xref: /openbmc/qemu/util/oslib-win32.c (revision ab0c7fb2)
1 /*
2  * os-win32.c
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  * Copyright (c) 2010-2016 Red Hat, Inc.
6  *
7  * QEMU library functions for win32 which are shared between QEMU and
8  * the QEMU tools.
9  *
10  * Permission is hereby granted, free of charge, to any person obtaining a copy
11  * of this software and associated documentation files (the "Software"), to deal
12  * in the Software without restriction, including without limitation the rights
13  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
14  * copies of the Software, and to permit persons to whom the Software is
15  * furnished to do so, subject to the following conditions:
16  *
17  * The above copyright notice and this permission notice shall be included in
18  * all copies or substantial portions of the Software.
19  *
20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
23  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
25  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
26  * THE SOFTWARE.
27  */
28 
29 #include "qemu/osdep.h"
30 #include <windows.h>
31 #include "qapi/error.h"
32 #include "qemu/main-loop.h"
33 #include "trace.h"
34 #include "qemu/sockets.h"
35 #include "qemu/cutils.h"
36 #include "qemu/error-report.h"
37 #include <malloc.h>
38 
39 static int get_allocation_granularity(void)
40 {
41     SYSTEM_INFO system_info;
42 
43     GetSystemInfo(&system_info);
44     return system_info.dwAllocationGranularity;
45 }
46 
47 void *qemu_anon_ram_alloc(size_t size, uint64_t *align, bool shared,
48                           bool noreserve)
49 {
50     void *ptr;
51 
52     if (noreserve) {
53         /*
54          * We need a MEM_COMMIT before accessing any memory in a MEM_RESERVE
55          * area; we cannot easily mimic POSIX MAP_NORESERVE semantics.
56          */
57         error_report("Skipping reservation of swap space is not supported.");
58         return NULL;
59     }
60 
61     ptr = VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE);
62     trace_qemu_anon_ram_alloc(size, ptr);
63 
64     if (ptr && align) {
65         *align = MAX(get_allocation_granularity(), getpagesize());
66     }
67     return ptr;
68 }
69 
70 void qemu_anon_ram_free(void *ptr, size_t size)
71 {
72     trace_qemu_anon_ram_free(ptr, size);
73     if (ptr) {
74         VirtualFree(ptr, 0, MEM_RELEASE);
75     }
76 }
77 
78 #ifndef _POSIX_THREAD_SAFE_FUNCTIONS
79 /* FIXME: add proper locking */
80 struct tm *gmtime_r(const time_t *timep, struct tm *result)
81 {
82     struct tm *p = gmtime(timep);
83     memset(result, 0, sizeof(*result));
84     if (p) {
85         *result = *p;
86         p = result;
87     }
88     return p;
89 }
90 
91 /* FIXME: add proper locking */
92 struct tm *localtime_r(const time_t *timep, struct tm *result)
93 {
94     struct tm *p = localtime(timep);
95     memset(result, 0, sizeof(*result));
96     if (p) {
97         *result = *p;
98         p = result;
99     }
100     return p;
101 }
102 #endif /* _POSIX_THREAD_SAFE_FUNCTIONS */
103 
104 static int socket_error(void)
105 {
106     switch (WSAGetLastError()) {
107     case 0:
108         return 0;
109     case WSAEINTR:
110         return EINTR;
111     case WSAEINVAL:
112         return EINVAL;
113     case WSA_INVALID_HANDLE:
114         return EBADF;
115     case WSA_NOT_ENOUGH_MEMORY:
116         return ENOMEM;
117     case WSA_INVALID_PARAMETER:
118         return EINVAL;
119     case WSAENAMETOOLONG:
120         return ENAMETOOLONG;
121     case WSAENOTEMPTY:
122         return ENOTEMPTY;
123     case WSAEWOULDBLOCK:
124          /* not using EWOULDBLOCK as we don't want code to have
125           * to check both EWOULDBLOCK and EAGAIN */
126         return EAGAIN;
127     case WSAEINPROGRESS:
128         return EINPROGRESS;
129     case WSAEALREADY:
130         return EALREADY;
131     case WSAENOTSOCK:
132         return ENOTSOCK;
133     case WSAEDESTADDRREQ:
134         return EDESTADDRREQ;
135     case WSAEMSGSIZE:
136         return EMSGSIZE;
137     case WSAEPROTOTYPE:
138         return EPROTOTYPE;
139     case WSAENOPROTOOPT:
140         return ENOPROTOOPT;
141     case WSAEPROTONOSUPPORT:
142         return EPROTONOSUPPORT;
143     case WSAEOPNOTSUPP:
144         return EOPNOTSUPP;
145     case WSAEAFNOSUPPORT:
146         return EAFNOSUPPORT;
147     case WSAEADDRINUSE:
148         return EADDRINUSE;
149     case WSAEADDRNOTAVAIL:
150         return EADDRNOTAVAIL;
151     case WSAENETDOWN:
152         return ENETDOWN;
153     case WSAENETUNREACH:
154         return ENETUNREACH;
155     case WSAENETRESET:
156         return ENETRESET;
157     case WSAECONNABORTED:
158         return ECONNABORTED;
159     case WSAECONNRESET:
160         return ECONNRESET;
161     case WSAENOBUFS:
162         return ENOBUFS;
163     case WSAEISCONN:
164         return EISCONN;
165     case WSAENOTCONN:
166         return ENOTCONN;
167     case WSAETIMEDOUT:
168         return ETIMEDOUT;
169     case WSAECONNREFUSED:
170         return ECONNREFUSED;
171     case WSAELOOP:
172         return ELOOP;
173     case WSAEHOSTUNREACH:
174         return EHOSTUNREACH;
175     default:
176         return EIO;
177     }
178 }
179 
180 void qemu_socket_set_block(int fd)
181 {
182     unsigned long opt = 0;
183     qemu_socket_unselect(fd, NULL);
184     ioctlsocket(fd, FIONBIO, &opt);
185 }
186 
187 int qemu_socket_try_set_nonblock(int fd)
188 {
189     unsigned long opt = 1;
190     if (ioctlsocket(fd, FIONBIO, &opt) != NO_ERROR) {
191         return -socket_error();
192     }
193     return 0;
194 }
195 
196 void qemu_socket_set_nonblock(int fd)
197 {
198     (void)qemu_socket_try_set_nonblock(fd);
199 }
200 
201 int socket_set_fast_reuse(int fd)
202 {
203     /* Enabling the reuse of an endpoint that was used by a socket still in
204      * TIME_WAIT state is usually performed by setting SO_REUSEADDR. On Windows
205      * fast reuse is the default and SO_REUSEADDR does strange things. So we
206      * don't have to do anything here. More info can be found at:
207      * http://msdn.microsoft.com/en-us/library/windows/desktop/ms740621.aspx */
208     return 0;
209 }
210 
211 int inet_aton(const char *cp, struct in_addr *ia)
212 {
213     uint32_t addr = inet_addr(cp);
214     if (addr == 0xffffffff) {
215         return 0;
216     }
217     ia->s_addr = addr;
218     return 1;
219 }
220 
221 void qemu_set_cloexec(int fd)
222 {
223 }
224 
225 int qemu_get_thread_id(void)
226 {
227     return GetCurrentThreadId();
228 }
229 
230 char *
231 qemu_get_local_state_dir(void)
232 {
233     const char * const *data_dirs = g_get_system_data_dirs();
234 
235     g_assert(data_dirs && data_dirs[0]);
236 
237     return g_strdup(data_dirs[0]);
238 }
239 
240 void qemu_set_tty_echo(int fd, bool echo)
241 {
242     HANDLE handle = (HANDLE)_get_osfhandle(fd);
243     DWORD dwMode = 0;
244 
245     if (handle == INVALID_HANDLE_VALUE) {
246         return;
247     }
248 
249     GetConsoleMode(handle, &dwMode);
250 
251     if (echo) {
252         SetConsoleMode(handle, dwMode | ENABLE_ECHO_INPUT | ENABLE_LINE_INPUT);
253     } else {
254         SetConsoleMode(handle,
255                        dwMode & ~(ENABLE_ECHO_INPUT | ENABLE_LINE_INPUT));
256     }
257 }
258 
259 int getpagesize(void)
260 {
261     SYSTEM_INFO system_info;
262 
263     GetSystemInfo(&system_info);
264     return system_info.dwPageSize;
265 }
266 
267 bool qemu_prealloc_mem(int fd, char *area, size_t sz, int max_threads,
268                        ThreadContext *tc, bool async, Error **errp)
