xref: /openbmc/qemu/util/oslib-win32.c (revision dbdf841b)
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 void qemu_prealloc_mem(int fd, char *area, size_t sz, int max_threads,
268                        ThreadContext *tc, 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 
279 char *qemu_get_pid_name(pid_t pid)
280 {
281     /* XXX Implement me */
282     abort();
283 }
284 
285 
286 bool qemu_socket_select(int sockfd, WSAEVENT hEventObject,
287                         long lNetworkEvents, Error **errp)
288 {
289     SOCKET s = _get_osfhandle(sockfd);
290 
291     if (errp == NULL) {
292         errp = &error_warn;
293     }
294 
295     if (s == INVALID_SOCKET) {
296         error_setg(errp, "invalid socket fd=%d", sockfd);
297         return false;
298     }
299 
300     if (WSAEventSelect(s, hEventObject, lNetworkEvents) != 0) {
301         error_setg_win32(errp, WSAGetLastError(), "failed to WSAEventSelect()");
302         return false;
303     }
304 
305     return true;
306 }
307 
308 bool qemu_socket_unselect(int sockfd, Error **errp)
309 {
310     return qemu_socket_select(sockfd, NULL, 0, errp);
311 }
312 
313 int qemu_socketpair(int domain, int type, int protocol, int sv[2])
314 {
315     struct sockaddr_un addr = {
316         0,
317     };
318     socklen_t socklen;
319     int listener = -1;
320     int client = -1;
321     int server = -1;
322     g_autofree char *path = NULL;
323     int tmpfd;
324     u_long arg;
325     int ret = -1;
326 
327     g_return_val_if_fail(sv != NULL, -1);
328 
329     addr.sun_family = AF_UNIX;
330     socklen = sizeof(addr);
331 
332     tmpfd = g_file_open_tmp(NULL, &path, NULL);
333     if (tmpfd == -1 || !path) {
334         errno = EACCES;
335         goto out;
336     }
337 
338     close(tmpfd);
339 
340     if (strlen(path) >= sizeof(addr.sun_path)) {
341         errno = EINVAL;
342         goto out;
343     }
344 
345     strncpy(addr.sun_path, path, sizeof(addr.sun_path) - 1);
346 
347     listener = socket(domain, type, protocol);
348     if (listener == -1) {
349         goto out;
350     }
351 
352     if (DeleteFile(path) == 0 && GetLastError() != ERROR_FILE_NOT_FOUND) {
353         errno = EACCES;
354         goto out;
355     }
356     g_clear_pointer(&path, g_free);
357 
358     if (bind(listener, (struct sockaddr *)&addr, socklen) == -1) {
359         goto out;
360     }
361 
362     if (listen(listener, 1) == -1) {
363         goto out;
364     }
365 
366     client = socket(domain, type, protocol);
367     if (client == -1) {
368         goto out;
369     }
370 
371     arg = 1;
372     if (ioctlsocket(client, FIONBIO, &arg) != NO_ERROR) {
373         goto out;
374     }
375 
376     if (connect(client, (struct sockaddr *)&addr, socklen) == -1 &&
377         WSAGetLastError() != WSAEWOULDBLOCK) {
378         goto out;
379     }
380 
381     server = accept(listener, NULL, NULL);
382     if (server == -1) {
383         goto out;
384     }
385 
386     arg = 0;
387     if (ioctlsocket(client, FIONBIO, &arg) != NO_ERROR) {
388         goto out;
389     }
390 
391     arg = 0;
392     if (ioctlsocket(client, SIO_AF_UNIX_GETPEERPID, &arg) != NO_ERROR) {
393         goto out;
394     }
395 
396     if (arg != GetCurrentProcessId()) {
397         errno = EPERM;
398         goto out;
399     }
400 
401     sv[0] = server;
402     server = -1;
403     sv[1] = client;
404     client = -1;
405     ret = 0;
406 
407 out:
408     if (listener != -1) {
409         close(listener);
410     }
411     if (client != -1) {
412         close(client);
413     }
414     if (server != -1) {
415         close(server);
416     }
417     if (path) {
418         DeleteFile(path);
419     }
420     return ret;
421 }
422 
