diff options
Diffstat (limited to 'arch/arm/kvm/mmu.c')
| -rw-r--r-- | arch/arm/kvm/mmu.c | 132 |
1 files changed, 94 insertions, 38 deletions
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 7464824..4646c17 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -32,9 +32,15 @@ extern char __hyp_idmap_text_start[], __hyp_idmap_text_end[]; +static pgd_t *boot_hyp_pgd; static pgd_t *hyp_pgd; static DEFINE_MUTEX(kvm_hyp_pgd_mutex); +static void *init_bounce_page; +static unsigned long hyp_idmap_start; +static unsigned long hyp_idmap_end; +static phys_addr_t hyp_idmap_vector; + static void kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa) { kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, kvm, ipa); @@ -152,9 +158,12 @@ static void unmap_range(pgd_t *pgdp, unsigned long long start, u64 size) /** * free_hyp_pgds - free Hyp-mode page tables * - * Assumes hyp_pgd is a page table used strictly in Hyp-mode and therefore contains - * either mappings in the kernel memory area (above PAGE_OFFSET), or - * device mappings in the vmalloc range (from VMALLOC_START to VMALLOC_END). + * Assumes hyp_pgd is a page table used strictly in Hyp-mode and + * therefore contains either mappings in the kernel memory area (above + * PAGE_OFFSET), or device mappings in the vmalloc range (from + * VMALLOC_START to VMALLOC_END). + * + * boot_hyp_pgd should only map two pages for the init code. */ void free_hyp_pgds(void) { @@ -162,6 +171,12 @@ void free_hyp_pgds(void) mutex_lock(&kvm_hyp_pgd_mutex); + if (boot_hyp_pgd) { + unmap_range(boot_hyp_pgd, hyp_idmap_start, PAGE_SIZE); + unmap_range(boot_hyp_pgd, TRAMPOLINE_VA, PAGE_SIZE); + kfree(boot_hyp_pgd); + } + if (hyp_pgd) { for (addr = PAGE_OFFSET; virt_addr_valid(addr); addr += PGDIR_SIZE) unmap_range(hyp_pgd, KERN_TO_HYP(addr), PGDIR_SIZE); @@ -170,6 +185,7 @@ void free_hyp_pgds(void) kfree(hyp_pgd); } + kfree(init_bounce_page); mutex_unlock(&kvm_hyp_pgd_mutex); } @@ -185,6 +201,7 @@ static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start, pte = pte_offset_kernel(pmd, addr); kvm_set_pte(pte, pfn_pte(pfn, prot)); get_page(virt_to_page(pte)); + kvm_flush_dcache_to_poc(pte, sizeof(*pte)); pfn++; } while (addr += PAGE_SIZE, addr != end); } @@ -211,6 +228,7 @@ static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start, } pmd_populate_kernel(NULL, pmd, pte); get_page(virt_to_page(pmd)); + kvm_flush_dcache_to_poc(pmd, sizeof(*pmd)); } next = pmd_addr_end(addr, end); @@ -248,6 +266,7 @@ static int __create_hyp_mappings(pgd_t *pgdp, } pud_populate(NULL, pud, pmd); get_page(virt_to_page(pud)); + kvm_flush_dcache_to_poc(pud, sizeof(*pud)); } next = pgd_addr_end(addr, end); @@ -689,18 +708,64 @@ void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu) phys_addr_t kvm_mmu_get_httbr(void) { - VM_BUG_ON(!virt_addr_valid(hyp_pgd)); return virt_to_phys(hyp_pgd); } +phys_addr_t kvm_mmu_get_boot_httbr(void) +{ + return virt_to_phys(boot_hyp_pgd); +} + +phys_addr_t kvm_get_idmap_vector(void) +{ + return hyp_idmap_vector; +} + int kvm_mmu_init(void) { - unsigned