| 986,7 → 986,17 |
|---|
| mutex_lock(&AS->lock); |
| ipl = interrupts_disable(); |
| area = find_area_and_lock(AS, page); |
| if (area->backend != &anon_backend || area->sh_info != NULL) { |
| mutex_unlock(&area->lock); |
| mutex_unlock(&AS->lock); |
| interrupts_restore(ipl); |
| |
| rc = as_area_make_writeable(area->base); |
| if (rc != 0) return rc; |
| |
| goto restart; |
| } |
| |
| pte = page_mapping_find(AS, page); |
| if (! (pte && PTE_VALID(pte) && PTE_PRESENT(pte)) ) { |
| mutex_unlock(&area->lock); |
| 1033,6 → 1043,123 |
|---|
| return EOK; |
| } |
| |
| /** Make sure area is private and anonymous. |
| * |
| * Not atomic atm. |
| * @param address Virtual address in AS. |
| */ |
| int as_area_make_writeable(uintptr_t address) |
| { |
| ipl_t ipl; |
| as_area_t *area; |
| uintptr_t base, page; |
| uintptr_t old_frame, frame; |
| size_t size; |
| int flags; |
| int page_flags; |
| pte_t *pte; |
| int rc; |
| uintptr_t *pagemap; |
| |
| ipl = interrupts_disable(); |
| mutex_lock(&AS->lock); |
| area = find_area_and_lock(AS, address); |
| if (!area) { |
| /* |
| * Could not find the address space area. |
| */ |
| mutex_unlock(&AS->lock); |
| interrupts_restore(ipl); |
| return ENOENT; |
| } |
| |
| if (area->backend == &anon_backend && !area->sh_info) { |
| /* Nothing to do */ |
| mutex_unlock(&area->lock); |
| mutex_unlock(&AS->lock); |
| interrupts_restore(ipl); |
| return EOK; |
| } |
| |
| base = area->base; |
| size = area->pages * PAGE_SIZE; |
| flags = area->flags; |
| page_flags = as_area_get_flags(area); |
| |
| pagemap = malloc(area->pages * sizeof(uintptr_t), 0); |
| page_table_lock(AS, false); |
| |
| for (page = base; page < base + size; page += PAGE_SIZE) { |
| pte = page_mapping_find(AS, page); |
| if (!pte || !PTE_PRESENT(pte) || !PTE_READABLE(pte)) { |
| /* Fetch the missing page */ |
| if (!area->backend || !area->backend->page_fault) { |
| page_table_unlock(AS, false); |
| mutex_unlock(&area->lock); |
| mutex_unlock(&AS->lock); |
| interrupts_restore(ipl); |
| return EINVAL; |
| } |
| if (area->backend->page_fault(area, page, PF_ACCESS_READ) != AS_PF_OK) { |
| page_table_unlock(AS, false); |
| mutex_unlock(&area->lock); |
| mutex_unlock(&AS->lock); |
| interrupts_restore(ipl); |
| return EINVAL; |
| } |
| } |
| ASSERT(PTE_VALID(pte)); |
| |
| old_frame = PTE_GET_FRAME(pte); |
| |
| frame = (uintptr_t)frame_alloc(ONE_FRAME, 0); |
| memcpy((void *) PA2KA(frame), (void *)PA2KA(old_frame), |
| FRAME_SIZE); |
| |
| pagemap[(page - base) / PAGE_SIZE] = frame; |
| } |
| |
| page_table_unlock(AS, false); |
| mutex_unlock(&area->lock); |
| mutex_unlock(&AS->lock); |
| interrupts_restore(ipl); |
| |
| rc = as_area_destroy(AS, address); |
| if (rc < 0) { |
| free(pagemap); |
| return rc; |
| } |
| |
| area = as_area_create(AS, flags, size, base, AS_AREA_ATTR_PARTIAL, |
| &anon_backend, NULL); |
| if (area == NULL) { |
| free(pagemap); |
| return rc; |
| } |
| |
| mutex_lock(&AS->lock); |
| mutex_lock(&area->lock); |
| page_table_lock(AS, false); |
| for (page = base; page < base + size; page += PAGE_SIZE) { |
| frame = pagemap[(page - base) / PAGE_SIZE]; |
| |
| page_mapping_insert(AS, page, frame, page_flags); |
| if (!used_space_insert(area, page, 1)) |
| panic("Could not insert used space.\n"); |
| } |
| |
| page_table_unlock(AS, false); |
| |
| area->attributes &= ~AS_AREA_ATTR_PARTIAL; |
| |
| mutex_unlock(&area->lock); |
| mutex_unlock(&AS->lock); |
| |
| free(pagemap); |
| |
| return EOK; |
| } |
| |
| /** Convert address space area flags to page flags. |
| * |
| * @param aflags Flags of some address space area. |