granicus.if.org Git - strace/blob - userfaultfd.c

   1 /*
   2  * Copyright (c) 2015 Dmitry V. Levin <ldv@altlinux.org>
   3  * Copyright (c) 2015-2017 The strace developers.
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 3. The name of the author may not be used to endorse or promote products
  15  *    derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include "defs.h"
  30 #include "print_fields.h"
  31 #include <fcntl.h>
  32
  33 #include "xlat/uffd_flags.h"
  34
  35 SYS_FUNC(userfaultfd)
  36 {
  37         printflags(uffd_flags, tcp->u_arg[0], "UFFD_???");
  38
  39         return RVAL_DECODED | RVAL_FD;
  40 }
  41
  42 #ifdef HAVE_LINUX_USERFAULTFD_H
  43 # include <linux/ioctl.h>
  44 # include <linux/userfaultfd.h>
  45
  46 # include "xlat/uffd_api_features.h"
  47 # include "xlat/uffd_api_flags.h"
  48 # include "xlat/uffd_copy_flags.h"
  49 # include "xlat/uffd_register_ioctl_flags.h"
  50 # include "xlat/uffd_register_mode_flags.h"
  51 # include "xlat/uffd_zeropage_flags.h"
  52
  53 static void
  54 tprintf_uffdio_range(const struct uffdio_range *range)
  55 {
  56         PRINT_FIELD_X("{", *range, start);
  57         PRINT_FIELD_X(", ", *range, len);
  58         tprints("}");
  59 }
  60
  61 #define PRINT_FIELD_UFFDIO_RANGE(prefix_, where_, field_)               \
  62         do {                                                            \
  63                 STRACE_PRINTF("%s%s=", (prefix_), #field_);             \
  64                 tprintf_uffdio_range(&(where_).field_);                 \
  65         } while (0)
  66
  67 int
  68 uffdio_ioctl(struct tcb *const tcp, const unsigned int code,
  69              const kernel_ulong_t arg)
  70 {
  71         switch (code) {
  72         case UFFDIO_API: {
  73                 uint64_t *entering_features;
  74                 struct uffdio_api ua;
  75
  76                 if (entering(tcp)) {
  77                         tprints(", ");
  78                         if (umove_or_printaddr(tcp, arg, &ua))
  79                                 break;
  80                         PRINT_FIELD_X("{", ua, api);
  81                         PRINT_FIELD_FLAGS(", ", ua, features, uffd_api_features,
  82                                           "UFFD_FEATURE_???");
  83                         entering_features = malloc(sizeof(*entering_features));
  84                         if (entering_features) {
  85                                 *entering_features = ua.features;
  86                                 set_tcb_priv_data(tcp, entering_features, free);
  87                         }
  88
  89                         return 0;
  90                 }
  91
  92                 if (!syserror(tcp) && !umove(tcp, arg, &ua)) {
  93                         entering_features = get_tcb_priv_data(tcp);
  94
  95                         if (!entering_features
  96                             || *entering_features != ua.features) {
  97                                 PRINT_FIELD_FLAGS(" => ", ua, features,
  98                                                   uffd_api_features,
  99                                                   "UFFD_FEATURE_???");
 100                         }
 101
 102                         PRINT_FIELD_FLAGS(", ", ua, ioctls, uffd_api_flags,
 103                                           "_UFFDIO_???");
 104                 }
 105
 106                 tprints("}");
 107
 108                 break;
 109         }
 110
 111         case UFFDIO_COPY: {
 112                 struct uffdio_copy uc;
 113
 114                 if (entering(tcp)) {
 115                         tprints(", ");
 116                         if (umove_or_printaddr(tcp, arg, &uc))
 117                                 return RVAL_IOCTL_DECODED;
 118                         PRINT_FIELD_X("{", uc, dst);
 119                         PRINT_FIELD_X(", ", uc, src);
 120                         PRINT_FIELD_X(", ", uc, len);
 121                         PRINT_FIELD_FLAGS(", ", uc, mode, uffd_copy_flags,
 122                                           "UFFDIO_COPY_???");
 123
 124                         return 0;
 125                 }
 126
 127                 if (!syserror(tcp) && !umove(tcp, arg, &uc))
 128                         PRINT_FIELD_X(", ", uc, copy);
 129
 130                 tprints("}");
 131
 132                 break;
 133         }
 134
 135         case UFFDIO_REGISTER: {
 136                 struct uffdio_register ur;
 137
 138                 if (entering(tcp)) {
 139                         tprints(", ");
 140                         if (umove_or_printaddr(tcp, arg, &ur))
 141                                 return RVAL_IOCTL_DECODED;
 142                         PRINT_FIELD_UFFDIO_RANGE("{", ur, range);
 143                         PRINT_FIELD_FLAGS(", ", ur, mode,
 144                                           uffd_register_mode_flags,
 145                                           "UFFDIO_REGISTER_MODE_???");
 146
 147                         return 0;
 148                 }
 149
 150                 if (!syserror(tcp) && !umove(tcp, arg, &ur)) {
 151                         PRINT_FIELD_FLAGS(", ", ur, ioctls,
 152                                           uffd_register_ioctl_flags,
 153                                           "UFFDIO_???");
 154                 }
 155
 156                 tprints("}");
 157
 158                 break;
 159         }
 160
 161         case UFFDIO_UNREGISTER:
 162         case UFFDIO_WAKE: {
 163                 struct uffdio_range ura;
 164
 165                 tprints(", ");
 166
 167                 if (!umove_or_printaddr(tcp, arg, &ura))
 168                         tprintf_uffdio_range(&ura);
 169
 170                 break;
 171         }
 172
 173         case UFFDIO_ZEROPAGE: {
 174                 struct uffdio_zeropage uz;
 175
 176                 if (entering(tcp)) {
 177                         tprints(", ");
 178                         if (umove_or_printaddr(tcp, arg, &uz))
 179                                 return RVAL_IOCTL_DECODED;
 180                         PRINT_FIELD_UFFDIO_RANGE("{", uz, range);
 181                         PRINT_FIELD_FLAGS(", ", uz, mode, uffd_zeropage_flags,
 182                                           "UFFDIO_ZEROPAGE_???");
 183
 184                         return 0;
 185                 }
 186
 187                 if (!syserror(tcp) && !umove(tcp, arg, &uz))
 188                         PRINT_FIELD_X(", ", uz, zeropage);
 189
 190                 tprints("}");
 191
 192                 break;
 193         }
 194
 195         default:
 196                 return RVAL_DECODED;
 197         }
 198
 199         return RVAL_IOCTL_DECODED;
 200 }
 201 #endif /* HAVE_LINUX_USERFAULTFD_H */