ipv4: ipmr: convert struct mfc_cache to struct list_head

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/mroute.h b/include/linux/mroute.h
index de7780a..7ff6c77 100644 (file)
--- a/include/linux/mroute.h
+++ b/include/linux/mroute.h
@@ -191,7 +191,7 @@ struct vif_device {
 #define VIFF_STATIC 0x8000
 
 struct mfc_cache {
-       struct mfc_cache *next;                 /* Next entry on cache line     */
+       struct list_head list;
        __be32 mfc_mcastgrp;                    /* Group the entry belongs to   */
        __be32 mfc_origin;                      /* Source of packet             */
        vifi_t mfc_parent;                      /* Source interface             */

diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h
index b15e518..5d06429 100644 (file)
--- a/include/net/netns/ipv4.h
+++ b/include/net/netns/ipv4.h
@@ -61,8 +61,8 @@ struct netns_ipv4 {
 #ifdef CONFIG_IP_MROUTE
        struct sock             *mroute_sk;
        struct timer_list       ipmr_expire_timer;
-       struct mfc_cache        *mfc_unres_queue;
-       struct mfc_cache        **mfc_cache_array;
+       struct list_head        mfc_unres_queue;
+       struct list_head        *mfc_cache_array;
        struct vif_device       *vif_table;
        int                     maxvif;
        atomic_t                cache_resolve_queue_len;

diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index f8e25c8..21b5edc 100644 (file)
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -367,35 +367,32 @@ static void ipmr_expire_process(unsigned long arg)
        struct net *net = (struct net *)arg;
        unsigned long now;
        unsigned long expires;
-       struct mfc_cache *c, **cp;
+       struct mfc_cache *c, *next;
 
        if (!spin_trylock(&mfc_unres_lock)) {
                mod_timer(&net->ipv4.ipmr_expire_timer, jiffies+HZ/10);
                return;
        }
 
-       if (net->ipv4.mfc_unres_queue == NULL)
+       if (list_empty(&net->ipv4.mfc_unres_queue))
                goto out;
 
        now = jiffies;
        expires = 10*HZ;
-       cp = &net->ipv4.mfc_unres_queue;
 
-       while ((c=*cp) != NULL) {
+       list_for_each_entry_safe(c, next, &net->ipv4.mfc_unres_queue, list) {
                if (time_after(c->mfc_un.unres.expires, now)) {
                        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);
                ipmr_destroy_unres(net, c);
        }
 
-       if (net->ipv4.mfc_unres_queue != NULL)
+       if (!list_empty(&net->ipv4.mfc_unres_queue))
                mod_timer(&net->ipv4.ipmr_expire_timer, jiffies + expires);
 
 out:
@@ -537,11 +534,11 @@ static struct mfc_cache *ipmr_cache_find(struct net *net,
        int line = MFC_HASH(mcastgrp, origin);
        struct mfc_cache *c;
 
-       for (c = net->ipv4.mfc_cache_array[line]; c; c = c->next) {
-               if (c->mfc_origin==origin && c->mfc_mcastgrp==mcastgrp)
-                       break;
+       list_for_each_entry(c, &net->ipv4.mfc_cache_array[line], list) {
+               if (c->mfc_origin == origin && c->mfc_mcastgrp == mcastgrp)
+                       return c;
        }
-       return c;
+       return NULL;
 }
 
 /*
@@ -699,18 +696,21 @@ static int ipmr_cache_report(struct net *net,
 static int
 ipmr_cache_unresolved(struct net *net, vifi_t vifi, struct sk_buff *skb)
 {
+       bool found = false;
        int err;
        struct mfc_cache *c;
        const struct iphdr *iph = ip_hdr(skb);
 
        spin_lock_bh(&mfc_unres_lock);
-       for (c=net->ipv4.mfc_unres_queue; c; c=c->next) {
+       list_for_each_entry(c, &net->ipv4.mfc_unres_queue, list) {
                if (c->mfc_mcastgrp == iph->daddr &&
-                   c->mfc_origin == iph->saddr)
+                   c->mfc_origin == iph->saddr) {
+                       found = true;
                        break;
+               }
        }
 
-       if (c == NULL) {
+       if (!found) {
                /*
                 *      Create a new entry if allowable
                 */
@@ -746,8 +746,7 @@ ipmr_cache_unresolved(struct net *net, vifi_t vifi, struct sk_buff *skb)
                }
 
                atomic_inc(&net->ipv4.cache_resolve_queue_len);
-               c->next = net->ipv4.mfc_unres_queue;
-               net->ipv4.mfc_unres_queue = c;
+               list_add(&c->list, &net->ipv4.mfc_unres_queue);
 
                mod_timer(&net->ipv4.ipmr_expire_timer, c->mfc_un.unres.expires);
        }
@@ -774,16 +773,15 @@ ipmr_cache_unresolved(struct net *net, vifi_t vifi, struct sk_buff *skb)
 static int ipmr_mfc_delete(struct net *net, struct mfcctl *mfc)
 {
        int line;
-       struct mfc_cache *c, **cp;
+       struct mfc_cache *c, *next;
 
        line = MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr);
 
