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Kernel: Add PageTable::Flags::CacheDisable

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Also fix multiple places where we were using uint8_t as page table
flags instead of PageTable::flags_t which we promoted to uint16_t
while back.
This commit is contained in:
Bananymous
2023-08-06 23:59:30 +03:00
parent d8a9d4a24e
commit 008c777a9f
7 changed files with 36 additions and 18 deletions
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25
kernel/arch/x86_64/PageTable.cpp
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@@ -48,7 +48,22 @@ namespace Kernel
static inline PageTable::flags_t parse_flags(uint64_t entry)
{
return (s_has_nxe && !(entry & (1ull << 63)) ? PageTable::Flags::Execute : 0) | (entry & 0b100000111);
using Flags = PageTable::Flags;
PageTable::flags_t result = 0;
if (s_has_nxe && !(entry & (1ull << 63)))
result |= Flags::Execute;
if (entry & Flags::Reserved)
result |= Flags::Reserved;
if (entry & Flags::CacheDisable)
result |= Flags::CacheDisable;
if (entry & Flags::UserSupervisor)
result |= Flags::UserSupervisor;
if (entry & Flags::ReadWrite)
result |= Flags::ReadWrite;
if (entry & Flags::Present)
result |= Flags::Present;
return result;
}
void PageTable::initialize()
@@ -258,13 +273,15 @@ namespace Kernel
uint64_t pte = (uc_vaddr >> 12) & 0x1FF;
uint64_t extra_flags = 0;
if (s_has_pge && pml4e == 511) // Map kernel memory as global
extra_flags |= 1ull << 8;
if (s_has_nxe && !(flags & Flags::Execute))
extra_flags |= 1ull << 63;
if (s_has_pge && pml4e == 511)
extra_flags |= 1ull << 8;
if (flags & Flags::Reserved)
extra_flags |= Flags::Reserved;
if (flags & Flags::CacheDisable)
extra_flags |= Flags::CacheDisable;
// NOTE: we add present here, since it has to be available in higher level structures
flags_t uwr_flags = (flags & (Flags::UserSupervisor | Flags::ReadWrite)) | Flags::Present;