buffer: Make bh_offset() work for compound pages

[platform/kernel/linux-starfive.git] / include / linux / buffer_head.h

diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h
index 6cb3e9a..4ba2420 100644 (file)
--- a/include/linux/buffer_head.h
+++ b/include/linux/buffer_head.h
@@ -173,7 +173,10 @@ static __always_inline int buffer_uptodate(const struct buffer_head *bh)
        return test_bit_acquire(BH_Uptodate, &bh->b_state);
 }
 
-#define bh_offset(bh)          ((unsigned long)(bh)->b_data & ~PAGE_MASK)
+static inline unsigned long bh_offset(const struct buffer_head *bh)
+{
+       return (unsigned long)(bh)->b_data & (page_size(bh->b_page) - 1);
+}
 
 /* If we *know* page->private refers to buffer_heads */
 #define page_buffers(page)                                     \