#include <linux/seq_file.h>
#include <linux/nsproxy.h>
#include <linux/slab.h>
+#include <linux/jhash.h>
#include <net/net_namespace.h>
#include <net/snmp.h>
#include <net/ipv6.h>
struct in6_addr *dst, struct in6_addr *src,
int iif, int type, u32 portid, u32 seq,
unsigned int flags);
+static struct rt6_info *rt6_find_cached_rt(struct rt6_info *rt,
+ struct in6_addr *daddr,
+ struct in6_addr *saddr);
#ifdef CONFIG_IPV6_ROUTE_INFO
static struct rt6_info *rt6_add_route_info(struct net *net,
{
if (!list_empty(&rt->rt6i_uncached)) {
struct uncached_list *ul = rt->rt6i_uncached_list;
+ struct net *net = dev_net(rt->dst.dev);
spin_lock_bh(&ul->lock);
list_del(&rt->rt6i_uncached);
+ atomic_dec(&net->ipv6.rt6_stats->fib_rt_uncache);
spin_unlock_bh(&ul->lock);
}
}
struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
1, DST_OBSOLETE_FORCE_CHK, flags);
- if (rt)
+ if (rt) {
rt6_info_init(rt);
+ atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);
+ }
return rt;
}
if (rt) {
rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC);
- if (rt->rt6i_pcpu) {
- int cpu;
-
- for_each_possible_cpu(cpu) {
- struct rt6_info **p;
-
- p = per_cpu_ptr(rt->rt6i_pcpu, cpu);
- /* no one shares rt */
- *p = NULL;
- }
- } else {
+ if (!rt->rt6i_pcpu) {
dst_release_immediate(&rt->dst);
return NULL;
}
static void ip6_dst_destroy(struct dst_entry *dst)
{
struct rt6_info *rt = (struct rt6_info *)dst;
+ struct rt6_exception_bucket *bucket;
struct dst_entry *from = dst->from;
struct inet6_dev *idev;
rt->rt6i_idev = NULL;
in6_dev_put(idev);
}
+ bucket = rcu_dereference_protected(rt->rt6i_exception_bucket, 1);
+ if (bucket) {
+ rt->rt6i_exception_bucket = NULL;
+ kfree(bucket);
+ }
dst->from = NULL;
dst_release(from);
}
/*
- * Route lookup. Any table->tb6_lock is implied.
+ * Route lookup. rcu_read_lock() should be held.
*/
static inline struct rt6_info *rt6_device_match(struct net *net,
if (!oif && ipv6_addr_any(saddr))
goto out;
- for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
+ for (sprt = rt; sprt; sprt = rcu_dereference(sprt->dst.rt6_next)) {
struct net_device *dev = sprt->dst.dev;
if (oif) {
}
static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
+ struct rt6_info *leaf,
struct rt6_info *rr_head,
u32 metric, int oif, int strict,
bool *do_rr)
match = NULL;
cont = NULL;
- for (rt = rr_head; rt; rt = rt->dst.rt6_next) {
+ for (rt = rr_head; rt; rt = rcu_dereference(rt->dst.rt6_next)) {
if (rt->rt6i_metric != metric) {
cont = rt;
break;
match = find_match(rt, oif, strict, &mpri, match, do_rr);
}
- for (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) {
+ for (rt = leaf; rt && rt != rr_head;
+ rt = rcu_dereference(rt->dst.rt6_next)) {
if (rt->rt6i_metric != metric) {
cont = rt;
break;
if (match || !cont)
return match;
- for (rt = cont; rt; rt = rt->dst.rt6_next)
+ for (rt = cont; rt; rt = rcu_dereference(rt->dst.rt6_next))
match = find_match(rt, oif, strict, &mpri, match, do_rr);
return match;
}
-static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
+static struct rt6_info *rt6_select(struct net *net, struct fib6_node *fn,
+ int oif, int strict)
{
+ struct rt6_info *leaf = rcu_dereference(fn->leaf);
struct rt6_info *match, *rt0;
- struct net *net;
bool do_rr = false;
+ int key_plen;
- rt0 = fn->rr_ptr;
+ if (!leaf || leaf == net->ipv6.ip6_null_entry)
+ return net->ipv6.ip6_null_entry;
+
+ rt0 = rcu_dereference(fn->rr_ptr);
if (!rt0)
- fn->rr_ptr = rt0 = fn->leaf;
+ rt0 = leaf;
- match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict,
+ /* Double check to make sure fn is not an intermediate node
+ * and fn->leaf does not points to its child's leaf
+ * (This might happen if all routes under fn are deleted from
+ * the tree and fib6_repair_tree() is called on the node.)
+ */
+ key_plen = rt0->rt6i_dst.plen;
+#ifdef CONFIG_IPV6_SUBTREES
+ if (rt0->rt6i_src.plen)
+ key_plen = rt0->rt6i_src.plen;
+#endif
+ if (fn->fn_bit != key_plen)
+ return net->ipv6.ip6_null_entry;
+
+ match = find_rr_leaf(fn, leaf, rt0, rt0->rt6i_metric, oif, strict,
&do_rr);
if (do_rr) {
- struct rt6_info *next = rt0->dst.rt6_next;
+ struct rt6_info *next = rcu_dereference(rt0->dst.rt6_next);
/* no entries matched; do round-robin */
if (!next || next->rt6i_metric != rt0->rt6i_metric)
- next = fn->leaf;
-
- if (next != rt0)
- fn->rr_ptr = next;
+ next = leaf;
+
+ if (next != rt0) {
+ spin_lock_bh(&leaf->rt6i_table->tb6_lock);
+ /* make sure next is not being deleted from the tree */
+ if (next->rt6i_node)
+ rcu_assign_pointer(fn->rr_ptr, next);
+ spin_unlock_bh(&leaf->rt6i_table->tb6_lock);
+ }
}
- net = dev_net(rt0->dst.dev);
return match ? match : net->ipv6.ip6_null_entry;
}
static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
struct in6_addr *saddr)
{
- struct fib6_node *pn;
+ struct fib6_node *pn, *sn;
while (1) {
if (fn->fn_flags & RTN_TL_ROOT)
return NULL;
- pn = fn->parent;
- if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn)
- fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr);
+ pn = rcu_dereference(fn->parent);
+ sn = FIB6_SUBTREE(pn);
+ if (sn && sn != fn)
+ fn = fib6_lookup(sn, NULL, saddr);
else
fn = pn;
if (fn->fn_flags & RTN_RTINFO)
}
}
+static bool ip6_hold_safe(struct net *net, struct rt6_info **prt,
+ bool null_fallback)
+{
+ struct rt6_info *rt = *prt;
+
+ if (dst_hold_safe(&rt->dst))
+ return true;
+ if (null_fallback) {
+ rt = net->ipv6.ip6_null_entry;
+ dst_hold(&rt->dst);
+ } else {
+ rt = NULL;
+ }
+ *prt = rt;
+ return false;
+}
+
static struct rt6_info *ip6_pol_route_lookup(struct net *net,
struct fib6_table *table,
struct flowi6 *fl6, int flags)
{
+ struct rt6_info *rt, *rt_cache;
struct fib6_node *fn;
- struct rt6_info *rt;
- read_lock_bh(&table->tb6_lock);
+ rcu_read_lock();
fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
restart:
- rt = fn->leaf;
- rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
- if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
- rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
+ rt = rcu_dereference(fn->leaf);
+ if (!rt) {
+ rt = net->ipv6.ip6_null_entry;
+ } else {
+ rt = rt6_device_match(net, rt, &fl6->saddr,
+ fl6->flowi6_oif, flags);
+ if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
+ rt = rt6_multipath_select(rt, fl6,
+ fl6->flowi6_oif, flags);
+ }
if (rt == net->ipv6.ip6_null_entry) {
fn = fib6_backtrack(fn, &fl6->saddr);
if (fn)
goto restart;
}
- dst_use(&rt->dst, jiffies);
- read_unlock_bh(&table->tb6_lock);
+ /* Search through exception table */
+ rt_cache = rt6_find_cached_rt(rt, &fl6->daddr, &fl6->saddr);
+ if (rt_cache)
+ rt = rt_cache;
+
+ if (ip6_hold_safe(net, &rt, true))
+ dst_use_noref(&rt->dst, jiffies);
+
+ rcu_read_unlock();
- trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
+ trace_fib6_table_lookup(net, rt, table, fl6);
return rt;
struct fib6_table *table;
table = rt->rt6i_table;
- write_lock_bh(&table->tb6_lock);
+ spin_lock_bh(&table->tb6_lock);
err = fib6_add(&table->tb6_root, rt, info, mxc, extack);
- write_unlock_bh(&table->tb6_lock);
+ spin_unlock_bh(&table->tb6_lock);
return err;
}
return pcpu_rt;
}
-/* It should be called with read_lock_bh(&tb6_lock) acquired */
+/* It should be called with rcu_read_lock() acquired */
static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
{
struct rt6_info *pcpu_rt, **p;
p = this_cpu_ptr(rt->rt6i_pcpu);
pcpu_rt = *p;
- if (pcpu_rt) {
- dst_hold(&pcpu_rt->dst);
+ if (pcpu_rt && ip6_hold_safe(NULL, &pcpu_rt, false))
rt6_dst_from_metrics_check(pcpu_rt);
- }
+
return pcpu_rt;
}
static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
{
- struct fib6_table *table = rt->rt6i_table;
struct rt6_info *pcpu_rt, *prev, **p;
pcpu_rt = ip6_rt_pcpu_alloc(rt);
return net->ipv6.ip6_null_entry;
}
- read_lock_bh(&table->tb6_lock);
- if (rt->rt6i_pcpu) {
- p = this_cpu_ptr(rt->rt6i_pcpu);
- prev = cmpxchg(p, NULL, pcpu_rt);
- if (prev) {
- /* If someone did it before us, return prev instead */
- dst_release_immediate(&pcpu_rt->dst);
- pcpu_rt = prev;
- }
- } else {
- /* rt has been removed from the fib6 tree
- * before we have a chance to acquire the read_lock.
- * In this case, don't brother to create a pcpu rt
- * since rt is going away anyway. The next
- * dst_check() will trigger a re-lookup.
- */
- dst_release_immediate(&pcpu_rt->dst);
- pcpu_rt = rt;
- }
dst_hold(&pcpu_rt->dst);
+ p = this_cpu_ptr(rt->rt6i_pcpu);
+ prev = cmpxchg(p, NULL, pcpu_rt);
+ BUG_ON(prev);
+
rt6_dst_from_metrics_check(pcpu_rt);
- read_unlock_bh(&table->tb6_lock);
return pcpu_rt;
}
+/* exception hash table implementation
+ */
+static DEFINE_SPINLOCK(rt6_exception_lock);
+
+/* Remove rt6_ex from hash table and free the memory
+ * Caller must hold rt6_exception_lock
+ */
+static void rt6_remove_exception(struct rt6_exception_bucket *bucket,
+ struct rt6_exception *rt6_ex)
+{
+ struct net *net;
+
+ if (!bucket || !rt6_ex)
+ return;
+
+ net = dev_net(rt6_ex->rt6i->dst.dev);
+ rt6_ex->rt6i->rt6i_node = NULL;
+ hlist_del_rcu(&rt6_ex->hlist);
+ rt6_release(rt6_ex->rt6i);
+ kfree_rcu(rt6_ex, rcu);
+ WARN_ON_ONCE(!bucket->depth);
+ bucket->depth--;
+ net->ipv6.rt6_stats->fib_rt_cache--;
+}
+
+/* Remove oldest rt6_ex in bucket and free the memory
+ * Caller must hold rt6_exception_lock
+ */
+static void rt6_exception_remove_oldest(struct rt6_exception_bucket *bucket)
+{
+ struct rt6_exception *rt6_ex, *oldest = NULL;
+
+ if (!bucket)
+ return;
+
+ hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
+ if (!oldest || time_before(rt6_ex->stamp, oldest->stamp))
+ oldest = rt6_ex;
+ }
+ rt6_remove_exception(bucket, oldest);
+}
+
+static u32 rt6_exception_hash(const struct in6_addr *dst,
+ const struct in6_addr *src)
+{
+ static u32 seed __read_mostly;
+ u32 val;
+
+ net_get_random_once(&seed, sizeof(seed));
+ val = jhash(dst, sizeof(*dst), seed);
+
+#ifdef CONFIG_IPV6_SUBTREES
+ if (src)
+ val = jhash(src, sizeof(*src), val);
+#endif
+ return hash_32(val, FIB6_EXCEPTION_BUCKET_SIZE_SHIFT);
+}
+
+/* Helper function to find the cached rt in the hash table
+ * and update bucket pointer to point to the bucket for this
+ * (daddr, saddr) pair
+ * Caller must hold rt6_exception_lock
+ */
+static struct rt6_exception *
+__rt6_find_exception_spinlock(struct rt6_exception_bucket **bucket,
+ const struct in6_addr *daddr,
+ const struct in6_addr *saddr)
+{
+ struct rt6_exception *rt6_ex;
+ u32 hval;
+
+ if (!(*bucket) || !daddr)
+ return NULL;
+
+ hval = rt6_exception_hash(daddr, saddr);
+ *bucket += hval;
+
+ hlist_for_each_entry(rt6_ex, &(*bucket)->chain, hlist) {
+ struct rt6_info *rt6 = rt6_ex->rt6i;
+ bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr);
+
+#ifdef CONFIG_IPV6_SUBTREES
+ if (matched && saddr)
+ matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr);
+#endif
+ if (matched)
+ return rt6_ex;
+ }
+ return NULL;
+}
+
+/* Helper function to find the cached rt in the hash table
+ * and update bucket pointer to point to the bucket for this
+ * (daddr, saddr) pair
+ * Caller must hold rcu_read_lock()
+ */
+static struct rt6_exception *
+__rt6_find_exception_rcu(struct rt6_exception_bucket **bucket,
+ const struct in6_addr *daddr,
+ const struct in6_addr *saddr)
+{
+ struct rt6_exception *rt6_ex;
+ u32 hval;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ if (!(*bucket) || !daddr)
+ return NULL;
+
+ hval = rt6_exception_hash(daddr, saddr);
+ *bucket += hval;
+
+ hlist_for_each_entry_rcu(rt6_ex, &(*bucket)->chain, hlist) {
+ struct rt6_info *rt6 = rt6_ex->rt6i;
+ bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr);
+
+#ifdef CONFIG_IPV6_SUBTREES
+ if (matched && saddr)
+ matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr);
+#endif
+ if (matched)
+ return rt6_ex;
+ }
+ return NULL;
+}
+
+static int rt6_insert_exception(struct rt6_info *nrt,
+ struct rt6_info *ort)
+{
+ struct net *net = dev_net(ort->dst.dev);
+ struct rt6_exception_bucket *bucket;
+ struct in6_addr *src_key = NULL;
+ struct rt6_exception *rt6_ex;
+ int err = 0;
+
+ /* ort can't be a cache or pcpu route */
+ if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
+ ort = (struct rt6_info *)ort->dst.from;
+ WARN_ON_ONCE(ort->rt6i_flags & (RTF_CACHE | RTF_PCPU));
+
+ spin_lock_bh(&rt6_exception_lock);
+
+ if (ort->exception_bucket_flushed) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ bucket = rcu_dereference_protected(ort->rt6i_exception_bucket,
+ lockdep_is_held(&rt6_exception_lock));
+ if (!bucket) {
+ bucket = kcalloc(FIB6_EXCEPTION_BUCKET_SIZE, sizeof(*bucket),
+ GFP_ATOMIC);
+ if (!bucket) {
+ err = -ENOMEM;
+ goto out;
+ }
+ rcu_assign_pointer(ort->rt6i_exception_bucket, bucket);
+ }
+
+#ifdef CONFIG_IPV6_SUBTREES
+ /* rt6i_src.plen != 0 indicates ort is in subtree
+ * and exception table is indexed by a hash of
+ * both rt6i_dst and rt6i_src.
+ * Otherwise, the exception table is indexed by
+ * a hash of only rt6i_dst.
+ */
+ if (ort->rt6i_src.plen)
+ src_key = &nrt->rt6i_src.addr;
+#endif
+
+ /* Update rt6i_prefsrc as it could be changed
+ * in rt6_remove_prefsrc()
+ */
+ nrt->rt6i_prefsrc = ort->rt6i_prefsrc;
+ /* rt6_mtu_change() might lower mtu on ort.
