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- Update the vm_object locking in vm_map_insert().

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alc 2003-04-20 21:56:40 +00:00
parent b634e61b93
commit fb6235893f
1 changed files with 13 additions and 8 deletions
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21
sys/vm/vm_map.c
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@ -811,17 +811,22 @@ vm_map_insert(vm_map_t map, vm_object_t object, vm_ooffset_t offset,
if (cow & MAP_DISABLE_COREDUMP)
protoeflags |= MAP_ENTRY_NOCOREDUMP;
if (object) {
if (object != NULL) {
/*
* When object is non-NULL, it could be shared with another
* process. We have to set or clear OBJ_ONEMAPPING
* appropriately.
* OBJ_ONEMAPPING must be cleared unless this mapping
* is trivially proven to be the only mapping for any
* of the object's pages. (Object granularity
* reference counting is insufficient to recognize
* aliases with precision.)
*/
vm_object_lock(object);
if ((object->ref_count > 1) || (object->shadow_count != 0)) {
if (object != kmem_object)
mtx_lock(&Giant);
VM_OBJECT_LOCK(object);
if (object->ref_count > 1 || object->shadow_count != 0)
vm_object_clear_flag(object, OBJ_ONEMAPPING);
}
vm_object_unlock(object);
VM_OBJECT_UNLOCK(object);
if (object != kmem_object)
mtx_unlock(&Giant);
}
else if ((prev_entry != &map->header) &&
(prev_entry->eflags == protoeflags) &&