[PATCH 2/2] scripts/gdb: Add GDB convenience functions $lx_dentry_name() and $lx_i_dentry()

[Glenn Washburn]

$lx_dentry_name() generates a full VFS path from a given dentry pointer,
and $lx_i_dentry() returns the dentry pointer associated with the given
inode pointer, if there is one.

Signed-off-by: Glenn Washburn <development@xxxxxxxxxxxxxxx>
---
 scripts/gdb/linux/vfs.py | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/scripts/gdb/linux/vfs.py b/scripts/gdb/linux/vfs.py
index 62d4f9ad7d79..c77b9ce75f6d 100644
--- a/scripts/gdb/linux/vfs.py
+++ b/scripts/gdb/linux/vfs.py
@@ -13,6 +13,9 @@
 # This work is licensed under the terms of the GNU GPL version 2.
 #
 
+import gdb
+from linux import utils
+
 
 def dentry_name(d):
     parent = d['d_parent']
@@ -20,3 +23,37 @@ def dentry_name(d):
         return ""
     p = dentry_name(d['d_parent']) + "/"
     return p + d['d_iname'].string()
+
+class DentryName(gdb.Function):
+    """Return string of the full path of a dentry.
+
+$lx_dentry_name(PTR): Given PTR to a dentry struct, return a string
+of the full path of the dentry."""
+
+    def __init__(self):
+        super(DentryName, self).__init__("lx_dentry_name")
+
+    def invoke(self, dentry_ptr):
+        return dentry_name(dentry_ptr)
+
+DentryName()
+
+
+dentry_type = utils.CachedType("struct dentry")
+
+class InodeDentry(gdb.Function):
+    """Return dentry pointer for inode.
+
+$lx_i_dentry(PTR): Given PTR to an inode struct, return a pointer to
+the associated dentry struct, if there is one."""
+
+    def __init__(self):
+        super(InodeDentry, self).__init__("lx_i_dentry")
+
+    def invoke(self, inode_ptr):
+        d_u = inode_ptr["i_dentry"]["first"]
+        if d_u == 0:
+            return ""
+        return utils.container_of(d_u, dentry_type.get_type().pointer(), "d_u")
+
+InodeDentry()
-- 
2.30.2