423 #undef connect
424 int qemu_connect_wrap(int sockfd, const struct sockaddr *addr,
425                       socklen_t addrlen)
426 {
427     int ret;
428     SOCKET s = _get_osfhandle(sockfd);
429 
430     if (s == INVALID_SOCKET) {
431         return -1;
432     }
433 
434     ret = connect(s, addr, addrlen);
435     if (ret < 0) {
436         if (WSAGetLastError() == WSAEWOULDBLOCK) {
437             errno = EINPROGRESS;
438         } else {
439             errno = socket_error();
440         }
441     }
442     return ret;
443 }
444 
445 
446 #undef listen
447 int qemu_listen_wrap(int sockfd, int backlog)
448 {
449     int ret;
450     SOCKET s = _get_osfhandle(sockfd);
451 
452     if (s == INVALID_SOCKET) {
453         return -1;
454     }
455 
456     ret = listen(s, backlog);
457     if (ret < 0) {
458         errno = socket_error();
459     }
460     return ret;
461 }
462 
463 
464 #undef bind
465 int qemu_bind_wrap(int sockfd, const struct sockaddr *addr,
466                    socklen_t addrlen)
467 {
468     int ret;
469     SOCKET s = _get_osfhandle(sockfd);
470 
471     if (s == INVALID_SOCKET) {
472         return -1;
473     }
474 
475     ret = bind(s, addr, addrlen);
476     if (ret < 0) {
477         errno = socket_error();
478     }
479     return ret;
480 }
481 
482 EXCEPTION_DISPOSITION
483 win32_close_exception_handler(struct _EXCEPTION_RECORD*,
484                               void*, struct _CONTEXT*, void*)
485 {
486     return EXCEPTION_EXECUTE_HANDLER;
487 }
488 
489 #undef close
490 int qemu_close_socket_osfhandle(int fd)
491 {
492     SOCKET s = _get_osfhandle(fd);
493     DWORD flags = 0;
494 
495     /*
496      * If we were to just call _close on the descriptor, it would close the
497      * HANDLE, but it wouldn't free any of the resources associated to the
498      * SOCKET, and we can't call _close after calling closesocket, because
499      * closesocket has already closed the HANDLE, and _close would attempt to
500      * close the HANDLE again, resulting in a double free. We can however
501      * protect the HANDLE from actually being closed long enough to close the
502      * file descriptor, then close the socket itself.
503      */
504     if (!GetHandleInformation((HANDLE)s, &flags)) {
505         errno = EACCES;
506         return -1;
507     }
508 
509     if (!SetHandleInformation((HANDLE)s, HANDLE_FLAG_PROTECT_FROM_CLOSE, HANDLE_FLAG_PROTECT_FROM_CLOSE)) {
510         errno = EACCES;
511         return -1;
512     }
513 
514     __try1(win32_close_exception_handler) {
515         /*
516          * close() returns EBADF since we PROTECT_FROM_CLOSE the underlying
517          * handle, but the FD is actually freed
518          */
519         if (close(fd) < 0 && errno != EBADF) {
520             return -1;
521         }
522     }
523     __except1 {
524     }
525 
526     if (!SetHandleInformation((HANDLE)s, flags, flags)) {
527         errno = EACCES;
528         return -1;
529     }
530 
531     return 0;
532 }
533 
534 int qemu_close_wrap(int fd)
535 {
536     SOCKET s = INVALID_SOCKET;
537     int ret = -1;
538 
539     if (!fd_is_socket(fd)) {
540         return close(fd);
541     }
542 
543     s = _get_osfhandle(fd);
544     qemu_close_socket_osfhandle(fd);
545 
546     ret = closesocket(s);
547     if (ret < 0) {
548         errno = socket_error();
549     }
550 
551     return ret;
552 }
553 
554 
555 #undef socket
556 int qemu_socket_wrap(int domain, int type, int protocol)
557 {
558     SOCKET s;
559     int fd;
560 
561     s = socket(domain, type, protocol);
562     if (s == -1) {
563         errno = socket_error();
564         return -1;
565     }
566 
567     fd = _open_osfhandle(s, _O_BINARY);
568     if (fd < 0) {
569         closesocket(s);
570         /* _open_osfhandle may not set errno, and closesocket() may override it */
571         errno = ENOMEM;
572     }
573 
574     return fd;
575 }
576 
577 
578 #undef accept
579 int qemu_accept_wrap(int sockfd, struct sockaddr *addr,
580                      socklen_t *addrlen)
581 {
582     int fd;
583     SOCKET s = _get_osfhandle(sockfd);
584 
585     if (s == INVALID_SOCKET) {
586         return -1;
587     }
588 
589     s = accept(s, addr, addrlen);
590     if (s == -1) {
591         errno = socket_error();
592         return -1;
593     }
594 
595     fd = _open_osfhandle(s, _O_BINARY);
596     if (fd < 0) {
597         closesocket(s);
598         /* _open_osfhandle may not set errno, and closesocket() may override it */
599         errno = ENOMEM;
600     }
601 
602     return fd;
603 }
604 
605 
606 #undef shutdown
607 int qemu_shutdown_wrap(int sockfd, int how)
608 {
609     int ret;
610     SOCKET s = _get_osfhandle(sockfd);
611 
612     if (s == INVALID_SOCKET) {
613         return -1;
614     }
615 
616     ret = shutdown(s, how);
617     if (ret < 0) {
618         errno = socket_error();
619     }
620     return ret;
621 }
622 
623 
624 #undef ioctlsocket
625 int qemu_ioctlsocket_wrap(int fd, int req, void *val)
626 {
627     int ret;
628     SOCKET s = _get_osfhandle(fd);
629 
630     if (s == INVALID_SOCKET) {
631         return -1;
632     }
633 
634     ret = ioctlsocket(s, req, val);
635     if (ret < 0) {
636         errno = socket_error();
637     }
638     return ret;
639 }
640 
641 
642 #undef getsockopt
643 int qemu_getsockopt_wrap(int sockfd, int level, int optname,
644                          void *optval, socklen_t *optlen)
645 {
646     int ret;
647     SOCKET s = _get_osfhandle(sockfd);
648 
649     if (s == INVALID_SOCKET) {
650         return -1;
651     }
652 
653     ret = getsockopt(s, level, optname, optval, optlen);
654     if (ret < 0) {
655         errno = socket_error();
656     }
657     return ret;
658 }
659 
660 
661 #undef setsockopt
662 int qemu_setsockopt_wrap(int sockfd, int level, int optname,
663                          const void *optval, socklen_t optlen)
664 {
665     int ret;
666     SOCKET s = _get_osfhandle(sockfd);
667 
668     if (s == INVALID_SOCKET) {
669         return -1;
670     }
671 
672     ret = setsockopt(s, level, optname, optval, optlen);
673     if (ret < 0) {
674         errno = socket_error();
675     }
676     return ret;
677 }
678 
679 
680 #undef getpeername
681 int qemu_getpeername_wrap(int sockfd, struct sockaddr *addr,
682                           socklen_t *addrlen)
683 {
684     int ret;
685     SOCKET s = _get_osfhandle(sockfd);
686 
687     if (s == INVALID_SOCKET) {
688         return -1;
689     }
690 
691     ret = getpeername(s, addr, addrlen);
692     if (ret < 0) {
693         errno = socket_error();
694     }
695     return ret;
696 }
697 
698 
699 #undef getsockname
700 int qemu_getsockname_wrap(int sockfd, struct sockaddr *addr,
701                           socklen_t *addrlen)
702 {
703     int ret;
704     SOCKET s = _get_osfhandle(sockfd);
705 
706     if (s == INVALID_SOCKET) {
707         return -1;
708     }
709 
710     ret = getsockname(s, addr, addrlen);
711     if (ret < 0) {
712         errno = socket_error();
713     }
714     return ret;
715 }
716 
717 
718 #undef send
719 ssize_t qemu_send_wrap(int sockfd, const void *buf, size_t len, int flags)
720 {
721     int ret;
722     SOCKET s = _get_osfhandle(sockfd);
723 
724     if (s == INVALID_SOCKET) {
725         return -1;
726     }
727 
728     ret = send(s, buf, len, flags);
729     if (ret < 0) {
730         errno = socket_error();
731     }
732     return ret;
733 }
734 
