#include <linux/filter.h>
#include <linux/rculist_nulls.h>
+#include <linux/poll.h>
#include <asm/atomic.h>
#include <net/dst.h>
/**
* struct sock_common - minimal network layer representation of sockets
+ * @skc_node: main hash linkage for various protocol lookup tables
+ * @skc_nulls_node: main hash linkage for UDP/UDP-Lite protocol
+ * @skc_refcnt: reference count
+ * @skc_hash: hash value used with various protocol lookup tables
* @skc_family: network address family
* @skc_state: Connection state
* @skc_reuse: %SO_REUSEADDR setting
* @skc_bound_dev_if: bound device index if != 0
- * @skc_node: main hash linkage for various protocol lookup tables
- * @skc_nulls_node: main hash linkage for UDP/UDP-Lite protocol
* @skc_bind_node: bind hash linkage for various protocol lookup tables
- * @skc_refcnt: reference count
- * @skc_hash: hash value used with various protocol lookup tables
* @skc_prot: protocol handlers inside a network family
* @skc_net: reference to the network namespace of this socket
*
* for struct sock and struct inet_timewait_sock.
*/
struct sock_common {
- unsigned short skc_family;
- volatile unsigned char skc_state;
- unsigned char skc_reuse;
- int skc_bound_dev_if;
+ /*
+ * first fields are not copied in sock_copy()
+ */
union {
struct hlist_node skc_node;
struct hlist_nulls_node skc_nulls_node;
};
- struct hlist_node skc_bind_node;
atomic_t skc_refcnt;
+
unsigned int skc_hash;
+ unsigned short skc_family;
+ volatile unsigned char skc_state;
+ unsigned char skc_reuse;
+ int skc_bound_dev_if;
+ struct hlist_node skc_bind_node;
struct proto *skc_prot;
#ifdef CONFIG_NET_NS
struct net *skc_net;
* don't add nothing before this first member (__sk_common) --acme
*/
struct sock_common __sk_common;
+#define sk_node __sk_common.skc_node
+#define sk_nulls_node __sk_common.skc_nulls_node
+#define sk_refcnt __sk_common.skc_refcnt
+
+#define sk_copy_start __sk_common.skc_hash
+#define sk_hash __sk_common.skc_hash
#define sk_family __sk_common.skc_family
#define sk_state __sk_common.skc_state
#define sk_reuse __sk_common.skc_reuse
#define sk_bound_dev_if __sk_common.skc_bound_dev_if
-#define sk_node __sk_common.skc_node
-#define sk_nulls_node __sk_common.skc_nulls_node
#define sk_bind_node __sk_common.skc_bind_node
-#define sk_refcnt __sk_common.skc_refcnt
-#define sk_hash __sk_common.skc_hash
#define sk_prot __sk_common.skc_prot
#define sk_net __sk_common.skc_net
+ kmemcheck_bitfield_begin(flags);
unsigned char sk_shutdown : 2,
sk_no_check : 2,
sk_userlocks : 4;
+ kmemcheck_bitfield_end(flags);
unsigned char sk_protocol;
unsigned short sk_type;
int sk_rcvbuf;
void (*shutdown)(struct sock *sk, int how);
int (*setsockopt)(struct sock *sk, int level,
int optname, char __user *optval,
- int optlen);
+ unsigned int optlen);
int (*getsockopt)(struct sock *sk, int level,
int optname, char __user *optval,
int __user *option);
int (*compat_setsockopt)(struct sock *sk,
int level,
int optname, char __user *optval,
- int optlen);
+ unsigned int optlen);
int (*compat_getsockopt)(struct sock *sk,
int level,
int optname, char __user *optval,
extern int sock_setsockopt(struct socket *sock, int level,
int op, char __user *optval,
- int optlen);
+ unsigned int optlen);
extern int sock_getsockopt(struct socket *sock, int level,
int op, char __user *optval,
extern int sock_no_getsockopt(struct socket *, int , int,
char __user *, int __user *);
extern int sock_no_setsockopt(struct socket *, int, int,
- char __user *, int);
+ char __user *, unsigned int);
extern int sock_no_sendmsg(struct kiocb *, struct socket *,
struct msghdr *, size_t);
extern int sock_no_recvmsg(struct kiocb *, struct socket *,
extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, size_t size, int flags);
extern int sock_common_setsockopt(struct socket *sock, int level, int optname,
