![Linus Torvalds](/assets/img/avatar_default.png)
* 'for-rc1/xen/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen: xen: add FIX_TEXT_POKE to fixmap xen: honour VCPU availability on boot xen: clean up gate trap/interrupt constants xen: set _PAGE_NX in __supported_pte_mask before pagetable construction xen: resume interrupts before system devices. xen/mmu: weaken flush_tlb_other test xen/mmu: some early pagetable cleanups Xen: Add virt_to_pfn helper function x86-64: remove PGE from must-have feature list xen: mask XSAVE from cpuid NULL noise: arch/x86/xen/smp.c xen: remove xen_load_gdt debug xen: make xen_load_gdt simpler xen: clean up xen_load_gdt xen: split construction of p2m mfn tables from registration xen: separate p2m allocation from setting xen: disable preempt for leave_lazy_mmu
2015 lines
49 KiB
C
2015 lines
49 KiB
C
/*
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* Xen mmu operations
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*
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* This file contains the various mmu fetch and update operations.
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* The most important job they must perform is the mapping between the
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* domain's pfn and the overall machine mfns.
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*
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* Xen allows guests to directly update the pagetable, in a controlled
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* fashion. In other words, the guest modifies the same pagetable
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* that the CPU actually uses, which eliminates the overhead of having
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* a separate shadow pagetable.
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*
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* In order to allow this, it falls on the guest domain to map its
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* notion of a "physical" pfn - which is just a domain-local linear
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* address - into a real "machine address" which the CPU's MMU can
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* use.
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*
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* A pgd_t/pmd_t/pte_t will typically contain an mfn, and so can be
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* inserted directly into the pagetable. When creating a new
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* pte/pmd/pgd, it converts the passed pfn into an mfn. Conversely,
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* when reading the content back with __(pgd|pmd|pte)_val, it converts
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* the mfn back into a pfn.
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*
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* The other constraint is that all pages which make up a pagetable
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* must be mapped read-only in the guest. This prevents uncontrolled
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* guest updates to the pagetable. Xen strictly enforces this, and
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* will disallow any pagetable update which will end up mapping a
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* pagetable page RW, and will disallow using any writable page as a
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* pagetable.
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*
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* Naively, when loading %cr3 with the base of a new pagetable, Xen
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* would need to validate the whole pagetable before going on.
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* Naturally, this is quite slow. The solution is to "pin" a
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* pagetable, which enforces all the constraints on the pagetable even
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* when it is not actively in use. This menas that Xen can be assured
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* that it is still valid when you do load it into %cr3, and doesn't
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* need to revalidate it.
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*
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* Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
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*/
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#include <linux/sched.h>
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#include <linux/highmem.h>
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#include <linux/debugfs.h>
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#include <linux/bug.h>
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#include <asm/pgtable.h>
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#include <asm/tlbflush.h>
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#include <asm/fixmap.h>
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#include <asm/mmu_context.h>
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#include <asm/setup.h>
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#include <asm/paravirt.h>
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#include <asm/linkage.h>
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#include <asm/xen/hypercall.h>
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#include <asm/xen/hypervisor.h>
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#include <xen/page.h>
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#include <xen/interface/xen.h>
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#include <xen/interface/version.h>
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#include <xen/hvc-console.h>
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#include "multicalls.h"
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#include "mmu.h"
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#include "debugfs.h"
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#define MMU_UPDATE_HISTO 30
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#ifdef CONFIG_XEN_DEBUG_FS
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static struct {
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u32 pgd_update;
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u32 pgd_update_pinned;
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u32 pgd_update_batched;
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u32 pud_update;
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u32 pud_update_pinned;
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u32 pud_update_batched;
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u32 pmd_update;
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u32 pmd_update_pinned;
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u32 pmd_update_batched;
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u32 pte_update;
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u32 pte_update_pinned;
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u32 pte_update_batched;
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u32 mmu_update;
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u32 mmu_update_extended;
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u32 mmu_update_histo[MMU_UPDATE_HISTO];
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u32 prot_commit;
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u32 prot_commit_batched;
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u32 set_pte_at;
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u32 set_pte_at_batched;
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u32 set_pte_at_pinned;
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u32 set_pte_at_current;
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u32 set_pte_at_kernel;
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} mmu_stats;
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static u8 zero_stats;
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static inline void check_zero(void)
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{
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if (unlikely(zero_stats)) {
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memset(&mmu_stats, 0, sizeof(mmu_stats));
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zero_stats = 0;
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}
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}
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#define ADD_STATS(elem, val) \
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do { check_zero(); mmu_stats.elem += (val); } while(0)
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#else /* !CONFIG_XEN_DEBUG_FS */
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#define ADD_STATS(elem, val) do { (void)(val); } while(0)
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#endif /* CONFIG_XEN_DEBUG_FS */
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/*
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* Identity map, in addition to plain kernel map. This needs to be
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* large enough to allocate page table pages to allocate the rest.
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* Each page can map 2MB.
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*/
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static pte_t level1_ident_pgt[PTRS_PER_PTE * 4] __page_aligned_bss;
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#ifdef CONFIG_X86_64
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/* l3 pud for userspace vsyscall mapping */
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static pud_t level3_user_vsyscall[PTRS_PER_PUD] __page_aligned_bss;
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#endif /* CONFIG_X86_64 */
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/*
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* Note about cr3 (pagetable base) values:
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*
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* xen_cr3 contains the current logical cr3 value; it contains the
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* last set cr3. This may not be the current effective cr3, because
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* its update may be being lazily deferred. However, a vcpu looking
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* at its own cr3 can use this value knowing that it everything will
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* be self-consistent.
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*
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* xen_current_cr3 contains the actual vcpu cr3; it is set once the
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* hypercall to set the vcpu cr3 is complete (so it may be a little
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* out of date, but it will never be set early). If one vcpu is
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* looking at another vcpu's cr3 value, it should use this variable.
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*/
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DEFINE_PER_CPU(unsigned long, xen_cr3); /* cr3 stored as physaddr */
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DEFINE_PER_CPU(unsigned long, xen_current_cr3); /* actual vcpu cr3 */
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/*
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* Just beyond the highest usermode address. STACK_TOP_MAX has a
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* redzone above it, so round it up to a PGD boundary.
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*/
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#define USER_LIMIT ((STACK_TOP_MAX + PGDIR_SIZE - 1) & PGDIR_MASK)
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#define P2M_ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(unsigned long))
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#define TOP_ENTRIES (MAX_DOMAIN_PAGES / P2M_ENTRIES_PER_PAGE)
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/* Placeholder for holes in the address space */
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static unsigned long p2m_missing[P2M_ENTRIES_PER_PAGE] __page_aligned_data =
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{ [ 0 ... P2M_ENTRIES_PER_PAGE-1 ] = ~0UL };
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/* Array of pointers to pages containing p2m entries */
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static unsigned long *p2m_top[TOP_ENTRIES] __page_aligned_data =
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{ [ 0 ... TOP_ENTRIES - 1] = &p2m_missing[0] };
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/* Arrays of p2m arrays expressed in mfns used for save/restore */
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static unsigned long p2m_top_mfn[TOP_ENTRIES] __page_aligned_bss;
