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>
diff --git a/fs/ocfs2/aops.h b/fs/ocfs2/aops.h
index f446a15..eeb2c42 100644
--- a/fs/ocfs2/aops.h
+++ b/fs/ocfs2/aops.h
@@ -30,6 +30,44 @@
unsigned from,
unsigned to);
+struct ocfs2_write_ctxt;
+typedef int (ocfs2_page_writer)(struct inode *, struct ocfs2_write_ctxt *,
+ u64 *, unsigned int *, unsigned int *);
+
+ssize_t ocfs2_buffered_write_cluster(struct file *file, loff_t pos,
+ size_t count, ocfs2_page_writer *actor,
+ void *priv);
+
+struct ocfs2_write_ctxt {
+ size_t w_count;
+ loff_t w_pos;
+ u32 w_cpos;
+ unsigned int w_finished_copy;
+
+ /* This is true if page_size > cluster_size */
+ unsigned int w_large_pages;
+
+ /* Filler callback and private data */
+ ocfs2_page_writer *w_write_data_page;
+ void *w_private;
+
+ /* Only valid for the filler callback */
+ struct page *w_this_page;
+ unsigned int w_this_page_new;
+};
+
+struct ocfs2_buffered_write_priv {
+ char *b_src_buf;
+ const struct iovec *b_cur_iov; /* Current iovec */
+ size_t b_cur_off; /* Offset in the
+ * current iovec */
+};
+int ocfs2_map_and_write_user_data(struct inode *inode,
+ struct ocfs2_write_ctxt *wc,
+ u64 *p_blkno,
+ unsigned int *ret_from,
+ unsigned int *ret_to);
+
/* all ocfs2_dio_end_io()'s fault */
#define ocfs2_iocb_is_rw_locked(iocb) \
test_bit(0, (unsigned long *)&iocb->private)