From: Matthew Dillon <dillon@apollo.backplane.com>
Date: Sat, 20 Feb 2010 03:07:43 +0000 (-0800)
Subject: kernel - TMPFS - Stabilization pass, fix VM object leak, msync
X-Git-Tag: v2.7.0~166
X-Git-Url: https://gitweb.dragonflybsd.org/~nant/dragonfly.git/commitdiff_plain/f96f2f39b0082a3241919be617757c2235a6add0

kernel - TMPFS - Stabilization pass, fix VM object leak, msync

* The swap vm_object backing regular files was not being deallocated
  properly and leaked kernel memory.

* Truncate deleted files a little earlier in the INACTIVE path.

* Set MNTK_NOMSYNC.  This prevents msync(), sync(), and the
  periodic filesystem syncer from flushing pages to swap.

  VM pages related to tmpfs are only flushed based on memory
  pressure.
---

diff --git a/sys/vfs/tmpfs/tmpfs_subr.c b/sys/vfs/tmpfs/tmpfs_subr.c
index 3a666b0626..9c928a6d5c 100644
--- a/sys/vfs/tmpfs/tmpfs_subr.c
+++ b/sys/vfs/tmpfs/tmpfs_subr.c
@@ -276,7 +276,7 @@ tmpfs_free_node(struct tmpfs_mount *tmp, struct tmpfs_node *node)
 
 	case VREG:
 		if (node->tn_reg.tn_aobj != NULL)
-			vm_pager_deallocate(node->tn_reg.tn_aobj);
+			vm_object_deallocate(node->tn_reg.tn_aobj);
 		node->tn_reg.tn_aobj = NULL;
 		pages = node->tn_reg.tn_aobj_pages;
 		break;
diff --git a/sys/vfs/tmpfs/tmpfs_vfsops.c b/sys/vfs/tmpfs/tmpfs_vfsops.c
index 074d34d22c..b63c34985f 100644
--- a/sys/vfs/tmpfs/tmpfs_vfsops.c
+++ b/sys/vfs/tmpfs/tmpfs_vfsops.c
@@ -245,6 +245,7 @@ tmpfs_mount(struct mount *mp, char *path, caddr_t data, struct ucred *cred)
 	mp->mnt_kern_flag |= MNTK_RD_MPSAFE | MNTK_WR_MPSAFE | MNTK_GA_MPSAFE  |
 			     MNTK_IN_MPSAFE | MNTK_SG_MPSAFE;
 #endif
+	mp->mnt_kern_flag |= MNTK_NOMSYNC;
 	mp->mnt_data = (qaddr_t)tmp;
 	vfs_getnewfsid(mp);
 
diff --git a/sys/vfs/tmpfs/tmpfs_vnops.c b/sys/vfs/tmpfs/tmpfs_vnops.c
index 42e39d409a..e8ba5b1490 100644
--- a/sys/vfs/tmpfs/tmpfs_vnops.c
+++ b/sys/vfs/tmpfs/tmpfs_vnops.c
@@ -1319,6 +1319,9 @@ tmpfs_inactive(struct vop_inactive_args *v)
 	/*
 	 * Get rid of unreferenced deleted vnodes sooner rather than
 	 * later so the data memory can be recovered immediately.
+	 *
+	 * We must truncate the vnode to prevent the normal reclamation
+	 * path from flushing the data for the removed file to disk.
 	 */
 	TMPFS_NODE_LOCK(node);
 	if ((node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0 &&
@@ -1328,6 +1331,8 @@ tmpfs_inactive(struct vop_inactive_args *v)
 	{
 		node->tn_vpstate = TMPFS_VNODE_DOOMED;
 		TMPFS_NODE_UNLOCK(node);
+		if (node->tn_type == VREG)
+			tmpfs_truncate(vp, 0);
 		vrecycle(vp);
 	} else {
 		TMPFS_NODE_UNLOCK(node);