--- zzzz-none-000/linux-3.10.107/fs/autofs4/autofs_i.h	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/fs/autofs4/autofs_i.h	2021-02-04 17:41:59.000000000 +0000
@@ -79,6 +79,14 @@
 };
 
 #define AUTOFS_INF_EXPIRING	(1<<0) /* dentry is in the process of expiring */
+#define AUTOFS_INF_WANT_EXPIRE	(1<<1) /* the dentry is being considered
+					* for expiry, so RCU_walk is
+					* not permitted.  If it progresses to
+					* actual expiry attempt, the flag is
+					* not cleared when EXPIRING is set -
+					* in that case it gets cleared only
+					* when it comes to clearing EXPIRING.
+					*/
 #define AUTOFS_INF_PENDING	(1<<2) /* dentry pending mount */
 
 struct autofs_wait_queue {
@@ -104,7 +112,7 @@
 	u32 magic;
 	int pipefd;
 	struct file *pipe;
-	pid_t oz_pgrp;
+	struct pid *oz_pgrp;
 	int catatonic;
 	int version;
 	int sub_version;
@@ -122,6 +130,7 @@
 	spinlock_t lookup_lock;
 	struct list_head active_list;
 	struct list_head expiring_list;
+	struct rcu_head rcu;
 };
 
 static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb)
@@ -139,21 +148,7 @@
    filesystem without "magic".) */
 
 static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
-	return sbi->catatonic || task_pgrp_nr(current) == sbi->oz_pgrp;
-}
-
-/* Does a dentry have some pending activity? */
-static inline int autofs4_ispending(struct dentry *dentry)
-{
-	struct autofs_info *inf = autofs4_dentry_ino(dentry);
-
-	if (inf->flags & AUTOFS_INF_PENDING)
-		return 1;
-
-	if (inf->flags & AUTOFS_INF_EXPIRING)
-		return 1;
-
-	return 0;
+	return sbi->catatonic || task_pgrp(current) == sbi->oz_pgrp;
 }
 
 struct inode *autofs4_get_inode(struct super_block *, umode_t);
@@ -161,7 +156,7 @@
 
 /* Expiration */
 int is_autofs4_dentry(struct dentry *);
-int autofs4_expire_wait(struct dentry *dentry);
+int autofs4_expire_wait(struct dentry *dentry, int rcu_walk);
 int autofs4_expire_run(struct super_block *, struct vfsmount *,
 			struct autofs_sb_info *,
 			struct autofs_packet_expire __user *);
@@ -190,55 +185,6 @@
 extern const struct dentry_operations autofs4_dentry_operations;
 
 /* VFS automount flags management functions */
-
-static inline void __managed_dentry_set_automount(struct dentry *dentry)
-{
-	dentry->d_flags |= DCACHE_NEED_AUTOMOUNT;
-}
-
-static inline void managed_dentry_set_automount(struct dentry *dentry)
-{
-	spin_lock(&dentry->d_lock);
-	__managed_dentry_set_automount(dentry);
-	spin_unlock(&dentry->d_lock);
-}
-
-static inline void __managed_dentry_clear_automount(struct dentry *dentry)
-{
-	dentry->d_flags &= ~DCACHE_NEED_AUTOMOUNT;
-}
-
-static inline void managed_dentry_clear_automount(struct dentry *dentry)
-{
-	spin_lock(&dentry->d_lock);
-	__managed_dentry_clear_automount(dentry);
-	spin_unlock(&dentry->d_lock);
-}
-
-static inline void __managed_dentry_set_transit(struct dentry *dentry)
-{
-	dentry->d_flags |= DCACHE_MANAGE_TRANSIT;
-}
-
-static inline void managed_dentry_set_transit(struct dentry *dentry)
-{
-	spin_lock(&dentry->d_lock);
-	__managed_dentry_set_transit(dentry);
-	spin_unlock(&dentry->d_lock);
-}
-
-static inline void __managed_dentry_clear_transit(struct dentry *dentry)
-{
-	dentry->d_flags &= ~DCACHE_MANAGE_TRANSIT;
-}
-
-static inline void managed_dentry_clear_transit(struct dentry *dentry)
-{
-	spin_lock(&dentry->d_lock);
-	__managed_dentry_clear_transit(dentry);
-	spin_unlock(&dentry->d_lock);
-}
-
 static inline void __managed_dentry_set_managed(struct dentry *dentry)
 {
 	dentry->d_flags |= (DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT);
@@ -271,7 +217,7 @@
 
 static inline int autofs_prepare_pipe(struct file *pipe)
 {
-	if (!pipe->f_op || !pipe->f_op->write)
+	if (!(pipe->f_mode & FMODE_CAN_WRITE))
 		return -EINVAL;
 	if (!S_ISFIFO(file_inode(pipe)->i_mode))
 		return -EINVAL;
@@ -293,12 +239,7 @@
 
 static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi)
 {
-	return sbi->sb->s_root->d_inode->i_ino;
-}
-
-static inline int simple_positive(struct dentry *dentry)
-{
-	return dentry->d_inode && !d_unhashed(dentry);
+	return d_inode(sbi->sb->s_root)->i_ino;
 }
 
 static inline void __autofs4_add_expiring(struct dentry *dentry)