4 * This file contains the various mmu fetch and update operations.
5 * The most important job they must perform is the mapping between the
6 * domain's pfn and the overall machine mfns.
8 * Xen allows guests to directly update the pagetable, in a controlled
9 * fashion. In other words, the guest modifies the same pagetable
10 * that the CPU actually uses, which eliminates the overhead of having
11 * a separate shadow pagetable.
13 * In order to allow this, it falls on the guest domain to map its
14 * notion of a "physical" pfn - which is just a domain-local linear
15 * address - into a real "machine address" which the CPU's MMU can
18 * A pgd_t/pmd_t/pte_t will typically contain an mfn, and so can be
19 * inserted directly into the pagetable. When creating a new
20 * pte/pmd/pgd, it converts the passed pfn into an mfn. Conversely,
21 * when reading the content back with __(pgd|pmd|pte)_val, it converts
22 * the mfn back into a pfn.
24 * The other constraint is that all pages which make up a pagetable
25 * must be mapped read-only in the guest. This prevents uncontrolled
26 * guest updates to the pagetable. Xen strictly enforces this, and
27 * will disallow any pagetable update which will end up mapping a
28 * pagetable page RW, and will disallow using any writable page as a
31 * Naively, when loading %cr3 with the base of a new pagetable, Xen
32 * would need to validate the whole pagetable before going on.
33 * Naturally, this is quite slow. The solution is to "pin" a
34 * pagetable, which enforces all the constraints on the pagetable even
35 * when it is not actively in use. This menas that Xen can be assured
36 * that it is still valid when you do load it into %cr3, and doesn't
37 * need to revalidate it.
39 * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
41 #include <linux/sched.h>
42 #include <linux/highmem.h>
43 #include <linux/debugfs.h>
44 #include <linux/bug.h>
45 #include <linux/vmalloc.h>
46 #include <linux/module.h>
47 #include <linux/gfp.h>
48 #include <linux/memblock.h>
50 #include <asm/pgtable.h>
51 #include <asm/tlbflush.h>
52 #include <asm/fixmap.h>
53 #include <asm/mmu_context.h>
54 #include <asm/setup.h>
55 #include <asm/paravirt.h>
57 #include <asm/linkage.h>
62 #include <asm/xen/hypercall.h>
63 #include <asm/xen/hypervisor.h>
67 #include <xen/interface/xen.h>
68 #include <xen/interface/hvm/hvm_op.h>
69 #include <xen/interface/version.h>
70 #include <xen/interface/memory.h>
71 #include <xen/hvc-console.h>
73 #include "multicalls.h"
77 #define MMU_UPDATE_HISTO 30
80 * Protects atomic reservation decrease/increase against concurrent increases.
81 * Also protects non-atomic updates of current_pages and driver_pages, and
84 DEFINE_SPINLOCK(xen_reservation_lock);
86 #ifdef CONFIG_XEN_DEBUG_FS
90 u32 pgd_update_pinned;
91 u32 pgd_update_batched;
94 u32 pud_update_pinned;
95 u32 pud_update_batched;
98 u32 pmd_update_pinned;
99 u32 pmd_update_batched;
102 u32 pte_update_pinned;
103 u32 pte_update_batched;
106 u32 mmu_update_extended;
107 u32 mmu_update_histo[MMU_UPDATE_HISTO];
110 u32 prot_commit_batched;
113 u32 set_pte_at_batched;
114 u32 set_pte_at_pinned;
115 u32 set_pte_at_current;
116 u32 set_pte_at_kernel;
119 static u8 zero_stats;
121 static inline void check_zero(void)
123 if (unlikely(zero_stats)) {
124 memset(&mmu_stats, 0, sizeof(mmu_stats));
129 #define ADD_STATS(elem, val) \
130 do { check_zero(); mmu_stats.elem += (val); } while(0)
132 #else /* !CONFIG_XEN_DEBUG_FS */
134 #define ADD_STATS(elem, val) do { (void)(val); } while(0)
136 #endif /* CONFIG_XEN_DEBUG_FS */
140 * Identity map, in addition to plain kernel map. This needs to be
141 * large enough to allocate page table pages to allocate the rest.
142 * Each page can map 2MB.
144 #define LEVEL1_IDENT_ENTRIES (PTRS_PER_PTE * 4)
145 static RESERVE_BRK_ARRAY(pte_t, level1_ident_pgt, LEVEL1_IDENT_ENTRIES);
148 /* l3 pud for userspace vsyscall mapping */
149 static pud_t level3_user_vsyscall[PTRS_PER_PUD] __page_aligned_bss;
150 #endif /* CONFIG_X86_64 */
153 * Note about cr3 (pagetable base) values:
155 * xen_cr3 contains the current logical cr3 value; it contains the
156 * last set cr3. This may not be the current effective cr3, because
157 * its update may be being lazily deferred. However, a vcpu looking
158 * at its own cr3 can use this value knowing that it everything will
159 * be self-consistent.
161 * xen_current_cr3 contains the actual vcpu cr3; it is set once the
162 * hypercall to set the vcpu cr3 is complete (so it may be a little
163 * out of date, but it will never be set early). If one vcpu is
164 * looking at another vcpu's cr3 value, it should use this variable.
166 DEFINE_PER_CPU(unsigned long, xen_cr3); /* cr3 stored as physaddr */
167 DEFINE_PER_CPU(unsigned long, xen_current_cr3); /* actual vcpu cr3 */
171 * Just beyond the highest usermode address. STACK_TOP_MAX has a
172 * redzone above it, so round it up to a PGD boundary.
174 #define USER_LIMIT ((STACK_TOP_MAX + PGDIR_SIZE - 1) & PGDIR_MASK)
176 unsigned long arbitrary_virt_to_mfn(void *vaddr)
178 xmaddr_t maddr = arbitrary_virt_to_machine(vaddr);
180 return PFN_DOWN(maddr.maddr);
183 xmaddr_t arbitrary_virt_to_machine(void *vaddr)
185 unsigned long address = (unsigned long)vaddr;
191 * if the PFN is in the linear mapped vaddr range, we can just use
192 * the (quick) virt_to_machine() p2m lookup
194 if (virt_addr_valid(vaddr))
195 return virt_to_machine(vaddr);
197 /* otherwise we have to do a (slower) full page-table walk */
199 pte = lookup_address(address, &level);
201 offset = address & ~PAGE_MASK;
202 return XMADDR(((phys_addr_t)pte_mfn(*pte) << PAGE_SHIFT) + offset);
204 EXPORT_SYMBOL_GPL(arbitrary_virt_to_machine);
206 void make_lowmem_page_readonly(void *vaddr)
209 unsigned long address = (unsigned long)vaddr;
212 pte = lookup_address(address, &level);
214 return; /* vaddr missing */
216 ptev = pte_wrprotect(*pte);
218 if (HYPERVISOR_update_va_mapping(address, ptev, 0))
222 void make_lowmem_page_readwrite(void *vaddr)
225 unsigned long address = (unsigned long)vaddr;
228 pte = lookup_address(address, &level);
230 return; /* vaddr missing */
232 ptev = pte_mkwrite(*pte);
234 if (HYPERVISOR_update_va_mapping(address, ptev, 0))
239 static bool xen_page_pinned(void *ptr)
241 struct page *page = virt_to_page(ptr);
243 return PagePinned(page);
246 static bool xen_iomap_pte(pte_t pte)
248 return pte_flags(pte) & _PAGE_IOMAP;
251 void xen_set_domain_pte(pte_t *ptep, pte_t pteval, unsigned domid)
253 struct multicall_space mcs;
254 struct mmu_update *u;
256 mcs = xen_mc_entry(sizeof(*u));
259 /* ptep might be kmapped when using 32-bit HIGHPTE */
260 u->ptr = arbitrary_virt_to_machine(ptep).maddr;
261 u->val = pte_val_ma(pteval);
263 MULTI_mmu_update(mcs.mc, mcs.args, 1, NULL, domid);
265 xen_mc_issue(PARAVIRT_LAZY_MMU);
267 EXPORT_SYMBOL_GPL(xen_set_domain_pte);
269 static void xen_set_iomap_pte(pte_t *ptep, pte_t pteval)
271 xen_set_domain_pte(ptep, pteval, DOMID_IO);
274 static void xen_extend_mmu_update(const struct mmu_update *update)
276 struct multicall_space mcs;
277 struct mmu_update *u;
279 mcs = xen_mc_extend_args(__HYPERVISOR_mmu_update, sizeof(*u));
281 if (mcs.mc != NULL) {
282 ADD_STATS(mmu_update_extended, 1);
283 ADD_STATS(mmu_update_histo[mcs.mc->args[1]], -1);
287 if (mcs.mc->args[1] < MMU_UPDATE_HISTO)
288 ADD_STATS(mmu_update_histo[mcs.mc->args[1]], 1);
290 ADD_STATS(mmu_update_histo[0], 1);
292 ADD_STATS(mmu_update, 1);
293 mcs = __xen_mc_entry(sizeof(*u));
294 MULTI_mmu_update(mcs.mc, mcs.args, 1, NULL, DOMID_SELF);
295 ADD_STATS(mmu_update_histo[1], 1);
302 void xen_set_pmd_hyper(pmd_t *ptr, pmd_t val)
310 /* ptr may be ioremapped for 64-bit pagetable setup */
311 u.ptr = arbitrary_virt_to_machine(ptr).maddr;
312 u.val = pmd_val_ma(val);
313 xen_extend_mmu_update(&u);
315 ADD_STATS(pmd_update_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU);
317 xen_mc_issue(PARAVIRT_LAZY_MMU);
322 void xen_set_pmd(pmd_t *ptr, pmd_t val)
324 ADD_STATS(pmd_update, 1);
326 /* If page is not pinned, we can just update the entry
328 if (!xen_page_pinned(ptr)) {
333 ADD_STATS(pmd_update_pinned, 1);
335 xen_set_pmd_hyper(ptr, val);
339 * Associate a virtual page frame with a given physical page frame
340 * and protection flags for that frame.
342 void set_pte_mfn(unsigned long vaddr, unsigned long mfn, pgprot_t flags)
344 set_pte_vaddr(vaddr, mfn_pte(mfn, flags));
347 void xen_set_pte_at(struct mm_struct *mm, unsigned long addr,
348 pte_t *ptep, pte_t pteval)
350 if (xen_iomap_pte(pteval)) {
351 xen_set_iomap_pte(ptep, pteval);
355 ADD_STATS(set_pte_at, 1);
356 // ADD_STATS(set_pte_at_pinned, xen_page_pinned(ptep));
357 ADD_STATS(set_pte_at_current, mm == current->mm);
358 ADD_STATS(set_pte_at_kernel, mm == &init_mm);
360 if (mm == current->mm || mm == &init_mm) {
361 if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) {
362 struct multicall_space mcs;
363 mcs = xen_mc_entry(0);
365 MULTI_update_va_mapping(mcs.mc, addr, pteval, 0);
366 ADD_STATS(set_pte_at_batched, 1);
367 xen_mc_issue(PARAVIRT_LAZY_MMU);
370 if (HYPERVISOR_update_va_mapping(addr, pteval, 0) == 0)
373 xen_set_pte(ptep, pteval);
378 pte_t xen_ptep_modify_prot_start(struct mm_struct *mm,
379 unsigned long addr, pte_t *ptep)
381 /* Just return the pte as-is. We preserve the bits on commit */
385 void xen_ptep_modify_prot_commit(struct mm_struct *mm, unsigned long addr,
386 pte_t *ptep, pte_t pte)
392 u.ptr = arbitrary_virt_to_machine(ptep).maddr | MMU_PT_UPDATE_PRESERVE_AD;
393 u.val = pte_val_ma(pte);
394 xen_extend_mmu_update(&u);
396 ADD_STATS(prot_commit, 1);
397 ADD_STATS(prot_commit_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU);
399 xen_mc_issue(PARAVIRT_LAZY_MMU);
402 /* Assume pteval_t is equivalent to all the other *val_t types. */
403 static pteval_t pte_mfn_to_pfn(pteval_t val)
405 if (val & _PAGE_PRESENT) {
406 unsigned long mfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT;
407 pteval_t flags = val & PTE_FLAGS_MASK;
408 val = ((pteval_t)mfn_to_pfn(mfn) << PAGE_SHIFT) | flags;
414 static pteval_t pte_pfn_to_mfn(pteval_t val)
416 if (val & _PAGE_PRESENT) {
417 unsigned long pfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT;
418 pteval_t flags = val & PTE_FLAGS_MASK;
419 unsigned long mfn = pfn_to_mfn(pfn);
422 * If there's no mfn for the pfn, then just create an
423 * empty non-present pte. Unfortunately this loses
424 * information about the original pfn, so
425 * pte_mfn_to_pfn is asymmetric.
427 if (unlikely(mfn == INVALID_P2M_ENTRY)) {
432 val = ((pteval_t)mfn << PAGE_SHIFT) | flags;
438 static pteval_t iomap_pte(pteval_t val)
440 if (val & _PAGE_PRESENT) {
441 unsigned long pfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT;
442 pteval_t flags = val & PTE_FLAGS_MASK;
444 /* We assume the pte frame number is a MFN, so
445 just use it as-is. */
446 val = ((pteval_t)pfn << PAGE_SHIFT) | flags;
452 pteval_t xen_pte_val(pte_t pte)
454 pteval_t pteval = pte.pte;
456 /* If this is a WC pte, convert back from Xen WC to Linux WC */
457 if ((pteval & (_PAGE_PAT | _PAGE_PCD | _PAGE_PWT)) == _PAGE_PAT) {
458 WARN_ON(!pat_enabled);
459 pteval = (pteval & ~_PAGE_PAT) | _PAGE_PWT;
462 if (xen_initial_domain() && (pteval & _PAGE_IOMAP))
465 return pte_mfn_to_pfn(pteval);
467 PV_CALLEE_SAVE_REGS_THUNK(xen_pte_val);
469 pgdval_t xen_pgd_val(pgd_t pgd)
471 return pte_mfn_to_pfn(pgd.pgd);
473 PV_CALLEE_SAVE_REGS_THUNK(xen_pgd_val);
476 * Xen's PAT setup is part of its ABI, though I assume entries 6 & 7
477 * are reserved for now, to correspond to the Intel-reserved PAT
480 * We expect Linux's PAT set as follows:
482 * Idx PTE flags Linux Xen Default
489 * 6 PAT PCD UC- UC UC-
490 * 7 PAT PCD PWT UC UC UC
493 void xen_set_pat(u64 pat)
495 /* We expect Linux to use a PAT setting of
496 * UC UC- WC WB (ignoring the PAT flag) */
497 WARN_ON(pat != 0x0007010600070106ull);
500 pte_t xen_make_pte(pteval_t pte)
502 phys_addr_t addr = (pte & PTE_PFN_MASK);
504 /* If Linux is trying to set a WC pte, then map to the Xen WC.
505 * If _PAGE_PAT is set, then it probably means it is really
506 * _PAGE_PSE, so avoid fiddling with the PAT mapping and hope
507 * things work out OK...
509 * (We should never see kernel mappings with _PAGE_PSE set,
510 * but we could see hugetlbfs mappings, I think.).
512 if (pat_enabled && !WARN_ON(pte & _PAGE_PAT)) {
513 if ((pte & (_PAGE_PCD | _PAGE_PWT)) == _PAGE_PWT)
514 pte = (pte & ~(_PAGE_PCD | _PAGE_PWT)) | _PAGE_PAT;
518 * Unprivileged domains are allowed to do IOMAPpings for
519 * PCI passthrough, but not map ISA space. The ISA
520 * mappings are just dummy local mappings to keep other
521 * parts of the kernel happy.
523 if (unlikely(pte & _PAGE_IOMAP) &&
524 (xen_initial_domain() || addr >= ISA_END_ADDRESS)) {
525 pte = iomap_pte(pte);
528 pte = pte_pfn_to_mfn(pte);
531 return native_make_pte(pte);
533 PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte);
535 pgd_t xen_make_pgd(pgdval_t pgd)
537 pgd = pte_pfn_to_mfn(pgd);
538 return native_make_pgd(pgd);
540 PV_CALLEE_SAVE_REGS_THUNK(xen_make_pgd);
542 pmdval_t xen_pmd_val(pmd_t pmd)
544 return pte_mfn_to_pfn(pmd.pmd);
546 PV_CALLEE_SAVE_REGS_THUNK(xen_pmd_val);
548 void xen_set_pud_hyper(pud_t *ptr, pud_t val)
556 /* ptr may be ioremapped for 64-bit pagetable setup */
557 u.ptr = arbitrary_virt_to_machine(ptr).maddr;
558 u.val = pud_val_ma(val);
559 xen_extend_mmu_update(&u);
561 ADD_STATS(pud_update_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU);
563 xen_mc_issue(PARAVIRT_LAZY_MMU);
568 void xen_set_pud(pud_t *ptr, pud_t val)
570 ADD_STATS(pud_update, 1);
572 /* If page is not pinned, we can just update the entry
574 if (!xen_page_pinned(ptr)) {
579 ADD_STATS(pud_update_pinned, 1);
581 xen_set_pud_hyper(ptr, val);
584 void xen_set_pte(pte_t *ptep, pte_t pte)
586 if (xen_iomap_pte(pte)) {
587 xen_set_iomap_pte(ptep, pte);
591 ADD_STATS(pte_update, 1);
592 // ADD_STATS(pte_update_pinned, xen_page_pinned(ptep));
593 ADD_STATS(pte_update_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU);
595 #ifdef CONFIG_X86_PAE
596 ptep->pte_high = pte.pte_high;
598 ptep->pte_low = pte.pte_low;
604 #ifdef CONFIG_X86_PAE
605 void xen_set_pte_atomic(pte_t *ptep, pte_t pte)
607 if (xen_iomap_pte(pte)) {
608 xen_set_iomap_pte(ptep, pte);
612 set_64bit((u64 *)ptep, native_pte_val(pte));
615 void xen_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
618 smp_wmb(); /* make sure low gets written first */
622 void xen_pmd_clear(pmd_t *pmdp)
624 set_pmd(pmdp, __pmd(0));
626 #endif /* CONFIG_X86_PAE */
628 pmd_t xen_make_pmd(pmdval_t pmd)
630 pmd = pte_pfn_to_mfn(pmd);
631 return native_make_pmd(pmd);
633 PV_CALLEE_SAVE_REGS_THUNK(xen_make_pmd);
635 #if PAGETABLE_LEVELS == 4
636 pudval_t xen_pud_val(pud_t pud)
638 return pte_mfn_to_pfn(pud.pud);
640 PV_CALLEE_SAVE_REGS_THUNK(xen_pud_val);
642 pud_t xen_make_pud(pudval_t pud)
644 pud = pte_pfn_to_mfn(pud);
646 return native_make_pud(pud);
648 PV_CALLEE_SAVE_REGS_THUNK(xen_make_pud);
650 pgd_t *xen_get_user_pgd(pgd_t *pgd)
652 pgd_t *pgd_page = (pgd_t *)(((unsigned long)pgd) & PAGE_MASK);
653 unsigned offset = pgd - pgd_page;
654 pgd_t *user_ptr = NULL;
656 if (offset < pgd_index(USER_LIMIT)) {
657 struct page *page = virt_to_page(pgd_page);
658 user_ptr = (pgd_t *)page->private;
666 static void __xen_set_pgd_hyper(pgd_t *ptr, pgd_t val)
670 u.ptr = virt_to_machine(ptr).maddr;
671 u.val = pgd_val_ma(val);
672 xen_extend_mmu_update(&u);
676 * Raw hypercall-based set_pgd, intended for in early boot before
677 * there's a page structure. This implies:
678 * 1. The only existing pagetable is the kernel's
679 * 2. It is always pinned
680 * 3. It has no user pagetable attached to it
682 void __init xen_set_pgd_hyper(pgd_t *ptr, pgd_t val)
688 __xen_set_pgd_hyper(ptr, val);
690 xen_mc_issue(PARAVIRT_LAZY_MMU);
695 void xen_set_pgd(pgd_t *ptr, pgd_t val)
697 pgd_t *user_ptr = xen_get_user_pgd(ptr);
699 ADD_STATS(pgd_update, 1);
701 /* If page is not pinned, we can just update the entry
703 if (!xen_page_pinned(ptr)) {
706 WARN_ON(xen_page_pinned(user_ptr));
712 ADD_STATS(pgd_update_pinned, 1);
713 ADD_STATS(pgd_update_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU);
715 /* If it's pinned, then we can at least batch the kernel and
716 user updates together. */
719 __xen_set_pgd_hyper(ptr, val);
721 __xen_set_pgd_hyper(user_ptr, val);
723 xen_mc_issue(PARAVIRT_LAZY_MMU);
725 #endif /* PAGETABLE_LEVELS == 4 */
728 * (Yet another) pagetable walker. This one is intended for pinning a
729 * pagetable. This means that it walks a pagetable and calls the
730 * callback function on each page it finds making up the page table,
731 * at every level. It walks the entire pagetable, but it only bothers
732 * pinning pte pages which are below limit. In the normal case this
733 * will be STACK_TOP_MAX, but at boot we need to pin up to
736 * For 32-bit the important bit is that we don't pin beyond there,
737 * because then we start getting into Xen's ptes.
739 * For 64-bit, we must skip the Xen hole in the middle of the address
740 * space, just after the big x86-64 virtual hole.
742 static int __xen_pgd_walk(struct mm_struct *mm, pgd_t *pgd,
743 int (*func)(struct mm_struct *mm, struct page *,
748 unsigned hole_low, hole_high;
749 unsigned pgdidx_limit, pudidx_limit, pmdidx_limit;
750 unsigned pgdidx, pudidx, pmdidx;
752 /* The limit is the last byte to be touched */
754 BUG_ON(limit >= FIXADDR_TOP);
756 if (xen_feature(XENFEAT_auto_translated_physmap))
760 * 64-bit has a great big hole in the middle of the address
761 * space, which contains the Xen mappings. On 32-bit these
762 * will end up making a zero-sized hole and so is a no-op.
764 hole_low = pgd_index(USER_LIMIT);
765 hole_high = pgd_index(PAGE_OFFSET);
767 pgdidx_limit = pgd_index(limit);
769 pudidx_limit = pud_index(limit);
774 pmdidx_limit = pmd_index(limit);
779 for (pgdidx = 0; pgdidx <= pgdidx_limit; pgdidx++) {
782 if (pgdidx >= hole_low && pgdidx < hole_high)
785 if (!pgd_val(pgd[pgdidx]))
788 pud = pud_offset(&pgd[pgdidx], 0);
790 if (PTRS_PER_PUD > 1) /* not folded */
791 flush |= (*func)(mm, virt_to_page(pud), PT_PUD);
793 for (pudidx = 0; pudidx < PTRS_PER_PUD; pudidx++) {
796 if (pgdidx == pgdidx_limit &&
797 pudidx > pudidx_limit)
800 if (pud_none(pud[pudidx]))
803 pmd = pmd_offset(&pud[pudidx], 0);
805 if (PTRS_PER_PMD > 1) /* not folded */
806 flush |= (*func)(mm, virt_to_page(pmd), PT_PMD);
808 for (pmdidx = 0; pmdidx < PTRS_PER_PMD; pmdidx++) {
811 if (pgdidx == pgdidx_limit &&
812 pudidx == pudidx_limit &&
813 pmdidx > pmdidx_limit)
816 if (pmd_none(pmd[pmdidx]))
819 pte = pmd_page(pmd[pmdidx]);
820 flush |= (*func)(mm, pte, PT_PTE);
826 /* Do the top level last, so that the callbacks can use it as
827 a cue to do final things like tlb flushes. */
828 flush |= (*func)(mm, virt_to_page(pgd), PT_PGD);
833 static int xen_pgd_walk(struct mm_struct *mm,
834 int (*func)(struct mm_struct *mm, struct page *,
838 return __xen_pgd_walk(mm, mm->pgd, func, limit);
841 /* If we're using split pte locks, then take the page's lock and
842 return a pointer to it. Otherwise return NULL. */
843 static spinlock_t *xen_pte_lock(struct page *page, struct mm_struct *mm)
845 spinlock_t *ptl = NULL;
847 #if USE_SPLIT_PTLOCKS
848 ptl = __pte_lockptr(page);
849 spin_lock_nest_lock(ptl, &mm->page_table_lock);
855 static void xen_pte_unlock(void *v)
861 static void xen_do_pin(unsigned level, unsigned long pfn)
863 struct mmuext_op *op;
864 struct multicall_space mcs;
866 mcs = __xen_mc_entry(sizeof(*op));
869 op->arg1.mfn = pfn_to_mfn(pfn);
870 MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
873 static int xen_pin_page(struct mm_struct *mm, struct page *page,
876 unsigned pgfl = TestSetPagePinned(page);
880 flush = 0; /* already pinned */
881 else if (PageHighMem(page))
882 /* kmaps need flushing if we found an unpinned
886 void *pt = lowmem_page_address(page);
887 unsigned long pfn = page_to_pfn(page);
888 struct multicall_space mcs = __xen_mc_entry(0);
894 * We need to hold the pagetable lock between the time
895 * we make the pagetable RO and when we actually pin
896 * it. If we don't, then other users may come in and
897 * attempt to update the pagetable by writing it,
898 * which will fail because the memory is RO but not
899 * pinned, so Xen won't do the trap'n'emulate.
901 * If we're using split pte locks, we can't hold the
902 * entire pagetable's worth of locks during the
903 * traverse, because we may wrap the preempt count (8
904 * bits). The solution is to mark RO and pin each PTE
905 * page while holding the lock. This means the number
906 * of locks we end up holding is never more than a
907 * batch size (~32 entries, at present).
909 * If we're not using split pte locks, we needn't pin
910 * the PTE pages independently, because we're
911 * protected by the overall pagetable lock.
915 ptl = xen_pte_lock(page, mm);
917 MULTI_update_va_mapping(mcs.mc, (unsigned long)pt,
918 pfn_pte(pfn, PAGE_KERNEL_RO),
919 level == PT_PGD ? UVMF_TLB_FLUSH : 0);
922 xen_do_pin(MMUEXT_PIN_L1_TABLE, pfn);
924 /* Queue a deferred unlock for when this batch
926 xen_mc_callback(xen_pte_unlock, ptl);
933 /* This is called just after a mm has been created, but it has not
934 been used yet. We need to make sure that its pagetable is all
935 read-only, and can be pinned. */
936 static void __xen_pgd_pin(struct mm_struct *mm, pgd_t *pgd)
940 if (__xen_pgd_walk(mm, pgd, xen_pin_page, USER_LIMIT)) {
941 /* re-enable interrupts for flushing */
951 pgd_t *user_pgd = xen_get_user_pgd(pgd);
953 xen_do_pin(MMUEXT_PIN_L4_TABLE, PFN_DOWN(__pa(pgd)));
956 xen_pin_page(mm, virt_to_page(user_pgd), PT_PGD);
957 xen_do_pin(MMUEXT_PIN_L4_TABLE,
958 PFN_DOWN(__pa(user_pgd)));
961 #else /* CONFIG_X86_32 */
962 #ifdef CONFIG_X86_PAE
963 /* Need to make sure unshared kernel PMD is pinnable */
964 xen_pin_page(mm, pgd_page(pgd[pgd_index(TASK_SIZE)]),
967 xen_do_pin(MMUEXT_PIN_L3_TABLE, PFN_DOWN(__pa(pgd)));
968 #endif /* CONFIG_X86_64 */
972 static void xen_pgd_pin(struct mm_struct *mm)
974 __xen_pgd_pin(mm, mm->pgd);
978 * On save, we need to pin all pagetables to make sure they get their
979 * mfns turned into pfns. Search the list for any unpinned pgds and pin
980 * them (unpinned pgds are not currently in use, probably because the
981 * process is under construction or destruction).
983 * Expected to be called in stop_machine() ("equivalent to taking
984 * every spinlock in the system"), so the locking doesn't really
985 * matter all that much.
987 void xen_mm_pin_all(void)
991 spin_lock(&pgd_lock);
993 list_for_each_entry(page, &pgd_list, lru) {
994 if (!PagePinned(page)) {
995 __xen_pgd_pin(&init_mm, (pgd_t *)page_address(page));
996 SetPageSavePinned(page);
1000 spin_unlock(&pgd_lock);
1004 * The init_mm pagetable is really pinned as soon as its created, but
1005 * that's before we have page structures to store the bits. So do all
1006 * the book-keeping now.
1008 static __init int xen_mark_pinned(struct mm_struct *mm, struct page *page,
1009 enum pt_level level)
1011 SetPagePinned(page);
1015 static void __init xen_mark_init_mm_pinned(void)
1017 xen_pgd_walk(&init_mm, xen_mark_pinned, FIXADDR_TOP);
1020 static int xen_unpin_page(struct mm_struct *mm, struct page *page,
1021 enum pt_level level)
1023 unsigned pgfl = TestClearPagePinned(page);
1025 if (pgfl && !PageHighMem(page)) {
1026 void *pt = lowmem_page_address(page);
1027 unsigned long pfn = page_to_pfn(page);
1028 spinlock_t *ptl = NULL;
1029 struct multicall_space mcs;
1032 * Do the converse to pin_page. If we're using split
1033 * pte locks, we must be holding the lock for while
1034 * the pte page is unpinned but still RO to prevent
1035 * concurrent updates from seeing it in this
1036 * partially-pinned state.
1038 if (level == PT_PTE) {
1039 ptl = xen_pte_lock(page, mm);
1042 xen_do_pin(MMUEXT_UNPIN_TABLE, pfn);
1045 mcs = __xen_mc_entry(0);
1047 MULTI_update_va_mapping(mcs.mc, (unsigned long)pt,
1048 pfn_pte(pfn, PAGE_KERNEL),
1049 level == PT_PGD ? UVMF_TLB_FLUSH : 0);
1052 /* unlock when batch completed */
1053 xen_mc_callback(xen_pte_unlock, ptl);
1057 return 0; /* never need to flush on unpin */
1060 /* Release a pagetables pages back as normal RW */
1061 static void __xen_pgd_unpin(struct mm_struct *mm, pgd_t *pgd)
1065 xen_do_pin(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd)));
1067 #ifdef CONFIG_X86_64
1069 pgd_t *user_pgd = xen_get_user_pgd(pgd);
1072 xen_do_pin(MMUEXT_UNPIN_TABLE,
1073 PFN_DOWN(__pa(user_pgd)));
1074 xen_unpin_page(mm, virt_to_page(user_pgd), PT_PGD);
1079 #ifdef CONFIG_X86_PAE
1080 /* Need to make sure unshared kernel PMD is unpinned */
1081 xen_unpin_page(mm, pgd_page(pgd[pgd_index(TASK_SIZE)]),
1085 __xen_pgd_walk(mm, pgd, xen_unpin_page, USER_LIMIT);
1090 static void xen_pgd_unpin(struct mm_struct *mm)
1092 __xen_pgd_unpin(mm, mm->pgd);
1096 * On resume, undo any pinning done at save, so that the rest of the
1097 * kernel doesn't see any unexpected pinned pagetables.
1099 void xen_mm_unpin_all(void)
1103 spin_lock(&pgd_lock);
1105 list_for_each_entry(page, &pgd_list, lru) {
1106 if (PageSavePinned(page)) {
1107 BUG_ON(!PagePinned(page));
1108 __xen_pgd_unpin(&init_mm, (pgd_t *)page_address(page));
1109 ClearPageSavePinned(page);
1113 spin_unlock(&pgd_lock);
1116 void xen_activate_mm(struct mm_struct *prev, struct mm_struct *next)
1118 spin_lock(&next->page_table_lock);
1120 spin_unlock(&next->page_table_lock);
1123 void xen_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
1125 spin_lock(&mm->page_table_lock);
1127 spin_unlock(&mm->page_table_lock);
1132 /* Another cpu may still have their %cr3 pointing at the pagetable, so
1133 we need to repoint it somewhere else before we can unpin it. */
1134 static void drop_other_mm_ref(void *info)
1136 struct mm_struct *mm = info;
1137 struct mm_struct *active_mm;
1139 active_mm = percpu_read(cpu_tlbstate.active_mm);
1141 if (active_mm == mm && percpu_read(cpu_tlbstate.state) != TLBSTATE_OK)
1142 leave_mm(smp_processor_id());
1144 /* If this cpu still has a stale cr3 reference, then make sure
1145 it has been flushed. */
1146 if (percpu_read(xen_current_cr3) == __pa(mm->pgd))
1147 load_cr3(swapper_pg_dir);
1150 static void xen_drop_mm_ref(struct mm_struct *mm)
1155 if (current->active_mm == mm) {
1156 if (current->mm == mm)
1157 load_cr3(swapper_pg_dir);
1159 leave_mm(smp_processor_id());
1162 /* Get the "official" set of cpus referring to our pagetable. */
1163 if (!alloc_cpumask_var(&mask, GFP_ATOMIC)) {
1164 for_each_online_cpu(cpu) {
1165 if (!cpumask_test_cpu(cpu, mm_cpumask(mm))
1166 && per_cpu(xen_current_cr3, cpu) != __pa(mm->pgd))
1168 smp_call_function_single(cpu, drop_other_mm_ref, mm, 1);
1172 cpumask_copy(mask, mm_cpumask(mm));
1174 /* It's possible that a vcpu may have a stale reference to our
1175 cr3, because its in lazy mode, and it hasn't yet flushed
1176 its set of pending hypercalls yet. In this case, we can
1177 look at its actual current cr3 value, and force it to flush
1179 for_each_online_cpu(cpu) {
1180 if (per_cpu(xen_current_cr3, cpu) == __pa(mm->pgd))
1181 cpumask_set_cpu(cpu, mask);
1184 if (!cpumask_empty(mask))
1185 smp_call_function_many(mask, drop_other_mm_ref, mm, 1);
1186 free_cpumask_var(mask);
1189 static void xen_drop_mm_ref(struct mm_struct *mm)
1191 if (current->active_mm == mm)
1192 load_cr3(swapper_pg_dir);
1197 * While a process runs, Xen pins its pagetables, which means that the
1198 * hypervisor forces it to be read-only, and it controls all updates
1199 * to it. This means that all pagetable updates have to go via the
1200 * hypervisor, which is moderately expensive.
1202 * Since we're pulling the pagetable down, we switch to use init_mm,
1203 * unpin old process pagetable and mark it all read-write, which
1204 * allows further operations on it to be simple memory accesses.
1206 * The only subtle point is that another CPU may be still using the
1207 * pagetable because of lazy tlb flushing. This means we need need to
1208 * switch all CPUs off this pagetable before we can unpin it.
1210 void xen_exit_mmap(struct mm_struct *mm)
1212 get_cpu(); /* make sure we don't move around */
1213 xen_drop_mm_ref(mm);
1216 spin_lock(&mm->page_table_lock);
1218 /* pgd may not be pinned in the error exit path of execve */
1219 if (xen_page_pinned(mm->pgd))
1222 spin_unlock(&mm->page_table_lock);
1225 static __init void xen_pagetable_setup_start(pgd_t *base)
1229 static void xen_post_allocator_init(void);
1231 static __init void xen_pagetable_setup_done(pgd_t *base)
1233 xen_setup_shared_info();
1234 xen_post_allocator_init();
1237 static void xen_write_cr2(unsigned long cr2)
1239 percpu_read(xen_vcpu)->arch.cr2 = cr2;
1242 static unsigned long xen_read_cr2(void)
1244 return percpu_read(xen_vcpu)->arch.cr2;
1247 unsigned long xen_read_cr2_direct(void)
1249 return percpu_read(xen_vcpu_info.arch.cr2);
1252 static void xen_flush_tlb(void)
1254 struct mmuext_op *op;
1255 struct multicall_space mcs;
1259 mcs = xen_mc_entry(sizeof(*op));
1262 op->cmd = MMUEXT_TLB_FLUSH_LOCAL;
1263 MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
1265 xen_mc_issue(PARAVIRT_LAZY_MMU);
1270 static void xen_flush_tlb_single(unsigned long addr)
1272 struct mmuext_op *op;
1273 struct multicall_space mcs;
1277 mcs = xen_mc_entry(sizeof(*op));
1279 op->cmd = MMUEXT_INVLPG_LOCAL;
1280 op->arg1.linear_addr = addr & PAGE_MASK;
1281 MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
1283 xen_mc_issue(PARAVIRT_LAZY_MMU);
1288 static void xen_flush_tlb_others(const struct cpumask *cpus,
1289 struct mm_struct *mm, unsigned long va)
1292 struct mmuext_op op;
1293 DECLARE_BITMAP(mask, NR_CPUS);
1295 struct multicall_space mcs;
1297 if (cpumask_empty(cpus))
1298 return; /* nothing to do */
1300 mcs = xen_mc_entry(sizeof(*args));
1302 args->op.arg2.vcpumask = to_cpumask(args->mask);
1304 /* Remove us, and any offline CPUS. */
1305 cpumask_and(to_cpumask(args->mask), cpus, cpu_online_mask);
1306 cpumask_clear_cpu(smp_processor_id(), to_cpumask(args->mask));
1308 if (va == TLB_FLUSH_ALL) {
1309 args->op.cmd = MMUEXT_TLB_FLUSH_MULTI;
1311 args->op.cmd = MMUEXT_INVLPG_MULTI;
1312 args->op.arg1.linear_addr = va;
1315 MULTI_mmuext_op(mcs.mc, &args->op, 1, NULL, DOMID_SELF);
1317 xen_mc_issue(PARAVIRT_LAZY_MMU);
1320 static unsigned long xen_read_cr3(void)
1322 return percpu_read(xen_cr3);
1325 static void set_current_cr3(void *v)
1327 percpu_write(xen_current_cr3, (unsigned long)v);
1330 static void __xen_write_cr3(bool kernel, unsigned long cr3)
1332 struct mmuext_op *op;
1333 struct multicall_space mcs;
1337 mfn = pfn_to_mfn(PFN_DOWN(cr3));
1341 WARN_ON(mfn == 0 && kernel);
1343 mcs = __xen_mc_entry(sizeof(*op));
1346 op->cmd = kernel ? MMUEXT_NEW_BASEPTR : MMUEXT_NEW_USER_BASEPTR;
1349 MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
1352 percpu_write(xen_cr3, cr3);
1354 /* Update xen_current_cr3 once the batch has actually
1356 xen_mc_callback(set_current_cr3, (void *)cr3);
1360 static void xen_write_cr3(unsigned long cr3)
1362 BUG_ON(preemptible());
1364 xen_mc_batch(); /* disables interrupts */
1366 /* Update while interrupts are disabled, so its atomic with
1368 percpu_write(xen_cr3, cr3);
1370 __xen_write_cr3(true, cr3);
1372 #ifdef CONFIG_X86_64
1374 pgd_t *user_pgd = xen_get_user_pgd(__va(cr3));
1376 __xen_write_cr3(false, __pa(user_pgd));
1378 __xen_write_cr3(false, 0);
1382 xen_mc_issue(PARAVIRT_LAZY_CPU); /* interrupts restored */
1385 static int xen_pgd_alloc(struct mm_struct *mm)
1387 pgd_t *pgd = mm->pgd;
1390 BUG_ON(PagePinned(virt_to_page(pgd)));
1392 #ifdef CONFIG_X86_64
1394 struct page *page = virt_to_page(pgd);
1397 BUG_ON(page->private != 0);
1401 user_pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
1402 page->private = (unsigned long)user_pgd;
1404 if (user_pgd != NULL) {
1405 user_pgd[pgd_index(VSYSCALL_START)] =
1406 __pgd(__pa(level3_user_vsyscall) | _PAGE_TABLE);
1410 BUG_ON(PagePinned(virt_to_page(xen_get_user_pgd(pgd))));
1417 static void xen_pgd_free(struct mm_struct *mm, pgd_t *pgd)
1419 #ifdef CONFIG_X86_64
1420 pgd_t *user_pgd = xen_get_user_pgd(pgd);
1423 free_page((unsigned long)user_pgd);
1427 static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte)
1429 unsigned long pfn = pte_pfn(pte);
1431 #ifdef CONFIG_X86_32
1432 /* If there's an existing pte, then don't allow _PAGE_RW to be set */
1433 if (pte_val_ma(*ptep) & _PAGE_PRESENT)
1434 pte = __pte_ma(((pte_val_ma(*ptep) & _PAGE_RW) | ~_PAGE_RW) &
1439 * If the new pfn is within the range of the newly allocated
1440 * kernel pagetable, and it isn't being mapped into an
1441 * early_ioremap fixmap slot, make sure it is RO.
1443 if (!is_early_ioremap_ptep(ptep) &&
1444 pfn >= e820_table_start && pfn < e820_table_end)
1445 pte = pte_wrprotect(pte);
1450 /* Init-time set_pte while constructing initial pagetables, which
1451 doesn't allow RO pagetable pages to be remapped RW */
1452 static __init void xen_set_pte_init(pte_t *ptep, pte_t pte)
1454 pte = mask_rw_pte(ptep, pte);
1456 xen_set_pte(ptep, pte);
1459 static void pin_pagetable_pfn(unsigned cmd, unsigned long pfn)
1461 struct mmuext_op op;
1463 op.arg1.mfn = pfn_to_mfn(pfn);
1464 if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF))
1468 /* Early in boot, while setting up the initial pagetable, assume
1469 everything is pinned. */
1470 static __init void xen_alloc_pte_init(struct mm_struct *mm, unsigned long pfn)
1472 #ifdef CONFIG_FLATMEM
1473 BUG_ON(mem_map); /* should only be used early */
1475 make_lowmem_page_readonly(__va(PFN_PHYS(pfn)));
1476 pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE, pfn);
1479 /* Used for pmd and pud */
1480 static __init void xen_alloc_pmd_init(struct mm_struct *mm, unsigned long pfn)
1482 #ifdef CONFIG_FLATMEM
1483 BUG_ON(mem_map); /* should only be used early */
1485 make_lowmem_page_readonly(__va(PFN_PHYS(pfn)));
1488 /* Early release_pte assumes that all pts are pinned, since there's
1489 only init_mm and anything attached to that is pinned. */
1490 static __init void xen_release_pte_init(unsigned long pfn)
1492 pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, pfn);
1493 make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
1496 static __init void xen_release_pmd_init(unsigned long pfn)
1498 make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
1501 /* This needs to make sure the new pte page is pinned iff its being
1502 attached to a pinned pagetable. */
1503 static void xen_alloc_ptpage(struct mm_struct *mm, unsigned long pfn, unsigned level)
1505 struct page *page = pfn_to_page(pfn);
1507 if (PagePinned(virt_to_page(mm->pgd))) {
1508 SetPagePinned(page);
1510 if (!PageHighMem(page)) {
1511 make_lowmem_page_readonly(__va(PFN_PHYS((unsigned long)pfn)));
1512 if (level == PT_PTE && USE_SPLIT_PTLOCKS)
1513 pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE, pfn);
1515 /* make sure there are no stray mappings of
1517 kmap_flush_unused();
1522 static void xen_alloc_pte(struct mm_struct *mm, unsigned long pfn)
1524 xen_alloc_ptpage(mm, pfn, PT_PTE);
1527 static void xen_alloc_pmd(struct mm_struct *mm, unsigned long pfn)
1529 xen_alloc_ptpage(mm, pfn, PT_PMD);
1532 /* This should never happen until we're OK to use struct page */
1533 static void xen_release_ptpage(unsigned long pfn, unsigned level)
1535 struct page *page = pfn_to_page(pfn);
1537 if (PagePinned(page)) {
1538 if (!PageHighMem(page)) {
1539 if (level == PT_PTE && USE_SPLIT_PTLOCKS)
1540 pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, pfn);
1541 make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
1543 ClearPagePinned(page);
1547 static void xen_release_pte(unsigned long pfn)
1549 xen_release_ptpage(pfn, PT_PTE);
1552 static void xen_release_pmd(unsigned long pfn)
1554 xen_release_ptpage(pfn, PT_PMD);
1557 #if PAGETABLE_LEVELS == 4
1558 static void xen_alloc_pud(struct mm_struct *mm, unsigned long pfn)
1560 xen_alloc_ptpage(mm, pfn, PT_PUD);
1563 static void xen_release_pud(unsigned long pfn)
1565 xen_release_ptpage(pfn, PT_PUD);
1569 void __init xen_reserve_top(void)
1571 #ifdef CONFIG_X86_32
1572 unsigned long top = HYPERVISOR_VIRT_START;
1573 struct xen_platform_parameters pp;
1575 if (HYPERVISOR_xen_version(XENVER_platform_parameters, &pp) == 0)
1576 top = pp.virt_start;
1578 reserve_top_address(-top);
1579 #endif /* CONFIG_X86_32 */
1583 * Like __va(), but returns address in the kernel mapping (which is
1584 * all we have until the physical memory mapping has been set up.
1586 static void *__ka(phys_addr_t paddr)
1588 #ifdef CONFIG_X86_64
1589 return (void *)(paddr + __START_KERNEL_map);
1595 /* Convert a machine address to physical address */
1596 static unsigned long m2p(phys_addr_t maddr)
1600 maddr &= PTE_PFN_MASK;
1601 paddr = mfn_to_pfn(maddr >> PAGE_SHIFT) << PAGE_SHIFT;
1606 /* Convert a machine address to kernel virtual */
1607 static void *m2v(phys_addr_t maddr)
1609 return __ka(m2p(maddr));
1612 /* Set the page permissions on an identity-mapped pages */
1613 static void set_page_prot(void *addr, pgprot_t prot)
1615 unsigned long pfn = __pa(addr) >> PAGE_SHIFT;
1616 pte_t pte = pfn_pte(pfn, prot);
1618 if (HYPERVISOR_update_va_mapping((unsigned long)addr, pte, 0))
1622 static __init void xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn)
1624 unsigned pmdidx, pteidx;
1628 level1_ident_pgt = extend_brk(sizeof(pte_t) * LEVEL1_IDENT_ENTRIES,
1633 for (pmdidx = 0; pmdidx < PTRS_PER_PMD && pfn < max_pfn; pmdidx++) {
1636 /* Reuse or allocate a page of ptes */
1637 if (pmd_present(pmd[pmdidx]))
1638 pte_page = m2v(pmd[pmdidx].pmd);
1640 /* Check for free pte pages */
1641 if (ident_pte == LEVEL1_IDENT_ENTRIES)
1644 pte_page = &level1_ident_pgt[ident_pte];
1645 ident_pte += PTRS_PER_PTE;
1647 pmd[pmdidx] = __pmd(__pa(pte_page) | _PAGE_TABLE);
1650 /* Install mappings */
1651 for (pteidx = 0; pteidx < PTRS_PER_PTE; pteidx++, pfn++) {
1654 if (!pte_none(pte_page[pteidx]))
1657 pte = pfn_pte(pfn, PAGE_KERNEL_EXEC);
1658 pte_page[pteidx] = pte;
1662 for (pteidx = 0; pteidx < ident_pte; pteidx += PTRS_PER_PTE)
1663 set_page_prot(&level1_ident_pgt[pteidx], PAGE_KERNEL_RO);
1665 set_page_prot(pmd, PAGE_KERNEL_RO);
1668 void __init xen_setup_machphys_mapping(void)
1670 struct xen_machphys_mapping mapping;
1671 unsigned long machine_to_phys_nr_ents;
1673 if (HYPERVISOR_memory_op(XENMEM_machphys_mapping, &mapping) == 0) {
1674 machine_to_phys_mapping = (unsigned long *)mapping.v_start;
1675 machine_to_phys_nr_ents = mapping.max_mfn + 1;
1677 machine_to_phys_nr_ents = MACH2PHYS_NR_ENTRIES;
1679 machine_to_phys_order = fls(machine_to_phys_nr_ents - 1);
1682 #ifdef CONFIG_X86_64
1683 static void convert_pfn_mfn(void *v)
1688 /* All levels are converted the same way, so just treat them
1690 for (i = 0; i < PTRS_PER_PTE; i++)
1691 pte[i] = xen_make_pte(pte[i].pte);
1695 * Set up the inital kernel pagetable.
1697 * We can construct this by grafting the Xen provided pagetable into
1698 * head_64.S's preconstructed pagetables. We copy the Xen L2's into
1699 * level2_ident_pgt, level2_kernel_pgt and level2_fixmap_pgt. This
1700 * means that only the kernel has a physical mapping to start with -
1701 * but that's enough to get __va working. We need to fill in the rest
1702 * of the physical mapping once some sort of allocator has been set
1705 __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
1706 unsigned long max_pfn)
1711 /* max_pfn_mapped is the last pfn mapped in the initial memory
1712 * mappings. Considering that on Xen after the kernel mappings we
1713 * have the mappings of some pages that don't exist in pfn space, we
1714 * set max_pfn_mapped to the last real pfn mapped. */
1715 max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->mfn_list));
1717 /* Zap identity mapping */
1718 init_level4_pgt[0] = __pgd(0);
1720 /* Pre-constructed entries are in pfn, so convert to mfn */
1721 convert_pfn_mfn(init_level4_pgt);
1722 convert_pfn_mfn(level3_ident_pgt);
1723 convert_pfn_mfn(level3_kernel_pgt);
1725 l3 = m2v(pgd[pgd_index(__START_KERNEL_map)].pgd);
1726 l2 = m2v(l3[pud_index(__START_KERNEL_map)].pud);
1728 memcpy(level2_ident_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
1729 memcpy(level2_kernel_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
1731 l3 = m2v(pgd[pgd_index(__START_KERNEL_map + PMD_SIZE)].pgd);
1732 l2 = m2v(l3[pud_index(__START_KERNEL_map + PMD_SIZE)].pud);
1733 memcpy(level2_fixmap_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
1735 /* Set up identity map */
1736 xen_map_identity_early(level2_ident_pgt, max_pfn);
1738 /* Make pagetable pieces RO */
1739 set_page_prot(init_level4_pgt, PAGE_KERNEL_RO);
1740 set_page_prot(level3_ident_pgt, PAGE_KERNEL_RO);
1741 set_page_prot(level3_kernel_pgt, PAGE_KERNEL_RO);
1742 set_page_prot(level3_user_vsyscall, PAGE_KERNEL_RO);
1743 set_page_prot(level2_kernel_pgt, PAGE_KERNEL_RO);
1744 set_page_prot(level2_fixmap_pgt, PAGE_KERNEL_RO);
1746 /* Pin down new L4 */
1747 pin_pagetable_pfn(MMUEXT_PIN_L4_TABLE,
1748 PFN_DOWN(__pa_symbol(init_level4_pgt)));
1750 /* Unpin Xen-provided one */
1751 pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd)));
1754 pgd = init_level4_pgt;
1757 * At this stage there can be no user pgd, and no page
1758 * structure to attach it to, so make sure we just set kernel
1762 __xen_write_cr3(true, __pa(pgd));
1763 xen_mc_issue(PARAVIRT_LAZY_CPU);
1765 memblock_x86_reserve_range(__pa(xen_start_info->pt_base),
1766 __pa(xen_start_info->pt_base +
1767 xen_start_info->nr_pt_frames * PAGE_SIZE),
1772 #else /* !CONFIG_X86_64 */
1773 static RESERVE_BRK_ARRAY(pmd_t, initial_kernel_pmd, PTRS_PER_PMD);
1774 static RESERVE_BRK_ARRAY(pmd_t, swapper_kernel_pmd, PTRS_PER_PMD);
1776 static __init void xen_write_cr3_init(unsigned long cr3)
1778 unsigned long pfn = PFN_DOWN(__pa(swapper_pg_dir));
1780 BUG_ON(read_cr3() != __pa(initial_page_table));
1781 BUG_ON(cr3 != __pa(swapper_pg_dir));
1784 * We are switching to swapper_pg_dir for the first time (from
1785 * initial_page_table) and therefore need to mark that page
1786 * read-only and then pin it.
1788 * Xen disallows sharing of kernel PMDs for PAE
1789 * guests. Therefore we must copy the kernel PMD from
1790 * initial_page_table into a new kernel PMD to be used in
1793 swapper_kernel_pmd =
1794 extend_brk(sizeof(pmd_t) * PTRS_PER_PMD, PAGE_SIZE);
1795 memcpy(swapper_kernel_pmd, initial_kernel_pmd,
1796 sizeof(pmd_t) * PTRS_PER_PMD);
1797 swapper_pg_dir[KERNEL_PGD_BOUNDARY] =
1798 __pgd(__pa(swapper_kernel_pmd) | _PAGE_PRESENT);
1799 set_page_prot(swapper_kernel_pmd, PAGE_KERNEL_RO);
1801 set_page_prot(swapper_pg_dir, PAGE_KERNEL_RO);
1803 pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, pfn);
1805 pin_pagetable_pfn(MMUEXT_UNPIN_TABLE,
1806 PFN_DOWN(__pa(initial_page_table)));
1807 set_page_prot(initial_page_table, PAGE_KERNEL);
1808 set_page_prot(initial_kernel_pmd, PAGE_KERNEL);
1810 pv_mmu_ops.write_cr3 = &xen_write_cr3;
1813 __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
1814 unsigned long max_pfn)
1818 initial_kernel_pmd =
1819 extend_brk(sizeof(pmd_t) * PTRS_PER_PMD, PAGE_SIZE);
1821 max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->mfn_list));
1823 kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd);
1824 memcpy(initial_kernel_pmd, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD);
1826 xen_map_identity_early(initial_kernel_pmd, max_pfn);
1828 memcpy(initial_page_table, pgd, sizeof(pgd_t) * PTRS_PER_PGD);
1829 initial_page_table[KERNEL_PGD_BOUNDARY] =
1830 __pgd(__pa(initial_kernel_pmd) | _PAGE_PRESENT);
1832 set_page_prot(initial_kernel_pmd, PAGE_KERNEL_RO);
1833 set_page_prot(initial_page_table, PAGE_KERNEL_RO);
1834 set_page_prot(empty_zero_page, PAGE_KERNEL_RO);
1836 pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd)));
1838 pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE,
1839 PFN_DOWN(__pa(initial_page_table)));
1840 xen_write_cr3(__pa(initial_page_table));
1842 memblock_x86_reserve_range(__pa(xen_start_info->pt_base),
1843 __pa(xen_start_info->pt_base +
1844 xen_start_info->nr_pt_frames * PAGE_SIZE),
1847 return initial_page_table;
1849 #endif /* CONFIG_X86_64 */
1851 static unsigned char dummy_mapping[PAGE_SIZE] __page_aligned_bss;
1853 static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot)
1857 phys >>= PAGE_SHIFT;
1860 case FIX_BTMAP_END ... FIX_BTMAP_BEGIN:
1861 #ifdef CONFIG_X86_F00F_BUG
1864 #ifdef CONFIG_X86_32
1867 # ifdef CONFIG_HIGHMEM
1868 case FIX_KMAP_BEGIN ... FIX_KMAP_END:
1871 case VSYSCALL_LAST_PAGE ... VSYSCALL_FIRST_PAGE:
1873 case FIX_TEXT_POKE0:
1874 case FIX_TEXT_POKE1:
1875 /* All local page mappings */
1876 pte = pfn_pte(phys, prot);
1879 #ifdef CONFIG_X86_LOCAL_APIC
1880 case FIX_APIC_BASE: /* maps dummy local APIC */
1881 pte = pfn_pte(PFN_DOWN(__pa(dummy_mapping)), PAGE_KERNEL);
1885 #ifdef CONFIG_X86_IO_APIC
1886 case FIX_IO_APIC_BASE_0 ... FIX_IO_APIC_BASE_END:
1888 * We just don't map the IO APIC - all access is via
1889 * hypercalls. Keep the address in the pte for reference.
1891 pte = pfn_pte(PFN_DOWN(__pa(dummy_mapping)), PAGE_KERNEL);
1895 case FIX_PARAVIRT_BOOTMAP:
1896 /* This is an MFN, but it isn't an IO mapping from the
1898 pte = mfn_pte(phys, prot);
1902 /* By default, set_fixmap is used for hardware mappings */
1903 pte = mfn_pte(phys, __pgprot(pgprot_val(prot) | _PAGE_IOMAP));
1907 __native_set_fixmap(idx, pte);
1909 #ifdef CONFIG_X86_64
1910 /* Replicate changes to map the vsyscall page into the user
1911 pagetable vsyscall mapping. */
1912 if (idx >= VSYSCALL_LAST_PAGE && idx <= VSYSCALL_FIRST_PAGE) {
1913 unsigned long vaddr = __fix_to_virt(idx);
1914 set_pte_vaddr_pud(level3_user_vsyscall, vaddr, pte);
1919 __init void xen_ident_map_ISA(void)
1924 * If we're dom0, then linear map the ISA machine addresses into
1925 * the kernel's address space.
1927 if (!xen_initial_domain())
1930 xen_raw_printk("Xen: setup ISA identity maps\n");
1932 for (pa = ISA_START_ADDRESS; pa < ISA_END_ADDRESS; pa += PAGE_SIZE) {
1933 pte_t pte = mfn_pte(PFN_DOWN(pa), PAGE_KERNEL_IO);
1935 if (HYPERVISOR_update_va_mapping(PAGE_OFFSET + pa, pte, 0))
1942 static __init void xen_post_allocator_init(void)
1944 pv_mmu_ops.set_pte = xen_set_pte;
1945 pv_mmu_ops.set_pmd = xen_set_pmd;
1946 pv_mmu_ops.set_pud = xen_set_pud;
1947 #if PAGETABLE_LEVELS == 4
1948 pv_mmu_ops.set_pgd = xen_set_pgd;
1951 /* This will work as long as patching hasn't happened yet
1952 (which it hasn't) */
1953 pv_mmu_ops.alloc_pte = xen_alloc_pte;
1954 pv_mmu_ops.alloc_pmd = xen_alloc_pmd;
1955 pv_mmu_ops.release_pte = xen_release_pte;
1956 pv_mmu_ops.release_pmd = xen_release_pmd;
1957 #if PAGETABLE_LEVELS == 4
1958 pv_mmu_ops.alloc_pud = xen_alloc_pud;
1959 pv_mmu_ops.release_pud = xen_release_pud;
1962 #ifdef CONFIG_X86_64
1963 SetPagePinned(virt_to_page(level3_user_vsyscall));
1965 xen_mark_init_mm_pinned();
1968 static void xen_leave_lazy_mmu(void)
1972 paravirt_leave_lazy_mmu();
1976 static const struct pv_mmu_ops xen_mmu_ops __initdata = {
1977 .read_cr2 = xen_read_cr2,
1978 .write_cr2 = xen_write_cr2,
1980 .read_cr3 = xen_read_cr3,
1981 #ifdef CONFIG_X86_32
1982 .write_cr3 = xen_write_cr3_init,
1984 .write_cr3 = xen_write_cr3,
1987 .flush_tlb_user = xen_flush_tlb,
1988 .flush_tlb_kernel = xen_flush_tlb,
1989 .flush_tlb_single = xen_flush_tlb_single,
1990 .flush_tlb_others = xen_flush_tlb_others,
1992 .pte_update = paravirt_nop,
1993 .pte_update_defer = paravirt_nop,
1995 .pgd_alloc = xen_pgd_alloc,
1996 .pgd_free = xen_pgd_free,
1998 .alloc_pte = xen_alloc_pte_init,
1999 .release_pte = xen_release_pte_init,
2000 .alloc_pmd = xen_alloc_pmd_init,
2001 .release_pmd = xen_release_pmd_init,
2003 .set_pte = xen_set_pte_init,
2004 .set_pte_at = xen_set_pte_at,
2005 .set_pmd = xen_set_pmd_hyper,
2007 .ptep_modify_prot_start = __ptep_modify_prot_start,
2008 .ptep_modify_prot_commit = __ptep_modify_prot_commit,
2010 .pte_val = PV_CALLEE_SAVE(xen_pte_val),
2011 .pgd_val = PV_CALLEE_SAVE(xen_pgd_val),
2013 .make_pte = PV_CALLEE_SAVE(xen_make_pte),
2014 .make_pgd = PV_CALLEE_SAVE(xen_make_pgd),
2016 #ifdef CONFIG_X86_PAE
2017 .set_pte_atomic = xen_set_pte_atomic,
2018 .pte_clear = xen_pte_clear,
2019 .pmd_clear = xen_pmd_clear,
2020 #endif /* CONFIG_X86_PAE */
2021 .set_pud = xen_set_pud_hyper,
2023 .make_pmd = PV_CALLEE_SAVE(xen_make_pmd),
2024 .pmd_val = PV_CALLEE_SAVE(xen_pmd_val),
2026 #if PAGETABLE_LEVELS == 4
2027 .pud_val = PV_CALLEE_SAVE(xen_pud_val),
2028 .make_pud = PV_CALLEE_SAVE(xen_make_pud),
2029 .set_pgd = xen_set_pgd_hyper,
2031 .alloc_pud = xen_alloc_pmd_init,
2032 .release_pud = xen_release_pmd_init,
2033 #endif /* PAGETABLE_LEVELS == 4 */
2035 .activate_mm = xen_activate_mm,
2036 .dup_mmap = xen_dup_mmap,
2037 .exit_mmap = xen_exit_mmap,
2040 .enter = paravirt_enter_lazy_mmu,
2041 .leave = xen_leave_lazy_mmu,
2044 .set_fixmap = xen_set_fixmap,
2047 void __init xen_init_mmu_ops(void)
2049 x86_init.paging.pagetable_setup_start = xen_pagetable_setup_start;
2050 x86_init.paging.pagetable_setup_done = xen_pagetable_setup_done;
2051 pv_mmu_ops = xen_mmu_ops;
2053 memset(dummy_mapping, 0xff, PAGE_SIZE);
2056 /* Protected by xen_reservation_lock. */
2057 #define MAX_CONTIG_ORDER 9 /* 2MB */
2058 static unsigned long discontig_frames[1<<MAX_CONTIG_ORDER];
2060 #define VOID_PTE (mfn_pte(0, __pgprot(0)))
2061 static void xen_zap_pfn_range(unsigned long vaddr, unsigned int order,
2062 unsigned long *in_frames,
2063 unsigned long *out_frames)
2066 struct multicall_space mcs;
2069 for (i = 0; i < (1UL<<order); i++, vaddr += PAGE_SIZE) {
2070 mcs = __xen_mc_entry(0);
2073 in_frames[i] = virt_to_mfn(vaddr);
2075 MULTI_update_va_mapping(mcs.mc, vaddr, VOID_PTE, 0);
2076 set_phys_to_machine(virt_to_pfn(vaddr), INVALID_P2M_ENTRY);
2079 out_frames[i] = virt_to_pfn(vaddr);
2085 * Update the pfn-to-mfn mappings for a virtual address range, either to
2086 * point to an array of mfns, or contiguously from a single starting
2089 static void xen_remap_exchanged_ptes(unsigned long vaddr, int order,
2090 unsigned long *mfns,
2091 unsigned long first_mfn)
2098 limit = 1u << order;
2099 for (i = 0; i < limit; i++, vaddr += PAGE_SIZE) {
2100 struct multicall_space mcs;
2103 mcs = __xen_mc_entry(0);
2107 mfn = first_mfn + i;
2109 if (i < (limit - 1))
2113 flags = UVMF_INVLPG | UVMF_ALL;
2115 flags = UVMF_TLB_FLUSH | UVMF_ALL;
2118 MULTI_update_va_mapping(mcs.mc, vaddr,
2119 mfn_pte(mfn, PAGE_KERNEL), flags);
2121 set_phys_to_machine(virt_to_pfn(vaddr), mfn);
2128 * Perform the hypercall to exchange a region of our pfns to point to
2129 * memory with the required contiguous alignment. Takes the pfns as
2130 * input, and populates mfns as output.
2132 * Returns a success code indicating whether the hypervisor was able to
2133 * satisfy the request or not.
2135 static int xen_exchange_memory(unsigned long extents_in, unsigned int order_in,
2136 unsigned long *pfns_in,
2137 unsigned long extents_out,
2138 unsigned int order_out,
2139 unsigned long *mfns_out,
2140 unsigned int address_bits)
2145 struct xen_memory_exchange exchange = {
2147 .nr_extents = extents_in,
2148 .extent_order = order_in,
2149 .extent_start = pfns_in,
2153 .nr_extents = extents_out,
2154 .extent_order = order_out,
2155 .extent_start = mfns_out,
2156 .address_bits = address_bits,
2161 BUG_ON(extents_in << order_in != extents_out << order_out);
2163 rc = HYPERVISOR_memory_op(XENMEM_exchange, &exchange);
2164 success = (exchange.nr_exchanged == extents_in);
2166 BUG_ON(!success && ((exchange.nr_exchanged != 0) || (rc == 0)));
2167 BUG_ON(success && (rc != 0));
2172 int xen_create_contiguous_region(unsigned long vstart, unsigned int order,
2173 unsigned int address_bits)
2175 unsigned long *in_frames = discontig_frames, out_frame;
2176 unsigned long flags;
2180 * Currently an auto-translated guest will not perform I/O, nor will
2181 * it require PAE page directories below 4GB. Therefore any calls to
2182 * this function are redundant and can be ignored.
2185 if (xen_feature(XENFEAT_auto_translated_physmap))
2188 if (unlikely(order > MAX_CONTIG_ORDER))
2191 memset((void *) vstart, 0, PAGE_SIZE << order);
2193 spin_lock_irqsave(&xen_reservation_lock, flags);
2195 /* 1. Zap current PTEs, remembering MFNs. */
2196 xen_zap_pfn_range(vstart, order, in_frames, NULL);
2198 /* 2. Get a new contiguous memory extent. */
2199 out_frame = virt_to_pfn(vstart);
2200 success = xen_exchange_memory(1UL << order, 0, in_frames,
2201 1, order, &out_frame,
2204 /* 3. Map the new extent in place of old pages. */
2206 xen_remap_exchanged_ptes(vstart, order, NULL, out_frame);
2208 xen_remap_exchanged_ptes(vstart, order, in_frames, 0);
2210 spin_unlock_irqrestore(&xen_reservation_lock, flags);
2212 return success ? 0 : -ENOMEM;
2214 EXPORT_SYMBOL_GPL(xen_create_contiguous_region);
2216 void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order)
2218 unsigned long *out_frames = discontig_frames, in_frame;
2219 unsigned long flags;
2222 if (xen_feature(XENFEAT_auto_translated_physmap))
2225 if (unlikely(order > MAX_CONTIG_ORDER))
2228 memset((void *) vstart, 0, PAGE_SIZE << order);
2230 spin_lock_irqsave(&xen_reservation_lock, flags);
2232 /* 1. Find start MFN of contiguous extent. */
2233 in_frame = virt_to_mfn(vstart);
2235 /* 2. Zap current PTEs. */
2236 xen_zap_pfn_range(vstart, order, NULL, out_frames);
2238 /* 3. Do the exchange for non-contiguous MFNs. */
2239 success = xen_exchange_memory(1, order, &in_frame, 1UL << order,
2242 /* 4. Map new pages in place of old pages. */
2244 xen_remap_exchanged_ptes(vstart, order, out_frames, 0);
2246 xen_remap_exchanged_ptes(vstart, order, NULL, in_frame);
2248 spin_unlock_irqrestore(&xen_reservation_lock, flags);
2250 EXPORT_SYMBOL_GPL(xen_destroy_contiguous_region);
2252 #ifdef CONFIG_XEN_PVHVM
2253 static void xen_hvm_exit_mmap(struct mm_struct *mm)
2255 struct xen_hvm_pagetable_dying a;
2258 a.domid = DOMID_SELF;
2259 a.gpa = __pa(mm->pgd);
2260 rc = HYPERVISOR_hvm_op(HVMOP_pagetable_dying, &a);
2261 WARN_ON_ONCE(rc < 0);
2264 static int is_pagetable_dying_supported(void)
2266 struct xen_hvm_pagetable_dying a;
2269 a.domid = DOMID_SELF;
2271 rc = HYPERVISOR_hvm_op(HVMOP_pagetable_dying, &a);
2273 printk(KERN_DEBUG "HVMOP_pagetable_dying not supported\n");
2279 void __init xen_hvm_init_mmu_ops(void)
2281 if (is_pagetable_dying_supported())
2282 pv_mmu_ops.exit_mmap = xen_hvm_exit_mmap;
2286 #define REMAP_BATCH_SIZE 16
2291 struct mmu_update *mmu_update;
2294 static int remap_area_mfn_pte_fn(pte_t *ptep, pgtable_t token,
2295 unsigned long addr, void *data)
2297 struct remap_data *rmd = data;
2298 pte_t pte = pte_mkspecial(pfn_pte(rmd->mfn++, rmd->prot));
2300 rmd->mmu_update->ptr = arbitrary_virt_to_machine(ptep).maddr;
2301 rmd->mmu_update->val = pte_val_ma(pte);
2307 int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
2309 unsigned long mfn, int nr,
2310 pgprot_t prot, unsigned domid)
2312 struct remap_data rmd;
2313 struct mmu_update mmu_update[REMAP_BATCH_SIZE];
2315 unsigned long range;
2318 prot = __pgprot(pgprot_val(prot) | _PAGE_IOMAP);
2320 BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_RESERVED | VM_IO)) ==
2321 (VM_PFNMAP | VM_RESERVED | VM_IO)));
2327 batch = min(REMAP_BATCH_SIZE, nr);
2328 range = (unsigned long)batch << PAGE_SHIFT;
2330 rmd.mmu_update = mmu_update;
2331 err = apply_to_page_range(vma->vm_mm, addr, range,
2332 remap_area_mfn_pte_fn, &rmd);
2337 if (HYPERVISOR_mmu_update(mmu_update, batch, NULL, domid) < 0)
2351 EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
2353 #ifdef CONFIG_XEN_DEBUG_FS
2355 static struct dentry *d_mmu_debug;
2357 static int __init xen_mmu_debugfs(void)
2359 struct dentry *d_xen = xen_init_debugfs();
2364 d_mmu_debug = debugfs_create_dir("mmu", d_xen);
2366 debugfs_create_u8("zero_stats", 0644, d_mmu_debug, &zero_stats);
2368 debugfs_create_u32("pgd_update", 0444, d_mmu_debug, &mmu_stats.pgd_update);
2369 debugfs_create_u32("pgd_update_pinned", 0444, d_mmu_debug,
2370 &mmu_stats.pgd_update_pinned);
2371 debugfs_create_u32("pgd_update_batched", 0444, d_mmu_debug,
2372 &mmu_stats.pgd_update_pinned);
2374 debugfs_create_u32("pud_update", 0444, d_mmu_debug, &mmu_stats.pud_update);
2375 debugfs_create_u32("pud_update_pinned", 0444, d_mmu_debug,
2376 &mmu_stats.pud_update_pinned);
2377 debugfs_create_u32("pud_update_batched", 0444, d_mmu_debug,
2378 &mmu_stats.pud_update_pinned);
2380 debugfs_create_u32("pmd_update", 0444, d_mmu_debug, &mmu_stats.pmd_update);
2381 debugfs_create_u32("pmd_update_pinned", 0444, d_mmu_debug,
2382 &mmu_stats.pmd_update_pinned);
2383 debugfs_create_u32("pmd_update_batched", 0444, d_mmu_debug,
2384 &mmu_stats.pmd_update_pinned);
2386 debugfs_create_u32("pte_update", 0444, d_mmu_debug, &mmu_stats.pte_update);
2387 // debugfs_create_u32("pte_update_pinned", 0444, d_mmu_debug,
2388 // &mmu_stats.pte_update_pinned);
2389 debugfs_create_u32("pte_update_batched", 0444, d_mmu_debug,
2390 &mmu_stats.pte_update_pinned);
2392 debugfs_create_u32("mmu_update", 0444, d_mmu_debug, &mmu_stats.mmu_update);
2393 debugfs_create_u32("mmu_update_extended", 0444, d_mmu_debug,
2394 &mmu_stats.mmu_update_extended);
2395 xen_debugfs_create_u32_array("mmu_update_histo", 0444, d_mmu_debug,
2396 mmu_stats.mmu_update_histo, 20);
2398 debugfs_create_u32("set_pte_at", 0444, d_mmu_debug, &mmu_stats.set_pte_at);
2399 debugfs_create_u32("set_pte_at_batched", 0444, d_mmu_debug,
2400 &mmu_stats.set_pte_at_batched);
2401 debugfs_create_u32("set_pte_at_current", 0444, d_mmu_debug,
2402 &mmu_stats.set_pte_at_current);
2403 debugfs_create_u32("set_pte_at_kernel", 0444, d_mmu_debug,
2404 &mmu_stats.set_pte_at_kernel);
2406 debugfs_create_u32("prot_commit", 0444, d_mmu_debug, &mmu_stats.prot_commit);
2407 debugfs_create_u32("prot_commit_batched", 0444, d_mmu_debug,
2408 &mmu_stats.prot_commit_batched);
2412 fs_initcall(xen_mmu_debugfs);
2414 #endif /* CONFIG_XEN_DEBUG_FS */