(root)/
strace-6.5/
tests-m32/
ioctl_uffdio.c
       1  /*
       2   * Copyright (c) 2015-2016 Dmitry V. Levin <ldv@strace.io>
       3   * Copyright (c)      2016 Red Hat, Inc.
       4   * Copyright (c) 2016-2021 The strace developers.
       5   * All rights reserved.
       6   *
       7   * SPDX-License-Identifier: GPL-2.0-or-later
       8   */
       9  
      10  #include "tests.h"
      11  #include "scno.h"
      12  
      13  #include <inttypes.h>
      14  #include <stdint.h>
      15  #include <stdio.h>
      16  #include <string.h>
      17  #include <unistd.h>
      18  
      19  #include <sys/ioctl.h>
      20  #include <sys/mman.h>
      21  
      22  #include "kernel_fcntl.h"
      23  #include <linux/ioctl.h>
      24  #include <linux/userfaultfd.h>
      25  
      26  #include "xlat.h"
      27  #include "xlat/uffd_api_features.h"
      28  
      29  int
      30  main(void)
      31  {
      32  	int rc;
      33  	int fd = syscall(__NR_userfaultfd, O_NONBLOCK);
      34  	size_t pagesize = getpagesize();
      35  
      36  	if (fd < 0)
      37  		perror_msg_and_skip("userfaultfd");
      38  
      39  	/* ---- API ---- */
      40  	TAIL_ALLOC_OBJECT_CONST_PTR(struct uffdio_api, api_struct);
      41  
      42  	/* With a bad fd */
      43  	memset(api_struct, 0, sizeof(*api_struct));
      44  	rc = ioctl(-1, UFFDIO_API, api_struct);
      45  	printf("ioctl(-1, UFFDIO_API, {api=0, features=0}) = %d %s (%m)\n",
      46  	       rc, errno2name());
      47  	/* With a bad pointer */
      48  	rc = ioctl(fd, UFFDIO_API, NULL);
      49  	printf("ioctl(%d, UFFDIO_API, NULL) = %d %s (%m)\n",
      50  		fd, rc, errno2name());
      51  	/* Normal call */
      52  	api_struct->api = UFFD_API;
      53  	api_struct->features = 0;
      54  	rc = ioctl(fd, UFFDIO_API, api_struct);
      55  	printf("ioctl(%d, UFFDIO_API, {api=0xaa, features=0", fd);
      56  	if (api_struct->features) {
      57  		printf(" => features=");
      58  		printflags(uffd_api_features, api_struct->features,
      59  			   "UFFD_FEATURE_???");
      60  	}
      61  	printf(", ioctls=1<<_UFFDIO_REGISTER|"
      62  	       "1<<_UFFDIO_UNREGISTER|1<<_UFFDIO_API");
      63  	api_struct->ioctls &= ~(1ull<<_UFFDIO_REGISTER|
      64  				1ull<<_UFFDIO_UNREGISTER|
      65  				1ull<<_UFFDIO_API);
      66  	if (api_struct->ioctls)
      67  		printf("|%#" PRIx64, (uint64_t)api_struct->ioctls);
      68  	printf("}) = %d\n", rc);
      69  
      70  	/* For the rest of the tests we need some anonymous memory */
      71  	void *area1 = mmap(NULL, pagesize, PROT_READ|PROT_WRITE,
      72  			   MAP_PRIVATE|MAP_ANONYMOUS,
      73  			   -1, 0);
      74  	if (area1 == MAP_FAILED)
      75  		perror_msg_and_fail("mmap area1");
      76  	void *area2 = mmap(NULL, pagesize, PROT_READ|PROT_WRITE,
      77  			   MAP_PRIVATE|MAP_ANONYMOUS,
      78  			   -1, 0);
