void destroy_area(struct vm_address_space *space, struct vm_area *area)
{
struct vm_cache *cache;
unsigned int va;
unsigned int ptentry;
rwlock_lock_write(&space->mut);
cache = area->cache;
// Unmap all pages in this area
for (va = area->low_address; va < area->high_address; va += PAGE_SIZE)
{
ptentry = query_translation_map(space->translation_map, va);
if ((ptentry & PAGE_PRESENT) != 0)
{
VM_DEBUG("destroy_area: decrementing page ref for va %08x pa %08x\n",
va, PAGE_ALIGN(ptentry));
dec_page_ref(pa_to_page(ptentry));
}
}
destroy_vm_area(area);
rwlock_unlock_write(&space->mut);
if (cache)
dec_cache_ref(cache);
}
/**
* @brief This function is not called from anywhere and may be removed.
*/
void neue_wlock(neue_t *neue) {
if (neue) {
rwlock_lock_write(&(neue->lock));
//log_pedantic("%20.li granted write lock", thread_get_thread_id());
}
return;
}
// This area is wired by default and does not take page faults.
// The pages for this area should already have been allocated: this will not
// mark them as such. The area created by this will not be backed by a
// vm_cache or vm_backing_store.
struct vm_area *map_contiguous_memory(struct vm_address_space *space, unsigned int address,
unsigned int size, enum placement place,
const char *name, unsigned int area_flags,
unsigned int phys_addr)
{
struct vm_area *area;
unsigned int page_flags;
unsigned int offset;
area_flags |= AREA_WIRED;
rwlock_lock_write(&space->mut);
area = create_vm_area(&space->area_map, address, size, place, name, area_flags);
if (area == 0)
{
kprintf("create area failed\n");
goto error1;
}
area->cache = 0;
page_flags = PAGE_PRESENT;
// We do not do dirty page tracking on these areas, as this is expected to
// be device memory. Mark pages writable by default if the area is writable.
if ((area_flags & AREA_WRITABLE) != 0)
page_flags |= PAGE_WRITABLE;
if (area->flags & AREA_EXECUTABLE)
page_flags |= PAGE_EXECUTABLE;
if (space == &kernel_address_space)
page_flags |= PAGE_SUPERVISOR | PAGE_GLOBAL;
// Map the pages
for (offset = 0; offset < size; offset += PAGE_SIZE)
{
vm_map_page(space->translation_map, area->low_address + offset,
(phys_addr + offset) | page_flags);
}
error1:
rwlock_unlock_write(&space->mut);
return area;
}
struct vm_area *create_area(struct vm_address_space *space, unsigned int address,
unsigned int size, enum placement place,
const char *name, unsigned int flags,
struct vm_cache *cache, unsigned int cache_offset)
{
struct vm_area *area;
unsigned int fault_addr;
// Anonymous area, create a cache if non is specified.
if (cache == 0)
cache = create_vm_cache(0);
rwlock_lock_write(&space->mut);
area = create_vm_area(&space->area_map, address, size, place, name, flags);
if (area == 0)
{
kprintf("create area failed\n");
goto error1;
}
area->cache = cache;
area->cache_offset = cache_offset;
area->cache_length = size;
if (flags & AREA_WIRED)
{
for (fault_addr = area->low_address; fault_addr < area->high_address;
fault_addr += PAGE_SIZE)
{
if (!soft_fault(space, area, fault_addr, 1))
panic("create_area: soft fault failed");
}
}
error1:
rwlock_unlock_write(&space->mut);
return area;
}