ARM: Add page table and page defines needed by KVM

KVM uses the stage-2 page tables and the Hyp page table format,
so we define the fields and page protection flags needed by KVM.

The nomenclature is this:
 - page_hyp:        PL2 code/data mappings
 - page_hyp_device: PL2 device mappings (vgic access)
 - page_s2:         Stage-2 code/data page mappings
 - page_s2_device:  Stage-2 device mappings (vgic access)

Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Christoffer Dall <c.dall@virtualopensystems.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 9f0610243bd6..1f51d712b55a 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -57,6 +57,9 @@ static unsigned int cachepolicy __initdata = CPOLICY_WRITEBACK;
 static unsigned int ecc_mask __initdata = 0;
 pgprot_t pgprot_user;
 pgprot_t pgprot_kernel;
+pgprot_t pgprot_hyp_device;
+pgprot_t pgprot_s2;
+pgprot_t pgprot_s2_device;
 
 EXPORT_SYMBOL(pgprot_user);
 EXPORT_SYMBOL(pgprot_kernel);
@@ -66,34 +69,46 @@ struct cachepolicy {
         unsigned int    cr_mask;
         pmdval_t        pmd;
         pteval_t        pte;
+        pteval_t        pte_s2;
 };
 
+#ifdef CONFIG_ARM_LPAE
+#define s2_policy(policy)       policy
+#else
+#define s2_policy(policy)       0
+#endif
+
 static struct cachepolicy cache_policies[] __initdata = {
         {
                 .policy         = "uncached",
                 .cr_mask        = CR_W|CR_C,
                 .pmd            = PMD_SECT_UNCACHED,
                 .pte            = L_PTE_MT_UNCACHED,
+                .pte_s2         = s2_policy(L_PTE_S2_MT_UNCACHED),
         }, {
                 .policy         = "buffered",
                 .cr_mask        = CR_C,
                 .pmd            = PMD_SECT_BUFFERED,
                 .pte            = L_PTE_MT_BUFFERABLE,
+                .pte_s2         = s2_policy(L_PTE_S2_MT_UNCACHED),
         }, {
                 .policy         = "writethrough",
                 .cr_mask        = 0,
                 .pmd            = PMD_SECT_WT,
                 .pte            = L_PTE_MT_WRITETHROUGH,
+                .pte_s2         = s2_policy(L_PTE_S2_MT_WRITETHROUGH),
         }, {
                 .policy         = "writeback",
                 .cr_mask        = 0,
                 .pmd            = PMD_SECT_WB,
                 .pte            = L_PTE_MT_WRITEBACK,
+                .pte_s2         = s2_policy(L_PTE_S2_MT_WRITEBACK),
         }, {
                 .policy         = "writealloc",
                 .cr_mask        = 0,
                 .pmd            = PMD_SECT_WBWA,
                 .pte            = L_PTE_MT_WRITEALLOC,
+                .pte_s2         = s2_policy(L_PTE_S2_MT_WRITEBACK),
         }
 };
 
@@ -310,6 +325,7 @@ static void __init build_mem_type_table(void)
         struct cachepolicy *cp;
         unsigned int cr = get_cr();
         pteval_t user_pgprot, kern_pgprot, vecs_pgprot;
+        pteval_t hyp_device_pgprot, s2_pgprot, s2_device_pgprot;
         int cpu_arch = cpu_architecture();
         int i;
 
@@ -421,6 +437,8 @@ static void __init build_mem_type_table(void)
          */
         cp = &cache_policies[cachepolicy];
         vecs_pgprot = kern_pgprot = user_pgprot = cp->pte;
+        s2_pgprot = cp->pte_s2;
+        hyp_device_pgprot = s2_device_pgprot = mem_types[MT_DEVICE].prot_pte;
 
         /*
          * ARMv6 and above have extended page tables.
@@ -444,6 +462,7 @@ static void __init build_mem_type_table(void)
                         user_pgprot |= L_PTE_SHARED;
                         kern_pgprot |= L_PTE_SHARED;
                         vecs_pgprot |= L_PTE_SHARED;
+                        s2_pgprot |= L_PTE_SHARED;
                         mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_S;
                         mem_types[MT_DEVICE_WC].prot_pte |= L_PTE_SHARED;
                         mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_S;
@@ -498,6 +517,9 @@ static void __init build_mem_type_table(void)
         pgprot_user   = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | user_pgprot);
         pgprot_kernel = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG |
                                  L_PTE_DIRTY | kern_pgprot);
+        pgprot_s2  = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | s2_pgprot);
+        pgprot_s2_device  = __pgprot(s2_device_pgprot);
+        pgprot_hyp_device  = __pgprot(hyp_device_pgprot);
 
         mem_types[MT_LOW_VECTORS].prot_l1 |= ecc_mask;
         mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask;