[PATCH v4 05/10] lockd: Plumb nfs_open_context into nlm client unlock

[Benjamin Coddington <bcodding@redhat.com>]

We cannot depend on a file_lock->fl_file still being around while
performing unlocks for NFSv2 and NFSv3.  Pass along the nfs_open_context to
provide the necessary inode and credential to complete the unlock.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
---
 fs/lockd/clntproc.c        |   16 ++++++++++------
 fs/nfs/nfs3proc.c          |    4 +---
 fs/nfs/proc.c              |    4 +---
 include/linux/lockd/bind.h |    3 ++-
 4 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c
index 1129520..72b65c4 100644
--- a/fs/lockd/clntproc.c
+++ b/fs/lockd/clntproc.c
@@ -25,7 +25,8 @@
 
 static int	nlmclnt_test(struct nlm_rqst *, struct file_lock *);
 static int	nlmclnt_lock(struct nlm_rqst *, struct file_lock *);
-static int	nlmclnt_unlock(struct nlm_rqst *, struct file_lock *);
+static int	nlmclnt_unlock(struct nfs_open_context *nfs,
+		struct nlm_rqst *, struct file_lock *);
 static int	nlm_stat_to_errno(__be32 stat);
 static void	nlmclnt_locks_init_private(struct file_lock *fl, struct nlm_host *host);
 static int	nlmclnt_cancel(struct nlm_host *, int , struct file_lock *);
@@ -147,13 +148,15 @@ static void nlmclnt_release_lockargs(struct nlm_rqst *req)
 
 /**
  * nlmclnt_proc - Perform a single client-side lock request
- * @host: address of a valid nlm_host context representing the NLM server
+ * @ctx: address of the nfs_open_context for lock to operate upon
  * @cmd: fcntl-style file lock operation to perform
  * @fl: address of arguments for the lock operation
  *
  */
-int nlmclnt_proc(struct nlm_host *host, int cmd, struct file_lock *fl)
+int nlmclnt_proc(struct nfs_open_context *ctx, int cmd, struct file_lock *fl)
 {
+	struct inode		*inode = d_inode(ctx->dentry);
+	struct nlm_host		*host = NFS_SERVER(inode)->nlm_host;
 	struct nlm_rqst		*call;
 	int			status;
 
@@ -175,7 +178,7 @@ int nlmclnt_proc(struct nlm_host *host, int cmd, struct file_lock *fl)
 			call->a_args.block = IS_SETLKW(cmd) ? 1 : 0;
 			status = nlmclnt_lock(call, fl);
 		} else
-			status = nlmclnt_unlock(call, fl);
+			status = nlmclnt_unlock(ctx, call, fl);
 	} else if (IS_GETLK(cmd))
 		status = nlmclnt_test(call, fl);
 	else
@@ -646,7 +649,8 @@ nlmclnt_reclaim(struct nlm_host *host, struct file_lock *fl,
  * UNLOCK: remove an existing lock
  */
 static int
-nlmclnt_unlock(struct nlm_rqst *req, struct file_lock *fl)
+nlmclnt_unlock(struct nfs_open_context *ctx,
+		struct nlm_rqst *req, struct file_lock *fl)
 {
 	struct nlm_host	*host = req->a_host;
 	struct nlm_res	*resp = &req->a_res;
@@ -669,7 +673,7 @@ nlmclnt_unlock(struct nlm_rqst *req, struct file_lock *fl)
 	}
 
 	atomic_inc(&req->a_count);
-	status = nlmclnt_async_call(nfs_file_cred(fl->fl_file), req,
+	status = nlmclnt_async_call(ctx->cred, req,
 			NLMPROC_UNLOCK, &nlmclnt_unlock_ops);
 	if (status < 0)
 		goto out;
diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c
index a10e147..2941ab7 100644
--- a/fs/nfs/nfs3proc.c
+++ b/fs/nfs/nfs3proc.c
@@ -868,9 +868,7 @@ static void nfs3_proc_commit_setup(struct nfs_commit_data *data, struct rpc_mess
 static int
 nfs3_proc_lock(struct nfs_open_context *ctx, int cmd, struct file_lock *fl)
 {
-	struct inode *inode = d_inode(ctx->dentry);
-
-	return nlmclnt_proc(NFS_SERVER(inode)->nlm_host, cmd, fl);
+	return nlmclnt_proc(ctx, cmd, fl);
 }
 
 static int nfs3_have_delegation(struct inode *inode, fmode_t flags)
diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c
index 185deb9..17d892e 100644
--- a/fs/nfs/proc.c
+++ b/fs/nfs/proc.c
@@ -636,9 +636,7 @@ nfs_proc_commit_setup(struct nfs_commit_data *data, struct rpc_message *msg)
 static int
 nfs_proc_lock(struct nfs_open_context *ctx, int cmd, struct file_lock *fl)
 {
-	struct inode *inode = d_inode(ctx->dentry);
-
-	return nlmclnt_proc(NFS_SERVER(inode)->nlm_host, cmd, fl);
+	return nlmclnt_proc(ctx, cmd, fl);
 }
 
 /* Helper functions for NFS lock bounds checking */
diff --git a/include/linux/lockd/bind.h b/include/linux/lockd/bind.h
index 4d24d64..1d62e85 100644
--- a/include/linux/lockd/bind.h
+++ b/include/linux/lockd/bind.h
@@ -18,6 +18,7 @@
 
 /* Dummy declarations */
 struct svc_rqst;
+struct nfs_open_context;
 
 /*
  * This is the set of functions for lockd->nfsd communication
@@ -52,7 +53,7 @@ struct nlmclnt_initdata {
 extern struct nlm_host *nlmclnt_init(const struct nlmclnt_initdata *nlm_init);
 extern void	nlmclnt_done(struct nlm_host *host);
 
-extern int	nlmclnt_proc(struct nlm_host *host, int cmd,
+extern int	nlmclnt_proc(struct nfs_open_context *ctx, int cmd,
 					struct file_lock *fl);
 extern int	lockd_up(struct net *net);
 extern void	lockd_down(struct net *net);
-- 
1.7.1