Implement pmap_unwire(). See r268327 for the motivation behind this change.

This commit is contained in:
Alan Cox 2014-07-16 21:06:43 +00:00
parent cfe17cfcac
commit 526ed91414
2 changed files with 119 additions and 0 deletions

View File

@ -3302,6 +3302,79 @@ pmap_change_wiring(pmap_t pmap, vm_offset_t va, boolean_t wired)
PMAP_UNLOCK(pmap);
}
/*
* Clear the wired attribute from the mappings for the specified range of
* addresses in the given pmap. Every valid mapping within that range
* must have the wired attribute set. In contrast, invalid mappings
* cannot have the wired attribute set, so they are ignored.
*
* XXX Wired mappings of unmanaged pages cannot be counted by this pmap
* implementation.
*/
void
pmap_unwire(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
{
struct l2_bucket *l2b;
struct md_page *pvh;
pd_entry_t l1pd;
pt_entry_t *ptep, pte;
pv_entry_t pv;
vm_offset_t next_bucket;
vm_paddr_t pa;
vm_page_t m;
rw_wlock(&pvh_global_lock);
PMAP_LOCK(pmap);
while (sva < eva) {
next_bucket = L2_NEXT_BUCKET(sva);
l1pd = pmap->pm_l1->l1_kva[L1_IDX(sva)];
if ((l1pd & L1_TYPE_MASK) == L1_S_PROTO) {
pa = l1pd & L1_S_FRAME;
m = PHYS_TO_VM_PAGE(pa);
KASSERT(m != NULL && (m->oflags & VPO_UNMANAGED) == 0,
("pmap_unwire: unmanaged 1mpage %p", m));
pvh = pa_to_pvh(pa);
pv = pmap_find_pv(pvh, pmap, trunc_1mpage(sva));
if ((pv->pv_flags & PVF_WIRED) == 0)
panic("pmap_unwire: pv %p isn't wired", pv);
/*
* Are we unwiring the entire large page? If not,
* demote the mapping and fall through.
*/
if (sva + L1_S_SIZE == next_bucket &&
eva >= next_bucket) {
pv->pv_flags &= ~PVF_WIRED;
pmap->pm_stats.wired_count -= L2_PTE_NUM_TOTAL;
sva = next_bucket;
continue;
} else if (!pmap_demote_section(pmap, sva))
panic("pmap_unwire: demotion failed");
}
if (next_bucket > eva)
next_bucket = eva;
l2b = pmap_get_l2_bucket(pmap, sva);
if (l2b == NULL) {
sva = next_bucket;
continue;
}
for (ptep = &l2b->l2b_kva[l2pte_index(sva)]; sva < next_bucket;
sva += PAGE_SIZE, ptep++) {
if ((pte = *ptep) == 0 ||
(m = PHYS_TO_VM_PAGE(l2pte_pa(pte))) == NULL ||
(m->oflags & VPO_UNMANAGED) != 0)
continue;
pv = pmap_find_pv(&m->md, pmap, sva);
if ((pv->pv_flags & PVF_WIRED) == 0)
panic("pmap_unwire: pv %p isn't wired", pv);
pv->pv_flags &= ~PVF_WIRED;
pmap->pm_stats.wired_count--;
}
}
rw_wunlock(&pvh_global_lock);
PMAP_UNLOCK(pmap);
}
/*
* Copy the range specified by src_addr/len

View File

@ -3570,6 +3570,52 @@ pmap_change_wiring(pmap_t pmap, vm_offset_t va, boolean_t wired)
PMAP_UNLOCK(pmap);
}
/*
* Clear the wired attribute from the mappings for the specified range of
* addresses in the given pmap. Every valid mapping within that range
* must have the wired attribute set. In contrast, invalid mappings
* cannot have the wired attribute set, so they are ignored.
*
* XXX Wired mappings of unmanaged pages cannot be counted by this pmap
* implementation.
*/
void
pmap_unwire(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
{
struct l2_bucket *l2b;
pt_entry_t *ptep, pte;
pv_entry_t pv;
vm_offset_t next_bucket;
vm_page_t m;
rw_wlock(&pvh_global_lock);
PMAP_LOCK(pmap);
while (sva < eva) {
next_bucket = L2_NEXT_BUCKET(sva);
if (next_bucket > eva)
next_bucket = eva;
l2b = pmap_get_l2_bucket(pmap, sva);
if (l2b == NULL) {
sva = next_bucket;
continue;
}
for (ptep = &l2b->l2b_kva[l2pte_index(sva)]; sva < next_bucket;
sva += PAGE_SIZE, ptep++) {
if ((pte = *ptep) == 0 ||
(m = PHYS_TO_VM_PAGE(l2pte_pa(pte))) == NULL ||
(m->oflags & VPO_UNMANAGED) != 0)
continue;
pv = pmap_find_pv(m, pmap, sva);
if ((pv->pv_flags & PVF_WIRED) == 0)
panic("pmap_unwire: pv %p isn't wired", pv);
pv->pv_flags &= ~PVF_WIRED;
pmap->pm_stats.wired_count--;
}
}
rw_wunlock(&pvh_global_lock);
PMAP_UNLOCK(pmap);
}
/*
* Copy the range specified by src_addr/len