linux-sg2042/net/atm/signaling.c

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/* net/atm/signaling.c - ATM signaling */
/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
#include <linux/errno.h> /* error codes */
#include <linux/kernel.h> /* printk */
#include <linux/skbuff.h>
#include <linux/wait.h>
#include <linux/sched.h> /* jiffies and HZ */
#include <linux/atm.h> /* ATM stuff */
#include <linux/atmsap.h>
#include <linux/atmsvc.h>
#include <linux/atmdev.h>
#include <linux/bitops.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include "resources.h"
#include "signaling.h"
#undef WAIT_FOR_DEMON /* #define this if system calls on SVC sockets
should block until the demon runs.
Danger: may cause nasty hangs if the demon
crashes. */
struct atm_vcc *sigd = NULL;
#ifdef WAIT_FOR_DEMON
static DECLARE_WAIT_QUEUE_HEAD(sigd_sleep);
#endif
static void sigd_put_skb(struct sk_buff *skb)
{
#ifdef WAIT_FOR_DEMON
DECLARE_WAITQUEUE(wait, current);
add_wait_queue(&sigd_sleep, &wait);
while (!sigd) {
set_current_state(TASK_UNINTERRUPTIBLE);
pr_debug("atmsvc: waiting for signaling daemon...\n");
schedule();
}
current->state = TASK_RUNNING;
remove_wait_queue(&sigd_sleep, &wait);
#else
if (!sigd) {
pr_debug("atmsvc: no signaling daemon\n");
kfree_skb(skb);
return;
}
#endif
atm_force_charge(sigd, skb->truesize);
skb_queue_tail(&sk_atm(sigd)->sk_receive_queue, skb);
sk_atm(sigd)->sk_data_ready(sk_atm(sigd), skb->len);
}
static void modify_qos(struct atm_vcc *vcc, struct atmsvc_msg *msg)
{
struct sk_buff *skb;
if (test_bit(ATM_VF_RELEASED, &vcc->flags) ||
!test_bit(ATM_VF_READY, &vcc->flags))
return;
msg->type = as_error;
if (!vcc->dev->ops->change_qos)
msg->reply = -EOPNOTSUPP;
else {
/* should lock VCC */
msg->reply = vcc->dev->ops->change_qos(vcc, &msg->qos,
msg->reply);
if (!msg->reply)
msg->type = as_okay;
}
/*
* Should probably just turn around the old skb. But the, the buffer
* space accounting needs to follow the change too. Maybe later.
*/
while (!(skb = alloc_skb(sizeof(struct atmsvc_msg), GFP_KERNEL)))
schedule();
*(struct atmsvc_msg *)skb_put(skb, sizeof(struct atmsvc_msg)) = *msg;
sigd_put_skb(skb);
}
static int sigd_send(struct atm_vcc *vcc, struct sk_buff *skb)
{
struct atmsvc_msg *msg;
struct atm_vcc *session_vcc;
struct sock *sk;
msg = (struct atmsvc_msg *) skb->data;
atomic_sub(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc);
vcc = *(struct atm_vcc **) &msg->vcc;
pr_debug("%d (0x%lx)\n", (int)msg->type, (unsigned long)vcc);
sk = sk_atm(vcc);
switch (msg->type) {
case as_okay:
sk->sk_err = -msg->reply;
clear_bit(ATM_VF_WAITING, &vcc->flags);
if (!*vcc->local.sas_addr.prv && !*vcc->local.sas_addr.pub) {
vcc->local.sas_family = AF_ATMSVC;
memcpy(vcc->local.sas_addr.prv,
msg->local.sas_addr.prv, ATM_ESA_LEN);
memcpy(vcc->local.sas_addr.pub,
msg->local.sas_addr.pub, ATM_E164_LEN + 1);
}
session_vcc = vcc->session ? vcc->session : vcc;
if (session_vcc->vpi || session_vcc->vci)
break;
session_vcc->itf = msg->pvc.sap_addr.itf;
session_vcc->vpi = msg->pvc.sap_addr.vpi;
session_vcc->vci = msg->pvc.sap_addr.vci;
if (session_vcc->vpi || session_vcc->vci)
session_vcc->qos = msg->qos;
break;
case as_error:
clear_bit(ATM_VF_REGIS, &vcc->flags);
clear_bit(ATM_VF_READY, &vcc->flags);
sk->sk_err = -msg->reply;
clear_bit(ATM_VF_WAITING, &vcc->flags);
break;
case as_indicate:
