void swap_init(void)
{
swap_disk = disk_get(1,1);
swap_bitmap = bitmap_create(disk_size(swap_disk)/SECTOR_PER_PAGE);
bitmap_set_all(swap_bitmap, 0);
}
// all the used swap slots are set to TRUE
void
swap_read_and_free (disk_sector_t idx, void *upage)
{
lock_acquire (&swap_table_lock);
// all the swap sectors must be in use
// bitmap_all returns true if all pages are in use (i.e. TRUE)
// take care of the edge cases
ASSERT (idx != SECTOR_ERROR);
ASSERT (bitmap_all (swap_table, idx, SLOT_SIZE));
struct disk *swap = disk_get (1,1);
if (!swap)
PANIC ("No swap disk found\n");
// read in the upage buffer
int offset;
for (offset = 0; offset < SLOT_SIZE; offset++) {
// printf ("Swap read sector %d at address %p\n",idx+offset, upage +(offset * DISK_SECTOR_SIZE));
disk_read (swap, idx + offset, upage + (offset * DISK_SECTOR_SIZE));
}
// vacant the swap slot
bitmap_set_multiple (swap_table, idx, SLOT_SIZE, false);
lock_release (&swap_table_lock);
// printf ("Swap read called at %d for %p\n",idx,upage);
}
// returns the start sector of the swap slot where upage is written
// all the vacant swap slots are set to FALSE
size_t
swap_write (void *kpage)
{
// ASSERT (kpage);
// printf ("Swap write called for %p\n",upage);
lock_acquire (&swap_table_lock);
size_t idx = bitmap_scan_and_flip (swap_table, 0, SLOT_SIZE, false);
if (idx == BITMAP_ERROR) {
PANIC ("No more swap slot avaiable\n");
}
struct disk *swap = disk_get (1,1);
if (!swap)
PANIC ("No swap disk found\n");
int offset;
for (offset = 0; offset < SLOT_SIZE; offset++) {
//disk_write (swap, idx + offset, upage + (offset * DISK_SECTOR_SIZE));
disk_write (swap, idx + offset, kpage + (offset * DISK_SECTOR_SIZE));
}
lock_release (&swap_table_lock);
return idx;
}
void
swap_init (void)
{
swap_disk = disk_get (1, 1);
swap_slot = bitmap_create ((size_t)disk_size (swap_disk));
lock_init (&swap_lock);
lock_init (&swap_bitmap_lock);
}
/* Swap Table access methods. */
void swap_init ()
{
struct disk *swap = disk_get (1,1); // swap 1:1 channel:device no
if (!swap)
PANIC ("No swap disk found\n");
disk_sector_t size = disk_size (swap);
swap_table = bitmap_create (size);
if (!swap_table)
PANIC ("Cannot create bitmap for the swap table\n");
lock_init (&swap_table_lock);
}
/* Initializes the file system module.
If FORMAT is true, reformats the file system. */
void
filesys_init (bool format)
{
filesys_disk = disk_get (0, 1);
if (filesys_disk == NULL)
PANIC ("hd0:1 (hdb) not present, file system initialization failed");
inode_init ();
free_map_init ();
if (format)
do_format ();
free_map_open ();
}
