[Devel] [PATCH RHEL7 COMMIT] Revert "ms/ovl: update atime on upperovl: update atime on upper"

[Konstantin Khorenko]

The commit is pushed to "branch-rh7-3.10.0-327.28.2.vz7.17.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh7-3.10.0-327.28.2.vz7.17.8
------>
commit d3dc167710ea15dbbd77bb88f3d10d51e4600789
Author: Konstantin Khorenko <khorenko at virtuozzo.com>
Date:   Wed Sep 21 17:53:09 2016 +0400

    Revert "ms/ovl: update atime on upperovl: update atime on upper"
    
    Temporary revert due to panic:
    https://jira.sw.ru/browse/PSBM-52373
    
    This reverts commit 72814686c2596add559bba25d551af93193b0287.
---
 fs/overlayfs/dir.c       |  1 -
 fs/overlayfs/inode.c     | 29 +++--------------------------
 fs/overlayfs/overlayfs.h |  4 ----
 fs/overlayfs/super.c     |  8 ++------
 4 files changed, 5 insertions(+), 37 deletions(-)

diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index 881987c..5402b9b 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -966,7 +966,6 @@ const struct inode_operations_wrapper ovl_dir_inode_operations = {
 	.getxattr	= ovl_getxattr,
 	.listxattr	= ovl_listxattr,
 	.removexattr	= ovl_removexattr,
-	.update_time	= ovl_update_time,
 	},
 	.rename2	= ovl_rename2,
 };
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 77f2da4..5fe7acf 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -196,6 +196,8 @@ static int ovl_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
 	if (!realinode->i_op->readlink)
 		return -EINVAL;
 
+	touch_atime(&realpath);
+
 	return realinode->i_op->readlink(realpath.dentry, buf, bufsiz);
 }
 
@@ -381,29 +383,6 @@ struct inode *ovl_d_select_inode(struct dentry *dentry)
 	return d_backing_inode(realpath.dentry);
 }
 
-int ovl_update_time(struct inode *inode, struct timespec *ts, int flags)
-{
-	struct dentry *alias;
-	struct path upperpath;
-
-	if (!(flags & S_ATIME))
-		return 0;
-
-	alias = d_find_any_alias(inode);
-	if (!alias)
-		return 0;
-
-	ovl_path_upper(alias, &upperpath);
-	if (upperpath.dentry) {
-		touch_atime(&upperpath);
-		inode->i_atime = d_inode(upperpath.dentry)->i_atime;
-	}
-
-	dput(alias);
-
-	return 0;
-}
-
 static const struct inode_operations_wrapper ovl_file_inode_operations = {
 	.ops = {
 	.setattr	= ovl_setattr,
@@ -413,7 +392,6 @@ static const struct inode_operations_wrapper ovl_file_inode_operations = {
 	.getxattr	= ovl_getxattr,
 	.listxattr	= ovl_listxattr,
 	.removexattr	= ovl_removexattr,
-	.update_time	= ovl_update_time,
 	},
 	.dentry_open	= ovl_dentry_open,
 };
@@ -428,7 +406,6 @@ static const struct inode_operations ovl_symlink_inode_operations = {
 	.getxattr	= ovl_getxattr,
 	.listxattr	= ovl_listxattr,
 	.removexattr	= ovl_removexattr,
-	.update_time	= ovl_update_time,
 };
 
 struct inode *ovl_new_inode(struct super_block *sb, umode_t mode,
@@ -444,7 +421,7 @@ struct inode *ovl_new_inode(struct super_block *sb, umode_t mode,
 
 	inode->i_ino = get_next_ino();
 	inode->i_mode = mode;
-	inode->i_flags |= S_NOCMTIME;
+	inode->i_flags |= S_NOATIME | S_NOCMTIME;
 
 	switch (mode) {
 	case S_IFDIR:
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 61ba0d5..8da9684 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -174,7 +174,6 @@ ssize_t ovl_getxattr(struct dentry *dentry, const char *name,
 ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size);
 int ovl_removexattr(struct dentry *dentry, const char *name);
 struct inode *ovl_d_select_inode(struct dentry *dentry);
-int ovl_update_time(struct inode *inode, struct timespec *ts, int flags);
 
 struct inode *ovl_new_inode(struct super_block *sb, umode_t mode,
 			    struct ovl_entry *oe);
@@ -182,9 +181,6 @@ static inline void ovl_copyattr(struct inode *from, struct inode *to)
 {
 	to->i_uid = from->i_uid;
 	to->i_gid = from->i_gid;
-	to->i_atime = from->i_atime;
-	to->i_mtime = from->i_mtime;
-	to->i_ctime = from->i_ctime;
 }
 
 /* dir.c */
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index b46463a..2935967 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -533,7 +533,7 @@ out:
 
 struct file *ovl_path_open(struct path *path, int flags)
 {
-	return dentry_open(path, flags | O_NOATIME, current_cred());
+	return dentry_open(path, flags, current_cred());
 }
 
 static void ovl_put_super(struct super_block *sb)
@@ -1013,10 +1013,6 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
 			pr_err("overlayfs: failed to clone upperpath\n");
 			goto out_put_lowerpath;
 		}
-		/* Don't inherit atime flags */
-		ufs->upper_mnt->mnt_flags &= ~(MNT_NOATIME | MNT_NODIRATIME | MNT_RELATIME);
-
-		sb->s_time_gran = ufs->upper_mnt->mnt_sb->s_time_gran;
 
 		ufs->workdir = ovl_workdir_create(ufs->upper_mnt, workpath.dentry);
 		err = PTR_ERR(ufs->workdir);
@@ -1044,7 +1040,7 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
 		 * Make lower_mnt R/O.  That way fchmod/fchown on lower file
 		 * will fail instead of modifying lower fs.
 		 */
-		mnt->mnt_flags |= MNT_READONLY | MNT_NOATIME;
+		mnt->mnt_flags |= MNT_READONLY;
 
 		ufs->lower_mnt[ufs->numlower] = mnt;
 		ufs->numlower++;