From 296274b60f15ed7ca7e82bfe1251e443833c2727 Mon Sep 17 00:00:00 2001
From: chenwei <chenwei26@huawei.com>
Date: Sat, 17 Apr 2021 11:44:03 +0800
Subject: [PATCH] add debug code to fix bug: kernel crashed after rmdir the
 umounted folder, parent->data null

Change-Id: I44981eb9475feb4604ffe91244b4dff00f7d1548
---
 fs/jffs2/src/vfs_jffs2.c |  6 ++++++
 fs/vfs/vnode.c           | 15 ++++++++++-----
 2 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/fs/jffs2/src/vfs_jffs2.c b/fs/jffs2/src/vfs_jffs2.c
index 5f602d74..2f9448f0 100755
--- a/fs/jffs2/src/vfs_jffs2.c
+++ b/fs/jffs2/src/vfs_jffs2.c
@@ -593,6 +593,8 @@ int VfsJffs2Chattr(struct Vnode *pVnode, struct IATTR *attr)
     return ret;
 }
 
+extern struct Vnode *g_parentOfCoveredVnode;
+
 int VfsJffs2Rmdir(struct Vnode *parentVnode, struct Vnode *targetVnode, char *path)
 {
     int ret;
@@ -603,6 +605,10 @@ int VfsJffs2Rmdir(struct Vnode *parentVnode, struct Vnode *targetVnode, char *pa
 
     LOS_MuxLock(&g_jffs2FsLock, (uint32_t)JFFS2_WAITING_FOREVER);
 
+    if (parentVnode->data == NULL) {
+        PRINT_ERR("%s-%d: rmdir parent of mounted vnode. vnode=%p userCount=%d inode=%p\n", __FUNCTION__, __LINE__, parentVnode, parentVnode->useCount, parentVnode->data);
+        PRINT_ERR("%s-%d: global rmdir parent of mounted vnode. vnode=%p userCount=%d inode=%p\n", __FUNCTION__, __LINE__, g_parentOfCoveredVnode, g_parentOfCoveredVnode->useCount, g_parentOfCoveredVnode->data);
+    }
     ret = jffs2_rmdir((struct jffs2_inode *)parentVnode->data, (struct jffs2_inode *)targetVnode->data,
                       (const unsigned char *)path);
 
diff --git a/fs/vfs/vnode.c b/fs/vfs/vnode.c
index fc979fd9..99287d8d 100755
--- a/fs/vfs/vnode.c
+++ b/fs/vfs/vnode.c
@@ -92,6 +92,8 @@ static struct Vnode *GetFromFreeList(void)
     return vnode;
 }
 
+extern struct Vnode *g_parentOfCoveredVnode;
+
 struct Vnode *VnodeReclaimLru(void)
 {
     struct Vnode *item = NULL;
@@ -106,11 +108,6 @@ struct Vnode *VnodeReclaimLru(void)
         }
 
         if (VnodeFree(item) == LOS_OK) {
-            for (int i = 0; i < g_coveredVnodeTop; i++) {
-                if (item == g_coveredVnodeList[i]) {
-                    PRINT_ERR("%s-%d: reclaim mounted vnode. item=%p\n", __FUNCTION__, __LINE__, item);
-                }
-            }
             releaseCount++;
         }
         if (releaseCount >= VNODE_LRU_COUNT) {
@@ -180,6 +177,14 @@ int VnodeFree(struct Vnode *vnode)
     struct PathCache *nextItem = NULL;
 
     VnodeHold();
+    for (int i = 0; i < g_coveredVnodeTop; i++) {
+        if (vnode == g_coveredVnodeList[i]) {
+            PRINT_ERR("%s-%d: reclaim mounted vnode. vnode=%p userCount=%d inode=%p\n", __FUNCTION__, __LINE__, vnode, vnode->useCount, vnode->data);
+        }
+    }
+    if (g_parentOfCoveredVnode == vnode) {
+        PRINT_ERR("%s-%d: reclaim parent of mounted vnode. vnode=%p userCount=%d inode=%p\n", __FUNCTION__, __LINE__, vnode, vnode->useCount, vnode->data);
+    }
     if (vnode->useCount > 0) {
         VnodeDrop();
         return -EBUSY;