735 
736 #undef sendto
737 ssize_t qemu_sendto_wrap(int sockfd, const void *buf, size_t len, int flags,
738                          const struct sockaddr *addr, socklen_t addrlen)
739 {
740     int ret;
741     SOCKET s = _get_osfhandle(sockfd);
742 
743     if (s == INVALID_SOCKET) {
744         return -1;
745     }
746 
747     ret = sendto(s, buf, len, flags, addr, addrlen);
748     if (ret < 0) {
749         errno = socket_error();
750     }
751     return ret;
752 }
753 
754 
755 #undef recv
756 ssize_t qemu_recv_wrap(int sockfd, void *buf, size_t len, int flags)
757 {
758     int ret;
759     SOCKET s = _get_osfhandle(sockfd);
760 
761     if (s == INVALID_SOCKET) {
762         return -1;
763     }
764 
765     ret = recv(s, buf, len, flags);
766     if (ret < 0) {
767         errno = socket_error();
768     }
769     return ret;
770 }
771 
772 
773 #undef recvfrom
774 ssize_t qemu_recvfrom_wrap(int sockfd, void *buf, size_t len, int flags,
775                            struct sockaddr *addr, socklen_t *addrlen)
776 {
777     int ret;
778     SOCKET s = _get_osfhandle(sockfd);
779 
780     if (s == INVALID_SOCKET) {
781         return -1;
782     }
783 
784     ret = recvfrom(s, buf, len, flags, addr, addrlen);
785     if (ret < 0) {
786         errno = socket_error();
787     }
788     return ret;
789 }
790 
791 bool qemu_write_pidfile(const char *filename, Error **errp)
792 {
793     char buffer[128];
794     int len;
795     HANDLE file;
796     OVERLAPPED overlap;
797     BOOL ret;
798     memset(&overlap, 0, sizeof(overlap));
799 
800     file = CreateFile(filename, GENERIC_WRITE, FILE_SHARE_READ, NULL,
801                       OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
802 
803     if (file == INVALID_HANDLE_VALUE) {
804         error_setg(errp, "Failed to create PID file");
805         return false;
806     }
807     len = snprintf(buffer, sizeof(buffer), FMT_pid "\n", (pid_t)getpid());
808     ret = WriteFile(file, (LPCVOID)buffer, (DWORD)len,
809                     NULL, &overlap);
810     CloseHandle(file);
811     if (ret == 0) {
812         error_setg(errp, "Failed to write PID file");
813         return false;
814     }
815     return true;
816 }
817 
818 size_t qemu_get_host_physmem(void)
819 {
820     MEMORYSTATUSEX statex;
821     statex.dwLength = sizeof(statex);
822 
823     if (GlobalMemoryStatusEx(&statex)) {
824         return statex.ullTotalPhys;
825     }
826     return 0;
827 }
828 
829 int qemu_msync(void *addr, size_t length, int fd)
830 {
831     /**
832      * Perform the sync based on the file descriptor
833      * The sync range will most probably be wider than the one
834      * requested - but it will still get the job done
835      */
836     return qemu_fdatasync(fd);
837 }
838 
839 void *qemu_win32_map_alloc(size_t size, HANDLE *h, Error **errp)
840 {
841     void *bits;
842 
843     trace_win32_map_alloc(size);
844 
845     *h = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0,
846                           size, NULL);
847     if (*h == NULL) {
848         error_setg_win32(errp, GetLastError(), "Failed to CreateFileMapping");
849         return NULL;
850     }
851 
852     bits = MapViewOfFile(*h, FILE_MAP_ALL_ACCESS, 0, 0, size);
853     if (bits == NULL) {
854         error_setg_win32(errp, GetLastError(), "Failed to MapViewOfFile");
855         CloseHandle(*h);
856         return NULL;
857     }
858 
859     return bits;
860 }
861 
862 void qemu_win32_map_free(void *ptr, HANDLE h, Error **errp)
863 {
864     trace_win32_map_free(ptr, h);
865 
866     if (UnmapViewOfFile(ptr) == 0) {
867         error_setg_win32(errp, GetLastError(), "Failed to UnmapViewOfFile");
868     }
869     CloseHandle(h);
870 }
871