269 {
270     int i;
271     size_t pagesize = qemu_real_host_page_size();
272 
273     sz = (sz + pagesize - 1) & -pagesize;
274     for (i = 0; i < sz / pagesize; i++) {
275         memset(area + pagesize * i, 0, 1);
276     }
277 
278     return true;
279 }
280 
281 bool qemu_finish_async_prealloc_mem(Error **errp)
282 {
283     /* async prealloc not supported, there is nothing to finish */
284     return true;
285 }
286 
287 char *qemu_get_pid_name(pid_t pid)
288 {
289     /* XXX Implement me */
290     abort();
291 }
292 
293 
294 bool qemu_socket_select(int sockfd, WSAEVENT hEventObject,
295                         long lNetworkEvents, Error **errp)
296 {
297     SOCKET s = _get_osfhandle(sockfd);
298 
299     if (errp == NULL) {
300         errp = &error_warn;
301     }
302 
303     if (s == INVALID_SOCKET) {
304         error_setg(errp, "invalid socket fd=%d", sockfd);
305         return false;
306     }
307 
308     if (WSAEventSelect(s, hEventObject, lNetworkEvents) != 0) {
309         error_setg_win32(errp, WSAGetLastError(), "failed to WSAEventSelect()");
310         return false;
311     }
312 
313     return true;
314 }
315 
316 bool qemu_socket_unselect(int sockfd, Error **errp)
317 {
318     return qemu_socket_select(sockfd, NULL, 0, errp);
319 }
320 
321 int qemu_socketpair(int domain, int type, int protocol, int sv[2])
322 {
323     struct sockaddr_un addr = {
324         0,
325     };
326     socklen_t socklen;
327     int listener = -1;
328     int client = -1;
329     int server = -1;
330     g_autofree char *path = NULL;
331     int tmpfd;
332     u_long arg;
333     int ret = -1;
334 
335     g_return_val_if_fail(sv != NULL, -1);
336 
337     addr.sun_family = AF_UNIX;
338     socklen = sizeof(addr);
339 
340     tmpfd = g_file_open_tmp(NULL, &path, NULL);
341     if (tmpfd == -1 || !path) {
342         errno = EACCES;
343         goto out;
344     }
345 
346     close(tmpfd);
347 
348     if (strlen(path) >= sizeof(addr.sun_path)) {
349         errno = EINVAL;
350         goto out;
351     }
352 
353     strncpy(addr.sun_path, path, sizeof(addr.sun_path) - 1);
354 
355     listener = socket(domain, type, protocol);
356     if (listener == -1) {
357         goto out;
358     }
359 
360     if (DeleteFile(path) == 0 && GetLastError() != ERROR_FILE_NOT_FOUND) {
361         errno = EACCES;
362         goto out;
363     }
364     g_clear_pointer(&path, g_free);
365 
366     if (bind(listener, (struct sockaddr *)&addr, socklen) == -1) {
367         goto out;
368     }
369 
370     if (listen(listener, 1) == -1) {
371         goto out;
372     }
373 
374     client = socket(domain, type, protocol);
375     if (client == -1) {
376         goto out;
377     }
378 
379     arg = 1;
380     if (ioctlsocket(client, FIONBIO, &arg) != NO_ERROR) {
381         goto out;
382     }
383 
384     if (connect(client, (struct sockaddr *)&addr, socklen) == -1 &&
385         WSAGetLastError() != WSAEWOULDBLOCK) {
386         goto out;
387     }
388 
389     server = accept(listener, NULL, NULL);
390     if (server == -1) {
391         goto out;
392     }
393 
394     arg = 0;
395     if (ioctlsocket(client, FIONBIO, &arg) != NO_ERROR) {
396         goto out;
397     }
398 
399     arg = 0;
400     if (ioctlsocket(client, SIO_AF_UNIX_GETPEERPID, &arg) != NO_ERROR) {
401         goto out;
402     }
403 
404     if (arg != GetCurrentProcessId()) {
405         errno = EPERM;
406         goto out;
407     }
408 
409     sv[0] = server;
410     server = -1;
411     sv[1] = client;
412     client = -1;
413     ret = 0;
414 
415 out:
416     if (listener != -1) {
417         close(listener);
418     }
419     if (client != -1) {
420         close(client);
421     }
422     if (server != -1) {
423         close(server);
424     }
