1 files changed, 65 insertions, 108 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index fdcebfce5fdb..a64ee08aadb2 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -878,29 +878,34 @@ nfs4_inc_and_copy_stateid(stateid_t *dst, struct nfs4_stid *stid)
 	spin_unlock(&stid->sc_lock);
 }
 
-static void nfs4_put_deleg_lease(struct nfs4_delegation *dp)
+static void put_deleg_file(struct nfs4_file *fp)
 {
 	struct file *filp = NULL;
-	struct nfs4_file *fp = dp->dl_stid.sc_file;
-
-	WARN_ON_ONCE(!fp->fi_delegees);
 
 	spin_lock(&fp->fi_lock);
-	if (--fp->fi_delegees == 0) {
+	if (--fp->fi_delegees == 0)
 		swap(filp, fp->fi_deleg_file);
-	}
 	spin_unlock(&fp->fi_lock);
 
-	if (filp) {
-		vfs_setlease(filp, F_UNLCK, NULL, (void **)&dp);
+	if (filp)
 		fput(filp);
-	}
+}
+
+static void nfs4_unlock_deleg_lease(struct nfs4_delegation *dp)
+{
+	struct nfs4_file *fp = dp->dl_stid.sc_file;
+	struct file *filp = fp->fi_deleg_file;
+
+	WARN_ON_ONCE(!fp->fi_delegees);
+
+	vfs_setlease(filp, F_UNLCK, NULL, (void **)&dp);
+	put_deleg_file(fp);
 }
 
 static void destroy_unhashed_deleg(struct nfs4_delegation *dp)
 {
 	put_clnt_odstate(dp->dl_clnt_odstate);
-	nfs4_put_deleg_lease(dp);
+	nfs4_unlock_deleg_lease(dp);
 	nfs4_put_stid(&dp->dl_stid);
 }
 
@@ -959,7 +964,6 @@ hash_delegation_locked(struct nfs4_delegation *dp, struct nfs4_file *fp)
 
 	if (nfs4_delegation_exists(clp, fp))
 		return -EAGAIN;
-	++fp->fi_delegees;
 	refcount_inc(&dp->dl_stid.sc_count);
 	dp->dl_stid.sc_type = NFS4_DELEG_STID;
 	list_add(&dp->dl_perfile, &fp->fi_delegations);
@@ -3956,10 +3960,6 @@ nfsd_break_deleg_cb(struct file_lock *fl)
 	struct nfs4_delegation *dp = (struct nfs4_delegation *)fl->fl_owner;
 	struct nfs4_file *fp = dp->dl_stid.sc_file;
 
-	if (fp->fi_had_conflict) {
-		WARN(1, "duplicate break on %p\n", fp);
-		return ret;
-	}
 	/*
 	 * We don't want the locks code to timeout the lease for us;
 	 * we'll remove it ourself if a delegation isn't returned
@@ -3969,15 +3969,7 @@ nfsd_break_deleg_cb(struct file_lock *fl)
 
 	spin_lock(&fp->fi_lock);
 	fp->fi_had_conflict = true;
-	/*
-	 * If there are no delegations on the list, then return true
-	 * so that the lease code will go ahead and delete it.
-	 */
-	if (list_empty(&fp->fi_delegations))
-		ret = true;
-	else
-		list_for_each_entry(dp, &fp->fi_delegations, dl_perfile)
-			nfsd_break_one_deleg(dp);
+	nfsd_break_one_deleg(dp);
 	spin_unlock(&fp->fi_lock);
 	return ret;
 }
@@ -4315,121 +4307,86 @@ static struct file_lock *nfs4_alloc_init_lease(struct nfs4_delegation *dp,
 	fl->fl_end = OFFSET_MAX;
 	fl->fl_owner = (fl_owner_t)dp;
 	fl->fl_pid = current->tgid;
+	fl->fl_file = dp->dl_stid.sc_file->fi_deleg_file;
 	return fl;
 }
 
