kernel-ark/include/linux/net.h
Eric Dumazet 4381548237 net: sock_def_readable() and friends RCU conversion
sk_callback_lock rwlock actually protects sk->sk_sleep pointer, so we
need two atomic operations (and associated dirtying) per incoming
packet.

RCU conversion is pretty much needed :

1) Add a new structure, called "struct socket_wq" to hold all fields
that will need rcu_read_lock() protection (currently: a
wait_queue_head_t and a struct fasync_struct pointer).

[Future patch will add a list anchor for wakeup coalescing]

2) Attach one of such structure to each "struct socket" created in
sock_alloc_inode().

3) Respect RCU grace period when freeing a "struct socket_wq"

4) Change sk_sleep pointer in "struct sock" by sk_wq, pointer to "struct
socket_wq"

5) Change sk_sleep() function to use new sk->sk_wq instead of
sk->sk_sleep

6) Change sk_has_sleeper() to wq_has_sleeper() that must be used inside
a rcu_read_lock() section.

7) Change all sk_has_sleeper() callers to :
  - Use rcu_read_lock() instead of read_lock(&sk->sk_callback_lock)
  - Use wq_has_sleeper() to eventually wakeup tasks.
  - Use rcu_read_unlock() instead of read_unlock(&sk->sk_callback_lock)

8) sock_wake_async() is modified to use rcu protection as well.

9) Exceptions :
  macvtap, drivers/net/tun.c, af_unix use integrated "struct socket_wq"
instead of dynamically allocated ones. They dont need rcu freeing.

Some cleanups or followups are probably needed, (possible
sk_callback_lock conversion to a spinlock for example...).