      79  	if (area2 == MAP_FAILED)
      80  		perror_msg_and_fail("mmap area2");
      81  	madvise(area2, pagesize, MADV_DONTNEED);
      82  	*(char *)area1 = 42;
      83  
      84  	/* ---- REGISTER ---- */
      85  	struct uffdio_register *register_struct =
      86  					 tail_alloc(sizeof(*register_struct));
      87  	memset(register_struct, 0, sizeof(*register_struct));
      88  
      89  	rc = ioctl(-1, UFFDIO_REGISTER, register_struct);
      90  	printf("ioctl(-1, UFFDIO_REGISTER, {range={start=0, len=0}, "
      91  	       "mode=0}) = %d %s (%m)\n", rc, errno2name());
      92  
      93  	rc = ioctl(fd, UFFDIO_REGISTER, NULL);
      94  	printf("ioctl(%d, UFFDIO_REGISTER, NULL) = %d %s (%m)\n",
      95  	       fd, rc, errno2name());
      96  
      97  	register_struct->range.start = (uint64_t)(uintptr_t)area2;
      98  	register_struct->range.len = pagesize;
      99  	register_struct->mode = UFFDIO_REGISTER_MODE_MISSING;
     100  	rc = ioctl(fd, UFFDIO_REGISTER, register_struct);
     101  	printf("ioctl(%d, UFFDIO_REGISTER, {range={start=%p, len=%#zx}, "
     102  	       "mode=UFFDIO_REGISTER_MODE_MISSING, ioctls="
     103  	       "1<<_UFFDIO_WAKE|1<<_UFFDIO_COPY|1<<_UFFDIO_ZEROPAGE",
     104  	       fd, area2, pagesize);
     105  	register_struct->ioctls &= ~(1ull<<_UFFDIO_WAKE|
     106  				    1ull<<_UFFDIO_COPY|
     107  				    1ull<<_UFFDIO_ZEROPAGE);
     108  	if (register_struct->ioctls)
     109  		printf("|%#" PRIx64, (uint64_t)register_struct->ioctls);
     110  	printf("}) = %d\n", rc);
     111  
     112  	/* With area2 registered we can now do the atomic copies onto it
     113  	 * but be careful not to access it in any other way otherwise
     114  	 * userfaultfd will cause us to stall.
     115  	 */
     116  	/* ---- COPY ---- */
     117  	TAIL_ALLOC_OBJECT_CONST_PTR(struct uffdio_copy, copy_struct);
     118  
     119  	memset(copy_struct, 0, sizeof(*copy_struct));
     120  	rc = ioctl(-1, UFFDIO_COPY, copy_struct);
     121  	printf("ioctl(-1, UFFDIO_COPY, {dst=0, src=0, len=0, mode=0"
     122  	       "}) = %d %s (%m)\n", rc, errno2name());
     123  
     124  	rc = ioctl(fd, UFFDIO_COPY, NULL);
     125  	printf("ioctl(%d, UFFDIO_COPY, NULL) = %d %s (%m)\n",
     126  	       fd, rc, errno2name());
     127  
     128  	copy_struct->dst = (uint64_t)(uintptr_t)area2;
     129  	copy_struct->src = (uint64_t)(uintptr_t)area1;
     130  	copy_struct->len = pagesize;
     131  	copy_struct->mode = UFFDIO_COPY_MODE_DONTWAKE;
     132  	rc = ioctl(fd, UFFDIO_COPY, copy_struct);
     133  	printf("ioctl(%d, UFFDIO_COPY, {dst=%p, src=%p, len=%#zx,"
     134  	       " mode=UFFDIO_COPY_MODE_DONTWAKE, copy=%#zx}) = %d\n",
     135  	       fd, area2, area1, pagesize, pagesize, rc);
     136  
     137  	copy_struct->mode = 0xdeadbeef;;
     138  	rc = ioctl(fd, UFFDIO_COPY, copy_struct);
     139  	printf("ioctl(%d, UFFDIO_COPY, {dst=%p, src=%p, len=%#zx,"
     140  	       " mode=UFFDIO_COPY_MODE_DONTWAKE|UFFDIO_COPY_MODE_WP|0xdeadbeec"
     141  	       "}) = %s\n",
     142  	       fd, area2, area1, pagesize, sprintrc(rc));
     143  
     144  	/* ---- ZEROPAGE ---- */
     145  	TAIL_ALLOC_OBJECT_CONST_PTR(struct uffdio_zeropage, zero_struct);
     146  	madvise(area2, pagesize, MADV_DONTNEED);
     147  
     148  	memset(zero_struct, 0, sizeof(*zero_struct));
     149  	rc = ioctl(-1, UFFDIO_ZEROPAGE, zero_struct);
     150  	printf("ioctl(-1, UFFDIO_ZEROPAGE, {range={start=0, len=0}, mode=0"
     151  	       "}) = %d %s (%m)\n", rc, errno2name());
     152  
     153  	rc = ioctl(fd, UFFDIO_ZEROPAGE, NULL);
     154  	printf("ioctl(%d, UFFDIO_ZEROPAGE, NULL) = %d %s (%m)\n",
     155  	       fd, rc, errno2name());
     156  
     157  	zero_struct->range.start = (uint64_t)(uintptr_t)area2;
     158  	zero_struct->range.len = pagesize;
     159  	zero_struct->mode = UFFDIO_ZEROPAGE_MODE_DONTWAKE;
     160  	rc = ioctl(fd, UFFDIO_ZEROPAGE, zero_struct);
     161  	printf("ioctl(%d, UFFDIO_ZEROPAGE, {range={start=%p, len=%#zx},"
     162  	       " mode=UFFDIO_ZEROPAGE_MODE_DONTWAKE, zeropage=%#zx}) = %d\n",
     163  	       fd, area2, pagesize, pagesize, rc);
     164  
     165  	/* ---- WAKE ---- */
     166  	TAIL_ALLOC_OBJECT_CONST_PTR(struct uffdio_range, range_struct);
     167  	memset(range_struct, 0, sizeof(*range_struct));
     168  
     169  	rc = ioctl(-1, UFFDIO_WAKE, range_struct);
     170  	printf("ioctl(-1, UFFDIO_WAKE, {start=0, len=0}) = %d %s (%m)\n",
     171  	       rc, errno2name());
     172  
     173  	rc = ioctl(fd, UFFDIO_WAKE, NULL);
     174  	printf("ioctl(%d, UFFDIO_WAKE, NULL) = %d %s (%m)\n",
     175  	       fd, rc, errno2name());
     176  
     177  	range_struct->start = (uint64_t)(uintptr_t)area2;
     178  	range_struct->len = pagesize;
     179  	rc = ioctl(fd, UFFDIO_WAKE, range_struct);
     180  	printf("ioctl(%d, UFFDIO_WAKE, {start=%p, len=%#zx}) = %d\n",
     181  	       fd, area2, pagesize, rc);
     182  
     183  	/* ---- UNREGISTER ---- */
     184  	memset(range_struct, 0, sizeof(*range_struct));
     185  
     186  	rc = ioctl(-1, UFFDIO_UNREGISTER, range_struct);
     187  	printf("ioctl(-1, UFFDIO_UNREGISTER, {start=0, len=0}) = %d %s (%m)\n",
     188  	       rc, errno2name());
     189  
     190  	rc = ioctl(fd, UFFDIO_UNREGISTER, NULL);
     191  	printf("ioctl(%d, UFFDIO_UNREGISTER, NULL) = %d %s (%m)\n",
     192  	       fd, rc, errno2name());
     193  
     194  	range_struct->start = (uint64_t)(uintptr_t)area2;
     195  	range_struct->len = pagesize;
     196  	rc = ioctl(fd, UFFDIO_UNREGISTER, range_struct);
     197  	printf("ioctl(%d, UFFDIO_UNREGISTER, {start=%p, len=%#zx}) = %d\n",
     198  	       fd, area2, pagesize, rc);
     199  	puts("+++ exited with 0 +++");
     200  	return 0;
     201  }