425     if (path) {
426         DeleteFile(path);
427     }
428     return ret;
429 }
430 
431 #undef connect
432 int qemu_connect_wrap(int sockfd, const struct sockaddr *addr,
433                       socklen_t addrlen)
434 {
435     int ret;
436     SOCKET s = _get_osfhandle(sockfd);
437 
438     if (s == INVALID_SOCKET) {
439         return -1;
440     }
441 
442     ret = connect(s, addr, addrlen);
443     if (ret < 0) {
444         if (WSAGetLastError() == WSAEWOULDBLOCK) {
445             errno = EINPROGRESS;
446         } else {
447             errno = socket_error();
448         }
449     }
450     return ret;
451 }
452 
453 
454 #undef listen
455 int qemu_listen_wrap(int sockfd, int backlog)
456 {
457     int ret;
458     SOCKET s = _get_osfhandle(sockfd);
459 
460     if (s == INVALID_SOCKET) {
461         return -1;
462     }
463 
464     ret = listen(s, backlog);
465     if (ret < 0) {
466         errno = socket_error();
467     }
468     return ret;
469 }
470 
471 
472 #undef bind
473 int qemu_bind_wrap(int sockfd, const struct sockaddr *addr,
474                    socklen_t addrlen)
475 {
476     int ret;
477     SOCKET s = _get_osfhandle(sockfd);
478 
479     if (s == INVALID_SOCKET) {
480         return -1;
481     }
482 
483     ret = bind(s, addr, addrlen);
484     if (ret < 0) {
485         errno = socket_error();
486     }
487     return ret;
488 }
489 
490 QEMU_USED EXCEPTION_DISPOSITION
491 win32_close_exception_handler(struct _EXCEPTION_RECORD *exception_record,
492                               void *registration, struct _CONTEXT *context,
493                               void *dispatcher)
494 {
495     return EXCEPTION_EXECUTE_HANDLER;
496 }
497 
498 #undef close
499 int qemu_close_socket_osfhandle(int fd)
500 {
501     SOCKET s = _get_osfhandle(fd);
502     DWORD flags = 0;
503 
504     /*
505      * If we were to just call _close on the descriptor, it would close the
506      * HANDLE, but it wouldn't free any of the resources associated to the
507      * SOCKET, and we can't call _close after calling closesocket, because
508      * closesocket has already closed the HANDLE, and _close would attempt to
509      * close the HANDLE again, resulting in a double free. We can however
510      * protect the HANDLE from actually being closed long enough to close the
511      * file descriptor, then close the socket itself.
512      */
513     if (!GetHandleInformation((HANDLE)s, &flags)) {
514         errno = EACCES;
515         return -1;
516     }
517 
518     if (!SetHandleInformation((HANDLE)s, HANDLE_FLAG_PROTECT_FROM_CLOSE, HANDLE_FLAG_PROTECT_FROM_CLOSE)) {
519         errno = EACCES;
520         return -1;
521     }
522 
523     __try1(win32_close_exception_handler) {
524         /*
525          * close() returns EBADF since we PROTECT_FROM_CLOSE the underlying
526          * handle, but the FD is actually freed
527          */
528         if (close(fd) < 0 && errno != EBADF) {
529             return -1;
530         }
531     }
532     __except1 {
533     }
534 
535     if (!SetHandleInformation((HANDLE)s, flags, flags)) {
536         errno = EACCES;
537         return -1;
538     }
539 
540     return 0;
541 }
542 
543 int qemu_close_wrap(int fd)
544 {
545     SOCKET s = INVALID_SOCKET;
546     int ret = -1;
547 
548     if (!fd_is_socket(fd)) {
549         return close(fd);
550     }
551 
552     s = _get_osfhandle(fd);
553     qemu_close_socket_osfhandle(fd);
554 
555     ret = closesocket(s);
556     if (ret < 0) {
557         errno = socket_error();
558     }
559 
560     return ret;
561 }
562 
563 
564 #undef socket
565 int qemu_socket_wrap(int domain, int type, int protocol)
566 {
567     SOCKET s;
568     int fd;
569 
570     s = socket(domain, type, protocol);
571     if (s == -1) {