- char __user *optval, int optlen);
+ char __user *optval, unsigned int optlen);
extern int compat_sock_common_getsockopt(struct socket *sock, int level,
int optname, char __user *optval, int __user *optlen);
extern int compat_sock_common_setsockopt(struct socket *sock, int level,
- int optname, char __user *optval, int optlen);
+ int optname, char __user *optval, unsigned int optlen);
extern void sk_common_release(struct sock *sk);
return 0;
}
+/**
+ * sk_wmem_alloc_get - returns write allocations
+ * @sk: socket
+ *
+ * Returns sk_wmem_alloc minus initial offset of one
+ */
+static inline int sk_wmem_alloc_get(const struct sock *sk)
+{
+ return atomic_read(&sk->sk_wmem_alloc) - 1;
+}
+
+/**
+ * sk_rmem_alloc_get - returns read allocations
+ * @sk: socket
+ *
+ * Returns sk_rmem_alloc
+ */
+static inline int sk_rmem_alloc_get(const struct sock *sk)
+{
+ return atomic_read(&sk->sk_rmem_alloc);
+}
+
+/**
+ * sk_has_allocations - check if allocations are outstanding
+ * @sk: socket
+ *
+ * Returns true if socket has write or read allocations
+ */
+static inline int sk_has_allocations(const struct sock *sk)
+{
+ return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
+}
+
+/**
+ * sk_has_sleeper - check if there are any waiting processes
+ * @sk: socket
+ *
+ * Returns true if socket has waiting processes
+ *
+ * The purpose of the sk_has_sleeper and sock_poll_wait is to wrap the memory
+ * barrier call. They were added due to the race found within the tcp code.
+ *
+ * Consider following tcp code paths:
+ *
+ * CPU1 CPU2
+ *
+ * sys_select receive packet
+ * ... ...
+ * __add_wait_queue update tp->rcv_nxt
+ * ... ...
+ * tp->rcv_nxt check sock_def_readable
+ * ... {
+ * schedule ...
+ * if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
+ * wake_up_interruptible(sk->sk_sleep)
+ * ...
+ * }
+ *
+ * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
+ * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
+ * could then endup calling schedule and sleep forever if there are no more
+ * data on the socket.
+ *
+ * The sk_has_sleeper is always called right after a call to read_lock, so we
+ * can use smp_mb__after_lock barrier.
+ */
+static inline int sk_has_sleeper(struct sock *sk)
+{
+ /*
+ * We need to be sure we are in sync with the
+ * add_wait_queue modifications to the wait queue.
+ *
+ * This memory barrier is paired in the sock_poll_wait.
+ */
+ smp_mb__after_lock();
+ return sk->sk_sleep && waitqueue_active(sk->sk_sleep);
+}
+
+/**
+ * sock_poll_wait - place memory barrier behind the poll_wait call.
+ * @filp: file
+ * @wait_address: socket wait queue
+ * @p: poll_table
+ *
+ * See the comments in the sk_has_sleeper function.
+ */
+static inline void sock_poll_wait(struct file *filp,
+ wait_queue_head_t *wait_address, poll_table *p)
+{
+ if (p && wait_address) {
+ poll_wait(filp, wait_address, p);
+ /*
+ * We need to be sure we are in sync with the
+ * socket flags modification.
+ *
+ * This memory barrier is paired in the sk_has_sleeper.
+ */
+ smp_mb();
+ }
+}
+
/*
* Queue a received datagram if it will fit. Stream and sequenced
* protocols can't normally use this as they need to fit buffers in
static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
{
- sock_hold(sk);
+ skb_orphan(skb);
skb->sk = sk;
skb->destructor = sock_wfree;
+ /*
+ * We used to take a refcount on sk, but following operation
+ * is enough to guarantee sk_free() wont free this sock until
+ * all in-flight packets are completed
+ */
atomic_add(skb->truesize, &sk->sk_wmem_alloc);
}
static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
{
+ skb_orphan(skb);
skb->sk = sk;
skb->destructor = sock_rfree;
atomic_add(skb->truesize, &sk->sk_rmem_alloc);
git.openpandora.org / pandora-kernel.git / blobdiff