diff options
Diffstat (limited to 'kernel/power/tuxonice_cluster.c')
| -rw-r--r-- | kernel/power/tuxonice_cluster.c | 1058 |
1 files changed, 1058 insertions, 0 deletions
diff --git a/kernel/power/tuxonice_cluster.c b/kernel/power/tuxonice_cluster.c new file mode 100644 index 000000000..2873f93c6 --- /dev/null +++ b/kernel/power/tuxonice_cluster.c @@ -0,0 +1,1058 @@ +/* + * kernel/power/tuxonice_cluster.c + * + * Copyright (C) 2006-2015 Nigel Cunningham (nigel at nigelcunningham com au) + * + * This file is released under the GPLv2. + * + * This file contains routines for cluster hibernation support. + * + * Based on ip autoconfiguration code in net/ipv4/ipconfig.c. + * + * How does it work? + * + * There is no 'master' node that tells everyone else what to do. All nodes + * send messages to the broadcast address/port, maintain a list of peers + * and figure out when to progress to the next step in hibernating or resuming. + * This makes us more fault tolerant when it comes to nodes coming and going + * (which may be more of an issue if we're hibernating when power supplies + * are being unreliable). + * + * At boot time, we start a ktuxonice thread that handles communication with + * other nodes. This node maintains a state machine that controls our progress + * through hibernating and resuming, keeping us in step with other nodes. Nodes + * are identified by their hw address. + * + * On startup, the node sends CLUSTER_PING on the configured interface's + * broadcast address, port $toi_cluster_port (see below) and begins to listen + * for other broadcast messages. CLUSTER_PING messages are repeated at + * intervals of 5 minutes, with a random offset to spread traffic out. + * + * A hibernation cycle is initiated from any node via + * + * echo > /sys/power/tuxonice/do_hibernate + * + * and (possibily) the hibernate script. At each step of the process, the node + * completes its work, and waits for all other nodes to signal completion of + * their work (or timeout) before progressing to the next step. + * + * Request/state Action before reply Possible reply Next state + * HIBERNATE capable, pre-script HIBERNATE|ACK NODE_PREP + * HIBERNATE|NACK INIT_0 + * + * PREP prepare_image PREP|ACK IMAGE_WRITE + * PREP|NACK INIT_0 + * ABORT RUNNING + * + * IO write image IO|ACK power off + * ABORT POST_RESUME + * + * (Boot time) check for image IMAGE|ACK RESUME_PREP + * (Note 1) + * IMAGE|NACK (Note 2) + * + * PREP prepare read image PREP|ACK IMAGE_READ + * PREP|NACK (As NACK_IMAGE) + * + * IO read image IO|ACK POST_RESUME + * + * POST_RESUME thaw, post-script RUNNING + * + * INIT_0 init 0 + * + * Other messages: + * + * - PING: Request for all other live nodes to send a PONG. Used at startup to + * announce presence, when a node is suspected dead and periodically, in case + * segments of the network are [un]plugged. + * + * - PONG: Response to a PING. + * + * - ABORT: Request to cancel writing an image. + * + * - BYE: Notification that this node is shutting down. + * + * Note 1: Repeated at 3s intervals until we continue to boot/resume, so that + * nodes which are slower to start up can get state synchronised. If a node + * starting up sees other nodes sending RESUME_PREP or IMAGE_READ, it may send + * ACK_IMAGE and they will wait for it to catch up. If it sees ACK_READ, it + * must invalidate its image (if any) and boot normally. + * + * Note 2: May occur when one node lost power or powered off while others + * hibernated. This node waits for others to complete resuming (ACK_READ) + * before completing its boot, so that it appears as a fail