diff options
Diffstat (limited to 'kernel/features/mm.c')
| -rw-r--r-- | kernel/features/mm.c | 28 |
1 files changed, 19 insertions, 9 deletions
diff --git a/kernel/features/mm.c b/kernel/features/mm.c index 064f78c..3be798a 100644 --- a/kernel/features/mm.c +++ b/kernel/features/mm.c @@ -25,14 +25,14 @@ static void paging_switch_dir(u32 dir) extern void paging_invalidate_tlb(void); -/*void paging_disable(void) +void paging_disable(void) { cr0_set(cr0_get() | 0x7fffffff); -}*/ +} void paging_enable(void) { - cr0_set(cr0_get() | 0x80000000); + cr0_set(cr0_get() | 0x80010000); } void page_fault_handler(struct regs *r) @@ -224,7 +224,7 @@ void virtual_map(struct page_dir *dir, struct memory_range prange, u32 vaddr, u3 u32 pti = PTI(vaddr + offset); union page_table_entry *table_entry = &table->entries[pti]; table_entry->bits.present = 1; - table_entry->bits.writable = 1; + table_entry->bits.writable = !(flags & MEMORY_READONLY); table_entry->bits.user = flags & MEMORY_USER; table_entry->bits.address = (prange.base + offset) >> 12; } @@ -561,11 +561,20 @@ struct memory_range memory_range_around(u32 base, u32 size) return memory_range(base, size); } -extern u32 kernel_start; -extern u32 kernel_end; -static struct memory_range kernel_memory_range(void) +extern u32 kernel_rw_start; +extern u32 kernel_rw_end; +static struct memory_range kernel_rw_memory_range(void) +{ + return memory_range_around((u32)&kernel_rw_start, + (u32)&kernel_rw_end - (u32)&kernel_rw_start); +} + +extern u32 kernel_ro_start; +extern u32 kernel_ro_end; +static struct memory_range kernel_ro_memory_range(void) { - return memory_range_around((u32)&kernel_start, (u32)&kernel_end - (u32)&kernel_start); + return memory_range_around((u32)&kernel_ro_start, + (u32)&kernel_ro_end - (u32)&kernel_ro_start); } void memory_install(struct mem_info *mem_info, struct vid_info *vid_info) @@ -600,7 +609,8 @@ void memory_install(struct mem_info *mem_info, struct vid_info *vid_info) printf("Detected memory: %dKiB (%dMiB)\n", memory_total >> 10, memory_total >> 20); // Map kernel - memory_map_identity(&kernel_dir, kernel_memory_range(), MEMORY_NONE); + memory_map_identity(&kernel_dir, kernel_ro_memory_range(), MEMORY_READONLY); + memory_map_identity(&kernel_dir, kernel_rw_memory_range(), MEMORY_NONE); // Map kernel stack memory_map_identity(&kernel_dir, memory_range_around(STACK_START - STACK_SIZE, STACK_SIZE), |