+ * Only insert this exception route if its mtu
+ * is less than ort's mtu value.
+ */
+ if (nrt->rt6i_pmtu >= dst_mtu(&ort->dst)) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ rt6_ex = __rt6_find_exception_spinlock(&bucket, &nrt->rt6i_dst.addr,
+ src_key);
+ if (rt6_ex)
+ rt6_remove_exception(bucket, rt6_ex);
+
+ rt6_ex = kzalloc(sizeof(*rt6_ex), GFP_ATOMIC);
+ if (!rt6_ex) {
+ err = -ENOMEM;
+ goto out;
+ }
+ rt6_ex->rt6i = nrt;
+ rt6_ex->stamp = jiffies;
+ atomic_inc(&nrt->rt6i_ref);
+ nrt->rt6i_node = ort->rt6i_node;
+ hlist_add_head_rcu(&rt6_ex->hlist, &bucket->chain);
+ bucket->depth++;
+ net->ipv6.rt6_stats->fib_rt_cache++;
+
+ if (bucket->depth > FIB6_MAX_DEPTH)
+ rt6_exception_remove_oldest(bucket);
+
+out:
+ spin_unlock_bh(&rt6_exception_lock);
+
+ /* Update fn->fn_sernum to invalidate all cached dst */
+ if (!err) {
+ fib6_update_sernum(ort);
+ fib6_force_start_gc(net);
+ }
+
+ return err;
+}
+
+void rt6_flush_exceptions(struct rt6_info *rt)
+{
+ struct rt6_exception_bucket *bucket;
+ struct rt6_exception *rt6_ex;
+ struct hlist_node *tmp;
+ int i;
+
+ spin_lock_bh(&rt6_exception_lock);
+ /* Prevent rt6_insert_exception() to recreate the bucket list */
+ rt->exception_bucket_flushed = 1;
+
+ bucket = rcu_dereference_protected(rt->rt6i_exception_bucket,
+ lockdep_is_held(&rt6_exception_lock));
+ if (!bucket)
+ goto out;
+
+ for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
+ hlist_for_each_entry_safe(rt6_ex, tmp, &bucket->chain, hlist)
+ rt6_remove_exception(bucket, rt6_ex);
+ WARN_ON_ONCE(bucket->depth);
+ bucket++;
+ }
+
+out:
+ spin_unlock_bh(&rt6_exception_lock);
+}
+
+/* Find cached rt in the hash table inside passed in rt
+ * Caller has to hold rcu_read_lock()
+ */
+static struct rt6_info *rt6_find_cached_rt(struct rt6_info *rt,
+ struct in6_addr *daddr,
+ struct in6_addr *saddr)
+{
+ struct rt6_exception_bucket *bucket;
+ struct in6_addr *src_key = NULL;
+ struct rt6_exception *rt6_ex;
+ struct rt6_info *res = NULL;
+
+ bucket = rcu_dereference(rt->rt6i_exception_bucket);
+
+#ifdef CONFIG_IPV6_SUBTREES
+ /* rt6i_src.plen != 0 indicates rt is in subtree
+ * and exception table is indexed by a hash of
+ * both rt6i_dst and rt6i_src.
+ * Otherwise, the exception table is indexed by
+ * a hash of only rt6i_dst.
+ */
+ if (rt->rt6i_src.plen)
+ src_key = saddr;
+#endif
+ rt6_ex = __rt6_find_exception_rcu(&bucket, daddr, src_key);
+
+ if (rt6_ex && !rt6_check_expired(rt6_ex->rt6i))
+ res = rt6_ex->rt6i;
+
+ return res;
+}
+
+/* Remove the passed in cached rt from the hash table that contains it */
+int rt6_remove_exception_rt(struct rt6_info *rt)
+{
+ struct rt6_info *from = (struct rt6_info *)rt->dst.from;
+ struct rt6_exception_bucket *bucket;
+ struct in6_addr *src_key = NULL;
+ struct rt6_exception *rt6_ex;
+ int err;
+
+ if (!from ||
+ !(rt->rt6i_flags & RTF_CACHE))
+ return -EINVAL;
+
+ if (!rcu_access_pointer(from->rt6i_exception_bucket))
+ return -ENOENT;
+
+ spin_lock_bh(&rt6_exception_lock);
+ bucket = rcu_dereference_protected(from->rt6i_exception_bucket,
+ lockdep_is_held(&rt6_exception_lock));
+#ifdef CONFIG_IPV6_SUBTREES
+ /* rt6i_src.plen != 0 indicates 'from' is in subtree
+ * and exception table is indexed by a hash of
+ * both rt6i_dst and rt6i_src.
+ * Otherwise, the exception table is indexed by
+ * a hash of only rt6i_dst.
+ */
+ if (from->rt6i_src.plen)
+ src_key = &rt->rt6i_src.addr;
+#endif
+ rt6_ex = __rt6_find_exception_spinlock(&bucket,
+ &rt->rt6i_dst.addr,
+ src_key);
+ if (rt6_ex) {
+ rt6_remove_exception(bucket, rt6_ex);
+ err = 0;
+ } else {
+ err = -ENOENT;
+ }
+
+ spin_unlock_bh(&rt6_exception_lock);
+ return err;
+}
+
+/* Find rt6_ex which contains the passed in rt cache and
+ * refresh its stamp
+ */
+static void rt6_update_exception_stamp_rt(struct rt6_info *rt)
+{
+ struct rt6_info *from = (struct rt6_info *)rt->dst.from;
+ struct rt6_exception_bucket *bucket;
+ struct in6_addr *src_key = NULL;
+ struct rt6_exception *rt6_ex;
+
+ if (!from ||
+ !(rt->rt6i_flags & RTF_CACHE))
+ return;
+
+ rcu_read_lock();
+ bucket = rcu_dereference(from->rt6i_exception_bucket);
+
+#ifdef CONFIG_IPV6_SUBTREES
+ /* rt6i_src.plen != 0 indicates 'from' is in subtree
+ * and exception table is indexed by a hash of
+ * both rt6i_dst and rt6i_src.
