Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit dad2b015 authored by Jeff Layton's avatar Jeff Layton Committed by Trond Myklebust
Browse files

nfs: fix RCU cl_xprt handling in nfs_swap_activate/deactivate 



sparse says:

fs/nfs/file.c:543:60: warning: incorrect type in argument 1 (different address spaces)
fs/nfs/file.c:543:60:    expected struct rpc_xprt *xprt
fs/nfs/file.c:543:60:    got struct rpc_xprt [noderef] <asn:4>*cl_xprt
fs/nfs/file.c:548:53: warning: incorrect type in argument 1 (different address spaces)
fs/nfs/file.c:548:53:    expected struct rpc_xprt *xprt
fs/nfs/file.c:548:53:    got struct rpc_xprt [noderef] <asn:4>*cl_xprt

cl_xprt is RCU-managed, so we need to take care to dereference and use
it while holding the RCU read lock.

Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: default avatarJeff Layton <jlayton@primarydata.com>
Signed-off-by: default avatarTrond Myklebust <trond.myklebust@primarydata.com>
parent 08a899d5

fs/nfs/file.c

+14 −2
Original line number Diff line number Diff line
@@ -546,13 +546,25 @@ static int nfs_launder_page(struct page *page) 
static int nfs_swap_activate(struct swap_info_struct *sis, struct file *file,

						sector_t *span)

{

	int ret;

	struct rpc_clnt *clnt = NFS_CLIENT(file->f_mapping->host);



	*span = sis->pages;

	return xs_swapper(NFS_CLIENT(file->f_mapping->host)->cl_xprt, 1);



	rcu_read_lock();

	ret = xs_swapper(rcu_dereference(clnt->cl_xprt), 1);

	rcu_read_unlock();



	return ret;

}



static void nfs_swap_deactivate(struct file *file)

{

	xs_swapper(NFS_CLIENT(file->f_mapping->host)->cl_xprt, 0);

	struct rpc_clnt *clnt = NFS_CLIENT(file->f_mapping->host);



	rcu_read_lock();

	xs_swapper(rcu_dereference(clnt->cl_xprt), 0);

	rcu_read_unlock();

}

#endif