nand: vboot support for small GPTs

This patch makes some small modifications to cgpt and vboot to
root out the last vestigates of a fixed 128-entry GPT:
- Get rid of the TOTAL_ENTRIES_SIZE constant and all users.
- Reduce MAX_NUMBER_OF_ENTRIES to 128 (which is what the GPT
  spec specifies) so that this can be used for things like memory
  allocations without additional overhead.
- Base the amount of GPT read/written on the number of entries
  specified in the GPT header on disk/flash.

BUG=chromium:433433
TEST=make runalltests
TEST=Modified fmap to make an 8k RW_GPT, wrote a GPT with cgpt, then
rebooted and found that the GPT was correctly read after restarting
and the appropriate mtd partitions were present.
BRANCH=none

Change-Id: I45317377da20259caf04a7a4fa077a892b03c45f
Signed-off-by: Dan Ehrenberg <dehrenberg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/238245
Reviewed-by: Randall Spangler <rspangler@chromium.org>

2 files changed, 7 insertions, 2 deletions

diff --git a/tests/cgptlib_test.c b/tests/cgptlib_test.c
index 759fa500..13244a56 100644
--- a/tests/cgptlib_test.c
+++ b/tests/cgptlib_test.c
@@ -42,6 +42,7 @@
 #define DEFAULT_SECTOR_SIZE 512
 #define MAX_SECTOR_SIZE 4096
 #define DEFAULT_DRIVE_SECTORS 467
+#define TOTAL_ENTRIES_SIZE (MAX_NUMBER_OF_ENTRIES * sizeof(GptEntry)) /* 16384 */
 #define PARTITION_ENTRIES_SIZE TOTAL_ENTRIES_SIZE /* 16384 */
 
 static const Guid guid_zero = {{{0, 0, 0, 0, 0, {0, 0, 0, 0, 0, 0}}}};
@@ -245,7 +246,7 @@ static int ParameterTests(void)
 		{512, DEFAULT_DRIVE_SECTORS, GPT_SUCCESS},
 		{520, DEFAULT_DRIVE_SECTORS, GPT_ERROR_INVALID_SECTOR_SIZE},
 		{512, 0, GPT_ERROR_INVALID_SECTOR_NUMBER},
-		{512, 66, GPT_ERROR_INVALID_SECTOR_NUMBER},
+		{512, 10, GPT_ERROR_INVALID_SECTOR_NUMBER},
 		{512, GPT_PMBR_SECTORS + GPT_HEADER_SECTORS * 2 +
 		 TOTAL_ENTRIES_SIZE / DEFAULT_SECTOR_SIZE * 2, GPT_SUCCESS},
 		{4096, DEFAULT_DRIVE_SECTORS, GPT_ERROR_INVALID_SECTOR_SIZE},
diff --git a/tests/vboot_kernel_tests.c b/tests/vboot_kernel_tests.c
index e19ac114..03e77f98 100644
--- a/tests/vboot_kernel_tests.c
+++ b/tests/vboot_kernel_tests.c
@@ -83,7 +83,7 @@ static void SetupGptHeader(GptHeader *h, int is_secondary)
 
 	/* 16KB: 128 entries of 128 bytes */
 	h->size_of_entry = sizeof(GptEntry);
-	h->number_of_entries = TOTAL_ENTRIES_SIZE / h->size_of_entry;
+	h->number_of_entries = MAX_NUMBER_OF_ENTRIES;
 
 	/* Set LBA pointers for primary or secondary header */
 	if (is_secondary) {
@@ -429,6 +429,8 @@ static void ReadWriteGptTest(void)
 	Memset(g.primary_header, '\0', g.sector_bytes);
 	h = (GptHeader*)g.primary_header;
 	h->entries_lba = 2;
+	h->number_of_entries = MAX_NUMBER_OF_ENTRIES;
+	h->size_of_entry = sizeof(GptEntry);
 	TEST_EQ(WriteAndFreeGptData(handle, &g), 0, "WriteAndFree mod 1");
 	TEST_CALLS("VbExDiskWrite(h, 1, 1)\n"
 		   "VbExDiskWrite(h, 2, 32)\n");
@@ -441,6 +443,8 @@ static void ReadWriteGptTest(void)
 	Memset(g.primary_header, '\0', g.sector_bytes);
 	h = (GptHeader*)g.primary_header;
 	h->entries_lba = 2;
+	h->number_of_entries = MAX_NUMBER_OF_ENTRIES;
+	h->size_of_entry = sizeof(GptEntry);
 	h = (GptHeader*)g.secondary_header;
 	h->entries_lba = 991;
 	TEST_EQ(WriteAndFreeGptData(handle, &g), 0, "WriteAndFree mod all");