ovl: move __upperdentry to ovl_inode

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index e5869f91b3ab2ce1857b774d980fda740bf996fb..87289b9a152c87db80663089b9769ae67f9b15ec 100644 (file)
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -417,8 +417,7 @@ static int ovl_copy_up_locked(struct dentry *workdir, struct dentry *upperdir,
                goto out_cleanup;
 
        newdentry = dget(tmpfile ? upper : temp);
-       ovl_dentry_update(dentry, newdentry);
-       ovl_inode_update(d_inode(dentry), d_inode(newdentry));
+       ovl_inode_update(d_inode(dentry), newdentry);
 
        /* Restore timestamps on parent (best effort) */
        ovl_set_timestamps(upperdir, pstat);

diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index 59e0dc9897fbb21c977d6e90ade93d052d279b9b..d0d6292e069a617574d7b149d2d02252372c3fb1 100644 (file)
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -154,12 +154,12 @@ static void ovl_instantiate(struct dentry *dentry, struct inode *inode,
                            struct dentry *newdentry, bool hardlink)
 {
        ovl_dentry_version_inc(dentry->d_parent);
-       ovl_dentry_update(dentry, newdentry);
        if (!hardlink) {
-               ovl_inode_update(inode, d_inode(newdentry));
+               ovl_inode_update(inode, newdentry);
                ovl_copyattr(newdentry->d_inode, inode);
        } else {
-               WARN_ON(ovl_inode_real(inode, NULL) != d_inode(newdentry));
+               WARN_ON(ovl_inode_real(inode) != d_inode(newdentry));
+               dput(newdentry);
                inc_nlink(inode);
        }
        d_instantiate(dentry, inode);
@@ -1003,7 +1003,7 @@ static int ovl_rename(struct inode *olddir, struct dentry *old,
        new_opaque = ovl_dentry_is_opaque(new);
 
        err = -ESTALE;
-       if (ovl_dentry_upper(new)) {
+       if (d_inode(new) && ovl_dentry_upper(new)) {
                if (opaquedir) {
                        if (newdentry != opaquedir)
                                goto out_dput;

diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 4c30d44905efa402ff572a6962abdd79bf87f798..4654c03dd508d41d7d89d1c08e00f5e67500b36a 100644 (file)
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -134,8 +134,8 @@ out:
 
 int ovl_permission(struct inode *inode, int mask)
 {
-       bool is_upper;
-       struct inode *realinode = ovl_inode_real(inode, &is_upper);
+       struct inode *upperinode = ovl_inode_upper(inode);
+       struct inode *realinode = upperinode ?: ovl_inode_lower(inode);
        const struct cred *old_cred;
        int err;
 
@@ -154,7 +154,8 @@ int ovl_permission(struct inode *inode, int mask)
                return err;
 
        old_cred = ovl_override_creds(inode->i_sb);
-       if (!is_upper && !special_file(realinode->i_mode) && mask & MAY_WRITE) {
+       if (!upperinode &&
+           !special_file(realinode->i_mode) && mask & MAY_WRITE) {
                mask &= ~(MAY_WRITE | MAY_APPEND);
                /* Make sure mounter can read file for copy up later */
                mask |= MAY_READ;
@@ -286,7 +287,7 @@ ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size)
 
 struct posix_acl *ovl_get_acl(struct inode *inode, int type)
 {
-       struct inode *realinode = ovl_inode_real(inode, NULL);
+       struct inode *realinode = ovl_inode_real(inode);
        const struct cred *old_cred;
        struct posix_acl *acl;
 
@@ -462,17 +463,24 @@ static int ovl_inode_set(struct inode *inode, void *data)
        return 0;
 }
 
-struct inode *ovl_get_inode(struct dentry *dentry)
+struct inode *ovl_get_inode(struct dentry *dentry, struct dentry *upperdentry)
 {
-       struct dentry *upperdentry = ovl_dentry_upper(dentry);
-       struct inode *realinode = d_inode(ovl_dentry_real(dentry));
+       struct dentry *lowerdentry = ovl_dentry_lower(dentry);
+       struct inode *realinode = upperdentry ? d_inode(upperdentry) : NULL;
        struct inode *inode;
 
+       if (!realinode)
+               realinode = d_inode(lowerdentry);
+
        if (upperdentry && !d_is_dir(upperdentry)) {
                inode = iget5_locked(dentry->d_sb, (unsigned long) realinode,
                                     ovl_inode_test, ovl_inode_set, realinode);
-               if (!inode || !(inode->i_state & I_NEW))
+               if (!inode)
                        goto out;
+               if (!(inode->i_state & I_NEW)) {
+                       dput(upperdentry);
+                       goto out;
+               }
 
                set_nlink(inode, realinode->i_nlink);
        } else {
@@ -481,7 +489,7 @@ struct inode *ovl_get_inode(struct dentry *dentry)
                        goto out;
        }
        ovl_fill_inode(inode, realinode->i_mode, realinode->i_rdev);
-       ovl_inode_init(inode, dentry);
+       ovl_inode_init(inode, upperdentry, lowerdentry);
        if (inode->i_state & I_NEW)
                unlock_new_inode(inode);
 out:

diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c
index 0072ca5d5dace7be15df10dfb98b2b2cd074db4c..1f873e2e8a79389651791e0b0dde5171c27abe39 100644 (file)
--- a/fs/overlayfs/namei.c
+++ b/fs/overlayfs/namei.c
@@ -359,7 +359,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
                return ERR_PTR(-ENAMETOOLONG);
 
        old_cred = ovl_override_creds(dentry->d_sb);
-       upperdir = ovl_upperdentry_dereference(poe);
+       upperdir = ovl_dentry_upper(dentry->d_parent);
        if (upperdir) {
                err = ovl_lookup_layer(upperdir, &d, &upperdentry);
                if (err)
@@ -436,13 +436,12 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
        oe->opaque = upperopaque;
        oe->impure = upperimpure;
        oe->redirect = upperredirect;
-       oe->__upperdentry = upperdentry;
        memcpy(oe->lowerstack, stack, sizeof(struct path) * ctr);
        dentry->d_fsdata = oe;
 
        if (upperdentry || ctr) {
                err = -ENOMEM;
-               inode = ovl_get_inode(dentry);
+               inode = ovl_get_inode(dentry, upperdentry);
                if (!inode)
                        goto out_free_oe;
        }
@@ -487,7 +486,7 @@ bool ovl_lower_positive(struct dentry *dentry)
                return oe->opaque;
 
        /* Negative upper -> positive lower */
-       if (!oe->__upperdentry)
+       if (!ovl_dentry_upper(dentry))
                return true;
 
        /* Positive upper -> have to look up lower to see whether it exists */

diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 6e6600ae1d5420b85f4443a13f1f4699fcab341e..83607f883ace86fd83fbdb9aaab2e3f32db0423d 100644 (file)
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -189,7 +189,9 @@ enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path);
 struct dentry *ovl_dentry_upper(struct dentry *dentry);
 struct dentry *ovl_dentry_lower(struct dentry *dentry);
 struct dentry *ovl_dentry_real(struct dentry *dentry);
-struct inode *ovl_inode_real(struct inode *inode, bool *is_upper);
+struct inode *ovl_inode_upper(struct inode *inode);
+struct inode *ovl_inode_lower(struct inode *inode);
+struct inode *ovl_inode_real(struct inode *inode);
 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);
@@ -199,9 +201,9 @@ void ovl_dentry_set_opaque(struct dentry *dentry);
 bool ovl_redirect_dir(struct super_block *sb);
 const char *ovl_dentry_get_redirect(struct dentry *dentry);
 void ovl_dentry_set_redirect(struct dentry *dentry, const char *redirect);
-void ovl_dentry_update(struct dentry *dentry, struct dentry *upperdentry);
-void ovl_inode_init(struct inode *inode, struct dentry *dentry);
-void ovl_inode_update(struct inode *inode, struct inode *upperinode);
+void ovl_inode_init(struct inode *inode, struct dentry *upperdentry,
+                   struct dentry *lowerdentry);
+void ovl_inode_update(struct inode *inode, struct dentry *upperdentry);
 void ovl_dentry_version_inc(struct dentry *dentry);
 u64 ovl_dentry_version_get(struct dentry *dentry);
 bool ovl_is_whiteout(struct dentry *dentry);
@@ -250,7 +252,7 @@ int ovl_update_time(struct inode *inode, struct timespec *ts, int flags);
 bool ovl_is_private_xattr(const char *name);
 
 struct inode *ovl_new_inode(struct super_block *sb, umode_t mode, dev_t rdev);
-struct inode *ovl_get_inode(struct dentry *dentry);
+struct inode *ovl_get_inode(struct dentry *dentry, struct dentry *upperdentry);
 static inline void ovl_copyattr(struct inode *from, struct inode *to)
 {
        to->i_uid = from->i_uid;

diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h
index b8c213891e84ab82bd44065a70723d4433aab509..ddd937490f0dcbf89274a57bc8d4cfd30ef38a7d 100644 (file)
--- a/fs/overlayfs/ovl_entry.h
+++ b/fs/overlayfs/ovl_entry.h
@@ -36,7 +36,6 @@ struct ovl_fs {
 
 /* private information held for every overlayfs dentry */
 struct ovl_entry {
-       struct dentry *__upperdentry;
        struct ovl_dir_cache *cache;
        union {
                struct {
@@ -54,14 +53,9 @@ struct ovl_entry {
 
 struct ovl_entry *ovl_alloc_entry(unsigned int numlower);
 
