kernel/arm/paging: zero out the bottom portion of the new pgdir

Change-Id: I899f288f451dd4c413403cd0e14a855f68355050 Reviewed-on: https://review.haiku-os.org/c/haiku/+/4866 Tested-by: Commit checker robot <[email protected]> Reviewed-by: Fredrik Holmqvist <[email protected]> Reviewed-by: Alex von Gluck IV <[email protected]>
2022-01-23 08:50:46 +00:00
parent 933430df22
commit b57ffe4006
2 changed files with 3 additions and 4 deletions
@@ -65,11 +65,10 @@ ARMPagingStructures32Bit::Init(page_directory_entry* virtualPageDir,
 	pgdir_virt = virtualPageDir;
 	pgdir_phys = physicalPageDir;

-#if 0 // IRA: handle UART better; identity map of DEVICE_BASE from loader gets wiped here
 	// zero out the bottom portion of the new pgdir
 	memset(pgdir_virt + FIRST_USER_PGDIR_ENT, 0,
 		NUM_USER_PGDIR_ENTS * sizeof(page_directory_entry));
-#endif
+
 	// insert this new map into the map list
 	{
 		int state = disable_interrupts();
@@ -21,12 +21,12 @@

 #define FIRST_USER_PGDIR_ENT    (VADDR_TO_PDENT(USER_BASE))
 #define NUM_USER_PGDIR_ENTS     (VADDR_TO_PDENT(ROUNDUP(USER_SIZE, \
-									B_PAGE_SIZE * 1024)))
+					B_PAGE_SIZE * ARM_MMU_L2_COARSE_ENTRY_COUNT)))
 #define FIRST_KERNEL_PGDIR_ENT  (VADDR_TO_PDENT(KERNEL_BASE))
 #define NUM_KERNEL_PGDIR_ENTS   (VADDR_TO_PDENT(KERNEL_SIZE))


-static const size_t kPageTableAlignment = 1024 * B_PAGE_SIZE;
+static const size_t kPageTableAlignment = ARM_MMU_L2_COARSE_ENTRY_COUNT * B_PAGE_SIZE;


 typedef uint32 page_table_entry;