MFC r312432:

Add a mount option for tmpfs(5) to not use namecache.

5 files changed, 54 insertions, 17 deletions

diff --git a/sys/fs/tmpfs/tmpfs.h b/sys/fs/tmpfs/tmpfs.h
index 8661f42..37e5bbb 100644
--- a/sys/fs/tmpfs/tmpfs.h
+++ b/sys/fs/tmpfs/tmpfs.h
@@ -383,7 +383,9 @@ struct tmpfs_mount {
 	uma_zone_t		tm_node_pool;
 
 	/* Read-only status. */
-	int			tm_ronly;
+	bool			tm_ronly;
+	/* Do not use namecache. */
+	bool			tm_nonc;
 };
 #define	TMPFS_LOCK(tm) mtx_lock(&(tm)->tm_allnode_lock)
 #define	TMPFS_UNLOCK(tm) mtx_unlock(&(tm)->tm_allnode_lock)
@@ -528,4 +530,11 @@ VP_TO_TMPFS_DIR(struct vnode *vp)
 	return (node);
 }
 
+static inline bool
+tmpfs_use_nc(struct vnode *vp)
+{
+
+	return (!(VFS_TO_TMPFS(vp->v_mount)->tm_nonc));
+}
+
 #endif /* _FS_TMPFS_TMPFS_H_ */
diff --git a/sys/fs/tmpfs/tmpfs_subr.c b/sys/fs/tmpfs/tmpfs_subr.c
index 9cefba3..816b3cc 100644
--- a/sys/fs/tmpfs/tmpfs_subr.c
+++ b/sys/fs/tmpfs/tmpfs_subr.c
@@ -591,7 +591,8 @@ loop:
 	TMPFS_NODE_UNLOCK(node);
 
 	/* Get a new vnode and associate it with our node. */
-	error = getnewvnode("tmpfs", mp, &tmpfs_vnodeop_entries, &vp);
+	error = getnewvnode("tmpfs", mp, VFS_TO_TMPFS(mp)->tm_nonc ?
+	    &tmpfs_vnodeop_nonc_entries : &tmpfs_vnodeop_entries, &vp);
 	if (error != 0)
 		goto unlock;
 	MPASS(vp != NULL);
diff --git a/sys/fs/tmpfs/tmpfs_vfsops.c b/sys/fs/tmpfs/tmpfs_vfsops.c
index 037d3fc..65a2a12 100644
--- a/sys/fs/tmpfs/tmpfs_vfsops.c
+++ b/sys/fs/tmpfs/tmpfs_vfsops.c
@@ -78,7 +78,7 @@ static int	tmpfs_statfs(struct mount *, struct statfs *);
 
 static const char *tmpfs_opts[] = {
 	"from", "size", "maxfilesize", "inodes", "uid", "gid", "mode", "export",
-	"union", NULL
+	"union", "nonc", NULL
 };
 
 static const char *tmpfs_updateopts[] = {
@@ -137,6 +137,7 @@ tmpfs_mount(struct mount *mp)
 	struct tmpfs_node *root;
 	struct thread *td = curthread;
 	int error;
+	bool nonc;
 	/* Size counters. */
 	u_quad_t pages;
 	off_t nodes_max, size_max, maxfilesize;
@@ -185,6 +186,7 @@ tmpfs_mount(struct mount *mp)
 		size_max = 0;
 	if (vfs_getopt_size(mp->mnt_optnew, "maxfilesize", &maxfilesize) != 0)
 		maxfilesize = 0;
+	nonc = vfs_getopt(mp->mnt_optnew, "nonc", NULL, NULL) == 0;
 
 	/* Do not allow mounts if we do not have enough memory to preserve
 	 * the minimum reserved pages. */
@@ -235,6 +237,7 @@ tmpfs_mount(struct mount *mp)
 	    sizeof(struct tmpfs_node), tmpfs_node_ctor, tmpfs_node_dtor,
 	    tmpfs_node_init, tmpfs_node_fini, UMA_ALIGN_PTR, 0);
 	tmp->tm_ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
+	tmp->tm_nonc = nonc;
 
 	/* Allocate the root node. */
 	error = tmpfs_alloc_node(mp, tmp, VDIR, root_uid, root_gid,
diff --git a/sys/fs/tmpfs/tmpfs_vnops.c b/sys/fs/tmpfs/tmpfs_vnops.c
index 9b8c460..6d6982f 100644
--- a/sys/fs/tmpfs/tmpfs_vnops.c
+++ b/sys/fs/tmpfs/tmpfs_vnops.c
@@ -76,11 +76,8 @@ tmpfs_vn_get_ino_alloc(struct mount *mp, void *arg, int lkflags,
 }
 
