diff options
Diffstat (limited to 'sys/kern')
| -rw-r--r-- | sys/kern/subr_trap.c | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/sys/kern/subr_trap.c b/sys/kern/subr_trap.c index 15a2684..7e5d5c4 100644 --- a/sys/kern/subr_trap.c +++ b/sys/kern/subr_trap.c @@ -34,7 +34,7 @@ * SUCH DAMAGE. * * from: @(#)trap.c 7.4 (Berkeley) 5/13/91 - * $Id: trap.c,v 1.13 1994/01/03 07:55:24 davidg Exp $ + * $Id: trap.c,v 1.14 1994/01/14 16:23:41 davidg Exp $ */ /* @@ -390,10 +390,10 @@ skiptoswitch: /* check if page table is mapped, if not, fault it first */ #define pde_v(v) (PTD[((v)>>PD_SHIFT)&1023].pd_v) { - vm_offset_t v = trunc_page(vtopte(va)); if (map != kernel_map) { vm_offset_t pa; + vm_offset_t v = (vm_offset_t) vtopte(va); /* Fault the pte only if needed: */ *(volatile char *)v += 0; @@ -401,16 +401,21 @@ skiptoswitch: /* Get the physical address: */ pa = pmap_extract(vm_map_pmap(map), v); - /* And wire the page at system vm level: */ + /* And wire the pte page at system vm level: */ vm_page_wire(PHYS_TO_VM_PAGE(pa)); /* Fault in the user page: */ rv = vm_fault(map, va, ftype, FALSE); - /* Unwire the pte page */ + /* Unwire the pte page: */ vm_page_unwire(PHYS_TO_VM_PAGE(pa)); } else { + /* + * Since we know that kernel virtual address addresses + * always have pte pages mapped, we just have to fault + * the page. + */ rv = vm_fault(map, va, ftype, FALSE); } @@ -606,10 +611,19 @@ int trapwrite(addr) { vm_offset_t v; v = trunc_page(vtopte(va)); + /* + * wire the pte page + */ if (va < USRSTACK) { vm_map_pageable(&vm->vm_map, v, round_page(v+1), FALSE); } + /* + * fault the data page + */ rv = vm_fault(&vm->vm_map, va, VM_PROT_READ|VM_PROT_WRITE, FALSE); + /* + * unwire the pte page + */ if (va < USRSTACK) { vm_map_pageable(&vm->vm_map, v, round_page(v+1), TRUE); } |