+ * Otherwise, the exception table is indexed by
+ * a hash of only rt6i_dst.
+ */
+ if (from->rt6i_src.plen)
+ src_key = &rt->rt6i_src.addr;
+#endif
+ rt6_ex = __rt6_find_exception_rcu(&bucket,
+ &rt->rt6i_dst.addr,
+ src_key);
+ if (rt6_ex)
+ rt6_ex->stamp = jiffies;
+
+ rcu_read_unlock();
+}
+
+static void rt6_exceptions_remove_prefsrc(struct rt6_info *rt)
+{
+ struct rt6_exception_bucket *bucket;
+ struct rt6_exception *rt6_ex;
+ int i;
+
+ bucket = rcu_dereference_protected(rt->rt6i_exception_bucket,
+ lockdep_is_held(&rt6_exception_lock));
+
+ if (bucket) {
+ for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
+ hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
+ rt6_ex->rt6i->rt6i_prefsrc.plen = 0;
+ }
+ bucket++;
+ }
+ }
+}
+
+static void rt6_exceptions_update_pmtu(struct rt6_info *rt, int mtu)
+{
+ struct rt6_exception_bucket *bucket;
+ struct rt6_exception *rt6_ex;
+ int i;
+
+ bucket = rcu_dereference_protected(rt->rt6i_exception_bucket,
+ lockdep_is_held(&rt6_exception_lock));
+
+ if (bucket) {
+ for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
+ hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
+ struct rt6_info *entry = rt6_ex->rt6i;
+ /* For RTF_CACHE with rt6i_pmtu == 0
+ * (i.e. a redirected route),
+ * the metrics of its rt->dst.from has already
+ * been updated.
+ */
+ if (entry->rt6i_pmtu && entry->rt6i_pmtu > mtu)
+ entry->rt6i_pmtu = mtu;
+ }
+ bucket++;
+ }
+ }
+}
+
+#define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE)
+
+static void rt6_exceptions_clean_tohost(struct rt6_info *rt,
+ struct in6_addr *gateway)
+{
+ struct rt6_exception_bucket *bucket;
+ struct rt6_exception *rt6_ex;
+ struct hlist_node *tmp;
+ int i;
+
+ if (!rcu_access_pointer(rt->rt6i_exception_bucket))
+ return;
+
+ spin_lock_bh(&rt6_exception_lock);
+ bucket = rcu_dereference_protected(rt->rt6i_exception_bucket,
+ lockdep_is_held(&rt6_exception_lock));
+
+ if (bucket) {
+ for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
+ hlist_for_each_entry_safe(rt6_ex, tmp,
+ &bucket->chain, hlist) {
+ struct rt6_info *entry = rt6_ex->rt6i;
+
+ if ((entry->rt6i_flags & RTF_CACHE_GATEWAY) ==
+ RTF_CACHE_GATEWAY &&
+ ipv6_addr_equal(gateway,
+ &entry->rt6i_gateway)) {
+ rt6_remove_exception(bucket, rt6_ex);
+ }
+ }
+ bucket++;
+ }
+ }
+
+ spin_unlock_bh(&rt6_exception_lock);
+}
+
+static void rt6_age_examine_exception(struct rt6_exception_bucket *bucket,
+ struct rt6_exception *rt6_ex,
+ struct fib6_gc_args *gc_args,
+ unsigned long now)
+{
+ struct rt6_info *rt = rt6_ex->rt6i;
+
+ /* we are pruning and obsoleting aged-out and non gateway exceptions
+ * even if others have still references to them, so that on next
+ * dst_check() such references can be dropped.
