kernel/arm/paging: implement Modified Flag

* Introduce SWDBM flag similarly to the arm64 port
* Reuse TEX[2] for SWDBM flag which should be availble
  to be used by the operating system if TEX remap
  is enabled.
* Introduce SetAndClearPageTableEntryFlags for updating
  accessed and modified flags atomically
* Startup sequence is handled similarly to accessed flag, i.e.
  set Modified flag in initially mapped pages in bootloader and early map.
* Once the kernel initialization has progressed enough,
  pages are mapped as read-only and modified flag handling is done
  in the page fault handler.

Change-Id: I8f761e2c6325d1b91481abd569d5e8befded0761
Reviewed-on: https://review.haiku-os.org/c/haiku/+/6518
Tested-by: Commit checker robot <[email protected]>
Reviewed-by: Adrien Destugues <[email protected]>

This commit is contained in:

David Karoly

2023-06-18 11:18:24 +00:00

committed by

Adrien Destugues

parent 73c451087f

commit b799d160f2

7 changed files with 83 additions and 35 deletions

									
										headers/private/system/arch/arm/arch_cpu_defs.h
									
		+3
		
												View File
												
				@@ -34,4 +34,7 @@

				#define FSR_FS_PERMISSION_FAULT_L1	0x0d

				#define FSR_FS_PERMISSION_FAULT_L2	0x0f

				#define FSR_FS_MASK			0x040f

				#define FSR_LPAE_MASK		0x0200

				#endif	/* _SYSTEM_ARCH_ARM_DEFS_H */