The lower stacks of all the ovl inode aliases should be identical
and there is redundant information in ovl_entry and ovl_inode.
Move lowerstack into ovl_inode and keep only the OVL_E_FLAGS
per overlay dentry.
Following patches will deduplicate redundant ovl_inode fields.
Note that for a negative dentry, OVL_E(dentry) can now be NULL,
so it is imporatnt to use the ovl_numlower() accessor.
Reviewed-by: Alexander Larsson <alexl@xxxxxxxxxx>
Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
---
fs/overlayfs/dir.c | 2 +-
fs/overlayfs/export.c | 22 ++++++++++++----------
fs/overlayfs/inode.c | 8 ++++----
fs/overlayfs/namei.c | 5 ++---
fs/overlayfs/overlayfs.h | 6 ++++--
fs/overlayfs/ovl_entry.h | 36 ++++++++++++++++++------------------
fs/overlayfs/super.c | 18 ++++--------------
fs/overlayfs/util.c | 8 ++++----
8 files changed, 49 insertions(+), 56 deletions(-)
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index 9be52d8013c8..92bdcedfaaec 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -269,7 +269,7 @@ static int ovl_instantiate(struct dentry *dentry, struct inode *inode,
ovl_dir_modified(dentry->d_parent, false);
ovl_dentry_set_upper_alias(dentry);
- ovl_dentry_init_reval(dentry, newdentry);
+ ovl_dentry_init_reval(dentry, newdentry, NULL);
if (!hardlink) {
/*
diff --git a/fs/overlayfs/export.c b/fs/overlayfs/export.c
index ddb546627749..be142ea73fad 100644
--- a/fs/overlayfs/export.c
+++ b/fs/overlayfs/export.c
@@ -286,7 +286,7 @@ static struct dentry *ovl_obtain_alias(struct super_block *sb,
struct dentry *lower = lowerpath ? lowerpath->dentry : NULL;
struct dentry *upper = upper_alias ?: index;
struct dentry *dentry;
- struct inode *inode;
+ struct inode *inode = NULL;
struct ovl_entry *oe;
struct ovl_inode_params oip = {
.lowerpath = lowerpath,
@@ -298,9 +298,19 @@ static struct dentry *ovl_obtain_alias(struct super_block *sb,
if (d_is_dir(upper ?: lower))
return ERR_PTR(-EIO);
+ oe = ovl_alloc_entry(!!lower);
+ if (!oe)
+ return ERR_PTR(-ENOMEM);
+
oip.upperdentry = dget(upper);
+ if (lower) {
+ ovl_lowerstack(oe)->dentry = dget(lower);
+ ovl_lowerstack(oe)->layer = lowerpath->layer;
+ }
+ oip.oe = oe;
inode = ovl_get_inode(sb, &oip);
if (IS_ERR(inode)) {
+ ovl_free_entry(oe);
dput(upper);
return ERR_CAST(inode);
}
@@ -315,19 +325,11 @@ static struct dentry *ovl_obtain_alias(struct super_block *sb,
dentry = d_alloc_anon(inode->i_sb);
if (unlikely(!dentry))
goto nomem;
- oe = ovl_alloc_entry(lower ? 1 : 0);
- if (!oe)
- goto nomem;
- if (lower) {
- ovl_lowerstack(oe)->dentry = dget(lower);
- ovl_lowerstack(oe)->layer = lowerpath->layer;
- }
- dentry->d_fsdata = oe;
if (upper_alias)
ovl_dentry_set_upper_alias(dentry);
- ovl_dentry_init_reval(dentry, upper);
+ ovl_dentry_init_reval(dentry, upper, OVL_I_E(inode));
return d_instantiate_anon(dentry, inode);
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 541cf3717fc2..c296bd656858 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -1003,8 +1003,9 @@ void ovl_inode_init(struct inode *inode, struct ovl_inode_params *oip,
struct inode *realinode;
struct ovl_inode *oi = OVL_I(inode);
- if (oip->upperdentry)
- oi->__upperdentry = oip->upperdentry;
+ oi->__upperdentry = oip->upperdentry;
+ oi->oe = oip->oe;
+ oi->redirect = oip->redirect;
if (oip->lowerpath && oip->lowerpath->dentry) {
oi->lowerpath.dentry = dget(oip->lowerpath->dentry);
oi->lowerpath.layer = oip->lowerpath->layer;
@@ -1369,6 +1370,7 @@ struct inode *ovl_get_inode(struct super_block *sb,
}
dput(upperdentry);
+ ovl_free_entry(oip->oe);
kfree(oip->redirect);
goto out;
}
@@ -1398,8 +1400,6 @@ struct inode *ovl_get_inode(struct super_block *sb,
if (oip->index)
ovl_set_flag(OVL_INDEX, inode);
- OVL_I(inode)->redirect = oip->redirect;
-
if (bylower)
ovl_set_flag(OVL_CONST_INO, inode);
diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c
index c237c8dbff09..a0a1c498dbd1 100644
--- a/fs/overlayfs/namei.c
+++ b/fs/overlayfs/namei.c
@@ -1073,7 +1073,6 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
goto out_put;
ovl_stack_cpy(ovl_lowerstack(oe), stack, ctr);
- dentry->d_fsdata = oe;
if (upperopaque)
ovl_dentry_set_opaque(dentry);
@@ -1107,6 +1106,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
struct ovl_inode_params oip = {
.upperdentry = upperdentry,
.lowerpath = stack,
+ .oe = oe,
.index = index,
.numlower = ctr,
.redirect = upperredirect,
@@ -1122,7 +1122,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
ovl_set_flag(OVL_UPPERDATA, inode);
}
- ovl_dentry_init_reval(dentry, upperdentry);
+ ovl_dentry_init_reval(dentry, upperdentry, OVL_I_E(inode));
revert_creds(old_cred);
if (origin_path) {
@@ -1135,7 +1135,6 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
return d_splice_alias(inode, dentry);
out_free_oe:
- dentry->d_fsdata = NULL;
ovl_free_entry(oe);
out_put:
dput(index);
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 6a50296fef8f..e14ca0fd1063 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -381,9 +381,10 @@ struct ovl_entry *ovl_alloc_entry(unsigned int numlower);
void ovl_free_entry(struct ovl_entry *oe);
bool ovl_dentry_remote(struct dentry *dentry);
void ovl_dentry_update_reval(struct dentry *dentry, struct dentry *realdentry);
-void ovl_dentry_init_reval(struct dentry *dentry, struct dentry *upperdentry);
+void ovl_dentry_init_reval(struct dentry *dentry, struct dentry *upperdentry,
+ struct ovl_entry *oe);
void ovl_dentry_init_flags(struct dentry *dentry, struct dentry *upperdentry,
- unsigned int mask);
+ struct ovl_entry *oe, unsigned int mask);
bool ovl_dentry_weird(struct dentry *dentry);
enum ovl_path_type ovl_path_type(struct dentry *dentry);
void ovl_path_upper(struct dentry *dentry, struct path *path);
@@ -653,6 +654,7 @@ struct ovl_inode_params {
struct inode *newinode;
struct dentry *upperdentry;
struct ovl_path *lowerpath;
+ struct ovl_entry *oe;
bool index;
unsigned int numlower;
char *redirect;
diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h
index 608742f60037..f511ac78c5bd 100644
--- a/fs/overlayfs/ovl_entry.h
+++ b/fs/overlayfs/ovl_entry.h
@@ -47,6 +47,11 @@ struct ovl_path {
struct dentry *dentry;
};
+struct ovl_entry {
+ unsigned int __numlower;
+ struct ovl_path __lowerstack[];
+};
+
/* private information held for overlayfs's superblock */
struct ovl_fs {
unsigned int numlayer;
@@ -105,18 +110,6 @@ static inline bool ovl_should_sync(struct ovl_fs *ofs)
return !ofs->config.ovl_volatile;
}
-/* private information held for every overlayfs dentry */
-struct ovl_entry {
- union {
- struct {
- unsigned long flags;
- };
- struct rcu_head rcu;
- };
- unsigned int __numlower;
- struct ovl_path __lowerstack[];
-};
-
static inline unsigned int ovl_numlower(struct ovl_entry *oe)
{
return oe ? oe->__numlower : 0;
@@ -127,14 +120,10 @@ static inline struct ovl_path *ovl_lowerstack(struct ovl_entry *oe)
return ovl_numlower(oe) ? oe->__lowerstack : NULL;
}
-static inline struct ovl_entry *OVL_E(struct dentry *dentry)
-{
- return (struct ovl_entry *) dentry->d_fsdata;
-}
-
+/* private information held for every overlayfs dentry */
static inline unsigned long *OVL_E_FLAGS(struct dentry *dentry)
{
- return &OVL_E(dentry)->flags;
+ return (unsigned long *) &dentry->d_fsdata;
}
struct ovl_inode {
@@ -148,6 +137,7 @@ struct ovl_inode {