-       for (cp = &net->ipv4.mfc_cache_array[line];
-            (c = *cp) != NULL; cp = &c->next) {
+       list_for_each_entry_safe(c, next, &net->ipv4.mfc_cache_array[line], list) {
                if (c->mfc_origin == mfc->mfcc_origin.s_addr &&
                    c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr) {
                        write_lock_bh(&mrt_lock);
-                       *cp = c->next;
+                       list_del(&c->list);
                        write_unlock_bh(&mrt_lock);
 
                        ipmr_cache_free(c);
@@ -795,22 +793,24 @@ static int ipmr_mfc_delete(struct net *net, struct mfcctl *mfc)
 
 static int ipmr_mfc_add(struct net *net, struct mfcctl *mfc, int mrtsock)
 {
+       bool found = false;
        int line;
-       struct mfc_cache *uc, *c, **cp;
+       struct mfc_cache *uc, *c;
 
        if (mfc->mfcc_parent >= MAXVIFS)
                return -ENFILE;
 
        line = MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr);
 
-       for (cp = &net->ipv4.mfc_cache_array[line];
-            (c = *cp) != NULL; cp = &c->next) {
+       list_for_each_entry(c, &net->ipv4.mfc_cache_array[line], list) {
                if (c->mfc_origin == mfc->mfcc_origin.s_addr &&
-                   c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr)
+                   c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr) {
+                       found = true;
                        break;
+               }
        }
 
-       if (c != NULL) {
+       if (found) {
                write_lock_bh(&mrt_lock);
                c->mfc_parent = mfc->mfcc_parent;
                ipmr_update_thresholds(net, c, mfc->mfcc_ttls);
@@ -835,8 +835,7 @@ static int ipmr_mfc_add(struct net *net, struct mfcctl *mfc, int mrtsock)
                c->mfc_flags |= MFC_STATIC;
 
        write_lock_bh(&mrt_lock);
-       c->next = net->ipv4.mfc_cache_array[line];
-       net->ipv4.mfc_cache_array[line] = c;
+       list_add(&c->list, &net->ipv4.mfc_cache_array[line]);
        write_unlock_bh(&mrt_lock);
 
        /*
@@ -844,16 +843,15 @@ static int ipmr_mfc_add(struct net *net, struct mfcctl *mfc, int mrtsock)
         *      need to send on the frames and tidy up.
         */
        spin_lock_bh(&mfc_unres_lock);
-       for (cp = &net->ipv4.mfc_unres_queue; (uc=*cp) != NULL;
-            cp = &uc->next) {
+       list_for_each_entry(uc, &net->ipv4.mfc_unres_queue, list) {
                if (uc->mfc_origin == c->mfc_origin &&
                    uc->mfc_mcastgrp == c->mfc_mcastgrp) {
-                       *cp = uc->next;
+                       list_del(&uc->list);
                        atomic_dec(&net->ipv4.cache_resolve_queue_len);
                        break;
                }
        }
-       if (net->ipv4.mfc_unres_queue == NULL)
+       if (list_empty(&net->ipv4.mfc_unres_queue))
                del_timer(&net->ipv4.ipmr_expire_timer);
        spin_unlock_bh(&mfc_unres_lock);
 
@@ -872,6 +870,7 @@ static void mroute_clean_tables(struct net *net)
 {
        int i;
        LIST_HEAD(list);
+       struct mfc_cache *c, *next;
 
        /*
         *      Shut down all active vif entries
@@ -885,17 +884,12 @@ static void mroute_clean_tables(struct net *net)
        /*
         *      Wipe the cache
         */
-       for (i=0; i<MFC_LINES; i++) {
-               struct mfc_cache *c, **cp;
-
-               cp = &net->ipv4.mfc_cache_array[i];
-               while ((c = *cp) != NULL) {
-                       if (c->mfc_flags&MFC_STATIC) {
-                               cp = &c->next;
+       for (i = 0; i < MFC_LINES; i++) {
+               list_for_each_entry_safe(c, next, &net->ipv4.mfc_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);
 
                        ipmr_cache_free(c);
@@ -903,12 +897,9 @@ static void mroute_clean_tables(struct net *net)
        }
 
        if (atomic_read(&net->ipv4.cache_resolve_queue_len) != 0) {
-               struct mfc_cache *c, **cp;
-
                spin_lock_bh(&mfc_unres_lock);
-               cp = &net->ipv4.mfc_unres_queue;
-               while ((c = *cp) != NULL) {
-                       *cp = c->next;
+               list_for_each_entry_safe(c, next, &net->ipv4.mfc_unres_queue, list) {
+                       list_del(&c->list);
                        ipmr_destroy_unres(net, c);
                }
                spin_unlock_bh(&mfc_unres_lock);
@@ -1789,7 +1780,7 @@ static const struct file_operations ipmr_vif_fops = {
 
 struct ipmr_mfc_iter {
        struct seq_net_private p;
-       struct mfc_cache **cache;
+       struct list_head *cache;
        int ct;
 };
 
@@ -1799,18 +1790,18 @@ static struct mfc_cache *ipmr_mfc_seq_idx(struct net *net,
 {
        struct mfc_cache *mfc;
 
-       it->cache = net->ipv4.mfc_cache_array;
        read_lock(&mrt_lock);
-       for (it->ct = 0; it->ct < MFC_LINES; it->ct++)
-               for (mfc = net->ipv4.mfc_cache_array[it->ct];
-                    mfc; mfc = mfc->next)
+       for (it->ct = 0; it->ct < MFC_LINES; it->ct++) {
+               it->cache = &net->ipv4.mfc_cache_array[it->ct];
+               list_for_each_entry(mfc, it->cache, list)
                        if (pos-- == 0)
                                return mfc;
+       }
        read_unlock(&mrt_lock);
 
-       it->cache = &net->ipv4.mfc_unres_queue;
        spin_lock_bh(&mfc_unres_lock);
-       for (mfc = net->ipv4.mfc_unres_queue; mfc; mfc = mfc->next)
+       it->cache = &net->ipv4.mfc_unres_queue;
+       list_for_each_entry(mfc, it->cache, list)
                if (pos-- == 0)
                        return mfc;
        spin_unlock_bh(&mfc_unres_lock);
@@ -1842,18 +1833,19 @@ 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 mfc_cache, list);
 
        if (it->cache == &net->ipv4.mfc_unres_queue)
                goto end_of_list;
 
-       BUG_ON(it->cache != net->ipv4.mfc_cache_array);
+       BUG_ON(it->cache != &net->ipv4.mfc_cache_array[it->ct]);
 
        while (++it->ct < MFC_LINES) {
-               mfc = net->ipv4.mfc_cache_array[it->ct];
-               if (mfc)
-                       return mfc;
+               it->cache = &net->ipv4.mfc_cache_array[it->ct];
+               if (list_empty(it->cache))
+                       continue;
+               return list_first_entry(it->cache, struct mfc_cache, list);
        }
 
        /* exhausted cache_array, show unresolved */
@@ -1862,9 +1854,8 @@ 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->ipv4.mfc_unres_queue;
-       if (mfc)
-               return mfc;
+       if (!list_empty(it->cache))
+               return list_first_entry(it->cache, struct mfc_cache, list);
 
  end_of_list:
        spin_unlock_bh(&mfc_unres_lock);
@@ -1880,7 +1871,7 @@ static void ipmr_mfc_seq_stop(struct seq_file *seq, void *v)
 
        if (it->cache == &net->ipv4.mfc_unres_queue)
                spin_unlock_bh(&mfc_unres_lock);
-       else if (it->cache == net->ipv4.mfc_cache_array)
+       else if (it->cache == &net->ipv4.mfc_cache_array[it->ct])
                read_unlock(&mrt_lock);
 }
 
@@ -1960,6 +1951,7 @@ static const struct net_protocol pim_protocol = {
  */
 static int __net_init ipmr_net_init(struct net *net)
 {
+       unsigned int i;
        int err = 0;
 
        net->ipv4.vif_table = kcalloc(MAXVIFS, sizeof(struct vif_device),
@@ -1971,13 +1963,18 @@ static int __net_init ipmr_net_init(struct net *net)
 
        /* Forwarding cache */
        net->ipv4.mfc_cache_array = kcalloc(MFC_LINES,
-                                           sizeof(struct mfc_cache *),
+                                           sizeof(struct list_head),
                                            GFP_KERNEL);
        if (!net->ipv4.mfc_cache_array) {
                err = -ENOMEM;
                goto fail_mfc_cache;
        }
 
+       for (i = 0; i < MFC_LINES; i++)
+               INIT_LIST_HEAD(&net->ipv4.mfc_cache_array[i]);
+
+       INIT_LIST_HEAD(&net->ipv4.mfc_unres_queue);
+
        setup_timer(&net->ipv4.ipmr_expire_timer, ipmr_expire_process,
                    (unsigned long)net);