Merge tag 'riscv-for-linus-5.11-mw0' of git://git.kernel.org/pub/scm/linux/kernel...

[linux-2.6-block.git] / arch / riscv / mm / pageattr.c

diff --git a/arch/riscv/mm/pageattr.c b/arch/riscv/mm/pageattr.c
index c64ec224fd0cdbb0984f1f136875f5ec8ed8f2b3..5e49e4b4a4cccc08df7282af5aabb193fb377daf 100644 (file)
--- a/arch/riscv/mm/pageattr.c
+++ b/arch/riscv/mm/pageattr.c
@@ -190,6 +190,7 @@ int set_direct_map_default_noflush(struct page *page)
        return ret;
 }
 
+#ifdef CONFIG_DEBUG_PAGEALLOC
 void __kernel_map_pages(struct page *page, int numpages, int enable)
 {
        if (!debug_pagealloc_enabled())
@@ -202,3 +203,33 @@ void __kernel_map_pages(struct page *page, int numpages, int enable)
                __set_memory((unsigned long)page_address(page), numpages,
                             __pgprot(0), __pgprot(_PAGE_PRESENT));
 }
+#endif
+
+bool kernel_page_present(struct page *page)
+{
+       unsigned long addr = (unsigned long)page_address(page);
+       pgd_t *pgd;
+       pud_t *pud;
+       p4d_t *p4d;
+       pmd_t *pmd;
+       pte_t *pte;
+
+       pgd = pgd_offset_k(addr);
+       if (!pgd_present(*pgd))
+               return false;
+
+       p4d = p4d_offset(pgd, addr);
+       if (!p4d_present(*p4d))
+               return false;
+
+       pud = pud_offset(p4d, addr);
+       if (!pud_present(*pud))
+               return false;
+
+       pmd = pmd_offset(pud, addr);
+       if (!pmd_present(*pmd))
+               return false;
+
+       pte = pte_offset_kernel(pmd, addr);
+       return pte_present(*pte);
+}