node restarting. + * + * If any node has an image, then it also has a list of nodes that hibernated + * in synchronisation with it. The node will wait for other nodes to appear + * or timeout before beginning its restoration. + * + * If a node has no image, it needs to wait, in case other nodes which do have + * an image are going to resume, but are taking longer to announce their + * presence. For this reason, the user can specify a timeout value and a number + * of nodes detected before we just continue. (We might want to assume in a + * cluster of, say, 15 nodes, if 8 others have booted without finding an image, + * the remaining nodes will too. This might help in situations where some nodes + * are much slower to boot, or more subject to hardware failures or such like). + */ + +#include <linux/suspend.h> +#include <linux/if.h> +#include <linux/rtnetlink.h> +#include <linux/ip.h> +#include <linux/udp.h> +#include <linux/in.h> +#include <linux/if_arp.h> +#include <linux/kthread.h> +#include <linux/wait.h> +#include <linux/netdevice.h> +#include <net/ip.h> + +#include "tuxonice.h" +#include "tuxonice_modules.h" +#include "tuxonice_sysfs.h" +#include "tuxonice_alloc.h" +#include "tuxonice_io.h" + +#if 1 +#define PRINTK(a, b...) do { printk(a, ##b); } while (0) +#else +#define PRINTK(a, b...) do { } while (0) +#endif + +static int loopback_mode; +static int num_local_nodes = 1; +#define MAX_LOCAL_NODES 8 +#define SADDR (loopback_mode ? b->sid : h->saddr) + +#define MYNAME "TuxOnIce Clustering" + +enum cluster_message { + MSG_ACK = 1, + MSG_NACK = 2, + MSG_PING = 4, + MSG_ABORT = 8, + MSG_BYE = 16, + MSG_HIBERNATE = 32, + MSG_IMAGE = 64, + MSG_IO = 128, + MSG_RUNNING = 256 +}; + +static char *str_message(int message) +{ + switch (message) { + case 4: + return "Ping"; + case 8: + return "Abort"; + case 9: + return "Abort acked"; + case 10: + return "Abort nacked"; + case 16: + return "Bye"; + case 17: + return "Bye acked"; + case 18: + return "Bye nacked"; + case 32: + return "Hibernate request"; + case 33: + return "Hibernate ack"; + case 34: + return "Hibernate nack"; + case 64: + return "Image exists?"; + case 65: + return "Image does exist"; + case 66: + return "No image here"; + case 128: + return "I/O"; + case 129: + return "I/O okay"; + case 130: + return "I/O failed"; + case 256: + return "Running"; + default: + printk(KERN_ERR "Unrecognised message %d.\n", message); + return "Unrecognised message (see dmesg)"; + } +} + +#define MSG_ACK_MASK (MSG_ACK | MSG_NACK) +#define MSG_STATE_MASK (~MSG_ACK_MASK) + +struct node_info { + struct list_head member_list; + wait_queue_head_t member_events; + spinlock_t member_list_lock; + spinlock_t receive_lock; + int peer_count, ignored_peer_count; + struct toi_sysfs_data sysfs_data; + enum cluster_message current_message; +}; + +struct node_info node_array[MAX_LOCAL_NODES]; + +struct cluster_member { + __be32 addr; + enum cluster_message message; + struct list_head list; + int ignore; +}; + +#define toi_cluster_port_send 3501 +#define toi_cluster_port_recv 3502 + +static struct net_device *net_dev; +static struct toi_module_ops toi_cluster_ops; + +static int toi_recv(struct sk_buff *skb, struct net_device *dev, + struct packet_type *pt, struct net_device *orig_dev); + +static struct packet_type toi_cluster_packet_type = { + .type = __constant_htons(ETH_P_IP), + .func = toi_recv, +}; + +struct toi_pkt { /* BOOTP packet format */ + struct iphdr iph; /* IP header */ + struct udphdr udph; /* UDP header */ + u8 htype; /* HW address type */ + u8 hlen; /* HW address length */ + __be32 