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 --- tools/testing/selftests/vm/protection_keys.c | 30 ++++++++++++++++++++++++++ 1 files changed, 30 insertions(+), 0 deletions(-)
diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c index 5783587..ae71dad 100644 --- a/tools/testing/selftests/vm/protection_keys.c +++ b/tools/testing/selftests/vm/protection_keys.c @@ -766,6 +766,35 @@ void free_pkey_malloc(void *ptr) 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 setup_hugetlbfs(void) 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: