directly.
*
* Some flags can be set to certain values at any time
* providing that certain rules are followed:
*
* XPT_CONN, XPT_DATA:
* - Can be set or cleared at any time.
* - After a set, svc_xprt_enqueue must be called to enqueue
* the transport for processing.
* - After a clear, the transport must be read/accepted.
* If this succeeds, it must be set again.
* XPT_CLOSE:
* - Can set at any time. It is never cleared.
* XPT_DEAD:
* - Can only be set while XPT_BUSY is held which ensures
* that no other thread will be using the transport or will
* try to set XPT_DEAD.
*/
int svc_reg_xprt_class(struct svc_xprt_class *xcl)
{
struct svc_xprt_class *cl;
@ -178,3 +221,713 @@ void svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt)
}
EXPORT_SYMBOL_GPL(svc_xprt_copy_addrs);
/**
* svc_print_addr - Format rq_addr field for printing
* @rqstp: svc_rqst struct containing address to print
* @buf: target buffer for formatted address
* @len: length of target buffer
*
*/
char *svc_print_addr(struct svc_rqst *rqstp, char *buf, size_t len)
{
return __svc_print_addr(svc_addr(rqstp), buf, len);
}
EXPORT_SYMBOL_GPL(svc_print_addr);
/*
* Queue up an idle server thread. Must have pool->sp_lock held.
* Note: this is really a stack rather than a queue, so that we only
* use as many different threads as we need, and the rest don't pollute
* the cache.
*/
static void svc_thread_enqueue(struct svc_pool *pool, struct svc_rqst *rqstp)
{
list_add(&rqstp->rq_list, &pool->sp_threads);
}
/*
* Dequeue an nfsd thread. Must have pool->sp_lock held.
*/
static void svc_thread_dequeue(struct svc_pool *pool, struct svc_rqst *rqstp)
{
list_del(&rqstp->rq_list);
}
/*
* Queue up a transport with data pending. If there are idle nfsd
* processes, wake 'em up.
*
*/
void svc_xprt_enqueue(struct svc_xprt *xprt)
{
struct svc_serv *serv = xprt->xpt_server;
struct svc_pool *pool;
struct svc_rqst *rqstp;
int cpu;
if (!(xprt->xpt_flags &
((1<<XPT_CONN)|(1<<XPT_DATA)|(1<<XPT_CLOSE)|(1<<XPT_DEFERRED))))
return;
if (test_bit(XPT_DEAD, &xprt->xpt_flags))
return;
cpu = get_cpu();
pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
put_cpu();
spin_lock_bh(&pool->sp_lock);
if (!list_empty(&pool->sp_threads) &&
!list_empty(&pool->sp_sockets))
printk(KERN_ERR
"svc_xprt_enqueue: "
"threads and transports both waiting??\n");
if (test_bit(XPT_DEAD, &xprt->xpt_flags)) {
/* Don't enqueue dead transports */
dprintk("svc: transport %p is dead, not enqueued\n", xprt);
goto out_unlock;
}
/* Mark transport as busy. It will remain in this state until
* the provider calls svc_xprt_received. We update XPT_BUSY
* atomically because it also guards against trying to enqueue
* the transport twice.
*/
if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) {
/* Don't enqueue transport while already enqueued */
dprintk("svc: transport %p busy, not enqueued\n", xprt);
goto out_unlock;
}
BUG_ON(xprt->xpt_pool != NULL);
xprt->xpt_pool = pool;
/* Handle pending connection */
if (test_bit(XPT_CONN, &xprt->xpt_flags))
goto process;
/* Handle close in-progress */
if (test_bit(XPT_CLOSE, &xprt->xpt_flags))
goto process;
/* Check if we have space to reply to a request */
if (!xprt->xpt_ops->xpo_has_wspace(xprt)) {
/* Don't enqueue while not enough space for reply */
dprintk("svc: no write space, transport %p not enqueued\n",
xprt);
xprt->xpt_pool = NULL;
clear_bit(XPT_BUSY, &xprt->xpt_flags);
goto out_unlock;
}
process:
if (!list_empty(&pool->sp_threads)) {
rqstp = list_entry(pool->sp_threads.next,
struct svc_rqst,
rq_list);
dprintk("svc: transport %p served by daemon %p\n",
xprt, rqstp);
svc_thread_dequeue(pool, rqstp);
if (rqstp->rq_xprt)
printk(KERN_ERR
"svc_xprt_enqueue: server %p, rq_xprt=%p!\n",
rqstp, rqstp->rq_xprt);
rqstp->rq_xprt = xprt;
svc_xprt_get(xprt);
rqstp->rq_reserved = serv->sv_max_mesg;
atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved);
BUG_ON(xprt->xpt_pool != pool);
wake_up(&rqstp->rq_wait);
} else {
dprintk("svc: transport %p put into queue\n", xprt);
list_add_tail(&xprt->xpt_ready, &pool->sp_sockets);
BUG_ON(xprt->xpt_pool != pool);
}
out_unlock:
spin_unlock_bh(&pool->sp_lock);
}
EXPORT_SYMBOL_GPL(svc_xprt_enqueue);
/*
* Dequeue the first transport. Must be called with the pool->sp_lock held.
*/
static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool)
{
struct svc_xprt *xprt;
if (list_empty(&pool->sp_sockets))
return NULL;
xprt = list_entry(pool->sp_sockets.next,
struct svc_xprt, xpt_ready);
list_del_init(&xprt->xpt_ready);
dprintk("svc: transport %p dequeued, inuse=%d\n",
xprt, atomic_read(&xprt->xpt_ref.refcount));
return xprt;
}
/*
* svc_xprt_received conditionally queues the transport for processing
* by another thread. The caller must hold the XPT_BUSY bit and must
* not thereafter touch transport data.
*
* Note: XPT_DATA only gets cleared when a read-attempt finds no (or
* insufficient) data.
*/
void svc_xprt_received(struct svc_xprt *xprt)
{
BUG_ON(!test_bit(XPT_BUSY, &xprt->xpt_flags));
xprt->xpt_pool = NULL;
clear_bit(XPT_BUSY, &xprt->xpt_flags);
svc_xprt_enqueue(xprt);
}
EXPORT_SYMBOL_GPL(svc_xprt_received);
/**
* svc_reserve - change the space reserved for the reply to a request.
* @rqstp: The request in question
* @space: new max space to reserve
*
* Each request reserves some space on the output queue of the transport
* to make sure the reply fits. This function reduces that reserved
* space to be the amount of space used already, plus @space.
*
*/
void svc_reserve(struct svc_rqst *rqstp, int space)
{
space += rqstp->rq_res.head[0].iov_len;
if (space < rqstp->rq_reserved) {
struct svc_xprt *xprt = rqstp->rq_xprt;
atomic_sub((rqstp->rq_reserved - space), &xprt->xpt_reserved);
rqstp->rq_reserved = space;
svc_xprt_enqueue(xprt);
}
}
static void svc_xprt_release(struct svc_rqst *rqstp)
{
struct svc_xprt *xprt = rqstp->rq_xprt;
rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp);
svc_free_res_pages(rqstp);
rqstp->rq_res.page_len = 0;
rqstp->rq_res.page_base = 0;
/* Reset response buffer and release
* the reservation.
