Commit 6e2c2d0f authored by Ram Pai's avatar Ram Pai Committed by Linus Torvalds
Browse files

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.

Signed-off-by: default avatarRam Pai <linuxram@us.ibm.com>
Signed-off-by: default avatarThiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: default avatarSandipan Das <sandipan@linux.ibm.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Acked-by: default avatarDave 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: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 4e06e718

tools/testing/selftests/vm/pkey-helpers.h

+6 −0
Original line number Diff line number Diff line
@@ -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"

tools/testing/selftests/vm/pkey-powerpc.h

+25 −0
Original line number Diff line number Diff line
@@ -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 */

tools/testing/selftests/vm/pkey-x86.h

+5 −0
Original line number Diff line number Diff line
@@ -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 */

tools/testing/selftests/vm/protection_keys.c

+1 −0
Original line number Diff line number Diff line
@@ -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:

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