Two changes to vm_fault_populate():

Simplify the logic for clipping the range returned by the pager to fit
within the map entry.

Use atop() rather than OFF_TO_IDX() on addresses.

Reviewed by:	kib
MFC after:	1 week
This commit is contained in:
Alan Cox 2017-03-19 19:52:47 +00:00
parent 08826086fe
commit 8956418832

View File

@ -352,8 +352,7 @@ vm_fault_populate(struct faultstate *fs, vm_offset_t vaddr, vm_prot_t prot,
MPASS(fs->lookup_still_valid);
pager_first = OFF_TO_IDX(fs->entry->offset);
pager_last = OFF_TO_IDX(fs->entry->offset + fs->entry->end -
fs->entry->start) - 1;
pager_last = pager_first + atop(fs->entry->end - fs->entry->start) - 1;
unlock_map(fs);
unlock_vp(fs);
@ -404,18 +403,20 @@ vm_fault_populate(struct faultstate *fs, vm_offset_t vaddr, vm_prot_t prot,
* In case the pager expanded the range, clip it to fit into
* the map entry.
*/
map_first = MAX(OFF_TO_IDX(fs->entry->offset), pager_first);
if (map_first > pager_first)
map_first = OFF_TO_IDX(fs->entry->offset);
if (map_first > pager_first) {
vm_fault_populate_cleanup(fs->first_object, pager_first,
map_first - 1);
map_last = MIN(OFF_TO_IDX(fs->entry->end - fs->entry->start +
fs->entry->offset) - 1, pager_last);
if (map_last < pager_last)
pager_first = map_first;
}
map_last = map_first + atop(fs->entry->end - fs->entry->start) - 1;
if (map_last < pager_last) {
vm_fault_populate_cleanup(fs->first_object, map_last + 1,
pager_last);
for (pidx = map_first, m = vm_page_lookup(fs->first_object, pidx);
pidx <= map_last; pidx++, m = vm_page_next(m)) {
pager_last = map_last;
}
for (pidx = pager_first, m = vm_page_lookup(fs->first_object, pidx);
pidx <= pager_last; pidx++, m = vm_page_next(m)) {
vm_fault_populate_check_page(m);
vm_fault_dirty(fs->entry, m, prot, fault_type, fault_flags,
true);