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- Lock the pte object when performing vm_page_grab().

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- Insure that the page table page is zero filled before adding it
   to the page table.
This commit is contained in:
Alan Cox 2003-08-20 05:09:55 +00:00
parent 6d2a9bd669
commit 2b12cfb461
1 changed files with 9 additions and 6 deletions
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15
sys/amd64/amd64/pmap.c
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@ -1016,12 +1016,14 @@ pmap_pinit(pmap)
/*
* allocate the page directory page
*/
VM_OBJECT_LOCK(pmap->pm_pteobj);
pml4pg = vm_page_grab(pmap->pm_pteobj, NUPDE + NUPDPE + NUPML4E,
VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED | VM_ALLOC_ZERO);
vm_page_lock_queues();
vm_page_flag_clear(pml4pg, PG_BUSY);
pml4pg->valid = VM_PAGE_BITS_ALL;
vm_page_unlock_queues();
VM_OBJECT_UNLOCK(pmap->pm_pteobj);
pmap->pm_pml4 = (pml4_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(pml4pg));
@ -1067,12 +1069,17 @@ _pmap_allocpte(pmap, ptepindex)
vm_pindex_t ptepindex;
{
vm_page_t m, pdppg, pdpg;
int is_object_locked;
/*
* Find or fabricate a new pagetable page
*/
if (!(is_object_locked = VM_OBJECT_LOCKED(pmap->pm_pteobj)))
VM_OBJECT_LOCK(pmap->pm_pteobj);
m = vm_page_grab(pmap->pm_pteobj, ptepindex,
VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY);
if ((m->flags & PG_ZERO) == 0)
pmap_zero_page(m);
KASSERT(m->queue == PQ_NONE,
("_pmap_allocpte: %p->queue != PQ_NONE", m));
@ -1161,17 +1168,13 @@ _pmap_allocpte(pmap, ptepindex)
*pd = VM_PAGE_TO_PHYS(m) | PG_U | PG_RW | PG_V | PG_A | PG_M;
}
/*
* Try to use the new mapping, but if we cannot, then
* do it with the routine that maps the page explicitly.
*/
if ((m->flags & PG_ZERO) == 0)
pmap_zero_page(m);
vm_page_lock_queues();
m->valid = VM_PAGE_BITS_ALL;
vm_page_flag_clear(m, PG_ZERO);
vm_page_wakeup(m);
vm_page_unlock_queues();
if (!is_object_locked)
VM_OBJECT_UNLOCK(pmap->pm_pteobj);
return m;
}