default to simple_setattr
With the new truncate sequence every filesystem that wants to support file
size changes on disk needs to implement its own ->setattr. So instead
of calling inode_setattr which supports size changes call into a simple
method that doesn't support this. simple_setattr is almost what we
want except that it does not mark the inode dirty after changes. Given
that marking the inode dirty is a no-op for the simple in-memory filesystems
that use simple_setattr currently just add the mark_inode_dirty call.
Also add a WARN_ON for the presence of a truncate method to simple_setattr
to catch new instances of it during the transition period.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/attr.c b/fs/attr.c
index 1f6a895..aeac826 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -237,13 +237,10 @@
if (ia_valid & ATTR_SIZE)
down_write(&dentry->d_inode->i_alloc_sem);
- if (inode->i_op && inode->i_op->setattr) {
+ if (inode->i_op->setattr)
error = inode->i_op->setattr(dentry, attr);
- } else {
- error = inode_change_ok(inode, attr);
- if (!error)
- error = inode_setattr(inode, attr);
- }
+ else
+ error = simple_setattr(dentry, attr);
if (ia_valid & ATTR_SIZE)
up_write(&dentry->d_inode->i_alloc_sem);
diff --git a/fs/libfs.c b/fs/libfs.c
index 861a887..4056222 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -370,21 +370,26 @@
EXPORT_SYMBOL(simple_setsize);
/**
- * simple_setattr - setattr for simple in-memory filesystem
+ * simple_setattr - setattr for simple filesystem
* @dentry: dentry
* @iattr: iattr structure
*
* Returns 0 on success, -error on failure.
*
- * simple_setattr implements setattr for an in-memory filesystem which
- * does not store its own file data or metadata (eg. uses the page cache
- * and inode cache as its data store).
+ * simple_setattr is a simple ->setattr implementation without a proper
+ * implementation of size changes.
+ *
+ * It can either be used for in-memory filesystems or special files
+ * on simple regular filesystems. Anything that needs to change on-disk
+ * or wire state on size changes needs its own setattr method.
*/
int simple_setattr(struct dentry *dentry, struct iattr *iattr)
{
struct inode *inode = dentry->d_inode;
int error;
+ WARN_ON_ONCE(inode->i_op->truncate);
+
error = inode_change_ok(inode, iattr);
if (error)
return error;
@@ -396,7 +401,8 @@
}
setattr_copy(inode, iattr);
- return error;
+ mark_inode_dirty(inode);
+ return 0;
}
EXPORT_SYMBOL(simple_setattr);
