diff options
| -rw-r--r-- | kernel/include/mm/virtual_mm.h | 35 | ||||
| -rw-r--r-- | kernel/mm/virtual_mm/virtual_mm.c | 102 |
2 files changed, 11 insertions, 126 deletions
diff --git a/kernel/include/mm/virtual_mm.h b/kernel/include/mm/virtual_mm.h index f605cc7..4873a30 100644 --- a/kernel/include/mm/virtual_mm.h +++ b/kernel/include/mm/virtual_mm.h @@ -64,31 +64,6 @@ #define ADD_ATTRIB(entry, attribute) (*entry |= (attribute)) /* - * Given a page table entry, it sets the frame to a newly allocated address, - * and sets the present bit to false. - */ -bool virtual_mm_allocate_page(uint32_t *pt_entry); - -/* - * Given a page table entry, it sets the entry to 0 (therefore zero-ing the - * frame and present bit). - */ -bool virtual_mm_free_page(uint32_t *pt_entry); - -/* - * Given a page table and virtual address, it returns a pointer to the page - * table entry referenced by the virtual address. - */ -uint32_t *virtual_mm_lookup_table(uint32_t *page_table, uint32_t virtual_addr); - -/* - * Given a page directory and virtual address, it returns a pointer to the page - * directory entry referenced by the virtual address. - */ -uint32_t *virtual_mm_lookup_directory(uint32_t *page_directory, - uint32_t virtual_addr); - -/* * Loads a given page directory into CR0 */ void virtual_mm_load_page_directory(uint32_t *page_directory); @@ -99,16 +74,6 @@ void virtual_mm_load_page_directory(uint32_t *page_directory); bool virtual_mm_switch_page_directory(uint32_t *page_directory); /* - * Flushes the given TLB entry - */ -void virtual_mm_flush_tlb_entry(uint32_t *virtual_addr); - -/* - * Map a given physical address to a virtual address - */ -bool virtual_mm_map_page(uint32_t *physical_addr, uint32_t *virtual_addr); - -/* * Initialize the virtual memory manager */ void virtual_mm_initialize(void); diff --git a/kernel/mm/virtual_mm/virtual_mm.c b/kernel/mm/virtual_mm/virtual_mm.c index 7007350..d8d3d70 100644 --- a/kernel/mm/virtual_mm/virtual_mm.c +++ b/kernel/mm/virtual_mm/virtual_mm.c @@ -30,53 +30,10 @@ extern uint32_t kernel_end; uint32_t *current_page_directory = 0; -bool -virtual_mm_allocate_page(uint32_t *pt_entry) -{ - void *ptr = physical_mm_allocate_block(); - if (!ptr) - return false; - - ADD_ATTRIB(pt_entry, SET_PTE_FRAME((uint32_t) ptr)); - ADD_ATTRIB(pt_entry, SET_PTE_PRESENT(1)); - - return true; -} - -bool -virtual_mm_free_page(uint32_t *pt_entry) -{ - void *ptr = (void *) GET_PTE_FRAME(pt_entry); - if (ptr) - physical_mm_free_block(ptr); - - *pt_entry = 0; - - return true; -} - -ALWAYS_INLINE uint32_t * -virtual_mm_lookup_table(uint32_t *page_table, uint32_t virtual_addr) -{ - if (page_table) - return &page_table[PAGE_TABLE_INDEX(virtual_addr)]; - - return NULL; -} - -ALWAYS_INLINE uint32_t * -virtual_mm_lookup_directory(uint32_t *page_directory, uint32_t virtual_addr) -{ - if (page_directory) - return &page_directory[PAGE_DIRECTORY_INDEX(virtual_addr)]; - - return NULL; -} - ALWAYS_INLINE void virtual_mm_load_page_directory(uint32_t *page_directory) { - __asm__("movl %0, %%cr3" ::"r"(page_directory)); + __asm__("movl %0, %%eax" ::"r"(page_directory)); } bool @@ -90,43 +47,6 @@ virtual_mm_switch_page_directory(uint32_t *page_directory) return true; } -/* TODO: I have absolutely _no_ idea if this works */ -void -virtual_mm_flush_tlb_entry(uint32_t *virtual_addr) -{ - __asm__("cli;" - "invlpg (%0);" - "sti" ::"r"(virtual_addr)); -} - -bool -virtual_mm_map_page(uint32_t *physical_addr, uint32_t *virtual_addr) -{ - uint32_t *pd_entry - = ¤t_page_directory[PAGE_DIRECTORY_INDEX((uint32_t) virtual_addr)]; - - /* If the page directory entry isn't present */ - if (!PTE_IS_PRESENT(*pd_entry)) { - uint32_t *page_table = physical_mm_allocate_block(); - if (!page_table) - return false; - - *pd_entry = 0; - ADD_ATTRIB(pd_entry, SET_PDE_PRESENT(1)); - ADD_ATTRIB(pd_entry, SET_PDE_WRITABLE(1)); - ADD_ATTRIB(pd_entry, SET_PDE_FRAME((uint32_t) page_table)); - } - - uint32_t *page_table = (uint32_t *) GET_PDE_FRAME(pd_entry); - uint32_t *pt_entry = &page_table[PAGE_TABLE_INDEX((uint32_t) virtual_addr)]; - *pt_entry = 0; - - ADD_ATTRIB(pt_entry, SET_PTE_PRESENT(1)); - ADD_ATTRIB(pt_entry, SET_PTE_FRAME((uint32_t) physical_addr)); - - return true; -} - ALWAYS_INLINE static void virtual_mm_enable_paging(void) { @@ -149,15 +69,14 @@ virtual_mm_initialize(void) /* Identity map the first 4MiB (maps 4KiB 1024 times) */ for (uint32_t i = 0, physical_addr = 0, virtual_addr = 0; i < 1024; i++, physical_addr += 4096, virtual_addr += 4096) { - uint32_t page = 0; - ADD_ATTRIB(&page, SET_PTE_PRESENT(1)); - ADD_ATTRIB(&page, SET_PTE_FRAME(physical_addr)); + uint32_t pt_entry = 0; + ADD_ATTRIB(&pt_entry, SET_PTE_PRESENT(1)); + ADD_ATTRIB(&pt_entry, SET_PTE_WRITABLE(1)); + ADD_ATTRIB(&pt_entry, SET_PTE_FRAME(physical_addr)); - table[PAGE_TABLE_INDEX(virtual_addr)] = page; + table[PAGE_TABLE_INDEX(virtual_addr)] = pt_entry; } - printk("\n\ndebug", - "Table: 0x%x", - GET_PTE_FRAME(&table[PAGE_TABLE_INDEX(0x2000)])); + printk("debug", "Page table is at: 0x%x", table); uint32_t *page_directory = physical_mm_allocate_block(); if (!page_directory) @@ -166,13 +85,14 @@ virtual_mm_initialize(void) for (uint32_t i = 0; i < 1024; i++) page_directory[i] = 0; - current_page_directory = page_directory; - uint32_t *pd_entry = &page_directory[PAGE_DIRECTORY_INDEX(0)]; ADD_ATTRIB(pd_entry, SET_PDE_PRESENT(1)); ADD_ATTRIB(pd_entry, SET_PDE_WRITABLE(1)); ADD_ATTRIB(pd_entry, SET_PDE_FRAME((uint32_t) table)); - virtual_mm_switch_page_directory(current_page_directory); + printk("debug", "Page directory is at: 0x%x", page_directory); + printk("debug", "pd_entry: 0x%x", pd_entry); + + virtual_mm_switch_page_directory(page_directory); virtual_mm_enable_paging(); } |