-/**
- * nfs4_setlease - Obtain a delegation by requesting lease from vfs layer
- * @dp:   a pointer to the nfs4_delegation we're adding.
- *
- * Return:
- *      On success: Return code will be 0 on success.
- *
- *      On error: -EAGAIN if there was an existing delegation.
- *                 nonzero if there is an error in other cases.
- *
- */
-
-static int nfs4_setlease(struct nfs4_delegation *dp)
-{
-	struct nfs4_file *fp = dp->dl_stid.sc_file;
-	struct file_lock *fl;
-	struct file *filp;
-	int status = 0;
-
-	fl = nfs4_alloc_init_lease(dp, NFS4_OPEN_DELEGATE_READ);
-	if (!fl)
-		return -ENOMEM;
-	filp = find_readable_file(fp);
-	if (!filp) {
-		/* We should always have a readable file here */
-		WARN_ON_ONCE(1);
-		locks_free_lock(fl);
-		return -EBADF;
-	}
-	fl->fl_file = filp;
-	status = vfs_setlease(filp, fl->fl_type, &fl, NULL);
-	if (fl)
-		locks_free_lock(fl);
-	if (status)
-		goto out_fput;
-	spin_lock(&state_lock);
-	spin_lock(&fp->fi_lock);
-	/* Did the lease get broken before we took the lock? */
-	status = -EAGAIN;
-	if (fp->fi_had_conflict)
-		goto out_unlock;
-	/* Race breaker */
-	if (fp->fi_deleg_file) {
-		status = hash_delegation_locked(dp, fp);
-		goto out_unlock;
-	}
-	fp->fi_deleg_file = filp;
-	fp->fi_delegees = 0;
-	status = hash_delegation_locked(dp, fp);
-	spin_unlock(&fp->fi_lock);
-	spin_unlock(&state_lock);
-	if (status) {
-		/* Should never happen, this is a new fi_deleg_file  */
-		WARN_ON_ONCE(1);
-		goto out_fput;
-	}
-	return 0;
-out_unlock:
-	spin_unlock(&fp->fi_lock);
-	spin_unlock(&state_lock);
-out_fput:
-	fput(filp);
-	return status;
-}
-
 static struct nfs4_delegation *
 nfs4_set_delegation(struct nfs4_client *clp, struct svc_fh *fh,
 		    struct nfs4_file *fp, struct nfs4_clnt_odstate *odstate)
 {
 	int status = 0;
 	struct nfs4_delegation *dp;
+	struct file *filp;
+	struct file_lock *fl;
 
+	/*
+	 * The fi_had_conflict and nfs_get_existing_delegation checks
+	 * here are just optimizations; we'll need to recheck them at
+	 * the end:
+	 */
 	if (fp->fi_had_conflict)
 		return ERR_PTR(-EAGAIN);
 
+	filp = find_readable_file(fp);
+	if (!filp) {
+		/* We should always have a readable file here */
+		WARN_ON_ONCE(1);
+		return ERR_PTR(-EBADF);
+	}
 	spin_lock(&state_lock);
 	spin_lock(&fp->fi_lock);
 	if (nfs4_delegation_exists(clp, fp))
 		status = -EAGAIN;
+	else if (!fp->fi_deleg_file) {
+		fp->fi_deleg_file = filp;
+		/* increment early to prevent fi_deleg_file from being
+		 * cleared */
+		fp->fi_delegees = 1;
+		filp = NULL;
+	} else
+		fp->fi_delegees++;
 	spin_unlock(&fp->fi_lock);
 	spin_unlock(&state_lock);
-
+	if (filp)
+		fput(filp);
 	if (status)
 		return ERR_PTR(status);
 
+	status = -ENOMEM;
 	dp = alloc_init_deleg(clp, fp, fh, odstate);
 	if (!dp)
-		return ERR_PTR(-ENOMEM);
+		goto out_delegees;
+
+	fl = nfs4_alloc_init_lease(dp, NFS4_OPEN_DELEGATE_READ);
+	if (!fl)
+		goto out_stid;
+
+	status = vfs_setlease(fp->fi_deleg_file, fl->fl_type, &fl, NULL);
+	if (fl)
+		locks_free_lock(fl);
+	if (status)
+		goto out_clnt_odstate;
 
 	spin_lock(&state_lock);
 	spin_lock(&fp->fi_lock);
-	if (!fp->fi_deleg_file) {
-		spin_unlock(&fp->fi_lock);
-		spin_unlock(&state_lock);
-		status = nfs4_setlease(dp);
-		goto out;
-	}
-	if (fp->fi_had_conflict) {
+	if (fp->fi_had_conflict)
 		status = -EAGAIN;
-		goto out_unlock;
-	}
-	status = hash_delegation_locked(dp, fp);
-out_unlock:
+	else
+		status = hash_delegation_locked(dp, fp);
 	spin_unlock(&fp->fi_lock);
 	spin_unlock(&state_lock);
-out:
-	if (status) {
-		put_clnt_odstate(dp->dl_clnt_odstate);
-		nfs4_put_stid(&dp->dl_stid);
-		return ERR_PTR(status);
-	}
+
+	if (status)
+		destroy_unhashed_deleg(dp);
 	return dp;
+out_clnt_odstate:
+	put_clnt_odstate(dp->dl_clnt_odstate);
+out_stid:
+	nfs4_put_stid(&dp->dl_stid);
+out_delegees:
+	put_deleg_file(fp);
+	return ERR_PTR(status);
 }
 
 static void nfsd4_open_deleg_none_ext(struct nfsd4_open *open, int status)