From 33a2fa47c929f62fd1f2a3491ea06e5960507846 Mon Sep 17 00:00:00 2001
From: Giuseppe Scrivano <gscrivan@redhat.com>
Date: Wed, 11 Nov 2020 15:20:50 +0100
Subject: [PATCH] main: invalidate directory cache on create/rename

if we are adding a new file to a directory, the parent directory must
be invalidated if it is in the middle of a opendir/releasedir
otherwise the added files won't be cached.

Closes: https://github.com/containers/fuse-overlayfs/issues/259

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
---
 fuse-overlayfs.h |  1 +
 main.c           | 26 +++++++++++++++++++++++++-
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/fuse-overlayfs.h b/fuse-overlayfs.h
index 012aed1..f43dfc0 100644
--- a/fuse-overlayfs.h
+++ b/fuse-overlayfs.h
@@ -50,6 +50,7 @@ struct ovl_node
   Hash_table *inodes;
   struct ovl_ino *ino;
   struct ovl_node *next_link;
+  unsigned int in_readdir;
 
   unsigned int do_unlink : 1;
   unsigned int do_rmdir : 1;
diff --git a/main.c b/main.c
index a5a9f95..03f57c9 100644
--- a/main.c
+++ b/main.c
@@ -2183,6 +2183,7 @@ ovl_opendir (fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)
       fi->cache_readdir = 1;
 #endif
     }
+  node->in_readdir++;
   fuse_reply_open (req, fi);
   return;
 
@@ -2395,6 +2396,7 @@ ovl_releasedir (fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)
   size_t s;
   struct ovl_dirp *d = ovl_dirp (fi);
   struct ovl_data *lo = ovl_data (req);
+  struct ovl_node *node = NULL;
 
   if (UNLIKELY (ovl_debug (req)))
     fprintf (stderr, "ovl_releasedir(ino=%" PRIu64 ")\n", ino);
@@ -2409,6 +2411,10 @@ ovl_releasedir (fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)
         }
     }
 
+  node = do_lookup_file (lo, ino, NULL);
+  if (node)
+    node->in_readdir--;
+
   free (d->tbl);
   free (d);
   fuse_reply_err (req, 0);
@@ -3709,7 +3715,7 @@ ovl_create (fuse_req_t req, fuse_ino_t parent, const char *name,
   cleanup_lock int l = enter_big_lock ();
   cleanup_close int fd = -1;
   struct fuse_entry_param e;
-  struct ovl_node *node = NULL;
+  struct ovl_node *p, *node = NULL;
   struct ovl_data *lo = ovl_data (req);
   struct stat st;
 
@@ -3735,6 +3741,11 @@ ovl_create (fuse_req_t req, fuse_ino_t parent, const char *name,
       return;
     }
 
+  p = do_lookup_file (lo, parent, NULL);
+  /* Make sure the cache is invalidated, if the parent is in the middle of a readdir. */
+  if (p && p->in_readdir)
+    fuse_lowlevel_notify_inval_inode (lo->se, parent, 0, 0);
+
   if (node == NULL || do_getattr (req, &e, node, fd, NULL) < 0)
     {
       fuse_reply_err (req, errno);
@@ -4551,6 +4562,7 @@ ovl_rename (fuse_req_t req, fuse_ino_t parent, const char *name,
            fuse_ino_t newparent, const char *newname,
            unsigned int flags)
 {
+  struct ovl_node *p;
   cleanup_lock int l = enter_big_lock ();
   struct ovl_data *lo = ovl_data (req);
 
@@ -4567,6 +4579,14 @@ ovl_rename (fuse_req_t req, fuse_ino_t parent, const char *name,
     ovl_rename_exchange (req, parent, name, newparent, newname, flags);
   else
     ovl_rename_direct (req, parent, name, newparent, newname, flags);
+
+  /* Make sure the cache is invalidated, if the parent is in the middle of a readdir. */
+  p = do_lookup_file (lo, parent, NULL);
+  if (p && p->in_readdir)
+    fuse_lowlevel_notify_inval_inode (lo->se, parent, 0, 0);
+  p = do_lookup_file (lo, newparent, NULL);
+  if (p && p->in_readdir)
+    fuse_lowlevel_notify_inval_inode (lo->se, newparent, 0, 0);
 }
 
 static void
@@ -4785,6 +4805,10 @@ ovl_mknod (fuse_req_t req, fuse_ino_t parent, const char *name, mode_t mode, dev
       return;
     }
 
+  /* Make sure the cache is invalidated, if the parent is in the middle of a readdir. */
+  if (pnode->in_readdir)
+    fuse_lowlevel_notify_inval_inode (lo->se, parent, 0, 0);
+
   e.ino = node_to_inode (node);
   e.attr_timeout = get_timeout (lo);
   e.entry_timeout = get_timeout (lo);