xid; /* Transaction ID */ + __be16 secs; /* Seconds since we started */ + __be16 flags; /* Just what it says */ + u8 hw_addr[16]; /* Sender's HW address */ + u16 message; /* Message */ + unsigned long sid; /* Source ID for loopback testing */ +}; + +static char toi_cluster_iface[IFNAMSIZ] = CONFIG_TOI_DEFAULT_CLUSTER_INTERFACE; + +static int added_pack; + +static int others_have_image; + +/* Key used to allow multiple clusters on the same lan */ +static char toi_cluster_key[32] = CONFIG_TOI_DEFAULT_CLUSTER_KEY; +static char pre_hibernate_script[255] = + CONFIG_TOI_DEFAULT_CLUSTER_PRE_HIBERNATE; +static char post_hibernate_script[255] = + CONFIG_TOI_DEFAULT_CLUSTER_POST_HIBERNATE; + +/* List of cluster members */ +static unsigned long continue_delay = 5 * HZ; +static unsigned long cluster_message_timeout = 3 * HZ; + +/* === Membership list === */ + +static void print_member_info(int index) +{ + struct cluster_member *this; + + printk(KERN_INFO "==> Dumping node %d.\n", index); + + list_for_each_entry(this, &node_array[index].member_list, list) + printk(KERN_INFO "%d.%d.%d.%d last message %s. %s\n", + NIPQUAD(this->addr), + str_message(this->message), + this->ignore ? "(Ignored)" : ""); + printk(KERN_INFO "== Done ==\n"); +} + +static struct cluster_member *__find_member(int index, __be32 addr) +{ + struct cluster_member *this; + + list_for_each_entry(this, &node_array[index].member_list, list) { + if (this->addr != addr) + continue; + + return this; + } + + return NULL; +} + +static void set_ignore(int index, __be32 addr, struct cluster_member *this) +{ + if (this->ignore) { + PRINTK("Node %d already ignoring %d.%d.%d.%d.\n", + index, NIPQUAD(addr)); + return; + } + + PRINTK("Node %d sees node %d.%d.%d.%d now being ignored.\n", + index, NIPQUAD(addr)); + this->ignore = 1; + node_array[index].ignored_peer_count++; +} + +static int __add_update_member(int index, __be32 addr, int message) +{ + struct cluster_member *this; + + this = __find_member(index, addr); + if (this) { + if (this->message != message) { + this->message = message; + if ((message & MSG_NACK) && + (message & (MSG_HIBERNATE | MSG_IMAGE | MSG_IO))) + set_ignore(index, addr, this); + PRINTK("Node %d sees node %d.%d.%d.%d now sending " + "%s.\n", index, NIPQUAD(addr), + str_message(message)); + wake_up(&node_array[index].member_events); + } + return 0; + } + + this = (struct cluster_member *) toi_kzalloc(36, + sizeof(struct cluster_member), GFP_KERNEL); + + if (!this) + return -1; + + this->addr = addr; + this->message = message; + this->ignore = 0; + INIT_LIST_HEAD(&this->list); + + node_array[index].peer_count++; + + PRINTK("Node %d sees node %d.%d.%d.%d sending %s.\n", index, + NIPQUAD(addr), str_message(message)); + + if ((message & MSG_NACK) && + (message & (MSG_HIBERNATE | MSG_IMAGE | MSG_IO))) + set_ignore(index, addr, this); + list_add_tail(&this->list, &node_array[index].member_list); + return 1; +} + +static int add_update_member(int index, __be32 addr, int message) +{ + int result; + unsigned long flags; + spin_lock_irqsave(&node_array[index].member_list_lock, flags); + result = __add_update_member(index, addr, message); + spin_unlock_irqrestore(&node_array[index].member_list_lock, flags); + + print_member_info(index); + + wake_up(&node_array[index].member_events); + + return result; +} + +static void del_member(int index, __be32 addr) +{ + struct cluster_member *this; + unsigned long flags; + + spin_lock_irqsave(&node_array[index].member_list_lock, flags); + this = __find_member(index, addr); + + if (this) { + list_del_init(&this->list); + toi_kfree(36, this, sizeof(*this)); + node_array[index].peer_count--; + } + + spin_unlock_irqrestore(&node_array[index].member_list_lock, flags); +} + +/* === Message transmission === */ + +static void toi_send_if(int message, unsigned long my_id); + +/* + * Process received TOI packet. + */ +static int toi_recv(struct sk_buff *skb, struct net_device *dev, + struct packet_type *pt, struct net_device *orig_dev) +{ + struct toi_pkt *b; + struct iphdr *h; + int len, result, index; + unsigned long addr, message, ack; + + /* Perform verifications before taking the lock. */ + if (skb->pkt_type == PACKET_OTHERHOST) + goto drop; + + if (dev != net_dev) + goto drop; + + skb = skb_share_check(skb, GFP_ATOMIC); + if (!skb) + return NET_RX_DROP; + + if (!pskb_may_pull(skb, + sizeof(struct iphdr) + + sizeof(struct udphdr))) + goto drop; + + b = (struct toi_pkt *)skb_network_header(skb); + h = &b->iph; + + if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP) + goto drop; + + /* Fragments are not supported */ + if (h->frag_off & htons(IP_OFFSET | IP_MF)) { + if (net_ratelimit()) + printk(KERN_ERR "TuxOnIce: Ignoring fragmented " + "cluster message.\n"); + goto drop; + } + + if (skb->len < ntohs(h->tot_len)) + goto drop; + + if (ip_fast_csum((char *) h, h->ihl)) + goto drop; + + if (b->udph.source != htons(toi_cluster_port_send) || + b->udph.dest != htons(toi_cluster_port_recv)) + goto drop; + + if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr)) + goto drop; + + len = ntohs(b->udph.len) - sizeof(struct udphdr); + + /* Ok the front looks good, make sure we can get at the rest. */ + if (!pskb_may_pull(skb, skb->len)) + goto drop; + + b = (struct toi_pkt *)skb_network_header(skb); + h = &b->iph; + + addr = SADDR; + PRINTK(">>> Message %s received from " NIPQUAD_FMT ".\n", + str_message(b->message), NIPQUAD(addr)); + + message = b->message & MSG_STATE_MASK; + ack = b->message & MSG_ACK_MASK; + + for (index = 0; index < num_local_nodes; index++) { + int new_message = node_array[index].current_message, + old_message = new_message; + + if (index == SADDR || !old_message) { + PRINTK("Ignoring node %d (offline or self).\n", index); + continue; + } + + /* One message at a time, please. */ + spin_lock(&node_array[index].receive_lock); + + result = add_update_member(index, SADDR, b->message); + if (result == -1) { + printk(KERN_INFO "Failed to add new cluster member " + NIPQUAD_FMT ".\n", + NIPQUAD(addr)); + goto drop_unlock; + } + + switch (b->message & MSG_STATE_MASK) { + case MSG_PING: + break; + case MSG_ABORT: + break; + case MSG_BYE: + break; + case MSG_HIBERNATE: + /* Can I hibernate? */ + new_message = MSG_HIBERNATE | + ((index & 1) ? MSG_NACK : MSG_ACK); + break; + case MSG_IMAGE: + /* Can I resume? */ + new_message = MSG_IMAGE | + ((index & 1) ? MSG_NACK : MSG_ACK); + if (new_message != old_message) + printk(KERN_ERR "Setting whether I can resume " + "to %d.\n", new_message); + break; + case MSG_IO: + new_message = MSG_IO | MSG_ACK; + break; + case MSG_RUNNING: + break; + default: + if (net_ratelimit()) + printk(KERN_ERR "Unrecognised TuxOnIce cluster" + " message %d from " NIPQUAD_FMT ".\n", + b->message, NIPQUAD(addr)); + }; + + if (old_message != new_message) { + node_array[index].current_message = new_message; + printk(KERN_INFO ">>> Sending new message for node " + "%d.\n", index); + toi_send_if(new_message, index); + } else if (!ack) { + printk(KERN_INFO ">>> Resending message for node %d.