[NET]: Add some acquires/releases sparse annotations.

Add __acquires() and __releases() annotations to suppress some sparse
warnings.

example of warnings :

net/ipv4/udp.c:1555:14: warning: context imbalance in 'udp_seq_start' - wrong
count at exit
net/ipv4/udp.c:1571:13: warning: context imbalance in 'udp_seq_stop' -
unexpected unlock

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 8 insertions, 0 deletions

diff --git a/net/ipv6/anycast.c b/net/ipv6/anycast.c
index f915c4df9820..5c4190060e75 100644
--- a/net/ipv6/anycast.c
+++ b/net/ipv6/anycast.c
@@ -504,6 +504,7 @@ static struct ifacaddr6 *ac6_get_idx(struct seq_file *seq, loff_t pos)
 }
 
 static void *ac6_seq_start(struct seq_file *seq, loff_t *pos)
+        __acquires(dev_base_lock)
 {
         read_lock(&dev_base_lock);
         return ac6_get_idx(seq, *pos);
@@ -518,6 +519,7 @@ static void *ac6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 }
 
 static void ac6_seq_stop(struct seq_file *seq, void *v)
+        __releases(dev_base_lock)
 {
         struct ac6_iter_state *state = ac6_seq_private(seq);
         if (likely(state->idev != NULL)) {
diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c
index d0babea89819..2b7d9ee98832 100644
--- a/net/ipv6/ip6_flowlabel.c
+++ b/net/ipv6/ip6_flowlabel.c
@@ -629,6 +629,7 @@ static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos)
 }
 
 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos)
+        __acquires(ip6_fl_lock)
 {
         read_lock_bh(&ip6_fl_lock);
         return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
@@ -647,6 +648,7 @@ static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 }
 
 static void ip6fl_seq_stop(struct seq_file *seq, void *v)
+        __releases(ip6_fl_lock)
 {
         read_unlock_bh(&ip6_fl_lock);
 }
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 82b12940c2a0..ab228d1ea114 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -2373,6 +2373,7 @@ static struct ifmcaddr6 *igmp6_mc_get_idx(struct seq_file *seq, loff_t pos)
 }
 
 static void *igmp6_mc_seq_start(struct seq_file *seq, loff_t *pos)
+        __acquires(dev_base_lock)
 {
         read_lock(&dev_base_lock);
         return igmp6_mc_get_idx(seq, *pos);
@@ -2387,6 +2388,7 @@ static void *igmp6_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 }
 
 static void igmp6_mc_seq_stop(struct seq_file *seq, void *v)
+        __releases(dev_base_lock)
 {
         struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
         if (likely(state->idev != NULL)) {
@@ -2516,6 +2518,7 @@ static struct ip6_sf_list *igmp6_mcf_get_idx(struct seq_file *seq, loff_t pos)
 }
 
 static void *igmp6_mcf_seq_start(struct seq_file *seq, loff_t *pos)
+        __acquires(dev_base_lock)
 {
         read_lock(&dev_base_lock);
         return *pos ? igmp6_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
@@ -2533,6 +2536,7 @@ static void *igmp6_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 }
 
 static void igmp6_mcf_seq_stop(struct seq_file *seq, void *v)
+        __releases(dev_base_lock)
 {
         struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
         if (likely(state->im != NULL)) {