From e42175f10662c47c9d759844e20dba8df8e017d8 Mon Sep 17 00:00:00 2001
From: Ram Pai <linuxram@us.ibm.com>
Date: Mon, 22 Jan 2018 10:52:14 -0800
Subject: [PATCH 27/30] selftests/vm: sub-page allocator
References: FATE#322447, bsc#1078248
Patch-mainline: submitted https://lists.ozlabs.org/pipermail/linuxppc-dev/2018-January/168234.html
introduce a new allocator that allocates 4k hardware-pages to back
64k linux-page. This allocator is only applicable on powerpc.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
tools/testing/selftests/vm/protection_keys.c | 30 ++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
index 578358733646..ae71dad42947 100644
--- a/tools/testing/selftests/vm/protection_keys.c
+++ b/tools/testing/selftests/vm/protection_keys.c
@@ -766,6 +766,35 @@ void *malloc_pkey_with_mprotect(long size, int prot, u16 pkey)
return ptr;
}
+void *malloc_pkey_with_mprotect_subpage(long size, int prot, u16 pkey)
+{
+#ifdef __powerpc64__
+ void *ptr;
+ int ret;
+
+ dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
+ size, prot, pkey);
+ pkey_assert(pkey < NR_PKEYS);
+ ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ pkey_assert(ptr != (void *)-1);
+
+ ret = syscall(__NR_subpage_prot, ptr, size, NULL);
+ if (ret) {
+ perror("subpage_perm");
+ return PTR_ERR_ENOTSUP;
+ }
+
+ ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
+ pkey_assert(!ret);
+ record_pkey_malloc(ptr, size);
+
+ dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
+ return ptr;
+#else /* __powerpc64__ */
+ return PTR_ERR_ENOTSUP;
+#endif /* __powerpc64__ */
+}
+
void *malloc_pkey_anon_huge(long size, int prot, u16 pkey)
{
int ret;
@@ -888,6 +917,7 @@ void *malloc_pkey_mmap_dax(long size, int prot, u16 pkey)
void *(*pkey_malloc[])(long size, int prot, u16 pkey) = {
malloc_pkey_with_mprotect,
+ malloc_pkey_with_mprotect_subpage,
malloc_pkey_anon_huge,
malloc_pkey_hugetlb
/* can not do direct with the pkey_mprotect() API:
--
2.13.6