-static inline struct dentry *ovl_upperdentry_dereference(struct ovl_entry *oe)
-{
-       return lockless_dereference(oe->__upperdentry);
-}
-
 struct ovl_inode {
        struct inode vfs_inode;
-       struct inode *upper;
+       struct dentry *__upperdentry;
        struct inode *lower;
 };
 
@@ -69,3 +63,8 @@ static inline struct ovl_inode *OVL_I(struct inode *inode)
 {
        return container_of(inode, struct ovl_inode, vfs_inode);
 }
+
+static inline struct dentry *ovl_upperdentry_dereference(struct ovl_inode *oi)
+{
+       return lockless_dereference(oi->__upperdentry);
+}

diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index c166c1d76890b69e2bd4cf9f4ba6707d80bd6bf9..1b865716110a18b7dd8b94789e81197c9f49d88a 100644 (file)
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -41,7 +41,6 @@ static void ovl_dentry_release(struct dentry *dentry)
        if (oe) {
                unsigned int i;
 
-               dput(oe->__upperdentry);
                kfree(oe->redirect);
                for (i = 0; i < oe->numlower; i++)
                        dput(oe->lowerstack[i].dentry);
@@ -171,7 +170,7 @@ static struct inode *ovl_alloc_inode(struct super_block *sb)
 {
        struct ovl_inode *oi = kmem_cache_alloc(ovl_inode_cachep, GFP_KERNEL);
 
-       oi->upper = NULL;
+       oi->__upperdentry = NULL;
        oi->lower = NULL;
 
        return &oi->vfs_inode;
@@ -186,6 +185,10 @@ static void ovl_i_callback(struct rcu_head *head)
 
 static void ovl_destroy_inode(struct inode *inode)
 {
+       struct ovl_inode *oi = OVL_I(inode);
+
+       dput(oi->__upperdentry);
+
        call_rcu(&inode->i_rcu, ovl_i_callback);
 }
 
@@ -636,7 +639,7 @@ ovl_posix_acl_xattr_set(const struct xattr_handler *handler,
                        size_t size, int flags)
 {
        struct dentry *workdir = ovl_workdir(dentry);
-       struct inode *realinode = ovl_inode_real(inode, NULL);
+       struct inode *realinode = ovl_inode_real(inode);
        struct posix_acl *acl = NULL;
        int err;
 
@@ -678,7 +681,7 @@ ovl_posix_acl_xattr_set(const struct xattr_handler *handler,
 
        err = ovl_xattr_set(dentry, handler->name, value, size, flags);
        if (!err)
-               ovl_copyattr(ovl_inode_real(inode, NULL), inode);
+               ovl_copyattr(ovl_inode_real(inode), inode);
 
        return err;
 
@@ -1000,7 +1003,6 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
        kfree(lowertmp);
 
        if (upperpath.dentry) {
-               oe->__upperdentry = upperpath.dentry;
                oe->impure = ovl_is_impuredir(upperpath.dentry);
        }
        for (i = 0; i < numlower; i++) {
@@ -1011,7 +1013,8 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
 
        root_dentry->d_fsdata = oe;
 
-       ovl_inode_init(d_inode(root_dentry), root_dentry);
+       ovl_inode_init(d_inode(root_dentry), upperpath.dentry,
+                      ovl_dentry_lower(root_dentry));
 
        sb->s_root = root_dentry;
 

diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index fc7b1447435bb86ea29c419f8f7c4c136013f38b..e5d9e8daa55cb378c6da5bc7658dd584b157b887 100644 (file)
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -78,7 +78,7 @@ enum ovl_path_type ovl_path_type(struct dentry *dentry)
        struct ovl_entry *oe = dentry->d_fsdata;
        enum ovl_path_type type = 0;
 
-       if (oe->__upperdentry) {
+       if (ovl_dentry_upper(dentry)) {
                type = __OVL_PATH_UPPER;
 
                /*
@@ -99,10 +99,9 @@ enum ovl_path_type ovl_path_type(struct dentry *dentry)
 void ovl_path_upper(struct dentry *dentry, struct path *path)
 {
        struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
-       struct ovl_entry *oe = dentry->d_fsdata;
 
        path->mnt = ofs->upper_mnt;
-       path->dentry = ovl_upperdentry_dereference(oe);
+       path->dentry = ovl_dentry_upper(dentry);
 }
 
 void ovl_path_lower(struct dentry *dentry, struct path *path)
@@ -126,51 +125,39 @@ enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path)
 
 struct dentry *ovl_dentry_upper(struct dentry *dentry)
 {
-       struct ovl_entry *oe = dentry->d_fsdata;
-
-       return ovl_upperdentry_dereference(oe);
-}
-
-static struct dentry *__ovl_dentry_lower(struct ovl_entry *oe)
-{
-       return oe->numlower ? oe->lowerstack[0].dentry : NULL;
+       return ovl_upperdentry_dereference(OVL_I(d_inode(dentry)));
 }
 
 struct dentry *ovl_dentry_lower(struct dentry *dentry)
 {
        struct ovl_entry *oe = dentry->d_fsdata;
 
