/**
* Test bit in bitmap
*
* @v bitmap Bitmap
* @v bit Bit index
* @ret is_set Bit is set
*/
int bitmap_test ( struct bitmap *bitmap, unsigned int bit ) {
unsigned int index = BITMAP_INDEX ( bit );
bitmap_block_t mask = BITMAP_MASK ( bit );
if ( bit >= bitmap->length )
return 0;
return ( bitmap->blocks[index] & mask );
}
/*
* Sets a given bit in the bitmap. If the bit is already set
* it returns -1, 0 otherwise.
*/
int
bitmap_set(bitmap_t bitmap, uint32_t bit)
{
if(bitmap_is_set(bitmap, bit))
return -1;
bitmap[bit/BITMAP_BITS_PER_ENTRY] |=
BITMAP_MASK(BITMAP_REMAINING_BITS(bit));
return 0;
}
/**
* Set bit in bitmap
*
* @v bitmap Bitmap
* @v bit Bit index
*/
void bitmap_set ( struct bitmap *bitmap, unsigned int bit ) {
unsigned int index = BITMAP_INDEX ( bit );
bitmap_block_t mask = BITMAP_MASK ( bit );
DBGC ( bitmap, "Bitmap %p setting bit %d\n", bitmap, bit );
/* Update bitmap */
bitmap->blocks[index] |= mask;
/* Update first gap counter */
while ( bitmap_test ( bitmap, bitmap->first_gap ) ) {
bitmap->first_gap++;
}
}
static inline int
bb_table_lookup(bb_table_t *table, uint addr)
{
byte *bm = table->bm;
PRINT(5, "lookup "PFX" in bb table "PFX"\n",
(ptr_uint_t)addr, (ptr_uint_t)table);
/* We see this and it seems to be erroneous data from the pdb,
* xref drsym_enumerate_lines() from drsyms.
*/
if (table->size <= addr)
return BB_TABLE_ENTRY_INVALID;
if (bm[BITMAP_INDEX(addr)] == 0xff ||
TEST(BITMAP_MASK(BITMAP_OFFSET(addr)), bm[BITMAP_INDEX(addr)]))
return BB_TABLE_ENTRY_SET;
return BB_TABLE_ENTRY_CLEAR;
}
static inline bool
bb_table_add(bb_table_t *table, bb_entry_t *entry)
{
byte *bm;
uint idx, offs, addr_end, idx_end, offs_end, i;
if (table == BB_TABLE_IGNORE)
return false;
if (table->size <= entry->start + entry->size) {
WARN(3, "Wrong range "PFX"-"PFX" or table size "PFX" for table "PFX"\n",
(ptr_uint_t)entry->start,
(ptr_uint_t)entry->start + entry->size,
(ptr_uint_t)table->size,
(ptr_uint_t)table);
return false;
}
bm = table->bm;
idx = BITMAP_INDEX(entry->start);
/* we assume that the whole bb is seen if its start addr is seen */
if (bm[idx] == BB_TABLE_RANGE_SET)
return false;
offs = BITMAP_OFFSET(entry->start);
if (TEST(BITMAP_MASK(offs), bm[idx]))
return false;
/* now we add a new bb */
PRINT(6, "Add "PFX"-"PFX" in table "PFX"\n",
(ptr_uint_t)entry->start,
(ptr_uint_t)entry->start + entry->size,
(ptr_uint_t)table);
addr_end = entry->start + entry->size - 1;
idx_end = BITMAP_INDEX(addr_end);
offs_end = (idx_end > idx) ? BITS_PER_BYTE-1 : BITMAP_OFFSET(addr_end);
/* first byte in the bitmap */
bm[idx] |= bitmap_set[offs][offs_end];
/* set all the middle byte */
for (i = idx + 1; i < idx_end; i++)
bm[i] = BB_TABLE_RANGE_SET;
/* last byte in the bitmap */
if (idx_end > idx) {
offs_end = BITMAP_OFFSET(addr_end);
bm[idx_end] |= bitmap_set[0][offs_end];
}
return true;
}
void free_pages(struct buddy *pool, struct page *page)
{
struct page *buddy;
struct buddy_freelist *freelist;
unsigned int order, index;
order = GET_PAGE_ORDER(page);
freelist = &pool->free[order];
index = PAGE_INDEX(page->addr);
pool->nr_free += 1U << order;
while (order < BUDDY_MAX_ORDER) {
BITMAP_TOGGLE(freelist->bitmap, index, order);
/* If it was 0 before toggling, it means both of buddies
* were allocated. So nothing can be merged to upper order
* as one of them is still allocated. Otherwise, both of
* them are free now. Therefore merge it to upper order. */
if (BITMAP_MASK(freelist->bitmap, index, order))
break;
/* find buddy and detach it from current order to merge */
buddy = &mem_map[index ^ (1U << order)];
list_del(&buddy->link);
/* grab the first address of merging buddies */
index &= ~(1U << order);
order++;
freelist++;
}
list_add(&mem_map[index].link, &freelist->list);
RESET_PAGE_FLAG(page, PAGE_BUDDY);
}
/*
* Returns if the bit is set or not
*/
int
bitmap_is_set(bitmap_t bitmap, uint32_t bit)
{
return bitmap[bit / BITMAP_BITS_PER_ENTRY] &
BITMAP_MASK(BITMAP_REMAINING_BITS(bit));
}