selftests/powerpc: Add subpage protection self test.

hugetlb_vs_thp_test

subpage_prot

tempfile

noarg:

	$(MAKE) -C ../

PROGS := hugetlb_vs_thp_test

PROGS := hugetlb_vs_thp_test subpage_prot

all: $(PROGS)

all: $(PROGS) tempfile

$(PROGS): ../harness.c

		./$$PROG; \

	done;

tempfile:

	dd if=/dev/zero of=tempfile bs=64k count=1

clean:

	rm -f $(PROGS)

	rm -f $(PROGS) tempfile

.PHONY: all run_tests clean

/*

 * Copyright IBM Corp.

 *

 * This program is free software; you can redistribute it and/or modify it

 * under the terms of version 2.1 of the GNU Lesser General Public License

 * as published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it would be useful, but

 * WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

 *

 */

#include <assert.h>

#include <errno.h>

#include <fcntl.h>

#include <signal.h>

#include <stdarg.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <sys/mman.h>

#include <sys/ptrace.h>

#include <sys/syscall.h>

#include <ucontext.h>

#include <unistd.h>

#include "utils.h"

char *file_name;

int in_test;

volatile int faulted;

volatile void *dar;

int errors;

static void segv(int signum, siginfo_t *info, void *ctxt_v)

{

	ucontext_t *ctxt = (ucontext_t *)ctxt_v;

	struct pt_regs *regs = ctxt->uc_mcontext.regs;

	if (!in_test) {

		fprintf(stderr, "Segfault outside of test !\n");

		exit(1);

	}

	faulted = 1;

	dar = (void *)regs->dar;

	regs->nip += 4;

}

static inline void do_read(const volatile void *addr)

{

	int ret;

	asm volatile("lwz %0,0(%1); twi 0,%0,0; isync;\n"

		     : "=r" (ret) : "r" (addr) : "memory");

}

static inline void do_write(const volatile void *addr)

{

	int val = 0x1234567;

	asm volatile("stw %0,0(%1); sync; \n"

		     : : "r" (val), "r" (addr) : "memory");

}

static inline void check_faulted(void *addr, long page, long subpage, int write)

{

	int want_fault = (subpage == ((page + 3) % 16));

	if (write)

		want_fault |= (subpage == ((page + 1) % 16));

	if (faulted != want_fault) {

		printf("Failed at 0x%p (p=%ld,sp=%ld,w=%d), want=%s, got=%s !\n",

		       addr, page, subpage, write,

		       want_fault ? "fault" : "pass",

		       faulted ? "fault" : "pass");

		++errors;

	}

	if (faulted) {

		if (dar != addr) {

			printf("Fault expected at 0x%p and happened at 0x%p !\n",

			       addr, dar);

		}

		faulted = 0;

		asm volatile("sync" : : : "memory");

	}

}

static int run_test(void *addr, unsigned long size)

{

	unsigned int *map;

	long i, j, pages, err;

	pages = size / 0x10000;

	map = malloc(pages * 4);

	assert(map);

	/*

	 * for each page, mark subpage i % 16 read only and subpage

	 * (i + 3) % 16 inaccessible

	 */

	for (i = 0; i < pages; i++) {

		map[i] = (0x40000000 >> (((i + 1) * 2) % 32)) |

			(0xc0000000 >> (((i + 3) * 2) % 32));

	}

	err = syscall(__NR_subpage_prot, addr, size, map);

	if (err) {

		perror("subpage_perm");

		return 1;

	}

	free(map);

	in_test = 1;

	errors = 0;

	for (i = 0; i < pages; i++) {

		for (j = 0; j < 16; j++, addr += 0x1000) {

			do_read(addr);

			check_faulted(addr, i, j, 0);

			do_write(addr);

			check_faulted(addr, i, j, 1);

		}

	}

	in_test = 0;

	if (errors) {

		printf("%d errors detected\n", errors);

		return 1;

	}

	return 0;

}

int test_anon(void)

{

	unsigned long align;

	struct sigaction act = {

		.sa_sigaction = segv,

		.sa_flags = SA_SIGINFO

	};

	void *mallocblock;

	unsigned long mallocsize;

	if (getpagesize() != 0x10000) {

		fprintf(stderr, "Kernel page size must be 64K!\n");

		return 1;

	}

	sigaction(SIGSEGV, &act, NULL);

	mallocsize = 4 * 16 * 1024 * 1024;

	FAIL_IF(posix_memalign(&mallocblock, 64 * 1024, mallocsize));

	align = (unsigned long)mallocblock;

	if (align & 0xffff)

		align = (align | 0xffff) + 1;

	mallocblock = (void *)align;

	printf("allocated malloc block of 0x%lx bytes at 0x%p\n",

	       mallocsize, mallocblock);

	printf("testing malloc block...\n");

	return run_test(mallocblock, mallocsize);

}

int test_file(void)

{

	struct sigaction act = {

		.sa_sigaction = segv,

		.sa_flags = SA_SIGINFO

	};

	void *fileblock;

	off_t filesize;

	int fd;

	fd = open(file_name, O_RDWR);

	if (fd == -1) {

		perror("failed to open file");

		return 1;

	}

	sigaction(SIGSEGV, &act, NULL);

	filesize = lseek(fd, 0, SEEK_END);

	if (filesize & 0xffff)

		filesize &= ~0xfffful;

	fileblock = mmap(NULL, filesize, PROT_READ | PROT_WRITE,

			 MAP_SHARED, fd, 0);

	if (fileblock == MAP_FAILED) {

		perror("failed to map file");

		return 1;

	}

	printf("allocated %s for 0x%lx bytes at 0x%p\n",

	       file_name, filesize, fileblock);

	printf("testing file map...\n");

	return run_test(fileblock, filesize);

}

int main(int argc, char *argv[])

{

	test_harness(test_anon, "subpage_prot_anon");

	if (argc > 1)

		file_name = argv[1];

	else

		file_name = "tempfile";

	test_harness(test_file, "subpage_prot_file");

	return 0;

}