ovl: remove the 'locked' argument of ovl_nlink_{start,end}

It just makes the interface strange without adding any significant value.
The only case where locked is false and return value is 0 is in
ovl_rename() when new is negative, so handle that case explicitly in
ovl_rename().

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index e1a55ec..e03f395 100644 (file)
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -652,7 +652,6 @@ static int ovl_link(struct dentry *old, struct inode *newdir,
                    struct dentry *new)
 {
        int err;
-       bool locked = false;
        struct inode *inode;
 
        err = ovl_want_write(old);
@@ -673,7 +672,7 @@ static int ovl_link(struct dentry *old, struct inode *newdir,
                        goto out_drop_write;
        }
 
-       err = ovl_nlink_start(old, &locked);
+       err = ovl_nlink_start(old);
        if (err)
                goto out_drop_write;
 
@@ -686,7 +685,7 @@ static int ovl_link(struct dentry *old, struct inode *newdir,
        if (err)
                iput(inode);
 
-       ovl_nlink_end(old, locked);
+       ovl_nlink_end(old);
 out_drop_write:
        ovl_drop_write(old);
 out:
@@ -811,7 +810,6 @@ static bool ovl_pure_upper(struct dentry *dentry)
 static int ovl_do_remove(struct dentry *dentry, bool is_dir)
 {
        int err;
-       bool locked = false;
        const struct cred *old_cred;
        struct dentry *upperdentry;
        bool lower_positive = ovl_lower_positive(dentry);
@@ -832,7 +830,7 @@ static int ovl_do_remove(struct dentry *dentry, bool is_dir)
        if (err)
                goto out_drop_write;
 
-       err = ovl_nlink_start(dentry, &locked);
+       err = ovl_nlink_start(dentry);
        if (err)
                goto out_drop_write;
 
@@ -848,7 +846,7 @@ static int ovl_do_remove(struct dentry *dentry, bool is_dir)
                else
                        drop_nlink(dentry->d_inode);
        }
-       ovl_nlink_end(dentry, locked);
+       ovl_nlink_end(dentry);
 
        /*
         * Copy ctime
@@ -1012,7 +1010,6 @@ static int ovl_rename(struct inode *olddir, struct dentry *old,
                      unsigned int flags)
 {
        int err;
-       bool locked = false;
        struct dentry *old_upperdir;
        struct dentry *new_upperdir;
        struct dentry *olddentry;
@@ -1021,6 +1018,7 @@ static int ovl_rename(struct inode *olddir, struct dentry *old,
        bool old_opaque;
        bool new_opaque;
        bool cleanup_whiteout = false;
+       bool update_nlink = false;
        bool overwrite = !(flags & RENAME_EXCHANGE);
        bool is_dir = d_is_dir(old);
        bool new_is_dir = d_is_dir(new);
@@ -1078,10 +1076,12 @@ static int ovl_rename(struct inode *olddir, struct dentry *old,
                err = ovl_copy_up(new);
                if (err)
                        goto out_drop_write;
-       } else {
-               err = ovl_nlink_start(new, &locked);
+       } else if (d_inode(new)) {
+               err = ovl_nlink_start(new);
                if (err)
                        goto out_drop_write;
+
+               update_nlink = true;
        }
 
        old_cred = ovl_override_creds(old->d_sb);
@@ -1210,7 +1210,8 @@ out_unlock:
        unlock_rename(new_upperdir, old_upperdir);
 out_revert_creds:
        revert_creds(old_cred);
-       ovl_nlink_end(new, locked);
+       if (update_nlink)
+               ovl_nlink_end(new);
 out_drop_write:
        ovl_drop_write(old);
 out:

diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index a3c0d95..b48ef22 100644 (file)
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -271,8 +271,8 @@ bool ovl_test_flag(unsigned long flag, struct inode *inode);
 bool ovl_inuse_trylock(struct dentry *dentry);
 void ovl_inuse_unlock(struct dentry *dentry);
 bool ovl_need_index(struct dentry *dentry);
-int ovl_nlink_start(struct dentry *dentry, bool *locked);
-void ovl_nlink_end(struct dentry *dentry, bool locked);
+int ovl_nlink_start(struct dentry *dentry);
+void ovl_nlink_end(struct dentry *dentry);
 int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir);
 int ovl_check_metacopy_xattr(struct dentry *dentry);
 bool ovl_is_metacopy_dentry(struct dentry *dentry);

diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index 8cd37ba..d3a7860 100644 (file)
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -738,14 +738,14 @@ fail:
  * Operations that change overlay inode and upper inode nlink need to be
  * synchronized with copy up for persistent nlink accounting.
  */
-int ovl_nlink_start(struct dentry *dentry, bool *locked)
+int ovl_nlink_start(struct dentry *dentry)
 {
        struct ovl_inode *oi = OVL_I(d_inode(dentry));
        const struct cred *old_cred;
        int err;
 
-       if (!d_inode(dentry))
-               return 0;
+       if (WARN_ON(!d_inode(dentry)))
+               return -ENOENT;
 
        /*
         * With inodes index is enabled, we store the union overlay nlink
@@ -787,26 +787,22 @@ int ovl_nlink_start(struct dentry *dentry, bool *locked)
 out:
        if (err)
                mutex_unlock(&oi->lock);
-       else
-               *locked = true;
 
        return err;
 }
 
-void ovl_nlink_end(struct dentry *dentry, bool locked)
+void ovl_nlink_end(struct dentry *dentry)
 {
-       if (locked) {
-               if (ovl_test_flag(OVL_INDEX, d_inode(dentry)) &&
-                   d_inode(dentry)->i_nlink == 0) {
-                       const struct cred *old_cred;
-
-                       old_cred = ovl_override_creds(dentry->d_sb);
-                       ovl_cleanup_index(dentry);
-                       revert_creds(old_cred);
-               }
+       if (ovl_test_flag(OVL_INDEX, d_inode(dentry)) &&
+           d_inode(dentry)->i_nlink == 0) {
+               const struct cred *old_cred;
 
-               mutex_unlock(&OVL_I(d_inode(dentry))->lock);
+               old_cred = ovl_override_creds(dentry->d_sb);
+               ovl_cleanup_index(dentry);
+               revert_creds(old_cred);
        }
+
+       mutex_unlock(&OVL_I(d_inode(dentry))->lock);
 }
 
 int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir)