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>

1 files changed, 3 insertions, 3 deletions

diff --git a/fs/afs/cell.c b/fs/afs/cell.c
index 4235a05afc76..69b95faacc5e 100644
--- a/fs/afs/cell.c
+++ b/fs/afs/cell.c
@@ -18,7 +18,7 @@
 #include <keys/rxrpc-type.h>
 #include "internal.h"
 
-unsigned __read_mostly afs_cell_gc_delay = 10;
+static unsigned __read_mostly afs_cell_gc_delay = 10;
 
 static void afs_manage_cell(struct work_struct *);
 
@@ -75,7 +75,7 @@ struct afs_cell *afs_lookup_cell_rcu(struct afs_net *net,
 			cell = rcu_dereference_raw(net->ws_cell);
 			if (cell) {
 				afs_get_cell(cell);
-				continue;
+				break;
 			}
 			ret = -EDESTADDRREQ;
 			continue;
@@ -411,7 +411,7 @@ static void afs_cell_destroy(struct rcu_head *rcu)
 
 	ASSERTCMP(atomic_read(&cell->usage), ==, 0);
 
-	afs_put_addrlist(cell->vl_addrs);
+	afs_put_addrlist(rcu_access_pointer(cell->vl_addrs));
 	key_put(cell->anonymous_key);
 	kfree(cell);