From: Ram Pai <linuxram@xxxxxxxxxx> Subject: selftests/vm/pkeys: introduce a sub-page allocator This introduces a new allocator that allocates 4K hardware pages to back 64K linux pages. This allocator is available only on powerpc. Link: http://lkml.kernel.org/r/c4a82fa962ec71015b994fab1aaf83bdfd091553.1585646528.git.sandipan@xxxxxxxxxxxxx Signed-off-by: Ram Pai <linuxram@xxxxxxxxxx> Signed-off-by: Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxx> Signed-off-by: Sandipan Das <sandipan@xxxxxxxxxxxxx> Acked-by: Dave Hansen <dave.hansen@xxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxx> Cc: Florian Weimer <fweimer@xxxxxxxxxx> Cc: "Desnes A. Nunes do Rosario" <desnesn@xxxxxxxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Michal Suchanek <msuchanek@xxxxxxx> Cc: Shuah Khan <shuah@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/vm/pkey-helpers.h | 6 ++++ tools/testing/selftests/vm/pkey-powerpc.h | 25 +++++++++++++++++ tools/testing/selftests/vm/pkey-x86.h | 5 +++ tools/testing/selftests/vm/protection_keys.c | 1 4 files changed, 37 insertions(+) --- a/tools/testing/selftests/vm/pkey-helpers.h~selftests-vm-pkeys-introduce-a-sub-page-allocator +++ a/tools/testing/selftests/vm/pkey-helpers.h @@ -28,6 +28,9 @@ extern int dprint_in_signal; extern char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE]; +extern int test_nr; +extern int iteration_nr; + #ifdef __GNUC__ __attribute__((format(printf, 1, 2))) #endif @@ -78,6 +81,9 @@ __attribute__((noinline)) int read_ptr(i void expected_pkey_fault(int pkey); int sys_pkey_alloc(unsigned long flags, unsigned long init_val); int sys_pkey_free(unsigned long pkey); +int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot, + unsigned long pkey); +void record_pkey_malloc(void *ptr, long size, int prot); #if defined(__i386__) || defined(__x86_64__) /* arch */ #include "pkey-x86.h" --- a/tools/testing/selftests/vm/pkey-powerpc.h~selftests-vm-pkeys-introduce-a-sub-page-allocator +++ a/tools/testing/selftests/vm/pkey-powerpc.h @@ -107,4 +107,29 @@ void expect_fault_on_read_execonly_key(v /* 4-byte instructions * 16384 = 64K page */ #define __page_o_noops() asm(".rept 16384 ; nop; .endr") +void *malloc_pkey_with_mprotect_subpage(long size, int prot, u16 pkey) +{ + 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, prot); + + dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr); + return ptr; +} + #endif /* _PKEYS_POWERPC_H */ --- a/tools/testing/selftests/vm/pkey-x86.h~selftests-vm-pkeys-introduce-a-sub-page-allocator +++ a/tools/testing/selftests/vm/pkey-x86.h @@ -173,4 +173,9 @@ void expect_fault_on_read_execonly_key(v expected_pkey_fault(pkey); } +void *malloc_pkey_with_mprotect_subpage(long size, int prot, u16 pkey) +{ + return PTR_ERR_ENOTSUP; +} + #endif /* _PKEYS_X86_H */ --- a/tools/testing/selftests/vm/protection_keys.c~selftests-vm-pkeys-introduce-a-sub-page-allocator +++ a/tools/testing/selftests/vm/protection_keys.c @@ -845,6 +845,7 @@ void *malloc_pkey_mmap_dax(long size, in 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: _