-       return __ovl_dentry_lower(oe);
+       return oe->numlower ? oe->lowerstack[0].dentry : NULL;
 }
 
 struct dentry *ovl_dentry_real(struct dentry *dentry)
 {
-       struct ovl_entry *oe = dentry->d_fsdata;
-       struct dentry *realdentry;
-
-       realdentry = ovl_upperdentry_dereference(oe);
-       if (!realdentry)
-               realdentry = __ovl_dentry_lower(oe);
-
-       return realdentry;
+       return ovl_dentry_upper(dentry) ?: ovl_dentry_lower(dentry);
 }
 
-struct inode *ovl_inode_real(struct inode *inode, bool *is_upper)
+struct inode *ovl_inode_upper(struct inode *inode)
 {
-       struct inode *realinode = lockless_dereference(OVL_I(inode)->upper);
-       bool isup = false;
+       struct dentry *upperdentry = ovl_upperdentry_dereference(OVL_I(inode));
 
-       if (!realinode)
-               realinode = OVL_I(inode)->lower;
-       else
-               isup = true;
+       return upperdentry ? d_inode(upperdentry) : NULL;
+}
 
-       if (is_upper)
-               *is_upper = isup;
+struct inode *ovl_inode_lower(struct inode *inode)
+{
+       return OVL_I(inode)->lower;
+}
 
-       return realinode;
+struct inode *ovl_inode_real(struct inode *inode)
+{
+       return ovl_inode_upper(inode) ?: ovl_inode_lower(inode);
 }
 
+
 struct ovl_dir_cache *ovl_dir_cache(struct dentry *dentry)
 {
        struct ovl_entry *oe = dentry->d_fsdata;
@@ -232,42 +219,30 @@ void ovl_dentry_set_redirect(struct dentry *dentry, const char *redirect)
        oe->redirect = redirect;
 }
 
-void ovl_dentry_update(struct dentry *dentry, struct dentry *upperdentry)
+void ovl_inode_init(struct inode *inode, struct dentry *upperdentry,
+                   struct dentry *lowerdentry)
 {
-       struct ovl_entry *oe = dentry->d_fsdata;
+       if (upperdentry)
+               OVL_I(inode)->__upperdentry = upperdentry;
+       if (lowerdentry)
+               OVL_I(inode)->lower = d_inode(lowerdentry);
 
-       WARN_ON(!inode_is_locked(upperdentry->d_parent->d_inode));
-       WARN_ON(oe->__upperdentry);
-       /*
-        * Make sure upperdentry is consistent before making it visible to
-        * ovl_upperdentry_dereference().
-        */
-       smp_wmb();
-       oe->__upperdentry = upperdentry;
+       ovl_copyattr(d_inode(upperdentry ?: lowerdentry), inode);
 }
 
-void ovl_inode_init(struct inode *inode, struct dentry *dentry)
+void ovl_inode_update(struct inode *inode, struct dentry *upperdentry)
 {
-       struct inode *realinode = d_inode(ovl_dentry_real(dentry));
+       struct inode *upperinode = d_inode(upperdentry);
 
-       if (ovl_dentry_upper(dentry))
-               OVL_I(inode)->upper = realinode;
-       else
-               OVL_I(inode)->lower = realinode;
-
-       ovl_copyattr(realinode, inode);
-}
-
-void ovl_inode_update(struct inode *inode, struct inode *upperinode)
-{
-       WARN_ON(!upperinode);
        WARN_ON(!inode_unhashed(inode));
+       WARN_ON(!inode_is_locked(upperdentry->d_parent->d_inode));
+       WARN_ON(OVL_I(inode)->__upperdentry);
+
        /*
-        * Make sure upperinode is consistent before making it visible to
-        * ovl_inode_real();
+        * Make sure upperdentry is consistent before making it visible
         */
        smp_wmb();
-       OVL_I(inode)->upper = upperinode;
+       OVL_I(inode)->__upperdentry = upperdentry;
        if (!S_ISDIR(upperinode->i_mode)) {
                inode->i_private = upperinode;
                __insert_inode_hash(inode, (unsigned long) upperinode);
@@ -311,7 +286,7 @@ int ovl_copy_up_start(struct dentry *dentry)
        spin_lock(&ofs->copyup_wq.lock);
        err = wait_event_interruptible_locked(ofs->copyup_wq, !oe->copying);
        if (!err) {
-               if (oe->__upperdentry)
+               if (ovl_dentry_upper(dentry))
                        err = 1; /* Already copied up */
                else
                        oe->copying = true;