From 1c70e9bd832642b712181e32d1bbf2436058a3df Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 30 Jan 2008 13:33:39 +0100 Subject: [PATCH] xen: deal with pmd being allocated/freed Deal properly with pmd-level pages being allocated and freed dynamically. We can handle them more or less the same as pte pages. Also, deal with early_ioremap pagetable manipulations. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/xen/enlighten.c | 30 +++++++++++++++++++++++++----- 1 file changed, 25 insertions(+), 5 deletions(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 845b4fd9446..de647bc6e74 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -658,6 +658,13 @@ static __init void xen_alloc_pt_init(struct mm_struct *mm, u32 pfn) make_lowmem_page_readonly(__va(PFN_PHYS(pfn))); } +/* Early release_pt assumes that all pts are pinned, since there's + only init_mm and anything attached to that is pinned. */ +static void xen_release_pt_init(u32 pfn) +{ + make_lowmem_page_readwrite(__va(PFN_PHYS(pfn))); +} + static void pin_pagetable_pfn(unsigned level, unsigned long pfn) { struct mmuext_op op; @@ -669,7 +676,7 @@ static void pin_pagetable_pfn(unsigned level, unsigned long pfn) /* This needs to make sure the new pte page is pinned iff its being attached to a pinned pagetable. */ -static void xen_alloc_pt(struct mm_struct *mm, u32 pfn) +static void xen_alloc_ptpage(struct mm_struct *mm, u32 pfn, unsigned level) { struct page *page = pfn_to_page(pfn); @@ -678,7 +685,7 @@ static void xen_alloc_pt(struct mm_struct *mm, u32 pfn) if (!PageHighMem(page)) { make_lowmem_page_readonly(__va(PFN_PHYS(pfn))); - pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE, pfn); + pin_pagetable_pfn(level, pfn); } else /* make sure there are no stray mappings of this page */ @@ -686,6 +693,16 @@ static void xen_alloc_pt(struct mm_struct *mm, u32 pfn) } } +static void xen_alloc_pt(struct mm_struct *mm, u32 pfn) +{ + xen_alloc_ptpage(mm, pfn, MMUEXT_PIN_L1_TABLE); +} + +static void xen_alloc_pd(struct mm_struct *mm, u32 pfn) +{ + xen_alloc_ptpage(mm, pfn, MMUEXT_PIN_L2_TABLE); +} + /* This should never happen until we're OK to use struct page */ static void xen_release_pt(u32 pfn) { @@ -788,6 +805,9 @@ static __init void xen_pagetable_setup_done(pgd_t *base) /* This will work as long as patching hasn't happened yet (which it hasn't) */ pv_mmu_ops.alloc_pt = xen_alloc_pt; + pv_mmu_ops.alloc_pd = xen_alloc_pd; + pv_mmu_ops.release_pt = xen_release_pt; + pv_mmu_ops.release_pd = xen_release_pt; pv_mmu_ops.set_pte = xen_set_pte; if (!xen_feature(XENFEAT_auto_translated_physmap)) { @@ -1011,10 +1031,10 @@ static const struct pv_mmu_ops xen_mmu_ops __initdata = { .pte_update_defer = paravirt_nop, .alloc_pt = xen_alloc_pt_init, - .release_pt = xen_release_pt, - .alloc_pd = paravirt_nop, + .release_pt = xen_release_pt_init, + .alloc_pd = xen_alloc_pt_init, .alloc_pd_clone = paravirt_nop, - .release_pd = paravirt_nop, + .release_pd = xen_release_pt_init, #ifdef CONFIG_HIGHPTE .kmap_atomic_pte = xen_kmap_atomic_pte, -- 2.41.1