int test(lua_State *L) {
void *ptr = lua_newuserdata(L, sizeof(char) * 32);
vm_object_create();
vm_field_set_string("name", "Test");
lua_setmetatable(L, 1);
return 1;
}
/*
* vm_object_copy: clone a vm_object.
*
* Synchronization: None; lpage_copy does the hard stuff.
*/
int
vm_object_copy(struct vm_object *vmo, struct addrspace *newas,
struct vm_object **ret)
{
struct vm_object *newvmo;
struct lpage *newlp, *lp;
unsigned j;
int result;
newvmo = vm_object_create(lpage_array_num(vmo->vmo_lpages));
if (newvmo == NULL) {
return ENOMEM;
}
newvmo->vmo_base = vmo->vmo_base;
newvmo->vmo_lower_redzone = vmo->vmo_lower_redzone;
for (j = 0; j < lpage_array_num(vmo->vmo_lpages); j++) {
lp = lpage_array_get(vmo->vmo_lpages, j);
newlp = lpage_array_get(newvmo->vmo_lpages, j);
/* new guy should be initialized to all zerofill */
KASSERT(newlp == NULL);
if (lp == NULL) {
/* old guy is zerofill too, don't do anything */
continue;
}
result = lpage_copy(lp, &newlp);
if (result) {
goto fail;
}
lpage_array_set(newvmo->vmo_lpages, j, newlp);
}
*ret = newvmo;
return 0;
fail:
vm_object_destroy(newas, newvmo);
return result;
}
/*
* Set up a segment at virtual address VADDR of size MEMSIZE. The
* segment in memory extends from VADDR up to (but not including)
* VADDR+MEMSIZE.
*
* The READABLE, WRITEABLE, and EXECUTABLE flags are set if read,
* write, or execute permission should be set on the segment. At the
* moment, these are ignored.
*
* Does not allow overlapping regions.
*/
int
as_define_region(struct addrspace *as, vaddr_t vaddr, size_t sz,
size_t lower_redzone,
int readable, int writeable, int executable)
{
struct vm_object *vmo;
int i, result;
vaddr_t check_vaddr; /* vaddr to use for overlap check */
(void)readable;
(void)writeable; // XYZ
(void)executable;
/* base address must be aligned */
assert((vaddr & PAGE_FRAME)==vaddr);
/* redzone must be aligned */
assert((lower_redzone & PAGE_FRAME)==lower_redzone);
/* redzone must fit */
assert(vaddr >= lower_redzone);
check_vaddr = vaddr - lower_redzone;
/* size may not be */
sz = ROUNDUP(sz, PAGE_SIZE);
/*
* Check for overlaps.
*/
for (i = 0; i < array_getnum(as->as_objects); i++) {
vaddr_t bot, top;
vmo = array_getguy(as->as_objects, i);
assert(vmo != NULL);
bot = vmo->vmo_base;
top = bot + PAGE_SIZE*array_getnum(vmo->vmo_lpages);
/* Check guard band, if any */
assert(bot >= vmo->vmo_lower_redzone);
bot = bot - vmo->vmo_lower_redzone;
if (check_vaddr+sz > bot && check_vaddr < top) {
/* overlap */
return EINVAL;
}
}
/* Create a new vmo. All pages are marked zerofilled. */
vmo = vm_object_create(sz/PAGE_SIZE);
if (vmo == NULL) {
return ENOMEM;
}
vmo->vmo_base = vaddr;
vmo->vmo_lower_redzone = lower_redzone;
/* Add it to the parent address space. */
result = array_add(as->as_objects, vmo);
if (result) {
vm_object_destroy(as, vmo);
return result;
}
/* Done */
return 0;
}
