arm64: Add support for ARCH_SUPPORTS_DEBUG_PAGEALLOC

[cascardo/linux.git] / arch / arm64 / mm / mmu.c

diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index ef0d66c..a6f28e5 100644 (file)
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -149,6 +149,26 @@ static void split_pud(pud_t *old_pud, pmd_t *pmd)
        } while (pmd++, i++, i < PTRS_PER_PMD);
 }
 
+#ifdef CONFIG_DEBUG_PAGEALLOC
+static bool block_mappings_allowed(phys_addr_t (*pgtable_alloc)(void))
+{
+
+       /*
+        * If debug_page_alloc is enabled we must map the linear map
+        * using pages. However, other mappings created by
+        * create_mapping_noalloc must use sections in some cases. Allow
+        * sections to be used in those cases, where no pgtable_alloc
+        * function is provided.
+        */
+       return !pgtable_alloc || !debug_pagealloc_enabled();
+}
+#else
+static bool block_mappings_allowed(phys_addr_t (*pgtable_alloc)(void))
+{
+       return true;
+}
+#endif
+
 static void alloc_init_pmd(pud_t *pud, unsigned long addr, unsigned long end,
                                  phys_addr_t phys, pgprot_t prot,
                                  phys_addr_t (*pgtable_alloc)(void))
@@ -181,7 +201,8 @@ static void alloc_init_pmd(pud_t *pud, unsigned long addr, unsigned long end,
        do {
                next = pmd_addr_end(addr, end);
                /* try section mapping first */
-               if (((addr | next | phys) & ~SECTION_MASK) == 0) {
+               if (((addr | next | phys) & ~SECTION_MASK) == 0 &&
+                     block_mappings_allowed(pgtable_alloc)) {
                        pmd_t old_pmd =*pmd;
                        set_pmd(pmd, __pmd(phys |
                                           pgprot_val(mk_sect_prot(prot))));
@@ -241,7 +262,8 @@ static void alloc_init_pud(pgd_t *pgd, unsigned long addr, unsigned long end,
                /*
                 * For 4K granule only, attempt to put down a 1GB block
                 */
-               if (use_1G_block(addr, next, phys)) {
+               if (use_1G_block(addr, next, phys) &&
+                   block_mappings_allowed(pgtable_alloc)) {
                        pud_t old_pud = *pud;
                        set_pud(pud, __pud(phys |
                                           pgprot_val(mk_sect_prot(prot))));