bsd-user/bsd-mem.h

   1 /*
   2  *  memory management system call shims and definitions
   3  *
   4  *  Copyright (c) 2013-15 Stacey D. Son
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 /*
  21  * Copyright (c) 1982, 1986, 1993
  22  *      The Regents of the University of California.  All rights reserved.
  23  *
  24  * Redistribution and use in source and binary forms, with or without
  25  * modification, are permitted provided that the following conditions
  26  * are met:
  27  * 1. Redistributions of source code must retain the above copyright
  28  *    notice, this list of conditions and the following disclaimer.
  29  * 2. Redistributions in binary form must reproduce the above copyright
  30  *    notice, this list of conditions and the following disclaimer in the
  31  *    documentation and/or other materials provided with the distribution.
  32  * 4. Neither the name of the University nor the names of its contributors
  33  *    may be used to endorse or promote products derived from this software
  34  *    without specific prior written permission.
  35  *
  36  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  37  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  38  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  39  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  40  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  41  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  42  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  43  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  44  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  45  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  46  * SUCH DAMAGE.
  47  */
  48
  49 #ifndef BSD_USER_BSD_MEM_H
  50 #define BSD_USER_BSD_MEM_H
  51
  52 #include <sys/types.h>
  53 #include <sys/ipc.h>
  54 #include <sys/mman.h>
  55 #include <sys/shm.h>
  56 #include <fcntl.h>
  57
  58 #include "qemu-bsd.h"
  59
  60 extern struct bsd_shm_regions bsd_shm_regions[];
  61 extern abi_ulong target_brk;
  62 extern abi_ulong initial_target_brk;
  63
  64 /* mmap(2) */
  65 static inline abi_long do_bsd_mmap(void *cpu_env, abi_long arg1, abi_long arg2,
  66     abi_long arg3, abi_long arg4, abi_long arg5, abi_long arg6, abi_long arg7,
  67     abi_long arg8)
  68 {
  69     if (regpairs_aligned(cpu_env) != 0) {
  70         arg6 = arg7;
  71         arg7 = arg8;
  72     }
  73     return get_errno(target_mmap(arg1, arg2, arg3,
  74                                  target_to_host_bitmask(arg4, mmap_flags_tbl),
  75                                  arg5, target_arg64(arg6, arg7)));
  76 }
  77
  78 /* munmap(2) */
  79 static inline abi_long do_bsd_munmap(abi_long arg1, abi_long arg2)
  80 {
  81     return get_errno(target_munmap(arg1, arg2));
  82 }
  83
  84 /* mprotect(2) */
  85 static inline abi_long do_bsd_mprotect(abi_long arg1, abi_long arg2,
  86         abi_long arg3)
  87 {
  88     return get_errno(target_mprotect(arg1, arg2, arg3));
  89 }
  90
  91 /* msync(2) */
  92 static inline abi_long do_bsd_msync(abi_long addr, abi_long len, abi_long flags)
  93 {
  94     if (!guest_range_valid_untagged(addr, len)) {
  95         /* It seems odd, but POSIX wants this to be ENOMEM */
  96         return -TARGET_ENOMEM;
  97     }
  98
  99     return get_errno(msync(g2h_untagged(addr), len, flags));
 100 }
 101
 102 /* mlock(2) */
 103 static inline abi_long do_bsd_mlock(abi_long arg1, abi_long arg2)
 104 {
 105     if (!guest_range_valid_untagged(arg1, arg2)) {
 106         return -TARGET_EINVAL;
 107     }
 108     return get_errno(mlock(g2h_untagged(arg1), arg2));
 109 }
 110
 111 /* munlock(2) */
 112 static inline abi_long do_bsd_munlock(abi_long arg1, abi_long arg2)
 113 {
 114     if (!guest_range_valid_untagged(arg1, arg2)) {
 115         return -TARGET_EINVAL;
 116     }
 117     return get_errno(munlock(g2h_untagged(arg1), arg2));
 118 }
 119
 120 /* mlockall(2) */
 121 static inline abi_long do_bsd_mlockall(abi_long arg1)
 122 {
 123     return get_errno(mlockall(arg1));
 124 }
 125
 126 /* munlockall(2) */
 127 static inline abi_long do_bsd_munlockall(void)
 128 {
 129     return get_errno(munlockall());
 130 }
 131
 132 /* madvise(2) */
 133 static inline abi_long do_bsd_madvise(abi_long arg1, abi_long arg2,
 134         abi_long arg3)
 135 {
 136     abi_ulong len;
 137     int ret = 0;
 138     abi_long start = arg1;
 139     abi_long len_in = arg2;
 140     abi_long advice = arg3;
 141
 142     if (start & ~TARGET_PAGE_MASK) {
 143         return -TARGET_EINVAL;
 144     }
 145     if (len_in == 0) {
 146         return 0;
 147     }
 148     len = TARGET_PAGE_ALIGN(len_in);
 149     if (len == 0 || !guest_range_valid_untagged(start, len)) {
 150         return -TARGET_EINVAL;
 151     }
 152
 153     /*
 154      * Most advice values are hints, so ignoring and returning success is ok.
 155      *
 156      * However, some advice values such as MADV_DONTNEED, are not hints and
 157      * need to be emulated.
 158      *
 159      * A straight passthrough for those may not be safe because qemu sometimes
 160      * turns private file-backed mappings into anonymous mappings.
 161      * If all guest pages have PAGE_PASSTHROUGH set, mappings have the
 162      * same semantics for the host as for the guest.
 163      *
 164      * MADV_DONTNEED is passed through, if possible.
 165      * If passthrough isn't possible, we nevertheless (wrongly!) return
 166      * success, which is broken but some userspace programs fail to work
 167      * otherwise. Completely implementing such emulation is quite complicated
 168      * though.
 169      */
 170     mmap_lock();
 171     switch (advice) {
 172     case MADV_DONTNEED:
 173         if (page_check_range(start, len, PAGE_PASSTHROUGH)) {
 174             ret = get_errno(madvise(g2h_untagged(start), len, advice));
 175             if (ret == 0) {
 176                 page_reset_target_data(start, start + len - 1);
 177             }
 178         }
 179     }
 180     mmap_unlock();
 181
 182     return ret;
 183 }
 184
 185 /* minherit(2) */
 186 static inline abi_long do_bsd_minherit(abi_long addr, abi_long len,
 187         abi_long inherit)
 188 {
 189     return get_errno(minherit(g2h_untagged(addr), len, inherit));
 190 }
 191
 192 #endif /* BSD_USER_BSD_MEM_H */