1 files changed, 248 insertions, 0 deletions
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 10ed4643269..4decdb61801 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -15,3 +15,251 @@
  * along with this program; if not, write to the Free Software
  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  */
+
+#include <linux/mman.h>
+#include <linux/kvm_host.h>
+#include <linux/io.h>
+#include <asm/idmap.h>
+#include <asm/pgalloc.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_mmu.h>
+#include <asm/mach/map.h>
+
+extern char  __hyp_idmap_text_start[], __hyp_idmap_text_end[];
+
+static DEFINE_MUTEX(kvm_hyp_pgd_mutex);
+
+static void kvm_set_pte(pte_t *pte, pte_t new_pte)
+{
+	pte_val(*pte) = new_pte;
+	/*
+	 * flush_pmd_entry just takes a void pointer and cleans the necessary
+	 * cache entries, so we can reuse the function for ptes.
+	 */
+	flush_pmd_entry(pte);
+}
+
+static void free_ptes(pmd_t *pmd, unsigned long addr)
+{
+	pte_t *pte;
+	unsigned int i;
+
+	for (i = 0; i < PTRS_PER_PMD; i++, addr += PMD_SIZE) {
+		if (!pmd_none(*pmd) && pmd_table(*pmd)) {
+			pte = pte_offset_kernel(pmd, addr);
+			pte_free_kernel(NULL, pte);
+		}
+		pmd++;
+	}
+}
+
+/**
+ * free_hyp_pmds - free a Hyp-mode level-2 tables and child level-3 tables
+ *
+ * Assumes this is a page table used strictly in Hyp-mode and therefore contains
+ * only mappings in the kernel memory area, which is above PAGE_OFFSET.
+ */
+void free_hyp_pmds(void)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	unsigned long addr;
+
+	mutex_lock(&kvm_hyp_pgd_mutex);
+	for (addr = PAGE_OFFSET; addr != 0; addr += PGDIR_SIZE) {
+		pgd = hyp_pgd + pgd_index(addr);
+		pud = pud_offset(pgd, addr);
+
+		if (pud_none(*pud))
+			continue;
+		BUG_ON(pud_bad(*pud));
+
+		pmd = pmd_offset(pud, addr);
+		free_ptes(pmd, addr);
+		pmd_free(NULL, pmd);
+		pud_clear(pud);
+	}
+	mutex_unlock(&kvm_hyp_pgd_mutex);
+}
+
+static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start,
+				    unsigned long end)
+{
+	pte_t *pte;
+	unsigned long addr;
+	struct page *page;
+
+	for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) {
+		pte = pte_offset_kernel(pmd, addr);
+		BUG_ON(!virt_addr_valid(addr));
+		page = virt_to_page(addr);
+		kvm_set_pte(pte, mk_pte(page, PAGE_HYP));
+	}
+}
+
+static void create_hyp_io_pte_mappings(pmd_t *pmd, unsigned long start,
+				       unsigned long end,
+				       unsigned long *pfn_base)
+{
+	pte_t *pte;
+	unsigned long addr;
+
+	for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) {
+		pte = pte_offset_kernel(pmd, addr);
+		BUG_ON(pfn_valid(*pfn_base));
+		kvm_set_pte(pte, pfn_pte(*pfn_base, PAGE_HYP_DEVICE));
+		(*pfn_base)++;
+	}
+}
+
+static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
+				   unsigned long end, unsigned long *pfn_base)
+{
+	pmd_t *pmd;
+	pte_t *pte;
+	unsigned long addr, next;
+
+	for (addr = start; addr < end; addr = next) {
+		pmd = pmd_offset(pud, addr);
+
+		BUG_ON(pmd_sect(*pmd));
+
+		if (pmd_none(*pmd)) {
+			pte = pte_alloc_one_kernel(NULL, addr);
+			if (!pte) {
+				kvm_err("Cannot allocate Hyp pte\n");
+				return -ENOMEM;
+			}
+			pmd_populate_kernel(NULL, pmd, pte);
+		}
+
+		next = pmd_addr_end(addr, end);
+
+		/*
+		 * If pfn_base is NULL, we map kernel pages into HYP with the
+		 * virtual address. Otherwise, this is considered an I/O
+		 * mapping and we map the physical region starting at
+		 * *pfn_base to [start, end[.
+		 */
+		if (!pfn_base)
+			create_hyp_pte_mappings(pmd, addr, next);
+		else
+			create_hyp_io_pte_mappings(pmd, addr, next, pfn_base);
+	}
+
+	return 0;
+}
+
+static int __create_hyp_mappings(void *from, void *to, unsigned long *pfn_base)
+{
+	unsigned long start = (unsigned long)from;
+	unsigned long end = (unsigned long)to;
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	unsigned long addr, next;
+	int err = 0;
+
+	BUG_ON(start > end);
+	if (start < PAGE_OFFSET)
+		return -EINVAL;
+
+	mutex_lock(&kvm_hyp_pgd_mutex);
+	for (addr = start; addr < end; addr = next) {
+		pgd = hyp_pgd + pgd_index(addr);
+		pud = pud_offset(pgd, addr);
+
+		if (pud_none_or_clear_bad(pud)) {
+			pmd = pmd_alloc_one(NULL, addr);
+			if (!pmd) {
+				kvm_err("Cannot allocate Hyp pmd\n");
+				err = -ENOMEM;
+				goto out;
+			}
+			pud_populate(NULL, pud, pmd);
+		}
+
+		next = pgd_addr_end(addr, end);
+		err = create_hyp_pmd_mappings(pud, addr, next, pfn_base);
+		if (err)
+			goto out;
+	}
+out:
+	mutex_unlock(&kvm_hyp_pgd_mutex);
+	return err;
+}
+
+/**
+ * create_hyp_mappings - map a kernel virtual address range in Hyp mode
+ * @from:	The virtual kernel start address of the range
+ * @to:		The virtual kernel end address of the range (exclusive)
+ *
+ * The same virtual address as the kernel virtual address is also used in
+ * Hyp-mode mapping to the same underlying physical pages.
+ *
+ * Note: Wrapping around zero in the "to" address is not supported.
+ */
+int create_hyp_mappings(void *from, void *to)
+{
+	return __create_hyp_mappings(from, to, NULL);
+}
+
+/**
+ * create_hyp_io_mappings - map a physical IO range in Hyp mode
+ * @from:	The virtual HYP start address of the range
+ * @to:		The virtual HYP end address of the range (exclusive)
+ * @addr:	The physical start address which gets mapped
+ */
+int create_hyp_io_mappings(void *from, void *to, phys_addr_t addr)
+{
+	unsigned long pfn = __phys_to_pfn(addr);
+	return __create_hyp_mappings(from, to, &pfn);
+}
+
+int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+	return -EINVAL;
+}
+
+phys_addr_t kvm_mmu_get_httbr(void)
+{
+	VM_BUG_ON(!virt_addr_valid(hyp_pgd));
+	return virt_to_phys(hyp_pgd);
+}
+
+int kvm_mmu_init(void)
+{
+	return hyp_pgd ? 0 : -ENOMEM;
+}
+
+/**
+ * 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);
+		clean_pmd_entry(pmd);
+		pmd_free(NULL, (pmd_t *)((unsigned long)pmd & PAGE_MASK));
+	} while (pgd++, addr = next, addr < end);
+}