diff options
Diffstat (limited to 'net/ipv4/ipvs/ip_vs_sync.c')
| -rw-r--r-- | net/ipv4/ipvs/ip_vs_sync.c | 900 |
1 files changed, 0 insertions, 900 deletions
diff --git a/net/ipv4/ipvs/ip_vs_sync.c b/net/ipv4/ipvs/ip_vs_sync.c deleted file mode 100644 index 2e5ced3d806..00000000000 --- a/net/ipv4/ipvs/ip_vs_sync.c +++ /dev/null @@ -1,900 +0,0 @@ -/* - * IPVS An implementation of the IP virtual server support for the - * LINUX operating system. IPVS is now implemented as a module - * over the NetFilter framework. IPVS can be used to build a - * high-performance and highly available server based on a - * cluster of servers. - * - * Version: $Id: ip_vs_sync.c,v 1.13 2003/06/08 09:31:19 wensong Exp $ - * - * Authors: Wensong Zhang <wensong@linuxvirtualserver.org> - * - * ip_vs_sync: sync connection info from master load balancer to backups - * through multicast - * - * Changes: - * Alexandre Cassen : Added master & backup support at a time. - * Alexandre Cassen : Added SyncID support for incoming sync - * messages filtering. - * Justin Ossevoort : Fix endian problem on sync message size. - */ - -#include <linux/module.h> -#include <linux/slab.h> -#include <linux/net.h> -#include <linux/completion.h> -#include <linux/delay.h> -#include <linux/skbuff.h> -#include <linux/in.h> -#include <linux/igmp.h> /* for ip_mc_join_group */ - -#include <net/ip.h> -#include <net/sock.h> -#include <asm/uaccess.h> /* for get_fs and set_fs */ - -#include <net/ip_vs.h> - -#define IP_VS_SYNC_GROUP 0xe0000051 /* multicast addr - 224.0.0.81 */ -#define IP_VS_SYNC_PORT 8848 /* multicast port */ - - -/* - * IPVS sync connection entry - */ -struct ip_vs_sync_conn { - __u8 reserved; - - /* Protocol, addresses and port numbers */ - __u8 protocol; /* Which protocol (TCP/UDP) */ - __u16 cport; - __u16 vport; - __u16 dport; - __u32 caddr; /* client address */ - __u32 vaddr; /* virtual address */ - __u32 daddr; /* destination address */ - - /* Flags and state transition */ - __u16 flags; /* status flags */ - __u16 state; /* state info */ - - /* The sequence options start here */ -}; - -struct ip_vs_sync_conn_options { - struct ip_vs_seq in_seq; /* incoming seq. struct */ - struct ip_vs_seq out_seq; /* outgoing seq. struct */ -}; - -#define IP_VS_SYNC_CONN_TIMEOUT (3*60*HZ) -#define SIMPLE_CONN_SIZE (sizeof(struct ip_vs_sync_conn)) -#define FULL_CONN_SIZE \ -(sizeof(struct ip_vs_sync_conn) + sizeof(struct ip_vs_sync_conn_options)) - - -/* - The master mulitcasts messages to the backup load balancers in the - following format. - - 0 1 2 3 - 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Count Conns | SyncID | Size | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | | - | IPVS Sync Connection (1) | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | . | - | . | - | . | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | | - | IPVS Sync Connection (n) | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -*/ - -#define SYNC_MESG_HEADER_LEN 4 - -struct ip_vs_sync_mesg { - __u8 nr_conns; - __u8 syncid; - __u16 size; - - /* ip_vs_sync_conn entries start here */ -}; - -/* the maximum length of sync (sending/receiving) message */ -static int sync_send_mesg_maxlen; -static int sync_recv_mesg_maxlen; - -struct ip_vs_sync_buff { - struct list_head list; - unsigned long firstuse; - - /* pointers for the message data */ - struct ip_vs_sync_mesg *mesg; - unsigned char *head; - unsigned char *end; -}; - - -/* the sync_buff list head and the lock */ -static LIST_HEAD(ip_vs_sync_queue); -static DEFINE_SPINLOCK(ip_vs_sync_lock); - -/* current sync_buff for accepting new conn entries */ -static struct ip_vs_sync_buff *curr_sb = NULL; -static DEFINE_SPINLOCK(curr_sb_lock); - -/* ipvs sync daemon state */ -volatile int ip_vs_sync_state = IP_VS_STATE_NONE; -volatile int ip_vs_master_syncid = 0; -volatile int ip_vs_backup_syncid = 0; - -/* multicast interface name */ -char ip_vs_master_mcast_ifn[IP_VS_IFNAME_MAXLEN]; -char ip_vs_backup_mcast_ifn[IP_VS_IFNAME_MAXLEN]; - -/* multicast addr */ -static struct sockaddr_in mcast_addr; - - -static inline void sb_queue_tail(struct ip_vs_sync_buff *sb) -{ - spin_lock(&ip_vs_sync_lock); - list_add_tail(&sb->list, &ip_vs_sync_queue); - spin_unlock(&ip_vs_sync_lock); -} - -static inline struct ip_vs_sync_buff * sb_dequeue(void) -{ - struct ip_vs_sync_buff *sb; - - spin_lock_bh(&ip_vs_sync_lock); - if (list_empty(&ip_vs_sync_queue)) { - sb = NULL; - } else { - sb = list_entry(ip_vs_sync_queue.next, - struct ip_vs_sync_buff, - list); - list_del(&sb->list); - } - spin_unlock_bh(&ip_vs_sync_lock); - - return sb; -} - -static inline struct ip_vs_sync_buff * ip_vs_sync_buff_create(void) -{ - struct ip_vs_sync_buff *sb; - - if (!(sb=kmalloc(sizeof(struct ip_vs_sync_buff), GFP_ATOMIC))) - return NULL; - - if (!(sb->mesg=kmalloc(sync_send_mesg_maxlen, GFP_ATOMIC))) { - kfree(sb); - return NULL; - } - sb->mesg->nr_conns = 0; - sb->mesg->syncid = ip_vs_master_syncid; - sb->mesg->size = 4; - sb->head = (unsigned char *)sb->mesg + 4; - sb->end = (unsigned char *)sb->mesg + sync_send_mesg_maxlen; - sb->firstuse = jiffies; - return sb; -} - -static inline void ip_vs_sync_buff_release(struct ip_vs_sync_buff *sb) -{ - kfree(sb->mesg); - kfree(sb); -} - -/* - * Get the current sync buffer if it has been created for more - * than the specified time or the specified time is zero. - */ -static inline struct ip_vs_sync_buff * -get_curr_sync_buff(unsigned long time) -{ - struct ip_vs_sync_buff *sb; - - spin_lock_bh(&curr_sb_lock); - if (curr_sb && (time == 0 || - time_before(jiffies - curr_sb->firstuse, time))) { - sb = curr_sb; - curr_sb = NULL; - } else - sb = NULL; - spin_unlock_bh(&curr_sb_lock); - return sb; -} - - -/* - * Add an ip_vs_conn information into the current sync_buff. - * Called by ip_vs_in. - */ -void ip_vs_sync_conn(struct ip_vs_conn *cp) -{ - struct ip_vs_sync_mesg *m; - struct ip_vs_sync_conn *s; - int len; - - spin_lock(&curr_sb_lock); - if (!curr_sb) { - if (!(curr_sb=ip_vs_sync_buff_create())) { - spin_unlock(&curr_sb_lock); - IP_VS_ERR("ip_vs_sync_buff_create failed.\n"); - return; - } - } - - len = (cp->flags & IP_VS_CONN_F_SEQ_MASK) ? FULL_CONN_SIZE : - SIMPLE_CONN_SIZE; - m = curr_sb->mesg; - s = (struct ip_vs_sync_conn *)curr_sb->head; - - /* copy members */ - s->protocol = cp->protocol; - s->cport = cp->cport; - s->vport = cp->vport; - s->dport = cp->dport; - s->caddr = cp->caddr; - s->vaddr = cp->vaddr; - s->daddr = cp->daddr; - s->flags = htons(cp->flags & ~IP_VS_CONN_F_HASHED); - s->state = htons(cp->state); - if (cp->flags & IP_VS_CONN_F_SEQ_MASK) { - struct ip_vs_sync_conn_options *opt = - (struct ip_vs_sync_conn_options *)&s[1]; - memcpy(opt, &cp->in_seq, sizeof(*opt)); - } - - m->nr_conns++; - m->size += len; - curr_sb->head += len; - - /* check if there is a space for next one */ - if (curr_sb->head+FULL_CONN_SIZE > curr_sb->end) { - sb_queue_tail(curr_sb); - curr_sb = NULL; - } - spin_unlock(&curr_sb_lock); - - /* synchronize its controller if it has */ - if (cp->control) - ip_vs_sync_conn(cp->control); -} - - -/* - * Process received multicast message and create the corresponding - * ip_vs_conn entries. - */ -static void ip_vs_process_message(const char *buffer, const size_t buflen) -{ - struct ip_vs_sync_mesg *m = (struct ip_vs_sync_mesg *)buffer; - struct ip_vs_sync_conn *s; - struct ip_vs_sync_conn_options *opt; - struct ip_vs_conn *cp; - char *p; - int i; - - /* Convert size back to host byte order */ - m->size = ntohs(m->size); - - if (buflen != m->size) { - IP_VS_ERR("bogus message\n"); - return; - } - - /* SyncID sanity check */ - if (ip_vs_backup_syncid != 0 && m->syncid != ip_vs_backup_syncid) { - IP_VS_DBG(7, "Ignoring incoming msg with syncid = %d\n", - m->syncid); - return; - } - - p = (char *)buffer + sizeof(struct ip_vs_sync_mesg); - for (i=0; i<m->nr_conns; i++) { - unsigned flags; - - s = (struct ip_vs_sync_conn *)p; - flags = ntohs(s->flags); - if (!(flags & IP_VS_CONN_F_TEMPLATE)) - cp = ip_vs_conn_in_get(s->protocol, - s->caddr, s->cport, - s->vaddr, s->vport); - else - cp = ip_vs_ct_in_get(s->protocol, - s->caddr, s->cport, - s->vaddr, s->vport); - if (!cp) { - cp = ip_vs_conn_new(s->protocol, - s->caddr, s->cport, - s->vaddr, s->vport, - s->daddr, s->dport, - flags, NULL); - if (!cp) { - IP_VS_ERR("ip_vs_conn_new failed\n"); - return; - } - cp->state = ntohs(s->state); - } else if (!cp->dest) { - /* it is an entry created by the synchronization */ - cp->state = ntohs(s->state); - cp->flags = flags | IP_VS_CONN_F_HASHED; - } /* Note that we don't touch its state and flags - if it is a normal entry. */ - - if (flags & IP_VS_CONN_F_SEQ_MASK) { - opt = (struct ip_vs_sync_conn_options *)&s[1]; - memcpy(&cp->in_seq, opt, sizeof(*opt)); - p += FULL_CONN_SIZE; - } else - p += SIMPLE_CONN_SIZE; - - atomic_set(&cp->in_pkts, sysctl_ip_vs_sync_threshold[0]); - cp->timeout = IP_VS_SYNC_CONN_TIMEOUT; - ip_vs_conn_put(cp); - - if (p > buffer+buflen) { - IP_VS_ERR("bogus message\n"); - return; - } - } -} - - -/* - * Setup loopback of outgoing multicasts on a sending socket - */ -static void set_mcast_loop(struct sock *sk, u_char loop) -{ - struct inet_sock *inet = inet_sk(sk); - - /* setsockopt(sock, SOL_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop)); */ - lock_sock(sk); - inet->mc_loop = loop ? 1 : 0; - release_sock(sk); -} - -/* - * Specify TTL for outgoing multicasts on a sending socket - */ -static void set_mcast_ttl(struct sock *sk, u_char ttl) -{ - struct inet_sock *inet = inet_sk(sk); - - /* setsockopt(sock, SOL_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)); */ - lock_sock(sk); - inet->mc_ttl = ttl; - release_sock(sk); -} - -/* - * Specifiy default interface for outgoing multicasts - */ -static int set_mcast_if(struct sock *sk, char *ifname) -{ - struct net_device *dev; - struct inet_sock *inet = inet_sk(sk); - - if ((dev = __dev_get_by_name(ifname)) == NULL) - return -ENODEV; - - if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if) - return -EINVAL; - - lock_sock(sk); - inet->mc_index = dev->ifindex; - /* inet->mc_addr = 0; */ - release_sock(sk); - - return 0; -} - - -/* - * Set the maximum length of sync message according to the - * specified interface's MTU. - */ -static int set_sync_mesg_maxlen(int sync_state) -{ - struct net_device *dev; - int num; - - if (sync_state == IP_VS_STATE_MASTER) { - if ((dev = __dev_get_by_name(ip_vs_master_mcast_ifn)) == NULL) - return -ENODEV; - - num = (dev->mtu - sizeof(struct iphdr) - - sizeof(struct udphdr) - - SYNC_MESG_HEADER_LEN - 20) / SIMPLE_CONN_SIZE; - sync_send_mesg_maxlen = - SYNC_MESG_HEADER_LEN + SIMPLE_CONN_SIZE * num; - IP_VS_DBG(7, "setting the maximum length of sync sending " - "message %d.\n", sync_send_mesg_maxlen); - } else if (sync_state == IP_VS_STATE_BACKUP) { - if ((dev = __dev_get_by_name(ip_vs_backup_mcast_ifn)) == NULL) - return -ENODEV; - - sync_recv_mesg_maxlen = dev->mtu - - sizeof(struct iphdr) - sizeof(struct udphdr); - IP_VS_DBG(7, "setting the maximum length of sync receiving " - "message %d.\n", sync_recv_mesg_maxlen); - } - - return 0; -} - - -/* - * Join a multicast group. - * the group is specified by a class D multicast address 224.0.0.0/8 - * in the in_addr structure passed in as a parameter. - */ -static int -join_mcast_group(struct sock *sk, struct in_addr *addr, char *ifname) -{ - struct ip_mreqn mreq; - struct net_device *dev; - int ret; - - memset(&mreq, 0, sizeof(mreq)); - memcpy(&mreq.imr_multiaddr, addr, sizeof(struct in_addr)); - - if ((dev = __dev_get_by_name(ifname)) == NULL) - return -ENODEV; - if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if) - return -EINVAL; - - mreq.imr_ifindex = dev->ifindex; - - lock_sock(sk); - ret = ip_mc_join_group(sk, &mreq); - release_sock(sk); - - return ret; -} - - -static int bind_mcastif_addr(struct socket *sock, char *ifname) -{ - struct net_device *dev; - u32 addr; - struct sockaddr_in sin; - - if ((dev = __dev_get_by_name(ifname)) == NULL) - return -ENODEV; - - addr = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE); - if (!addr) - IP_VS_ERR("You probably need to specify IP address on " - "multicast interface.\n"); - - IP_VS_DBG(7, "binding socket with (%s) %u.%u.%u.