/**
* exaOffscreenFree frees an allocation.
*
* @param pScreen current screen
* @param area offscreen area to free
*
* exaOffscreenFree frees an allocation created by exaOffscreenAlloc. Note that
* the save callback of the area is not called, and it is up to the driver to
* do any cleanup necessary as a result.
*
* @return pointer to the newly freed area. This behavior should not be relied
* on.
*/
ExaOffscreenArea *
exaOffscreenFree (ScreenPtr pScreen, ExaOffscreenArea *area)
{
ExaScreenPriv(pScreen);
ExaOffscreenArea *next = area->next;
ExaOffscreenArea *prev;
DBG_OFFSCREEN (("Free 0x%x -> 0x%x (0x%x)\n", area->size,
area->base_offset, area->offset));
ExaOffscreenValidate (pScreen);
area->state = ExaOffscreenAvail;
area->save = NULL;
area->score = 0;
/*
* Find previous area
*/
if (area == pExaScr->info->offScreenAreas)
prev = NULL;
else
for (prev = pExaScr->info->offScreenAreas; prev; prev = prev->next)
if (prev->next == area)
break;
/* link with next area if free */
if (next && next->state == ExaOffscreenAvail)
ExaOffscreenMerge (area);
/* link with prev area if free */
if (prev && prev->state == ExaOffscreenAvail)
{
area = prev;
ExaOffscreenMerge (area);
}
ExaOffscreenValidate (pScreen);
DBG_OFFSCREEN(("\tdone freeing\n"));
return area;
}
KdOffscreenArea *
KdOffscreenFree (ScreenPtr pScreen, KdOffscreenArea *area)
{
KdScreenPriv(pScreen);
KdOffscreenArea *next = area->next;
KdOffscreenArea *prev;
DBG_OFFSCREEN (("Free 0x%x -> 0x%x\n", area->size, area->offset));
KdOffscreenValidate (pScreen);
area->state = KdOffscreenAvail;
area->save = 0;
area->offset = area->save_offset;
area->score = 0;
/*
* Find previous area
*/
if (area == pScreenPriv->off_screen_areas)
prev = 0;
else
for (prev = pScreenPriv->off_screen_areas; prev; prev = prev->next)
if (prev->next == area)
break;
/* link with next area if free */
if (next && next->state == KdOffscreenAvail)
KdOffscreenMerge (area);
/* link with prev area if free */
if (prev && prev->state == KdOffscreenAvail)
{
area = prev;
KdOffscreenMerge (area);
}
KdOffscreenValidate (pScreen);
return area;
}
KdOffscreenArea *
KdOffscreenAlloc (ScreenPtr pScreen, int size, int align,
Bool locked,
KdOffscreenSaveProc save,
pointer privData)
{
KdOffscreenArea *area, *begin, *best;
KdScreenPriv (pScreen);
int tmp, real_size = 0, best_score;
KdOffscreenValidate (pScreen);
if (!align)
align = 1;
if (!size)
{
DBG_OFFSCREEN (("Alloc 0x%x -> EMPTY\n", size));
return NULL;
}
/* throw out requests that cannot fit */
if (size > (pScreenPriv->screen->memory_size - pScreenPriv->screen->off_screen_base))
{
DBG_OFFSCREEN (("Alloc 0x%x -> TOBIG\n", size));
return NULL;
}
/* Try to find a free space that'll fit. */
for (area = pScreenPriv->off_screen_areas; area; area = area->next)
{
/* skip allocated areas */
if (area->state != KdOffscreenAvail)
continue;
/* adjust size to match alignment requirement */
real_size = size;
tmp = area->offset % align;
if (tmp)
real_size += (align - tmp);
/* does it fit? */
if (real_size <= area->size)
break;
}
if (!area)
{
/*
* Kick out existing users to make space.
*
* First, locate a region which can hold the desired object.
*/
/* prev points at the first object to boot */
best = NULL;
best_score = MAXINT;
for (begin = pScreenPriv->off_screen_areas; begin != NULL;
begin = begin->next)
{
int avail, score;
KdOffscreenArea *scan;
if (begin->state == KdOffscreenLocked)
continue;
/* adjust size to match alignment requirement */
real_size = size;
tmp = begin->offset % align;
if (tmp)
real_size += (align - tmp);
avail = 0;
score = 0;
/* now see if we can make room here, and how "costly" it'll be. */
for (scan = begin; scan != NULL; scan = scan->next)
{
if (scan->state == KdOffscreenLocked) {
/* Can't make room here, start after this locked area. */
begin = scan->next;
break;
}
/* Score should only be non-zero for KdOffscreenRemovable */
score += scan->score;
avail += scan->size;
if (avail >= real_size)
break;
}
/* Is it the best option we've found so far? */
if (avail >= real_size && score < best_score) {
best = begin;
best_score = score;
}
}
area = best;
if (!area)
{
DBG_OFFSCREEN (("Alloc 0x%x -> NOSPACE\n", size));
/* Could not allocate memory */
KdOffscreenValidate (pScreen);
return NULL;
}
/* adjust size to match alignment requirement */
real_size = size;
tmp = begin->offset % align;
if (tmp)
real_size += (align - tmp);
/*
* Kick out first area if in use
*/
if (area->state != KdOffscreenAvail)
area = KdOffscreenKickOut (pScreen, area);
/*
* Now get the system to merge the other needed areas together
*/
while (area->size < real_size)
{
assert (area->next && area->next->state == KdOffscreenRemovable);
(void) KdOffscreenKickOut (pScreen, area->next);
}
}
/* save extra space in new area */
if (real_size < area->size)
{
KdOffscreenArea *new_area = xalloc (sizeof (KdOffscreenArea));
if (!new_area)
return NULL;
new_area->offset = area->offset + real_size;
new_area->size = area->size - real_size;
new_area->state = KdOffscreenAvail;
new_area->save = 0;
new_area->score = 0;
new_area->next = area->next;
area->next = new_area;
area->size = real_size;
}
/*
* Mark this area as in use
*/
if (locked)
area->state = KdOffscreenLocked;
else
area->state = KdOffscreenRemovable;
area->privData = privData;
area->save = save;
area->score = 0;
area->save_offset = area->offset;
{
int tmp = area->offset % align;
if (tmp)
area->offset += (align - tmp);
}
KdOffscreenValidate (pScreen);
DBG_OFFSCREEN (("Alloc 0x%x -> 0x%x\n", size, area->offset));
return area;
}
