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Ignore whitespace Rev 1255 → Rev 1256

/kernel/trunk/arch/ia32/src/proc/scheduler.c
35,8 → 35,7
#include <arch/debugger.h>
#include <arch/pm.h>
#include <arch/asm.h>
#include <adt/bitmap.h>
#include <print.h>
#include <arch/ddi/ddi.h>
 
/** Perform ia32 specific tasks needed before the new task is run.
*
44,42 → 43,7
*/
void before_task_runs_arch(void)
{
count_t bits;
ptr_16_32_t cpugdtr;
descriptor_t *gdt_p;
 
/*
* Switch the I/O Permission Bitmap, if necessary.
*/
 
/* First, copy the I/O Permission Bitmap. */
spinlock_lock(&TASK->lock);
if ((bits = TASK->arch.iomap.bits)) {
bitmap_t iomap;
ASSERT(TASK->arch.iomap.map);
bitmap_initialize(&iomap, CPU->arch.tss->iomap, TSS_IOMAP_SIZE * 8);
bitmap_copy(&iomap, &TASK->arch.iomap, TASK->arch.iomap.bits);
/*
* It is safe to set the trailing eight bits because of the extra
* convenience byte in TSS_IOMAP_SIZE.
*/
bitmap_set_range(&iomap, TASK->arch.iomap.bits, 8);
}
spinlock_unlock(&TASK->lock);
 
/* Second, adjust TSS segment limit. */
gdtr_store(&cpugdtr);
gdt_p = (descriptor_t *) cpugdtr.base;
gdt_setlimit(&gdt_p[TSS_DES], TSS_BASIC_SIZE + BITS2BYTES(bits) - 1);
gdtr_load(&cpugdtr);
 
/*
* Before we load new TSS limit, the current TSS descriptor
* type must be changed to describe inactive TSS.
*/
gdt_p[TSS_DES].access = AR_PRESENT | AR_TSS | DPL_KERNEL;
tr_load(selector(TSS_DES));
io_perm_bitmap_install();
}
 
/** Perform ia32 specific tasks needed before the new thread is scheduled.