ipv6: ip6mr: convert struct mfc_cache to struct list_head

Signed-off-by: Patrick McHardy <kaber@trash.net>

1 files changed, 62 insertions, 65 deletions

diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index b3783a436bbd..08e09042ad1c 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -89,7 +89,7 @@ static void mroute_clean_tables(struct net *net);
 
 struct ipmr_mfc_iter {
         struct seq_net_private p;
-        struct mfc6_cache **cache;
+        struct list_head *cache;
         int ct;
 };
 
@@ -99,18 +99,18 @@ static struct mfc6_cache *ipmr_mfc_seq_idx(struct net *net,
 {
         struct mfc6_cache *mfc;
 
-        it->cache = net->ipv6.mfc6_cache_array;
         read_lock(&mrt_lock);
-        for (it->ct = 0; it->ct < MFC6_LINES; it->ct++)
-                for (mfc = net->ipv6.mfc6_cache_array[it->ct];
-                     mfc; mfc = mfc->next)
+        for (it->ct = 0; it->ct < MFC6_LINES; it->ct++) {
+                it->cache = &net->ipv6.mfc6_cache_array[it->ct];
+                list_for_each_entry(mfc, it->cache, list)
                         if (pos-- == 0)
                                 return mfc;
+        }
         read_unlock(&mrt_lock);
 
-        it->cache = &net->ipv6.mfc6_unres_queue;
         spin_lock_bh(&mfc_unres_lock);
-        for (mfc = net->ipv6.mfc6_unres_queue; mfc; mfc = mfc->next)
+        it->cache = &net->ipv6.mfc6_unres_queue;
+        list_for_each_entry(mfc, it->cache, list)
                 if (pos-- == 0)
                         return mfc;
         spin_unlock_bh(&mfc_unres_lock);
@@ -119,9 +119,6 @@ static struct mfc6_cache *ipmr_mfc_seq_idx(struct net *net,
         return NULL;
 }
 
-
-
-
 /*
  *      The /proc interfaces to multicast routing /proc/ip6_mr_cache /proc/ip6_mr_vif
  */
@@ -238,18 +235,19 @@ static void *ipmr_mfc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
         if (v == SEQ_START_TOKEN)
                 return ipmr_mfc_seq_idx(net, seq->private, 0);
 
-        if (mfc->next)
-                return mfc->next;
+        if (mfc->list.next != it->cache)
+                return list_entry(mfc->list.next, struct mfc6_cache, list);
 
         if (it->cache == &net->ipv6.mfc6_unres_queue)
                 goto end_of_list;
 
-        BUG_ON(it->cache != net->ipv6.mfc6_cache_array);
+        BUG_ON(it->cache != &net->ipv6.mfc6_cache_array[it->ct]);
 
         while (++it->ct < MFC6_LINES) {
-                mfc = net->ipv6.mfc6_cache_array[it->ct];
-                if (mfc)
-                        return mfc;
+                it->cache = &net->ipv6.mfc6_cache_array[it->ct];
+                if (list_empty(it->cache))
+                        continue;
+                return list_first_entry(it->cache, struct mfc6_cache, list);
         }
 
         /* exhausted cache_array, show unresolved */
@@ -258,9 +256,8 @@ static void *ipmr_mfc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
         it->ct = 0;
 
         spin_lock_bh(&mfc_unres_lock);
-        mfc = net->ipv6.mfc6_unres_queue;
-        if (mfc)
-                return mfc;
+        if (!list_empty(it->cache))
+                return list_first_entry(it->cache, struct mfc6_cache, list);
 
  end_of_list:
         spin_unlock_bh(&mfc_unres_lock);
@@ -560,25 +557,22 @@ static void ipmr_do_expire_process(struct net *net)
 {
         unsigned long now = jiffies;
         unsigned long expires = 10 * HZ;
-        struct mfc6_cache *c, **cp;
-
-        cp = &net->ipv6.mfc6_unres_queue;
+        struct mfc6_cache *c, *next;
 
-        while ((c = *cp) != NULL) {
+        list_for_each_entry_safe(c, next, &net->ipv6.mfc6_unres_queue, list) {
                 if (time_after(c->mfc_un.unres.expires, now)) {
                         /* not yet... */
                         unsigned long interval = c->mfc_un.unres.expires - now;
                         if (interval < expires)
                                 expires = interval;
-                        cp = &c->next;
                         continue;
                 }
 
-                *cp = c->next;
+                list_del(&c->list);
                 ip6mr_destroy_unres(net, c);
         }
 
-        if (net->ipv6.mfc6_unres_queue != NULL)
+        if (!list_empty(&net->ipv6.mfc6_unres_queue))
                 mod_timer(&net->ipv6.ipmr_expire_timer, jiffies + expires);
 }
 
@@ -591,7 +585,7 @@ static void ipmr_expire_process(unsigned long arg)
                 return;
         }
 