 static int
-tmpfs_lookup(struct vop_cachedlookup_args *v)
+tmpfs_lookup1(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp)
 {
-	struct vnode *dvp = v->a_dvp;
-	struct vnode **vpp = v->a_vpp;
-	struct componentname *cnp = v->a_cnp;
 	struct tmpfs_dirent *de;
 	struct tmpfs_node *dnode, *pnode;
 	struct tmpfs_mount *tm;
@@ -213,7 +210,7 @@ tmpfs_lookup(struct vop_cachedlookup_args *v)
 	 * request was for creation, as it does not improve timings on
 	 * emprical tests.
 	 */
-	if ((cnp->cn_flags & MAKEENTRY) != 0)
+	if ((cnp->cn_flags & MAKEENTRY) != 0 && tmpfs_use_nc(dvp))
 		cache_enter(dvp, *vpp, cnp);
 
 out:
@@ -227,6 +224,20 @@ out:
 }
 
 static int
+tmpfs_cached_lookup(struct vop_cachedlookup_args *v)
+{
+
+	return (tmpfs_lookup1(v->a_dvp, v->a_vpp, v->a_cnp));
+}
+
+static int
+tmpfs_lookup(struct vop_lookup_args *v)
+{
+
+	return (tmpfs_lookup1(v->a_dvp, v->a_vpp, v->a_cnp));
+}
+
+static int
 tmpfs_create(struct vop_create_args *v)
 {
 	struct vnode *dvp = v->a_dvp;
@@ -238,7 +249,7 @@ tmpfs_create(struct vop_create_args *v)
 	MPASS(vap->va_type == VREG || vap->va_type == VSOCK);
 
 	error = tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL);
-	if (error == 0 && (cnp->cn_flags & MAKEENTRY) != 0)
+	if (error == 0 && (cnp->cn_flags & MAKEENTRY) != 0 && tmpfs_use_nc(dvp))
 		cache_enter(dvp, *vpp, cnp);
 	return (error);
 }
@@ -1009,10 +1020,12 @@ tmpfs_rename(struct vop_rename_args *v)
 
 	tmpfs_dir_attach(tdvp, de);
 
-	cache_purge(fvp);
-	if (tvp != NULL)
-		cache_purge(tvp);
-	cache_purge_negative(tdvp);
+	if (tmpfs_use_nc(fvp)) {
+		cache_purge(fvp);
+		if (tvp != NULL)
+			cache_purge(tvp);
+		cache_purge_negative(tdvp);
+	}
 
 	error = 0;
 
@@ -1125,8 +1138,10 @@ tmpfs_rmdir(struct vop_rmdir_args *v)
 	    TMPFS_NODE_MODIFIED;
 	TMPFS_NODE_UNLOCK(dnode);
 
-	cache_purge(dvp);
-	cache_purge(vp);
+	if (tmpfs_use_nc(dvp)) {
+		cache_purge(dvp);
+		cache_purge(vp);
+	}
 
 	/* Free the directory entry we just deleted.  Note that the node
 	 * referred by it will not be removed until the vnode is really
@@ -1270,7 +1285,8 @@ tmpfs_reclaim(struct vop_reclaim_args *v)
 	else
 		vnode_destroy_vobject(vp);
 	vp->v_object = NULL;
-	cache_purge(vp);
+	if (tmpfs_use_nc(vp))
+		cache_purge(vp);
 
 	TMPFS_NODE_LOCK(node);
 	tmpfs_free_vp(vp);
@@ -1534,7 +1550,7 @@ restart:
 struct vop_vector tmpfs_vnodeop_entries = {
 	.vop_default =			&default_vnodeops,
 	.vop_lookup =			vfs_cache_lookup,
-	.vop_cachedlookup =		tmpfs_lookup,
+	.vop_cachedlookup =		tmpfs_cached_lookup,
 	.vop_create =			tmpfs_create,
 	.vop_mknod =			tmpfs_mknod,
 	.vop_open =			tmpfs_open,
@@ -1563,3 +1579,10 @@ struct vop_vector tmpfs_vnodeop_entries = {
 	.vop_vptocnp =			tmpfs_vptocnp,
 };
 
+/*
+ * Same vector for mounts which do not use namecache.
+ */
+struct vop_vector tmpfs_vnodeop_nonc_entries = {
+	.vop_default =			&tmpfs_vnodeop_entries,
+	.vop_lookup =			tmpfs_lookup,
+};
diff --git a/sys/fs/tmpfs/tmpfs_vnops.h b/sys/fs/tmpfs/tmpfs_vnops.h
index 1e06c13..db614a05 100644
--- a/sys/fs/tmpfs/tmpfs_vnops.h
+++ b/sys/fs/tmpfs/tmpfs_vnops.h
@@ -44,6 +44,7 @@
  */
 
 extern struct vop_vector tmpfs_vnodeop_entries;
+extern struct vop_vector tmpfs_vnodeop_nonc_entries;
 
 vop_access_t	tmpfs_access;
 vop_getattr_t	tmpfs_getattr;