[RFC PATCH 07/18] arm64: add support of memory protection for NUMA replicas

[Nikita Panov]

Acked-by: Artem Kuzin <artem.kuzin@xxxxxxxxxx>
Acked-by: Alexander Grubnikov <alexander.grubnikov@xxxxxxxxxx>
Acked-by: Ilya Hanov <ilya.hanov@xxxxxxxxxxxxxxxxxxx>
Acked-by: Denis Darvish <darvish.denis@xxxxxxxxxx>
Signed-off-by: Nikita Panov <panov.nikita@xxxxxxxxxx>
---
 arch/arm64/mm/pageattr.c | 72 ++++++++++++++++++++++++++++++++++++++--
 1 file changed, 70 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
index bbe98ac9ad8c..50a76385b184 100644
--- a/arch/arm64/mm/pageattr.c
+++ b/arch/arm64/mm/pageattr.c
@@ -9,6 +9,7 @@
 #include <linux/sched.h>
 #include <linux/vmalloc.h>
 #include <linux/pagewalk.h>
+#include <linux/numa_kernel_replication.h>
 
 #include <asm/cacheflush.h>
 #include <asm/pgtable-prot.h>
@@ -102,7 +103,7 @@ bool can_set_direct_map(void)
 		arm64_kfence_can_set_direct_map() || is_realm_world();
 }
 
-static int update_range_prot(unsigned long start, unsigned long size,
+static int update_range_prot_pgd(pgd_t *pgtable, unsigned long start, unsigned long size,
 			     pgprot_t set_mask, pgprot_t clear_mask)
 {
 	struct page_change_data data;
@@ -123,12 +124,19 @@ static int update_range_prot(unsigned long start, unsigned long size,
 	 * must be eliminated by splitting the mapping.
 	 */
 	ret = walk_kernel_page_table_range_lockless(start, start + size,
-						    &pageattr_ops, NULL, &data);
+						    &pageattr_ops, pgtable, &data);
 	lazy_mmu_mode_disable();
 
 	return ret;
 }
 
+static int update_range_prot(unsigned long start, unsigned long size,
+			     pgprot_t set_mask, pgprot_t clear_mask)
+{
+	return update_range_prot_pgd(NULL, start, size, set_mask, clear_mask);
+}
+
+
 static int __change_memory_common(unsigned long start, unsigned long size,
 				  pgprot_t set_mask, pgprot_t clear_mask)
 {
@@ -147,6 +155,22 @@ static int __change_memory_common(unsigned long start, unsigned long size,
 	return ret;
 }
 
+#ifdef CONFIG_KERNEL_REPLICATION
+static int __change_memory_common_replicas(unsigned long start, unsigned long size,
+					pgprot_t set_mask, pgprot_t clear_mask)
+{
+	int nid;
+	int ret;
+
+	for_each_memory_node(nid) {
+		ret |= update_range_prot_pgd(per_node_pgd(&init_mm, nid), start, size, set_mask, clear_mask);
+	}
+
+	flush_tlb_kernel_range(start, start + size);
+	return ret;
+}
+#endif /* CONFIG_KERNEL_REPLICATION */
+
 static int change_memory_common(unsigned long addr, int numpages,
 				pgprot_t set_mask, pgprot_t clear_mask)
 {
@@ -211,6 +235,20 @@ static int change_memory_common(unsigned long addr, int numpages,
 	return __change_memory_common(start, size, set_mask, clear_mask);
 }
 
+#ifdef CONFIG_KERNEL_REPLICATION
+static int numa_change_memory_common(unsigned long addr, int numpages,
+				pgprot_t set_mask, pgprot_t clear_mask)
+{
+	int ret;
+
+	ret = change_memory_common(addr, numpages, set_mask, clear_mask);
+	if (ret)
+		return ret;
+
+	return __change_memory_common_replicas(addr, numpages * PAGE_SIZE, set_mask, clear_mask);
+}
+#endif /* CONFIG_KERNEL_REPLICATION */
+
 int set_memory_ro(unsigned long addr, int numpages)
 {
 	return change_memory_common(addr, numpages,
@@ -239,6 +277,36 @@ int set_memory_x(unsigned long addr, int numpages)
 					__pgprot(PTE_PXN));
 }
 
+#ifdef CONFIG_KERNEL_REPLICATION
+int numa_set_memory_x(unsigned long addr, int numpages)
+{
+	return numa_change_memory_common(addr, numpages,
+					__pgprot(PTE_MAYBE_GP),
+					__pgprot(PTE_PXN));
+}
+
+int numa_set_memory_nx(unsigned long addr, int numpages)
+{
+	return numa_change_memory_common(addr, numpages,
+					__pgprot(PTE_PXN),
+					__pgprot(PTE_MAYBE_GP));
+}
+
+int numa_set_memory_ro(unsigned long addr, int numpages)
+{
+	return numa_change_memory_common(addr, numpages,
+					__pgprot(PTE_RDONLY),
+					__pgprot(PTE_WRITE));
+}
+
+int numa_set_memory_rw(unsigned long addr, int numpages)
+{
+	return numa_change_memory_common(addr, numpages,
+					__pgprot(PTE_WRITE),
+					__pgprot(PTE_RDONLY));
+}
+#endif /*CONFIG_KERNEL_REPLICATION*/
+
 int set_memory_valid(unsigned long addr, int numpages, int enable)
 {
 	if (enable)
-- 
2.34.1