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static unsigned long p2m_top_mfn_list[TOP_ENTRIES / P2M_ENTRIES_PER_PAGE]
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__page_aligned_bss;
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static inline unsigned p2m_top_index(unsigned long pfn)
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{
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BUG_ON(pfn >= MAX_DOMAIN_PAGES);
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return pfn / P2M_ENTRIES_PER_PAGE;
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}
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static inline unsigned p2m_index(unsigned long pfn)
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{
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return pfn % P2M_ENTRIES_PER_PAGE;
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}
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/* Build the parallel p2m_top_mfn structures */
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static void __init xen_build_mfn_list_list(void)
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{
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unsigned pfn, idx;
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for (pfn = 0; pfn < MAX_DOMAIN_PAGES; pfn += P2M_ENTRIES_PER_PAGE) {
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unsigned topidx = p2m_top_index(pfn);
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p2m_top_mfn[topidx] = virt_to_mfn(p2m_top[topidx]);
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}
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for (idx = 0; idx < ARRAY_SIZE(p2m_top_mfn_list); idx++) {
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unsigned topidx = idx * P2M_ENTRIES_PER_PAGE;
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p2m_top_mfn_list[idx] = virt_to_mfn(&p2m_top_mfn[topidx]);
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}
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}
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void xen_setup_mfn_list_list(void)
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{
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BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info);
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HYPERVISOR_shared_info->arch.pfn_to_mfn_frame_list_list =
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virt_to_mfn(p2m_top_mfn_list);
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HYPERVISOR_shared_info->arch.max_pfn = xen_start_info->nr_pages;
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}
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/* Set up p2m_top to point to the domain-builder provided p2m pages */
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void __init xen_build_dynamic_phys_to_machine(void)
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{
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unsigned long *mfn_list = (unsigned long *)xen_start_info->mfn_list;
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unsigned long max_pfn = min(MAX_DOMAIN_PAGES, xen_start_info->nr_pages);
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unsigned pfn;
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for (pfn = 0; pfn < max_pfn; pfn += P2M_ENTRIES_PER_PAGE) {
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unsigned topidx = p2m_top_index(pfn);
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p2m_top[topidx] = &mfn_list[pfn];
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}
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xen_build_mfn_list_list();
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}
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unsigned long get_phys_to_machine(unsigned long pfn)
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{
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unsigned topidx, idx;
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if (unlikely(pfn >= MAX_DOMAIN_PAGES))
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return INVALID_P2M_ENTRY;
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topidx = p2m_top_index(pfn);
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idx = p2m_index(pfn);
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return p2m_top[topidx][idx];
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}
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EXPORT_SYMBOL_GPL(get_phys_to_machine);
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/* install a new p2m_top page */
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bool install_p2mtop_page(unsigned long pfn, unsigned long *p)
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{
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unsigned topidx = p2m_top_index(pfn);
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unsigned long **pfnp, *mfnp;
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unsigned i;
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pfnp = &p2m_top[topidx];
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mfnp = &p2m_top_mfn[topidx];
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for (i = 0; i < P2M_ENTRIES_PER_PAGE; i++)
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p[i] = INVALID_P2M_ENTRY;
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if (cmpxchg(pfnp, p2m_missing, p) == p2m_missing) {
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*mfnp = virt_to_mfn(p);
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return true;
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}
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return false;
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}
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static void alloc_p2m(unsigned long pfn)
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{
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unsigned long *p;
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p = (void *)__get_free_page(GFP_KERNEL | __GFP_NOFAIL);
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BUG_ON(p == NULL);
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if (!install_p2mtop_page(pfn, p))
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free_page((unsigned long)p);
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}
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/* Try to install p2m mapping; fail if intermediate bits missing */
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bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn)
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{
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unsigned topidx, idx;
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if (unlikely(pfn >= MAX_DOMAIN_PAGES)) {
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BUG_ON(mfn != INVALID_P2M_ENTRY);
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return true;
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}
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topidx = p2m_top_index(pfn);
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if (p2m_top[topidx] == p2m_missing) {
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if (mfn == INVALID_P2M_ENTRY)
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return true;
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return false;
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}
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idx = p2m_index(pfn);
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p2m_top[topidx][idx] = mfn;
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return true;
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}
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void set_phys_to_machine(unsigned long pfn, unsigned long mfn)
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{
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if (unlikely(xen_feature(XENFEAT_auto_translated_physmap))) {
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BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY);
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return;
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}
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if (unlikely(!__set_phys_to_machine(pfn, mfn))) {
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alloc_p2m(pfn);
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if (!__set_phys_to_machine(pfn, mfn))
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BUG();
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}
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}
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unsigned long arbitrary_virt_to_mfn(void *vaddr)
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{
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xmaddr_t maddr = arbitrary_virt_to_machine(vaddr);
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return PFN_DOWN(maddr.maddr);
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}
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xmaddr_t arbitrary_virt_to_machine(void *vaddr)
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{
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unsigned long address = (unsigned long)vaddr;
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unsigned int level;
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pte_t *pte;
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unsigned offset;
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/*
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* if the PFN is in the linear mapped vaddr range, we can just use
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* the (quick) virt_to_machine() p2m lookup
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*/
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if (virt_addr_valid(vaddr))
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return virt_to_machine(vaddr);
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/* otherwise we have to do a (slower) full page-table walk */
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pte = lookup_address(address, &level);
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BUG_ON(pte == NULL);
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offset = address & ~PAGE_MASK;
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return XMADDR(((phys_addr_t)pte_mfn(*pte) << PAGE_SHIFT) + offset);
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}
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void make_lowmem_page_readonly(void *vaddr)
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{
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pte_t *pte, ptev;
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unsigned long address = (unsigned long)vaddr;
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unsigned int level;
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pte = lookup_address(address, &level);
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BUG_ON(pte == NULL);
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ptev = pte_wrprotect(*pte);
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if (HYPERVISOR_update_va_mapping(address, ptev, 0))
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BUG();
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}
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void make_lowmem_page_readwrite(void *vaddr)
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{
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pte_t *pte, ptev;
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unsigned long address = (unsigned long)vaddr;
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unsigned int level;
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pte = lookup_address(address, &level);
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BUG_ON(pte == NULL);
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ptev = pte_mkwrite(*pte);
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if (HYPERVISOR_update_va_mapping(address, ptev, 0))
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BUG();
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}
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static bool xen_page_pinned(void *ptr)
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{
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struct page *page = virt_to_page(ptr);
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return PagePinned(page);
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}
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static void xen_extend_mmu_update(const struct mmu_update *update)
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{
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struct multicall_space mcs;
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struct mmu_update *u;
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mcs = xen_mc_extend_args(__HYPERVISOR_mmu_update, sizeof(*u));
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if (mcs.mc != NULL) {
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ADD_STATS(mmu_update_extended, 1);
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ADD_STATS(mmu_update_histo[mcs.mc->args[1]], -1);
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mcs.mc->args[1]++;
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if (mcs.mc->args[1] < MMU_UPDATE_HISTO)
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ADD_STATS(mmu_update_histo[mcs.mc->args[1]], 1);
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else
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ADD_STATS(mmu_update_histo[0], 1);
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} else {
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ADD_STATS(mmu_update, 1);
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mcs = __xen_mc_entry(sizeof(*u));
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MULTI_mmu_update(mcs.mc, mcs.args, 1, NULL, DOMID_SELF);
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ADD_STATS(mmu_update_histo[1], 1);
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}
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u = mcs.args;
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*u = *update;
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}
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void xen_set_pmd_hyper(pmd_t *ptr, pmd_t val)
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{
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struct mmu_update u;
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preempt_disable();
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xen_mc_batch();
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/* ptr may be ioremapped for 64-bit pagetable setup */
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u.ptr = arbitrary_virt_to_machine(ptr).maddr;
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u.val = pmd_val_ma(val);
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xen_extend_mmu_update(&u);
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ADD_STATS(pmd_update_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU);
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xen_mc_issue(PARAVIRT_LAZY_MMU);
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preempt_enable();
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}
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void xen_set_pmd(pmd_t *ptr, pmd_t val)
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{
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ADD_STATS(pmd_update, 1);
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/* If page is not pinned, we can just update the entry
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directly */
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if (!xen_page_pinned(ptr)) {
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*ptr = val;
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return;
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}
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ADD_STATS(pmd_update_pinned, 1);
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xen_set_pmd_hyper(ptr, val);
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}
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/*
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* Associate a virtual page frame with a given physical page frame
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* and protection flags for that frame.
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*/
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void set_pte_mfn(unsigned long vaddr, unsigned long mfn, pgprot_t flags)
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{
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set_pte_vaddr(vaddr, mfn_pte(mfn, flags));
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}
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void xen_set_pte_at(struct mm_struct *mm, unsigned long addr,
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pte_t *ptep, pte_t pteval)
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{
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/* updates to init_mm may be done without lock */
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if (mm == &init_mm)
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preempt_disable();
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ADD_STATS(set_pte_at, 1);
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// ADD_STATS(set_pte_at_pinned, xen_page_pinned(ptep));
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ADD_STATS(set_pte_at_current, mm == current->mm);
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ADD_STATS(set_pte_at_kernel, mm == &init_mm);
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if (mm == current->mm || mm == &init_mm) {
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if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) {
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struct multicall_space mcs;
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mcs = xen_mc_entry(0);
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MULTI_update_va_mapping(mcs.mc, addr, pteval, 0);
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ADD_STATS(set_pte_at_batched, 1);
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xen_mc_issue(PARAVIRT_LAZY_MMU);
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goto out;
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} else
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if (HYPERVISOR_update_va_mapping(addr, pteval, 0) == 0)
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goto out;
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}
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xen_set_pte(ptep, pteval);
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out:
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if (mm == &init_mm)
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preempt_enable();
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}
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|
|
pte_t xen_ptep_modify_prot_start(struct mm_struct *mm,
|
|
unsigned long addr, pte_t *ptep)
|
|
{
|
|
/* Just return the pte as-is. We preserve the bits on commit */
|
|
return *ptep;
|
|
}
|
|
|
|
void xen_ptep_modify_prot_commit(struct mm_struct *mm, unsigned long addr,
|
|
pte_t *ptep, pte_t pte)
|
|
{
|
|
struct mmu_update u;
|
|
|
|
xen_mc_batch();
|
|
|
|
u.ptr = arbitrary_virt_to_machine(ptep).maddr | MMU_PT_UPDATE_PRESERVE_AD;
|
|
u.val = pte_val_ma(pte);
|
|
xen_extend_mmu_update(&u);
|
|
|
|
ADD_STATS(prot_commit, 1);
|
|
ADD_STATS(prot_commit_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU);
|
|
|
|
xen_mc_issue(PARAVIRT_LAZY_MMU);
|
|
}
|
|
|
|
/* Assume pteval_t is equivalent to all the other *val_t types. */
|
|
static pteval_t pte_mfn_to_pfn(pteval_t val)
|
|
{
|
|
if (val & _PAGE_PRESENT) {
|
|
unsigned long mfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT;
|
|
pteval_t flags = val & PTE_FLAGS_MASK;
|
|
val = ((pteval_t)mfn_to_pfn(mfn) << PAGE_SHIFT) | flags;
|
|
}
|
|
|
|
return val;
|
|
}
|
|
|
|
static pteval_t pte_pfn_to_mfn(pteval_t val)
|
|
{
|
|
if (val & _PAGE_PRESENT) {
|
|
unsigned long pfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT;
|
|
pteval_t flags = val & PTE_FLAGS_MASK;
|
|
val = ((pteval_t)pfn_to_mfn(pfn) << PAGE_SHIFT) | flags;
|
|
}
|
|
|
|
return val;
|
|
}
|
|
|
|
pteval_t xen_pte_val(pte_t pte)
|
|
{
|
|
return pte_mfn_to_pfn(pte.pte);
|
|
}
|
|
PV_CALLEE_SAVE_REGS_THUNK(xen_pte_val);
|
|
|
|
pgdval_t xen_pgd_val(pgd_t pgd)
|
|
{
|
|
return pte_mfn_to_pfn(pgd.pgd);
|
|
}
|
|
PV_CALLEE_SAVE_REGS_THUNK(xen_pgd_val);
|
|
|
|
pte_t xen_make_pte(pteval_t pte)
|
|
{
|
|
pte = pte_pfn_to_mfn(pte);
|
|
return native_make_pte(pte);
|
|
}
|
|
PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte);
|
|
|
|
pgd_t xen_make_pgd(pgdval_t pgd)
|
|
{
|
|
pgd = pte_pfn_to_mfn(pgd);
|
|
return native_make_pgd(pgd);
|
|
}
|
|
PV_CALLEE_SAVE_REGS_THUNK(xen_make_pgd);
|
|
|
|
pmdval_t xen_pmd_val(pmd_t pmd)
|
|
{
|
|
return pte_mfn_to_pfn(pmd.pmd);
|
|
}
|
|
PV_CALLEE_SAVE_REGS_THUNK(xen_pmd_val);
|
|
|
|
void xen_set_pud_hyper(pud_t *ptr, pud_t val)
|
|
{
|
|
struct mmu_update u;
|
|
|
|
preempt_disable();
|
|
|
|
xen_mc_batch();
|
|
|
|
/* ptr may be ioremapped for 64-bit pagetable setup */
|
|
u.ptr = arbitrary_virt_to_machine(ptr).maddr;
|
|
u.val = pud_val_ma(val);
|
|
xen_extend_mmu_update(&u);
|
|
|
|
ADD_STATS(pud_update_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU);
|
|
|
|
xen_mc_issue(PARAVIRT_LAZY_MMU);
|
|
|
|
preempt_enable();
|
|
}
|
|
|
|
void xen_set_pud(pud_t *ptr, pud_t val)
|
|
{
|
|
ADD_STATS(pud_update, 1);
|
|
|
|
/* If page is not pinned, we can just update the entry
|
|
directly */
|
|
if (!xen_page_pinned(ptr)) {
|
|
*ptr = val;
|
|
return;
|
|
}
|
|
|
|
ADD_STATS(pud_update_pinned, 1);
|
|
|
|
xen_set_pud_hyper(ptr, val);
|
|
}
|
|
|
|
void xen_set_pte(pte_t *ptep, pte_t pte)
|
|
{
|
|
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);
|
|
|
|
#ifdef CONFIG_X86_PAE
|
|
ptep->pte_high = pte.pte_high;
|
|
smp_wmb();
|
|
ptep->pte_low = pte.pte_low;
|
|
#else
|
|
*ptep = pte;
|
|
#endif
|
|
}
|
|
|
|
#ifdef CONFIG_X86_PAE
|
|
void xen_set_pte_atomic(pte_t *ptep, pte_t pte)
|
|
{
|
|
set_64bit((u64 *)ptep, native_pte_val(pte));
|
|
}
|
|
|
|
void xen_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
|
|
{
|
|
ptep->pte_low = 0;
|
|
smp_wmb(); /* make sure low gets written first */
|
|
ptep->pte_high = 0;
|
|
}
|
|
|
|
void xen_pmd_clear(pmd_t *pmdp)
|
|
{
|
|
set_pmd(pmdp, __pmd(0));
|
|
}
|
|
#endif /* CONFIG_X86_PAE */
|
|
|
|
pmd_t xen_make_pmd(pmdval_t pmd)
|
|
{
|
|
pmd = pte_pfn_to_mfn(pmd);
|
|
return native_make_pmd(pmd);
|
|
}
|
|
PV_CALLEE_SAVE_REGS_THUNK(xen_make_pmd);
|
|
|
|
#if PAGETABLE_LEVELS == 4
|
|
pudval_t xen_pud_val(pud_t pud)
|
|
{
|
|
return pte_mfn_to_pfn(pud.pud);
|
|
}
|
|
PV_CALLEE_SAVE_REGS_THUNK(xen_pud_val);
|
|
|
|
pud_t xen_make_pud(pudval_t pud)
|
|
{
|
|
pud = pte_pfn_to_mfn(pud);
|
|
|
|
return native_make_pud(pud);
|
|
}
|
|
PV_CALLEE_SAVE_REGS_THUNK(xen_make_pud);
|
|
|
|
pgd_t *xen_get_user_pgd(pgd_t *pgd)
|
|
{
|
|
pgd_t *pgd_page = (pgd_t *)(((unsigned long)pgd) & PAGE_MASK);
|
|
unsigned offset = pgd - pgd_page;
|
|
pgd_t *user_ptr = NULL;
|
|
|
|
if (offset < pgd_index(USER_LIMIT)) {
|
|
struct page *page = virt_to_page(pgd_page);
|
|
user_ptr = (pgd_t *)page->private;
|
|
if (user_ptr)
|
|
user_ptr += offset;
|
|
}
|
|
|
|
return user_ptr;
|
|
}
|
|
|
|
static void __xen_set_pgd_hyper(pgd_t *ptr, pgd_t val)
|
|
{
|
|
struct mmu_update u;
|
|
|
|
u.ptr = virt_to_machine(ptr).maddr;
|
|
u.val = pgd_val_ma(val);
|
|
xen_extend_mmu_update(&u);
|
|
}
|
|
|
|
/*
|
|
* Raw hypercall-based set_pgd, intended for in early boot before
|
|
* there's a page structure. This implies:
|
|
* 1. The only existing pagetable is the kernel's
|
|
* 2. It is always pinned
|
|
* 3. It has no user pagetable attached to it
|
|
*/
|
|
void __init xen_set_pgd_hyper(pgd_t *ptr, pgd_t val)
|
|
{
|
|
preempt_disable();
|
|
|
|
xen_mc_batch();
|
|
|
|
__xen_set_pgd_hyper(ptr, val);
|
|
|
|
xen_mc_issue(PARAVIRT_LAZY_MMU);
|
|
|
|
preempt_enable();
|
|
}
|
|
|
|
void xen_set_pgd(pgd_t *ptr, pgd_t val)
|
|
{
|
|
pgd_t *user_ptr = xen_get_user_pgd(ptr);
|
|
|
|
ADD_STATS(pgd_update, 1);
|
|
|
|
/* If page is not pinned, we can just update the entry
|
|
directly */
|
|
if (!xen_page_pinned(ptr)) {
|
|
*ptr = val;
|
|
if (user_ptr) {
|
|
WARN_ON(xen_page_pinned(user_ptr));
|
|
*user_ptr = val;
|
|
}
|
|
return;
|
|
}
|
|
|
|
ADD_STATS(pgd_update_pinned, 1);
|
|
ADD_STATS(pgd_update_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU);
|
|
|
|
/* If it's pinned, then we can at least batch the kernel and
|
|
user updates together. */
|
|
xen_mc_batch();
|
|
|
|
__xen_set_pgd_hyper(ptr, val);
|
|
if (user_ptr)
|
|
__xen_set_pgd_hyper(user_ptr, val);
|
|
|
|
xen_mc_issue(PARAVIRT_LAZY_MMU);
|
|
}
|
|
#endif /* PAGETABLE_LEVELS == 4 */
|
|
|
|
/*
|
|
* (Yet another) pagetable walker. This one is intended for pinning a
|
|
* pagetable. This means that it walks a pagetable and calls the
|
|
* callback function on each page it finds making up the page table,
|
|
* at every level. It walks the entire pagetable, but it only bothers
|
|
* pinning pte pages which are below limit. In the normal case this
|
|
* will be STACK_TOP_MAX, but at boot we need to pin up to
|
|
* FIXADDR_TOP.
|
|
*
|
|
* For 32-bit the important bit is that we don't pin beyond there,
|
|
* because then we start getting into Xen's ptes.
|
|
*
|
|
* For 64-bit, we must skip the Xen hole in the middle of the address
|
|
* space, just after the big x86-64 virtual hole.
|
|
*/
|
|
static int __xen_pgd_walk(struct mm_struct *mm, pgd_t *pgd,
|
|
int (*func)(struct mm_struct *mm, struct page *,
|
|
enum pt_level),
|
|
unsigned long limit)
|
|
{
|
|
int flush = 0;
|
|
unsigned hole_low, hole_high;
|
|
unsigned pgdidx_limit, pudidx_limit, pmdidx_limit;
|
|
unsigned pgdidx, pudidx, pmdidx;
|
|
|
|
/* The limit is the last byte to be touched */
|
|
limit--;
|
|
BUG_ON(limit >= FIXADDR_TOP);
|
|
|
|
if (xen_feature(XENFEAT_auto_translated_physmap))
|
|
return 0;
|
|
|
|
/*
|
|
* 64-bit has a great big hole in the middle of the address
|
|
* space, which contains the Xen mappings. On 32-bit these
|
|
* will end up making a zero-sized hole and so is a no-op.