-        if (net->ipv6.mfc6_unres_queue != NULL)
+        if (!list_empty(&net->ipv6.mfc6_unres_queue))
                 ipmr_do_expire_process(net);
 
         spin_unlock(&mfc_unres_lock);
@@ -706,12 +700,12 @@ static struct mfc6_cache *ip6mr_cache_find(struct net *net,
         int line = MFC6_HASH(mcastgrp, origin);
         struct mfc6_cache *c;
 
-        for (c = net->ipv6.mfc6_cache_array[line]; c; c = c->next) {
+        list_for_each_entry(c, &net->ipv6.mfc6_cache_array[line], list) {
                 if (ipv6_addr_equal(&c->mf6c_origin, origin) &&
                     ipv6_addr_equal(&c->mf6c_mcastgrp, mcastgrp))
-                        break;
+                        return c;
         }
-        return c;
+        return NULL;
 }
 
 /*
@@ -872,17 +866,20 @@ static int ip6mr_cache_report(struct net *net, struct sk_buff *pkt, mifi_t mifi,
 static int
 ip6mr_cache_unresolved(struct net *net, mifi_t mifi, struct sk_buff *skb)
 {
+        bool found = false;
         int err;
         struct mfc6_cache *c;
 
         spin_lock_bh(&mfc_unres_lock);
-        for (c = net->ipv6.mfc6_unres_queue; c; c = c->next) {
+        list_for_each_entry(c, &net->ipv6.mfc6_unres_queue, list) {
                 if (ipv6_addr_equal(&c->mf6c_mcastgrp, &ipv6_hdr(skb)->daddr) &&
-                    ipv6_addr_equal(&c->mf6c_origin, &ipv6_hdr(skb)->saddr))
+                    ipv6_addr_equal(&c->mf6c_origin, &ipv6_hdr(skb)->saddr)) {
+                        found = true;
                         break;
+                }
         }
 
-        if (c == NULL) {
+        if (!found) {
                 /*
                  *      Create a new entry if allowable
                  */
@@ -918,8 +915,7 @@ ip6mr_cache_unresolved(struct net *net, mifi_t mifi, struct sk_buff *skb)
                 }
 
                 atomic_inc(&net->ipv6.cache_resolve_queue_len);
-                c->next = net->ipv6.mfc6_unres_queue;
-                net->ipv6.mfc6_unres_queue = c;
+                list_add(&c->list, &net->ipv6.mfc6_unres_queue);
 
                 ipmr_do_expire_process(net);
         }
@@ -946,16 +942,15 @@ ip6mr_cache_unresolved(struct net *net, mifi_t mifi, struct sk_buff *skb)
 static int ip6mr_mfc_delete(struct net *net, struct mf6cctl *mfc)
 {
         int line;
-        struct mfc6_cache *c, **cp;
+        struct mfc6_cache *c, *next;
 
         line = MFC6_HASH(&mfc->mf6cc_mcastgrp.sin6_addr, &mfc->mf6cc_origin.sin6_addr);
 
-        for (cp = &net->ipv6.mfc6_cache_array[line];
-             (c = *cp) != NULL; cp = &c->next) {
+        list_for_each_entry_safe(c, next, &net->ipv6.mfc6_cache_array[line], list) {
                 if (ipv6_addr_equal(&c->mf6c_origin, &mfc->mf6cc_origin.sin6_addr) &&
                     ipv6_addr_equal(&c->mf6c_mcastgrp, &mfc->mf6cc_mcastgrp.sin6_addr)) {
                         write_lock_bh(&mrt_lock);
-                        *cp = c->next;
+                        list_del(&c->list);
                         write_unlock_bh(&mrt_lock);
 
                         ip6mr_cache_free(c);
@@ -997,7 +992,9 @@ static struct notifier_block ip6_mr_notifier = {
 
 static int __net_init ip6mr_net_init(struct net *net)
 {
+        unsigned int i;
         int err = 0;
+
         net->ipv6.vif6_table = kcalloc(MAXMIFS, sizeof(struct mif_device),
                                        GFP_KERNEL);
         if (!net->ipv6.vif6_table) {
@@ -1007,13 +1004,18 @@ static int __net_init ip6mr_net_init(struct net *net)
 
         /* Forwarding cache */
         net->ipv6.mfc6_cache_array = kcalloc(MFC6_LINES,
-                                             sizeof(struct mfc6_cache *),
+                                             sizeof(struct list_head),
                                              GFP_KERNEL);
         if (!net->ipv6.mfc6_cache_array) {
                 err = -ENOMEM;
                 goto fail_mfc6_cache;
         }
 
+        for (i = 0; i < MFC6_LINES; i++)
+                INIT_LIST_HEAD(&net->ipv6.mfc6_cache_array[i]);
+
+        INIT_LIST_HEAD(&net->ipv6.mfc6_unres_queue);
+
         setup_timer(&net->ipv6.ipmr_expire_timer, ipmr_expire_process,
                     (unsigned long)net);
 
