v4.19.13 snapshot.
diff --git a/net/atm/mpoa_caches.c b/net/atm/mpoa_caches.c
new file mode 100644
index 0000000..4bb4183
--- /dev/null
+++ b/net/atm/mpoa_caches.c
@@ -0,0 +1,567 @@
+// SPDX-License-Identifier: GPL-2.0
+#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) {
+ refcount_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)) {
+ refcount_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) {
+ refcount_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);
+
+ refcount_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;
+ entry->time = ktime_get_seconds();
+ entry->retry_time = client->parameters.mpc_p4;
+ entry->count = 1;
+ entry->entry_state = INGRESS_INVALID;
+ entry->ctrl_info.holding_time = HOLDING_TIME_DEFAULT;
+ refcount_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);
+ entry->reply_wait = ktime_get_seconds();
+ 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);
+ entry->reply_wait = ktime_get_seconds();
+ }
+
+ return CLOSED;
+}
+
+static void in_cache_put(in_cache_entry *entry)
+{
+ if (refcount_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;
+ time64_t now;
+
+ now = ktime_get_seconds();
+
+ write_lock_bh(&client->ingress_lock);
+ entry = client->in_cache;
+ while (entry != NULL) {
+ entry->count = 0;
+ next_entry = entry->next;
+ if ((now - entry->time) > 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;
+ time64_t now;
+ struct k_message msg;
+
+ now = ktime_get_seconds();
+
+ read_lock_bh(&client->ingress_lock);
+ entry = client->in_cache;
+ while (entry != NULL) {
+ if (entry->entry_state == INGRESS_RESOLVING) {
+
+ if ((now - entry->hold_down)
+ < client->parameters.mpc_p6) {
+ entry = entry->next; /* Entry in hold down */
+ continue;
+ }
+ if ((now - entry->reply_wait) > 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) {
+ entry->hold_down = ktime_get_seconds();
+ entry->retry_time = client->parameters.mpc_p4;
+ entry = entry->next;
+ continue;
+ }
+ /* Ask daemon to send a resolution request. */
+ memset(&entry->hold_down, 0, sizeof(time64_t));
+ 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);
+ entry->reply_wait = ktime_get_seconds();
+ }
+ }
+ entry = entry->next;
+ }
+ read_unlock_bh(&client->ingress_lock);
+}
+
+/* Call this every MPC-p5 seconds. */
+static void refresh_entries(struct mpoa_client *client)
+{
+ time64_t now;
+ struct in_cache_entry *entry = client->in_cache;
+
+ ddprintk("refresh_entries\n");
+ now = ktime_get_seconds();
+
+ 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 - entry->reply_wait) >
+ 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) {
+ refcount_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) {
+ refcount_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) {
+ refcount_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) {
+ refcount_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 (refcount_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);
+
+ refcount_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;
+ entry->time = ktime_get_seconds();
+ 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);
+ refcount_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)
+{
+ entry->time = ktime_get_seconds();
+ 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;
+ time64_t now;
+ struct k_message msg;
+
+ now = ktime_get_seconds();
+
+ write_lock_irq(&client->egress_lock);
+ entry = client->eg_cache;
+ while (entry != NULL) {
+ next_entry = entry->next;
+ if ((now - entry->time) > 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 = {
+ .add_entry = in_cache_add_entry,
+ .get = in_cache_get,
+ .get_with_mask = in_cache_get_with_mask,
+ .get_by_vcc = in_cache_get_by_vcc,
+ .put = in_cache_put,
+ .remove_entry = in_cache_remove_entry,
+ .cache_hit = cache_hit,
+ .clear_count = clear_count_and_expired,
+ .check_resolving = check_resolving_entries,
+ .refresh = refresh_entries,
+ .destroy_cache = in_destroy_cache
+};
+
+static const struct eg_cache_ops egress_ops = {
+ .add_entry = eg_cache_add_entry,
+ .get_by_cache_id = eg_cache_get_by_cache_id,
+ .get_by_tag = eg_cache_get_by_tag,
+ .get_by_vcc = eg_cache_get_by_vcc,
+ .get_by_src_ip = eg_cache_get_by_src_ip,
+ .put = eg_cache_put,
+ .remove_entry = eg_cache_remove_entry,
+ .update = update_eg_cache_entry,
+ .clear_expired = clear_expired,
+ .destroy_cache = eg_destroy_cache
+};
+
+void atm_mpoa_init_cache(struct mpoa_client *mpc)
+{
+ mpc->in_ops = &ingress_ops;
+ mpc->eg_ops = &egress_ops;
+}