/* i915_mem.c -- Simple agp/fb memory manager for i915 -*- linux-c -*-
*/
/**************************************************************************
*
* Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
* All Rights Reserved.
*
**************************************************************************/
#include "i915.h"
#include "drmP.h"
#include "drm.h"
#include "i915_drm.h"
#include "i915_drv.h"
/* This memory manager is integrated into the global/local lru
* mechanisms used by the clients. Specifically, it operates by
* setting the 'in_use' fields of the global LRU to indicate whether
* this region is privately allocated to a client.
*
* This does require the client to actually respect that field.
*
* Currently no effort is made to allocate 'private' memory in any
* clever way - the LRU information isn't used to determine which
* block to allocate, and the ring is drained prior to allocations --
* in other words allocation is expensive.
*/
static void mark_block(drm_device_t * dev, struct mem_block *p, int in_use)
{
drm_i915_private_t *dev_priv = dev->dev_private;
drm_i915_sarea_t *sarea_priv = dev_priv->sarea_priv;
drm_tex_region_t *list;
unsigned shift, nr;
unsigned start;
unsigned end;
unsigned i;
int age;
shift = dev_priv->tex_lru_log_granularity;
nr = I915_NR_TEX_REGIONS;
start = p->start >> shift;
end = (p->start + p->size - 1) >> shift;
age = ++sarea_priv->texAge;
list = sarea_priv->texList;
/* Mark the regions with the new flag and update their age. Move
* them to head of list to preserve LRU semantics.
*/
for (i = start; i <= end; i++) {
list[i].in_use = in_use;
list[i].age = age;
/* remove_from_list(i)
*/
list[(unsigned)list[i].next].prev = list[i].prev;
list[(unsigned)list[i].prev].next = list[i].next;
/* insert_at_head(list, i)
*/
list[i].prev = nr;
list[i].next = list[nr].next;
list[(unsigned)list[nr].next].prev = i;
list[nr].next = i;
}
}
/* Very simple allocator for agp memory, working on a static range
* already mapped into each client's address space.
*/
static struct mem_block *split_block(struct mem_block *p, int start, int size,
DRMFILE filp)
{
/* Maybe cut off the start of an existing block */
if (start > p->start) {
struct mem_block *newblock = DRM(alloc)(sizeof(*newblock), DRM_MEM_BUFLISTS);
if (!newblock)
goto out;
newblock->start = start;
newblock->size = p->size - (start - p->start);
newblock->filp = NULL;
newblock->next = p->next;
newblock->prev = p;
p->next->prev = newblock;
p->next = newblock;
p->size -= newblock->size;
p = newblock;
}
/* Maybe cut off the end of an existing block */
if (size < p->size) {
struct mem_block *newblock = DRM(alloc)(sizeof(*newblock), DRM_MEM_BUFLISTS);
if (!newblock)
goto out;
newblock->start = start + size;
newblock->size = p->size - size;
newblock->filp = NULL;
newblock->next = p->next;
newblock->prev = p;
p->next->prev = newblock;
p->next = newblock;
p->size = size;
}
out:
/* Our block is in the middle */
p->filp = filp;
return p;
}
static struct mem_block *alloc_block(struct mem_block *heap, int size,
int align2, DRMFILE filp)
{
struct mem_block *p;
int mask = (1 << align2) - 1;
for (p = heap->next; p != heap; p = p->next) {
int start = (p->start + mask) & ~mask;
if (p->filp == NULL && start + size <= p->start + p->size)
return split_block(p, start, size, filp);
}
return NULL;
}
static struct mem_block *find_block(struct mem_block *heap, int start)
{
struct mem_block *p;
for (
all: app
#CFLAGS = -g -ansi -pedantic -DPOSIX_C_SOURCE=199309L \
# -D_POSIX_SOURCE -D_XOPEN_SOURCE -D_BSD_SOURCE -D_SVID_SOURCE \
app: demo.c
@gcc $(CFLAGS) -o app -Wall -I../../libdrm -I../../shared-core -L../../libdrm/.libs -ldrm demo.c
clean:
@rm -f app
run: app
sudo ./test