vcc = *(struct atm_vcc **)&msg->listen_vcc;
sk = sk_atm(vcc);
pr_debug("as_indicate!!!\n");
lock_sock(sk);
if (sk_acceptq_is_full(sk)) {
sigd_enq(NULL, as_reject, vcc, NULL, NULL);
dev_kfree_skb(skb);
goto as_indicate_complete;
}
sk->sk_ack_backlog++;
skb_queue_tail(&sk->sk_receive_queue, skb);
pr_debug("waking sk_sleep(sk) 0x%p\n", sk_sleep(sk));
sk->sk_state_change(sk);
as_indicate_complete:
release_sock(sk);
return 0;
case as_close:
set_bit(ATM_VF_RELEASED, &vcc->flags);
vcc_release_async(vcc, msg->reply);
goto out;
case as_modify:
modify_qos(vcc, msg);
break;
case as_addparty:
case as_dropparty:
sk->sk_err_soft = msg->reply;
/* < 0 failure, otherwise ep_ref */
clear_bit(ATM_VF_WAITING, &vcc->flags);
break;
default:
pr_alert("bad message type %d\n", (int)msg->type);
return -EINVAL;
}
sk->sk_state_change(sk);
out:
dev_kfree_skb(skb);
return 0;
}
void sigd_enq2(struct atm_vcc *vcc, enum atmsvc_msg_type type,
struct atm_vcc *listen_vcc, const struct sockaddr_atmpvc *pvc,
const struct sockaddr_atmsvc *svc, const struct atm_qos *qos,
int reply)
{
struct sk_buff *skb;
struct atmsvc_msg *msg;
static unsigned session = 0;
pr_debug("%d (0x%p)\n", (int)type, vcc);
while (!(skb = alloc_skb(sizeof(struct atmsvc_msg), GFP_KERNEL)))
schedule();
msg = (struct atmsvc_msg *)skb_put(skb, sizeof(struct atmsvc_msg));
memset(msg, 0, sizeof(*msg));
msg->type = type;
*(struct atm_vcc **) &msg->vcc = vcc;
*(struct atm_vcc **) &msg->listen_vcc = listen_vcc;
msg->reply = reply;
if (qos)
msg->qos = *qos;
if (vcc)
msg->sap = vcc->sap;
if (svc)
msg->svc = *svc;
if (vcc)
msg->local = vcc->local;
if (pvc)
msg->pvc = *pvc;
if (vcc) {
if (type == as_connect && test_bit(ATM_VF_SESSION, &vcc->flags))
msg->session = ++session;
/* every new pmp connect gets the next session number */
}
sigd_put_skb(skb);
if (vcc)
set_bit(ATM_VF_REGIS, &vcc->flags);
}
void sigd_enq(struct atm_vcc *vcc, enum atmsvc_msg_type type,
struct atm_vcc *listen_vcc, const struct sockaddr_atmpvc *pvc,
const struct sockaddr_atmsvc *svc)
{
sigd_enq2(vcc, type, listen_vcc, pvc, svc, vcc ? &vcc->qos : NULL, 0);
/* other ISP applications may use "reply" */
}
static void purge_vcc(struct atm_vcc *vcc)
{
if (sk_atm(vcc)->sk_family == PF_ATMSVC &&
!test_bit(ATM_VF_META, &vcc->flags)) {
set_bit(ATM_VF_RELEASED, &vcc->flags);
clear_bit(ATM_VF_REGIS, &vcc->flags);
vcc_release_async(vcc, -EUNATCH);
}
}
static void sigd_close(struct atm_vcc *vcc)
{
struct hlist_node *node;
struct sock *s;
int i;
pr_debug("\n");
sigd = NULL;
if (skb_peek(&sk_atm(vcc)->sk_receive_queue))
pr_err("closing with requests pending\n");
skb_queue_purge(&sk_atm(vcc)->sk_receive_queue);
read_lock(&vcc_sklist_lock);
for (i = 0; i < VCC_HTABLE_SIZE; ++i) {
struct hlist_head *head = &vcc_hash[i];
sk_for_each(s, node, head) {
vcc = atm_sk(s);
purge_vcc(vcc);
}
}
read_unlock(&vcc_sklist_lock);
}
static struct atmdev_ops sigd_dev_ops = {
.close = sigd_close,
.send = sigd_send
};
static struct atm_dev sigd_dev = {
.ops = &sigd_dev_ops,
.type = "sig",
.number = 999,
.lock = __SPIN_LOCK_UNLOCKED(sigd_dev.lock)
};
int sigd_attach(struct atm_vcc *vcc)
{
if (sigd)
return -EADDRINUSE;
pr_debug("\n");
sigd = vcc;
vcc->dev = &sigd_dev;
vcc_insert_socket(sk_atm(vcc));
set_bit(ATM_VF_META, &vcc->flags);
set_bit(ATM_VF_READY, &vcc->flags);
#ifdef WAIT_FOR_DEMON
wake_up(&sigd_sleep);
#endif
return 0;
}