%u\n", - ifname, NIPQUAD(addr)); - - /* Now bind the socket with the address of multicast interface */ - sin.sin_family = AF_INET; - sin.sin_addr.s_addr = addr; - sin.sin_port = 0; - - return sock->ops->bind(sock, (struct sockaddr*)&sin, sizeof(sin)); -} - -/* - * Set up sending multicast socket over UDP - */ -static struct socket * make_send_sock(void) -{ - struct socket *sock; - - /* First create a socket */ - if (sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock) < 0) { - IP_VS_ERR("Error during creation of socket; terminating\n"); - return NULL; - } - - if (set_mcast_if(sock->sk, ip_vs_master_mcast_ifn) < 0) { - IP_VS_ERR("Error setting outbound mcast interface\n"); - goto error; - } - - set_mcast_loop(sock->sk, 0); - set_mcast_ttl(sock->sk, 1); - - if (bind_mcastif_addr(sock, ip_vs_master_mcast_ifn) < 0) { - IP_VS_ERR("Error binding address of the mcast interface\n"); - goto error; - } - - if (sock->ops->connect(sock, - (struct sockaddr*)&mcast_addr, - sizeof(struct sockaddr), 0) < 0) { - IP_VS_ERR("Error connecting to the multicast addr\n"); - goto error; - } - - return sock; - - error: - sock_release(sock); - return NULL; -} - - -/* - * Set up receiving multicast socket over UDP - */ -static struct socket * make_receive_sock(void) -{ - struct socket *sock; - - /* First create a socket */ - if (sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock) < 0) { - IP_VS_ERR("Error during creation of socket; terminating\n"); - return NULL; - } - - /* it is equivalent to the REUSEADDR option in user-space */ - sock->sk->sk_reuse = 1; - - if (sock->ops->bind(sock, - (struct sockaddr*)&mcast_addr, - sizeof(struct sockaddr)) < 0) { - IP_VS_ERR("Error binding to the multicast addr\n"); - goto error; - } - - /* join the multicast group */ - if (join_mcast_group(sock->sk, - (struct in_addr*)&mcast_addr.sin_addr, - ip_vs_backup_mcast_ifn) < 0) { - IP_VS_ERR("Error joining to the multicast group\n"); - goto error; - } - - return sock; - - error: - sock_release(sock); - return NULL; -} - - -static int -ip_vs_send_async(struct socket *sock, const char *buffer, const size_t length) -{ - struct msghdr msg = {.msg_flags = MSG_DONTWAIT|MSG_NOSIGNAL}; - struct kvec iov; - int len; - - EnterFunction(7); - iov.iov_base = (void *)buffer; - iov.iov_len = length; - - len = kernel_sendmsg(sock, &msg, &iov, 1, (size_t)(length)); - - LeaveFunction(7); - return len; -} - -static void -ip_vs_send_sync_msg(struct socket *sock, struct ip_vs_sync_mesg *msg) -{ - int msize; - - msize = msg->size; - - /* Put size in network byte order */ - msg->size = htons(msg->size); - - if (ip_vs_send_async(sock, (char *)msg, msize) != msize) - IP_VS_ERR("ip_vs_send_async error\n"); -} - -static int -ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen) -{ - struct msghdr msg = {NULL,}; - struct kvec iov; - int len; - - EnterFunction(7); - - /* Receive a packet */ - iov.iov_base = buffer; - iov.iov_len = (size_t)buflen; - - len = kernel_recvmsg(sock, &msg, &iov, 1, buflen, 0); - - if (len < 0) - return -1; - - LeaveFunction(7); - return len; -} - - -static DECLARE_WAIT_QUEUE_HEAD(sync_wait); -static pid_t sync_master_pid = 0; -static pid_t sync_backup_pid = 0; - -static DECLARE_WAIT_QUEUE_HEAD(stop_sync_wait); -static int stop_master_sync = 0; -static int stop_backup_sync = 0; - -static void sync_master_loop(void) -{ - struct socket *sock; - struct