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                 if (entering(tcp)) {
  76                         tprints(", ");
  77                         if (umove_or_printaddr(tcp, arg, &ua))
  78                                 return RVAL_DECODED | 1;
  79                         PRINT_FIELD_X("{", ua, api);
  80                         PRINT_FIELD_FLAGS(", ", ua, features, uffd_api_features,
  81                                           "UFFD_FEATURE_???");
  82                         entering_features = malloc(sizeof(*entering_features));
  83                         if (entering_features) {
  84                                 *entering_features = ua.features;
  85                                 set_tcb_priv_data(tcp, entering_features, free);
  86                         }
  87                 } else {
  88                         if (!syserror(tcp) && !umove(tcp, arg, &ua)) {
  89                                 entering_features = get_tcb_priv_data(tcp);
  90                                 if (!entering_features
  91                                     || *entering_features != ua.features) {
  92                                         PRINT_FIELD_FLAGS(" => ", ua, features,
  93                                                           uffd_api_features,
  94                                                           "UFFD_FEATURE_???");
  95                                 }
  96                                 PRINT_FIELD_FLAGS(", ", ua, ioctls,
  97                                                   uffd_api_flags,
  98                                                   "_UFFDIO_???");
  99                         }
 100                         tprints("}");
 101                 }
 102                 return 1;
 103         }
 104
 105         case UFFDIO_COPY: {
 106                 struct uffdio_copy uc;
 107                 if (entering(tcp)) {
 108                         tprints(", ");
 109                         if (umove_or_printaddr(tcp, arg, &uc))
 110                                 return RVAL_DECODED | 1;
 111                         PRINT_FIELD_X("{", uc, dst);
 112                         PRINT_FIELD_X(", ", uc, src);
 113                         PRINT_FIELD_X(", ", uc, len);
 114                         PRINT_FIELD_FLAGS(", ", uc, mode, uffd_copy_flags,
 115                                           "UFFDIO_COPY_???");
 116                 } else {
 117                         if (!syserror(tcp) && !umove(tcp, arg, &uc))
 118                                 PRINT_FIELD_X(", ", uc, copy);
 119                         tprints("}");
 120                 }
 121                 return 1;
 122         }
 123
 124         case UFFDIO_REGISTER: {
 125                 struct uffdio_register ur;
 126                 if (entering(tcp)) {
 127                         tprints(", ");
 128                         if (umove_or_printaddr(tcp, arg, &ur))
 129                                 return RVAL_DECODED | 1;
 130                         PRINT_FIELD_UFFDIO_RANGE("{", ur, range);
 131                         PRINT_FIELD_FLAGS(", ", ur, mode,
 132                                           uffd_register_mode_flags,
 133                                           "UFFDIO_REGISTER_MODE_???");
 134                 } else {
 135                         if (!syserror(tcp) && !umove(tcp, arg, &ur)) {
 136                                 PRINT_FIELD_FLAGS(", ", ur, ioctls,
 137                                                   uffd_register_ioctl_flags,
 138                                                   "UFFDIO_???");
 139                         }
 140                         tprints("}");
 141                 }
 142                 return 1;
 143         }
 144
 145         case UFFDIO_UNREGISTER:
 146         case UFFDIO_WAKE: {
 147                 struct uffdio_range ura;
 148                 tprints(", ");
 149                 if (!umove_or_printaddr(tcp, arg, &ura))
 150                         tprintf_uffdio_range(&ura);
 151                 return RVAL_DECODED | 1;
 152         }
 153
 154         case UFFDIO_ZEROPAGE: {
 155                 struct uffdio_zeropage uz;
 156                 if (entering(tcp)) {
 157                         tprints(", ");
 158                         if (umove_or_printaddr(tcp, arg, &uz))
 159                                 return RVAL_DECODED | 1;
 160                         PRINT_FIELD_UFFDIO_RANGE("{", uz, range);
 161                         PRINT_FIELD_FLAGS(", ", uz, mode, uffd_zeropage_flags,
 162                                           "UFFDIO_ZEROPAGE_???");
 163                 } else {
 164                         if (!syserror(tcp) && !umove(tcp, arg, &uz))
 165                                 PRINT_FIELD_X(", ", uz, zeropage);
 166                         tprints("}");
 167                 }
 168                 return 1;
 169         }
 170
 171         default:
 172                 return RVAL_DECODED;
 173         }
 174 }
 175 #endif /* HAVE_LINUX_USERFAULTFD_H */