+ * EXPIRES exceptions - e.g. pmtu-generated ones are pruned when
+ * expired, independently from their aging, as per RFC 8201 section 4
+ */
+ if (!(rt->rt6i_flags & RTF_EXPIRES) &&
+ time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) {
+ RT6_TRACE("aging clone %p\n", rt);
+ rt6_remove_exception(bucket, rt6_ex);
+ return;
+ } else if (rt->rt6i_flags & RTF_GATEWAY) {
+ struct neighbour *neigh;
+ __u8 neigh_flags = 0;
+
+ neigh = dst_neigh_lookup(&rt->dst, &rt->rt6i_gateway);
+ if (neigh) {
+ neigh_flags = neigh->flags;
+ neigh_release(neigh);
+ }
+ if (!(neigh_flags & NTF_ROUTER)) {
+ RT6_TRACE("purging route %p via non-router but gateway\n",
+ rt);
+ rt6_remove_exception(bucket, rt6_ex);
+ return;
+ }
+ } else if (__rt6_check_expired(rt)) {
+ RT6_TRACE("purging expired route %p\n", rt);
+ rt6_remove_exception(bucket, rt6_ex);
+ return;
+ }
+ gc_args->more++;
+}
+
+void rt6_age_exceptions(struct rt6_info *rt,
+ struct fib6_gc_args *gc_args,
+ unsigned long now)
+{
+ struct rt6_exception_bucket *bucket;
+ struct rt6_exception *rt6_ex;
+ struct hlist_node *tmp;
+ int i;
+
+ if (!rcu_access_pointer(rt->rt6i_exception_bucket))
+ return;
+
+ spin_lock_bh(&rt6_exception_lock);
+ bucket = rcu_dereference_protected(rt->rt6i_exception_bucket,
+ lockdep_is_held(&rt6_exception_lock));
+
+ if (bucket) {
+ for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
+ hlist_for_each_entry_safe(rt6_ex, tmp,
+ &bucket->chain, hlist) {
+ rt6_age_examine_exception(bucket, rt6_ex,
+ gc_args, now);
+ }
+ bucket++;
+ }
+ }
+ spin_unlock_bh(&rt6_exception_lock);
+}
+
struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
int oif, struct flowi6 *fl6, int flags)
{
struct fib6_node *fn, *saved_fn;
- struct rt6_info *rt;
+ struct rt6_info *rt, *rt_cache;
int strict = 0;
strict |= flags & RT6_LOOKUP_F_IFACE;
if (net->ipv6.devconf_all->forwarding == 0)
strict |= RT6_LOOKUP_F_REACHABLE;
- read_lock_bh(&table->tb6_lock);
+ rcu_read_lock();
fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
saved_fn = fn;
oif = 0;
redo_rt6_select:
- rt = rt6_select(fn, oif, strict);
+ rt = rt6_select(net, fn, oif, strict);
if (rt->rt6i_nsiblings)
rt = rt6_multipath_select(rt, fl6, oif, strict);
if (rt == net->ipv6.ip6_null_entry) {
}
}
+ /*Search through exception table */
+ rt_cache = rt6_find_cached_rt(rt, &fl6->daddr, &fl6->saddr);
+ if (rt_cache)
+ rt = rt_cache;
- if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) {
- dst_use(&rt->dst, jiffies);
- read_unlock_bh(&table->tb6_lock);
-
- rt6_dst_from_metrics_check(rt);
-
- trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
+ if (rt == net->ipv6.ip6_null_entry) {
+ rcu_read_unlock();
+ dst_hold(&rt->dst);
+ trace_fib6_table_lookup(net, rt, table, fl6);
+ return rt;
+ } else if (rt->rt6i_flags & RTF_CACHE) {
+ if (ip6_hold_safe(net, &rt, true)) {
+ dst_use_noref(&rt->dst, jiffies);
+ rt6_dst_from_metrics_check(rt);
+ }
+ rcu_read_unlock();
+ trace_fib6_table_lookup(net, rt, table, fl6);
return rt;
} else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
!(rt->rt6i_flags & RTF_GATEWAY))) {
struct rt6_info *uncached_rt;
- dst_use(&rt->dst, jiffies);
- read_unlock_bh(&table->tb6_lock);
+ if (ip6_hold_safe(net, &rt, true)) {
+ dst_use_noref(&rt->dst, jiffies);
+ } else {
+ rcu_read_unlock();
+ uncached_rt = rt;
+ goto uncached_rt_out;
+ }
+ rcu_read_unlock();
uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL);
dst_release(&rt->dst);
* No need for another dst_hold()
*/
rt6_uncached_list_add(uncached_rt);
+ atomic_inc(&net->ipv6.rt6_stats->fib_rt_uncache);
} else {
uncached_rt = net->ipv6.ip6_null_entry;
dst_hold(&uncached_rt->dst);
}
- trace_fib6_table_lookup(net, uncached_rt, table->tb6_id, fl6);
+uncached_rt_out:
+ trace_fib6_table_lookup(net, uncached_rt, table, fl6);
return uncached_rt;
} else {
struct rt6_info *pcpu_rt;
- rt->dst.lastuse = jiffies;
- rt->dst.__use++;
+ dst_use_noref(&rt->dst, jiffies);
+ local_bh_disable();
pcpu_rt = rt6_get_pcpu_route(rt);
- if (pcpu_rt) {
- read_unlock_bh(&table->tb6_lock);
- } else {
- /* We have to do the read_unlock first
- * because rt6_make_pcpu_route() may trigger
- * ip6_dst_gc() which will take the write_lock.
- */
- dst_hold(&rt->dst);
- read_unlock_bh(&table->tb6_lock);
- pcpu_rt = rt6_make_pcpu_route(rt);
- dst_release(&rt->dst);
+ if (!pcpu_rt) {
+ /* atomic_inc_not_zero() is needed when using rcu */
+ if (atomic_inc_not_zero(&rt->rt6i_ref)) {
+ /* No dst_hold() on rt is needed because grabbing
+ * rt->rt6i_ref makes sure rt can't be released.
+ */
+ pcpu_rt = rt6_make_pcpu_route(rt);
+ rt6_release(rt);
+ } else {
+ /* rt is already removed from tree */
+ pcpu_rt = net->ipv6.ip6_null_entry;
+ dst_hold(&pcpu_rt->dst);
+ }
}
-
- trace_fib6_table_lookup(net, pcpu_rt, table->tb6_id, fl6);
+ local_bh_enable();
+ rcu_read_unlock();
+ trace_fib6_table_lookup(net, pcpu_rt, table, fl6);
return pcpu_rt;
-
}
}
EXPORT_SYMBOL_GPL(ip6_pol_route);
DST_OBSOLETE_DEAD, 0);
if (rt) {
rt6_info_init(rt);
+ atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);
new = &rt->dst;
new->__use = 1;
if (!rt6_cache_allowed_for_pmtu(rt6)) {
rt6_do_update_pmtu(rt6, mtu);
+ /* update rt6_ex->stamp for cache */
+ if (rt6->rt6i_flags & RTF_CACHE)
+ rt6_update_exception_stamp_rt(rt6);
} else if (daddr) {
struct rt6_info *nrt6;
nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
if (nrt6) {
rt6_do_update_pmtu(nrt6, mtu);
-
- /* ip6_ins_rt(nrt6) will bump the
- * rt6->rt6i_node->fn_sernum
- * which will fail the next rt6_check() and
- * invalidate the sk->sk_dst_cache.
