percpu: add __percpu sparse annotations to net

Add __percpu sparse annotations to net.

These annotations are to make sparse consider percpu variables to be
in a different address space and warn if accessed without going
through percpu accessors.  This patch doesn't affect normal builds.

The macro and type tricks around snmp stats make things a bit
interesting.  DEFINE/DECLARE_SNMP_STAT() macros mark the target field
as __percpu and SNMP_UPD_PO_STATS() macro is updated accordingly.  All
snmp_mib_*() users which used to cast the argument to (void **) are
updated to cast it to (void __percpu **).

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Vlad Yasevich <vladislav.yasevich@hp.com>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 23 insertions, 23 deletions

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 7d12c6a9b19..33b7dffa773 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1385,7 +1385,7 @@ int inet_ctl_sock_create(struct sock **sk, unsigned short family,
 }
 EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
 
-unsigned long snmp_fold_field(void *mib[], int offt)
+unsigned long snmp_fold_field(void __percpu *mib[], int offt)
 {
         unsigned long res = 0;
         int i;
@@ -1398,7 +1398,7 @@ unsigned long snmp_fold_field(void *mib[], int offt)
 }
 EXPORT_SYMBOL_GPL(snmp_fold_field);
 
-int snmp_mib_init(void *ptr[2], size_t mibsize)
+int snmp_mib_init(void __percpu *ptr[2], size_t mibsize)
 {
         BUG_ON(ptr == NULL);
         ptr[0] = __alloc_percpu(mibsize, __alignof__(unsigned long long));
@@ -1416,7 +1416,7 @@ err0:
 }
 EXPORT_SYMBOL_GPL(snmp_mib_init);
 
-void snmp_mib_free(void *ptr[2])
+void snmp_mib_free(void __percpu *ptr[2])
 {
         BUG_ON(ptr == NULL);
         free_percpu(ptr[0]);
@@ -1460,25 +1460,25 @@ static const struct net_protocol icmp_protocol = {
 
 static __net_init int ipv4_mib_init_net(struct net *net)
 {
-        if (snmp_mib_init((void **)net->mib.tcp_statistics,
+        if (snmp_mib_init((void __percpu **)net->mib.tcp_statistics,
                           sizeof(struct tcp_mib)) < 0)
                 goto err_tcp_mib;
-        if (snmp_mib_init((void **)net->mib.ip_statistics,
+        if (snmp_mib_init((void __percpu **)net->mib.ip_statistics,
                           sizeof(struct ipstats_mib)) < 0)
                 goto err_ip_mib;
-        if (snmp_mib_init((void **)net->mib.net_statistics,
+        if (snmp_mib_init((void __percpu **)net->mib.net_statistics,
                           sizeof(struct linux_mib)) < 0)
                 goto err_net_mib;
-        if (snmp_mib_init((void **)net->mib.udp_statistics,
+        if (snmp_mib_init((void __percpu **)net->mib.udp_statistics,
                           sizeof(struct udp_mib)) < 0)
                 goto err_udp_mib;
-        if (snmp_mib_init((void **)net->mib.udplite_statistics,
+        if (snmp_mib_init((void __percpu **)net->mib.udplite_statistics,
                           sizeof(struct udp_mib)) < 0)
                 goto err_udplite_mib;
-        if (snmp_mib_init((void **)net->mib.icmp_statistics,
+        if (snmp_mib_init((void __percpu **)net->mib.icmp_statistics,
                           sizeof(struct icmp_mib)) < 0)
                 goto err_icmp_mib;
-        if (snmp_mib_init((void **)net->mib.icmpmsg_statistics,
+        if (snmp_mib_init((void __percpu **)net->mib.icmpmsg_statistics,
                           sizeof(struct icmpmsg_mib)) < 0)
                 goto err_icmpmsg_mib;
 
@@ -1486,30 +1486,30 @@ static __net_init int ipv4_mib_init_net(struct net *net)
         return 0;
 
 err_icmpmsg_mib:
-        snmp_mib_free((void **)net->mib.icmp_statistics);
+        snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
 err_icmp_mib:
-        snmp_mib_free((void **)net->mib.udplite_statistics);
+        snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
 err_udplite_mib:
-        snmp_mib_free((void **)net->mib.udp_statistics);
+        snmp_mib_free((void __percpu **)net->mib.udp_statistics);
 err_udp_mib:
-        snmp_mib_free((void **)net->mib.net_statistics);
+        snmp_mib_free((void __percpu **)net->mib.net_statistics);
 err_net_mib:
-        snmp_mib_free((void **)net->mib.ip_statistics);
+        snmp_mib_free((void __percpu **)net->mib.ip_statistics);
 err_ip_mib:
-        snmp_mib_free((void **)net->mib.tcp_statistics);
+        snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
 err_tcp_mib:
         return -ENOMEM;
 }
 
 static __net_exit void ipv4_mib_exit_net(struct net *net)
 {
-        snmp_mib_free((void **)net->mib.icmpmsg_statistics);
-        snmp_mib_free((void **)net->mib.icmp_statistics);
-        snmp_mib_free((void **)net->mib.udplite_statistics);
-        snmp_mib_free((void **)net->mib.udp_statistics);
-        snmp_mib_free((void **)net->mib.net_statistics);
-        snmp_mib_free((void **)net->mib.ip_statistics);
-        snmp_mib_free((void **)net->mib.tcp_statistics);
+        snmp_mib_free((void __percpu **)net->mib.icmpmsg_statistics);
+        snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
+        snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
+        snmp_mib_free((void __percpu **)net->mib.udp_statistics);
+        snmp_mib_free((void __percpu **)net->mib.net_statistics);
+        snmp_mib_free((void __percpu **)net->mib.ip_statistics);
+        snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
 }
 
 static __net_initdata struct pernet_operations ipv4_mib_ops = {