|
|
*/
|
|
hole_low = pgd_index(USER_LIMIT);
|
|
hole_high = pgd_index(PAGE_OFFSET);
|
|
|
|
pgdidx_limit = pgd_index(limit);
|
|
#if PTRS_PER_PUD > 1
|
|
pudidx_limit = pud_index(limit);
|
|
#else
|
|
pudidx_limit = 0;
|
|
#endif
|
|
#if PTRS_PER_PMD > 1
|
|
pmdidx_limit = pmd_index(limit);
|
|
#else
|
|
pmdidx_limit = 0;
|
|
#endif
|
|
|
|
for (pgdidx = 0; pgdidx <= pgdidx_limit; pgdidx++) {
|
|
pud_t *pud;
|
|
|
|
if (pgdidx >= hole_low && pgdidx < hole_high)
|
|
continue;
|
|
|
|
if (!pgd_val(pgd[pgdidx]))
|
|
continue;
|
|
|
|
pud = pud_offset(&pgd[pgdidx], 0);
|
|
|
|
if (PTRS_PER_PUD > 1) /* not folded */
|
|
flush |= (*func)(mm, virt_to_page(pud), PT_PUD);
|
|
|
|
for (pudidx = 0; pudidx < PTRS_PER_PUD; pudidx++) {
|
|
pmd_t *pmd;
|
|
|
|
if (pgdidx == pgdidx_limit &&
|
|
pudidx > pudidx_limit)
|
|
goto out;
|
|
|
|
if (pud_none(pud[pudidx]))
|
|
continue;
|
|
|
|
pmd = pmd_offset(&pud[pudidx], 0);
|
|
|
|
if (PTRS_PER_PMD > 1) /* not folded */
|
|
flush |= (*func)(mm, virt_to_page(pmd), PT_PMD);
|
|
|
|
for (pmdidx = 0; pmdidx < PTRS_PER_PMD; pmdidx++) {
|
|
struct page *pte;
|
|
|
|
if (pgdidx == pgdidx_limit &&
|
|
pudidx == pudidx_limit &&
|
|
pmdidx > pmdidx_limit)
|
|
goto out;
|
|
|
|
if (pmd_none(pmd[pmdidx]))
|
|
continue;
|
|
|
|
pte = pmd_page(pmd[pmdidx]);
|
|
flush |= (*func)(mm, pte, PT_PTE);
|
|
}
|
|
}
|
|
}
|
|
|
|
out:
|
|
/* Do the top level last, so that the callbacks can use it as
|
|
a cue to do final things like tlb flushes. */
|
|
flush |= (*func)(mm, virt_to_page(pgd), PT_PGD);
|
|
|
|
return flush;
|
|
}
|
|
|
|
static int xen_pgd_walk(struct mm_struct *mm,
|
|
int (*func)(struct mm_struct *mm, struct page *,
|
|
enum pt_level),
|
|
unsigned long limit)
|
|
{
|
|
return __xen_pgd_walk(mm, mm->pgd, func, limit);
|
|
}
|
|
|
|
/* If we're using split pte locks, then take the page's lock and
|
|
return a pointer to it. Otherwise return NULL. */
|
|
static spinlock_t *xen_pte_lock(struct page *page, struct mm_struct *mm)
|
|
{
|
|
spinlock_t *ptl = NULL;
|
|
|
|
#if USE_SPLIT_PTLOCKS
|
|
ptl = __pte_lockptr(page);
|
|
spin_lock_nest_lock(ptl, &mm->page_table_lock);
|
|
#endif
|
|
|
|
return ptl;
|
|
}
|
|
|
|
static void xen_pte_unlock(void *v)
|
|
{
|
|
spinlock_t *ptl = v;
|
|
spin_unlock(ptl);
|
|
}
|
|
|
|
static void xen_do_pin(unsigned level, unsigned long pfn)
|
|
{
|
|
struct mmuext_op *op;
|
|
struct multicall_space mcs;
|
|
|
|
mcs = __xen_mc_entry(sizeof(*op));
|
|
op = mcs.args;
|
|
op->cmd = level;
|
|
op->arg1.mfn = pfn_to_mfn(pfn);
|
|
MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
|
|
}
|
|
|
|
static int xen_pin_page(struct mm_struct *mm, struct page *page,
|
|
enum pt_level level)
|
|
{
|
|
unsigned pgfl = TestSetPagePinned(page);
|
|
int flush;
|
|
|
|
if (pgfl)
|
|
flush = 0; /* already pinned */
|
|
else if (PageHighMem(page))
|
|
/* kmaps need flushing if we found an unpinned
|
|
highpage */
|
|
flush = 1;
|
|
else {
|
|
void *pt = lowmem_page_address(page);
|
|
unsigned long pfn = page_to_pfn(page);
|
|
struct multicall_space mcs = __xen_mc_entry(0);
|
|
spinlock_t *ptl;
|
|
|
|
flush = 0;
|
|
|
|
/*
|
|
* We need to hold the pagetable lock between the time
|
|
* we make the pagetable RO and when we actually pin
|
|
* it. If we don't, then other users may come in and
|
|
* attempt to update the pagetable by writing it,
|
|
* which will fail because the memory is RO but not
|
|
* pinned, so Xen won't do the trap'n'emulate.
|
|
*
|
|
* If we're using split pte locks, we can't hold the
|
|
* entire pagetable's worth of locks during the
|
|
* traverse, because we may wrap the preempt count (8
|
|
* bits). The solution is to mark RO and pin each PTE
|
|
* page while holding the lock. This means the number
|
|
* of locks we end up holding is never more than a
|
|
* batch size (~32 entries, at present).
|
|
*
|
|
* If we're not using split pte locks, we needn't pin
|
|
* the PTE pages independently, because we're
|
|
* protected by the overall pagetable lock.
|
|
*/
|
|
ptl = NULL;
|
|
if (level == PT_PTE)
|
|
ptl = xen_pte_lock(page, mm);
|
|
|
|
MULTI_update_va_mapping(mcs.mc, (unsigned long)pt,
|
|
pfn_pte(pfn, PAGE_KERNEL_RO),
|
|
level == PT_PGD ? UVMF_TLB_FLUSH : 0);
|
|
|
|
if (ptl) {
|
|
xen_do_pin(MMUEXT_PIN_L1_TABLE, pfn);
|
|
|
|
/* Queue a deferred unlock for when this batch
|
|
is completed. */
|
|
xen_mc_callback(xen_pte_unlock, ptl);
|
|
}
|
|
}
|
|
|
|
return flush;
|
|
}
|
|
|
|
/* This is called just after a mm has been created, but it has not
|
|
been used yet. We need to make sure that its pagetable is all
|
|
read-only, and can be pinned. */
|
|
static void __xen_pgd_pin(struct mm_struct *mm, pgd_t *pgd)
|
|
{
|
|
vm_unmap_aliases();
|
|
|
|
xen_mc_batch();
|
|
|
|
if (__xen_pgd_walk(mm, pgd, xen_pin_page, USER_LIMIT)) {
|
|
/* re-enable interrupts for flushing */
|
|
xen_mc_issue(0);
|
|
|
|
kmap_flush_unused();
|
|
|
|
xen_mc_batch();
|
|
}
|
|
|
|
#ifdef CONFIG_X86_64
|
|
{
|
|
pgd_t *user_pgd = xen_get_user_pgd(pgd);
|
|
|
|
xen_do_pin(MMUEXT_PIN_L4_TABLE, PFN_DOWN(__pa(pgd)));
|
|
|
|
if (user_pgd) {
|
|
xen_pin_page(mm, virt_to_page(user_pgd), PT_PGD);
|
|
xen_do_pin(MMUEXT_PIN_L4_TABLE,
|
|
PFN_DOWN(__pa(user_pgd)));
|
|
}
|
|
}
|
|
#else /* CONFIG_X86_32 */
|
|
#ifdef CONFIG_X86_PAE
|
|
/* Need to make sure unshared kernel PMD is pinnable */
|
|
xen_pin_page(mm, pgd_page(pgd[pgd_index(TASK_SIZE)]),
|
|
PT_PMD);
|
|
#endif
|
|
xen_do_pin(MMUEXT_PIN_L3_TABLE, PFN_DOWN(__pa(pgd)));
|
|
#endif /* CONFIG_X86_64 */
|
|
xen_mc_issue(0);
|
|
}
|
|
|
|
static void xen_pgd_pin(struct mm_struct *mm)
|
|
{
|
|
__xen_pgd_pin(mm, mm->pgd);
|
|
}
|
|
|
|
/*
|
|
* On save, we need to pin all pagetables to make sure they get their
|
|
* mfns turned into pfns. Search the list for any unpinned pgds and pin
|
|
* them (unpinned pgds are not currently in use, probably because the
|
|
* process is under construction or destruction).
|
|
*
|
|
* Expected to be called in stop_machine() ("equivalent to taking
|
|
* every spinlock in the system"), so the locking doesn't really
|
|
* matter all that much.
|
|
*/
|
|
void xen_mm_pin_all(void)
|
|
{
|
|
unsigned long flags;
|
|
struct page *page;
|
|
|
|
spin_lock_irqsave(&pgd_lock, flags);
|
|
|
|
list_for_each_entry(page, &pgd_list, lru) {
|
|
if (!PagePinned(page)) {
|
|
__xen_pgd_pin(&init_mm, (pgd_t *)page_address(page));
|
|
SetPageSavePinned(page);
|
|
}
|
|
}
|
|
|
|
spin_unlock_irqrestore(&pgd_lock, flags);
|
|
}
|
|
|
|
/*
|
|
* The init_mm pagetable is really pinned as soon as its created, but
|
|
* that's before we have page structures to store the bits. So do all
|
|
* the book-keeping now.
|
|
*/
|
|
static __init int xen_mark_pinned(struct mm_struct *mm, struct page *page,
|
|
enum pt_level level)
|
|
{
|
|
SetPagePinned(page);
|
|
return 0;
|
|
}
|
|
|
|
static void __init xen_mark_init_mm_pinned(void)
|
|
{
|
|
xen_pgd_walk(&init_mm, xen_mark_pinned, FIXADDR_TOP);
|
|
}
|
|
|
|
static int xen_unpin_page(struct mm_struct *mm, struct page *page,
|
|
enum pt_level level)
|
|
{
|
|
unsigned pgfl = TestClearPagePinned(page);
|
|
|
|
if (pgfl && !PageHighMem(page)) {
|
|
void *pt = lowmem_page_address(page);
|
|
unsigned long pfn = page_to_pfn(page);
|
|
spinlock_t *ptl = NULL;
|
|
struct multicall_space mcs;
|
|
|
|
/*
|
|
* Do the converse to pin_page. If we're using split
|
|
* pte locks, we must be holding the lock for while
|
|
* the pte page is unpinned but still RO to prevent
|
|
* concurrent updates from seeing it in this
|
|
* partially-pinned state.