- */
- ip6_ins_rt(nrt6);
- /* Release the reference taken in
- * ip6_rt_cache_alloc()
- */
- dst_release(&nrt6->dst);
+ if (rt6_insert_exception(nrt6, rt6))
+ dst_release_immediate(&nrt6->dst);
}
}
}
int flags)
{
struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
- struct rt6_info *rt;
+ struct rt6_info *rt, *rt_cache;
struct fib6_node *fn;
/* Get the "current" route for this destination and
* routes.
*/
- read_lock_bh(&table->tb6_lock);
+ rcu_read_lock();
fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
restart:
- for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
+ for_each_fib6_node_rt_rcu(fn) {
if (rt6_check_expired(rt))
continue;
if (rt->dst.error)
continue;
if (fl6->flowi6_oif != rt->dst.dev->ifindex)
continue;
- if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
+ /* rt_cache's gateway might be different from its 'parent'
+ * in the case of an ip redirect.
+ * So we keep searching in the exception table if the gateway
+ * is different.
+ */
+ if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway)) {
+ rt_cache = rt6_find_cached_rt(rt,
+ &fl6->daddr,
+ &fl6->saddr);
+ if (rt_cache &&
+ ipv6_addr_equal(&rdfl->gateway,
+ &rt_cache->rt6i_gateway)) {
+ rt = rt_cache;
+ break;
+ }
continue;
+ }
break;
}
}
out:
- dst_hold(&rt->dst);
+ ip6_hold_safe(net, &rt, true);
- read_unlock_bh(&table->tb6_lock);
+ rcu_read_unlock();
- trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
+ trace_fib6_table_lookup(net, rt, table, fl6);
return rt;
};
* do proper release of the net_device
*/
rt6_uncached_list_add(rt);
+ atomic_inc(&net->ipv6.rt6_stats->fib_rt_uncache);
dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
static int ip6_convert_metrics(struct mx6_config *mxc,
const struct fib6_config *cfg)
{
+ struct net *net = cfg->fc_nlinfo.nl_net;
bool ecn_ca = false;
struct nlattr *nla;
int remaining;
char tmp[TCP_CA_NAME_MAX];
nla_strlcpy(tmp, nla, sizeof(tmp));
- val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
+ val = tcp_ca_get_key_by_name(net, tmp, &ecn_ca);
if (val == TCP_CA_UNSPEC)
goto err;
} else {
goto out;
}
+ /* RTF_CACHE is an internal flag; can not be set by userspace */
+ if (cfg->fc_flags & RTF_CACHE) {
+ NL_SET_ERR_MSG(extack, "Userspace can not set RTF_CACHE");
+ goto out;
+ }
+
if (cfg->fc_dst_len > 128) {
NL_SET_ERR_MSG(extack, "Invalid prefix length");
goto out;
}
table = rt->rt6i_table;
- write_lock_bh(&table->tb6_lock);
+ spin_lock_bh(&table->tb6_lock);
err = fib6_del(rt, info);
- write_unlock_bh(&table->tb6_lock);
+ spin_unlock_bh(&table->tb6_lock);
out:
ip6_rt_put(rt);
if (rt == net->ipv6.ip6_null_entry)
goto out_put;
table = rt->rt6i_table;
- write_lock_bh(&table->tb6_lock);
+ spin_lock_bh(&table->tb6_lock);
if (rt->rt6i_nsiblings && cfg->fc_delete_all_nh) {
struct rt6_info *sibling, *next_sibling;
err = fib6_del(rt, info);
out_unlock:
- write_unlock_bh(&table->tb6_lock);
+ spin_unlock_bh(&table->tb6_lock);
out_put:
ip6_rt_put(rt);
static int ip6_route_del(struct fib6_config *cfg,
struct netlink_ext_ack *extack)
{
+ struct rt6_info *rt, *rt_cache;
struct fib6_table *table;
struct fib6_node *fn;
- struct rt6_info *rt;
int err = -ESRCH;
table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
return err;
}
- read_lock_bh(&table->tb6_lock);
+ rcu_read_lock();
fn = fib6_locate(&table->tb6_root,
&cfg->fc_dst, cfg->fc_dst_len,
- &cfg->fc_src, cfg->fc_src_len);
+ &cfg->fc_src, cfg->fc_src_len,
+ !(cfg->fc_flags & RTF_CACHE));
if (fn) {
- for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
- if ((rt->rt6i_flags & RTF_CACHE) &&
- !(cfg->fc_flags & RTF_CACHE))
- continue;
+ for_each_fib6_node_rt_rcu(fn) {
+ if (cfg->fc_flags & RTF_CACHE) {
+ rt_cache = rt6_find_cached_rt(rt, &cfg->fc_dst,
+ &cfg->fc_src);
+ if (!rt_cache)
+ continue;
+ rt = rt_cache;
+ }
if (cfg->fc_ifindex &&
(!rt->dst.dev ||
rt->dst.dev->ifindex != cfg->fc_ifindex))
continue;
if (cfg->fc_protocol && cfg->fc_protocol != rt->rt6i_protocol)
continue;
- dst_hold(&rt->dst);
- read_unlock_bh(&table->tb6_lock);
+ if (!dst_hold_safe(&rt->dst))
+ break;
+ rcu_read_unlock();
/* if gateway was specified only delete the one hop */
if (cfg->fc_flags & RTF_GATEWAY)
return __ip6_del_rt_siblings(rt, cfg);
}
}
- read_unlock_bh(&table->tb6_lock);
+ rcu_read_unlock();
return err;
}
nrt->rt6i_protocol = RTPROT_REDIRECT;
nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
- if (ip6_ins_rt(nrt))
- goto out_release;
+ /* No need to remove rt from the exception table if rt is
+ * a cached route because rt6_insert_exception() will
+ * takes care of it
+ */
