Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

xen: use _PAGE_IOMAP in ioremap to do machine mappings

Browse source 
In a Xen domain, ioremap operates on machine addresses, not
pseudo-physical addresses.  We use _PAGE_IOMAP to determine whether a
mapping is intended for machine addresses.

[ Impact: allow Xen domain to map real hardware ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Jeremy Fitzhardinge 2010-02-04 14:46:34 -08:00 committed by Konrad Rzeszutek Wilk
parent e40152ee1e
commit c0011dbfce
2 changed files with 71 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
arch/x86/include/asm/xen/page.h
View file

@ -112,13 +112,9 @@ static inline xpaddr_t machine_to_phys(xmaddr_t machine)
*/
static inline unsigned long mfn_to_local_pfn(unsigned long mfn)
{
extern unsigned long max_mapnr;
unsigned long pfn = mfn_to_pfn(mfn);
if ((pfn < max_mapnr)
&& !xen_feature(XENFEAT_auto_translated_physmap)
&& (get_phys_to_machine(pfn) != mfn))
return max_mapnr; /* force !pfn_valid() */
/* XXX fixme; not true with sparsemem */
if (get_phys_to_machine(pfn) != mfn)
return -1; /* force !pfn_valid() */
return pfn;
}

71
arch/x86/xen/mmu.c
View file

@ -56,9 +56,11 @@
#include <asm/xen/hypercall.h>
#include <asm/xen/hypervisor.h>
#include <xen/xen.h>
#include <xen/page.h>
#include <xen/interface/xen.h>
#include <xen/interface/version.h>
#include <xen/interface/memory.h>
#include <xen/hvc-console.h>
#include "multicalls.h"
@ -377,6 +379,28 @@ static bool xen_page_pinned(void *ptr)
return PagePinned(page);
}
static bool xen_iomap_pte(pte_t pte)
{
return xen_initial_domain() && (pte_flags(pte) & _PAGE_IOMAP);
}
static void xen_set_iomap_pte(pte_t *ptep, pte_t pteval)
{
struct multicall_space mcs;
struct mmu_update *u;
mcs = xen_mc_entry(sizeof(*u));
u = mcs.args;
/* ptep might be kmapped when using 32-bit HIGHPTE */
u->ptr = arbitrary_virt_to_machine(ptep).maddr;
u->val = pte_val_ma(pteval);
MULTI_mmu_update(mcs.mc, mcs.args, 1, NULL, DOMID_IO);
xen_mc_issue(PARAVIRT_LAZY_MMU);
}
static void xen_extend_mmu_update(const struct mmu_update *update)
{
struct multicall_space mcs;
@ -453,6 +477,11 @@ void set_pte_mfn(unsigned long vaddr, unsigned long mfn, pgprot_t flags)
void xen_set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pteval)
{
if (xen_iomap_pte(pteval)) {
xen_set_iomap_pte(ptep, pteval);
goto out;
}
ADD_STATS(set_pte_at, 1);
// ADD_STATS(set_pte_at_pinned, xen_page_pinned(ptep));
ADD_STATS(set_pte_at_current, mm == current->mm);
@ -523,8 +552,25 @@ static pteval_t pte_pfn_to_mfn(pteval_t val)
return val;
}
static pteval_t iomap_pte(pteval_t val)
{
if (val & _PAGE_PRESENT) {
unsigned long pfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT;
pteval_t flags = val & PTE_FLAGS_MASK;
/* We assume the pte frame number is a MFN, so
just use it as-is. */
val = ((pteval_t)pfn << PAGE_SHIFT) | flags;
}
return val;
}
pteval_t xen_pte_val(pte_t pte)
{
if (xen_initial_domain() && (pte.pte & _PAGE_IOMAP))
return pte.pte;
return pte_mfn_to_pfn(pte.pte);
}
PV_CALLEE_SAVE_REGS_THUNK(xen_pte_val);
@ -537,7 +583,11 @@ PV_CALLEE_SAVE_REGS_THUNK(xen_pgd_val);
pte_t xen_make_pte(pteval_t pte)
{
pte = pte_pfn_to_mfn(pte);
if (unlikely(xen_initial_domain() && (pte & _PAGE_IOMAP)))
pte = iomap_pte(pte);
else
pte = pte_pfn_to_mfn(pte);
return native_make_pte(pte);
}
PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte);
@ -593,6 +643,11 @@ void xen_set_pud(pud_t *ptr, pud_t val)
void xen_set_pte(pte_t *ptep, pte_t pte)
{
if (xen_iomap_pte(pte)) {
xen_set_iomap_pte(ptep, pte);
return;
}
ADD_STATS(pte_update, 1);
// ADD_STATS(pte_update_pinned, xen_page_pinned(ptep));
ADD_STATS(pte_update_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU);
@ -609,6 +664,11 @@ void xen_set_pte(pte_t *ptep, pte_t pte)
#ifdef CONFIG_X86_PAE
void xen_set_pte_atomic(pte_t *ptep, pte_t pte)
{
if (xen_iomap_pte(pte)) {
xen_set_iomap_pte(ptep, pte);
return;
}
set_64bit((u64 *)ptep, native_pte_val(pte));
}
@ -1811,9 +1871,16 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot)
pte = pfn_pte(phys, prot);
break;
default:
case FIX_PARAVIRT_BOOTMAP:
/* This is an MFN, but it isn't an IO mapping from the
IO domain */
pte = mfn_pte(phys, prot);
break;
default:
/* By default, set_fixmap is used for hardware mappings */
pte = mfn_pte(phys, __pgprot(pgprot_val(prot) | _PAGE_IOMAP));
break;
}
__native_set_fixmap(idx, pte);