Unionfs: branch management/configuration fixes

Remove unnecessary calls to update branch m/ctimes, and use them only when
needed.  Update branch vfsmounts after operations that could cause a copyup.

Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>

diff --git a/fs/unionfs/commonfops.c b/fs/unionfs/commonfops.c
index 491e2ffde8c9b502a7e372b3f700962a633e768e..2add1679ab15cf8a2d8a7f72fcd8833313f92f40 100644 (file)
--- a/fs/unionfs/commonfops.c
+++ b/fs/unionfs/commonfops.c
@@ -604,6 +604,7 @@ out:
        }
 out_nofree:
        if (!err) {
+               unionfs_postcopyup_setmnt(dentry);
                unionfs_copy_attr_times(inode);
                unionfs_check_file(file);
                unionfs_check_inode(inode);
@@ -839,13 +840,9 @@ int unionfs_flush(struct file *file, fl_owner_t id)
 
        }
 
-       /* on success, update our times */
-       unionfs_copy_attr_times(dentry->d_inode);
-       /* parent time could have changed too (async) */
-       unionfs_copy_attr_times(dentry->d_parent->d_inode);
-
 out:
-       unionfs_check_file(file);
+       if (!err)
+               unionfs_check_file(file);
        unionfs_unlock_dentry(file->f_path.dentry);
        unionfs_read_unlock(dentry->d_sb);
        return err;

diff --git a/fs/unionfs/copyup.c b/fs/unionfs/copyup.c
index 9beac01c68b729bffb46bc704935e01938c9a51c..f71bddf40aed93ad969f0f02bf72e1c90f9b7c79 100644 (file)
--- a/fs/unionfs/copyup.c
+++ b/fs/unionfs/copyup.c
@@ -819,7 +819,8 @@ begin:
         * update times of this dentry, but also the parent, because if
         * we changed, the parent may have changed too.
         */
-       unionfs_copy_attr_times(parent_dentry->d_inode);
+       fsstack_copy_attr_times(parent_dentry->d_inode,
+                               lower_parent_dentry->d_inode);
        unionfs_copy_attr_times(child_dentry->d_inode);
 
        parent_dentry = child_dentry;

diff --git a/fs/unionfs/dentry.c b/fs/unionfs/dentry.c
index 17b297dbab373ddab2d0fa4936820c6f00dcb255..a956b9437c0b8c835c3c86cd3785ac186198add4 100644 (file)
--- a/fs/unionfs/dentry.c
+++ b/fs/unionfs/dentry.c
@@ -482,6 +482,7 @@ static int unionfs_d_revalidate(struct dentry *dentry, struct nameidata *nd)
        unionfs_lock_dentry(dentry, UNIONFS_DMUTEX_CHILD);
        err = __unionfs_d_revalidate_chain(dentry, nd, false);
        if (likely(err > 0)) { /* true==1: dentry is valid */
+               unionfs_postcopyup_setmnt(dentry);
                unionfs_check_dentry(dentry);
                unionfs_check_nd(nd);
        }

diff --git a/fs/unionfs/mmap.c b/fs/unionfs/mmap.c
index ad770acfbc42cb45296dc9b1a629a4f0e972be67..d6ac61e4e8c1f1c31a74ee00aba91940b191fbc4 100644 (file)
--- a/fs/unionfs/mmap.c
+++ b/fs/unionfs/mmap.c
@@ -227,20 +227,11 @@ static int unionfs_prepare_write(struct file *file, struct page *page,
        int err;
 
        unionfs_read_lock(file->f_path.dentry->d_sb, UNIONFS_SMUTEX_PARENT);
-       /*
-        * This is the only place where we unconditionally copy the lower
-        * attribute times before calling unionfs_file_revalidate.  The
-        * reason is that our ->write calls do_sync_write which in turn will
-        * call our ->prepare_write and then ->commit_write.  Before our
-        * ->write is called, the lower mtimes are in sync, but by the time
-        * the VFS calls our ->commit_write, the lower mtimes have changed.
-        * Therefore, the only reasonable time for us to sync up from the
-        * changed lower mtimes, and avoid an invariant violation warning,
-        * is here, in ->prepare_write.
-        */
-       unionfs_copy_attr_times(file->f_path.dentry->d_inode);
        err = unionfs_file_revalidate(file, true);
-       unionfs_check_file(file);
+       if (!err) {
+               unionfs_copy_attr_times(file->f_path.dentry->d_inode);
+               unionfs_check_file(file);
+       }
        unionfs_read_unlock(file->f_path.dentry->d_sb);
 
        return err;

diff --git a/fs/unionfs/rename.c b/fs/unionfs/rename.c
index 5ab13f9f5ec8f1ec796b3bbda2c858fff3ef7a46..cc16eb2989d82daf289d1054e605901438fa956d 100644 (file)
--- a/fs/unionfs/rename.c
+++ b/fs/unionfs/rename.c
@@ -138,6 +138,11 @@ static int __unionfs_rename(struct inode *old_dir, struct dentry *old_dentry,
        err = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
                         lower_new_dir_dentry->d_inode, lower_new_dentry);
 out_err_unlock:
+       if (!err) {
+               /* update parent dir times */
+               fsstack_copy_attr_times(old_dir, lower_old_dir_dentry->d_inode);
+               fsstack_copy_attr_times(new_dir, lower_new_dir_dentry->d_inode);
+       }
        unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
        lockdep_on();
 
@@ -526,8 +531,6 @@ int unionfs_rename(struct inode *old_dir, struct dentry *old_dentry,
                }
        }
        /* if all of this renaming succeeded, update our times */
-       unionfs_copy_attr_times(old_dir);
-       unionfs_copy_attr_times(new_dir);
        unionfs_copy_attr_times(old_dentry->d_inode);
        unionfs_copy_attr_times(new_dentry->d_inode);
        unionfs_check_inode(old_dir);