x86/paravirt: add a pgd_alloc/free hooks

Add hooks which are called at pgd_alloc/free time.  The pgd_alloc hook
may return an error code, which if non-zero, causes the pgd allocation
to be failed.  The hooks may be used to allocate/free auxillary
per-pgd information.

also fix:

> * Ingo Molnar <mingo@elte.hu> wrote:
>
>  include/asm/pgalloc.h: In function ‘paravirt_pgd_free':
>  include/asm/pgalloc.h:14: error: parameter name omitted
>  arch/x86/kernel/entry_64.S: In file included from
>  arch/x86/kernel/traps_64.c:51:include/asm/pgalloc.h: In function ‘paravirt_pgd_free':
>  include/asm/pgalloc.h:14: error: parameter name omitted

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: xen-devel <xen-devel@lists.xensource.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Jeremy Fitzhardinge 2008-06-25 00:19:12 -04:00 committed by Ingo Molnar
parent 67350a5c45
commit eba0045ff8
5 changed files with 38 additions and 6 deletions

View File

@ -30,6 +30,7 @@
#include <asm/setup.h>
#include <asm/arch_hooks.h>
#include <asm/time.h>
#include <asm/pgalloc.h>
#include <asm/irq.h>
#include <asm/delay.h>
#include <asm/fixmap.h>
@ -366,6 +367,9 @@ struct pv_mmu_ops pv_mmu_ops = {
.flush_tlb_single = native_flush_tlb_single,
.flush_tlb_others = native_flush_tlb_others,
.pgd_alloc = __paravirt_pgd_alloc,
.pgd_free = paravirt_nop,
.alloc_pte = paravirt_nop,
.alloc_pmd = paravirt_nop,
.alloc_pmd_clone = paravirt_nop,

View File

@ -215,13 +215,15 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
/* so that alloc_pmd can use it */
mm->pgd = pgd;
if (pgd)
if (pgd) {
pgd_ctor(pgd);
if (pgd && !pgd_prepopulate_pmd(mm, pgd)) {
pgd_dtor(pgd);
free_page((unsigned long)pgd);
pgd = NULL;
if (paravirt_pgd_alloc(mm) != 0 ||
!pgd_prepopulate_pmd(mm, pgd)) {
pgd_dtor(pgd);
free_page((unsigned long)pgd);
pgd = NULL;
}
}
return pgd;
@ -231,6 +233,7 @@ void pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
pgd_mop_up_pmds(mm, pgd);
pgd_dtor(pgd);
paravirt_pgd_free(mm, pgd);
free_page((unsigned long)pgd);
}

View File

@ -45,6 +45,7 @@
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
#include <asm/reboot.h>
#include <asm/pgalloc.h>
#include "xen-ops.h"
#include "mmu.h"
@ -1153,6 +1154,9 @@ static const struct pv_mmu_ops xen_mmu_ops __initdata = {
.pte_update = paravirt_nop,
.pte_update_defer = paravirt_nop,
.pgd_alloc = __paravirt_pgd_alloc,
.pgd_free = paravirt_nop,
.alloc_pte = xen_alloc_pte_init,
.release_pte = xen_release_pte_init,
.alloc_pmd = xen_alloc_pte_init,

View File

@ -219,7 +219,14 @@ struct pv_mmu_ops {
void (*flush_tlb_others)(const cpumask_t *cpus, struct mm_struct *mm,
unsigned long va);
/* Hooks for allocating/releasing pagetable pages */
/* Hooks for allocating and freeing a pagetable top-level */
int (*pgd_alloc)(struct mm_struct *mm);
void (*pgd_free)(struct mm_struct *mm, pgd_t *pgd);
/*
* Hooks for allocating/releasing pagetable pages when they're
* attached to a pagetable
*/
void (*alloc_pte)(struct mm_struct *mm, u32 pfn);
void (*alloc_pmd)(struct mm_struct *mm, u32 pfn);
void (*alloc_pmd_clone)(u32 pfn, u32 clonepfn, u32 start, u32 count);
@ -925,6 +932,16 @@ static inline void flush_tlb_others(cpumask_t cpumask, struct mm_struct *mm,
PVOP_VCALL3(pv_mmu_ops.flush_tlb_others, &cpumask, mm, va);
}
static inline int paravirt_pgd_alloc(struct mm_struct *mm)
{
return PVOP_CALL1(int, pv_mmu_ops.pgd_alloc, mm);
}
static inline void paravirt_pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
PVOP_VCALL2(pv_mmu_ops.pgd_free, mm, pgd);
}
static inline void paravirt_alloc_pte(struct mm_struct *mm, unsigned pfn)
{
PVOP_VCALL2(pv_mmu_ops.alloc_pte, mm, pfn);

View File

@ -5,9 +5,13 @@
#include <linux/mm.h> /* for struct page */
#include <linux/pagemap.h>
static inline int __paravirt_pgd_alloc(struct mm_struct *mm) { return 0; }
#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
#else
#define paravirt_pgd_alloc(mm) __paravirt_pgd_alloc(mm)
static inline void paravirt_pgd_free(struct mm_struct *mm, pgd_t *pgd) {}
static inline void paravirt_alloc_pte(struct mm_struct *mm, unsigned long pfn) {}
static inline void paravirt_alloc_pmd(struct mm_struct *mm, unsigned long pfn) {}
static inline void paravirt_alloc_pmd_clone(unsigned long pfn, unsigned long clonepfn,