35,6 → 35,7 |
#include <arch/debugger.h> |
#include <arch/pm.h> |
#include <arch/asm.h> |
#include <adt/bitmap.h> |
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/** Perform ia32 specific tasks needed before the new task is run. |
* |
42,7 → 43,7 |
*/ |
void before_task_runs_arch(void) |
{ |
size_t iomap_size; |
count_t bits; |
ptr_16_32_t cpugdtr; |
descriptor_t *gdt_p; |
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52,18 → 53,24 |
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/* First, copy the I/O Permission Bitmap. */ |
spinlock_lock(&TASK->lock); |
iomap_size = TASK->arch.iomap_size; |
if (iomap_size) { |
ASSERT(TASK->arch.iomap); |
memcpy(CPU->arch.tss->iomap, TASK->arch.iomap, iomap_size); |
CPU->arch.tss->iomap[iomap_size] = 0xff; /* terminating byte */ |
if ((bits = TASK->arch.iomap.bits)) { |
bitmap_t iomap; |
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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 four bits because of the extra |
* convenience byte in TSS_IOMAP_SIZE. |
*/ |
bitmap_set_range(&iomap, TASK->arch.iomap.bits, 4); |
} |
spinlock_unlock(&TASK->lock); |
spinlock_unlock(&TASK->lock); |
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/* Second, adjust TSS segment limit. */ |
gdtr_store(&cpugdtr); |
gdt_p = (descriptor_t *) cpugdtr.base; |
gdt_setlimit(&gdt_p[TSS_DES], TSS_BASIC_SIZE + iomap_size - 1); |
gdt_setlimit(&gdt_p[TSS_DES], TSS_BASIC_SIZE + BITS2BYTES(bits) - 1); |
gdtr_load(&cpugdtr); |
} |
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