[igt-dev] [PATCH i-g-t] i915/gem_tiled_w[bc]: Tighten computation of upper bound

[Chris Wilson]

Fix the off-by-one in computing the last page that caused us to try and
mmap the page beyond the end of the object.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 tests/i915/gem_tiled_wb.c | 4 ++--
 tests/i915/gem_tiled_wc.c | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/tests/i915/gem_tiled_wb.c b/tests/i915/gem_tiled_wb.c
index 67d54bd30..827c2d9d6 100644
--- a/tests/i915/gem_tiled_wb.c
+++ b/tests/i915/gem_tiled_wb.c
@@ -174,8 +174,8 @@ igt_simple_main
 			len = size;
 		}
 
-		first_page = offset & ~(PAGE_SIZE-1);
-		last_page = (offset + len + PAGE_SIZE) & ~(PAGE_SIZE-1);
+		first_page = offset & -PAGE_SIZE;
+		last_page = (offset + len + PAGE_SIZE - 1) & -PAGE_SIZE;
 		offset -= first_page;
 
 		linear = gem_mmap__cpu(fd, handle, first_page, last_page - first_page, PROT_READ);
diff --git a/tests/i915/gem_tiled_wc.c b/tests/i915/gem_tiled_wc.c
index 21390729d..67ebbc940 100644
--- a/tests/i915/gem_tiled_wc.c
+++ b/tests/i915/gem_tiled_wc.c
@@ -149,8 +149,8 @@ igt_simple_main
 			len = size;
 		}
 
-		first_page = offset & ~(PAGE_SIZE-1);
-		last_page = (offset + len + PAGE_SIZE) & ~(PAGE_SIZE-1);
+		first_page = offset & -PAGE_SIZE;
+		last_page = (offset + len + PAGE_SIZE - 1) & -PAGE_SIZE;
 
 		linear = gem_mmap__wc(fd, handle, first_page, last_page - first_page, PROT_READ);
 
-- 
2.20.1