From ab1eb5ffb7d2a69c9b24083026a63cbdd758d96b Mon Sep 17 00:00:00 2001
From: Amir Goldstein <amir73il@gmail.com>
Date: Sat, 1 Apr 2023 10:29:19 +0300
Subject: [PATCH] ovl: deduplicate lowerdata and lowerstack[]
The ovl_inode contains a copy of lowerdata in lowerstack[], so the
lowerdata inode member can be removed.
Use accessors ovl_lowerdata*() to get the lowerdata whereever the member
was accessed directly.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
---
fs/overlayfs/inode.c | 2 --
fs/overlayfs/namei.c | 2 --
fs/overlayfs/overlayfs.h | 1 -
fs/overlayfs/ovl_entry.h | 16 +++++++++++++++-
fs/overlayfs/super.c | 3 ---
fs/overlayfs/util.c | 15 +++++++--------
6 files changed, 22 insertions(+), 17 deletions(-)
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 4dbf8d880c0f..5239a5bfc6d1 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -1005,8 +1005,6 @@ void ovl_inode_init(struct inode *inode, struct ovl_inode_params *oip,
oi->__upperdentry = oip->upperdentry;
oi->oe = oip->oe;
oi->redirect = oip->redirect;
- if (oip->lowerdata)
- oi->lowerdata = igrab(d_inode(oip->lowerdata));
realinode = ovl_inode_real(inode);
ovl_copyattr(inode);
diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c
index 317ab1efc236..8ea2a8358a92 100644
--- a/fs/overlayfs/namei.c
+++ b/fs/overlayfs/namei.c
@@ -1110,8 +1110,6 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
.oe = oe,
.index = index,
.redirect = upperredirect,
- .lowerdata = (ctr > 1 && !d.is_dir) ?
- stack[ctr - 1].dentry : NULL,
};
inode = ovl_get_inode(dentry->d_sb, &oip);
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 8b38844ae341..2ccd6326c2c7 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -656,7 +656,6 @@ struct ovl_inode_params {
struct ovl_entry *oe;
bool index;
char *redirect;
- struct dentry *lowerdata;
};
void ovl_inode_init(struct inode *inode, struct ovl_inode_params *oip,
unsigned long ino, int fsid);
diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h
index 0bb8ab3aa8a7..548c93e030fc 100644
--- a/fs/overlayfs/ovl_entry.h
+++ b/fs/overlayfs/ovl_entry.h
@@ -125,6 +125,20 @@ static inline struct ovl_path *ovl_lowerpath(struct ovl_entry *oe)
return ovl_lowerstack(oe);
}
+static inline struct ovl_path *ovl_lowerdata(struct ovl_entry *oe)
+{
+ struct ovl_path *lowerstack = ovl_lowerstack(oe);
+
+ return lowerstack ? &lowerstack[oe->__numlower - 1] : NULL;
+}
+
+static inline struct dentry *ovl_lowerdata_dentry(struct ovl_entry *oe)
+{
+ struct ovl_path *lowerdata = ovl_lowerdata(oe);
+
+ return lowerdata ? lowerdata->dentry : NULL;
+}
+
/* private information held for every overlayfs dentry */
static inline unsigned long *OVL_E_FLAGS(struct dentry *dentry)
{
@@ -134,7 +148,7 @@ static inline unsigned long *OVL_E_FLAGS(struct dentry *dentry)
struct ovl_inode {
union {
struct ovl_dir_cache *cache; /* directory */
- struct inode *lowerdata; /* regular file */
+ /* place holder for non-dir */ /* regular file */
};
const char *redirect;
u64 version;
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 1efc4f252561..dace72ed36c2 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -172,7 +172,6 @@ static struct inode *ovl_alloc_inode(struct super_block *sb)
oi->flags = 0;
oi->__upperdentry = NULL;
oi->oe = NULL;
- oi->lowerdata = NULL;
mutex_init(&oi->lock);
return &oi->vfs_inode;
@@ -195,8 +194,6 @@ static void ovl_destroy_inode(struct inode *inode)
ovl_free_entry(oi->oe);
if (S_ISDIR(inode->i_mode))
ovl_dir_cache_free(inode);
- else
- iput(oi->lowerdata);
}
static void ovl_free_fs(struct ovl_fs *ofs)
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index 143e6898f50d..b6e66bf8135f 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -225,11 +225,11 @@ void ovl_path_lower(struct dentry *dentry, struct path *path)
void ovl_path_lowerdata(struct dentry *dentry, struct path *path)
{
struct ovl_entry *oe = OVL_E(dentry);
- struct ovl_path *lowerstack = ovl_lowerstack(oe);
+ struct ovl_path *lowerdata = ovl_lowerdata(oe);
if (ovl_numlower(oe)) {
- path->mnt = lowerstack[ovl_numlower(oe) - 1].layer->mnt;
- path->dentry = lowerstack[ovl_numlower(oe) - 1].dentry;
+ path->mnt = lowerdata->layer->mnt;
+ path->dentry = lowerdata->dentry;
} else {
*path = (struct path) { };
}
@@ -288,10 +288,7 @@ const struct ovl_layer *ovl_layer_lower(struct dentry *dentry)
*/
struct dentry *ovl_dentry_lowerdata(struct dentry *dentry)
{
- struct ovl_entry *oe = OVL_E(dentry);
-
- return ovl_numlower(oe) ?
- ovl_lowerstack(oe)[ovl_numlower(oe) - 1].dentry : NULL;
+ return ovl_lowerdata_dentry(OVL_E(dentry));
}
struct dentry *ovl_dentry_real(struct dentry *dentry)
@@ -341,10 +338,12 @@ struct inode *ovl_inode_real(struct inode *inode)
/* Return inode which contains lower data. Do not return metacopy */
struct inode *ovl_inode_lowerdata(struct inode *inode)
{
+ struct dentry *lowerdata = ovl_lowerdata_dentry(OVL_I_E(inode));
+
if (WARN_ON(!S_ISREG(inode->i_mode)))
return NULL;
- return OVL_I(inode)->lowerdata ?: ovl_inode_lower(inode);
+ return lowerdata ? d_inode(lowerdata) : NULL;
}
/* Return real inode which contains data. Does not return metacopy inode */