diff --git a/sys/fs/msdosfs/msdosfs_lookup.c b/sys/fs/msdosfs/msdosfs_lookup.c
--- a/sys/fs/msdosfs/msdosfs_lookup.c
+++ b/sys/fs/msdosfs/msdosfs_lookup.c
@@ -684,6 +684,7 @@
 		return error;
 	}
 	ndep = bptoep(pmp, bp, ddep->de_fndoffset);
+	rootde_alloced(ddep);
 
 	DE_EXTERNALIZE(ndep, dep);
 
@@ -721,6 +722,7 @@
 				ndep--;
 				ddep->de_fndoffset -= sizeof(struct direntry);
 			}
+			rootde_alloced(ddep);
 			if (!unix2winfn(un, unlen, (struct winentry *)ndep,
 					cnt++, chksum, pmp))
 				break;
@@ -1015,6 +1017,7 @@
 			 */
 			offset -= sizeof(struct direntry);
 			ep--->deName[0] = SLOT_DELETED;
+			rootde_freed(pdep);
 			if ((pmp->pm_flags & MSDOSFSMNT_NOWIN95)
 			    || !(offset & pmp->pm_crbomask)
 			    || ep->deAttributes != ATTR_WIN95)
diff --git a/sys/fs/msdosfs/msdosfs_vfsops.c b/sys/fs/msdosfs/msdosfs_vfsops.c
--- a/sys/fs/msdosfs/msdosfs_vfsops.c
+++ b/sys/fs/msdosfs/msdosfs_vfsops.c
@@ -409,6 +409,67 @@
 	return (0);
 }
 
+static int
+rootdir_free(struct msdosfsmount* pmp)
+{
+	struct buf *bp;
+	struct direntry *dep;
+	u_long readsize;
+	int dirclu;
+	int diridx;
+	int dirmax;
+	int dirleft;
+	int ffree;
+
+	dirclu = pmp->pm_firstcluster - pmp->pm_rootdirsize;
+	dirleft = pmp->pm_RootDirEnts;
+	readsize = MAXBCACHEBUF;
+
+#ifdef MSDOSFS_DEBUG
+	printf("rootdir_free: blkpersec=%lu fatblksize=%lu readsize=%lu firstclu=%lu dirclu=%lu rootdirsize=%lu\n",
+	    pmp->pm_BlkPerSec, pmp->pm_fatblocksize, readsize, pmp->pm_firstcluster, dirclu, pmp->pm_rootdirsize);
+#endif
+	ffree = pmp->pm_RootDirEnts;
+	while (dirleft > 0 && ffree > 0) {
+		if (readsize > dirleft * sizeof(struct direntry))
+			readsize = roundup(dirleft * sizeof(struct direntry), DEV_BSIZE);
+#ifdef MSDOSFS_DEBUG
+		printf("rootdir_free: dirclu=%lu readsize=%lu\n", dirclu, readsize);
+#endif
+		if (bread(pmp->pm_devvp, dirclu, readsize, NOCRED, &bp) != 0) {
+			dirleft = 0;
+			ffree = -1;
+			printf("rootdir_free: read error\n");
+		}
+		dirmax = readsize / sizeof(struct direntry);
+		for (diridx = 0; diridx < dirmax && dirleft > 0; diridx++, dirleft--) {
+			dep = (struct direntry*)bp->b_data + diridx;
+#ifdef MSDOSFS_DEBUG
+			if (dep->deName[0] == SLOT_DELETED)
+				printf("rootdir_free: idx=%d <deleted>\n", diridx);
+			else if (dep->deName[0] == SLOT_EMPTY)
+				printf("rootdir_free: idx=%d <end marker>\n", diridx);
+			else if (dep->deAttributes == ATTR_WIN95)
+				printf("rootdir_free: idx=%d <long file name>\n", diridx);
+			else if (dep->deAttributes & ATTR_VOLUME)
+				printf("rootdir_free: idx=%d label='%11.11s'\n", diridx, dep->deName);
+			else if (dep->deAttributes & ATTR_DIRECTORY)
+				printf("rootdir_free: idx=%d dir='%11.11s'\n", diridx, dep->deName);
+			else
+				printf("rootdir_free: idx=%d file='%11.11s'\n", diridx, dep->deName);
+#endif
+			if (dep->deName[0] == SLOT_EMPTY)
+				dirleft = 0;
+			else if (dep->deName[0] != SLOT_DELETED)
+				ffree--;
+		}
+		brelse(bp);
+		bp = NULL;
+		dirclu += readsize / DEV_BSIZE;
+	}
+	return (ffree);
+}
+
 static int
 mountmsdosfs(struct vnode *odevvp, struct mount *mp)
 {
@@ -747,6 +808,15 @@
 			goto error_exit;
 		pmp->pm_fmod = 1;
 	}
+
+	if (FAT32(pmp)) {
+		pmp->pm_rootdirfree = 0;
+	} else {
+		pmp->pm_rootdirfree = rootdir_free(pmp);
+		if (pmp->pm_rootdirfree < 0)
+			goto error_exit;
+	}
+
 	mp->mnt_data =  pmp;
 	mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
 	mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
@@ -948,8 +1018,8 @@
 	sbp->f_blocks = pmp->pm_maxcluster + 1;
 	sbp->f_bfree = pmp->pm_freeclustercount;
 	sbp->f_bavail = pmp->pm_freeclustercount;
-	sbp->f_files = pmp->pm_RootDirEnts;	/* XXX */
-	sbp->f_ffree = 0;	/* what to put in here? */
+	sbp->f_files = pmp->pm_RootDirEnts;
+	sbp->f_ffree = pmp->pm_rootdirfree;
 	return (0);
 }
 
diff --git a/sys/fs/msdosfs/msdosfsmount.h b/sys/fs/msdosfs/msdosfsmount.h
--- a/sys/fs/msdosfs/msdosfsmount.h
+++ b/sys/fs/msdosfs/msdosfsmount.h
@@ -114,6 +114,7 @@
 	void *pm_w2u;	/* Unicode->Local iconv handle */
 	void *pm_u2d;	/* Unicode->DOS iconv handle */
 	void *pm_d2u;	/* DOS->Local iconv handle */
+	u_short pm_rootdirfree;	/* number of free slots in FAT12/16 root directory */
 #ifndef MAKEFS
 	struct lock pm_fatlock;	/* lockmgr protecting allocations */
 	struct lock pm_checkpath_lock; /* protects doscheckpath result */
@@ -222,6 +223,22 @@
 	 ? roottobn((pmp), (dirofs)) \
 	 : cntobn((pmp), (dirclu)))
 
+/*
+ * Decrement the number of used entries in a fixed size FAT12/16 root
+ * directory
+ */
+#define rootde_alloced(dep) \
+	if ((dep)->de_StartCluster == MSDOSFSROOT) \
+		(dep)->de_pmp->pm_rootdirfree--;
+
+/*
+ * Increment the number of used entries in a fixed size FAT12/16 root
+ * directory
+ */
+#define rootde_freed(dep) \
+	if ((dep)->de_StartCluster == MSDOSFSROOT) \
+		(dep)->de_pmp->pm_rootdirfree++;
+
 #define	MSDOSFS_LOCK_MP(pmp) \
 	lockmgr(&(pmp)->pm_fatlock, LK_EXCLUSIVE, NULL)
 #define	MSDOSFS_UNLOCK_MP(pmp) \