158 строки
3.6 KiB
C
158 строки
3.6 KiB
C
// SPDX-License-Identifier: GPL-2.0 OR MIT
|
|
/******************************************************************************
|
|
* grant_table.c
|
|
* x86 specific part
|
|
*
|
|
* Granting foreign access to our memory reservation.
|
|
*
|
|
* Copyright (c) 2005-2006, Christopher Clark
|
|
* Copyright (c) 2004-2005, K A Fraser
|
|
* Copyright (c) 2008 Isaku Yamahata <yamahata at valinux co jp>
|
|
* VA Linux Systems Japan. Split out x86 specific part.
|
|
*/
|
|
|
|
#include <linux/sched.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/vmalloc.h>
|
|
|
|
#include <xen/interface/xen.h>
|
|
#include <xen/page.h>
|
|
#include <xen/grant_table.h>
|
|
#include <xen/xen.h>
|
|
|
|
#include <asm/pgtable.h>
|
|
|
|
static struct gnttab_vm_area {
|
|
struct vm_struct *area;
|
|
pte_t **ptes;
|
|
} gnttab_shared_vm_area, gnttab_status_vm_area;
|
|
|
|
int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
|
|
unsigned long max_nr_gframes,
|
|
void **__shared)
|
|
{
|
|
void *shared = *__shared;
|
|
unsigned long addr;
|
|
unsigned long i;
|
|
|
|
if (shared == NULL)
|
|
*__shared = shared = gnttab_shared_vm_area.area->addr;
|
|
|
|
addr = (unsigned long)shared;
|
|
|
|
for (i = 0; i < nr_gframes; i++) {
|
|
set_pte_at(&init_mm, addr, gnttab_shared_vm_area.ptes[i],
|
|
mfn_pte(frames[i], PAGE_KERNEL));
|
|
addr += PAGE_SIZE;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
|
|
unsigned long max_nr_gframes,
|
|
grant_status_t **__shared)
|
|
{
|
|
grant_status_t *shared = *__shared;
|
|
unsigned long addr;
|
|
unsigned long i;
|
|
|
|
if (shared == NULL)
|
|
*__shared = shared = gnttab_status_vm_area.area->addr;
|
|
|
|
addr = (unsigned long)shared;
|
|
|
|
for (i = 0; i < nr_gframes; i++) {
|
|
set_pte_at(&init_mm, addr, gnttab_status_vm_area.ptes[i],
|
|
mfn_pte(frames[i], PAGE_KERNEL));
|
|
addr += PAGE_SIZE;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void arch_gnttab_unmap(void *shared, unsigned long nr_gframes)
|
|
{
|
|
pte_t **ptes;
|
|
unsigned long addr;
|
|
unsigned long i;
|
|
|
|
if (shared == gnttab_status_vm_area.area->addr)
|
|
ptes = gnttab_status_vm_area.ptes;
|
|
else
|
|
ptes = gnttab_shared_vm_area.ptes;
|
|
|
|
addr = (unsigned long)shared;
|
|
|
|
for (i = 0; i < nr_gframes; i++) {
|
|
set_pte_at(&init_mm, addr, ptes[i], __pte(0));
|
|
addr += PAGE_SIZE;
|
|
}
|
|
}
|
|
|
|
static int arch_gnttab_valloc(struct gnttab_vm_area *area, unsigned nr_frames)
|
|
{
|
|
area->ptes = kmalloc_array(nr_frames, sizeof(*area->ptes), GFP_KERNEL);
|
|
if (area->ptes == NULL)
|
|
return -ENOMEM;
|
|
|
|
area->area = alloc_vm_area(PAGE_SIZE * nr_frames, area->ptes);
|
|
if (area->area == NULL) {
|
|
kfree(area->ptes);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void arch_gnttab_vfree(struct gnttab_vm_area *area)
|
|
{
|
|
free_vm_area(area->area);
|
|
kfree(area->ptes);
|
|
}
|
|
|
|
int arch_gnttab_init(unsigned long nr_shared, unsigned long nr_status)
|
|
{
|
|
int ret;
|
|
|
|
if (!xen_pv_domain())
|
|
return 0;
|
|
|
|
ret = arch_gnttab_valloc(&gnttab_shared_vm_area, nr_shared);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
/*
|
|
* Always allocate the space for the status frames in case
|
|
* we're migrated to a host with V2 support.
|
|
*/
|
|
ret = arch_gnttab_valloc(&gnttab_status_vm_area, nr_status);
|
|
if (ret < 0)
|
|
goto err;
|
|
|
|
return 0;
|
|
err:
|
|
arch_gnttab_vfree(&gnttab_shared_vm_area);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
#ifdef CONFIG_XEN_PVH
|
|
#include <xen/events.h>
|
|
#include <xen/xen-ops.h>
|
|
static int __init xen_pvh_gnttab_setup(void)
|
|
{
|
|
if (!xen_pvh_domain())
|
|
return -ENODEV;
|
|
|
|
xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames();
|
|
|
|
return xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn,
|
|
&xen_auto_xlat_grant_frames.vaddr,
|
|
xen_auto_xlat_grant_frames.count);
|
|
}
|
|
/* Call it _before_ __gnttab_init as we need to initialize the
|
|
* xen_auto_xlat_grant_frames first. */
|
|
core_initcall(xen_pvh_gnttab_setup);
|
|
#endif
|