Return-Path: linux-nfs-owner@vger.kernel.org Received: from cantor2.suse.de ([195.135.220.15]:38857 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751041AbaDPETh (ORCPT ); Wed, 16 Apr 2014 00:19:37 -0400 From: NeilBrown To: linux-mm@kvack.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Date: Wed, 16 Apr 2014 14:03:37 +1000 Subject: [PATCH 15/19] nfsd: set PF_FSTRANS when client_mutex is held. Cc: xfs@oss.sgi.com Message-ID: <20140416040336.10604.67828.stgit@notabene.brown> In-Reply-To: <20140416033623.10604.69237.stgit@notabene.brown> References: <20140416033623.10604.69237.stgit@notabene.brown> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: When loop-back NFS with NFSv4 is in use, client_mutex might be needed to reclaim memory, so any memory allocation while client_mutex is held must avoid __GFP_FS, so best to set PF_FSTRANS. Signed-off-by: NeilBrown --- fs/nfsd/nfs4state.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index d5d070fbeb35..7b7fbcbe20cb 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -75,6 +75,7 @@ static int check_for_locks(struct nfs4_file *filp, struct nfs4_lockowner *lowner /* Currently used for almost all code touching nfsv4 state: */ static DEFINE_MUTEX(client_mutex); +static unsigned int client_mutex_pflags; /* * Currently used for the del_recall_lru and file hash table. In an @@ -93,6 +94,7 @@ void nfs4_lock_state(void) { mutex_lock(&client_mutex); + current_set_flags_nested(&client_mutex_pflags, PF_FSTRANS); } static void free_session(struct nfsd4_session *); @@ -127,6 +129,7 @@ static __be32 nfsd4_get_session_locked(struct nfsd4_session *ses) void nfs4_unlock_state(void) { + current_restore_flags_nested(&client_mutex_pflags, PF_FSTRANS); mutex_unlock(&client_mutex); }