* But first, check that enough space was reserved
* for the reply, otherwise we have a bug!
*/
if ((rqstp->rq_res.len) > rqstp->rq_reserved)
printk(KERN_ERR "RPC request reserved %d but used %d\n",
rqstp->rq_reserved,
rqstp->rq_res.len);
rqstp->rq_res.head[0].iov_len = 0;
svc_reserve(rqstp, 0);
rqstp->rq_xprt = NULL;
svc_xprt_put(xprt);
}
/*
* External function to wake up a server waiting for data
* This really only makes sense for services like lockd
* which have exactly one thread anyway.
*/
void svc_wake_up(struct svc_serv *serv)
{
struct svc_rqst *rqstp;
unsigned int i;
struct svc_pool *pool;
for (i = 0; i < serv->sv_nrpools; i++) {
pool = &serv->sv_pools[i];
spin_lock_bh(&pool->sp_lock);
if (!list_empty(&pool->sp_threads)) {
rqstp = list_entry(pool->sp_threads.next,
struct svc_rqst,
rq_list);
dprintk("svc: daemon %p woken up.\n", rqstp);
/*
svc_thread_dequeue(pool, rqstp);
rqstp->rq_xprt = NULL;
*/
wake_up(&rqstp->rq_wait);
}
spin_unlock_bh(&pool->sp_lock);
}
}
int svc_port_is_privileged(struct sockaddr *sin)
{
switch (sin->sa_family) {
case AF_INET:
return ntohs(((struct sockaddr_in *)sin)->sin_port)
< PROT_SOCK;
case AF_INET6:
return ntohs(((struct sockaddr_in6 *)sin)->sin6_port)
< PROT_SOCK;
default:
return 0;
}
}
/*
* Make sure that we don't have too many active connections. If we
* have, something must be dropped.
*
* There's no point in trying to do random drop here for DoS
* prevention. The NFS clients does 1 reconnect in 15 seconds. An
* attacker can easily beat that.
*
* The only somewhat efficient mechanism would be if drop old
* connections from the same IP first. But right now we don't even
* record the client IP in svc_sock.
*/
static void svc_check_conn_limits(struct svc_serv *serv)
{
if (serv->sv_tmpcnt > (serv->sv_nrthreads+3)*20) {
struct svc_xprt *xprt = NULL;
spin_lock_bh(&serv->sv_lock);
if (!list_empty(&serv->sv_tempsocks)) {
if (net_ratelimit()) {
/* Try to help the admin */
printk(KERN_NOTICE "%s: too many open "
"connections, consider increasing the "
"number of nfsd threads\n",
serv->sv_name);
}
/*
* Always select the oldest connection. It's not fair,
* but so is life
*/
xprt = list_entry(serv->sv_tempsocks.prev,
struct svc_xprt,
xpt_list);
set_bit(XPT_CLOSE, &xprt->xpt_flags);
svc_xprt_get(xprt);
}
spin_unlock_bh(&serv->sv_lock);
if (xprt) {
svc_xprt_enqueue(xprt);
svc_xprt_put(xprt);
}
}
}
/*
* Receive the next request on any transport. This code is carefully
* organised not to touch any cachelines in the shared svc_serv
* structure, only cachelines in the local svc_pool.
*/
int svc_recv(struct svc_rqst *rqstp, long timeout)
{
struct svc_xprt *xprt = NULL;
struct svc_serv *serv = rqstp->rq_server;
struct svc_pool *pool = rqstp->rq_pool;
int len, i;
int pages;
struct xdr_buf *arg;
DECLARE_WAITQUEUE(wait, current);
dprintk("svc: server %p waiting for data (to = %ld)\n",
rqstp, timeout);
if (rqstp->rq_xprt)
printk(KERN_ERR
"svc_recv: service %p, transport not NULL!\n",
rqstp);
if (waitqueue_active(&rqstp->rq_wait))
printk(KERN_ERR
"svc_recv: service %p, wait queue active!\n",
rqstp);
/* now allocate needed pages. If we get a failure, sleep briefly */
pages = (serv->sv_max_mesg + PAGE_SIZE) / PAGE_SIZE;
for (i = 0; i < pages ; i++)
while (rqstp->rq_pages[i] == NULL) {
struct page *p = alloc_page(GFP_KERNEL);
if (!p) {
int j = msecs_to_jiffies(500);
schedule_timeout_uninterruptible(j);
}
rqstp->rq_pages[i] = p;
}
rqstp->rq_pages[i++] = NULL; /* this might be seen in nfs_read_actor */
BUG_ON(pages >= RPCSVC_MAXPAGES);
/* Make arg->head point to first page and arg->pages point to rest */
arg = &rqstp->rq_arg;
arg->head[0].iov_base = page_address(rqstp->rq_pages[0]);
arg->head[0].iov_len = PAGE_SIZE;
arg->pages = rqstp->rq_pages + 1;
arg->page_base = 0;
/* save at least one page for response */
arg->page_len = (pages-2)*PAGE_SIZE;
arg->len = (pages-1)*PAGE_SIZE;
arg->tail[0].iov_len = 0;
try_to_freeze();
cond_resched();
if (signalled())
return -EINTR;
spin_lock_bh(&pool->sp_lock);
xprt = svc_xprt_dequeue(pool);
if (xprt) {
rqstp->rq_xprt = xprt;
svc_xprt_get(xprt);
rqstp->rq_reserved = serv->sv_max_mesg;
atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved);
} else {
/* No data pending. Go to sleep */
svc_thread_enqueue(pool, rqstp);
/*
* We have to be able to interrupt this wait
* to bring down the daemons ...
