diff options
Diffstat (limited to 'arch/x86/xen/mmu_pv.c')
-rw-r--r-- | arch/x86/xen/mmu_pv.c | 258 |
1 files changed, 217 insertions, 41 deletions
diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c index aae88fec9941..0d7b3ae4960b 100644 --- a/arch/x86/xen/mmu_pv.c +++ b/arch/x86/xen/mmu_pv.c @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: GPL-2.0 + /* * Xen mmu operations * @@ -67,6 +69,7 @@ #include <asm/init.h> #include <asm/pat.h> #include <asm/smp.h> +#include <asm/tlb.h> #include <asm/xen/hypercall.h> #include <asm/xen/hypervisor.h> @@ -98,6 +101,12 @@ static pud_t level3_user_vsyscall[PTRS_PER_PUD] __page_aligned_bss; #endif /* CONFIG_X86_64 */ /* + * Protects atomic reservation decrease/increase against concurrent increases. + * Also protects non-atomic updates of current_pages and balloon lists. + */ +static DEFINE_SPINLOCK(xen_reservation_lock); + +/* * Note about cr3 (pagetable base) values: * * xen_cr3 contains the current logical cr3 value; it contains the @@ -116,6 +125,8 @@ DEFINE_PER_CPU(unsigned long, xen_current_cr3); /* actual vcpu cr3 */ static phys_addr_t xen_pt_base, xen_pt_size __initdata; +static DEFINE_STATIC_KEY_FALSE(xen_struct_pages_ready); + /* * Just beyond the highest usermode address. STACK_TOP_MAX has a * redzone above it, so round it up to a PGD boundary. @@ -155,11 +166,18 @@ void make_lowmem_page_readwrite(void *vaddr) } +/* + * During early boot all page table pages are pinned, but we do not have struct + * pages, so return true until struct pages are ready. + */ static bool xen_page_pinned(void *ptr) { - struct page *page = virt_to_page(ptr); + if (static_branch_likely(&xen_struct_pages_ready)) { + struct page *page = virt_to_page(ptr); - return PagePinned(page); + return PagePinned(page); + } + return true; } static void xen_extend_mmu_update(const struct mmu_update *update) @@ -425,14 +443,13 @@ static void xen_set_pud(pud_t *ptr, pud_t val) static void xen_set_pte_atomic(pte_t *ptep, pte_t pte) { trace_xen_mmu_set_pte_atomic(ptep, pte); - set_64bit((u64 *)ptep, native_pte_val(pte)); + __xen_set_pte(ptep, pte); } static void xen_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { trace_xen_mmu_pte_clear(mm, addr, ptep); - if (!xen_batched_set_pte(ptep, native_make_pte(0))) - native_pte_clear(mm, addr, ptep); + __xen_set_pte(ptep, native_make_pte(0)); } static void xen_pmd_clear(pmd_t *pmdp) @@ -538,6 +555,22 @@ static void xen_set_p4d(p4d_t *ptr, p4d_t val) xen_mc_issue(PARAVIRT_LAZY_MMU); } + +#if CONFIG_PGTABLE_LEVELS >= 5 +__visible p4dval_t xen_p4d_val(p4d_t p4d) +{ + return pte_mfn_to_pfn(p4d.p4d); +} +PV_CALLEE_SAVE_REGS_THUNK(xen_p4d_val); + +__visible p4d_t xen_make_p4d(p4dval_t p4d) +{ + p4d = pte_pfn_to_mfn(p4d); + + return native_make_p4d(p4d); +} +PV_CALLEE_SAVE_REGS_THUNK(xen_make_p4d); +#endif /* CONFIG_PGTABLE_LEVELS >= 5 */ #endif /* CONFIG_X86_64 */ static int xen_pmd_walk(struct mm_struct *mm, pmd_t *pmd, @@ -820,11 +853,6 @@ void xen_mm_pin_all(void) spin_unlock(&pgd_lock); } -/* - * The init_mm pagetable is really pinned as soon as its created, but - * that's before we have page structures to store the bits. So do all - * the book-keeping now. - */ static int __init xen_mark_pinned(struct mm_struct *mm, struct page *page, enum pt_level level) { @@ -832,8 +860,18 @@ static int __init xen_mark_pinned(struct mm_struct *mm, struct page *page, return 0; } -static void __init xen_mark_init_mm_pinned(void) +/* + * The init_mm pagetable is really pinned as soon as its created, but + * that's before we have page structures to store the bits. So do all + * the book-keeping now once struct pages for allocated pages are + * initialized. This happens only after memblock_free_all() is called. + */ +static void __init xen_after_bootmem(void) { + static_branch_enable(&xen_struct_pages_ready); +#ifdef CONFIG_X86_64 + SetPagePinned(virt_to_page(level3_user_vsyscall)); +#endif xen_pgd_walk(&init_mm, xen_mark_pinned, FIXADDR_TOP); } @@ -1200,8 +1238,7 @@ static void __init xen_pagetable_p2m_free(void) * 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. + * we have already revectored in xen_setup_kernel_pagetable. */ size = roundup(size, PMD_SIZE); @@ -1262,8 +1299,7 @@ static void __init xen_pagetable_init(void) /* Remap memory freed due to conflicts with E820 map */ xen_remap_memory(); - - xen_setup_shared_info(); + xen_setup_mfn_list_list(); } static void xen_write_cr2(unsigned long cr2) { @@ -1280,13 +1316,11 @@ unsigned long xen_read_cr2_direct(void) return this_cpu_read(xen_vcpu_info.arch.cr2); } -static void xen_flush_tlb(void) +static noinline void xen_flush_tlb(void) { struct mmuext_op *op; struct multicall_space mcs; - trace_xen_mmu_flush_tlb(0); - preempt_disable(); mcs = xen_mc_entry(sizeof(*op)); @@ -1543,7 +1577,7 @@ static void __init xen_set_pte_init(pte_t *ptep, pte_t pte) pte = __pte_ma(((pte_val_ma(*ptep) & _PAGE_RW) | ~_PAGE_RW) & pte_val_ma(pte)); #endif - native_set_pte(ptep, pte); + __xen_set_pte(ptep, pte); } /* Early in boot, while setting up the initial pagetable, assume @@ -1607,14 +1641,15 @@ static inline void __set_pfn_prot(unsigned long pfn, pgprot_t prot) static inline void xen_alloc_ptpage(struct mm_struct *mm, unsigned long pfn, unsigned level) { - bool pinned = PagePinned(virt_to_page(mm->pgd)); + bool pinned = xen_page_pinned(mm->pgd); trace_xen_mmu_alloc_ptpage(mm, pfn, level, pinned); if (pinned) { struct page *page = pfn_to_page(pfn); - SetPagePinned(page); + if (static_branch_likely(&xen_struct_pages_ready)) + SetPagePinned(page); if (!PageHighMem(page)) { xen_mc_batch(); @@ -1880,7 +1915,7 @@ void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn) /* L3_k[511] -> level2_fixmap_pgt */ convert_pfn_mfn(level3_kernel_pgt); - /* L3_k[511][506] -> level1_fixmap_pgt */ + /* L3_k[511][508-FIXMAP_PMD_NUM ... 507] -> level1_fixmap_pgt */ convert_pfn_mfn(level2_fixmap_pgt); /* We get [511][511] and have Xen's version of level2_kernel_pgt */ @@ -1925,7 +1960,11 @@ void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn) 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); - set_page_prot(level1_fixmap_pgt, PAGE_KERNEL_RO); + + for (i = 0; i < FIXMAP_PMD_NUM; i++) { + set_page_prot(level1_fixmap_pgt + i * PTRS_PER_PTE, + PAGE_KERNEL_RO); + } /* Pin down new L4 */ pin_pagetable_pfn(MMUEXT_PIN_L4_TABLE, @@ -2033,7 +2072,6 @@ void __init