|
|
*/
|
|
if (level == PT_PTE) {
|
|
ptl = xen_pte_lock(page, mm);
|
|
|
|
if (ptl)
|
|
xen_do_pin(MMUEXT_UNPIN_TABLE, pfn);
|
|
}
|
|
|
|
mcs = __xen_mc_entry(0);
|
|
|
|
MULTI_update_va_mapping(mcs.mc, (unsigned long)pt,
|
|
pfn_pte(pfn, PAGE_KERNEL),
|
|
level == PT_PGD ? UVMF_TLB_FLUSH : 0);
|
|
|
|
if (ptl) {
|
|
/* unlock when batch completed */
|
|
xen_mc_callback(xen_pte_unlock, ptl);
|
|
}
|
|
}
|
|
|
|
return 0; /* never need to flush on unpin */
|
|
}
|
|
|
|
/* Release a pagetables pages back as normal RW */
|
|
static void __xen_pgd_unpin(struct mm_struct *mm, pgd_t *pgd)
|
|
{
|
|
xen_mc_batch();
|
|
|
|
xen_do_pin(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd)));
|
|
|
|
#ifdef CONFIG_X86_64
|
|
{
|
|
pgd_t *user_pgd = xen_get_user_pgd(pgd);
|
|
|
|
if (user_pgd) {
|
|
xen_do_pin(MMUEXT_UNPIN_TABLE,
|
|
PFN_DOWN(__pa(user_pgd)));
|
|
xen_unpin_page(mm, virt_to_page(user_pgd), PT_PGD);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_X86_PAE
|
|
/* Need to make sure unshared kernel PMD is unpinned */
|
|
xen_unpin_page(mm, pgd_page(pgd[pgd_index(TASK_SIZE)]),
|
|
PT_PMD);
|
|
#endif
|
|
|
|
__xen_pgd_walk(mm, pgd, xen_unpin_page, USER_LIMIT);
|
|
|
|
xen_mc_issue(0);
|
|
}
|
|
|
|
static void xen_pgd_unpin(struct mm_struct *mm)
|
|
{
|
|
__xen_pgd_unpin(mm, mm->pgd);
|
|
}
|
|
|
|
/*
|
|
* On resume, undo any pinning done at save, so that the rest of the
|
|
* kernel doesn't see any unexpected pinned pagetables.
|
|
*/
|
|
void xen_mm_unpin_all(void)
|
|
{
|
|
unsigned long flags;
|
|
struct page *page;
|
|
|
|
spin_lock_irqsave(&pgd_lock, flags);
|
|
|
|
list_for_each_entry(page, &pgd_list, lru) {
|
|
if (PageSavePinned(page)) {
|
|
BUG_ON(!PagePinned(page));
|
|
__xen_pgd_unpin(&init_mm, (pgd_t *)page_address(page));
|
|
ClearPageSavePinned(page);
|
|
}
|
|
}
|
|
|
|
spin_unlock_irqrestore(&pgd_lock, flags);
|
|
}
|
|
|
|
void xen_activate_mm(struct mm_struct *prev, struct mm_struct *next)
|
|
{
|
|
spin_lock(&next->page_table_lock);
|
|
xen_pgd_pin(next);
|
|
spin_unlock(&next->page_table_lock);
|
|
}
|
|
|
|
void xen_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
|
|
{
|
|
spin_lock(&mm->page_table_lock);
|
|
xen_pgd_pin(mm);
|
|
spin_unlock(&mm->page_table_lock);
|
|
}
|
|
|
|
|
|
#ifdef CONFIG_SMP
|
|
/* Another cpu may still have their %cr3 pointing at the pagetable, so
|
|
we need to repoint it somewhere else before we can unpin it. */
|
|
static void drop_other_mm_ref(void *info)
|
|
{
|
|
struct mm_struct *mm = info;
|
|
struct mm_struct *active_mm;
|
|
|
|
active_mm = percpu_read(cpu_tlbstate.active_mm);
|
|
|
|
if (active_mm == mm)
|
|
leave_mm(smp_processor_id());
|
|
|
|
/* If this cpu still has a stale cr3 reference, then make sure
|
|
it has been flushed. */
|
|
if (percpu_read(xen_current_cr3) == __pa(mm->pgd)) {
|
|
load_cr3(swapper_pg_dir);
|
|
arch_flush_lazy_cpu_mode();
|
|
}
|
|
}
|
|
|
|
static void xen_drop_mm_ref(struct mm_struct *mm)
|
|
{
|
|
cpumask_var_t mask;
|
|
unsigned cpu;
|
|
|
|
if (current->active_mm == mm) {
|
|
if (current->mm == mm)
|
|
load_cr3(swapper_pg_dir);
|
|
else
|
|
leave_mm(smp_processor_id());
|
|
arch_flush_lazy_cpu_mode();
|
|
}
|
|
|
|
/* Get the "official" set of cpus referring to our pagetable. */
|
|
if (!alloc_cpumask_var(&mask, GFP_ATOMIC)) {
|
|
for_each_online_cpu(cpu) {
|
|
if (!cpumask_test_cpu(cpu, &mm->cpu_vm_mask)
|
|
&& per_cpu(xen_current_cr3, cpu) != __pa(mm->pgd))
|
|
continue;
|
|
smp_call_function_single(cpu, drop_other_mm_ref, mm, 1);
|
|
}
|
|
return;
|
|
}
|
|
cpumask_copy(mask, &mm->cpu_vm_mask);
|
|
|
|
/* It's possible that a vcpu may have a stale reference to our
|
|
cr3, because its in lazy mode, and it hasn't yet flushed
|
|
its set of pending hypercalls yet. In this case, we can
|
|
look at its actual current cr3 value, and force it to flush
|
|
if needed. */
|
|
for_each_online_cpu(cpu) {
|
|
if (per_cpu(xen_current_cr3, cpu) == __pa(mm->pgd))
|
|
cpumask_set_cpu(cpu, mask);
|
|
}
|
|
|
|
if (!cpumask_empty(mask))
|
|
smp_call_function_many(mask, drop_other_mm_ref, mm, 1);
|
|
free_cpumask_var(mask);
|
|
}
|
|
#else
|
|
static void xen_drop_mm_ref(struct mm_struct *mm)
|
|
{
|
|
if (current->active_mm == mm)
|
|
load_cr3(swapper_pg_dir);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* While a process runs, Xen pins its pagetables, which means that the
|
|
* hypervisor forces it to be read-only, and it controls all updates
|
|
* to it. This means that all pagetable updates have to go via the
|
|
* hypervisor, which is moderately expensive.
|
|
*
|
|
* Since we're pulling the pagetable down, we switch to use init_mm,
|
|
* unpin old process pagetable and mark it all read-write, which
|
|
* allows further operations on it to be simple memory accesses.
|
|
*
|
|
* The only subtle point is that another CPU may be still using the
|
|
* pagetable because of lazy tlb flushing. This means we need need to
|
|
* switch all CPUs off this pagetable before we can unpin it.
|
|
*/
|
|
void xen_exit_mmap(struct mm_struct *mm)
|
|
{
|
|
get_cpu(); /* make sure we don't move around */
|
|
xen_drop_mm_ref(mm);
|
|
put_cpu();
|
|
|
|
spin_lock(&mm->page_table_lock);
|
|
|
|
/* pgd may not be pinned in the error exit path of execve */
|
|
if (xen_page_pinned(mm->pgd))
|
|
xen_pgd_unpin(mm);
|
|
|
|
spin_unlock(&mm->page_table_lock);
|
|
}
|
|
|
|
static __init void xen_pagetable_setup_start(pgd_t *base)
|
|
{
|
|
}
|
|
|
|
static __init void xen_pagetable_setup_done(pgd_t *base)
|
|
{
|
|
xen_setup_shared_info();
|
|
}
|
|
|
|
static void xen_write_cr2(unsigned long cr2)
|
|
{
|
|
percpu_read(xen_vcpu)->arch.cr2 = cr2;
|
|
}
|
|
|
|
static unsigned long xen_read_cr2(void)
|
|
{
|
|
return percpu_read(xen_vcpu)->arch.cr2;
|
|
}
|
|
|
|
unsigned long xen_read_cr2_direct(void)
|
|
{
|
|
return percpu_read(xen_vcpu_info.arch.cr2);
|
|
}
|
|
|
|
static void xen_flush_tlb(void)
|
|
{
|
|
struct mmuext_op *op;
|
|
struct multicall_space mcs;
|
|
|
|
preempt_disable();
|
|
|
|
mcs = xen_mc_entry(sizeof(*op));
|
|
|
|
op = mcs.args;
|
|
op->cmd = MMUEXT_TLB_FLUSH_LOCAL;
|
|
MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
|
|
|
|
xen_mc_issue(PARAVIRT_LAZY_MMU);
|
|
|
|
preempt_enable();
|
|
}
|
|
|
|
static void xen_flush_tlb_single(unsigned long addr)
|
|
{
|
|
struct mmuext_op *op;
|
|
struct multicall_space mcs;
|
|
|
|
preempt_disable();
|
|
|
|
mcs = xen_mc_entry(sizeof(*op));
|
|
op = mcs.args;
|
|
op->cmd = MMUEXT_INVLPG_LOCAL;
|
|
op->arg1.linear_addr = addr & PAGE_MASK;
|
|
MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
|
|
|
|
xen_mc_issue(PARAVIRT_LAZY_MMU);
|
|
|
|
preempt_enable();
|
|
}
|
|
|
|
static void xen_flush_tlb_others(const struct cpumask *cpus,
|
|
struct mm_struct *mm, unsigned long va)
|
|
{
|
|
struct {
|
|
struct mmuext_op op;
|
|
DECLARE_BITMAP(mask, NR_CPUS);
|
|
} *args;
|
|
struct multicall_space mcs;
|
|
|
|
if (cpumask_empty(cpus))
|
|
return; /* nothing to do */
|
|
|
|
mcs = xen_mc_entry(sizeof(*args));
|
|
args = mcs.args;
|
|
args->op.arg2.vcpumask = to_cpumask(args->mask);
|
|
|
|
/* Remove us, and any offline CPUS. */
|
|
cpumask_and(to_cpumask(args->mask), cpus, cpu_online_mask);
|
|
cpumask_clear_cpu(smp_processor_id(), to_cpumask(args->mask));
|
|
|
|
if (va == TLB_FLUSH_ALL) {
|
|
args->op.cmd = MMUEXT_TLB_FLUSH_MULTI;
|
|
} else {
|
|
args->op.cmd = MMUEXT_INVLPG_MULTI;
|
|
args->op.arg1.linear_addr = va;
|
|
}
|
|
|
|
MULTI_mmuext_op(mcs.mc, &args->op, 1, NULL, DOMID_SELF);
|
|
|
|
xen_mc_issue(PARAVIRT_LAZY_MMU);
|
|
}
|
|
|
|
static unsigned long xen_read_cr3(void)
|
|
{
|
|
return percpu_read(xen_cr3);
|
|
}
|
|
|
|
static void set_current_cr3(void *v)
|
|
{
|
|
percpu_write(xen_current_cr3, (unsigned long)v);
|
|
}
|
|
|
|
static void __xen_write_cr3(bool kernel, unsigned long cr3)
|
|
{
|
|
struct mmuext_op *op;
|
|
struct multicall_space mcs;
|
|
unsigned long mfn;
|
|
|
|
if (cr3)
|
|
mfn = pfn_to_mfn(PFN_DOWN(cr3));
|
|
else
|
|
mfn = 0;
|
|
|
|
WARN_ON(mfn == 0 && kernel);
|
|
|
|
mcs = __xen_mc_entry(sizeof(*op));
|
|
|
|
op = mcs.args;
|
|
op->cmd = kernel ? MMUEXT_NEW_BASEPTR : MMUEXT_NEW_USER_BASEPTR;
|
|
op->arg1.mfn = mfn;
|
|
|
|
MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
|
|
|
|
if (kernel) {
|
|
percpu_write(xen_cr3, cr3);
|
|
|
|
/* Update xen_current_cr3 once the batch has actually
|
|
been submitted. */
|
|
xen_mc_callback(set_current_cr3, (void *)cr3);
|
|
}
|
|
}
|
|
|
|
static void xen_write_cr3(unsigned long cr3)
|
|
{
|
|
BUG_ON(preemptible());
|
|
|
|
xen_mc_batch(); /* disables interrupts */
|
|
|
|
/* Update while interrupts are disabled, so its atomic with
|
|
respect to ipis */
|
|
percpu_write(xen_cr3, cr3);
|
|
|
|
__xen_write_cr3(true, cr3);
|
|
|
|
#ifdef CONFIG_X86_64
|
|
{
|
|
pgd_t *user_pgd = xen_get_user_pgd(__va(cr3));
|
|
if (user_pgd)
|
|
__xen_write_cr3(false, __pa(user_pgd));
|
|
else
|
|
__xen_write_cr3(false, 0);
|
|
}
|
|
#endif
|
|
|
|
xen_mc_issue(PARAVIRT_LAZY_CPU); /* interrupts restored */
|
|
}
|
|
|
|
static int xen_pgd_alloc(struct mm_struct *mm)
|
|
{
|
|
pgd_t *pgd = mm->pgd;
|
|
int ret = 0;
|
|
|
|
BUG_ON(PagePinned(virt_to_page(pgd)));
|
|
|
|
#ifdef CONFIG_X86_64
|
|
{
|
|
struct page *page = virt_to_page(pgd);
|
|
pgd_t *user_pgd;
|
|
|
|
BUG_ON(page->private != 0);
|
|
|
|
ret = -ENOMEM;
|
|
|
|
user_pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
|
|
page->private = (unsigned long)user_pgd;
|
|
|
|
if (user_pgd != NULL) {
|
|
user_pgd[pgd_index(VSYSCALL_START)] =
|
|
__pgd(__pa(level3_user_vsyscall) | _PAGE_TABLE);
|
|
ret = 0;
|
|
}
|
|
|
|
BUG_ON(PagePinned(virt_to_page(xen_get_user_pgd(pgd))));
|
|
}
|
|
#endif
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void xen_pgd_free(struct mm_struct *mm, pgd_t *pgd)
|
|
{
|
|
#ifdef CONFIG_X86_64
|
|
pgd_t *user_pgd = xen_get_user_pgd(pgd);
|
|
|
|
if (user_pgd)
|
|
free_page((unsigned long)user_pgd);
|
|
#endif
|
|
}
|
|
|
|
#ifdef CONFIG_HIGHPTE
|
|
static void *xen_kmap_atomic_pte(struct page *page, enum km_type type)
|
|
{
|
|
pgprot_t prot = PAGE_KERNEL;
|
|
|
|
if (PagePinned(page))
|
|
prot = PAGE_KERNEL_RO;
|
|
|
|
if (0 && PageHighMem(page))
|
|
printk("mapping highpte %lx type %d prot %s\n",
|
|
page_to_pfn(page), type,
|
|
(unsigned long)pgprot_val(prot) & _PAGE_RW ? "WRITE" : "READ");
|
|
|
|
return kmap_atomic_prot(page, type, prot);
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_X86_32
|
|
static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte)
|
|
{
|
|
/* If there's an existing pte, then don't allow _PAGE_RW to be set */
|
|
if (pte_val_ma(*ptep) & _PAGE_PRESENT)
|
|
pte = __pte_ma(((pte_val_ma(*ptep) & _PAGE_RW) | ~_PAGE_RW) &
|
|
pte_val_ma(pte));
|
|
|
|
return pte;
|
|
}
|
|
|
|
/* Init-time set_pte while constructing initial pagetables, which
|
|
doesn't allow RO pagetable pages to be remapped RW */
|
|
static __init void xen_set_pte_init(pte_t *ptep, pte_t pte)
|
|
{
|
|
pte = mask_rw_pte(ptep, pte);
|
|
|
|
xen_set_pte(ptep, pte);
|
|
}
|
|
#endif
|
|
|
|
static void pin_pagetable_pfn(unsigned cmd, unsigned long pfn)
|
|
{
|
|
struct mmuext_op op;
|
|
op.cmd = cmd;
|
|
op.arg1.mfn = pfn_to_mfn(pfn);
|
|
if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF))
|
|
BUG();
|
|
}
|
|
|
|
/* Early in boot, while setting up the initial pagetable, assume
|
|
everything is pinned. */
|
|
static __init void xen_alloc_pte_init(struct mm_struct *mm, unsigned long pfn)
|
|
{
|
|
#ifdef CONFIG_FLATMEM
|
|
BUG_ON(mem_map); /* should only be used early */
|
|
#endif
|
|
make_lowmem_page_readonly(__va(PFN_PHYS(pfn)));
|
|
pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE, pfn);
|
|
}
|
|
|
|
/* Used for pmd and pud */
|
|
static __init void xen_alloc_pmd_init(struct mm_struct *mm, unsigned long pfn)
|
|
{
|
|
#ifdef CONFIG_FLATMEM
|
|
BUG_ON(mem_map); /* should only be used early */
|
|
#endif
|
|
make_lowmem_page_readonly(__va(PFN_PHYS(pfn)));
|
|
}
|
|
|
|
/* Early release_pte assumes that all pts are pinned, since there's
|
|
only init_mm and anything attached to that is pinned. */
|
|
static __init void xen_release_pte_init(unsigned long pfn)
|
|
{
|
|
pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, pfn);
|
|
make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
|
|
}
|
|
|
|
static __init void xen_release_pmd_init(unsigned long pfn)
|
|
{
|
|
make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
|
|
}
|
|
|
|
/* This needs to make sure the new pte page is pinned iff its being
|
|
attached to a pinned pagetable. */
|
|
static void xen_alloc_ptpage(struct mm_struct *mm, unsigned long pfn, unsigned level)
|
|
{
|
|
struct page *page = pfn_to_page(pfn);
|
|
|
|
if (PagePinned(virt_to_page(mm->pgd))) {
|
|
SetPagePinned(page);
|
|
|
|
vm_unmap_aliases();
|
|
if (!PageHighMem(page)) {
|
|
make_lowmem_page_readonly(__va(PFN_PHYS((unsigned long)pfn)));
|
|
if (level == PT_PTE && USE_SPLIT_PTLOCKS)
|
|
pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE, pfn);
|
|
} else {
|
|
/* make sure there are no stray mappings of
|
|
this page */
|
|
kmap_flush_unused();
|
|
}
|
|
}
|
|
}
|
|
|
|
static void xen_alloc_pte(struct mm_struct *mm, unsigned long pfn)
|
|
{
|
|
xen_alloc_ptpage(mm, pfn, PT_PTE);
|
|
}
|
|
|
|
static void xen_alloc_pmd(struct mm_struct *mm, unsigned long pfn)
|
|
{
|
|
xen_alloc_ptpage(mm, pfn, PT_PMD);
|
|
}
|
|
|
|
/* This should never happen until we're OK to use struct page */
|
|
static void xen_release_ptpage(unsigned long pfn, unsigned level)
|
|
{
|
|
struct page *page = pfn_to_page(pfn);
|
|
|
|
if (PagePinned(page)) {
|
|
if (!PageHighMem(page)) {
|
|
if (level == PT_PTE && USE_SPLIT_PTLOCKS)
|
|
pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, pfn);
|
|
make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
|
|
}
|
|
ClearPagePinned(page);
|
|
}
|
|
}
|
|
|
|
static void xen_release_pte(unsigned long pfn)
|
|
{
|
|
xen_release_ptpage(pfn, PT_PTE);
|
|
}
|
|
|
|
static void xen_release_pmd(unsigned long pfn)
|
|
{
|
|
xen_release_ptpage(pfn, PT_PMD);
|
|
}
|
|
|
|
#if PAGETABLE_LEVELS == 4
|
|
static void xen_alloc_pud(struct mm_struct *mm, unsigned long pfn)
|
|
{
|
|
xen_alloc_ptpage(mm, pfn, PT_PUD);
|
|
}
|
|
|
|
static void xen_release_pud(unsigned long pfn)
|
|
{
|
|
xen_release_ptpage(pfn, PT_PUD);
|
|
}
|
|
#endif
|
|
|
|
void __init xen_reserve_top(void)
|
|
{
|
|
#ifdef CONFIG_X86_32
|
|
unsigned long top = HYPERVISOR_VIRT_START;
|
|
struct xen_platform_parameters pp;
|
|
|
|
if (HYPERVISOR_xen_version(XENVER_platform_parameters, &pp) == 0)
|
|
top = pp.virt_start;
|
|
|
|
reserve_top_address(-top);
|
|
#endif /* CONFIG_X86_32 */
|
|
}
|
|
|
|
/*
|
|
* Like __va(), but returns address in the kernel mapping (which is
|
|
* all we have until the physical memory mapping has been set up.