572         errno = socket_error();
573         return -1;
574     }
575 
576     fd = _open_osfhandle(s, _O_BINARY);
577     if (fd < 0) {
578         closesocket(s);
579         /* _open_osfhandle may not set errno, and closesocket() may override it */
580         errno = ENOMEM;
581     }
582 
583     return fd;
584 }
585 
586 
587 #undef accept
588 int qemu_accept_wrap(int sockfd, struct sockaddr *addr,
589                      socklen_t *addrlen)
590 {
591     int fd;
592     SOCKET s = _get_osfhandle(sockfd);
593 
594     if (s == INVALID_SOCKET) {
595         return -1;
596     }
597 
598     s = accept(s, addr, addrlen);
599     if (s == -1) {
600         errno = socket_error();
601         return -1;
602     }
603 
604     fd = _open_osfhandle(s, _O_BINARY);
605     if (fd < 0) {
606         closesocket(s);
607         /* _open_osfhandle may not set errno, and closesocket() may override it */
608         errno = ENOMEM;
609     }
610 
611     return fd;
612 }
613 
614 
615 #undef shutdown
616 int qemu_shutdown_wrap(int sockfd, int how)
617 {
618     int ret;
619     SOCKET s = _get_osfhandle(sockfd);
620 
621     if (s == INVALID_SOCKET) {
622         return -1;
623     }
624 
625     ret = shutdown(s, how);
626     if (ret < 0) {
627         errno = socket_error();
628     }
629     return ret;
630 }
631 
632 
633 #undef ioctlsocket
634 int qemu_ioctlsocket_wrap(int fd, int req, void *val)
635 {
636     int ret;
637     SOCKET s = _get_osfhandle(fd);
638 
639     if (s == INVALID_SOCKET) {
640         return -1;
641     }
642 
643     ret = ioctlsocket(s, req, val);
644     if (ret < 0) {
645         errno = socket_error();
646     }
647     return ret;
648 }
649 
650 
651 #undef getsockopt
652 int qemu_getsockopt_wrap(int sockfd, int level, int optname,
653                          void *optval, socklen_t *optlen)
654 {
655     int ret;
656     SOCKET s = _get_osfhandle(sockfd);
657 
658     if (s == INVALID_SOCKET) {
659         return -1;
660     }
661 
662     ret = getsockopt(s, level, optname, optval, optlen);
663     if (ret < 0) {
664         errno = socket_error();
665     }
666     return ret;
667 }
668 
669 
670 #undef setsockopt
671 int qemu_setsockopt_wrap(int sockfd, int level, int optname,
672                          const void *optval, socklen_t optlen)
673 {
674     int ret;
675     SOCKET s = _get_osfhandle(sockfd);
676 
677     if (s == INVALID_SOCKET) {
678         return -1;
679     }
680 
681     ret = setsockopt(s, level, optname, optval, optlen);
682     if (ret < 0) {
683         errno = socket_error();
684     }
685     return ret;
686 }
687 
688 
689 #undef getpeername
690 int qemu_getpeername_wrap(int sockfd, struct sockaddr *addr,
691                           socklen_t *addrlen)
692 {
693     int ret;
694     SOCKET s = _get_osfhandle(sockfd);
695 
696     if (s == INVALID_SOCKET) {
697         return -1;
698     }
699 
700     ret = getpeername(s, addr, addrlen);
701     if (ret < 0) {
702         errno = socket_error();
703     }
704     return ret;
705 }
706 
707 
708 #undef getsockname
709 int qemu_getsockname_wrap(int sockfd, struct sockaddr *addr,
710                           socklen_t *addrlen)
711 {
712     int ret;
713     SOCKET s = _get_osfhandle(sockfd);
714 
715     if (s == INVALID_SOCKET) {
716         return -1;
717     }
718 
719     ret = getsockname(s, addr, addrlen);
720     if (ret < 0) {
721         errno = socket_error();
722     }
723     return ret;
724 }
725 
726 
727 #undef send
728 ssize_t qemu_send_wrap(int sockfd, const void *buf, size_t len, int flags)
729 {
730     int ret;
731     SOCKET s = _get_osfhandle(sockfd);
732 
733     if (s == INVALID_SOCKET) {
734         return -1;
735     }
736 
737     ret = send(s, buf, len, flags);
738     if (ret < 0) {