+ if (rt6_insert_exception(nrt, rt)) {
+ dst_release_immediate(&nrt->dst);
+ goto out;
+ }
netevent.old = &rt->dst;
netevent.new = &nrt->dst;
netevent.neigh = neigh;
call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
- if (rt->rt6i_flags & RTF_CACHE) {
- rt = (struct rt6_info *) dst_clone(&rt->dst);
- ip6_del_rt(rt);
- }
-
-out_release:
- /* Release the reference taken in
- * ip6_rt_cache_alloc()
- */
- dst_release(&nrt->dst);
-
out:
neigh_release(neigh);
}
if (!table)
return NULL;
- read_lock_bh(&table->tb6_lock);
- fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
+ rcu_read_lock();
+ fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0, true);
if (!fn)
goto out;
- for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
+ for_each_fib6_node_rt_rcu(fn) {
if (rt->dst.dev->ifindex != ifindex)
continue;
if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
continue;
if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
continue;
- dst_hold(&rt->dst);
+ ip6_hold_safe(NULL, &rt, false);
break;
}
out:
- read_unlock_bh(&table->tb6_lock);
+ rcu_read_unlock();
return rt;
}
if (!table)
return NULL;
- read_lock_bh(&table->tb6_lock);
- for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
+ rcu_read_lock();
+ for_each_fib6_node_rt_rcu(&table->tb6_root) {
if (dev == rt->dst.dev &&
((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
ipv6_addr_equal(&rt->rt6i_gateway, addr))
break;
}
if (rt)
- dst_hold(&rt->dst);
- read_unlock_bh(&table->tb6_lock);
+ ip6_hold_safe(NULL, &rt, false);
+ rcu_read_unlock();
return rt;
}
struct rt6_info *rt;
restart:
- read_lock_bh(&table->tb6_lock);
- for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
+ rcu_read_lock();
+ for_each_fib6_node_rt_rcu(&table->tb6_root) {
if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
(!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
- dst_hold(&rt->dst);
- read_unlock_bh(&table->tb6_lock);
- ip6_del_rt(rt);
+ if (dst_hold_safe(&rt->dst)) {
+ rcu_read_unlock();
+ ip6_del_rt(rt);
+ } else {
+ rcu_read_unlock();
+ }
goto restart;
}
}
- read_unlock_bh(&table->tb6_lock);
+ rcu_read_unlock();
table->flags &= ~RT6_TABLE_HAS_DFLT_ROUTER;
}
if (((void *)rt->dst.dev == dev || !dev) &&
rt != net->ipv6.ip6_null_entry &&
ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
+ spin_lock_bh(&rt6_exception_lock);
/* remove prefsrc entry */
rt->rt6i_prefsrc.plen = 0;
+ /* need to update cache as well */
+ rt6_exceptions_remove_prefsrc(rt);
+ spin_unlock_bh(&rt6_exception_lock);
}
return 0;
}
}
#define RTF_RA_ROUTER (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
-#define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE)
/* Remove routers and update dst entries when gateway turn into host. */
static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
{
struct in6_addr *gateway = (struct in6_addr *)arg;
- if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
- ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
- ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
+ if (((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) &&
+ ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
return -1;
}
+
+ /* Further clean up cached routes in exception table.
+ * This is needed because cached route may have a different
+ * gateway than its 'parent' in the case of an ip redirect.
+ */
+ rt6_exceptions_clean_tohost(rt, gateway);
+
return 0;
}
if (rt->dst.dev == arg->dev &&
dst_metric_raw(&rt->dst, RTAX_MTU) &&
!dst_metric_locked(&rt->dst, RTAX_MTU)) {
- if (rt->rt6i_flags & RTF_CACHE) {
- /* For RTF_CACHE with rt6i_pmtu == 0
- * (i.e. a redirected route),
- * the metrics of its rt->dst.from has already
- * been updated.
- */
- if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
- rt->rt6i_pmtu = arg->mtu;
- } else if (dst_mtu(&rt->dst) >= arg->mtu ||
- (dst_mtu(&rt->dst) < arg->mtu &&
- dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
+ spin_lock_bh(&rt6_exception_lock);
+ if (dst_mtu(&rt->dst) >= arg->mtu ||
+ (dst_mtu(&rt->dst) < arg->mtu &&
+ dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
}
+ rt6_exceptions_update_pmtu(rt, arg->mtu);
+ spin_unlock_bh(&rt6_exception_lock);
}
return 0;
}
seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
net->ipv6.rt6_stats->fib_nodes,
net->ipv6.rt6_stats->fib_route_nodes,
- net->ipv6.rt6_stats->fib_rt_alloc,
+ atomic_read(&net->ipv6.rt6_stats->fib_rt_alloc),
net->ipv6.rt6_stats->fib_rt_entries,
net->ipv6.rt6_stats->fib_rt_cache,
dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
git.samba.org / sfrench / cifs-2.6.git / blobdiff