struct inode vfs_inode;
struct dentry *__upperdentry;
struct ovl_path lowerpath;
+ struct ovl_entry *oe;
/* synchronize copy up and more */
struct mutex lock;
@@ -158,6 +148,16 @@ static inline struct ovl_inode *OVL_I(struct inode *inode)
return container_of(inode, struct ovl_inode, vfs_inode);
}
+static inline struct ovl_entry *OVL_I_E(struct inode *inode)
+{
+ return inode ? OVL_I(inode)->oe : NULL;
+}
+
+static inline struct ovl_entry *OVL_E(struct dentry *dentry)
+{
+ return OVL_I_E(d_inode(dentry));
+}
+
static inline struct dentry *ovl_upperdentry_dereference(struct ovl_inode *oi)
{
return READ_ONCE(oi->__upperdentry);
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index d8fe857bd7e1..b9e62ccd609f 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -59,16 +59,6 @@ module_param_named(metacopy, ovl_metacopy_def, bool, 0644);
MODULE_PARM_DESC(metacopy,
"Default to on or off for the metadata only copy up feature");
-static void ovl_dentry_release(struct dentry *dentry)
-{
- struct ovl_entry *oe = dentry->d_fsdata;
-
- if (oe) {
- ovl_stack_put(ovl_lowerstack(oe), ovl_numlower(oe));
- kfree_rcu(oe, rcu);
- }
-}
-
static struct dentry *ovl_d_real(struct dentry *dentry,
const struct inode *inode)
{
@@ -162,7 +152,6 @@ static int ovl_dentry_weak_revalidate(struct dentry *dentry, unsigned int flags)
}
static const struct dentry_operations ovl_dentry_operations = {
- .d_release = ovl_dentry_release,
.d_real = ovl_d_real,
.d_revalidate = ovl_dentry_revalidate,
.d_weak_revalidate = ovl_dentry_weak_revalidate,
@@ -182,6 +171,7 @@ static struct inode *ovl_alloc_inode(struct super_block *sb)
oi->version = 0;
oi->flags = 0;
oi->__upperdentry = NULL;
+ oi->oe = NULL;
oi->lowerpath.dentry = NULL;
oi->lowerpath.layer = NULL;
oi->lowerdata = NULL;
@@ -205,6 +195,7 @@ static void ovl_destroy_inode(struct inode *inode)
dput(oi->__upperdentry);
dput(oi->lowerpath.dentry);
+ ovl_free_entry(oi->oe);
if (S_ISDIR(inode->i_mode))
ovl_dir_cache_free(inode);
else
@@ -1857,14 +1848,13 @@ static struct dentry *ovl_get_root(struct super_block *sb,
struct ovl_inode_params oip = {
.upperdentry = upperdentry,
.lowerpath = lowerpath,
+ .oe = oe,
};
root = d_make_root(ovl_new_inode(sb, S_IFDIR, 0));
if (!root)
return NULL;
- root->d_fsdata = oe;
-
if (upperdentry) {
/* Root inode uses upper st_ino/i_ino */
ino = d_inode(upperdentry)->i_ino;
@@ -1879,7 +1869,7 @@ static struct dentry *ovl_get_root(struct super_block *sb,
ovl_dentry_set_flag(OVL_E_CONNECTED, root);
ovl_set_upperdata(d_inode(root));
ovl_inode_init(d_inode(root), &oip, ino, fsid);
- ovl_dentry_init_flags(root, upperdentry, DCACHE_OP_WEAK_REVALIDATE);
+ ovl_dentry_init_flags(root, upperdentry, oe, DCACHE_OP_WEAK_REVALIDATE);
return root;
}
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index 1ba6dbea808c..f5e2c70a57f8 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -145,15 +145,15 @@ void ovl_dentry_update_reval(struct dentry *dentry, struct dentry *realdentry)
spin_unlock(&dentry->d_lock);
}
-void ovl_dentry_init_reval(struct dentry *dentry, struct dentry *upperdentry)
+void ovl_dentry_init_reval(struct dentry *dentry, struct dentry *upperdentry,
+ struct ovl_entry *oe)
{
- return ovl_dentry_init_flags(dentry, upperdentry, OVL_D_REVALIDATE);
+ return ovl_dentry_init_flags(dentry, upperdentry, oe, OVL_D_REVALIDATE);
}
void ovl_dentry_init_flags(struct dentry *dentry, struct dentry *upperdentry,
- unsigned int mask)
+ struct ovl_entry *oe, unsigned int mask)
{
- struct ovl_entry *oe = OVL_E(dentry);
struct ovl_path *lowerstack = ovl_lowerstack(oe);
unsigned int i, flags = 0;
--
2.34.1
