diff options
Diffstat (limited to 'arch/x86/xen/mmu.c')
| -rw-r--r-- | arch/x86/xen/mmu.c | 694 |
1 files changed, 517 insertions, 177 deletions
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 58a0e46c404..e8a1201c329 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -47,6 +47,7 @@ #include <linux/gfp.h> #include <linux/memblock.h> #include <linux/seq_file.h> +#include <linux/crash_dump.h> #include <trace/events/xen.h> @@ -84,6 +85,7 @@ */ DEFINE_SPINLOCK(xen_reservation_lock); +#ifdef CONFIG_X86_32 /* * Identity map, in addition to plain kernel map. This needs to be * large enough to allocate page table pages to allocate the rest. @@ -91,7 +93,7 @@ DEFINE_SPINLOCK(xen_reservation_lock); */ #define LEVEL1_IDENT_ENTRIES (PTRS_PER_PTE * 4) static RESERVE_BRK_ARRAY(pte_t, level1_ident_pgt, LEVEL1_IDENT_ENTRIES); - +#endif #ifdef CONFIG_X86_64 /* l3 pud for userspace vsyscall mapping */ static pud_t level3_user_vsyscall[PTRS_PER_PUD] __page_aligned_bss; @@ -308,8 +310,20 @@ static bool xen_batched_set_pte(pte_t *ptep, pte_t pteval) static inline void __xen_set_pte(pte_t *ptep, pte_t pteval) { - if (!xen_batched_set_pte(ptep, pteval)) - native_set_pte(ptep, pteval); + if (!xen_batched_set_pte(ptep, pteval)) { + /* + * Could call native_set_pte() here and trap and + * emulate the PTE write but with 32-bit guests this + * needs two traps (one for each of the two 32-bit + * words in the PTE) so do one hypercall directly + * instead. + */ + struct mmu_update u; + + u.ptr = virt_to_machine(ptep).maddr | MMU_NORMAL_PT_UPDATE; + u.val = pte_val_ma(pteval); + HYPERVISOR_mmu_update(&u, 1, NULL, DOMID_SELF); + } } static void xen_set_pte(pte_t *ptep, pte_t pteval) @@ -353,8 +367,13 @@ static pteval_t pte_mfn_to_pfn(pteval_t val) { if (val & _PAGE_PRESENT) { unsigned long mfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT; + unsigned long pfn = mfn_to_pfn(mfn); + pteval_t flags = val & PTE_FLAGS_MASK; - val = ((pteval_t)mfn_to_pfn(mfn) << PAGE_SHIFT) | flags; + if (unlikely(pfn == ~0)) + val = flags & ~_PAGE_PRESENT; + else + val = ((pteval_t)pfn << PAGE_SHIFT) | flags; } return val; @@ -412,16 +431,16 @@ static pteval_t iomap_pte(pteval_t val) return val; } -static pteval_t xen_pte_val(pte_t pte) +__visible pteval_t xen_pte_val(pte_t pte) { pteval_t pteval = pte.pte; - +#if 0 /* If this is a WC pte, convert back from Xen WC to Linux WC */ if ((pteval & (_PAGE_PAT | _PAGE_PCD | _PAGE_PWT)) == _PAGE_PAT) { WARN_ON(!pat_enabled); pteval = (pteval & ~_PAGE_PAT) | _PAGE_PWT; } - +#endif if (xen_initial_domain() && (pteval & _PAGE_IOMAP)) return pteval; @@ -429,7 +448,7 @@ static pteval_t xen_pte_val(pte_t pte) } PV_CALLEE_SAVE_REGS_THUNK(xen_pte_val); -static pgdval_t xen_pgd_val(pgd_t pgd) +__visible pgdval_t xen_pgd_val(pgd_t pgd) { return pte_mfn_to_pfn(pgd.pgd); } @@ -449,8 +468,8 @@ PV_CALLEE_SAVE_REGS_THUNK(xen_pgd_val); * 3 PCD PWT UC UC UC * 4 PAT WB WC WB * 5 PAT PWT WC WP WT - * 6 PAT PCD UC- UC UC- - * 7 PAT PCD PWT UC UC UC + * 6 PAT PCD UC- rsv UC- + * 7 PAT PCD PWT UC rsv UC */ void xen_set_pat(u64 pat) @@ -460,10 +479,10 @@ void xen_set_pat(u64 pat) WARN_ON(pat != 0x0007010600070106ull); } -static pte_t xen_make_pte(pteval_t pte) +__visible pte_t xen_make_pte(pteval_t pte) { phys_addr_t addr = (pte & PTE_PFN_MASK); - +#if 0 /* If Linux is trying to set a WC pte, then map to the Xen WC. * If _PAGE_PAT is set, then it probably means it is really * _PAGE_PSE, so avoid fiddling with the PAT mapping and hope @@ -476,7 +495,7 @@ static pte_t xen_make_pte(pteval_t pte) if ((pte & (_PAGE_PCD | _PAGE_PWT)) == _PAGE_PWT) pte = (pte & ~(_PAGE_PCD | _PAGE_PWT)) | _PAGE_PAT; } - +#endif /* * Unprivileged domains are allowed to do IOMAPpings for * PCI passthrough, but not map ISA space. The ISA @@ -495,14 +514,14 @@ static pte_t xen_make_pte(pteval_t pte) } PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte); -static pgd_t xen_make_pgd(pgdval_t pgd) +__visible 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); -static pmdval_t xen_pmd_val(pmd_t pmd) +__visible pmdval_t xen_pmd_val(pmd_t pmd) { return pte_mfn_to_pfn(pmd.pmd); } @@ -561,7 +580,7 @@ static void xen_pmd_clear(pmd_t *pmdp) } #endif /* CONFIG_X86_PAE */ -static pmd_t xen_make_pmd(pmdval_t pmd) +__visible pmd_t xen_make_pmd(pmdval_t pmd) { pmd = pte_pfn_to_mfn(pmd); return native_make_pmd(pmd); @@ -569,13 +588,13 @@ static pmd_t xen_make_pmd(pmdval_t pmd) PV_CALLEE_SAVE_REGS_THUNK(xen_make_pmd); #if PAGETABLE_LEVELS == 4 -static pudval_t xen_pud_val(pud_t pud) +__visible pudval_t xen_pud_val(pud_t pud) { return pte_mfn_to_pfn(pud.pud); } PV_CALLEE_SAVE_REGS_THUNK(xen_pud_val); -static pud_t xen_make_pud(pudval_t pud) +__visible pud_t xen_make_pud(pudval_t pud) { pud = pte_pfn_to_mfn(pud); @@ -777,8 +796,8 @@ 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); +#if USE_SPLIT_PTE_PTLOCKS + ptl = ptlock_ptr(page); spin_lock_nest_lock(ptl, &mm->page_table_lock); #endif @@ -1071,14 +1090,14 @@ 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); + active_mm = this_cpu_read(cpu_tlbstate.active_mm); - if (active_mm == mm && percpu_read(cpu_tlbstate.state) != TLBSTATE_OK) + if (active_mm == mm && this_cpu_read(cpu_tlbstate.state) != TLBSTATE_OK) 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)) + if (this_cpu_read(xen_current_cr3) == __pa(mm->pgd)) load_cr3(swapper_pg_dir); } @@ -1157,47 +1176,127 @@ static void xen_exit_mmap(struct mm_struct *mm) spin_unlock(&mm->page_table_lock); } -static void __init xen_pagetable_setup_start(pgd_t *base) -{ -} +static void xen_post_allocator_init(void); -static __init void xen_mapping_pagetable_reserve(u64 start, u64 end) +#ifdef CONFIG_X86_64 +static void __init xen_cleanhighmap(unsigned long vaddr, + unsigned long vaddr_end) { - /* reserve the range used */ - native_pagetable_reserve(start, end); + unsigned long kernel_end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1; + pmd_t *pmd = level2_kernel_pgt + pmd_index(vaddr); - /* set as RW the rest */ - printk(KERN_DEBUG "xen: setting RW the range %llx - %llx\n", end, - PFN_PHYS(pgt_buf_top)); - while (end < PFN_PHYS(pgt_buf_top)) { - make_lowmem_page_readwrite(__va(end)); - end += PAGE_SIZE; + /* NOTE: The loop is more greedy than the cleanup_highmap variant. + * We include the PMD passed in on _both_ boundaries. */ + for (; vaddr <= vaddr_end && (pmd < (level2_kernel_pgt + PAGE_SIZE)); + pmd++, vaddr += PMD_SIZE) { + if (pmd_none(*pmd)) + continue; + if (vaddr < (unsigned long) _text || vaddr > kernel_end) + set_pmd(pmd, __pmd(0)); } + /* In case we did something silly, we should crash in this function + * instead of somewhere later and be confusing. */ + xen_mc_flush(); } +static void __init xen_pagetable_p2m_copy(void) +{ + unsigned long size; + unsigned long addr; + unsigned long new_mfn_list; -static void xen_post_allocator_init(void); + if (xen_feature(XENFEAT_auto_translated_physmap)) + return; -static void __init xen_pagetable_setup_done(pgd_t *base) + size = PAGE_ALIGN(xen_start_info->nr_pages * sizeof(unsigned long)); + + new_mfn_list = xen_revector_p2m_tree(); + /* No memory or already called. */ + if (!new_mfn_list || new_mfn_list == xen_start_info->mfn_list) + return; + + /* using __ka address and sticking INVALID_P2M_ENTRY! */ + memset((void *)xen_start_info->mfn_list, 0xff, size); + + /* We should be in __ka space. */ + BUG_ON(xen_start_info->mfn_list < __START_KERNEL_map); + addr = xen_start_info->mfn_list; + /* We roundup to the PMD, which means that if anybody at this stage is + * using the __ka address of xen_start_info or xen_start_info->shared_info + * they are in going to crash. Fortunatly we have already revectored + * in xen_setup_kernel_pagetable and in xen_setup_shared_info. */ + size = roundup(size, PMD_SIZE); + xen_cleanhighmap(addr, addr + size); + + size = PAGE_ALIGN(xen_start_info->nr_pages * sizeof(unsigned long)); + memblock_free(__pa(xen_start_info->mfn_list), size); + /* And revector! Bye bye old array */ + xen_start_info->mfn_list = new_mfn_list; + + /* At this stage, cleanup_highmap has already cleaned __ka space + * from _brk_limit way up to the max_pfn_mapped (which is the end of + * the ramdisk). We continue on, erasing PMD entries that point to page + * tables - do note that they are accessible at this stage via __va. + * For good measure we also round up to the PMD - which means that if + * anybody is using __ka address to the initial boot-stack - and try + * to use it - they are going to crash. The xen_start_info has been + * taken care of already in xen_setup_kernel_pagetable. */ + addr = xen_start_info->pt_base; + size = roundup(xen_start_info->nr_pt_frames * PAGE_SIZE, PMD_SIZE); + + xen_cleanhighmap(addr, addr + size); + xen_start_info->pt_base = (unsigned long)__va(__pa(xen_start_info->pt_base)); +#ifdef DEBUG + /* This is superflous and is not neccessary, but you know what + * lets do it. The MODULES_VADDR -> MODULES_END should be clear of + * anything at this stage. */ + xen_cleanhighmap(MODULES_VADDR, roundup(MODULES_VADDR, PUD_SIZE) - 1); +#endif +} +#endif + +static void __init xen_pagetable_init(void) { + paging_init(); xen_setup_shared_info(); +#ifdef CONFIG_X86_64 + xen_pagetable_p2m_copy(); +#endif xen_post_allocator_init(); } - static void xen_write_cr2(unsigned long cr2) { - percpu_read(xen_vcpu)->arch.cr2 = cr2; + this_cpu_read(xen_vcpu)->arch.cr2 = cr2; } static unsigned long xen_read_cr2(void) { - return percpu_read(xen_vcpu)->arch.cr2; + return this_cpu_read(xen_vcpu)->arch.cr2; } unsigned long xen_read_cr2_direct(void) { - return percpu_read(xen_vcpu_info.arch.cr2); + return this_cpu_read(xen_vcpu_info.arch.cr2); } +void xen_flush_tlb_all(void) +{ + struct mmuext_op *op; + struct multicall_space mcs; + + trace_xen_mmu_flush_tlb_all(0); + + preempt_disable(); + + mcs = xen_mc_entry(sizeof(*op)); + + op = mcs.args; + op->cmd = MMUEXT_TLB_FLUSH_ALL; + MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); + + xen_mc_issue(PARAVIRT_LAZY_MMU); + + preempt_enable(); +} static void xen_flush_tlb(void) { struct mmuext_op *op; @@ -1239,7 +1338,8 @@ static void xen_flush_tlb_single(unsigned long addr) } static void xen_flush_tlb_others(const struct cpumask *cpus, - struct mm_struct *mm, unsigned long va) + struct mm_struct *mm, unsigned long start, + unsigned long end) { struct { struct mmuext_op op; @@ -1251,7 +1351,7 @@ static void xen_flush_tlb_others(const struct cpumask *cpus, } *args; struct multicall_space mcs; - trace_xen_mmu_flush_tlb_others(cpus, mm, va); + trace_xen_mmu_flush_tlb_others(cpus, mm, start, end); if (cpumask_empty(cpus)) return; /* nothing to do */ @@ -1264,11 +1364,10 @@ static void xen_flush_tlb_others(const struct cpumask *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_TLB_FLUSH_MULTI; + if (end != TLB_FLUSH_ALL && (end - start) <= PAGE_SIZE) { args->op.cmd = MMUEXT_INVLPG_MULTI; - args->op.arg1.linear_addr = va; + args->op.arg1.linear_addr = start; } MULTI_mmuext_op(mcs.mc, &args->op, 1, NULL, DOMID_SELF); @@ -1278,12 +1377,12 @@ static void xen_flush_tlb_others(const struct cpumask *cpus, static unsigned long xen_read_cr3(void) { - return percpu_read(xen_cr3); + return this_cpu_read(xen_cr3); } static void set_current_cr3(void *v) { - percpu_write(xen_current_cr3, (unsigned long)v); + this_cpu_write(xen_current_cr3, (unsigned long)v); } static void __xen_write_cr3(bool kernel, unsigned long cr3) @@ -1306,14 +1405,13 @@ static void __xen_write_cr3(bool kernel, unsigned long cr3) xen_extend_mmuext_op(&op); if (kernel) { - percpu_write(xen_cr3, cr3); + this_cpu_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()); @@ -1322,7 +1420,7 @@ static void xen_write_cr3(unsigned long cr3) /* Update while interrupts are disabled, so its atomic with respect to ipis */ - percpu_write(xen_cr3, cr3); + this_cpu_write(xen_cr3, cr3); __xen_write_cr3(true, cr3); @@ -1339,6 +1437,43 @@ static void xen_write_cr3(unsigned long cr3) xen_mc_issue(PARAVIRT_LAZY_CPU); /* interrupts restored */ } +#ifdef CONFIG_X86_64 +/* + * At the start of the day - when Xen launches a guest, it has already + * built pagetables for the guest. We diligently look over them + * in xen_setup_kernel_pagetable and graft as appropiate them in the + * init_level4_pgt and its friends. Then when we are happy we load + * the new init_level4_pgt - and continue on. + * + * The generic code starts (start_kernel) and 'init_mem_mapping' sets + * up the rest of the pagetables. When it has completed it loads the cr3. + * N.B. that baremetal would start at 'start_kernel' (and the early + * #PF handler would create bootstrap pagetables) - so we are running + * with the same assumptions as what to do when write_cr3 is executed + * at this point. + * + * Since there are no user-page tables at all, we have two variants + * of xen_write_cr3 - the early bootup (this one), and the late one + * (xen_write_cr3). The reason we have to do that is that in 64-bit + * the Linux kernel and user-space are both in ring 3 while the + * hypervisor is in ring 0. + */ +static void __init xen_write_cr3_init(unsigned long cr3) +{ + BUG_ON(preemptible()); + + xen_mc_batch(); /* disables interrupts */ + + /* Update while interrupts are disabled, so its atomic with + respect to ipis */ + this_cpu_write(xen_cr3, cr3); + + __xen_write_cr3(true, cr3); + + xen_mc_issue(PARAVIRT_LAZY_CPU); /* interrupts restored */ +} +#endif + static int xen_pgd_alloc(struct mm_struct *mm) { pgd_t *pgd = mm->pgd; @@ -1359,7 +1494,7 @@ static int xen_pgd_alloc(struct mm_struct *mm) page->private = (unsigned long)user_pgd; if (user_pgd != NULL) { - user_pgd[pgd_index(VSYSCALL_START)] = + user_pgd[pgd_index(VSYSCALL_ADDR)] = __pgd(__pa(level3_user_vsyscall) | _PAGE_TABLE); ret = 0; } @@ -1394,30 +1529,32 @@ static pte_t __init mask_rw_pte(pte_t *ptep, pte_t pte) #else /* CONFIG_X86_64 */ static pte_t __init mask_rw_pte(pte_t *ptep, pte_t pte) { - unsigned long pfn = pte_pfn(pte); - - /* - * If the new pfn is within the range of the newly allocated - * kernel pagetable, and it isn't being mapped into an - * early_ioremap fixmap slot as a freshly allocated page, make sure - * it is RO. - */ - if (((!is_early_ioremap_ptep(ptep) && - pfn >= pgt_buf_start && pfn < pgt_buf_top)) || - (is_early_ioremap_ptep(ptep) && pfn != (pgt_buf_end - 1))) - pte = pte_wrprotect(pte); - return pte; } #endif /* CONFIG_X86_64 */ -/* Init-time set_pte while constructing initial pagetables, which - doesn't allow RO pagetable pages to be remapped RW */ +/* + * Init-time set_pte while constructing initial pagetables, which + * doesn't allow RO page table pages to be remapped RW. + * + * If there is no MFN for this PFN then this page is initially + * ballooned out so clear the PTE (as in decrease_reservation() in + * drivers/xen/balloon.c). + * + * Many of these PTE updates are done on unpinned and writable pages + * and doing a hypercall for these is unnecessary and expensive. At + * this point it is not possible to tell if a page is pinned or not, + * so always write the PTE directly and rely on Xen trapping and + * emulating any updates as necessary. + */ static void __init xen_set_pte_init(pte_t *ptep, pte_t pte) { - pte = mask_rw_pte(ptep, pte); + if (pte_mfn(pte) != INVALID_P2M_ENTRY) + pte = mask_rw_pte(ptep, pte); + else + pte = __pte_ma(0); - xen_set_pte(ptep, pte); + native_set_pte(ptep, pte); } static void pin_pagetable_pfn(unsigned cmd, unsigned long pfn) @@ -1504,7 +1641,7 @@ static inline void xen_alloc_ptpage(struct mm_struct *mm, unsigned long pfn, __set_pfn_prot(pfn, PAGE_KERNEL_RO); - if (level == PT_PTE && USE_SPLIT_PTLOCKS) + if (level == PT_PTE && USE_SPLIT_PTE_PTLOCKS) __pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE, pfn); xen_mc_issue(PARAVIRT_LAZY_MMU); @@ -1538,7 +1675,7 @@ static inline void xen_release_ptpage(unsigned long pfn, unsigned level) if (!PageHighMem(page)) { xen_mc_batch(); - if (level == PT_PTE && USE_SPLIT_PTLOCKS) + if (level == PT_PTE && USE_SPLIT_PTE_PTLOCKS) __pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, pfn); __set_pfn_prot(pfn, PAGE_KERNEL); @@ -1615,15 +1752,23 @@ static void *m2v(phys_addr_t maddr) } /* Set the page permissions on an identity-mapped pages */ -static void set_page_prot(void *addr, pgprot_t prot) +static void set_page_prot_flags(void *addr, pgprot_t prot, unsigned long flags) { unsigned long pfn = __pa(addr) >> PAGE_SHIFT; pte_t pte = pfn_pte(pfn, prot); - if (HYPERVISOR_update_va_mapping((unsigned long)addr, pte, 0)) + /* For PVH no need to set R/O or R/W to pin them or unpin them. */ + if (xen_feature(XENFEAT_auto_translated_physmap)) + return; + + if (HYPERVISOR_update_va_mapping((unsigned long)addr, pte, flags)) BUG(); } - +static void set_page_prot(void *addr, pgprot_t prot) +{ + return set_page_prot_flags(addr, prot, UVMF_NONE); +} +#ifdef CONFIG_X86_32 static void __init xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn) { unsigned pmdidx, pteidx; @@ -1674,7 +1819,7 @@ static void __init xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn) set_page_prot(pmd, PAGE_KERNEL_RO); } - +#endif void __init xen_setup_machphys_mapping(void) { struct xen_machphys_mapping mapping; @@ -1702,7 +1847,20 @@ static void convert_pfn_mfn(void *v) for (i = 0; i < PTRS_PER_PTE; i++) pte[i] = xen_make_pte(pte[i].pte); } - +static void __init check_pt_base(unsigned long *pt_base, unsigned long *pt_end, + unsigned long addr) +{ + if (*pt_base == PFN_DOWN(__pa(addr))) { + set_page_prot_flags((void *)addr, PAGE_KERNEL, UVMF_INVLPG); + clear_page((void *)addr); + (*pt_base)++; + } + if (*pt_end == PFN_DOWN(__pa(addr))) { + set_page_prot_flags((void *)addr, PAGE_KERNEL, UVMF_INVLPG); + clear_page((void *)addr); + (*pt_end)--; + } +} /* * Set up the initial kernel pagetable. * @@ -1713,12 +1871,15 @@ static void convert_pfn_mfn(void *v) * 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. + * NOTE: for PVH, the page tables are native. */ -pgd_t * __init xen_setup_kernel_pagetable(pgd_t *pgd, - unsigned long max_pfn) +void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn) { pud_t *l3; pmd_t *l2; + unsigned long addr[3]; + unsigned long pt_base, pt_end; + unsigned i; /* max_pfn_mapped is the last pfn mapped in the initial memory * mappings. Considering that on Xen after the kernel mappings we @@ -1726,58 +1887,88 @@ pgd_t * __init xen_setup_kernel_pagetable(pgd_t *pgd, * set max_pfn_mapped to the last real pfn mapped. */ max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->mfn_list)); + pt_base = PFN_DOWN(__pa(xen_start_info->pt_base)); + pt_end = pt_base + xen_start_info->nr_pt_frames; + /* 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); - + if (!xen_feature(XENFEAT_auto_translated_physmap)) { + /* Pre-constructed entries are in pfn, so convert to mfn */ + /* L4[272] -> level3_ident_pgt + * L4[511] -> level3_kernel_pgt */ + convert_pfn_mfn(init_level4_pgt); + + /* L3_i[0] -> level2_ident_pgt */ + convert_pfn_mfn(level3_ident_pgt); + /* L3_k[510] -> level2_kernel_pgt + * L3_i[511] -> level2_fixmap_pgt */ + convert_pfn_mfn(level3_kernel_pgt); + } + /* We get [511][511] and have Xen's version of level2_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); - + addr[0] = (unsigned long)pgd; + addr[1] = (unsigned long)l3; + addr[2] = (unsigned long)l2; + /* Graft it onto L4[272][0]. Note that we creating an aliasing problem: + * Both L4[272][0] and L4[511][511] have entries that point to the same + * L2 (PMD) tables. Meaning that if you modify it in __va space + * it will be also modified in the __ka space! (But if you just + * modify the PMD table to point to other PTE's or none, then you + * are OK - which is what cleanup_highmap does) */ + copy_page(level2_ident_pgt, l2); + /* Graft it onto L4[511][511] */ + copy_page(level2_kernel_pgt, l2); + + /* Get [511][510] and graft that in level2_fixmap_pgt */ 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); + copy_page(level2_fixmap_pgt, l2); + /* Note that we don't do anything with level1_fixmap_pgt which + * we don't need. */ + if (!xen_feature(XENFEAT_auto_translated_physmap)) { + /* 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_ident_pgt, 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))); - /* 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. + /* + * 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(init_level4_pgt)); + xen_mc_issue(PARAVIRT_LAZY_CPU); + } else + native_write_cr3(__pa(init_level4_pgt)); + + /* We can't that easily rip out L3 and L2, as the Xen pagetables are + * set out this way: [L4], [L1], [L2], [L3], [L1], [L1] ... for + * the initial domain. For guests using the toolstack, they are in: + * [L4], [L3], [L2], [L1], [L1], order .. So for dom0 we can only + * rip out the [L4] (pgd), but for guests we shave off three pages. */ - xen_mc_batch(); - __xen_write_cr3(true, __pa(pgd)); - xen_mc_issue(PARAVIRT_LAZY_CPU); - - memblock_reserve(__pa(xen_start_info->pt_base), - xen_start_info->nr_pt_frames * PAGE_SIZE); + for (i = 0; i < ARRAY_SIZE(addr); i++) + check_pt_base(&pt_base, &pt_end, addr[i]); - return pgd; + /* Our (by three pages) smaller Xen pagetable that we are using */ + memblock_reserve(PFN_PHYS(pt_base), (pt_end - pt_base) * PAGE_SIZE); + /* Revector the xen_start_info */ + xen_start_info = (struct start_info *)__va(__pa(xen_start_info)); } #else /* !CONFIG_X86_64 */ static RESERVE_BRK_ARRAY(pmd_t, initial_kernel_pmd, PTRS_PER_PMD); @@ -1802,8 +1993,7 @@ static void __init xen_write_cr3_init(unsigned long cr3) */ swapper_kernel_pmd = extend_brk(sizeof(pmd_t) * PTRS_PER_PMD, PAGE_SIZE); - memcpy(swapper_kernel_pmd, initial_kernel_pmd, - sizeof(pmd_t) * PTRS_PER_PMD); + copy_page(swapper_kernel_pmd, initial_kernel_pmd); swapper_pg_dir[KERNEL_PGD_BOUNDARY] = __pgd(__pa(swapper_kernel_pmd) | _PAGE_PRESENT); set_page_prot(swapper_kernel_pmd, PAGE_KERNEL_RO); @@ -1820,8 +2010,7 @@ static void __init xen_write_cr3_init(unsigned long cr3) pv_mmu_ops.write_cr3 = &xen_write_cr3; } -pgd_t * __init xen_setup_kernel_pagetable(pgd_t *pgd, - unsigned long max_pfn) +void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn) { pmd_t *kernel_pmd; @@ -1833,11 +2022,11 @@ pgd_t * __init xen_setup_kernel_pagetable(pgd_t *pgd, 512*1024); kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd); - memcpy(initial_kernel_pmd, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD); + copy_page(initial_kernel_pmd, kernel_pmd); xen_map_identity_early(initial_kernel_pmd, max_pfn); - memcpy(initial_page_table, pgd, sizeof(pgd_t) * PTRS_PER_PGD); + copy_page(initial_page_table, pgd); initial_page_table[KERNEL_PGD_BOUNDARY] = __pgd(__pa(initial_kernel_pmd) | _PAGE_PRESENT); @@ -1853,8 +2042,6 @@ pgd_t * __init xen_setup_kernel_pagetable(pgd_t *pgd, memblock_reserve(__pa(xen_start_info->pt_base), xen_start_info->nr_pt_frames * PAGE_SIZE); - - return initial_page_table; } #endif /* CONFIG_X86_64 */ @@ -1868,18 +2055,14 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot) switch (idx) { case FIX_BTMAP_END ... FIX_BTMAP_BEGIN: -#ifdef CONFIG_X86_F00F_BUG - case FIX_F00F_IDT: -#endif + case FIX_RO_IDT: #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: - case VVAR_PAGE: + case VSYSCALL_PAGE: #endif case FIX_TEXT_POKE0: case FIX_TEXT_POKE1: @@ -1920,39 +2103,18 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot) #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) || - idx == VVAR_PAGE) { + if (idx == VSYSCALL_PAGE) { unsigned long vaddr = __fix_to_virt(idx); set_pte_vaddr_pud(level3_user_vsyscall, vaddr, pte); } #endif } -void __init xen_ident_map_ISA(void) +static void __init xen_post_allocator_init(void) { - unsigned long pa; - - /* - * If we're dom0, then linear map the ISA machine addresses into - * the kernel's address space. - */ - if (!xen_initial_domain()) + if (xen_feature(XENFEAT_auto_translated_physmap)) return; - xen_raw_printk("Xen: setup ISA identity maps\n"); - - for (pa = ISA_START_ADDRESS; pa < ISA_END_ADDRESS; pa += PAGE_SIZE) { - pte_t pte = mfn_pte(PFN_DOWN(pa), PAGE_KERNEL_IO); - - if (HYPERVISOR_update_va_mapping(PAGE_OFFSET + pa, pte, 0)) - BUG(); - } - - xen_flush_tlb(); -} - -static void __init 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; @@ -1972,6 +2134,7 @@ static void __init xen_post_allocator_init(void) #endif #ifdef CONFIG_X86_64 + pv_mmu_ops.write_cr3 = &xen_write_cr3; SetPagePinned(virt_to_page(level3_user_vsyscall)); #endif xen_mark_init_mm_pinned(); @@ -1990,11 +2153,7 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = { .write_cr2 = xen_write_cr2, .read_cr3 = xen_read_cr3, -#ifdef CONFIG_X86_32 .write_cr3 = xen_write_cr3_init, -#else - .write_cr3 = xen_write_cr3, -#endif .flush_tlb_user = xen_flush_tlb, .flush_tlb_kernel = xen_flush_tlb, @@ -2051,6 +2210,7 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = { .lazy_mode = { .enter = paravirt_enter_lazy_mmu, .leave = xen_leave_lazy_mmu, + .flush = paravirt_flush_lazy_mmu, }, .set_fixmap = xen_set_fixmap, @@ -2058,9 +2218,16 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = { void __init xen_init_mmu_ops(void) { - x86_init.mapping.pagetable_reserve = xen_mapping_pagetable_reserve; - x86_init.paging.pagetable_setup_start = xen_pagetable_setup_start; - x86_init.paging.pagetable_setup_done = xen_pagetable_setup_done; + x86_init.paging.pagetable_init = xen_pagetable_init; + + /* Optimization - we can use the HVM one but it has no idea which + * VCPUs are descheduled - which means that it will needlessly IPI + * them. Xen knows so let it do the job. + */ + if (xen_feature(XENFEAT_auto_translated_physmap)) { + pv_mmu_ops.flush_tlb_others = xen_flush_tlb_others; + return; + } pv_mmu_ops = xen_mmu_ops; memset(dummy_mapping, 0xff, PAGE_SIZE); @@ -2182,12 +2349,14 @@ static int xen_exchange_memory(unsigned long extents_in, unsigned int order_in, return success; } -int xen_create_contiguous_region(unsigned long vstart, unsigned int order, - unsigned int address_bits) +int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order, + unsigned int address_bits, + dma_addr_t *dma_handle) { unsigned long *in_frames = discontig_frames, out_frame; unsigned long flags; int success; + unsigned long vstart = (unsigned long)phys_to_virt(pstart); /* * Currently an auto-translated guest will not perform I/O, nor will @@ -2222,15 +2391,17 @@ int xen_create_contiguous_region(unsigned long vstart, unsigned int order, spin_unlock_irqrestore(&xen_reservation_lock, flags); + *dma_handle = virt_to_machine(vstart).maddr; return success ? 0 : -ENOMEM; } EXPORT_SYMBOL_GPL(xen_create_contiguous_region); -void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order) +void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order) { unsigned long *out_frames = discontig_frames, in_frame; unsigned long flags; int success; + unsigned long vstart; if (xen_feature(XENFEAT_auto_translated_physmap)) return; @@ -2238,6 +2409,7 @@ void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order) if (unlikely(order > MAX_CONTIG_ORDER)) return; + vstart = (unsigned long)phys_to_virt(pstart); memset((void *) vstart, 0, PAGE_SIZE << order); spin_lock_irqsave(&xen_reservation_lock, flags); @@ -2263,6 +2435,43 @@ void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order) EXPORT_SYMBOL_GPL(xen_destroy_contiguous_region); #ifdef CONFIG_XEN_PVHVM +#ifdef CONFIG_PROC_VMCORE +/* + * This function is used in two contexts: + * - the kdump kernel has to check whether a pfn of the crashed kernel + * was a ballooned page. vmcore is using this function to decide + * whether to access a pfn of the crashed kernel. + * - the kexec kernel has to check whether a pfn was ballooned by the + * previous kernel. If the pfn is ballooned, handle it properly. + * Returns 0 if the pfn is not backed by a RAM page, the caller may + * handle the pfn special in this case. + */ +static int xen_oldmem_pfn_is_ram(unsigned long pfn) +{ + struct xen_hvm_get_mem_type a = { + .domid = DOMID_SELF, + .pfn = pfn, + }; + int ram; + + if (HYPERVISOR_hvm_op(HVMOP_get_mem_type, &a)) + return -ENXIO; + + switch (a.mem_type) { + case HVMMEM_mmio_dm: + ram = 0; + break; + case HVMMEM_ram_rw: + case HVMMEM_ram_ro: + default: + ram = 1; + break; + } + + return ram; +} +#endif + static void xen_hvm_exit_mmap(struct mm_struct *mm) { struct xen_hvm_pagetable_dying a; @@ -2293,6 +2502,98 @@ void __init xen_hvm_init_mmu_ops(void) { if (is_pagetable_dying_supported()) pv_mmu_ops.exit_mmap = xen_hvm_exit_mmap; +#ifdef CONFIG_PROC_VMCORE + register_oldmem_pfn_is_ram(&xen_oldmem_pfn_is_ram); +#endif +} +#endif + +#ifdef CONFIG_XEN_PVH +/* + * Map foreign gfn (fgfn), to local pfn (lpfn). This for the user + * space creating new guest on pvh dom0 and needing to map domU pages. + */ +static int xlate_add_to_p2m(unsigned long lpfn, unsigned long fgfn, + unsigned int domid) +{ + int rc, err = 0; + xen_pfn_t gpfn = lpfn; + xen_ulong_t idx = fgfn; + + struct xen_add_to_physmap_range xatp = { + .domid = DOMID_SELF, + .foreign_domid = domid, + .size = 1, + .space = XENMAPSPACE_gmfn_foreign, + }; + set_xen_guest_handle(xatp.idxs, &idx); + set_xen_guest_handle(xatp.gpfns, &gpfn); + set_xen_guest_handle(xatp.errs, &err); + + rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp); + if (rc < 0) + return rc; + return err; +} + +static int xlate_remove_from_p2m(unsigned long spfn, int count) +{ + struct xen_remove_from_physmap xrp; + int i, rc; + + for (i = 0; i < count; i++) { + xrp.domid = DOMID_SELF; + xrp.gpfn = spfn+i; + rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp); + if (rc) + break; + } + return rc; +} + +struct xlate_remap_data { + unsigned long fgfn; /* foreign domain's gfn */ + pgprot_t prot; + domid_t domid; + int index; + struct page **pages; +}; + +static int xlate_map_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr, + void *data) +{ + int rc; + struct xlate_remap_data *remap = data; + unsigned long pfn = page_to_pfn(remap->pages[remap->index++]); + pte_t pteval = pte_mkspecial(pfn_pte(pfn, remap->prot)); + + rc = xlate_add_to_p2m(pfn, remap->fgfn, remap->domid); + if (rc) + return rc; + native_set_pte(ptep, pteval); + + return 0; +} + +static int xlate_remap_gfn_range(struct vm_area_struct *vma, + unsigned long addr, unsigned long mfn, + int nr, pgprot_t prot, unsigned domid, + struct page **pages) +{ + int err; + struct xlate_remap_data pvhdata; + + BUG_ON(!pages); + + pvhdata.fgfn = mfn; + pvhdata.prot = prot; + pvhdata.domid = domid; + pvhdata.index = 0; + pvhdata.pages = pages; + err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT, + xlate_map_pte_fn, &pvhdata); + flush_tlb_all(); + return err; } #endif @@ -2308,7 +2609,7 @@ static int remap_area_mfn_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr, void *data) { struct remap_data *rmd = data; - pte_t pte = pte_mkspecial(pfn_pte(rmd->mfn++, rmd->prot)); + pte_t pte = pte_mkspecial(mfn_pte(rmd->mfn++, rmd->prot)); rmd->mmu_update->ptr = virt_to_machine(ptep).maddr; rmd->mmu_update->val = pte_val_ma(pte); @@ -2319,8 +2620,10 @@ static int remap_area_mfn_pte_fn(pte_t *ptep, pgtable_t token, int xen_remap_domain_mfn_range(struct vm_area_struct *vma, unsigned long addr, - unsigned long mfn, int nr, - pgprot_t prot, unsigned domid) + xen_pfn_t mfn, int nr, + pgprot_t prot, unsigned domid, + struct page **pages) + { struct remap_data rmd; struct mmu_update mmu_update[REMAP_BATCH_SIZE]; @@ -2328,10 +2631,17 @@ int xen_remap_domain_mfn_range(struct vm_area_struct *vma, unsigned long range; int err = 0; - prot = __pgprot(pgprot_val(prot) | _PAGE_IOMAP); + BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO))); - BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_RESERVED | VM_IO)) == - (VM_PFNMAP | VM_RESERVED | VM_IO))); + if (xen_feature(XENFEAT_auto_translated_physmap)) { +#ifdef CONFIG_XEN_PVH + /* We need to update the local page tables and the xen HAP */ + return xlate_remap_gfn_range(vma, addr, mfn, nr, prot, + domid, pages); +#else + return -EINVAL; +#endif + } rmd.mfn = mfn; rmd.prot = prot; @@ -2346,8 +2656,8 @@ int xen_remap_domain_mfn_range(struct vm_area_struct *vma, if (err) goto out; - err = -EFAULT; - if (HYPERVISOR_mmu_update(mmu_update, batch, NULL, domid) < 0) + err = HYPERVISOR_mmu_update(mmu_update, batch, NULL, domid); + if (err < 0) goto out; nr -= batch; @@ -2357,8 +2667,38 @@ int xen_remap_domain_mfn_range(struct vm_area_struct *vma, err = 0; out: - flush_tlb_all(); + xen_flush_tlb_all(); return err; } EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range); + +/* Returns: 0 success */ +int xen_unmap_domain_mfn_range(struct vm_area_struct *vma, + int numpgs, struct page **pages) +{ + if (!pages || !xen_feature(XENFEAT_auto_translated_physmap)) + return 0; + +#ifdef CONFIG_XEN_PVH + while (numpgs--) { + /* + * The mmu has already cleaned up the process mmu + * resources at this point (lookup_address will return + * NULL). + */ + unsigned long pfn = page_to_pfn(pages[numpgs]); + + xlate_remove_from_p2m(pfn, 1); + } + /* + * We don't need to flush tlbs because as part of + * xlate_remove_from_p2m, the hypervisor will do tlb flushes + * after removing the p2m entries from the EPT/NPT + */ + return 0; +#else + return -EINVAL; +#endif +} +EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range); |