ocfs2: teach ocfs2_file_aio_write() about sparse files

Unfortunately, ocfs2 can no longer make use of generic_file_aio_write_nlock()
because allocating writes will require zeroing of pages adjacent to the I/O
for cluster sizes greater than page size.

Implement a custom file write here, which can order page locks for zeroing.
This also has the advantage that cluster locks can easily be ordered outside
of the page locks.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/fs/ocfs2/file.h b/fs/ocfs2/file.h
index e2f6551604d0..2c4460fced52 100644
--- a/fs/ocfs2/file.h
+++ b/fs/ocfs2/file.h
@@ -46,6 +46,10 @@ int ocfs2_do_extend_allocation(struct ocfs2_super *osb,
                                struct ocfs2_alloc_context *data_ac,
                                struct ocfs2_alloc_context *meta_ac,
                                enum ocfs2_alloc_restarted *reason);
+int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_dinode *di,
+                          u32 clusters_to_add,
+                          struct ocfs2_alloc_context **data_ac,
+                          struct ocfs2_alloc_context **meta_ac);
 int ocfs2_setattr(struct dentry *dentry, struct iattr *attr);
 int ocfs2_getattr(struct vfsmount *mnt, struct dentry *dentry,
                   struct kstat *stat);