C++ (Cpp) i386_trunc_page Examples

Example #1

File: db_memrw.c Project: NKSG/INTER_MANET_NS3

/*
 * Write bytes to kernel address space for debugger.
 */
void
db_write_bytes(vaddr_t addr, size_t size, char *data)
{
	char	*dst;

	pt_entry_t *ptep0 = 0;
	pt_entry_t	oldmap0 = { 0 };
	vaddr_t	addr1;
	pt_entry_t *ptep1 = 0;
	pt_entry_t	oldmap1 = { 0 };
	extern char	etext;

	if (addr >= VM_MIN_KERNEL_ADDRESS &&
	    addr < (vaddr_t)&etext) {
		ptep0 = PTE_BASE + i386_btop(addr);
		oldmap0 = *ptep0;
		*(int *)ptep0 |= /* INTEL_PTE_WRITE */ PG_RW;

		addr1 = i386_trunc_page(addr + size - 1);
		if (i386_trunc_page(addr) != addr1) {
			/* data crosses a page boundary */
			ptep1 = PTE_BASE + i386_btop(addr1);
			oldmap1 = *ptep1;
			*(int *)ptep1 |= /* INTEL_PTE_WRITE */ PG_RW;
		}
		tlbflush();
	}

	dst = (char *)addr;

	while (size-- > 0)
		*dst++ = *data++;

	if (ptep0) {
		*ptep0 = oldmap0;
		if (ptep1)
			*ptep1 = oldmap1;
		tlbflush();
	}
}

Example #2

File: db_interface.c Project: LastAvenger/gnumach

/*
 * Write bytes to kernel address space for debugger.
 */
void
db_write_bytes(
	vm_offset_t	addr,
	int		size,
	char		*data,
	task_t		task)
{
	char		*dst;

	pt_entry_t *ptep0 = 0;
	pt_entry_t	oldmap0 = 0;
	vm_offset_t	addr1;
	pt_entry_t *ptep1 = 0;
	pt_entry_t	oldmap1 = 0;
	extern char	etext;

	if ((addr < VM_MIN_KERNEL_ADDRESS) ^
	    ((addr + size) <= VM_MIN_KERNEL_ADDRESS)) {
	    db_error("\ncannot write data into mixed space\n");
	    /* NOTREACHED */
	}
	if (addr < VM_MIN_KERNEL_ADDRESS) {
	    if (task) {
		db_write_bytes_user_space(addr, size, data, task);
		return;
	    } else if (db_current_task() == TASK_NULL) {
		db_printf("\nbad address %x\n", addr);
		db_error(0);
		/* NOTREACHED */
	    }
	}

	if (addr >= VM_MIN_KERNEL_ADDRESS &&
	    addr <= (vm_offset_t)&etext)
	{
	    ptep0 = pmap_pte(kernel_pmap, addr);
	    oldmap0 = *ptep0;
	    *ptep0 |= INTEL_PTE_WRITE;

	    addr1 = i386_trunc_page(addr + size - 1);
	    if (i386_trunc_page(addr) != addr1) {
		/* data crosses a page boundary */

		ptep1 = pmap_pte(kernel_pmap, addr1);
		oldmap1 = *ptep1;
		*ptep1 |= INTEL_PTE_WRITE;
	    }
	    if (CPU_HAS_FEATURE(CPU_FEATURE_PGE))
		set_cr4(get_cr4() & ~CR4_PGE);
	    flush_tlb();
	}

	dst = (char *)addr;

	while (--size >= 0)
	    *dst++ = *data++;

	if (ptep0) {
	    *ptep0 = oldmap0;
	    if (ptep1) {
		*ptep1 = oldmap1;
	    }
	    flush_tlb();
	    if (CPU_HAS_FEATURE(CPU_FEATURE_PGE))
		set_cr4(get_cr4() | CR4_PGE);
	}
}