|
|
*/
|
|
static void *__ka(phys_addr_t paddr)
|
|
{
|
|
#ifdef CONFIG_X86_64
|
|
return (void *)(paddr + __START_KERNEL_map);
|
|
#else
|
|
return __va(paddr);
|
|
#endif
|
|
}
|
|
|
|
/* Convert a machine address to physical address */
|
|
static unsigned long m2p(phys_addr_t maddr)
|
|
{
|
|
phys_addr_t paddr;
|
|
|
|
maddr &= PTE_PFN_MASK;
|
|
paddr = mfn_to_pfn(maddr >> PAGE_SHIFT) << PAGE_SHIFT;
|
|
|
|
return paddr;
|
|
}
|
|
|
|
/* Convert a machine address to kernel virtual */
|
|
static void *m2v(phys_addr_t maddr)
|
|
{
|
|
return __ka(m2p(maddr));
|
|
}
|
|
|
|
static void set_page_prot(void *addr, pgprot_t prot)
|
|
{
|
|
unsigned long pfn = __pa(addr) >> PAGE_SHIFT;
|
|
pte_t pte = pfn_pte(pfn, prot);
|
|
|
|
if (HYPERVISOR_update_va_mapping((unsigned long)addr, pte, 0))
|
|
BUG();
|
|
}
|
|
|
|
static __init void xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn)
|
|
{
|
|
unsigned pmdidx, pteidx;
|
|
unsigned ident_pte;
|
|
unsigned long pfn;
|
|
|
|
ident_pte = 0;
|
|
pfn = 0;
|
|
for (pmdidx = 0; pmdidx < PTRS_PER_PMD && pfn < max_pfn; pmdidx++) {
|
|
pte_t *pte_page;
|
|
|
|
/* Reuse or allocate a page of ptes */
|
|
if (pmd_present(pmd[pmdidx]))
|
|
pte_page = m2v(pmd[pmdidx].pmd);
|
|
else {
|
|
/* Check for free pte pages */
|
|
if (ident_pte == ARRAY_SIZE(level1_ident_pgt))
|
|
break;
|
|
|
|
pte_page = &level1_ident_pgt[ident_pte];
|
|
ident_pte += PTRS_PER_PTE;
|
|
|
|
pmd[pmdidx] = __pmd(__pa(pte_page) | _PAGE_TABLE);
|
|
}
|
|
|
|
/* Install mappings */
|
|
for (pteidx = 0; pteidx < PTRS_PER_PTE; pteidx++, pfn++) {
|
|
pte_t pte;
|
|
|
|
if (pfn > max_pfn_mapped)
|
|
max_pfn_mapped = pfn;
|
|
|
|
if (!pte_none(pte_page[pteidx]))
|
|
continue;
|
|
|
|
pte = pfn_pte(pfn, PAGE_KERNEL_EXEC);
|
|
pte_page[pteidx] = pte;
|
|
}
|
|
}
|
|
|
|
for (pteidx = 0; pteidx < ident_pte; pteidx += PTRS_PER_PTE)
|
|
set_page_prot(&level1_ident_pgt[pteidx], PAGE_KERNEL_RO);
|
|
|
|
set_page_prot(pmd, PAGE_KERNEL_RO);
|
|
}
|
|
|
|
#ifdef CONFIG_X86_64
|
|
static void convert_pfn_mfn(void *v)
|
|
{
|
|
pte_t *pte = v;
|
|
int i;
|
|
|
|
/* All levels are converted the same way, so just treat them
|
|
as ptes. */
|
|
for (i = 0; i < PTRS_PER_PTE; i++)
|
|
pte[i] = xen_make_pte(pte[i].pte);
|
|
}
|
|
|
|
/*
|
|
* Set up the inital kernel pagetable.
|
|
*
|
|
* We can construct this by grafting the Xen provided pagetable into
|
|
* head_64.S's preconstructed pagetables. We copy the Xen L2's into
|
|
* level2_ident_pgt, level2_kernel_pgt and level2_fixmap_pgt. This
|
|
* means that only the kernel has a physical mapping to start with -
|
|
* but that's enough to get __va working. We need to fill in the rest
|
|
* of the physical mapping once some sort of allocator has been set
|
|
* up.
|
|
*/
|
|
__init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
|
|
unsigned long max_pfn)
|
|
{
|
|
pud_t *l3;
|
|
pmd_t *l2;
|
|
|
|
/* Zap identity mapping */
|
|
init_level4_pgt[0] = __pgd(0);
|
|
|
|
/* Pre-constructed entries are in pfn, so convert to mfn */
|
|
convert_pfn_mfn(init_level4_pgt);
|
|
convert_pfn_mfn(level3_ident_pgt);
|
|
convert_pfn_mfn(level3_kernel_pgt);
|
|
|
|
l3 = m2v(pgd[pgd_index(__START_KERNEL_map)].pgd);
|
|
l2 = m2v(l3[pud_index(__START_KERNEL_map)].pud);
|
|
|
|
memcpy(level2_ident_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
|
|
memcpy(level2_kernel_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
|
|
|
|
l3 = m2v(pgd[pgd_index(__START_KERNEL_map + PMD_SIZE)].pgd);
|
|
l2 = m2v(l3[pud_index(__START_KERNEL_map + PMD_SIZE)].pud);
|
|
memcpy(level2_fixmap_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
|
|
|
|
/* Set up identity map */
|
|
xen_map_identity_early(level2_ident_pgt, max_pfn);
|
|
|
|
/* Make pagetable pieces RO */
|
|
set_page_prot(init_level4_pgt, PAGE_KERNEL_RO);
|
|
set_page_prot(level3_ident_pgt, PAGE_KERNEL_RO);
|
|
set_page_prot(level3_kernel_pgt, PAGE_KERNEL_RO);
|
|
set_page_prot(level3_user_vsyscall, PAGE_KERNEL_RO);
|
|
set_page_prot(level2_kernel_pgt, PAGE_KERNEL_RO);
|
|
set_page_prot(level2_fixmap_pgt, PAGE_KERNEL_RO);
|
|
|
|
/* Pin down new L4 */
|
|
pin_pagetable_pfn(MMUEXT_PIN_L4_TABLE,
|
|
PFN_DOWN(__pa_symbol(init_level4_pgt)));
|
|
|
|
/* Unpin Xen-provided one */
|
|
pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd)));
|
|
|
|
/* Switch over */
|
|
pgd = init_level4_pgt;
|
|
|
|
/*
|
|
* At this stage there can be no user pgd, and no page
|
|
* structure to attach it to, so make sure we just set kernel
|
|
* pgd.