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-01 15:00:15 -07:00

297 lines
9.6 KiB
C

/*
* NET An implementation of the SOCKET network access protocol.
* This is the master header file for the Linux NET layer,
* or, in plain English: the networking handling part of the
* kernel.
*
* Version: @(#)net.h 1.0.3 05/25/93
*
* Authors: Orest Zborowski, <obz@Kodak.COM>
* Ross Biro
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _LINUX_NET_H
#define _LINUX_NET_H
#include <linux/socket.h>
#include <asm/socket.h>
#define NPROTO AF_MAX
#define SYS_SOCKET 1 /* sys_socket(2) */
#define SYS_BIND 2 /* sys_bind(2) */
#define SYS_CONNECT 3 /* sys_connect(2) */
#define SYS_LISTEN 4 /* sys_listen(2) */
#define SYS_ACCEPT 5 /* sys_accept(2) */
#define SYS_GETSOCKNAME 6 /* sys_getsockname(2) */
#define SYS_GETPEERNAME 7 /* sys_getpeername(2) */
#define SYS_SOCKETPAIR 8 /* sys_socketpair(2) */
#define SYS_SEND 9 /* sys_send(2) */
#define SYS_RECV 10 /* sys_recv(2) */
#define SYS_SENDTO 11 /* sys_sendto(2) */
#define SYS_RECVFROM 12 /* sys_recvfrom(2) */
#define SYS_SHUTDOWN 13 /* sys_shutdown(2) */
#define SYS_SETSOCKOPT 14 /* sys_setsockopt(2) */
#define SYS_GETSOCKOPT 15 /* sys_getsockopt(2) */
#define SYS_SENDMSG 16 /* sys_sendmsg(2) */
#define SYS_RECVMSG 17 /* sys_recvmsg(2) */
#define SYS_ACCEPT4 18 /* sys_accept4(2) */
#define SYS_RECVMMSG 19 /* sys_recvmmsg(2) */
typedef enum {
SS_FREE = 0, /* not allocated */
SS_UNCONNECTED, /* unconnected to any socket */
SS_CONNECTING, /* in process of connecting */
SS_CONNECTED, /* connected to socket */
SS_DISCONNECTING /* in process of disconnecting */
} socket_state;
#define __SO_ACCEPTCON (1 << 16) /* performed a listen */
#ifdef __KERNEL__
#include <linux/stringify.h>
#include <linux/random.h>
#include <linux/wait.h>
#include <linux/fcntl.h> /* For O_CLOEXEC and O_NONBLOCK */
#include <linux/kmemcheck.h>
#include <linux/rcupdate.h>
struct poll_table_struct;
struct pipe_inode_info;
struct inode;
struct net;
#define SOCK_ASYNC_NOSPACE 0
#define SOCK_ASYNC_WAITDATA 1
#define SOCK_NOSPACE 2
#define SOCK_PASSCRED 3
#define SOCK_PASSSEC 4
#ifndef ARCH_HAS_SOCKET_TYPES
/**
* enum sock_type - Socket types
* @SOCK_STREAM: stream (connection) socket
* @SOCK_DGRAM: datagram (conn.less) socket
* @SOCK_RAW: raw socket
* @SOCK_RDM: reliably-delivered message
* @SOCK_SEQPACKET: sequential packet socket
* @SOCK_DCCP: Datagram Congestion Control Protocol socket
* @SOCK_PACKET: linux specific way of getting packets at the dev level.
* For writing rarp and other similar things on the user level.
*
* When adding some new socket type please
* grep ARCH_HAS_SOCKET_TYPE include/asm-* /socket.h, at least MIPS
* overrides this enum for binary compat reasons.
*/
enum sock_type {
SOCK_STREAM = 1,
SOCK_DGRAM = 2,
SOCK_RAW = 3,
SOCK_RDM = 4,
SOCK_SEQPACKET = 5,
SOCK_DCCP = 6,
SOCK_PACKET = 10,
};
#define SOCK_MAX (SOCK_PACKET + 1)
/* Mask which covers at least up to SOCK_MASK-1. The
* remaining bits are used as flags. */
#define SOCK_TYPE_MASK 0xf
/* Flags for socket, socketpair, accept4 */
#define SOCK_CLOEXEC O_CLOEXEC
#ifndef SOCK_NONBLOCK
#define SOCK_NONBLOCK O_NONBLOCK
#endif
#endif /* ARCH_HAS_SOCKET_TYPES */
enum sock_shutdown_cmd {
SHUT_RD = 0,
SHUT_WR = 1,
SHUT_RDWR = 2,
};
struct socket_wq {
wait_queue_head_t wait;
struct fasync_struct *fasync_list;
struct rcu_head rcu;
} ____cacheline_aligned_in_smp;
/**
* struct socket - general BSD socket
* @state: socket state (%SS_CONNECTED, etc)
* @type: socket type (%SOCK_STREAM, etc)
* @flags: socket flags (%SOCK_ASYNC_NOSPACE, etc)
* @ops: protocol specific socket operations
* @fasync_list: Asynchronous wake up list
* @file: File back pointer for gc
* @sk: internal networking protocol agnostic socket representation
* @wait: wait queue for several uses
*/
struct socket {
socket_state state;
kmemcheck_bitfield_begin(type);
short type;
kmemcheck_bitfield_end(type);
unsigned long flags;
struct socket_wq *wq;
struct file *file;
struct sock *sk;
const struct proto_ops *ops;
};
struct vm_area_struct;
struct page;
struct kiocb;
struct sockaddr;
struct msghdr;
struct module;
struct proto_ops {
int family;
struct module *owner;
int (*release) (struct socket *sock);
int (*bind) (struct socket *sock,
struct sockaddr *myaddr,
int sockaddr_len);
int (*connect) (struct socket *sock,
struct sockaddr *vaddr,
int sockaddr_len, int flags);
int (*socketpair)(struct socket *sock1,
struct socket *sock2);
int (*accept) (struct socket *sock,
struct socket *newsock, int flags);
int (*getname) (struct socket *sock,
struct sockaddr *addr,
int *sockaddr_len, int peer);
unsigned int (*poll) (struct file *file, struct socket *sock,
struct poll_table_struct *wait);
int (*ioctl) (struct socket *sock, unsigned int cmd,
unsigned long arg);
#ifdef CONFIG_COMPAT
int (*compat_ioctl) (struct socket *sock, unsigned int cmd,
unsigned long arg);
#endif
int (*listen) (struct socket *sock, int len);
int (*shutdown) (struct socket *sock, int flags);
int (*setsockopt)(struct socket *sock, int level,
int optname, char __user *optval, unsigned int optlen);
int (*getsockopt)(struct socket *sock, int level,
int optname, char __user *optval, int __user *optlen);
#ifdef CONFIG_COMPAT
int (*compat_setsockopt)(struct socket *sock, int level,
int optname, char __user *optval, unsigned int optlen);
int (*compat_getsockopt)(struct socket *sock, int level,
int optname, char __user *optval, int __user *optlen);
#endif
int (*sendmsg) (struct kiocb *iocb, struct socket *sock,
struct msghdr *m, size_t total_len);
int (*recvmsg) (struct kiocb *iocb, struct socket *sock,
struct msghdr *m, size_t total_len,
int flags);
int (*mmap) (struct file *file, struct socket *sock,
struct vm_area_struct * vma);
ssize_t (*sendpage) (struct socket *sock, struct page *page,
int offset, size_t size, int flags);
ssize_t (*splice_read)(struct socket *sock, loff_t *ppos,
struct pipe_inode_info *pipe, size_t len, unsigned int flags);
};
#define DECLARE_SOCKADDR(type, dst, src) \
type dst = ({ __sockaddr_check_size(sizeof(*dst)); (type) src; })
struct net_proto_family {
int family;
int (*create)(struct net *net, struct socket *sock,
int protocol, int kern);
struct module *owner;
};
struct iovec;
struct kvec;
enum {
SOCK_WAKE_IO,
SOCK_WAKE_WAITD,
SOCK_WAKE_SPACE,
SOCK_WAKE_URG,
};
extern int sock_wake_async(struct socket *sk, int how, int band);
extern int sock_register(const struct net_proto_family *fam);
extern void sock_unregister(int family);
extern int sock_create(int family, int type, int proto,
struct socket **res);
extern int sock_create_kern(int family, int type, int proto,
struct socket **res);
extern int sock_create_lite(int family, int type, int proto,
struct socket **res);
extern void sock_release(struct socket *sock);
extern int sock_sendmsg(struct socket *sock, struct msghdr *msg,
size_t len);
extern int sock_recvmsg(struct socket *sock, struct msghdr *msg,
size_t size, int flags);
extern int sock_map_fd(struct socket *sock, int flags);
extern struct socket *sockfd_lookup(int fd, int *err);
#define sockfd_put(sock) fput(sock->file)
extern int net_ratelimit(void);
#define net_random() random32()
#define net_srandom(seed) srandom32((__force u32)seed)
extern int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
struct kvec *vec, size_t num, size_t len);
extern int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
struct kvec *vec, size_t num,
size_t len, int flags);
extern int kernel_bind(struct socket *sock, struct sockaddr *addr,
int addrlen);
extern int kernel_listen(struct socket *sock, int backlog);
extern int kernel_accept(struct socket *sock, struct socket **newsock,
int flags);
extern int kernel_connect(struct socket *sock, struct sockaddr *addr,
int addrlen, int flags);
extern int kernel_getsockname(struct socket *sock, struct sockaddr *addr,
int *addrlen);
extern int kernel_getpeername(struct socket *sock, struct sockaddr *addr,
int *addrlen);
extern int kernel_getsockopt(struct socket *sock, int level, int optname,
char *optval, int *optlen);
extern int kernel_setsockopt(struct socket *sock, int level, int optname,
char *optval, unsigned int optlen);
extern int kernel_sendpage(struct socket *sock, struct page *page, int offset,
size_t size, int flags);
extern int kernel_sock_ioctl(struct socket *sock, int cmd, unsigned long arg);
extern int kernel_sock_shutdown(struct socket *sock,
enum sock_shutdown_cmd how);
#define MODULE_ALIAS_NETPROTO(proto) \
MODULE_ALIAS("net-pf-" __stringify(proto))
#define MODULE_ALIAS_NET_PF_PROTO(pf, proto) \
MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto))
#define MODULE_ALIAS_NET_PF_PROTO_TYPE(pf, proto, type) \
MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
"-type-" __stringify(type))
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
#include <linux/ratelimit.h>
extern struct ratelimit_state net_ratelimit_state;
#endif
#endif /* __KERNEL__ */
#endif /* _LINUX_NET_H */