[PATCH 03/10] btrfs: tests: use eb folio helpers in extent buffer memory checks

[Tal Zussman]

dump_eb_and_memory_contents() and verify_eb_and_memory() hardcode one
page per folio instead of using get_eb_folio_index() and
get_eb_offset_in_folio() like the rest of the extent buffer code. Use
the helpers and folio_address(). This removes the last struct page usage
in the file.

No functional change. The tests only run with sectorsize == PAGE_SIZE,
and the test extent buffers are backed by order-0 folios.

Assisted-by: Claude:claude-fable-5-1
Signed-off-by: Tal Zussman <tz2294@xxxxxxxxxxxx>
---
 fs/btrfs/tests/extent-io-tests.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/fs/btrfs/tests/extent-io-tests.c b/fs/btrfs/tests/extent-io-tests.c
index 3056dd934b54..7a68b321608e 100644
--- a/fs/btrfs/tests/extent-io-tests.c
+++ b/fs/btrfs/tests/extent-io-tests.c
@@ -669,8 +669,9 @@ static void dump_eb_and_memory_contents(struct extent_buffer *eb, void *memory,
 					const char *test_name)
 {
 	for (int i = 0; i < eb->len; i++) {
-		struct page *page = folio_page(eb->folios[i >> PAGE_SHIFT], 0);
-		void *addr = page_address(page) + offset_in_page(i);
+		const unsigned long idx = get_eb_folio_index(eb, i);
+		void *addr = folio_address(eb->folios[idx]) +
+			     get_eb_offset_in_folio(eb, i);
 
 		if (memcmp(addr, memory + i, 1) != 0) {
 			test_err("%s failed", test_name);
@@ -685,9 +686,12 @@ static int verify_eb_and_memory(struct extent_buffer *eb, void *memory,
 				const char *test_name)
 {
 	for (int i = 0; i < (eb->len >> PAGE_SHIFT); i++) {
-		void *eb_addr = folio_address(eb->folios[i]);
+		const unsigned long offset = i << PAGE_SHIFT;
+		const unsigned long idx = get_eb_folio_index(eb, offset);
+		void *eb_addr = folio_address(eb->folios[idx]) +
+				get_eb_offset_in_folio(eb, offset);
 
-		if (memcmp(memory + (i << PAGE_SHIFT), eb_addr, PAGE_SIZE) != 0) {
+		if (memcmp(memory + offset, eb_addr, PAGE_SIZE) != 0) {
 			dump_eb_and_memory_contents(eb, memory, test_name);
 			return -EUCLEAN;
 		}

-- 
2.39.5