[RFC PATCH 25/35] Revert "vfs: update ovl inode before relatime check"

From: Miklos Szeredi
Date: Thu Apr 12 2018 - 11:11:09 EST


This reverts commit 598e3c8f72f5b77c84d2cb26cfd936ffb3cfdbaa.

Overlayfs no longer relies on the vfs correct atime handling.

Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
---
fs/inode.c | 33 ++++++---------------------------
fs/internal.h | 7 -------
fs/namei.c | 2 +-
include/linux/fs.h | 1 +
4 files changed, 8 insertions(+), 35 deletions(-)

diff --git a/fs/inode.c b/fs/inode.c
index 163715de8cb2..4832a2b47f65 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1564,37 +1564,17 @@ sector_t bmap(struct inode *inode, sector_t block)
}
EXPORT_SYMBOL(bmap);

-/*
- * Update times in overlayed inode from underlying real inode
- */
-static void update_ovl_inode_times(struct dentry *dentry, struct inode *inode,
- bool rcu)
-{
- if (!rcu) {
- struct inode *realinode = d_real_inode(dentry);
-
- if (unlikely(inode != realinode) &&
- (!timespec_equal(&inode->i_mtime, &realinode->i_mtime) ||
- !timespec_equal(&inode->i_ctime, &realinode->i_ctime))) {
- inode->i_mtime = realinode->i_mtime;
- inode->i_ctime = realinode->i_ctime;
- }
- }
-}
-
/*
* With relative atime, only update atime if the previous atime is
* earlier than either the ctime or mtime or if at least a day has
* passed since the last atime update.
*/
-static int relatime_need_update(const struct path *path, struct inode *inode,
- struct timespec now, bool rcu)
+static int relatime_need_update(struct vfsmount *mnt, struct inode *inode,
+ struct timespec now)
{

- if (!(path->mnt->mnt_flags & MNT_RELATIME))
+ if (!(mnt->mnt_flags & MNT_RELATIME))
return 1;
-
- update_ovl_inode_times(path->dentry, inode, rcu);
/*
* Is mtime younger than atime? If yes, update atime:
*/
@@ -1665,8 +1645,7 @@ static int update_time(struct inode *inode, struct timespec *time, int flags)
* This function automatically handles read only file systems and media,
* as well as the "noatime" flag and inode specific "noatime" markers.
*/
-bool __atime_needs_update(const struct path *path, struct inode *inode,
- bool rcu)
+bool atime_needs_update(const struct path *path, struct inode *inode)
{
struct vfsmount *mnt = path->mnt;
struct timespec now;
@@ -1692,7 +1671,7 @@ bool __atime_needs_update(const struct path *path, struct inode *inode,

now = current_time(inode);

- if (!relatime_need_update(path, inode, now, rcu))
+ if (!relatime_need_update(mnt, inode, now))
return false;

if (timespec_equal(&inode->i_atime, &now))
@@ -1707,7 +1686,7 @@ void touch_atime(const struct path *path)
struct inode *inode = d_inode(path->dentry);
struct timespec now;

- if (!__atime_needs_update(path, inode, false))
+ if (!atime_needs_update(path, inode))
return;

if (!sb_start_write_trylock(inode->i_sb))
diff --git a/fs/internal.h b/fs/internal.h
index d5108d9c6a2f..f0eaa33890d9 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -127,13 +127,6 @@ extern long prune_icache_sb(struct super_block *sb, struct shrink_control *sc);
extern void inode_add_lru(struct inode *inode);
extern int dentry_needs_remove_privs(struct dentry *dentry);

-extern bool __atime_needs_update(const struct path *, struct inode *, bool);
-static inline bool atime_needs_update_rcu(const struct path *path,
- struct inode *inode)
-{
- return __atime_needs_update(path, inode, true);
-}
-
/*
* fs-writeback.c
*/
diff --git a/fs/namei.c b/fs/namei.c
index cafa365eeb70..2b3931bf5fb4 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1009,7 +1009,7 @@ const char *get_link(struct nameidata *nd)
if (!(nd->flags & LOOKUP_RCU)) {
touch_atime(&last->link);
cond_resched();
- } else if (atime_needs_update_rcu(&last->link, inode)) {
+ } else if (atime_needs_update(&last->link, inode)) {
if (unlikely(unlazy_walk(nd)))
return ERR_PTR(-ECHILD);
touch_atime(&last->link);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index e28a2cf50fa7..5e5dd484937f 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2062,6 +2062,7 @@ enum file_time_flags {
S_VERSION = 8,
};

+extern bool atime_needs_update(const struct path *, struct inode *);
extern void touch_atime(const struct path *);
static inline void file_accessed(struct file *file)
{
--
2.14.3