|
|
*/
|
|
xen_mc_batch();
|
|
__xen_write_cr3(true, __pa(pgd));
|
|
xen_mc_issue(PARAVIRT_LAZY_CPU);
|
|
|
|
reserve_early(__pa(xen_start_info->pt_base),
|
|
__pa(xen_start_info->pt_base +
|
|
xen_start_info->nr_pt_frames * PAGE_SIZE),
|
|
"XEN PAGETABLES");
|
|
|
|
return pgd;
|
|
}
|
|
#else /* !CONFIG_X86_64 */
|
|
static pmd_t level2_kernel_pgt[PTRS_PER_PMD] __page_aligned_bss;
|
|
|
|
__init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
|
|
unsigned long max_pfn)
|
|
{
|
|
pmd_t *kernel_pmd;
|
|
|
|
max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->pt_base) +
|
|
xen_start_info->nr_pt_frames * PAGE_SIZE +
|
|
512*1024);
|
|
|
|
kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd);
|
|
memcpy(level2_kernel_pgt, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD);
|
|
|
|
xen_map_identity_early(level2_kernel_pgt, max_pfn);
|
|
|
|
memcpy(swapper_pg_dir, pgd, sizeof(pgd_t) * PTRS_PER_PGD);
|
|
set_pgd(&swapper_pg_dir[KERNEL_PGD_BOUNDARY],
|
|
__pgd(__pa(level2_kernel_pgt) | _PAGE_PRESENT));
|
|
|
|
set_page_prot(level2_kernel_pgt, PAGE_KERNEL_RO);
|
|
set_page_prot(swapper_pg_dir, PAGE_KERNEL_RO);
|
|
set_page_prot(empty_zero_page, PAGE_KERNEL_RO);
|
|
|
|
pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd)));
|
|
|
|
xen_write_cr3(__pa(swapper_pg_dir));
|
|
|
|
pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, PFN_DOWN(__pa(swapper_pg_dir)));
|
|
|
|
return swapper_pg_dir;
|
|
}
|
|
#endif /* CONFIG_X86_64 */
|
|
|
|
static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot)
|
|
{
|
|
pte_t pte;
|
|
|
|
phys >>= PAGE_SHIFT;
|
|
|
|
switch (idx) {
|
|
case FIX_BTMAP_END ... FIX_BTMAP_BEGIN:
|
|
#ifdef CONFIG_X86_F00F_BUG
|
|
case FIX_F00F_IDT:
|
|
#endif
|
|
#ifdef CONFIG_X86_32
|
|
case FIX_WP_TEST:
|
|
case FIX_VDSO:
|
|
# ifdef CONFIG_HIGHMEM
|
|
case FIX_KMAP_BEGIN ... FIX_KMAP_END:
|
|
# endif
|
|
#else
|
|
case VSYSCALL_LAST_PAGE ... VSYSCALL_FIRST_PAGE:
|
|
#endif
|
|
#ifdef CONFIG_X86_LOCAL_APIC
|
|
case FIX_APIC_BASE: /* maps dummy local APIC */
|
|
#endif
|
|
case FIX_TEXT_POKE0:
|
|
case FIX_TEXT_POKE1:
|
|
/* All local page mappings */
|
|
pte = pfn_pte(phys, prot);
|
|
break;
|
|
|
|
default:
|
|
pte = mfn_pte(phys, prot);
|
|
break;
|
|
}
|
|
|
|
__native_set_fixmap(idx, pte);
|
|
|
|
#ifdef CONFIG_X86_64
|
|
/* Replicate changes to map the vsyscall page into the user
|
|
pagetable vsyscall mapping. */
|
|
if (idx >= VSYSCALL_LAST_PAGE && idx <= VSYSCALL_FIRST_PAGE) {
|
|
unsigned long vaddr = __fix_to_virt(idx);
|
|
set_pte_vaddr_pud(level3_user_vsyscall, vaddr, pte);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
__init void xen_post_allocator_init(void)
|
|
{
|
|
pv_mmu_ops.set_pte = xen_set_pte;
|
|
pv_mmu_ops.set_pmd = xen_set_pmd;
|
|
pv_mmu_ops.set_pud = xen_set_pud;
|
|
#if PAGETABLE_LEVELS == 4
|
|
pv_mmu_ops.set_pgd = xen_set_pgd;
|
|
#endif
|
|
|
|
/* This will work as long as patching hasn't happened yet
|
|
(which it hasn't) */
|
|
pv_mmu_ops.alloc_pte = xen_alloc_pte;
|
|
pv_mmu_ops.alloc_pmd = xen_alloc_pmd;
|
|
pv_mmu_ops.release_pte = xen_release_pte;
|
|
pv_mmu_ops.release_pmd = xen_release_pmd;
|
|
#if PAGETABLE_LEVELS == 4
|
|
pv_mmu_ops.alloc_pud = xen_alloc_pud;
|
|
pv_mmu_ops.release_pud = xen_release_pud;
|
|
#endif
|
|
|
|
#ifdef CONFIG_X86_64
|
|
SetPagePinned(virt_to_page(level3_user_vsyscall));
|
|
#endif
|
|
xen_mark_init_mm_pinned();
|
|
}
|
|
|
|
const struct pv_mmu_ops xen_mmu_ops __initdata = {
|
|
.pagetable_setup_start = xen_pagetable_setup_start,
|
|
.pagetable_setup_done = xen_pagetable_setup_done,
|
|
|
|
.read_cr2 = xen_read_cr2,
|
|
.write_cr2 = xen_write_cr2,
|
|
|
|
.read_cr3 = xen_read_cr3,
|
|
.write_cr3 = xen_write_cr3,
|
|
|
|
.flush_tlb_user = xen_flush_tlb,
|
|
.flush_tlb_kernel = xen_flush_tlb,
|
|
.flush_tlb_single = xen_flush_tlb_single,
|
|
.flush_tlb_others = xen_flush_tlb_others,
|
|
|
|
.pte_update = paravirt_nop,
|
|
.pte_update_defer = paravirt_nop,
|
|
|
|
.pgd_alloc = xen_pgd_alloc,
|
|
.pgd_free = xen_pgd_free,
|
|
|
|
.alloc_pte = xen_alloc_pte_init,
|
|
.release_pte = xen_release_pte_init,
|
|
.alloc_pmd = xen_alloc_pmd_init,
|
|
.alloc_pmd_clone = paravirt_nop,
|
|
.release_pmd = xen_release_pmd_init,
|
|
|
|
#ifdef CONFIG_HIGHPTE
|
|
.kmap_atomic_pte = xen_kmap_atomic_pte,
|
|
#endif
|
|
|
|
#ifdef CONFIG_X86_64
|
|
.set_pte = xen_set_pte,
|
|
#else
|
|
.set_pte = xen_set_pte_init,
|
|
#endif
|
|
.set_pte_at = xen_set_pte_at,
|
|
.set_pmd = xen_set_pmd_hyper,
|
|
|
|
.ptep_modify_prot_start = __ptep_modify_prot_start,
|
|
.ptep_modify_prot_commit = __ptep_modify_prot_commit,
|
|
|
|
.pte_val = PV_CALLEE_SAVE(xen_pte_val),
|
|
.pgd_val = PV_CALLEE_SAVE(xen_pgd_val),
|
|
|
|
.make_pte = PV_CALLEE_SAVE(xen_make_pte),
|
|
.make_pgd = PV_CALLEE_SAVE(xen_make_pgd),
|
|
|
|
#ifdef CONFIG_X86_PAE
|
|
.set_pte_atomic = xen_set_pte_atomic,
|
|
.pte_clear = xen_pte_clear,
|
|
.pmd_clear = xen_pmd_clear,
|
|
#endif /* CONFIG_X86_PAE */
|
|
.set_pud = xen_set_pud_hyper,
|
|
|
|
.make_pmd = PV_CALLEE_SAVE(xen_make_pmd),
|
|
.pmd_val = PV_CALLEE_SAVE(xen_pmd_val),
|
|
|
|
#if PAGETABLE_LEVELS == 4
|
|
.pud_val = PV_CALLEE_SAVE(xen_pud_val),
|
|
.make_pud = PV_CALLEE_SAVE(xen_make_pud),
|
|
.set_pgd = xen_set_pgd_hyper,
|
|
|
|
.alloc_pud = xen_alloc_pmd_init,
|
|
.release_pud = xen_release_pmd_init,
|
|
#endif /* PAGETABLE_LEVELS == 4 */
|
|
|
|
.activate_mm = xen_activate_mm,
|
|
.dup_mmap = xen_dup_mmap,
|
|
.exit_mmap = xen_exit_mmap,
|
|
|
|
.lazy_mode = {
|
|
.enter = paravirt_enter_lazy_mmu,
|
|
.leave = xen_leave_lazy,
|
|
},
|
|
|
|
.set_fixmap = xen_set_fixmap,
|
|
};
|
|
|
|
|
|
#ifdef CONFIG_XEN_DEBUG_FS
|
|
|
|
static struct dentry *d_mmu_debug;
|
|
|
|
static int __init xen_mmu_debugfs(void)
|
|
{
|
|
struct dentry *d_xen = xen_init_debugfs();
|
|
|
|
if (d_xen == NULL)
|
|
return -ENOMEM;
|
|
|
|
d_mmu_debug = debugfs_create_dir("mmu", d_xen);
|
|
|
|
debugfs_create_u8("zero_stats", 0644, d_mmu_debug, &zero_stats);
|
|
|
|
debugfs_create_u32("pgd_update", 0444, d_mmu_debug, &mmu_stats.pgd_update);
|
|
debugfs_create_u32("pgd_update_pinned", 0444, d_mmu_debug,
|
|
&mmu_stats.pgd_update_pinned);
|
|
debugfs_create_u32("pgd_update_batched", 0444, d_mmu_debug,
|
|
&mmu_stats.pgd_update_pinned);
|
|
|
|
debugfs_create_u32("pud_update", 0444, d_mmu_debug, &mmu_stats.pud_update);
|
|
debugfs_create_u32("pud_update_pinned", 0444, d_mmu_debug,
|
|
&mmu_stats.pud_update_pinned);
|
|
debugfs_create_u32("pud_update_batched", 0444, d_mmu_debug,
|
|
&mmu_stats.pud_update_pinned);
|
|
|
|
debugfs_create_u32("pmd_update", 0444, d_mmu_debug, &mmu_stats.pmd_update);
|
|
debugfs_create_u32("pmd_update_pinned", 0444, d_mmu_debug,
|
|
&mmu_stats.pmd_update_pinned);
|
|
debugfs_create_u32("pmd_update_batched", 0444, d_mmu_debug,
|
|
&mmu_stats.pmd_update_pinned);
|
|
|
|
debugfs_create_u32("pte_update", 0444, d_mmu_debug, &mmu_stats.pte_update);
|
|
// debugfs_create_u32("pte_update_pinned", 0444, d_mmu_debug,
|
|
// &mmu_stats.pte_update_pinned);
|
|
debugfs_create_u32("pte_update_batched", 0444, d_mmu_debug,
|
|
&mmu_stats.pte_update_pinned);
|
|
|
|
debugfs_create_u32("mmu_update", 0444, d_mmu_debug, &mmu_stats.mmu_update);
|
|
debugfs_create_u32("mmu_update_extended", 0444, d_mmu_debug,
|
|
&mmu_stats.mmu_update_extended);
|
|
xen_debugfs_create_u32_array("mmu_update_histo", 0444, d_mmu_debug,
|
|
mmu_stats.mmu_update_histo, 20);
|
|
|
|
debugfs_create_u32("set_pte_at", 0444, d_mmu_debug, &mmu_stats.set_pte_at);
|
|
debugfs_create_u32("set_pte_at_batched", 0444, d_mmu_debug,
|
|
&mmu_stats.set_pte_at_batched);
|
|
debugfs_create_u32("set_pte_at_current", 0444, d_mmu_debug,
|
|
&mmu_stats.set_pte_at_current);
|
|
debugfs_create_u32("set_pte_at_kernel", 0444, d_mmu_debug,
|
|
&mmu_stats.set_pte_at_kernel);
|
|
|
|
debugfs_create_u32("prot_commit", 0444, d_mmu_debug, &mmu_stats.prot_commit);
|
|
debugfs_create_u32("prot_commit_batched", 0444, d_mmu_debug,
|
|
&mmu_stats.prot_commit_batched);
|
|
|
|
return 0;
|
|
}
|
|
fs_initcall(xen_mmu_debugfs);
|
|
|
|
#endif /* CONFIG_XEN_DEBUG_FS */
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