/*
This function will return:
0 - if failed
1 - if fmap was removed without IO
2 - if fmap removal begun and has IO (i.e async)
*/
int vmm_fmap_release_mreg(struct pm_task *task, struct vmm_memory_region *mreg)
{
struct vmm_fmap_descriptor *fmd = (struct vmm_fmap_descriptor*)mreg->descriptor;
if(fmd->status == VMM_FMAP_FLUSHING) // since we only allow one command on the task command
// queue, there cannot be a flush command executing..
// then. the task is dying.
{
// fmap is flushing.. we must wait until it completes
// but let's tell the current action we intend to close the FMAP
fmd->status = VMM_FMAP_CLOSING_RELEASE;
return 0;
}
else if(fmd->status != VMM_FMAP_ACTIVE)
{
return 0;
}
/* Begin removal only if references is 1 */
fmd->references--;
/* Unmap Pages from task address space */
UINT32 addr = (UINT32)mreg->tsk_node.low;
for(; addr < (UINT32)mreg->tsk_node.high; addr += 0x1000)
{
page_out(task->id, (ADDR)addr, 2);
}
/* Remove memory region from trees */
ma_remove(&task->vmm_info.regions, &mreg->tsk_node);
rb_remove(&task->vmm_info.regions_id, &mreg->tsk_id_node);
fmd->regions = fmd->regions->next;
if(fmd->regions)
fmd->regions->prev = NULL;
kfree(mreg);
if(fmd->references == 0)
{
/* Set FMAP as shutting down */
fmd->status = VMM_FMAP_CLOSING;
/* Write all dirty pages */
fmd->io_finished.params[0] = 0; // 0 will indicate we are closing and not flushing
fmd->io_finished.callback = vmm_fmap_flush_callback;
fmd->release_addr = (UINT32)mreg->tsk_node.low - 0x1000;
fmd->creating_task = task->id;
vmm_fmap_flush_callback(&fmd->iosrc, IO_RET_OK);
return 2;
}
return 1;
}
static int makemore(long s)
{
VMHEAD HUGE *h;
if (DMhandle == -1 || !VMlru.i) return(1);
while (s > 0L && VMlru.i) {
h = &VMbase[VMlru.p.b][VMlru.p.l];
page_out(h);
vm_unlink(h);
s -= h->size;
}
return(0);
}
UINT32 vmm_fmap(UINT16 task_id, UINT32 fileid, UINT16 fs_task, ADDR start, UINT32 size, UINT32 perms, UINT32 offset)
{
struct pm_task *task = tsk_get(task_id);
struct vmm_fmap_descriptor *new_fm = NULL;
struct vmm_memory_region *new_mreg = NULL, *mreg = NULL;
struct vmm_page_directory *pdir = NULL;
struct vmm_page_table *ptbl = NULL;
UINT32 dindex, tindex, tindex_max, pg_addr;
struct pm_thread *thr = NULL;
if(task == NULL) return PM_TASK_ID_INVALID;
/* On this implementation we will require start to be page aligned along with start + size */
if(((UINT32)start & 0x00000FFF) || (((UINT32)start + size) & 0x00000FFF))
return PM_INVALID_PARAMS;
/* Check address is not above max_addr */
if(task->vmm_info.max_addr <= (UINT32)start + size)
{
return PM_ERROR;
}
/* Translate address adding base. */
start = TRANSLATE_ADDR(start, ADDR);
// check lstart and lend are "safe" to map
if(loader_collides(task, start, start+size))
return FALSE;
/* Check region does not intersect with other region on this task address space. */
ma_node *n = ma_collition(&task->vmm_info.regions, (UINT32)start, (UINT32)start + size);
if(n)
{
return PM_MEM_COLITION;
}
/* Allocate structures */
new_fm = kmalloc(sizeof(struct vmm_fmap_descriptor)); // descriptor
if(new_fm == NULL) return PM_NOT_ENOUGH_MEM;
new_mreg = kmalloc(sizeof(struct vmm_memory_region)); // memory region on the task
if(new_mreg== NULL)
{
kfree(new_fm);
return PM_NOT_ENOUGH_MEM;
}
// get an ID for the memory descriptor on the task
if(!rb_free_value(&task->vmm_info.regions_id, &new_mreg->tsk_id_node.value))
{
kfree(new_fm);
kfree(new_mreg);
return PM_TOO_MANY_FILES_OPENED;
}
io_init_source(&new_fm->iosrc, FILE_IO_FMAP, new_mreg->tsk_id_node.value);
/* Initialize structures */
new_fm->io_finished.callback = NULL;
new_fm->iosrc.fs_service = fs_task;
new_fm->iosrc.smo = -1;
new_fm->status = VMM_FMAP_ACTIVE;
new_fm->offset = offset;
new_fm->creating_task = task->id;
new_fm->references = 1; // This should change when we can share files mapped between tasks.
new_fm->regions = new_mreg;
new_mreg->owner_task = task_id;
new_mreg->next = new_mreg->prev = NULL;
new_mreg->tsk_node.high = ((UINT32)start + size);
new_mreg->tsk_node.low = (UINT32)start;
new_mreg->flags = perms;
new_mreg->type = VMM_MEMREGION_FMAP;
new_mreg->descriptor = new_fm;
/*
Check pages are not swapped.
