[Devel] [PATCH RHEL7 COMMIT] fuse kio: Use __maybe_unused

[Konstantin Khorenko]

The commit is pushed to "branch-rh7-3.10.0-862.14.4.vz7.72.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh7-3.10.0-862.14.4.vz7.72.9
------>
commit b7f9b4aaa9c9828f40c79d496cfe4dc3e9c04db4
Author: Kirill Tkhai <ktkhai at virtuozzo.com>
Date:   Tue Oct 16 18:04:29 2018 +0300

    fuse kio: Use __maybe_unused
    
    Signed-off-by: Kirill Tkhai <ktkhai at virtuozzo.com>
    Reviewed-by: Pavel Butsykin <pbutsykin at virtuozzo.com>
    
    =====================
    Patchset description:
    
    Order pcs_rpc and pcs_sockio destruction and close leaked socket
    
    https://pmc.acronis.com/browse/VSTOR-15305
    
    Ploop can asynchronously unmap regions by sending IOCB_CMD_UNMAP_ITER, but this
    command isn't quite correctly interpreted in Fuse. Moreover, in Fast-path mode,
    fallocate(FALLOC_FL_PUNCH_HOLE|FALLOC_FL_ZERO_RANGE) falls to fuse user daemon
    and it can lead to data corruption.
    
    Let's fix it.
    
    Kirill Tkhai (9):
          fuse kio: Use __maybe_unused
          fuse kio: Use sio eof instead of parent to determ abort
          fuse kio: Reorder callback assignment
          fuse kio: Add pcs_cleanup_wq
          fuse kio: Destroy rpc in work func
          fuse kio: Introduce pcs_sk_kick_queue()
          fuse kio: Dereference sk_user_data under rcu
          fuse kio: Fix rpc socket leak on rpc_abort()
          fuse kio: Hold pcs_rpc counter till sio may be freed
---
 fs/fuse/kio/pcs/pcs_sock_io.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/fs/fuse/kio/pcs/pcs_sock_io.c b/fs/fuse/kio/pcs/pcs_sock_io.c
index 0cf392fb4703..18b66f99e018 100644
--- a/fs/fuse/kio/pcs/pcs_sock_io.c
+++ b/fs/fuse/kio/pcs/pcs_sock_io.c
@@ -212,7 +212,6 @@ static void pcs_sockio_recv(struct pcs_sockio *sio)
 	u32 msg_size;
 	unsigned long loop_timeout = jiffies + PCS_SIO_SLICE;
 
-	(void)ep;
 	TRACE("ENTER:" PEER_FMT " sio:%p cur_msg:%p\n", PEER_ARGS(ep), sio, sio->current_msg);
 
 	while(!test_bit(PCS_IOCONN_BF_DEAD, &conn->flags)) {
@@ -316,14 +315,13 @@ static void pcs_sockio_recv(struct pcs_sockio *sio)
 
 static void pcs_sockio_send(struct pcs_sockio *sio)
 {
+	struct pcs_rpc *ep __maybe_unused = sio->parent;
 	struct pcs_ioconn* conn = &sio->ioconn;
 	struct iov_iter *it = &sio->write_iter;
 	unsigned long loop_timeout = jiffies + PCS_SIO_SLICE;
 	struct pcs_msg * msg;
 	int done = 0;
 	int count = 0;
-	struct pcs_rpc *ep = sio->parent;
-	(void)ep;
 
 	while (!list_empty(&sio->write_queue)) {
 		msg = list_first_entry(&sio->write_queue, struct pcs_msg, list);