iomap: enhance writeback error message

If we encounter an IO error during writeback, log the inode, offset, and
sector number of the failure, instead of forcing the user to do some
sort of reverse mapping to figure out which file is affected.

Signed-off-by: Darrick J. Wong <[email protected]>
Reviewed-by: Dave Chinner <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>

fs/iomap/buffered-io.c

@@ -1162,8 +1162,9 @@ iomap_finish_ioend(struct iomap_ioend *ioend, int error)
 
 	if (unlikely(error && !quiet)) {
 		printk_ratelimited(KERN_ERR
-			"%s: writeback error on sector %llu",
-			inode->i_sb->s_id, start);
+"%s: writeback error on inode %lu, offset %lld, sector %llu",
+			inode->i_sb->s_id, inode->i_ino, ioend->io_offset,
+			start);
 	}
 }