739         errno = socket_error();
740     }
741     return ret;
742 }
743 
744 
745 #undef sendto
746 ssize_t qemu_sendto_wrap(int sockfd, const void *buf, size_t len, int flags,
747                          const struct sockaddr *addr, socklen_t addrlen)
748 {
749     int ret;
750     SOCKET s = _get_osfhandle(sockfd);
751 
752     if (s == INVALID_SOCKET) {
753         return -1;
754     }
755 
756     ret = sendto(s, buf, len, flags, addr, addrlen);
757     if (ret < 0) {
758         errno = socket_error();
759     }
760     return ret;
761 }
762 
763 
764 #undef recv
765 ssize_t qemu_recv_wrap(int sockfd, void *buf, size_t len, int flags)
766 {
767     int ret;
768     SOCKET s = _get_osfhandle(sockfd);
769 
770     if (s == INVALID_SOCKET) {
771         return -1;
772     }
773 
774     ret = recv(s, buf, len, flags);
775     if (ret < 0) {
776         errno = socket_error();
777     }
778     return ret;
779 }
780 
781 
782 #undef recvfrom
783 ssize_t qemu_recvfrom_wrap(int sockfd, void *buf, size_t len, int flags,
784                            struct sockaddr *addr, socklen_t *addrlen)
785 {
786     int ret;
787     SOCKET s = _get_osfhandle(sockfd);
788 
789     if (s == INVALID_SOCKET) {
790         return -1;
791     }
792 
793     ret = recvfrom(s, buf, len, flags, addr, addrlen);
794     if (ret < 0) {
795         errno = socket_error();
796     }
797     return ret;
798 }
799 
800 bool qemu_write_pidfile(const char *filename, Error **errp)
801 {
802     char buffer[128];
803     int len;
804     HANDLE file;
805     OVERLAPPED overlap;
806     BOOL ret;
807     memset(&overlap, 0, sizeof(overlap));
808 
809     file = CreateFile(filename, GENERIC_WRITE, FILE_SHARE_READ, NULL,
810                       OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
811 
812     if (file == INVALID_HANDLE_VALUE) {
813         error_setg(errp, "Failed to create PID file");
814         return false;
815     }
816     len = snprintf(buffer, sizeof(buffer), FMT_pid "\n", (pid_t)getpid());
817     ret = WriteFile(file, (LPCVOID)buffer, (DWORD)len,
818                     NULL, &overlap);
819     CloseHandle(file);
820     if (ret == 0) {
821         error_setg(errp, "Failed to write PID file");
822         return false;
823     }
824     return true;
825 }
826 
827 size_t qemu_get_host_physmem(void)
828 {
829     MEMORYSTATUSEX statex;
830     statex.dwLength = sizeof(statex);
831 
832     if (GlobalMemoryStatusEx(&statex)) {
833         return statex.ullTotalPhys;
834     }
835     return 0;
836 }
837 
838 int qemu_msync(void *addr, size_t length, int fd)
839 {
840     /**
841      * Perform the sync based on the file descriptor
842      * The sync range will most probably be wider than the one
843      * requested - but it will still get the job done
844      */
845     return qemu_fdatasync(fd);
846 }
847 
848 void *qemu_win32_map_alloc(size_t size, HANDLE *h, Error **errp)
849 {
850     void *bits;
851 
852     trace_win32_map_alloc(size);
853 
854     *h = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0,
855                           size, NULL);
856     if (*h == NULL) {
857         error_setg_win32(errp, GetLastError(), "Failed to CreateFileMapping");
858         return NULL;
859     }
860 
861     bits = MapViewOfFile(*h, FILE_MAP_ALL_ACCESS, 0, 0, size);
862     if (bits == NULL) {
863         error_setg_win32(errp, GetLastError(), "Failed to MapViewOfFile");
864         CloseHandle(*h);
865         return NULL;
866     }
867 
868     return bits;
869 }
870 
871 void qemu_win32_map_free(void *ptr, HANDLE h, Error **errp)
872 {
873     trace_win32_map_free(ptr, h);
874 
875     if (UnmapViewOfFile(ptr) == 0) {
876         error_setg_win32(errp, GetLastError(), "Failed to UnmapViewOfFile");
877     }
878     CloseHandle(h);
879 }
880