\n", + index); + toi_send_if(new_message, index); + } +drop_unlock: + spin_unlock(&node_array[index].receive_lock); + }; + +drop: + /* Throw the packet out. */ + kfree_skb(skb); + + return 0; +} + +/* + * Send cluster message to single interface. + */ +static void toi_send_if(int message, unsigned long my_id) +{ + struct sk_buff *skb; + struct toi_pkt *b; + int hh_len = LL_RESERVED_SPACE(net_dev); + struct iphdr *h; + + /* Allocate packet */ + skb = alloc_skb(sizeof(struct toi_pkt) + hh_len + 15, GFP_KERNEL); + if (!skb) + return; + skb_reserve(skb, hh_len); + b = (struct toi_pkt *) skb_put(skb, sizeof(struct toi_pkt)); + memset(b, 0, sizeof(struct toi_pkt)); + + /* Construct IP header */ + skb_reset_network_header(skb); + h = ip_hdr(skb); + h->version = 4; + h->ihl = 5; + h->tot_len = htons(sizeof(struct toi_pkt)); + h->frag_off = htons(IP_DF); + h->ttl = 64; + h->protocol = IPPROTO_UDP; + h->daddr = htonl(INADDR_BROADCAST); + h->check = ip_fast_csum((unsigned char *) h, h->ihl); + + /* Construct UDP header */ + b->udph.source = htons(toi_cluster_port_send); + b->udph.dest = htons(toi_cluster_port_recv); + b->udph.len = htons(sizeof(struct toi_pkt) - sizeof(struct iphdr)); + /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */ + + /* Construct message */ + b->message = message; + b->sid = my_id; + b->htype = net_dev->type; /* can cause undefined behavior */ + b->hlen = net_dev->addr_len; + memcpy(b->hw_addr, net_dev->dev_addr, net_dev->addr_len); + b->secs = htons(3); /* 3 seconds */ + + /* Chain packet down the line... */ + skb->dev = net_dev; + skb->protocol = htons(ETH_P_IP); + if ((dev_hard_header(skb, net_dev, ntohs(skb->protocol), + net_dev->broadcast, net_dev->dev_addr, skb->len) < 0) || + dev_queue_xmit(skb) < 0) + printk(KERN_INFO "E"); +} + +/* ========================================= */ + +/* kTOICluster */ + +static atomic_t num_cluster_threads; +static DECLARE_WAIT_QUEUE_HEAD(clusterd_events); + +static int kTOICluster(void *data) +{ + unsigned long my_id; + + my_id = atomic_add_return(1, &num_cluster_threads) - 1; + node_array[my_id].current_message = (unsigned long) data; + + PRINTK("kTOICluster daemon %lu starting.\n", my_id); + + current->flags |= PF_NOFREEZE; + + while (node_array[my_id].current_message) { + toi_send_if(node_array[my_id].current_message, my_id); + sleep_on_timeout(&clusterd_events, + cluster_message_timeout); + PRINTK("Link state %lu is %d.\n", my_id, + node_array[my_id].current_message); + } + + toi_send_if(MSG_BYE, my_id); + atomic_dec(&num_cluster_threads); + wake_up(&clusterd_events); + + PRINTK("kTOICluster daemon %lu exiting.\n", my_id); + __set_current_state(TASK_RUNNING); + return 0; +} + +static void kill_clusterd(void) +{ + int i; + + for (i = 0; i < num_local_nodes; i++) { + if (node_array[i].current_message) { + PRINTK("Seeking to kill clusterd %d.\n", i); + node_array[i].current_message = 0; + } + } + wait_event(clusterd_events, + !atomic_read(&num_cluster_threads)); + PRINTK("All cluster daemons have exited.\n"); +} + +static int peers_not_in_message(int index, int message, int precise) +{ + struct cluster_member *this; + unsigned long flags; + int result = 0; + + spin_lock_irqsave(&node_array[index].member_list_lock, flags); + list_for_each_entry(this, &node_array[index].member_list, list) { + if (this->ignore) + continue; + + PRINTK("Peer %d.%d.%d.%d sending %s. " + "Seeking %s.\n", + NIPQUAD(this->addr), + str_message(this->message), str_message(message)); + if ((precise ? this->message : + this->message & MSG_STATE_MASK) != + message) + result++; + } + spin_unlock_irqrestore(&node_array[index].member_list_lock, flags); + PRINTK("%d peers in sought message.