summaryrefslogtreecommitdiffstats
path: root/arch/parisc/include/asm/kfence.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/parisc/include/asm/kfence.h')
-rw-r--r--arch/parisc/include/asm/kfence.h44
1 files changed, 44 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/kfence.h b/arch/parisc/include/asm/kfence.h
new file mode 100644
index 0000000000..6259e5ac1f
--- /dev/null
+++ b/arch/parisc/include/asm/kfence.h
@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * PA-RISC KFENCE support.
+ *
+ * Copyright (C) 2021, Helge Deller <deller@gmx.de>
+ */
+
+#ifndef _ASM_PARISC_KFENCE_H
+#define _ASM_PARISC_KFENCE_H
+
+#include <linux/kfence.h>
+
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+
+static inline bool arch_kfence_init_pool(void)
+{
+ return true;
+}
+
+/* Protect the given page and flush TLB. */
+static inline bool kfence_protect_page(unsigned long addr, bool protect)
+{
+ pte_t *pte = virt_to_kpte(addr);
+
+ if (WARN_ON(!pte))
+ return false;
+
+ /*
+ * We need to avoid IPIs, as we may get KFENCE allocations or faults
+ * with interrupts disabled.
+ */
+
+ if (protect)
+ set_pte(pte, __pte(pte_val(*pte) & ~_PAGE_PRESENT));
+ else
+ set_pte(pte, __pte(pte_val(*pte) | _PAGE_PRESENT));
+
+ flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
+
+ return true;
+}
+
+#endif /* _ASM_PARISC_KFENCE_H */