#include <linux/types.h> #include <linux/atmmpc.h> #include <linux/slab.h> #include <linux/time.h> #include "mpoa_caches.h" #include "mpc.h" /* * mpoa_caches.c: Implementation of ingress and egress cache * handling functions */ #if 0 #define dprintk(format, args...) \ printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args) /* debug */ #else #define dprintk(format, args...) \ do { if (0) \ printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args);\ } while (0) #endif #if 0 #define ddprintk(format, args...) \ printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args) /* debug */ #else #define ddprintk(format, args...) \ do { if (0) \ printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args);\ } while (0) #endif static in_cache_entry *in_cache_get(__be32 dst_ip, struct mpoa_client *client) { in_cache_entry *entry; read_lock_bh(&client->ingress_lock); entry = client->in_cache; while (entry != NULL) { if (entry->ctrl_info.in_dst_ip == dst_ip) { atomic_inc(&entry->use); read_unlock_bh(&client->ingress_lock); return entry; } entry = entry->next; } read_unlock_bh(&client->ingress_lock); return NULL; } static in_cache_entry *in_cache_get_with_mask(__be32 dst_ip, struct mpoa_client *client, __be32 mask) { in_cache_entry *entry; read_lock_bh(&client->ingress_lock); entry = client->in_cache; while (entry != NULL) { if ((entry->ctrl_info.in_dst_ip & mask) == (dst_ip & mask)) { atomic_inc(&entry->use); read_unlock_bh(&client->ingress_lock); return entry; } entry = entry->next; } read_unlock_bh(&client->ingress_lock); return NULL; } static in_cache_entry *in_cache_get_by_vcc(struct atm_vcc *vcc, struct mpoa_client *client) { in_cache_entry *entry; read_lock_bh(&client->ingress_lock); entry = client->in_cache; while (entry != NULL) { if (entry->shortcut == vcc) { atomic_inc(&entry->use); read_unlock_bh(&client->ingress_lock); return entry; } entry = entry->next; } read_unlock_bh(&client->ingress_lock); return NULL; } static in_cache_entry *in_cache_add_entry(__be32 dst_ip, struct mpoa_client *client) { in_cache_entry *entry = kzalloc(sizeof(in_cache_entry), GFP_KERNEL); if (entry == NULL) { pr_info("mpoa: mpoa_caches.c: new_in_cache_entry: out of memory\n"); return NULL; } dprintk("adding an ingress entry, ip = %pI4\n", &dst_ip); atomic_set(&entry->use, 1); dprintk("new_in_cache_entry: about to lock\n"); write_lock_bh(&client->ingress_lock); entry->next = client->in_cache; entry->prev = NULL; if (client->in_cache != NULL) client->in_cache->prev = entry; client->in_cache = entry; memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN); entry->ctrl_info.in_dst_ip = dst_ip; do_gettimeofday(&(entry->tv)); entry->retry_time = client->parameters.mpc_p4; entry->count = 1; entry->entry_state = INGRESS_INVALID; entry->ctrl_info.holding_time = HOLDING_TIME_DEFAULT; atomic_inc(&entry->use); write_unlock_bh(&client->ingress_lock); dprintk("new_in_cache_entry: unlocked\n"); return entry; } static int cache_hit(in_cache_entry *entry, struct mpoa_client *mpc) { struct atm_mpoa_qos *qos; struct k_message msg; entry->count++; if (entry->entry_state == INGRESS_RESOLVED && entry->shortcut != NULL) return OPEN; if (entry->entry_state == INGRESS_REFRESHING) { if (entry->count > mpc->parameters.mpc_p1) { msg.type = SND_MPOA_RES_RQST; msg.content.in_info = entry->ctrl_info; memcpy(msg.MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN); qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip); if (qos != NULL) msg.qos = qos->qos; msg_to_mpoad(&msg, mpc); do_gettimeofday(&(entry->reply_wait)); entry->entry_state = INGRESS_RESOLVING; } if (entry->shortcut != NULL) return OPEN; return CLOSED; } if (entry->entry_state == INGRESS_RESOLVING && entry->shortcut != NULL) return OPEN; if (entry->count > mpc->parameters.mpc_p1 && entry->entry_state == INGRESS_INVALID) { dprintk("(%s) threshold exceeded for ip %pI4, sending MPOA res req\n", mpc->dev->name, &entry->ctrl_info.in_dst_ip); entry->entry_state = INGRESS_RESOLVING; msg.type = SND_MPOA_RES_RQST; memcpy(msg.MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN); msg.content.in_info = entry->ctrl_info; qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip); if (qos != NULL) msg.qos = qos->qos; msg_to_mpoad(&msg, mpc); do_gettimeofday(&(entry->reply_wait)); } return CLOSED; } static void in_cache_put(in_cache_entry *entry) { if (atomic_dec_and_test(&entry->use)) { memset(entry, 0, sizeof(in_cache_entry)); kfree(entry); } } /* * This should be called with write lock on */ static void in_cache_remove_entry(in_cache_entry *entry, struct mpoa_client *client) { struct atm_vcc *vcc; struct k_message msg; vcc = entry->shortcut; dprintk("removing an ingress entry, ip = %pI4\n", &entry->ctrl_info.in_dst_ip); if (entry->prev != NULL) entry->prev->next = entry->next; else client->in_cache = entry->next; if (entry->next != NULL) entry->next->prev = entry->prev; client->in_ops->put(entry); if (client->in_cache == NULL && client->eg_cache == NULL) { msg.type = STOP_KEEP_ALIVE_SM; msg_to_mpoad(&msg, client); } /* Check if the egress side still uses this VCC */ if (vcc != NULL) { eg_cache_entry *eg_entry = client->eg_ops->get_by_vcc(vcc, client); if (eg_entry != NULL) { client->eg_ops->put(eg_entry); return; } vcc_release_async(vcc, -EPIPE); } } /* Call this every MPC-p2 seconds... Not exactly correct solution, but an easy one... */ static void clear_count_and_expired(struct mpoa_client *client) { in_cache_entry *entry, *next_entry; struct timeval now; do_gettimeofday(&now); write_lock_bh(&client->ingress_lock); entry = client->in_cache; while (entry != NULL) { entry->count = 0; next_entry = entry->next; if ((now.tv_sec - entry->tv.tv_sec) > entry->ctrl_info.holding_time) { dprintk("holding time expired, ip = %pI4\n", &entry->ctrl_info.in_dst_ip); client->in_ops->remove_entry(entry, client); } entry = next_entry; } write_unlock_bh(&client->ingress_lock); } /* Call this every MPC-p4 seconds. */ static void check_resolving_entries(struct mpoa_client *client) { struct atm_mpoa_qos *qos; in_cache_entry *entry; struct timeval now; struct k_message msg; do_gettimeofday(&now); read_lock_bh(&client->ingress_lock); entry = client->in_cache; while (entry != NULL) { if (entry->entry_state == INGRESS_RESOLVING) { if ((now.tv_sec - entry->hold_down.tv_sec) < client->parameters.mpc_p6) { entry = entry->next; /* Entry in hold down */ continue; } if ((now.tv_sec - entry->reply_wait.tv_sec) > entry->retry_time) { entry->retry_time = MPC_C1 * (entry->retry_time); /* * Retry time maximum exceeded, * put entry in hold down. */ if (entry->retry_time > client->parameters.mpc_p5) { do_gettimeofday(&(entry->hold_down)); entry->retry_time = client->parameters.mpc_p4; entry = entry->next; continue; } /* Ask daemon to send a resolution request. */ memset(&(entry->hold_down), 0, sizeof(struct timeval)); msg.type = SND_MPOA_RES_RTRY; memcpy(msg.MPS_ctrl, client->mps_ctrl_addr, ATM_ESA_LEN); msg.content.in_info = entry->ctrl_info; qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip); if (qos != NULL) msg.qos = qos->qos; msg_to_mpoad(&msg, client); do_gettimeofday(&(entry->reply_wait)); } } entry = entry->next; } read_unlock_bh(&client->ingress_lock); } /* Call this every MPC-p5 seconds. */ static void refresh_entries(struct mpoa_client *client) { struct timeval now; struct in_cache_entry *entry = client->in_cache; ddprintk("refresh_entries\n"); do_gettimeofday(&now); read_lock_bh(&client->ingress_lock); while (entry != NULL) { if (entry->entry_state == INGRESS_RESOLVED) { if (!(entry->refresh_time)) entry->refresh_time = (2 * (entry->ctrl_info.holding_time))/3; if ((now.tv_sec - entry->reply_wait.tv_sec) > entry->refresh_time) { dprintk("refreshing an entry.\n"); entry->entry_state = INGRESS_REFRESHING; } } entry = entry->next; } read_unlock_bh(&client->ingress_lock); } static void in_destroy_cache(struct mpoa_client *mpc) { write_lock_irq(&mpc->ingress_lock); while (mpc->in_cache != NULL) mpc->in_ops->remove_entry(mpc->in_cache, mpc); write_unlock_irq(&mpc->ingress_lock); } static eg_cache_entry *eg_cache_get_by_cache_id(__be32 cache_id, struct mpoa_client *mpc) { eg_cache_entry *entry; read_lock_irq(&mpc->egress_lock); entry = mpc->eg_cache; while (entry != NULL) { if (entry->ctrl_info.cache_id == cache_id) { atomic_inc(&entry->use); read_unlock_irq(&mpc->egress_lock); return entry; } entry = entry->next; } read_unlock_irq(&mpc->egress_lock); return NULL; } /* This can be called from any context since it saves CPU flags */ static eg_cache_entry *eg_cache_get_by_tag(__be32 tag, struct mpoa_client *mpc) { unsigned long flags; eg_cache_entry *entry; read_lock_irqsave(&mpc->egress_lock, flags); entry = mpc->eg_cache; while (entry != NULL) { if (entry->ctrl_info.tag == tag) { atomic_inc(&entry->use); read_unlock_irqrestore(&mpc->egress_lock, flags); return entry; } entry = entry->next; } read_unlock_irqrestore(&mpc->egress_lock, flags); return NULL; } /* This can be called from any context since it saves CPU flags */ static eg_cache_entry *eg_cache_get_by_vcc(struct atm_vcc *vcc, struct mpoa_client *mpc) { unsigned long flags; eg_cache_entry *entry; read_lock_irqsave(&mpc->egress_lock, flags); entry = mpc->eg_cache; while (entry != NULL) { if (entry->shortcut == vcc) { atomic_inc(&entry->use); read_unlock_irqrestore(&mpc->egress_lock, flags); return entry; } entry = entry->next; } read_unlock_irqrestore(&mpc->egress_lock, flags); return NULL; } static eg_cache_entry *eg_cache_get_by_src_ip(__be32 ipaddr, struct mpoa_client *mpc) { eg_cache_entry *entry; read_lock_irq(&mpc->egress_lock); entry = mpc->eg_cache; while (entry != NULL) { if (entry->latest_ip_addr == ipaddr) { atomic_inc(&entry->use); read_unlock_irq(&mpc->egress_lock); return entry; } entry = entry->next; } read_unlock_irq(&mpc->egress_lock); return NULL; } static void eg_cache_put(eg_cache_entry *entry) { if (atomic_dec_and_test(&entry->use)) { memset(entry, 0, sizeof(eg_cache_entry)); kfree(entry); } } /* * This should be called with write lock on */ static void eg_cache_remove_entry(eg_cache_entry *entry, struct mpoa_client *client) { struct atm_vcc *vcc; struct k_message msg; vcc = entry->shortcut; dprintk("removing an egress entry.