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#include "mm/mobj.h"
#include "mm/page.h"
#include "mm/pframe.h"
#include "mm/slab.h"
#include "util/debug.h"
#include "util/string.h"
/* for debugging/verification purposes */
int anon_count = 0;
static slab_allocator_t *anon_allocator;
static long anon_fill_pframe(mobj_t *o, pframe_t *pf);
static long anon_flush_pframe(mobj_t *o, pframe_t *pf);
static void anon_destructor(mobj_t *o);
static mobj_ops_t anon_mobj_ops = {.get_pframe = NULL,
.fill_pframe = anon_fill_pframe,
.flush_pframe = anon_flush_pframe,
.destructor = anon_destructor};
/*
* Initialize anon_allocator using the slab allocator.
*/
void anon_init()
{
anon_allocator = slab_allocator_create("anon", sizeof(mobj_t));
}
/*
* The mobj should be locked upon successful return. Use mobj_init and
* mobj_lock.
*/
mobj_t *anon_create()
{
// make a new mobj
mobj_t *mobj = (mobj_t *)slab_obj_alloc(anon_allocator);
// initialize the mobj
if (mobj)
{
mobj_init(mobj, MOBJ_ANON, &anon_mobj_ops);
mobj_lock(mobj);
return mobj;
}
panic("MINE anon_create: slab_obj_alloc failed");
}
/*
* This function is not complicated -- think about what the pframe should look
* like for an anonymous object
*/
static long anon_fill_pframe(mobj_t *o, pframe_t *pf)
{
memset(pf->pf_addr, 0, PAGE_SIZE);
return 0;
}
static long anon_flush_pframe(mobj_t *o, pframe_t *pf) { return 0; }
/*
* Release all resources associated with an anonymous object.
*
* Hints:
* 1) Call mobj_default_destructor() to free pframes
* 2) Free the mobj
*/
static void anon_destructor(mobj_t *o)
{
// call the default destructor
mobj_default_destructor(o);
// free the mobj
slab_obj_free(anon_allocator, o);
}
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