*/
set_current_state(TASK_INTERRUPTIBLE);
add_wait_queue(&rqstp->rq_wait, &wait);
spin_unlock_bh(&pool->sp_lock);
schedule_timeout(timeout);
try_to_freeze();
spin_lock_bh(&pool->sp_lock);
remove_wait_queue(&rqstp->rq_wait, &wait);
xprt = rqstp->rq_xprt;
if (!xprt) {
svc_thread_dequeue(pool, rqstp);
spin_unlock_bh(&pool->sp_lock);
dprintk("svc: server %p, no data yet\n", rqstp);
return signalled()? -EINTR : -EAGAIN;
}
}
spin_unlock_bh(&pool->sp_lock);
len = 0;
if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) {
dprintk("svc_recv: found XPT_CLOSE\n");
svc_delete_xprt(xprt);
} else if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
struct svc_xprt *newxpt;
newxpt = xprt->xpt_ops->xpo_accept(xprt);
if (newxpt) {
/*
* We know this module_get will succeed because the
* listener holds a reference too
*/
__module_get(newxpt->xpt_class->xcl_owner);
svc_check_conn_limits(xprt->xpt_server);
spin_lock_bh(&serv->sv_lock);
set_bit(XPT_TEMP, &newxpt->xpt_flags);
list_add(&newxpt->xpt_list, &serv->sv_tempsocks);
serv->sv_tmpcnt++;
if (serv->sv_temptimer.function == NULL) {
/* setup timer to age temp transports */
setup_timer(&serv->sv_temptimer,
svc_age_temp_xprts,
(unsigned long)serv);
mod_timer(&serv->sv_temptimer,
jiffies + svc_conn_age_period * HZ);
}
spin_unlock_bh(&serv->sv_lock);
svc_xprt_received(newxpt);
}
svc_xprt_received(xprt);
} else {
dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n",
rqstp, pool->sp_id, xprt,
atomic_read(&xprt->xpt_ref.refcount));
rqstp->rq_deferred = svc_deferred_dequeue(xprt);
if (rqstp->rq_deferred) {
svc_xprt_received(xprt);
len = svc_deferred_recv(rqstp);
} else
len = xprt->xpt_ops->xpo_recvfrom(rqstp);
dprintk("svc: got len=%d\n", len);
}
/* No data, incomplete (TCP) read, or accept() */
if (len == 0 || len == -EAGAIN) {
rqstp->rq_res.len = 0;
svc_xprt_release(rqstp);
return -EAGAIN;
}
clear_bit(XPT_OLD, &xprt->xpt_flags);
rqstp->rq_secure = svc_port_is_privileged(svc_addr(rqstp));
rqstp->rq_chandle.defer = svc_defer;
if (serv->sv_stats)
serv->sv_stats->netcnt++;
return len;
}
/*
* Drop request
*/
void svc_drop(struct svc_rqst *rqstp)
{
dprintk("svc: xprt %p dropped request\n", rqstp->rq_xprt);
svc_xprt_release(rqstp);
}
/*
* Return reply to client.
*/
int svc_send(struct svc_rqst *rqstp)
{
struct svc_xprt *xprt;
int len;
struct xdr_buf *xb;
xprt = rqstp->rq_xprt;
if (!xprt)
return -EFAULT;
/* release the receive skb before sending the reply */
rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp);
/* calculate over-all length */
xb = &rqstp->rq_res;
xb->len = xb->head[0].iov_len +
xb->page_len +
xb->tail[0].iov_len;
/* Grab mutex to serialize outgoing data. */
mutex_lock(&xprt->xpt_mutex);
if (test_bit(XPT_DEAD, &xprt->xpt_flags))
len = -ENOTCONN;
else
len = xprt->xpt_ops->xpo_sendto(rqstp);
mutex_unlock(&xprt->xpt_mutex);
svc_xprt_release(rqstp);
if (len == -ECONNREFUSED || len == -ENOTCONN || len == -EAGAIN)
return 0;
return len;
}
/*
* Timer function to close old temporary transports, using
* a mark-and-sweep algorithm.
*/
static void svc_age_temp_xprts(unsigned long closure)
{
struct svc_serv *serv = (struct svc_serv *)closure;
struct svc_xprt *xprt;
struct list_head *le, *next;
LIST_HEAD(to_be_aged);
dprintk("svc_age_temp_xprts\n");
if (!spin_trylock_bh(&serv->sv_lock)) {
/* busy, try again 1 sec later */
dprintk("svc_age_temp_xprts: busy\n");
mod_timer(&serv->sv_temptimer, jiffies + HZ);
return;
}
list_for_each_safe(le, next, &serv->sv_tempsocks) {
xprt = list_entry(le, struct svc_xprt, xpt_list);
/* First time through, just mark it OLD. Second time
* through, close it. */
if (!test_and_set_bit(XPT_OLD, &xprt->xpt_flags))
continue;
if (atomic_read(&xprt->xpt_ref.refcount) > 1
|| test_bit(XPT_BUSY, &xprt->xpt_flags))
continue;
svc_xprt_get(xprt);
list_move(le, &to_be_aged);
set_bit(XPT_CLOSE, &xprt->xpt_flags);
set_bit(XPT_DETACHED, &xprt->xpt_flags);
}
spin_unlock_bh(&serv->sv_lock);
while (!list_empty(&to_be_aged)) {
le = to_be_aged.next;
/* fiddling the xpt_list node is safe 'cos we're XPT_DETACHED */
list_del_init(le);
xprt = list_entry(le, struct svc_xprt, xpt_list);
dprintk("queuing xprt %p for closing\n", xprt);
/* a thread will dequeue and close it soon */
svc_xprt_enqueue(xprt);
svc_xprt_put(xprt);
}
mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ);
}
/*
* Remove a dead transport
*/
void svc_delete_xprt(struct svc_xprt *xprt)
{
struct svc_serv *serv = xprt->xpt_server;
dprintk("svc: svc_delete_xprt(%p)\n", xprt);
xprt->xpt_ops->xpo_detach(xprt);
spin_lock_bh(&serv->sv_lock);
if (!test_and_set_bit(XPT_DETACHED, &xprt->xpt_flags))
list_del_init(&xprt->xpt_list);
/*
* We used to delete the transport from whichever list
* it's sk_xprt.xpt_ready node was on, but we don't actually
* need to. This is because the only time we're called
* while still attached to a queue, the queue itself
* is about to be destroyed (in svc_destroy).