xen_relocate_p2m(void) pud_t *pud; pgd_t *pgd; unsigned long *new_p2m; - int save_pud; size = PAGE_ALIGN(xen_start_info->nr_pages * sizeof(unsigned long)); n_pte = roundup(size, PAGE_SIZE) >> PAGE_SHIFT; @@ -2063,7 +2101,6 @@ void __init xen_relocate_p2m(void) pgd = __va(read_cr3_pa()); new_p2m = (unsigned long *)(2 * PGDIR_SIZE); - save_pud = n_pud; for (idx_pud = 0; idx_pud < n_pud; idx_pud++) { pud = early_memremap(pud_phys, PAGE_SIZE); clear_page(pud); @@ -2144,6 +2181,8 @@ void __init xen_relocate_p2m(void) #else /* !CONFIG_X86_64 */ static RESERVE_BRK_ARRAY(pmd_t, initial_kernel_pmd, PTRS_PER_PMD); static RESERVE_BRK_ARRAY(pmd_t, swapper_kernel_pmd, PTRS_PER_PMD); +RESERVE_BRK(fixup_kernel_pmd, PAGE_SIZE); +RESERVE_BRK(fixup_kernel_pte, PAGE_SIZE); static void __init xen_write_cr3_init(unsigned long cr3) { @@ -2178,7 +2217,7 @@ static void __init xen_write_cr3_init(unsigned long cr3) set_page_prot(initial_page_table, PAGE_KERNEL); set_page_prot(initial_kernel_pmd, PAGE_KERNEL); - pv_mmu_ops.write_cr3 = &xen_write_cr3; + pv_ops.mmu.write_cr3 = &xen_write_cr3; } /* @@ -2327,30 +2366,28 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot) 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; + pv_ops.mmu.set_pte = xen_set_pte; + pv_ops.mmu.set_pmd = xen_set_pmd; + pv_ops.mmu.set_pud = xen_set_pud; #ifdef CONFIG_X86_64 - pv_mmu_ops.set_p4d = xen_set_p4d; + pv_ops.mmu.set_p4d = xen_set_p4d; #endif /* This will work as long as patching hasn't happened yet (which it hasn't) */ - pv_mmu_ops.alloc_pte = xen_alloc_pte; - pv_mmu_ops.alloc_pmd = xen_alloc_pmd; - pv_mmu_ops.release_pte = xen_release_pte; - pv_mmu_ops.release_pmd = xen_release_pmd; + pv_ops.mmu.alloc_pte = xen_alloc_pte; + pv_ops.mmu.alloc_pmd = xen_alloc_pmd; + pv_ops.mmu.release_pte = xen_release_pte; + pv_ops.mmu.release_pmd = xen_release_pmd; #ifdef CONFIG_X86_64 - pv_mmu_ops.alloc_pud = xen_alloc_pud; - pv_mmu_ops.release_pud = xen_release_pud; + pv_ops.mmu.alloc_pud = xen_alloc_pud; + pv_ops.mmu.release_pud = xen_release_pud; #endif - pv_mmu_ops.make_pte = PV_CALLEE_SAVE(xen_make_pte); + pv_ops.mmu.make_pte = PV_CALLEE_SAVE(xen_make_pte); #ifdef CONFIG_X86_64 - pv_mmu_ops.write_cr3 = &xen_write_cr3; - SetPagePinned(virt_to_page(level3_user_vsyscall)); + pv_ops.mmu.write_cr3 = &xen_write_cr3; #endif - xen_mark_init_mm_pinned(); } static void xen_leave_lazy_mmu(void) @@ -2372,6 +2409,7 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = { .flush_tlb_kernel = xen_flush_tlb, .flush_tlb_one_user = xen_flush_tlb_one_user, .flush_tlb_others = xen_flush_tlb_others, + .tlb_remove_table = tlb_remove_table, .pgd_alloc = xen_pgd_alloc, .pgd_free = xen_pgd_free, @@ -2411,6 +2449,11 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = { .alloc_pud = xen_alloc_pmd_init, .release_pud = xen_release_pmd_init, + +#if CONFIG_PGTABLE_LEVELS >= 5 + .p4d_val = PV_CALLEE_SAVE(xen_p4d_val), + .make_p4d = PV_CALLEE_SAVE(xen_make_p4d), +#endif #endif /* CONFIG_X86_64 */ .activate_mm = xen_activate_mm, @@ -2429,8 +2472,9 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = { void __init xen_init_mmu_ops(void) { x86_init.paging.pagetable_init = xen_pagetable_init; + x86_init.hyper.init_after_bootmem = xen_after_bootmem; - pv_mmu_ops = xen_mmu_ops; + pv_ops.mmu = xen_mmu_ops; memset(dummy_mapping, 0xff, PAGE_SIZE); } @@ -2630,6 +2674,138 @@ void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order) } EXPORT_SYMBOL_GPL(xen_destroy_contiguous_region); +static noinline void xen_flush_tlb_all(void) +{ + struct mmuext_op *op; + struct multicall_space mcs; + + preempt_disable(); + + mcs = xen_mc_entry(sizeof(*op)); + + op = mcs.args; + op->cmd = MMUEXT_TLB_FLUSH_ALL; + MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); + + xen_mc_issue(PARAVIRT_LAZY_MMU); + + preempt_enable(); +} + +#define REMAP_BATCH_SIZE 16 + +struct remap_data { + xen_pfn_t *pfn; + bool contiguous; + bool no_translate; + pgprot_t prot; + struct mmu_update *mmu_update; +}; + +static int remap_area_pfn_pte_fn(pte_t *ptep, pgtable_t token, + unsigned long addr, void *data) +{ + struct remap_data *rmd = data; + pte_t pte = pte_mkspecial(mfn_pte(*rmd->pfn, rmd->prot)); + + /* + * If we have a contiguous range, just update the pfn itself, + * else update pointer to be "next pfn". + */ + if (rmd->contiguous) + (*rmd->pfn)++; + else + rmd->pfn++; + + rmd->mmu_update->ptr = virt_to_machine(ptep).maddr; + rmd->mmu_update->ptr |= rmd->no_translate ? + MMU_PT_UPDATE_NO_TRANSLATE : + MMU_NORMAL_PT_UPDATE; + rmd->mmu_update->val = pte_val_ma(pte); + rmd->mmu_update++; + + return 0; +} + +int xen_remap_pfn(struct vm_area_struct *vma, unsigned long addr, + xen_pfn_t *pfn, int nr, int *err_ptr, pgprot_t prot, + unsigned int domid, bool no_translate, struct page **pages) +{ + int err = 0; + struct remap_data rmd; + struct mmu_update mmu_update[REMAP_BATCH_SIZE]; + unsigned long range; + int mapped = 0; + + BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO))); + + rmd.pfn = pfn; + rmd.prot = prot; + /* + * We use the err_ptr to indicate if there we are doing a contiguous + * mapping or a discontigious mapping. + */ + rmd.contiguous = !err_ptr; + rmd.no_translate = no_translate; + + while (nr) { + int index = 0; + int done = 0; + int batch = min(REMAP_BATCH_SIZE, nr); + int batch_left = batch; + + range = (unsigned long)batch << PAGE_SHIFT; + + rmd.mmu_update = mmu_update; + err = apply_to_page_range(vma->vm_mm, addr, range, + remap_area_pfn_pte_fn, &rmd); + if (err) + goto out; + + /* + * We record the error for each page that gives an error, but + * continue mapping until the whole set is done + */ + do { + int i; + + err = HYPERVISOR_mmu_update(&mmu_update[index], + batch_left, &done, domid); + + /* + * @err_ptr may be the same buffer as @gfn, so + * only clear it after each chunk of @gfn is + * used. + */ + if (err_ptr) { + for (i = index; i < index + done; i++) + err_ptr[i] = 0; + } + if (err < 0) { + if (!err_ptr) + goto out; + err_ptr[i] = err; + done++; /* Skip failed frame. */ + } else + mapped += done; + batch_left -= done; + index += done; + } while (batch_left); + + nr -= batch; + addr += range; + if (err_ptr) + err_ptr += batch; + cond_resched(); + } +out: + + xen_flush_tlb_all(); + + return err < 0 ? err : mapped; +} +EXPORT_SYMBOL_GPL(xen_remap_pfn); + #ifdef CONFIG_KEXEC_CORE phys_addr_t paddr_vmcoreinfo_note(void) { |