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/ocfs2.h b/fs/ocfs2/ocfs2.h
index faeb53f..2699f7ca 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -463,6 +463,38 @@
return (unsigned long)((bytes + 511) >> 9);
}
+static inline unsigned int ocfs2_page_index_to_clusters(struct super_block *sb,
+ unsigned long pg_index)
+{
+ u32 clusters = pg_index;
+ unsigned int cbits = OCFS2_SB(sb)->s_clustersize_bits;
+
+ if (unlikely(PAGE_CACHE_SHIFT > cbits))
+ clusters = pg_index << (PAGE_CACHE_SHIFT - cbits);
+ else if (PAGE_CACHE_SHIFT < cbits)
+ clusters = pg_index >> (cbits - PAGE_CACHE_SHIFT);
+
+ return clusters;
+}
+
+/*
+ * Find the 1st page index which covers the given clusters.
+ */
+static inline unsigned long ocfs2_align_clusters_to_page_index(struct super_block *sb,
+ u32 clusters)
+{
+ unsigned int cbits = OCFS2_SB(sb)->s_clustersize_bits;
+ unsigned long index = clusters;
+
+ if (PAGE_CACHE_SHIFT > cbits) {
+ index = clusters >> (PAGE_CACHE_SHIFT - cbits);
+ } else if (PAGE_CACHE_SHIFT < cbits) {
+ index = clusters << (cbits - PAGE_CACHE_SHIFT);
+ }
+
+ return index;
+}
+
#define ocfs2_set_bit ext2_set_bit
#define ocfs2_clear_bit ext2_clear_bit
#define ocfs2_test_bit ext2_test_bit