*/
if (!test_and_set_bit(XPT_DEAD, &xprt->xpt_flags)) {
BUG_ON(atomic_read(&xprt->xpt_ref.refcount) < 2);
if (test_bit(XPT_TEMP, &xprt->xpt_flags))
serv->sv_tmpcnt--;
svc_xprt_put(xprt);
}
spin_unlock_bh(&serv->sv_lock);
}
void svc_close_xprt(struct svc_xprt *xprt)
{
set_bit(XPT_CLOSE, &xprt->xpt_flags);
if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags))
/* someone else will have to effect the close */
return;
svc_xprt_get(xprt);
svc_delete_xprt(xprt);
clear_bit(XPT_BUSY, &xprt->xpt_flags);
svc_xprt_put(xprt);
}
void svc_close_all(struct list_head *xprt_list)
{
struct svc_xprt *xprt;
struct svc_xprt *tmp;
list_for_each_entry_safe(xprt, tmp, xprt_list, xpt_list) {
set_bit(XPT_CLOSE, &xprt->xpt_flags);
if (test_bit(XPT_BUSY, &xprt->xpt_flags)) {
/* Waiting to be processed, but no threads left,
* So just remove it from the waiting list
*/
list_del_init(&xprt->xpt_ready);
clear_bit(XPT_BUSY, &xprt->xpt_flags);
}
svc_close_xprt(xprt);
}
}
/*
* Handle defer and revisit of requests
*/
static void svc_revisit(struct cache_deferred_req *dreq, int too_many)
{
struct svc_deferred_req *dr =
container_of(dreq, struct svc_deferred_req, handle);
struct svc_xprt *xprt = dr->xprt;
if (too_many) {
svc_xprt_put(xprt);
kfree(dr);
return;
}
dprintk("revisit queued\n");
dr->xprt = NULL;
spin_lock(&xprt->xpt_lock);
list_add(&dr->handle.recent, &xprt->xpt_deferred);
spin_unlock(&xprt->xpt_lock);
set_bit(XPT_DEFERRED, &xprt->xpt_flags);
svc_xprt_enqueue(xprt);
svc_xprt_put(xprt);
}
static struct cache_deferred_req *svc_defer(struct cache_req *req)
{
struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle);
int size = sizeof(struct svc_deferred_req) + (rqstp->rq_arg.len);
struct svc_deferred_req *dr;
if (rqstp->rq_arg.page_len)
return NULL; /* if more than a page, give up FIXME */
if (rqstp->rq_deferred) {
dr = rqstp->rq_deferred;
rqstp->rq_deferred = NULL;
} else {
int skip = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
/* FIXME maybe discard if size too large */
dr = kmalloc(size, GFP_KERNEL);
if (dr == NULL)
return NULL;
dr->handle.owner = rqstp->rq_server;
dr->prot = rqstp->rq_prot;
memcpy(&dr->addr, &rqstp->rq_addr, rqstp->rq_addrlen);
dr->addrlen = rqstp->rq_addrlen;
dr->daddr = rqstp->rq_daddr;
dr->argslen = rqstp->rq_arg.len >> 2;
memcpy(dr->args, rqstp->rq_arg.head[0].iov_base-skip,
dr->argslen<<2);
}
svc_xprt_get(rqstp->rq_xprt);
dr->xprt = rqstp->rq_xprt;
dr->handle.revisit = svc_revisit;
return &dr->handle;
}
/*
* recv data from a deferred request into an active one
*/
static int svc_deferred_recv(struct svc_rqst *rqstp)
{
struct svc_deferred_req *dr = rqstp->rq_deferred;
rqstp->rq_arg.head[0].iov_base = dr->args;
rqstp->rq_arg.head[0].iov_len = dr->argslen<<2;
rqstp->rq_arg.page_len = 0;
rqstp->rq_arg.len = dr->argslen<<2;
rqstp->rq_prot = dr->prot;
memcpy(&rqstp->rq_addr, &dr->addr, dr->addrlen);
rqstp->rq_addrlen = dr->addrlen;
rqstp->rq_daddr = dr->daddr;
rqstp->rq_respages = rqstp->rq_pages;
return dr->argslen<<2;
}
static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt)
{
struct svc_deferred_req *dr = NULL;
if (!test_bit(XPT_DEFERRED, &xprt->xpt_flags))
return NULL;
spin_lock(&xprt->xpt_lock);
clear_bit(XPT_DEFERRED, &xprt->xpt_flags);
if (!list_empty(&xprt->xpt_deferred)) {
dr = list_entry(xprt->xpt_deferred.next,
struct svc_deferred_req,
handle.recent);
list_del_init(&dr->handle.recent);
set_bit(XPT_DEFERRED, &xprt->xpt_flags);
}
spin_unlock(&xprt->xpt_lock);
return dr;
}

834
net/sunrpc/svcsock.c
View File

@ -48,66 +48,24 @@
#include <linux/sunrpc/svcsock.h>
#include <linux/sunrpc/stats.h>
/* SMP locking strategy:
*
* svc_pool->sp_lock protects most of the fields of that pool.
* svc_serv->sv_lock protects sv_tempsocks, sv_permsocks, sv_tmpcnt.
* when both need to be taken (rare), svc_serv->sv_lock is first.
* BKL protects svc_serv->sv_nrthread.
* svc_sock->sk_lock protects the svc_sock->sk_deferred list
* and the ->sk_info_authunix cache.
* svc_sock->sk_xprt.xpt_flags.XPT_BUSY prevents a svc_sock being
* enqueued multiply.
*
* Some flags can be set to certain values at any time
* providing that certain rules are followed:
*
* XPT_CONN, XPT_DATA, can be set or cleared at any time.
* after a set, svc_xprt_enqueue must be called.
* after a clear, the socket must be read/accepted
* if this succeeds, it must be set again.
* XPT_CLOSE can set at any time. It is never cleared.
* xpt_ref contains a bias of '1' until XPT_DEAD is set.
* so when xprt_ref hits zero, we know the transport is dead
* and no-one is using it.
* XPT_DEAD can only be set while XPT_BUSY is held which ensures
* no other thread will be using the socket or will try to
* set XPT_DEAD.
*
*/
#define RPCDBG_FACILITY RPCDBG_SVCXPRT
static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
int *errp, int flags);
static void svc_delete_xprt(struct svc_xprt *xprt);
static void svc_udp_data_ready(struct sock *, int);
static int svc_udp_recvfrom(struct svc_rqst *);
static int svc_udp_sendto(struct svc_rqst *);
static void svc_close_xprt(struct svc_xprt *xprt);
static void svc_sock_detach(struct svc_xprt *);
static void svc_sock_free(struct svc_xprt *);
static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt);
static int svc_deferred_recv(struct svc_rqst *rqstp);
static struct cache_deferred_req *svc_defer(struct cache_req *req);
static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
struct sockaddr *, int, int);
static void svc_age_temp_xprts(unsigned long closure);
/* apparently the "standard" is that clients close
* idle connections after 5 minutes, servers after
* 6 minutes
* http://www.connectathon.org/talks96/nfstcp.pdf
*/
static int svc_conn_age_period = 6*60;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
static struct lock_class_key svc_key[2];
static struct lock_class_key svc_slock_key[2];
static inline void svc_reclassify_socket(struct socket *sock)
static void svc_reclassify_socket(struct socket *sock)
{
struct sock *sk = sock->sk;
BUG_ON(sock_owned_by_user(sk));
@ -131,67 +89,11 @@ static inline void svc_reclassify_socket(struct socket *sock)
}
}
#else
static inline void svc_reclassify_socket(struct socket *sock)
static void svc_reclassify_socket(struct socket *sock)
{
}
#endif
static char *__svc_print_addr(struct sockaddr *addr, char *buf, size_t len)
{
switch (addr->sa_family) {
case AF_INET:
snprintf(buf, len, "%u.%u.%u.%u, port=%u",
NIPQUAD(((struct sockaddr_in *) addr)->sin_addr),
ntohs(((struct sockaddr_in *) addr)->sin_port));
break;
case AF_INET6:
snprintf(buf, len, "%x:%x:%x:%x:%x:%x:%x:%x, port=%u",
NIP6(((struct sockaddr_in6 *) addr)->sin6_addr),
ntohs(((struct sockaddr_in6 *) addr)->sin6_port));
break;
default:
snprintf(buf, len, "unknown address type: %d", addr->sa_family);
break;
}
return buf;
}
/**
* svc_print_addr - Format rq_addr field for printing
* @rqstp: svc_rqst struct containing address to print
* @buf: target buffer for formatted address
* @len: length of target buffer
*
*/
char *svc_print_addr(struct svc_rqst *rqstp, char *buf, size_t len)
{
return __svc_print_addr(svc_addr(rqstp), buf, len);
}
EXPORT_SYMBOL_GPL(svc_print_addr);
/*
* Queue up an idle server thread. Must have pool->sp_lock held.
* Note: this is really a stack rather than a queue, so that we only
* use as many different threads as we need, and the rest don't pollute
* the cache.