\n", result); + return result; +} + +static void reset_ignored(int index) +{ + struct cluster_member *this; + unsigned long flags; + + spin_lock_irqsave(&node_array[index].member_list_lock, flags); + list_for_each_entry(this, &node_array[index].member_list, list) + this->ignore = 0; + node_array[index].ignored_peer_count = 0; + spin_unlock_irqrestore(&node_array[index].member_list_lock, flags); +} + +static int peers_in_message(int index, int message, int precise) +{ + return node_array[index].peer_count - + node_array[index].ignored_peer_count - + peers_not_in_message(index, message, precise); +} + +static int time_to_continue(int index, unsigned long start, int message) +{ + int first = peers_not_in_message(index, message, 0); + int second = peers_in_message(index, message, 1); + + PRINTK("First part returns %d, second returns %d.\n", first, second); + + if (!first && !second) { + PRINTK("All peers answered message %d.\n", + message); + return 1; + } + + if (time_after(jiffies, start + continue_delay)) { + PRINTK("Timeout reached.\n"); + return 1; + } + + PRINTK("Not time to continue yet (%lu < %lu).\n", jiffies, + start + continue_delay); + return 0; +} + +void toi_initiate_cluster_hibernate(void) +{ + int result; + unsigned long start; + + result = do_toi_step(STEP_HIBERNATE_PREPARE_IMAGE); + if (result) + return; + + toi_send_if(MSG_HIBERNATE, 0); + + start = jiffies; + wait_event(node_array[0].member_events, + time_to_continue(0, start, MSG_HIBERNATE)); + + if (test_action_state(TOI_FREEZER_TEST)) { + toi_send_if(MSG_ABORT, 0); + + start = jiffies; + wait_event(node_array[0].member_events, + time_to_continue(0, start, MSG_RUNNING)); + + do_toi_step(STEP_QUIET_CLEANUP); + return; + } + + toi_send_if(MSG_IO, 0); + + result = do_toi_step(STEP_HIBERNATE_SAVE_IMAGE); + if (result) + return; + + /* This code runs at resume time too! */ + if (toi_in_hibernate) + result = do_toi_step(STEP_HIBERNATE_POWERDOWN); +} + +/* toi_cluster_print_debug_stats + * + * Description: Print information to be recorded for debugging purposes into a + * buffer. + * Arguments: buffer: Pointer to a buffer into which the debug info will be + * printed. + * size: Size of the buffer. + * Returns: Number of characters written to the buffer. + */ +static int toi_cluster_print_debug_stats(char *buffer, int size) +{ + int len; + + if (strlen(toi_cluster_iface)) + len = scnprintf(buffer, size, + "- Cluster interface is '%s'.\n", + toi_cluster_iface); + else + len = scnprintf(buffer, size, + "- Cluster support is disabled.\n"); + return len; +} + +/* cluster_memory_needed + * + * Description: Tell the caller how much memory we need to operate during + * hibernate/resume. + * Returns: Unsigned long. Maximum number of bytes of memory required for + * operation. + */ +static int toi_cluster_memory_needed(void) +{ + return 0; +} + +static int toi_cluster_storage_needed(void) +{ + return 1 + strlen(toi_cluster_iface); +} + +/* toi_cluster_save_config_info + * + * Description: Save informaton needed when reloading the image at resume time. + * Arguments: Buffer: Pointer to a buffer of size PAGE_SIZE. + * Returns: Number of bytes used for saving our data. + */ +static int toi_cluster_save_config_info(char *buffer) +{ + strcpy(buffer, toi_cluster_iface); + return strlen(toi_cluster_iface + 1); +} + +/* toi_cluster_load_config_info + * + * Description: Reload information needed for declustering the image at + * resume time. + * Arguments: Buffer: Pointer to the start of the data. + * Size: Number of bytes that were saved. + */ +static void toi_cluster_load_config_info(char *buffer, int size) +{ + strncpy(toi_cluster_iface, buffer, size); + return; +} + +static void cluster_startup(void) +{ + int have_image = do_check_can_resume(), i; + unsigned long start = jiffies, initial_message; + struct task_struct *p; + + initial_message = MSG_IMAGE; + + have_image = 1; + + for (i = 0; i < num_local_nodes; i++) { + PRINTK("Starting ktoiclusterd %d.