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ovl: opaque cleanup

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oe->opaque is set for

 a) whiteouts
 b) directories having the "trusted.overlay.opaque" xattr

Case b can be simplified, since setting the xattr always implies setting
oe->opaque.  Also once set, the opaque flag is never cleared.

Don't need to set opaque flag for non-directories.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This commit is contained in:
Miklos Szeredi 2016-12-16 11:02:57 +01:00
parent c5bef3a72b
commit 5cf5b477f0
4 changed files with 25 additions and 31 deletions
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6
fs/overlayfs/copy_up.c
View file

@ -303,12 +303,6 @@ static int ovl_copy_up_locked(struct dentry *workdir, struct dentry *upperdir,
ovl_dentry_update(dentry, newdentry);
ovl_inode_update(d_inode(dentry), d_inode(newdentry));
newdentry = NULL;
/*
* Non-directores become opaque when copied up.
*/
if (!S_ISDIR(stat->mode))
ovl_dentry_set_opaque(dentry, true);
out2:
dput(upper);
out1:

43
fs/overlayfs/dir.c
View file

@ -128,9 +128,15 @@ int ovl_create_real(struct inode *dir, struct dentry *newdentry,
return err;
}
static int ovl_set_opaque(struct dentry *upperdentry)
static int ovl_set_opaque(struct dentry *dentry, struct dentry *upperdentry)
{
return ovl_do_setxattr(upperdentry, OVL_XATTR_OPAQUE, "y", 1, 0);
int err;
err = ovl_do_setxattr(upperdentry, OVL_XATTR_OPAQUE, "y", 1, 0);
if (!err)
ovl_dentry_set_opaque(dentry);
return err;
}
static int ovl_dir_getattr(struct vfsmount *mnt, struct dentry *dentry,
@ -274,7 +280,7 @@ static struct dentry *ovl_clear_empty(struct dentry *dentry,
if (err)
goto out_cleanup;
err = ovl_set_opaque(opaquedir);
err = ovl_set_opaque(dentry, opaquedir);
if (err)
goto out_cleanup;
@ -435,7 +441,7 @@ static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
}
if (!hardlink && S_ISDIR(stat->mode)) {
err = ovl_set_opaque(newdentry);
err = ovl_set_opaque(dentry, newdentry);
if (err)
goto out_cleanup;
@ -996,29 +1002,22 @@ static int ovl_rename(struct inode *olddir, struct dentry *old,
if (WARN_ON(olddentry->d_inode == newdentry->d_inode))
goto out_dput;
err = 0;
if (is_dir) {
if (ovl_type_merge_or_lower(old)) {
if (ovl_type_merge_or_lower(old))
err = ovl_set_redirect(old, samedir);
if (err)
goto out_dput;
} else if (!old_opaque && ovl_lower_positive(new)) {
err = ovl_set_opaque(olddentry);
if (err)
goto out_dput;
ovl_dentry_set_opaque(old, true);
}
else if (!old_opaque && ovl_lower_positive(new))
err = ovl_set_opaque(old, olddentry);
if (err)
goto out_dput;
}
if (!overwrite && new_is_dir) {
if (ovl_type_merge_or_lower(new)) {
if (ovl_type_merge_or_lower(new))
err = ovl_set_redirect(new, samedir);
if (err)
goto out_dput;
} else if (!new_opaque && ovl_lower_positive(old)) {
err = ovl_set_opaque(newdentry);
if (err)
goto out_dput;
ovl_dentry_set_opaque(new, true);
}
else if (!new_opaque && ovl_lower_positive(old))
err = ovl_set_opaque(new, newdentry);
if (err)
goto out_dput;
}
err = ovl_do_rename(old_upperdir->d_inode, olddentry,

2
fs/overlayfs/overlayfs.h
View file

@ -156,7 +156,7 @@ struct ovl_dir_cache *ovl_dir_cache(struct dentry *dentry);
void ovl_set_dir_cache(struct dentry *dentry, struct ovl_dir_cache *cache);
bool ovl_dentry_is_opaque(struct dentry *dentry);
bool ovl_dentry_is_whiteout(struct dentry *dentry);
void ovl_dentry_set_opaque(struct dentry *dentry, bool opaque);
void ovl_dentry_set_opaque(struct dentry *dentry);
bool ovl_redirect_dir(struct super_block *sb);
void ovl_clear_redirect_dir(struct super_block *sb);
const char *ovl_dentry_get_redirect(struct dentry *dentry);

5
fs/overlayfs/util.c
View file

@ -170,10 +170,11 @@ bool ovl_dentry_is_whiteout(struct dentry *dentry)
return !dentry->d_inode && ovl_dentry_is_opaque(dentry);
}
void ovl_dentry_set_opaque(struct dentry *dentry, bool opaque)
void ovl_dentry_set_opaque(struct dentry *dentry)
{
struct ovl_entry *oe = dentry->d_fsdata;
oe->opaque = opaque;
oe->opaque = true;
}
bool ovl_redirect_dir(struct super_block *sb)