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, 8 insertions, 0 deletions

diff --git a/fs/afs/proc.c b/fs/afs/proc.c
index 4508dd54f789..1c95756335b7 100644
--- a/fs/afs/proc.c
+++ b/fs/afs/proc.c
@@ -183,6 +183,7 @@ static int afs_proc_cells_open(struct inode *inode, struct file *file)
  * first item
  */
 static void *afs_proc_cells_start(struct seq_file *m, loff_t *_pos)
+	__acquires(rcu)
 {
 	struct afs_net *net = afs_seq2net(m);
 
@@ -204,6 +205,7 @@ static void *afs_proc_cells_next(struct seq_file *m, void *v, loff_t *pos)
  * clean up after reading from the cells list
  */
 static void afs_proc_cells_stop(struct seq_file *m, void *v)
+	__releases(rcu)
 {
 	rcu_read_unlock();
 }
@@ -413,6 +415,7 @@ static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file)
  * first item
  */
 static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
+	__acquires(cell->proc_lock)
 {
 	struct afs_cell *cell = m->private;
 
@@ -438,6 +441,7 @@ static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
  * clean up after reading from the cells list
  */
 static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v)
+	__releases(cell->proc_lock)
 {
 	struct afs_cell *cell = p->private;
 
@@ -500,6 +504,7 @@ static int afs_proc_cell_vlservers_open(struct inode *inode, struct file *file)
  * first item
  */
 static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)
+	__acquires(rcu)
 {
 	struct afs_addr_list *alist;
 	struct afs_cell *cell = m->private;
@@ -544,6 +549,7 @@ static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
  * clean up after reading from the cells list
  */
 static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v)
+	__releases(rcu)
 {
 	rcu_read_unlock();
 }
@@ -580,6 +586,7 @@ static int afs_proc_servers_open(struct inode *inode, struct file *file)
  * first item.
  */
 static void *afs_proc_servers_start(struct seq_file *m, loff_t *_pos)
+	__acquires(rcu)
 {
 	struct afs_net *net = afs_seq2net(m);
 
@@ -601,6 +608,7 @@ static void *afs_proc_servers_next(struct seq_file *m, void *v, loff_t *_pos)
  * clean up after reading from the cells list
  */
 static void afs_proc_servers_stop(struct seq_file *p, void *v)
+	__releases(rcu)
 {
 	rcu_read_unlock();
 }