\n"); if (entry->prev != NULL) entry->prev->next = entry->next; else client->eg_cache = entry->next; if (entry->next != NULL) entry->next->prev = entry->prev; client->eg_ops->put(entry); if (client->in_cache == NULL && client->eg_cache == NULL) { msg.type = STOP_KEEP_ALIVE_SM; msg_to_mpoad(&msg, client); } /* Check if the ingress side still uses this VCC */ if (vcc != NULL) { in_cache_entry *in_entry = client->in_ops->get_by_vcc(vcc, client); if (in_entry != NULL) { client->in_ops->put(in_entry); return; } vcc_release_async(vcc, -EPIPE); } } static eg_cache_entry *eg_cache_add_entry(struct k_message *msg, struct mpoa_client *client) { eg_cache_entry *entry = kzalloc(sizeof(eg_cache_entry), GFP_KERNEL); if (entry == NULL) { pr_info("out of memory\n"); return NULL; } dprintk("adding an egress entry, ip = %pI4, this should be our IP\n", &msg->content.eg_info.eg_dst_ip); atomic_set(&entry->use, 1); dprintk("new_eg_cache_entry: about to lock\n"); write_lock_irq(&client->egress_lock); entry->next = client->eg_cache; entry->prev = NULL; if (client->eg_cache != NULL) client->eg_cache->prev = entry; client->eg_cache = entry; memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN); entry->ctrl_info = msg->content.eg_info; do_gettimeofday(&(entry->tv)); entry->entry_state = EGRESS_RESOLVED; dprintk("new_eg_cache_entry cache_id %u\n", ntohl(entry->ctrl_info.cache_id)); dprintk("mps_ip = %pI4\n", &entry->ctrl_info.mps_ip); atomic_inc(&entry->use); write_unlock_irq(&client->egress_lock); dprintk("new_eg_cache_entry: unlocked\n"); return entry; } static void update_eg_cache_entry(eg_cache_entry *entry, uint16_t holding_time) { do_gettimeofday(&(entry->tv)); entry->entry_state = EGRESS_RESOLVED; entry->ctrl_info.holding_time = holding_time; } static void clear_expired(struct mpoa_client *client) { eg_cache_entry *entry, *next_entry; struct timeval now; struct k_message msg; do_gettimeofday(&now); write_lock_irq(&client->egress_lock); entry = client->eg_cache; while (entry != NULL) { next_entry = entry->next; if ((now.tv_sec - entry->tv.tv_sec) > entry->ctrl_info.holding_time) { msg.type = SND_EGRESS_PURGE; msg.content.eg_info = entry->ctrl_info; dprintk("egress_cache: holding time expired, cache_id = %u.\n", ntohl(entry->ctrl_info.cache_id)); msg_to_mpoad(&msg, client); client->eg_ops->remove_entry(entry, client); } entry = next_entry; } write_unlock_irq(&client->egress_lock); } static void eg_destroy_cache(struct mpoa_client *mpc) { write_lock_irq(&mpc->egress_lock); while (mpc->eg_cache != NULL) mpc->eg_ops->remove_entry(mpc->eg_cache, mpc); write_unlock_irq(&mpc->egress_lock); } static const struct in_cache_ops ingress_ops = { in_cache_add_entry, /* add_entry */ in_cache_get, /* get */ in_cache_get_with_mask, /* get_with_mask */ in_cache_get_by_vcc, /* get_by_vcc */ in_cache_put, /* put */ in_cache_remove_entry, /* remove_entry */ cache_hit, /* cache_hit */ clear_count_and_expired, /* clear_count */ check_resolving_entries, /* check_resolving */ refresh_entries, /* refresh */ in_destroy_cache /* destroy_cache */ }; static const struct eg_cache_ops egress_ops = { eg_cache_add_entry, /* add_entry */ eg_cache_get_by_cache_id, /* get_by_cache_id */ eg_cache_get_by_tag, /* get_by_tag */ eg_cache_get_by_vcc, /* get_by_vcc */ eg_cache_get_by_src_ip, /* get_by_src_ip */ eg_cache_put, /* put */ eg_cache_remove_entry, /* remove_entry */ update_eg_cache_entry, /* update */ clear_expired, /* clear_expired */ eg_destroy_cache /* destroy_cache */ }; void atm_mpoa_init_cache(struct mpoa_client *mpc) { mpc->in_ops = &ingress_ops; mpc->eg_ops = &egress_ops; }