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Calculate the new PTE value in pmap_enter() before acquiring any locks.

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Move an assertion to the beginning of pmap_enter().
This commit is contained in:
alc 2012-09-02 04:39:07 +00:00
parent 2d9c0c0384
commit 9037eaf691
1 changed files with 17 additions and 24 deletions
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41
sys/mips/mips/pmap.c
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@ -1969,14 +1969,24 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_prot_t access, vm_page_t m,
pt_entry_t origpte, newpte;
pv_entry_t pv;
vm_page_t mpte, om;
pt_entry_t rw;
va &= ~PAGE_MASK;
KASSERT(va <= VM_MAX_KERNEL_ADDRESS, ("pmap_enter: toobig"));
KASSERT((m->oflags & VPO_UNMANAGED) != 0 || va < kmi.clean_sva ||
va >= kmi.clean_eva,
("pmap_enter: managed mapping within the clean submap"));
KASSERT((m->oflags & (VPO_UNMANAGED | VPO_BUSY)) != 0,
("pmap_enter: page %p is not busy", m));
pa = VM_PAGE_TO_PHYS(m);
newpte = TLBLO_PA_TO_PFN(pa) | PTE_V;
newpte = TLBLO_PA_TO_PFN(pa) | init_pte_prot(m, access, prot);
if (wired)
newpte |= PTE_W;
if (is_kernel_pmap(pmap))
newpte |= PTE_G;
if (is_cacheable_mem(pa))
newpte |= PTE_C_CACHE;
else
newpte |= PTE_C_UNCACHED;
mpte = NULL;
@ -2031,6 +2041,8 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_prot_t access, vm_page_t m,
if (pte_test(&origpte, PTE_MANAGED)) {
om = m;
newpte |= PTE_MANAGED;
if (!pte_test(&newpte, PTE_RO))
vm_page_aflag_set(m, PGA_WRITEABLE);
}
goto validate;
}
@ -2059,18 +2071,16 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_prot_t access, vm_page_t m,
pmap->pm_stats.resident_count++;
/*
* Enter on the PV list if part of our managed memory. Note that we
* raise IPL while manipulating pv_table since pmap_enter can be
* called at interrupt time.
* Enter on the PV list if part of our managed memory.
*/
if ((m->oflags & VPO_UNMANAGED) == 0) {
KASSERT(va < kmi.clean_sva || va >= kmi.clean_eva,
("pmap_enter: managed mapping within the clean submap"));
if (pv == NULL)
pv = get_pv_entry(pmap, FALSE);
pv->pv_va = va;
TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
newpte |= PTE_MANAGED;
if (!pte_test(&newpte, PTE_RO))
vm_page_aflag_set(m, PGA_WRITEABLE);
} else if (pv != NULL)
free_pv_entry(pmap, pv);
@ -2083,26 +2093,10 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_prot_t access, vm_page_t m,
validate:
if ((access & VM_PROT_WRITE) != 0)
m->md.pv_flags |= PV_TABLE_REF;
rw = init_pte_prot(m, access, prot);
#ifdef PMAP_DEBUG
printf("pmap_enter: va: %p -> pa: %p\n", (void *)va, (void *)pa);
#endif
/*
* Now validate mapping with desired protection/wiring.
*/
newpte |= rw;
if (is_cacheable_mem(pa))
newpte |= PTE_C_CACHE;
else
newpte |= PTE_C_UNCACHED;
if (wired)
newpte |= PTE_W;
if (is_kernel_pmap(pmap))
newpte |= PTE_G;
/*
* if the mapping or permission bits are different, we need to
@ -3248,7 +3242,6 @@ init_pte_prot(vm_page_t m, vm_prot_t access, vm_prot_t prot)
rw = PTE_V | PTE_D;
else
rw = PTE_V;
vm_page_aflag_set(m, PGA_WRITEABLE);
} else
/* Needn't emulate a modified bit for unmanaged pages. */
rw = PTE_V | PTE_D;