mirror of https://gitee.com/openkylin/linux.git
107 lines
2.8 KiB
C
107 lines
2.8 KiB
C
/*
|
|
* Copyright (C) 2006 Hollis Blanchard <hollisb@us.ibm.com>, IBM Corporation
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*/
|
|
|
|
#include <linux/mm.h>
|
|
#include <linux/err.h>
|
|
|
|
static unsigned long kernel_virtual_offset;
|
|
static int is_xencomm_initialized;
|
|
|
|
/* for xen early printk. It uses console io hypercall which uses xencomm.
|
|
* However early printk may use it before xencomm initialization.
|
|
*/
|
|
int
|
|
xencomm_is_initialized(void)
|
|
{
|
|
return is_xencomm_initialized;
|
|
}
|
|
|
|
void
|
|
xencomm_initialize(void)
|
|
{
|
|
kernel_virtual_offset = KERNEL_START - ia64_tpa(KERNEL_START);
|
|
is_xencomm_initialized = 1;
|
|
}
|
|
|
|
/* Translate virtual address to physical address. */
|
|
unsigned long
|
|
xencomm_vtop(unsigned long vaddr)
|
|
{
|
|
struct page *page;
|
|
struct vm_area_struct *vma;
|
|
|
|
if (vaddr == 0)
|
|
return 0UL;
|
|
|
|
if (REGION_NUMBER(vaddr) == 5) {
|
|
pgd_t *pgd;
|
|
pud_t *pud;
|
|
pmd_t *pmd;
|
|
pte_t *ptep;
|
|
|
|
/* On ia64, TASK_SIZE refers to current. It is not initialized
|
|
during boot.
|
|
Furthermore the kernel is relocatable and __pa() doesn't
|
|
work on addresses. */
|
|
if (vaddr >= KERNEL_START
|
|
&& vaddr < (KERNEL_START + KERNEL_TR_PAGE_SIZE))
|
|
return vaddr - kernel_virtual_offset;
|
|
|
|
/* In kernel area -- virtually mapped. */
|
|
pgd = pgd_offset_k(vaddr);
|
|
if (pgd_none(*pgd) || pgd_bad(*pgd))
|
|
return ~0UL;
|
|
|
|
pud = pud_offset(pgd, vaddr);
|
|
if (pud_none(*pud) || pud_bad(*pud))
|
|
return ~0UL;
|
|
|
|
pmd = pmd_offset(pud, vaddr);
|
|
if (pmd_none(*pmd) || pmd_bad(*pmd))
|
|
return ~0UL;
|
|
|
|
ptep = pte_offset_kernel(pmd, vaddr);
|
|
if (!ptep)
|
|
return ~0UL;
|
|
|
|
return (pte_val(*ptep) & _PFN_MASK) | (vaddr & ~PAGE_MASK);
|
|
}
|
|
|
|
if (vaddr > TASK_SIZE) {
|
|
/* percpu variables */
|
|
if (REGION_NUMBER(vaddr) == 7 &&
|
|
REGION_OFFSET(vaddr) >= (1ULL << IA64_MAX_PHYS_BITS))
|
|
ia64_tpa(vaddr);
|
|
|
|
/* kernel address */
|
|
return __pa(vaddr);
|
|
}
|
|
|
|
/* XXX double-check (lack of) locking */
|
|
vma = find_extend_vma(current->mm, vaddr);
|
|
if (!vma)
|
|
return ~0UL;
|
|
|
|
/* We assume the page is modified. */
|
|
page = follow_page(vma, vaddr, FOLL_WRITE | FOLL_TOUCH);
|
|
if (IS_ERR_OR_NULL(page))
|
|
return ~0UL;
|
|
|
|
return (page_to_pfn(page) << PAGE_SHIFT) | (vaddr & ~PAGE_MASK);
|
|
}
|