Unionfs: add lower nameidata debugging support

Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>

diff --git a/fs/unionfs/debug.c b/fs/unionfs/debug.c
index 2d15fb0fb869b7b130b90dd8d7ca0154fc41bb52..9546a4122cb9af77f03d2b4466f7bfeb2598906c 100644 (file)
--- a/fs/unionfs/debug.c
+++ b/fs/unionfs/debug.c
@@ -415,6 +415,26 @@ void __unionfs_check_file(const struct file *file,
        __unionfs_check_dentry(dentry,fname,fxn,line);
 }
 
+void __unionfs_check_nd(const struct nameidata *nd,
+                       const char *fname, const char *fxn, int line)
+{
+       struct file *file;
+       int printed_caller = 0;
+
+       if (!nd)
+               return;
+       if (nd->flags & LOOKUP_OPEN) {
+               file = nd->intent.open.file;
+               if (file->f_path.dentry &&
+                   strcmp(file->f_dentry->d_sb->s_type->name, "unionfs")) {
+                       PRINT_CALLER(fname, fxn, line);
+                       printk(" CND1: lower_file of type %s\n",
+                              file->f_path.dentry->d_sb->s_type->name);
+                       BUG();
+               }
+       }
+}
+
 /* useful to track vfsmount leaks that could cause EBUSY on unmount */
 void __show_branch_counts(const struct super_block *sb,
                          const char *file, const char *fxn, int line)

diff --git a/fs/unionfs/dentry.c b/fs/unionfs/dentry.c
index d9bb199617232e768ccd7db203f67f7959a1c677..b21f1e37218f4c1a2428efbedf79daa88eb46507 100644 (file)
--- a/fs/unionfs/dentry.c
+++ b/fs/unionfs/dentry.c
@@ -418,8 +418,10 @@ static int unionfs_d_revalidate(struct dentry *dentry, struct nameidata *nd)
        unionfs_lock_dentry(dentry);
        err = __unionfs_d_revalidate_chain(dentry, nd, false);
        unionfs_unlock_dentry(dentry);
-       if (err > 0) /* true==1: dentry is valid */
+       if (err > 0) { /* true==1: dentry is valid */
                unionfs_check_dentry(dentry);
+               unionfs_check_nd(nd);
+       }
 
        unionfs_read_unlock(dentry->d_sb);
 

diff --git a/fs/unionfs/inode.c b/fs/unionfs/inode.c
index de78e269a78a41297f07bc54f0942fac1e631b04..f8b2c88ccd234255db4492914b6bd6e215a9e455 100644 (file)
--- a/fs/unionfs/inode.c
+++ b/fs/unionfs/inode.c
@@ -138,8 +138,10 @@ out:
        unionfs_read_unlock(dentry->d_sb);
 
        unionfs_check_inode(parent);
-       if (!err)
+       if (!err) {
                unionfs_check_dentry(dentry->d_parent);
+               unionfs_check_nd(nd);
+       }
        unionfs_check_dentry(dentry);
        return err;
 }
@@ -186,6 +188,7 @@ static struct dentry *unionfs_lookup(struct inode *parent,
        unionfs_check_inode(parent);
        unionfs_check_dentry(dentry);
        unionfs_check_dentry(dentry->d_parent);
+       unionfs_check_nd(nd);
        unionfs_read_unlock(dentry->d_sb);
 
        return ret;
@@ -856,6 +859,7 @@ static void *unionfs_follow_link(struct dentry *dentry, struct nameidata *nd)
 
 out:
        unionfs_check_dentry(dentry);
+       unionfs_check_nd(nd);
        unionfs_read_unlock(dentry->d_sb);
        return ERR_PTR(err);
 }
@@ -872,6 +876,7 @@ static void unionfs_put_link(struct dentry *dentry, struct nameidata *nd,
        unionfs_unlock_dentry(dentry);
 
        unionfs_check_dentry(dentry);
+       unionfs_check_nd(nd);
        kfree(nd_get_link(nd));
        unionfs_read_unlock(dentry->d_sb);
 }
@@ -1002,6 +1007,7 @@ static int unionfs_permission(struct inode *inode, int mask,
 
 out:
        unionfs_check_inode(inode);
+       unionfs_check_nd(nd);
        return err;
 }
 

diff --git a/fs/unionfs/union.h b/fs/unionfs/union.h
index 178bdfc5445476f04a5fae3c2149b033e7095e44..870fe563a26087c2aee5983facd4dc8c443b7d00 100644 (file)
--- a/fs/unionfs/union.h
+++ b/fs/unionfs/union.h
@@ -522,6 +522,8 @@ static inline void unionfs_mntput(struct dentry *dentry, int bindex)
        __FILE__,__FUNCTION__,__LINE__)
 #define unionfs_check_file(f)  __unionfs_check_file((f),       \
        __FILE__,__FUNCTION__,__LINE__)
+#define unionfs_check_nd(n)    __unionfs_check_nd((n),         \
+       __FILE__,__FUNCTION__,__LINE__)
 #define show_branch_counts(sb) __show_branch_counts((sb),      \
        __FILE__,__FUNCTION__,__LINE__)
 #define show_inode_times(i)    __show_inode_times((i),         \
@@ -538,6 +540,8 @@ extern void __unionfs_check_dentry(const struct dentry *dentry,
                                   int line);
 extern void __unionfs_check_file(const struct file *file,
                                 const char *fname, const char *fxn, int line);
+extern void __unionfs_check_nd(const struct nameidata *nd,
+                              const char *fname, const char *fxn, int line);
 extern void __show_branch_counts(const struct super_block *sb,
                                 const char *file, const char *fxn, int line);
 extern void __show_inode_times(const struct inode *inode,