\n", i); + p = kthread_create(kTOICluster, (void *) initial_message, + "ktoiclusterd/%d", i); + if (IS_ERR(p)) { + printk(KERN_ERR "Failed to start ktoiclusterd.\n"); + return; + } + + wake_up_process(p); + } + + /* Wait for delay or someone else sending first message */ + wait_event(node_array[0].member_events, time_to_continue(0, start, + MSG_IMAGE)); + + others_have_image = peers_in_message(0, MSG_IMAGE | MSG_ACK, 1); + + printk(KERN_INFO "Continuing. I %shave an image. Peers with image:" + " %d.\n", have_image ? "" : "don't ", others_have_image); + + if (have_image) { + int result; + + /* Start to resume */ + printk(KERN_INFO " === Starting to resume === \n"); + node_array[0].current_message = MSG_IO; + toi_send_if(MSG_IO, 0); + + /* result = do_toi_step(STEP_RESUME_LOAD_PS1); */ + result = 0; + + if (!result) { + /* + * Atomic restore - we'll come back in the hibernation + * path. + */ + + /* result = do_toi_step(STEP_RESUME_DO_RESTORE); */ + result = 0; + + /* do_toi_step(STEP_QUIET_CLEANUP); */ + } + + node_array[0].current_message |= MSG_NACK; + + /* For debugging - disable for real life? */ + wait_event(node_array[0].member_events, + time_to_continue(0, start, MSG_IO)); + } + + if (others_have_image) { + /* Wait for them to resume */ + printk(KERN_INFO "Waiting for other nodes to resume.\n"); + start = jiffies; + wait_event(node_array[0].member_events, + time_to_continue(0, start, MSG_RUNNING)); + if (peers_not_in_message(0, MSG_RUNNING, 0)) + printk(KERN_INFO "Timed out while waiting for other " + "nodes to resume.\n"); + } + + /* Find out whether an image exists here. Send ACK_IMAGE or NACK_IMAGE + * as appropriate. + * + * If we don't have an image: + * - Wait until someone else says they have one, or conditions are met + * for continuing to boot (n machines or t seconds). + * - If anyone has an image, wait for them to resume before continuing + * to boot. + * + * If we have an image: + * - Wait until conditions are met before continuing to resume (n + * machines or t seconds). Send RESUME_PREP and freeze processes. + * NACK_PREP if freezing fails (shouldn't) and follow logic for + * us having no image above. On success, wait for [N]ACK_PREP from + * other machines. Read image (including atomic restore) until done. + * Wait for ACK_READ from others (should never fail). Thaw processes + * and do post-resume. (The section after the atomic restore is done + * via the code for hibernating). + */ + + node_array[0].current_message = MSG_RUNNING; +} + +/* toi_cluster_open_iface + * + * Description: Prepare to use an interface. + */ + +static int toi_cluster_open_iface(void) +{ + struct net_device *dev; + + rtnl_lock(); + + for_each_netdev(&init_net, dev) { + if (/* dev == &init_net.loopback_dev || */ + strcmp(dev->name, toi_cluster_iface)) + continue; + + net_dev = dev; + break; + } + + rtnl_unlock(); + + if (!net_dev) { + printk(KERN_ERR MYNAME ": Device %s not found.\n", + toi_cluster_iface); + return -ENODEV; + } + + dev_add_pack(&toi_cluster_packet_type); + added_pack = 1; + + loopback_mode = (net_dev == init_net.loopback_dev); + num_local_nodes = loopback_mode ? 8 : 1; + + PRINTK("Loopback mode is %s. Number of local nodes is %d.