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 15f4a0ac2dba01a0f2bdad1e151de2d1a2736511..f19c02a0ef099c329da6639a207a119e1d71b418 100644 (file)
--- a/fs/unionfs/commonfops.c
+++ b/fs/unionfs/commonfops.c
@@ -697,6 +697,7 @@ out:
        }
 out_nofree:
        if (!err) {
+               unionfs_postcopyup_setmnt(dentry);
                unionfs_copy_attr_times(inode);
                unionfs_check_file(file);
                unionfs_check_inode(inode);
@@ -920,13 +921,9 @@ 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 9002ec7cbe2ea4e9fdce42a48b890791222b8556..050bd9631457fff8243353142631f721536efc43 100644 (file)
--- a/fs/unionfs/copyup.c
+++ b/fs/unionfs/copyup.c
@@ -825,7 +825,8 @@ 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 5a7fca4eb2373fdba653b25278a872cba84c71f2..85494a9f2d4ee6fcaa62dbdbd2d65315478c1623 100644 (file)
--- a/fs/unionfs/dentry.c
+++ b/fs/unionfs/dentry.c
@@ -500,6 +500,7 @@ 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 19c8fe7135c502866cedfd8ae33330306fa0830d..1396d1af0490abe635cfae7d63960760c3b68cd3 100644 (file)
--- a/fs/unionfs/rename.c
+++ b/fs/unionfs/rename.c
@@ -126,6 +126,11 @@ static int __unionfs_rename(struct inode *old_dir, struct dentry *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();
 
@@ -466,8 +471,6 @@ 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);