long hyp_idmap_start = virt_to_phys(__hyp_idmap_text_start); - unsigned long hyp_idmap_end = virt_to_phys(__hyp_idmap_text_end); int err; + hyp_idmap_start = virt_to_phys(__hyp_idmap_text_start); + hyp_idmap_end = virt_to_phys(__hyp_idmap_text_end); + hyp_idmap_vector = virt_to_phys(__kvm_hyp_init); + + if ((hyp_idmap_start ^ hyp_idmap_end) & PAGE_MASK) { + /* + * Our init code is crossing a page boundary. Allocate + * a bounce page, copy the code over and use that. + */ + size_t len = __hyp_idmap_text_end - __hyp_idmap_text_start; + phys_addr_t phys_base; + + init_bounce_page = kmalloc(PAGE_SIZE, GFP_KERNEL); + if (!init_bounce_page) { + kvm_err("Couldn't allocate HYP init bounce page\n"); + err = -ENOMEM; + goto out; + } + + memcpy(init_bounce_page, __hyp_idmap_text_start, len); + /* + * Warning: the code we just copied to the bounce page + * must be flushed to the point of coherency. + * Otherwise, the data may be sitting in L2, and HYP + * mode won't be able to observe it as it runs with + * caches off at that point. + */ + kvm_flush_dcache_to_poc(init_bounce_page, len); + + phys_base = virt_to_phys(init_bounce_page); + hyp_idmap_vector += phys_base - hyp_idmap_start; + hyp_idmap_start = phys_base; + hyp_idmap_end = phys_base + len; + + kvm_info("Using HYP init bounce page @%lx\n", + (unsigned long)phys_base); + } + hyp_pgd = kzalloc(PTRS_PER_PGD * sizeof(pgd_t), GFP_KERNEL); - if (!hyp_pgd) { + boot_hyp_pgd = kzalloc(PTRS_PER_PGD * sizeof(pgd_t), GFP_KERNEL); + if (!hyp_pgd || !boot_hyp_pgd) { kvm_err("Hyp mode PGD not allocated\n"); err = -ENOMEM; goto out; @@ -718,39 +783,30 @@ int kvm_mmu_init(void) goto out; } + /* Map the very same page at the trampoline VA */ + err = __create_hyp_mappings(boot_hyp_pgd, + TRAMPOLINE_VA, TRAMPOLINE_VA + PAGE_SIZE, + __phys_to_pfn(hyp_idmap_start), + PAGE_HYP); + if (err) { + kvm_err("Failed to map trampoline @%lx into boot HYP pgd\n", + TRAMPOLINE_VA); + goto out; + } + + /* Map the same page again into the runtime page tables */ + err = __create_hyp_mappings(hyp_pgd, + TRAMPOLINE_VA, TRAMPOLINE_VA + PAGE_SIZE, + __phys_to_pfn(hyp_idmap_start), + PAGE_HYP); + if (err) { + kvm_err("Failed to map trampoline @%lx into runtime HYP pgd\n", + TRAMPOLINE_VA); + goto out; + } + return 0; out: free_hyp_pgds(); return err; } - -/** - * kvm_clear_idmap - remove all idmaps from the hyp pgd - * - * Free the underlying pmds for all pgds in range and clear the pgds (but - * don't free them) afterwards. - */ -void kvm_clear_hyp_idmap(void) -{ - unsigned long addr, end; - unsigned long next; - pgd_t *pgd = hyp_pgd; - pud_t *pud; - pmd_t *pmd; - - addr = virt_to_phys(__hyp_idmap_text_start); - end = virt_to_phys(__hyp_idmap_text_end); - - pgd += pgd_index(addr); - do { - next = pgd_addr_end(addr, end); - if (pgd_none_or_clear_bad(pgd)) - continue; - pud = pud_offset(pgd, addr); - pmd = pmd_offset(pud, addr); - - pud_clear(pud); - kvm_clean_pmd_entry(pmd); - pmd_free(NULL, (pmd_t *)((unsigned long)pmd & PAGE_MASK)); - } while (pgd++, addr = next, addr < end); -} |