selftests/vm/pkeys: introduce a sub-page allocator
authorRam Pai <linuxram@us.ibm.com>
Thu, 4 Jun 2020 23:52:39 +0000 (16:52 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 5 Jun 2020 02:06:27 +0000 (19:06 -0700)
This introduces a new allocator that allocates 4K hardware pages to back
64K linux pages.  This allocator is available only on powerpc.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/c4a82fa962ec71015b994fab1aaf83bdfd091553.1585646528.git.sandipan@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
tools/testing/selftests/vm/pkey-helpers.h
tools/testing/selftests/vm/pkey-powerpc.h
tools/testing/selftests/vm/pkey-x86.h
tools/testing/selftests/vm/protection_keys.c

index 59ccdff18214f6e96d6904a175bfc17dba3b99c8..622a85848f61b387acfd741868a528a51d95e602 100644 (file)
@@ -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(int *ptr);
 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"
index 1f82caa6293b12086ce12808a5bc20871164045e..2f7174ee90e5460062f1a5661480d09cd043ff4f 100644 (file)
@@ -107,4 +107,29 @@ void expect_fault_on_read_execonly_key(void *p1, int pkey)
 /* 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 */
index 6421b846aa169c86670eea08f0e85e45cef3556b..3be20f5d527522429a193abf4aa25797c58ee140 100644 (file)
@@ -173,4 +173,9 @@ void expect_fault_on_read_execonly_key(void *p1, int pkey)
        expected_pkey_fault(pkey);
 }
 
+void *malloc_pkey_with_mprotect_subpage(long size, int prot, u16 pkey)
+{
+       return PTR_ERR_ENOTSUP;
+}
+
 #endif /* _PKEYS_X86_H */
index 8bb4de1038743ebc8ea90e1d54da4706c67d4d55..d4952b57cc9099faaaaa85d6a15006588cab9693 100644 (file)
@@ -845,6 +845,7 @@ 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: