From dd19ef9dd01ac11230e2846f54c683618a0019ce Mon Sep 17 00:00:00 2001
From: Steven Whitehouse <swhiteho@fedoraproject.org>
Date: Wed, 26 Sep 2001 09:26:10 +0000
Subject: [PATCH]  o More updates

---
 driver/device-mapper/dmfs-root.c  | 39 ++------------
 driver/device-mapper/dmfs-super.c |  2 +
 driver/device-mapper/dmfs-tdir.c  | 86 +++++++++++++++++++++++++++++++
 3 files changed, 92 insertions(+), 35 deletions(-)

diff --git a/driver/device-mapper/dmfs-root.c b/driver/device-mapper/dmfs-root.c
index dab0c141e..7fd7e94db 100644
--- a/driver/device-mapper/dmfs-root.c
+++ b/driver/device-mapper/dmfs-root.c
@@ -47,6 +47,9 @@ static int dmfs_root_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 	if (!is_identifier(name, dentry->d_name.len))
 		return -EPERM;
 
+	if (dentry->d_name[0] == '.')
+		return -EINVAL;
+
 	inode = dmfs_create_lv(dir, dentry, mode);
 	if (!IS_ERR(inode)) {
 		md = dm_create(name, -1);
@@ -70,8 +73,7 @@ static int dmfs_root_mkdir(struct inode *dir, struct dentry *dentry, int mode)
  */
 static inline positive(struct dentry *dentry)
 {
-	return dentry->d_inode && dentry->d_inode->u.generic_ip &&
-	       !d_unhashed(dentry);
+	return dentry->d_inode && !d_unhashed(dentry);
 }
 
 static int empty(struct dentry *dentry)
@@ -94,45 +96,12 @@ static int empty(struct dentry *dentry)
 	return 1;
 }
 
-static int dmfs_delete_virtual(struct inode *dir, struct dentry *dentry)
-{
-	struct list_head *list;
-	struct dentry *de;
-	int rv = 0;
-
-	while(1) {
-		spin_lock(&dcache_lock);
-		list = dentry->d_subdirs.next;
-		if (list == &dentry->d_subdirs) {
-			spin_unlock(&dcache_lock);
-			break;
-		}
-		de = list_entry(list, struct dentry, d_child);
-		if (de->d_inode && !d_unhashed(de)) {
-			spin_unlock(&dcache_lock);
-			if (de->d_inode->u.generic_ip)
-				BUG();
-			rv = de->d_inode->ops->unlink(dir, de);
-			if (rv == 0) {
-				d_delete(de);
-				continue;
-			}
-			break;
-		}
-		spin_unlock(&dcache_lock);
-	}
-
-	return rv;
-}
-
 static int dmfs_root_rmdir(struct inode *dir, struct dentry *dentry)
 {
 	int ret = -ENOTEMPTY;
 
 	if (empty(dentry)) {
 		struct inode *inode = dentry->d_inode;
-
-		ret = dmfs_delete_virtual(dir, dentry);
 		if (ret == 0) {
 			inode->i_nlink--;
 			dput(dentry);
diff --git a/driver/device-mapper/dmfs-super.c b/driver/device-mapper/dmfs-super.c
index a1c06d7ae..fb9233a72 100644
--- a/driver/device-mapper/dmfs-super.c
+++ b/driver/device-mapper/dmfs-super.c
@@ -24,6 +24,8 @@
 
 #define DMFS_MAGIC 0x444D4653
 
+extern struct inode *dmfs_create_root(struct super_block *sb, int);
+
 static int dmfs_statfs(struct super_block *sb, struct statfs *buf)
 {
 	buf->f_type = sb->s_magic;
diff --git a/driver/device-mapper/dmfs-tdir.c b/driver/device-mapper/dmfs-tdir.c
index 04bd52971..971362bd7 100644
--- a/driver/device-mapper/dmfs-tdir.c
+++ b/driver/device-mapper/dmfs-tdir.c
@@ -28,6 +28,92 @@ extern struct inode *dmfs_create_error(struct inode *, int);
 extern struct inode *dmfs_create_table(struct inode *, int);
 extern struct inode *dmfs_create_status(struct inode *, int);
 
+
+static inline positive(struct dentry *dentry)
+{
+	return dentry->d_inode && !d_unhashed(dentry);
+}
+
+static int dm_deny_write_access(struct dentry *dentry)
+{
+	struct file file { f_dentry: &dentry };
+
+	return deny_write_access(&file);
+}
+
+static void dm_allow_dentry_list(struct dentry *list[], int i)
+{
+	int x;
+	for(x = 0; x < i; x++)
+		atomic_inc(&list[x]->d_inode->i_writecount);
+}
+
+static int dm_deny_dentry_list(struct dentry *list[], int i)
+{
+	int x;
+	int rv;
+
+	for(x = 0; x < i; x++) {
+		rv = dm_deny_write_access(list[x]);
+		if (rv)
+			goto error:
+	}
+	return 0;
+error:
+	if (x > 0) {
+		dm_allow_dentry_list(list, x - 1);
+	}
+	return rv;
+}
+
+static int dm_child_list(struct dentry *de_list[], struct dentry *dentry)
+{
+	struct list_head *list;
+	int i = 0;
+	int rv;
+
+	spin_lock(&dcache_lock);
+	list = dentry->d_subdirs.next;
+
+	while(list != &dentry->d_subdirs) {
+		struct dentry *de = list_entry(list, struct dentry, d_child);
+
+		if (positive(de))
+			de_list[i++] = dget(de);
+		list = list->next;
+	}
+	spin_unlock(&dcache_lock);
+
+	return i;
+}
+
+int dm_lock_tdir(struct dentry *dentry)
+{
+	struct dentry de_list[4];
+	int n, rv;
+
+	rv = n = dm_child_list(de_list, dentry);
+	if (n) {
+		rv = deny_dentry_list(de_list, n);
+		dput_list(de_list, n);
+	}
+
+	return rv;
+}
+
+int dm_unlock_tdir(struct dentry *dentry)
+{
+	struct dentry de_list[4];
+
+	rv = dm_child_list(de_list, dentry);
+	if (rv) {
+		dm_allow_dentry_list(de_list, rv);
+		dput_list(de_list, rv);
+	}
+
+	return rv;
+}
+
 static int dmfs_tdir_unlink(struct inode *dir, struct dentry *dentry)
 {
 	inode->i_nlink--;
-- 
2.43.5