*/
static inline void
svc_thread_enqueue(struct svc_pool *pool, struct svc_rqst *rqstp)
{
list_add(&rqstp->rq_list, &pool->sp_threads);
}
/*
* Dequeue an nfsd thread. Must have pool->sp_lock held.
*/
static inline void
svc_thread_dequeue(struct svc_pool *pool, struct svc_rqst *rqstp)
{
list_del(&rqstp->rq_list);
}
/*
* Release an skbuff after use
*/
@ -214,220 +116,6 @@ static void svc_release_skb(struct svc_rqst *rqstp)
}
}
/*
* Queue up a socket with data pending. If there are idle nfsd
* processes, wake 'em up.
*
*/
void svc_xprt_enqueue(struct svc_xprt *xprt)
{
struct svc_serv *serv = xprt->xpt_server;
struct svc_pool *pool;
struct svc_rqst *rqstp;
int cpu;
if (!(xprt->xpt_flags &
((1<<XPT_CONN)|(1<<XPT_DATA)|(1<<XPT_CLOSE)|(1<<XPT_DEFERRED))))
return;
if (test_bit(XPT_DEAD, &xprt->xpt_flags))
return;
cpu = get_cpu();
pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
put_cpu();
spin_lock_bh(&pool->sp_lock);
if (!list_empty(&pool->sp_threads) &&
!list_empty(&pool->sp_sockets))
printk(KERN_ERR
"svc_xprt_enqueue: "
"threads and transports both waiting??\n");
if (test_bit(XPT_DEAD, &xprt->xpt_flags)) {
/* Don't enqueue dead sockets */
dprintk("svc: transport %p is dead, not enqueued\n", xprt);
goto out_unlock;
}
/* Mark socket as busy. It will remain in this state until the
* server has processed all pending data and put the socket back
* on the idle list. We update XPT_BUSY atomically because
* it also guards against trying to enqueue the svc_sock twice.
*/
if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) {
/* Don't enqueue socket while already enqueued */
dprintk("svc: transport %p busy, not enqueued\n", xprt);
goto out_unlock;
}
BUG_ON(xprt->xpt_pool != NULL);
xprt->xpt_pool = pool;
/* Handle pending connection */
if (test_bit(XPT_CONN, &xprt->xpt_flags))
goto process;
/* Handle close in-progress */
if (test_bit(XPT_CLOSE, &xprt->xpt_flags))
goto process;
/* Check if we have space to reply to a request */
if (!xprt->xpt_ops->xpo_has_wspace(xprt)) {
/* Don't enqueue while not enough space for reply */
dprintk("svc: no write space, transport %p not enqueued\n",
xprt);
xprt->xpt_pool = NULL;
clear_bit(XPT_BUSY, &xprt->xpt_flags);
goto out_unlock;
}
process:
if (!list_empty(&pool->sp_threads)) {
rqstp = list_entry(pool->sp_threads.next,
struct svc_rqst,
rq_list);
dprintk("svc: transport %p served by daemon %p\n",
xprt, rqstp);
svc_thread_dequeue(pool, rqstp);
if (rqstp->rq_xprt)
printk(KERN_ERR
"svc_xprt_enqueue: server %p, rq_xprt=%p!\n",
rqstp, rqstp->rq_xprt);
rqstp->rq_xprt = xprt;
svc_xprt_get(xprt);
rqstp->rq_reserved = serv->sv_max_mesg;
atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved);
BUG_ON(xprt->xpt_pool != pool);
wake_up(&rqstp->rq_wait);
} else {
dprintk("svc: transport %p put into queue\n", xprt);
list_add_tail(&xprt->xpt_ready, &pool->sp_sockets);
BUG_ON(xprt->xpt_pool != pool);
}
out_unlock:
spin_unlock_bh(&pool->sp_lock);
}
EXPORT_SYMBOL_GPL(svc_xprt_enqueue);
/*
* Dequeue the first socket. Must be called with the pool->sp_lock held.
*/
static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool)
{
struct svc_xprt *xprt;
if (list_empty(&pool->sp_sockets))
return NULL;
xprt = list_entry(pool->sp_sockets.next,
struct svc_xprt, xpt_ready);
list_del_init(&xprt->xpt_ready);
dprintk("svc: transport %p dequeued, inuse=%d\n",
xprt, atomic_read(&xprt->xpt_ref.refcount));
return xprt;
}
/*
* svc_xprt_received conditionally queues the transport for processing
* by another thread. The caller must hold the XPT_BUSY bit and must
* not thereafter touch transport data.
*
* Note: XPT_DATA only gets cleared when a read-attempt finds no (or
* insufficient) data.
*/
void svc_xprt_received(struct svc_xprt *xprt)
{
BUG_ON(!test_bit(XPT_BUSY, &xprt->xpt_flags));
xprt->xpt_pool = NULL;
clear_bit(XPT_BUSY, &xprt->xpt_flags);
svc_xprt_enqueue(xprt);
}
EXPORT_SYMBOL_GPL(svc_xprt_received);
/**
* svc_reserve - change the space reserved for the reply to a request.
* @rqstp: The request in question
* @space: new max space to reserve
*
* Each request reserves some space on the output queue of the socket
* to make sure the reply fits. This function reduces that reserved
* space to be the amount of space used already, plus @space.
*
*/
void svc_reserve(struct svc_rqst *rqstp, int space)
{
space += rqstp->rq_res.head[0].iov_len;
if (space < rqstp->rq_reserved) {
struct svc_xprt *xprt = rqstp->rq_xprt;
atomic_sub((rqstp->rq_reserved - space), &xprt->xpt_reserved);
rqstp->rq_reserved = space;
svc_xprt_enqueue(xprt);
}
}
static void svc_xprt_release(struct svc_rqst *rqstp)
{
struct svc_xprt *xprt = rqstp->rq_xprt;
rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp);
svc_free_res_pages(rqstp);
rqstp->rq_res.page_len = 0;
rqstp->rq_res.page_base = 0;
/* Reset response buffer and release
* the reservation.
* But first, check that enough space was reserved
* for the reply, otherwise we have a bug!
*/
if ((rqstp->rq_res.len) > rqstp->rq_reserved)
printk(KERN_ERR "RPC request reserved %d but used %d\n",
rqstp->rq_reserved,
rqstp->rq_res.len);
rqstp->rq_res.head[0].iov_len = 0;
svc_reserve(rqstp, 0);
rqstp->rq_xprt = NULL;
svc_xprt_put(xprt);
}
/*
* External function to wake up a server waiting for data
* This really only makes sense for services like lockd
* which have exactly one thread anyway.
