bcachefs: convert eytzinger0_find_le to be 1-based

eytzinger0_find_le() is also easy to concert to 1-based eytzinger (but
see the next commit).

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/eytzinger.h b/fs/bcachefs/eytzinger.h
index 99edae4bb9950b49df875e3d4fc49b1dbf97642c..08256fcaeeb715f66045c97e94a86bd5c5f1161e 100644 (file)
--- a/fs/bcachefs/eytzinger.h
+++ b/fs/bcachefs/eytzinger.h
@@ -253,27 +253,27 @@ static inline unsigned inorder_to_eytzinger0(unsigned i, unsigned size)
 static inline int eytzinger0_find_le(void *base, size_t nr, size_t size,
                                     cmp_func_t cmp, const void *search)
 {
-       unsigned i, n = 0;
+       void *base1 = base - size;
+       unsigned i, n = 1;
 
        if (!nr)
                return -1;
 
        do {
                i = n;
-               n = eytzinger0_child(i, cmp(base + i * size, search) <= 0);
-       } while (n < nr);
+               n = eytzinger1_child(i, cmp(base1 + i * size, search) <= 0);
+       } while (n <= nr);
 
-       if (n & 1) {
+       if (!(n & 1)) {
                /*
                 * @i was greater than @search, return previous node:
                 *
                 * if @i was leftmost/smallest element,
-                * eytzinger0_prev(eytzinger0_first())) returns -1, as expected
+                * eytzinger1_prev(eytzinger1_first())) returns 0, as expected
                 */
-               return eytzinger0_prev(i, nr);
-       } else {
-               return i;
+               i = eytzinger1_prev(i, nr);
        }
+       return i - 1;
 }
 
 static inline int eytzinger0_find_gt(void *base, size_t nr, size_t size,