If pages are paged in, I'll page them out so an exception is raised if reading/writing.
*/
pdir = task->vmm_info.page_directory;
ptbl = NULL;
dindex = PM_LINEAR_TO_DIR(new_mreg->tsk_node.low);
for(; dindex < PM_LINEAR_TO_DIR(new_mreg->tsk_node.high); dindex++)
{
if(pdir->tables[dindex].ia32entry.present == 0 && pdir->tables[dindex].record.swapped == 1)
{
kfree(new_fm);
kfree(new_mreg);
return PM_NOT_ENOUGH_MEM;
}
if(pdir->tables[dindex].ia32entry.present == 1)
{
/* Table is present check pages */
if(dindex == PM_LINEAR_TO_DIR(new_mreg->tsk_node.low))
tindex = PM_LINEAR_TO_TAB(new_mreg->tsk_node.low);
else
tindex = 0;
if(dindex == PM_LINEAR_TO_DIR(new_mreg->tsk_node.high))
tindex_max = PM_LINEAR_TO_TAB(new_mreg->tsk_node.high);
else
tindex_max = 1024;
for(;tindex < tindex_max; tindex++)
{
if(ptbl->pages[tindex].entry.ia32entry.present == 0 && ptbl->pages[tindex].entry.record.swapped == 1)
{
kfree(new_fm);
kfree(new_mreg);
return PM_NOT_ENOUGH_MEM;
}
else if(ptbl->pages[tindex].entry.ia32entry.present == 1)
{
pg_addr = PHYSICAL2LINEAR(PG_ADDRESS(ptbl->pages[tindex].entry.phy_page_addr));
/* Page will be paged out */
page_out(task->id, (ADDR)(dindex * 0x400000 + (tindex << 12)), 2);
/* Put page onto PMAN */
vmm_put_page((ADDR)pg_addr);
task->vmm_info.page_count--;
}
}
}
}
/* Add new_mreg on the task lists */
ma_insert(&task->vmm_info.regions, &new_mreg->tsk_node);
rb_insert(&task->vmm_info.regions_id, &new_mreg->tsk_id_node, FALSE);
/* Once takeover is OK, new_fm will be added to the global list. */
/* Tell stdfss we are taking control of the file. */
new_fm->io_finished.params[0] = task->id;
new_fm->io_finished.callback = fmap_takeover_callback;
io_begin_takeover(&new_fm->iosrc, fileid, new_fm, task->id, 0xFFFFFFFF);
/* Block all threads for this task, until the file is opened so we don't have page faults */
task->state = TSK_MMAPPING;
thr = task->first_thread;
while(thr != NULL)
{
sch_deactivate(thr);
thr = thr->next_thread;
}
return PM_OK;
}
/* Tries to allocate and lock a frame for PAGE.
Returns the frame if successful, false on failure. */
static struct frame *
try_frame_alloc_and_lock (struct page *page)
{
size_t i;
lock_acquire (&scan_lock);
/* Find a free frame. */
for (i = 0; i < frame_cnt; i++)
{
struct frame *f = &frames[i];
if (!lock_try_acquire (&f->lock))
continue;
if (f->page == NULL)
{
f->page = page;
lock_release (&scan_lock);
return f;
}
lock_release (&f->lock);
}
/* No free frame. Find a frame to evict. */
for (i = 0; i < frame_cnt * 2; i++)
{
/* Get a frame. */
struct frame *f = &frames[hand];
if (++hand >= frame_cnt)
hand = 0;
if (!lock_try_acquire (&f->lock))
continue;
if (f->page == NULL)
{
f->page = page;
lock_release (&scan_lock);
return f;
}
if (page_accessed_recently (f->page))
{
lock_release (&f->lock);
continue;
}
lock_release (&scan_lock);
/* Evict this frame. */
if (!page_out (f->page))
{
lock_release (&f->lock);
return NULL;
}
f->page = page;
return f;
}
lock_release (&scan_lock);
return NULL;
}