*/
void
svc_wake_up(struct svc_serv *serv)
{
struct svc_rqst *rqstp;
unsigned int i;
struct svc_pool *pool;
for (i = 0; i < serv->sv_nrpools; i++) {
pool = &serv->sv_pools[i];
spin_lock_bh(&pool->sp_lock);
if (!list_empty(&pool->sp_threads)) {
rqstp = list_entry(pool->sp_threads.next,
struct svc_rqst,
rq_list);
dprintk("svc: daemon %p woken up.\n", rqstp);
/*
svc_thread_dequeue(pool, rqstp);
rqstp->rq_xprt = NULL;
*/
wake_up(&rqstp->rq_wait);
}
spin_unlock_bh(&pool->sp_lock);
}
}
union svc_pktinfo_u {
struct in_pktinfo pkti;
struct in6_pktinfo pkti6;
@ -469,8 +157,7 @@ static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
/*
* Generic sendto routine
*/
static int
svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
{
struct svc_sock *svsk =
container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
@ -605,8 +292,7 @@ EXPORT_SYMBOL(svc_sock_names);
/*
* Check input queue length
*/
static int
svc_recv_available(struct svc_sock *svsk)
static int svc_recv_available(struct svc_sock *svsk)
{
struct socket *sock = svsk->sk_sock;
int avail, err;
@ -619,8 +305,8 @@ svc_recv_available(struct svc_sock *svsk)
/*
* Generic recvfrom routine.
*/
static int
svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr, int buflen)
static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
int buflen)
{
struct svc_sock *svsk =
container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
@ -640,8 +326,8 @@ svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr, int buflen)
/*
* Set socket snd and rcv buffer lengths
*/
static inline void
svc_sock_setbufsize(struct socket *sock, unsigned int snd, unsigned int rcv)
static void svc_sock_setbufsize(struct socket *sock, unsigned int snd,
unsigned int rcv)
{
#if 0
mm_segment_t oldfs;
@ -666,8 +352,7 @@ svc_sock_setbufsize(struct socket *sock, unsigned int snd, unsigned int rcv)
/*
* INET callback when data has been received on the socket.
*/
static void
svc_udp_data_ready(struct sock *sk, int count)
static void svc_udp_data_ready(struct sock *sk, int count)
{
struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
@ -685,8 +370,7 @@ svc_udp_data_ready(struct sock *sk, int count)
/*
* INET callback when space is newly available on the socket.
*/
static void
svc_write_space(struct sock *sk)
static void svc_write_space(struct sock *sk)
{
struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data);
@ -732,8 +416,7 @@ static void svc_udp_get_dest_address(struct svc_rqst *rqstp,
/*
* Receive a datagram from a UDP socket.
*/
static int
svc_udp_recvfrom(struct svc_rqst *rqstp)
static int svc_udp_recvfrom(struct svc_rqst *rqstp)
{
struct svc_sock *svsk =
container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
@ -827,7 +510,8 @@ svc_udp_recvfrom(struct svc_rqst *rqstp)
skb_free_datagram(svsk->sk_sk, skb);
} else {
/* we can use it in-place */
rqstp->rq_arg.head[0].iov_base = skb->data + sizeof(struct udphdr);
rqstp->rq_arg.head[0].iov_base = skb->data +
sizeof(struct udphdr);
rqstp->rq_arg.head[0].iov_len = len;
if (skb_checksum_complete(skb)) {
skb_free_datagram(svsk->sk_sk, skb);
@ -938,7 +622,8 @@ static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* might have come in before data_ready set up */
/* data might have come in before data_ready set up */
set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
oldfs = get_fs();
@ -953,8 +638,7 @@ static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
* A data_ready event on a listening socket means there's a connection
* pending. Do not use state_change as a substitute for it.
*/
static void
svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
static void svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
{
struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
@ -986,8 +670,7 @@ svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
/*
* A state change on a connected socket means it's dying or dead.
*/
static void
svc_tcp_state_change(struct sock *sk)
static void svc_tcp_state_change(struct sock *sk)
{
struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
@ -1004,8 +687,7 @@ svc_tcp_state_change(struct sock *sk)
wake_up_interruptible_all(sk->sk_sleep);
}
static void
svc_tcp_data_ready(struct sock *sk, int count)
static void svc_tcp_data_ready(struct sock *sk, int count)
{
struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
@ -1019,20 +701,6 @@ svc_tcp_data_ready(struct sock *sk, int count)
wake_up_interruptible(sk->sk_sleep);
}
static inline int svc_port_is_privileged(struct sockaddr *sin)
{
switch (sin->sa_family) {
case AF_INET:
return ntohs(((struct sockaddr_in *)sin)->sin_port)
< PROT_SOCK;
case AF_INET6:
return ntohs(((struct sockaddr_in6 *)sin)->sin6_port)
< PROT_SOCK;
default:
return 0;
}
}
/*
* Accept a TCP connection
*/
@ -1115,8 +783,7 @@ failed:
/*
* Receive data from a TCP socket.
*/
static int
svc_tcp_recvfrom(struct svc_rqst *rqstp)
static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
{
struct svc_sock *svsk =
container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
@ -1269,8 +936,7 @@ svc_tcp_recvfrom(struct svc_rqst *rqstp)
/*
* Send out data on TCP socket.
*/
static int
svc_tcp_sendto(struct svc_rqst *rqstp)
static int svc_tcp_sendto(struct svc_rqst *rqstp)
{
struct xdr_buf *xbufp = &rqstp->rq_res;
int sent;
@ -1288,7 +954,9 @@ svc_tcp_sendto(struct svc_rqst *rqstp)
sent = svc_sendto(rqstp, &rqstp->rq_res);
if (sent != xbufp->len) {
printk(KERN_NOTICE "rpc-srv/tcp: %s: %s %d when sending %d bytes - shutting down socket\n",
printk(KERN_NOTICE
"rpc-srv/tcp: %s: %s %d when sending %d bytes "
"- shutting down socket\n",
rqstp->rq_xprt->xpt_server->sv_name,
(sent<0)?"got error":"sent only",
sent, xbufp->len);
@ -1410,8 +1078,7 @@ static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
}
}
void
svc_sock_update_bufs(struct svc_serv *serv)
void svc_sock_update_bufs(struct svc_serv *serv)
{
/*
* The number of server threads has changed. Update
@ -1433,302 +1100,6 @@ svc_sock_update_bufs(struct svc_serv *serv)
spin_unlock_bh(&serv->sv_lock);
}
/*
* Make sure that we don't have too many active connections. If we
* have, something must be dropped.
*
* There's no point in trying to do random drop here for DoS
* prevention. The NFS clients does 1 reconnect in 15 seconds. An
* attacker can easily beat that.
*
* The only somewhat efficient mechanism would be if drop old
* connections from the same IP first. But right now we don't even
* record the client IP in svc_sock.
*/
static void svc_check_conn_limits(struct svc_serv *serv)
{
if (serv->sv_tmpcnt > (serv->sv_nrthreads+3)*20) {
struct svc_xprt *xprt = NULL;
spin_lock_bh(&serv->sv_lock);
if (!list_empty(&serv->sv_tempsocks)) {
if (net_ratelimit()) {
/* Try to help the admin */
printk(KERN_NOTICE "%s: too many open "
"connections, consider increasing the "
"number of nfsd threads\n",
serv->sv_name);
}
/*
* Always select the oldest connection. It's not fair,
* but so is life
*/
xprt = list_entry(serv->sv_tempsocks.prev,
struct svc_xprt,
xpt_list);
set_bit(XPT_CLOSE, &xprt->xpt_flags);
svc_xprt_get(xprt);
}
spin_unlock_bh(&serv->sv_lock);
if (xprt) {
svc_xprt_enqueue(xprt);
svc_xprt_put(xprt);
}
}
}
/*
* Receive the next request on any socket. This code is carefully
* organised not to touch any cachelines in the shared svc_serv
* structure, only cachelines in the local svc_pool.
*/
int
svc_recv(struct svc_rqst *rqstp, long timeout)
{
struct svc_xprt *xprt = NULL;
struct svc_serv *serv = rqstp->rq_server;
struct svc_pool *pool = rqstp->rq_pool;
int len, i;
int pages;
struct xdr_buf *arg;
DECLARE_WAITQUEUE(wait, current);
dprintk("svc: server %p waiting for data (to = %ld)\n",
rqstp, timeout);
if (rqstp->rq_xprt)
printk(KERN_ERR
"svc_recv: service %p, transport not NULL!\n",
rqstp);
if (waitqueue_active(&rqstp->rq_wait))
printk(KERN_ERR
"svc_recv: service %p, wait queue active!\n",
rqstp);
/* now allocate needed pages. If we get a failure, sleep briefly */
pages = (serv->sv_max_mesg + PAGE_SIZE) / PAGE_SIZE;
for (i=0; i < pages ; i++)
while (rqstp->rq_pages[i] == NULL) {
struct page *p = alloc_page(GFP_KERNEL);
if (!p)
schedule_timeout_uninterruptible(msecs_to_jiffies(500));
rqstp->rq_pages[i] = p;
}
rqstp->rq_pages[i++] = NULL; /* this might be seen in nfs_read_actor */
BUG_ON(pages >= RPCSVC_MAXPAGES);
/* Make arg->head point to first page and arg->pages point to rest */
arg = &rqstp->rq_arg;
arg->head[0].iov_base = page_address(rqstp->rq_pages[0]);
arg->head[0].iov_len = PAGE_SIZE;
arg->pages = rqstp->rq_pages + 1;
arg->page_base = 0;
/* save at least one page for response */
arg->page_len = (pages-2)*PAGE_SIZE;
arg->len = (pages-1)*PAGE_SIZE;
arg->tail[0].iov_len = 0;
try_to_freeze();
cond_resched();
if (signalled())
return -EINTR;
spin_lock_bh(&pool->sp_lock);
xprt = svc_xprt_dequeue(pool);
if (xprt) {
rqstp->rq_xprt = xprt;
svc_xprt_get(xprt);
rqstp->rq_reserved = serv->sv_max_mesg;
atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved);
} else {
/* No data pending. Go to sleep */
svc_thread_enqueue(pool, rqstp);
/*
* We have to be able to interrupt this wait
* to bring down the daemons ...
*/
set_current_state(TASK_INTERRUPTIBLE);
add_wait_queue(&rqstp->rq_wait, &wait);
spin_unlock_bh(&pool->sp_lock);
schedule_timeout(timeout);
try_to_freeze();
spin_lock_bh(&pool->sp_lock);
remove_wait_queue(&rqstp->rq_wait, &wait);
xprt = rqstp->rq_xprt;
if (!xprt) {
svc_thread_dequeue(pool, rqstp);
spin_unlock_bh(&pool->sp_lock);
dprintk("svc: server %p, no data yet\n", rqstp);
return signalled()? -EINTR : -EAGAIN;
}
}
spin_unlock_bh(&pool->sp_lock);
len = 0;
if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) {
dprintk("svc_recv: found XPT_CLOSE\n");
svc_delete_xprt(xprt);
} else if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
struct svc_xprt *newxpt;
newxpt = xprt->xpt_ops->xpo_accept(xprt);
if (newxpt) {
/*
* We know this module_get will succeed because the
* listener holds a reference too
*/
__module_get(newxpt->xpt_class->xcl_owner);
svc_check_conn_limits(xprt->xpt_server);
spin_lock_bh(&serv->sv_lock);
set_bit(XPT_TEMP, &newxpt->xpt_flags);
list_add(&newxpt->xpt_list, &serv->sv_tempsocks);
serv->sv_tmpcnt++;
if (serv->sv_temptimer.function == NULL) {
/* setup timer to age temp sockets */
setup_timer(&serv->sv_temptimer,
svc_age_temp_xprts,
(unsigned long)serv);
mod_timer(&serv->sv_temptimer,
jiffies + svc_conn_age_period * HZ);
}
spin_unlock_bh(&serv->sv_lock);
svc_xprt_received(newxpt);
}
svc_xprt_received(xprt);
} else {
dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n",
rqstp, pool->sp_id, xprt,
atomic_read(&xprt->xpt_ref.refcount));
rqstp->rq_deferred = svc_deferred_dequeue(xprt);
if (rqstp->rq_deferred) {
svc_xprt_received(xprt);
len = svc_deferred_recv(rqstp);
} else
len = xprt->xpt_ops->xpo_recvfrom(rqstp);
dprintk("svc: got len=%d\n", len);
}
/* No data, incomplete (TCP) read, or accept() */
if (len == 0 || len == -EAGAIN) {
rqstp->rq_res.len = 0;
svc_xprt_release(rqstp);
return -EAGAIN;
}
clear_bit(XPT_OLD, &xprt->xpt_flags);
rqstp->rq_secure = svc_port_is_privileged(svc_addr(rqstp));
rqstp->rq_chandle.defer = svc_defer;
if (serv->sv_stats)
serv->sv_stats->netcnt++;
return len;
}
/*
* Drop request
*/
void
svc_drop(struct svc_rqst *rqstp)
{
dprintk("svc: xprt %p dropped request\n", rqstp->rq_xprt);
svc_xprt_release(rqstp);
}
/*
* Return reply to client.
*/
int
svc_send(struct svc_rqst *rqstp)
{
struct svc_xprt *xprt;
int len;
struct xdr_buf *xb;
xprt = rqstp->rq_xprt;
if (!xprt)
return -EFAULT;
/* release the receive skb before sending the reply */
rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp);
/* calculate over-all length */
xb = & rqstp->rq_res;
xb->len = xb->head[0].iov_len +
xb->page_len +
xb->tail[0].iov_len;
/* Grab mutex to serialize outgoing data. */
mutex_lock(&xprt->xpt_mutex);
if (test_bit(XPT_DEAD, &xprt->xpt_flags))
len = -ENOTCONN;
else
len = xprt->xpt_ops->xpo_sendto(rqstp);
mutex_unlock(&xprt->xpt_mutex);
svc_xprt_release(rqstp);
if (len == -ECONNREFUSED || len == -ENOTCONN || len == -EAGAIN)
return 0;
return len;
}
/*
* Timer function to close old temporary sockets, using
* a mark-and-sweep algorithm.
