ocfs2: Allow direct I/O read past end of file
ocfs2_direct_IO_get_blocks() was incorrectly returning -EIO for a direct I/O
read whose start block was past the end of the file allocation tree. Fix
things so that we return a hole instead. do_direct_IO() will then notice
that the range start is past eof and return a short read.
While there, remove the unused vbo_max variable.
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index ef6cd30..93628b0 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -540,8 +540,7 @@
struct buffer_head *bh_result, int create)
{
int ret;
- u64 vbo_max; /* file offset, max_blocks from iblock */
- u64 p_blkno;
+ u64 p_blkno, inode_blocks;
int contig_blocks;
unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
@@ -550,12 +549,23 @@
* nicely aligned and of the right size, so there's no need
* for us to check any of that. */
- vbo_max = ((u64)iblock + max_blocks) << blocksize_bits;
-
spin_lock(&OCFS2_I(inode)->ip_lock);
- if ((iblock + max_blocks) >
- ocfs2_clusters_to_blocks(inode->i_sb,
- OCFS2_I(inode)->ip_clusters)) {
+ inode_blocks = ocfs2_clusters_to_blocks(inode->i_sb,
+ OCFS2_I(inode)->ip_clusters);
+
+ /*
+ * For a read which begins past the end of file, we return a hole.
+ */
+ if (!create && (iblock >= inode_blocks)) {
+ spin_unlock(&OCFS2_I(inode)->ip_lock);
+ ret = 0;
+ goto bail;
+ }
+
+ /*
+ * Any write past EOF is not allowed because we'd be extending.
+ */
+ if (create && (iblock + max_blocks) > inode_blocks) {
spin_unlock(&OCFS2_I(inode)->ip_lock);
ret = -EIO;
goto bail;