ip_vs_sync_buff *sb; - - /* create the sending multicast socket */ - sock = make_send_sock(); - if (!sock) - return; - - IP_VS_INFO("sync thread started: state = MASTER, mcast_ifn = %s, " - "syncid = %d\n", - ip_vs_master_mcast_ifn, ip_vs_master_syncid); - - for (;;) { - while ((sb=sb_dequeue())) { - ip_vs_send_sync_msg(sock, sb->mesg); - ip_vs_sync_buff_release(sb); - } - - /* check if entries stay in curr_sb for 2 seconds */ - if ((sb = get_curr_sync_buff(2*HZ))) { - ip_vs_send_sync_msg(sock, sb->mesg); - ip_vs_sync_buff_release(sb); - } - - if (stop_master_sync) - break; - - ssleep(1); - } - - /* clean up the sync_buff queue */ - while ((sb=sb_dequeue())) { - ip_vs_sync_buff_release(sb); - } - - /* clean up the current sync_buff */ - if ((sb = get_curr_sync_buff(0))) { - ip_vs_sync_buff_release(sb); - } - - /* release the sending multicast socket */ - sock_release(sock); -} - - -static void sync_backup_loop(void) -{ - struct socket *sock; - char *buf; - int len; - - if (!(buf = kmalloc(sync_recv_mesg_maxlen, GFP_ATOMIC))) { - IP_VS_ERR("sync_backup_loop: kmalloc error\n"); - return; - } - - /* create the receiving multicast socket */ - sock = make_receive_sock(); - if (!sock) - goto out; - - IP_VS_INFO("sync thread started: state = BACKUP, mcast_ifn = %s, " - "syncid = %d\n", - ip_vs_backup_mcast_ifn, ip_vs_backup_syncid); - - for (;;) { - /* do you have data now? */ - while (!skb_queue_empty(&(sock->sk->sk_receive_queue))) { - if ((len = - ip_vs_receive(sock, buf, - sync_recv_mesg_maxlen)) <= 0) { - IP_VS_ERR("receiving message error\n"); - break; - } - /* disable bottom half, because it accessed the data - shared by softirq while getting/creating conns */ - local_bh_disable(); - ip_vs_process_message(buf, len); - local_bh_enable(); - } - - if (stop_backup_sync) - break; - - ssleep(1); - } - - /* release the sending multicast socket */ - sock_release(sock); - - out: - kfree(buf); -} - - -static void set_sync_pid(int sync_state, pid_t sync_pid) -{ - if (sync_state == IP_VS_STATE_MASTER) - sync_master_pid = sync_pid; - else if (sync_state == IP_VS_STATE_BACKUP) - sync_backup_pid = sync_pid; -} - -static void set_stop_sync(int sync_state, int set) -{ - if (sync_state == IP_VS_STATE_MASTER) - stop_master_sync = set; - else if (sync_state == IP_VS_STATE_BACKUP) - stop_backup_sync = set; - else { - stop_master_sync = set; - stop_backup_sync = set; - } -} - -static int sync_thread(void *startup) -{ - DECLARE_WAITQUEUE(wait, current); - mm_segment_t oldmm; - int state; - const char *name; - - /* increase the module use count */ - ip_vs_use_count_inc(); - - if (ip_vs_sync_state & IP_VS_STATE_MASTER && !sync_master_pid) { - state = IP_VS_STATE_MASTER; - name = "ipvs_syncmaster"; - } else if (ip_vs_sync_state & IP_VS_STATE_BACKUP && !sync_backup_pid) { - state = IP_VS_STATE_BACKUP; - name = "ipvs_syncbackup"; - } else { - IP_VS_BUG(); - ip_vs_use_count_dec(); - return -EINVAL; - } - - daemonize(name); - - oldmm = get_fs(); - set_fs(KERNEL_DS); - - /* Block all signals */ - spin_lock_irq(¤t->sighand->siglock); - siginitsetinv(¤t->blocked, 0); - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - - /* set the maximum length of sync message */ - set_sync_mesg_maxlen(state); - - /* set up multicast address */ - mcast_addr.sin_family = AF_INET; - mcast_addr.sin_port = htons(IP_VS_SYNC_PORT); - mcast_addr.sin_addr.s_addr = htonl(IP_VS_SYNC_GROUP); - - add_wait_queue(&sync_wait, &wait); - - set_sync_pid(state, current->pid); - complete((struct completion *)startup); - - /* processing master/backup loop here */ - if (state == IP_VS_STATE_MASTER) - sync_master_loop(); - else if (state == IP_VS_STATE_BACKUP) - sync_backup_loop(); - else IP_VS_BUG(); - - remove_wait_queue(&sync_wait, &wait); - - /* thread exits */ - set_sync_pid(state, 0); - IP_VS_INFO("sync thread stopped!\n"); - - set_fs(oldmm); - - /* decrease the module use count */ - ip_vs_use_count_dec(); - - set_stop_sync(state, 0); - wake_up(&stop_sync_wait); - - return 0; -} - - -static int fork_sync_thread(void *startup) -{ - pid_t pid; - - /* fork the sync thread here, then the parent process of the - sync thread is the init process after this thread exits. */ - repeat: - if ((pid = kernel_thread(sync_thread, startup, 0)) < 0) { - IP_VS_ERR("could not create sync_thread due to %d... " - "retrying.\n", pid); - ssleep(1); - goto repeat; - } - - return 0; -} - - -int start_sync_thread(int state, char *mcast_ifn, __u8 syncid) -{ - DECLARE_COMPLETION(startup); - pid_t pid; - - if ((state == IP_VS_STATE_MASTER && sync_master_pid) || - (state == IP_VS_STATE_BACKUP && sync_backup_pid)) - return -EEXIST; - - IP_VS_DBG(7, "%s: pid %d\n", __FUNCTION__, current->pid); - IP_VS_DBG(7, "Each ip_vs_sync_conn entry need %Zd bytes\n", - sizeof(struct ip_vs_sync_conn)); - - ip_vs_sync_state |= state; - if (state == IP_VS_STATE_MASTER) { - strlcpy(ip_vs_master_mcast_ifn, mcast_ifn, sizeof(ip_vs_master_mcast_ifn)); - ip_vs_master_syncid = syncid; - } else { - strlcpy(ip_vs_backup_mcast_ifn, mcast_ifn, sizeof(ip_vs_backup_mcast_ifn)); - ip_vs_backup_syncid = syncid; - } - - repeat: - if ((pid = kernel_thread(fork_sync_thread, &startup, 0)) < 0) { - IP_VS_ERR("could not create fork_sync_thread due to %d... " - "retrying.\n", pid); - ssleep(1); - goto repeat; - } - - wait_for_completion(&startup); - - return 0; -} - - -int stop_sync_thread(int state) -{ - DECLARE_WAITQUEUE(wait, current); - - if ((state == IP_VS_STATE_MASTER && !sync_master_pid) || - (state == IP_VS_STATE_BACKUP && !sync_backup_pid)) - return -ESRCH; - - IP_VS_DBG(7, "%s: pid %d\n", __FUNCTION__, current->pid); - IP_VS_INFO("stopping sync thread %d ...\n", - (state == IP_VS_STATE_MASTER) ? sync_master_pid : sync_backup_pid); - - __set_current_state(TASK_UNINTERRUPTIBLE); - add_wait_queue(&stop_sync_wait, &wait); - set_stop_sync(state, 1); - ip_vs_sync_state -= state; - wake_up(&sync_wait); - schedule(); - __set_current_state(TASK_RUNNING); - remove_wait_queue(&stop_sync_wait, &wait); - - /* Note: no need to reap the sync thread, because its parent - process is the init process */ - - if ((state == IP_VS_STATE_MASTER && stop_master_sync) || - (state == IP_VS_STATE_BACKUP && stop_backup_sync)) - IP_VS_BUG(); - - return 0; -} |