kern

annotate src/vm-asm.S @ 73:b4b7198986a6

fixed a potential null dereference when deleting a bug in the redblack tree
author John Tsiombikas <nuclear@member.fsf.org>
date Sat, 15 Oct 2011 08:06:10 +0300
parents 387078ef5c0d
children
rev   line source
nuclear@17 1 .text
nuclear@17 2 /* enable_paging(void)
nuclear@26 3 * sets bit 31 of cr0 which enables page translation */
nuclear@17 4 .globl enable_paging
nuclear@17 5 enable_paging:
nuclear@17 6 movl %cr0, %eax
nuclear@17 7 orl $0x80000000, %eax
nuclear@17 8 movl %eax, %cr0
nuclear@17 9 ret
nuclear@17 10
nuclear@23 11 /* disable_paging(void)
nuclear@26 12 * clears bit 31 of cr0 which disables page translation */
nuclear@23 13 .globl disable_paging
nuclear@23 14 disable_paging:
nuclear@23 15 movl %cr0, %eax
nuclear@23 16 andl $0x7fffffff, %eax
nuclear@23 17 movl %eax, %cr0
nuclear@23 18 ret
nuclear@23 19
nuclear@26 20 /* get_paging_status(void)
nuclear@26 21 * returns 0 if paging is disabled or 1 if it's enabled */
nuclear@23 22 .globl get_paging_status
nuclear@23 23 get_paging_status:
nuclear@23 24 movl %cr0, %eax
nuclear@23 25 shr $31, %eax
nuclear@23 26 ret
nuclear@23 27
nuclear@17 28 /* set_pgdir_addr(uint32_t addr)
nuclear@17 29 * sets the address of the page directory by writing to cr3, which
nuclear@17 30 * also results in a TLB flush. */
nuclear@17 31 .globl set_pgdir_addr
nuclear@17 32 set_pgdir_addr:
nuclear@17 33 movl 4(%esp), %eax
nuclear@17 34 movl %eax, %cr3
nuclear@17 35 ret
nuclear@17 36
nuclear@55 37 /* get_pgdir_addr(void)
nuclear@55 38 * returns the physical address of the page table directory (cr3) */
nuclear@55 39 .globl get_pgdir_addr
nuclear@55 40 get_pgdir_addr:
nuclear@55 41 movl %cr3, %eax
nuclear@55 42 ret
nuclear@55 43
nuclear@23 44 /* flush_tlb(void)
nuclear@23 45 * invalidates the whole TLB. entries for pages marked as global
nuclear@23 46 * are unaffected */
nuclear@23 47 .globl flush_tlb
nuclear@23 48 flush_tlb:
nuclear@23 49 movl %cr3, %eax
nuclear@23 50 movl %eax, %cr3
nuclear@23 51 ret
nuclear@23 52
nuclear@23 53 /* flush_tlb_addr(uint32_t addr)
nuclear@23 54 * flushes the TLB entry for the page containing a particular
nuclear@23 55 * virtual address */
nuclear@23 56 .globl flush_tlb_addr
nuclear@23 57 flush_tlb_addr:
nuclear@23 58 movl 4(%esp), %eax
nuclear@23 59 invlpg (%eax)
nuclear@23 60 ret
nuclear@23 61
nuclear@17 62 /* get_fault_addr(void)
nuclear@17 63 * returns the contents of control register 2, which provides
nuclear@17 64 * the faulting address during a page fault exception
nuclear@17 65 */
nuclear@17 66 .globl get_fault_addr
nuclear@17 67 get_fault_addr:
nuclear@17 68 movl %cr2, %eax
nuclear@17 69 ret