*/
static void svc_age_temp_xprts(unsigned long closure)
{
struct svc_serv *serv = (struct svc_serv *)closure;
struct svc_xprt *xprt;
struct list_head *le, *next;
LIST_HEAD(to_be_aged);
dprintk("svc_age_temp_xprts\n");
if (!spin_trylock_bh(&serv->sv_lock)) {
/* busy, try again 1 sec later */
dprintk("svc_age_temp_xprts: busy\n");
mod_timer(&serv->sv_temptimer, jiffies + HZ);
return;
}
list_for_each_safe(le, next, &serv->sv_tempsocks) {
xprt = list_entry(le, struct svc_xprt, xpt_list);
/* First time through, just mark it OLD. Second time
* through, close it. */
if (!test_and_set_bit(XPT_OLD, &xprt->xpt_flags))
continue;
if (atomic_read(&xprt->xpt_ref.refcount) > 1
|| test_bit(XPT_BUSY, &xprt->xpt_flags))
continue;
svc_xprt_get(xprt);
list_move(le, &to_be_aged);
set_bit(XPT_CLOSE, &xprt->xpt_flags);
set_bit(XPT_DETACHED, &xprt->xpt_flags);
}
spin_unlock_bh(&serv->sv_lock);
while (!list_empty(&to_be_aged)) {
le = to_be_aged.next;
/* fiddling the xpt_list node is safe 'cos we're XPT_DETACHED */
list_del_init(le);
xprt = list_entry(le, struct svc_xprt, xpt_list);
dprintk("queuing xprt %p for closing\n", xprt);
/* a thread will dequeue and close it soon */
svc_xprt_enqueue(xprt);
svc_xprt_put(xprt);
}
mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ);
}
/*
* Initialize socket for RPC use and create svc_sock struct
* XXX: May want to setsockopt SO_SNDBUF and SO_RCVBUF.
@ -1913,160 +1284,3 @@ static void svc_sock_free(struct svc_xprt *xprt)
sock_release(svsk->sk_sock);
kfree(svsk);
}
/*
* Remove a dead transport
*/
static void svc_delete_xprt(struct svc_xprt *xprt)
{
struct svc_serv *serv = xprt->xpt_server;
dprintk("svc: svc_delete_xprt(%p)\n", xprt);
xprt->xpt_ops->xpo_detach(xprt);
spin_lock_bh(&serv->sv_lock);
if (!test_and_set_bit(XPT_DETACHED, &xprt->xpt_flags))
list_del_init(&xprt->xpt_list);
/*
* We used to delete the transport from whichever list
* it's sk_xprt.xpt_ready node was on, but we don't actually
* need to. This is because the only time we're called
* while still attached to a queue, the queue itself
* is about to be destroyed (in svc_destroy).
*/
if (!test_and_set_bit(XPT_DEAD, &xprt->xpt_flags)) {
BUG_ON(atomic_read(&xprt->xpt_ref.refcount) < 2);
if (test_bit(XPT_TEMP, &xprt->xpt_flags))
serv->sv_tmpcnt--;
svc_xprt_put(xprt);
}
spin_unlock_bh(&serv->sv_lock);
}
static void svc_close_xprt(struct svc_xprt *xprt)
{
set_bit(XPT_CLOSE, &xprt->xpt_flags);
if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags))
/* someone else will have to effect the close */
return;
svc_xprt_get(xprt);
svc_delete_xprt(xprt);
clear_bit(XPT_BUSY, &xprt->xpt_flags);
svc_xprt_put(xprt);
}
void svc_close_all(struct list_head *xprt_list)
{
struct svc_xprt *xprt;
struct svc_xprt *tmp;
list_for_each_entry_safe(xprt, tmp, xprt_list, xpt_list) {
set_bit(XPT_CLOSE, &xprt->xpt_flags);
if (test_bit(XPT_BUSY, &xprt->xpt_flags)) {
/* Waiting to be processed, but no threads left,
* So just remove it from the waiting list
*/
list_del_init(&xprt->xpt_ready);
clear_bit(XPT_BUSY, &xprt->xpt_flags);
}
svc_close_xprt(xprt);
}
}
/*
* Handle defer and revisit of requests
*/
static void svc_revisit(struct cache_deferred_req *dreq, int too_many)
{
struct svc_deferred_req *dr = container_of(dreq, struct svc_deferred_req, handle);
struct svc_xprt *xprt = dr->xprt;
if (too_many) {
svc_xprt_put(xprt);
kfree(dr);
return;
}
dprintk("revisit queued\n");
dr->xprt = NULL;
spin_lock(&xprt->xpt_lock);
list_add(&dr->handle.recent, &xprt->xpt_deferred);
spin_unlock(&xprt->xpt_lock);
set_bit(XPT_DEFERRED, &xprt->xpt_flags);
svc_xprt_enqueue(xprt);
svc_xprt_put(xprt);
}
static struct cache_deferred_req *
svc_defer(struct cache_req *req)
{
struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle);
int size = sizeof(struct svc_deferred_req) + (rqstp->rq_arg.len);
struct svc_deferred_req *dr;
if (rqstp->rq_arg.page_len)
return NULL; /* if more than a page, give up FIXME */
if (rqstp->rq_deferred) {
dr = rqstp->rq_deferred;
rqstp->rq_deferred = NULL;
} else {
int skip = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
/* FIXME maybe discard if size too large */
dr = kmalloc(size, GFP_KERNEL);
if (dr == NULL)
return NULL;
dr->handle.owner = rqstp->rq_server;
dr->prot = rqstp->rq_prot;
memcpy(&dr->addr, &rqstp->rq_addr, rqstp->rq_addrlen);
dr->addrlen = rqstp->rq_addrlen;
dr->daddr = rqstp->rq_daddr;
dr->argslen = rqstp->rq_arg.len >> 2;
memcpy(dr->args, rqstp->rq_arg.head[0].iov_base-skip, dr->argslen<<2);
}
svc_xprt_get(rqstp->rq_xprt);
dr->xprt = rqstp->rq_xprt;
dr->handle.revisit = svc_revisit;
return &dr->handle;
}
/*
* recv data from a deferred request into an active one
*/
static int svc_deferred_recv(struct svc_rqst *rqstp)
{
struct svc_deferred_req *dr = rqstp->rq_deferred;
rqstp->rq_arg.head[0].iov_base = dr->args;
rqstp->rq_arg.head[0].iov_len = dr->argslen<<2;
rqstp->rq_arg.page_len = 0;
rqstp->rq_arg.len = dr->argslen<<2;
rqstp->rq_prot = dr->prot;
memcpy(&rqstp->rq_addr, &dr->addr, dr->addrlen);
rqstp->rq_addrlen = dr->addrlen;
rqstp->rq_daddr = dr->daddr;
rqstp->rq_respages = rqstp->rq_pages;
return dr->argslen<<2;
}
static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt)
{
struct svc_deferred_req *dr = NULL;
if (!test_bit(XPT_DEFERRED, &xprt->xpt_flags))
return NULL;
spin_lock(&xprt->xpt_lock);
clear_bit(XPT_DEFERRED, &xprt->xpt_flags);
if (!list_empty(&xprt->xpt_deferred)) {
dr = list_entry(xprt->xpt_deferred.next,
struct svc_deferred_req,
handle.recent);
list_del_init(&dr->handle.recent);
set_bit(XPT_DEFERRED, &xprt->xpt_flags);
}
spin_unlock(&xprt->xpt_lock);
return dr;
}