\n", + loopback_mode ? "on" : "off", num_local_nodes); + + cluster_startup(); + return 0; +} + +/* toi_cluster_close_iface + * + * Description: Stop using an interface. + */ + +static int toi_cluster_close_iface(void) +{ + kill_clusterd(); + if (added_pack) { + dev_remove_pack(&toi_cluster_packet_type); + added_pack = 0; + } + return 0; +} + +static void write_side_effect(void) +{ + if (toi_cluster_ops.enabled) { + toi_cluster_open_iface(); + set_toi_state(TOI_CLUSTER_MODE); + } else { + toi_cluster_close_iface(); + clear_toi_state(TOI_CLUSTER_MODE); + } +} + +static void node_write_side_effect(void) +{ +} + +/* + * data for our sysfs entries. + */ +static struct toi_sysfs_data sysfs_params[] = { + SYSFS_STRING("interface", SYSFS_RW, toi_cluster_iface, IFNAMSIZ, 0, + NULL), + SYSFS_INT("enabled", SYSFS_RW, &toi_cluster_ops.enabled, 0, 1, 0, + write_side_effect), + SYSFS_STRING("cluster_name", SYSFS_RW, toi_cluster_key, 32, 0, NULL), + SYSFS_STRING("pre-hibernate-script", SYSFS_RW, pre_hibernate_script, + 256, 0, NULL), + SYSFS_STRING("post-hibernate-script", SYSFS_RW, post_hibernate_script, + 256, 0, STRING), + SYSFS_UL("continue_delay", SYSFS_RW, &continue_delay, HZ / 2, 60 * HZ, + 0) +}; + +/* + * Ops structure. + */ + +static struct toi_module_ops toi_cluster_ops = { + .type = FILTER_MODULE, + .name = "Cluster", + .directory = "cluster", + .module = THIS_MODULE, + .memory_needed = toi_cluster_memory_needed, + .print_debug_info = toi_cluster_print_debug_stats, + .save_config_info = toi_cluster_save_config_info, + .load_config_info = toi_cluster_load_config_info, + .storage_needed = toi_cluster_storage_needed, + + .sysfs_data = sysfs_params, + .num_sysfs_entries = sizeof(sysfs_params) / + sizeof(struct toi_sysfs_data), +}; + +/* ---- Registration ---- */ + +#ifdef MODULE +#define INIT static __init +#define EXIT static __exit +#else +#define INIT +#define EXIT +#endif + +INIT int toi_cluster_init(void) +{ + int temp = toi_register_module(&toi_cluster_ops), i; + struct kobject *kobj = toi_cluster_ops.dir_kobj; + + for (i = 0; i < MAX_LOCAL_NODES; i++) { + node_array[i].current_message = 0; + INIT_LIST_HEAD(&node_array[i].member_list); + init_waitqueue_head(&node_array[i].member_events); + spin_lock_init(&node_array[i].member_list_lock); + spin_lock_init(&node_array[i].receive_lock); + + /* Set up sysfs entry */ + node_array[i].sysfs_data.attr.name = toi_kzalloc(8, + sizeof(node_array[i].sysfs_data.attr.name), + GFP_KERNEL); + sprintf((char *) node_array[i].sysfs_data.attr.name, "node_%d", + i); + node_array[i].sysfs_data.attr.mode = SYSFS_RW; + node_array[i].sysfs_data.type = TOI_SYSFS_DATA_INTEGER; + node_array[i].sysfs_data.flags = 0; + node_array[i].sysfs_data.data.integer.variable = + (int *) &node_array[i].current_message; + node_array[i].sysfs_data.data.integer.minimum = 0; + node_array[i].sysfs_data.data.integer.maximum = INT_MAX; + node_array[i].sysfs_data.write_side_effect = + node_write_side_effect; + toi_register_sysfs_file(kobj, &node_array[i].sysfs_data); + } + + toi_cluster_ops.enabled = (strlen(toi_cluster_iface) > 0); + + if (toi_cluster_ops.enabled) + toi_cluster_open_iface(); + + return temp; +} + +EXIT void toi_cluster_exit(void) +{ + int i; + toi_cluster_close_iface(); + + for (i = 0; i < MAX_LOCAL_NODES; i++) + toi_unregister_sysfs_file(toi_cluster_ops.dir_kobj, + &node_array[i].sysfs_data); + toi_unregister_module(&toi_cluster_ops); +} + +static int __init toi_cluster_iface_setup(char *iface) +{ + toi_cluster_ops.enabled = (*iface && + strcmp(iface, "off")); + + if (toi_cluster_ops.enabled) + strncpy(toi_cluster_iface, iface, strlen(iface)); +} + +__setup("toi_cluster=", toi_cluster_iface_setup); |