afs: Fix checker warnings
Fix warnings raised by checker, including:
(*) Warnings raised by unequal comparison for the purposes of sorting,
where the endianness doesn't matter:
fs/afs/addr_list.c:246:21: warning: restricted __be16 degrades to integer
fs/afs/addr_list.c:246:30: warning: restricted __be16 degrades to integer
fs/afs/addr_list.c:248:21: warning: restricted __be32 degrades to integer
fs/afs/addr_list.c:248:49: warning: restricted __be32 degrades to integer
fs/afs/addr_list.c:283:21: warning: restricted __be16 degrades to integer
fs/afs/addr_list.c:283:30: warning: restricted __be16 degrades to integer
(*) afs_set_cb_interest() is not actually used and can be removed.
(*) afs_cell_gc_delay() should be provided with a sysctl.
(*) afs_cell_destroy() needs to use rcu_access_pointer() to read
cell->vl_addrs.
(*) afs_init_fs_cursor() should be static.
(*) struct afs_vnode::permit_cache needs to be marked __rcu.
(*) afs_server_rcu() needs to use rcu_access_pointer().
(*) afs_destroy_server() should use rcu_access_pointer() on
server->addresses as the server object is no longer accessible.
(*) afs_find_server() casts __be16/__be32 values to int in order to
directly compare them for the purpose of finding a match in a list,
but is should also annotate the cast with __force to avoid checker
warnings.
(*) afs_check_permit() accesses vnode->permit_cache outside of the RCU
readlock, though it doesn't then access the value; the extraneous
access is deleted.
False positives:
(*) Conditional locking around the code in xdr_decode_AFSFetchStatus. This
can be dealt with in a separate patch.
fs/afs/fsclient.c:148:9: warning: context imbalance in 'xdr_decode_AFSFetchStatus' - different lock contexts for basic block
(*) Incorrect handling of seq-retry lock context balance:
fs/afs/inode.c:455:38: warning: context imbalance in 'afs_getattr' - different
lock contexts for basic block
fs/afs/server.c:52:17: warning: context imbalance in 'afs_find_server' - different lock contexts for basic block
fs/afs/server.c:128:17: warning: context imbalance in 'afs_find_server_by_uuid' - different lock contexts for basic block
Errors:
(*) afs_lookup_cell_rcu() needs to break out of the seq-retry loop, not go
round again if it successfully found the workstation cell.
(*) Fix UUID decode in afs_deliver_cb_probe_uuid().
(*) afs_cache_permit() has a missing rcu_read_unlock() before one of the
jumps to the someone_else_changed_it label. Move the unlock to after
the label.
(*) afs_vl_get_addrs_u() is using ntohl() rather than htonl() when
encoding to XDR.
(*) afs_deliver_yfsvl_get_endpoints() is using htonl() rather than ntohl()
when decoding from XDR.
Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/fs/afs/server.c b/fs/afs/server.c
index a43ef77..e23be63 100644
--- a/fs/afs/server.c
+++ b/fs/afs/server.c
@@ -59,7 +59,8 @@ struct afs_server *afs_find_server(struct afs_net *net,
alist = rcu_dereference(server->addresses);
for (i = alist->nr_ipv4; i < alist->nr_addrs; i++) {
b = &alist->addrs[i].transport.sin6;
- diff = (u16)a->sin6_port - (u16)b->sin6_port;
+ diff = ((u16 __force)a->sin6_port -
+ (u16 __force)b->sin6_port);
if (diff == 0)
diff = memcmp(&a->sin6_addr,
&b->sin6_addr,
@@ -79,10 +80,11 @@ struct afs_server *afs_find_server(struct afs_net *net,
alist = rcu_dereference(server->addresses);
for (i = 0; i < alist->nr_ipv4; i++) {
b = &alist->addrs[i].transport.sin6;
- diff = (u16)a->sin6_port - (u16)b->sin6_port;
+ diff = ((u16 __force)a->sin6_port -
+ (u16 __force)b->sin6_port);
if (diff == 0)
- diff = ((u32)a->sin6_addr.s6_addr32[3] -
- (u32)b->sin6_addr.s6_addr32[3]);
+ diff = ((u32 __force)a->sin6_addr.s6_addr32[3] -
+ (u32 __force)b->sin6_addr.s6_addr32[3]);
if (diff == 0)
goto found;
if (diff < 0) {
@@ -381,7 +383,7 @@ static void afs_server_rcu(struct rcu_head *rcu)
{
struct afs_server *server = container_of(rcu, struct afs_server, rcu);
- afs_put_addrlist(server->addresses);
+ afs_put_addrlist(rcu_access_pointer(server->addresses));
kfree(server);
}
@@ -390,7 +392,7 @@ static void afs_server_rcu(struct rcu_head *rcu)
*/
static void afs_destroy_server(struct afs_net *net, struct afs_server *server)
{
- struct afs_addr_list *alist = server->addresses;
+ struct afs_addr_list *alist = rcu_access_pointer(server->addresses);
struct afs_addr_cursor ac = {
.alist = alist,
.addr = &alist->addrs[0],