@@ -1105,8 +1107,9 @@ void ip6_mr_cleanup(void)
 
 static int ip6mr_mfc_add(struct net *net, struct mf6cctl *mfc, int mrtsock)
 {
+        bool found = false;
         int line;
-        struct mfc6_cache *uc, *c, **cp;
+        struct mfc6_cache *uc, *c;
         unsigned char ttls[MAXMIFS];
         int i;
 
@@ -1122,14 +1125,15 @@ static int ip6mr_mfc_add(struct net *net, struct mf6cctl *mfc, int mrtsock)
 
         line = MFC6_HASH(&mfc->mf6cc_mcastgrp.sin6_addr, &mfc->mf6cc_origin.sin6_addr);
 
-        for (cp = &net->ipv6.mfc6_cache_array[line];
-             (c = *cp) != NULL; cp = &c->next) {
+        list_for_each_entry(c, &net->ipv6.mfc6_cache_array[line], list) {
                 if (ipv6_addr_equal(&c->mf6c_origin, &mfc->mf6cc_origin.sin6_addr) &&
-                    ipv6_addr_equal(&c->mf6c_mcastgrp, &mfc->mf6cc_mcastgrp.sin6_addr))
+                    ipv6_addr_equal(&c->mf6c_mcastgrp, &mfc->mf6cc_mcastgrp.sin6_addr)) {
+                        found = true;
                         break;
+                }
         }
 
-        if (c != NULL) {
+        if (found) {
                 write_lock_bh(&mrt_lock);
                 c->mf6c_parent = mfc->mf6cc_parent;
                 ip6mr_update_thresholds(net, c, ttls);
@@ -1154,29 +1158,29 @@ static int ip6mr_mfc_add(struct net *net, struct mf6cctl *mfc, int mrtsock)
                 c->mfc_flags |= MFC_STATIC;
 
         write_lock_bh(&mrt_lock);
-        c->next = net->ipv6.mfc6_cache_array[line];
-        net->ipv6.mfc6_cache_array[line] = c;
+        list_add(&c->list, &net->ipv6.mfc6_cache_array[line]);
         write_unlock_bh(&mrt_lock);
 
         /*
          *      Check to see if we resolved a queued list. If so we
          *      need to send on the frames and tidy up.
          */
+        found = false;
         spin_lock_bh(&mfc_unres_lock);
-        for (cp = &net->ipv6.mfc6_unres_queue; (uc = *cp) != NULL;
-             cp = &uc->next) {
+        list_for_each_entry(uc, &net->ipv6.mfc6_unres_queue, list) {
                 if (ipv6_addr_equal(&uc->mf6c_origin, &c->mf6c_origin) &&
                     ipv6_addr_equal(&uc->mf6c_mcastgrp, &c->mf6c_mcastgrp)) {
-                        *cp = uc->next;
+                        list_del(&uc->list);
                         atomic_dec(&net->ipv6.cache_resolve_queue_len);
+                        found = true;
                         break;
                 }
         }
-        if (net->ipv6.mfc6_unres_queue == NULL)
+        if (list_empty(&net->ipv6.mfc6_unres_queue))
                 del_timer(&net->ipv6.ipmr_expire_timer);
         spin_unlock_bh(&mfc_unres_lock);
 
-        if (uc) {
+        if (found) {
                 ip6mr_cache_resolve(net, uc, c);
                 ip6mr_cache_free(uc);
         }
@@ -1191,6 +1195,7 @@ static void mroute_clean_tables(struct net *net)
 {
         int i;
         LIST_HEAD(list);
+        struct mfc6_cache *c, *next;
 
         /*
          *      Shut down all active vif entries
@@ -1205,16 +1210,11 @@ static void mroute_clean_tables(struct net *net)
          *      Wipe the cache
          */
         for (i = 0; i < MFC6_LINES; i++) {
-                struct mfc6_cache *c, **cp;
-
-                cp = &net->ipv6.mfc6_cache_array[i];
-                while ((c = *cp) != NULL) {
-                        if (c->mfc_flags & MFC_STATIC) {
-                                cp = &c->next;
+                list_for_each_entry_safe(c, next, &net->ipv6.mfc6_cache_array[i], list) {
+                        if (c->mfc_flags & MFC_STATIC)
                                 continue;
-                        }
                         write_lock_bh(&mrt_lock);
-                        *cp = c->next;
+                        list_del(&c->list);
                         write_unlock_bh(&mrt_lock);
 
                         ip6mr_cache_free(c);
@@ -1222,12 +1222,9 @@ static void mroute_clean_tables(struct net *net)
         }
 
         if (atomic_read(&net->ipv6.cache_resolve_queue_len) != 0) {
-                struct mfc6_cache *c, **cp;
-
                 spin_lock_bh(&mfc_unres_lock);
-                cp = &net->ipv6.mfc6_unres_queue;
-                while ((c = *cp) != NULL) {
-                        *cp = c->next;
+                list_for_each_entry_safe(c, next, &net->ipv6.mfc6_unres_queue, list) {
+                        list_del(&c->list);
                         ip6mr_destroy_unres(net, c);
                 }
                 spin_unlock_bh(&mfc_unres_lock);