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![Philippe Mathieu-Daudé](/assets/img/avatar_default.png)
Commit06680b15b4
moved qemu_*_exec_dir() to cutils but forgot to move the macOS dyld(3) include, resulting in the following error (when building with Homebrew GCC on macOS Monterey 12.4): [313/1197] Compiling C object libqemuutil.a.p/util_cutils.c.o FAILED: libqemuutil.a.p/util_cutils.c.o ../../util/cutils.c:1039:13: error: implicit declaration of function '_NSGetExecutablePath' [-Werror=implicit-function-declaration] 1039 | if (_NSGetExecutablePath(fpath, &len) == 0) { | ^~~~~~~~~~~~~~~~~~~~ ../../util/cutils.c:1039:13: error: nested extern declaration of '_NSGetExecutablePath' [-Werror=nested-externs] Fix by moving the include line to cutils. Fixes:06680b15b4
("include: move qemu_*_exec_dir() to cutils") Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Message-id: 20220809222046.30812-1-f4bug@amsat.org Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
793 lines
22 KiB
C
793 lines
22 KiB
C
/*
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* os-posix-lib.c
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*
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* Copyright (c) 2003-2008 Fabrice Bellard
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* Copyright (c) 2010 Red Hat, Inc.
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*
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* QEMU library functions on POSIX which are shared between QEMU and
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* the QEMU tools.
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "qemu/osdep.h"
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#include <termios.h>
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#include <glib/gprintf.h>
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#include "sysemu/sysemu.h"
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#include "trace.h"
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#include "qapi/error.h"
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#include "qemu/error-report.h"
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#include "qemu/madvise.h"
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#include "qemu/sockets.h"
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#include "qemu/thread.h"
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#include <libgen.h>
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#include "qemu/cutils.h"
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#include "qemu/compiler.h"
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#include "qemu/units.h"
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#ifdef CONFIG_LINUX
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#include <sys/syscall.h>
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#endif
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#ifdef __FreeBSD__
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#include <sys/thr.h>
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#include <sys/types.h>
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#include <sys/user.h>
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#include <libutil.h>
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#endif
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#ifdef __NetBSD__
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#include <lwp.h>
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#endif
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#include "qemu/mmap-alloc.h"
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#ifdef CONFIG_DEBUG_STACK_USAGE
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#include "qemu/error-report.h"
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#endif
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#define MAX_MEM_PREALLOC_THREAD_COUNT 16
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struct MemsetThread;
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typedef struct MemsetContext {
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bool all_threads_created;
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bool any_thread_failed;
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struct MemsetThread *threads;
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int num_threads;
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} MemsetContext;
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struct MemsetThread {
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char *addr;
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size_t numpages;
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size_t hpagesize;
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QemuThread pgthread;
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sigjmp_buf env;
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MemsetContext *context;
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};
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typedef struct MemsetThread MemsetThread;
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/* used by sigbus_handler() */
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static MemsetContext *sigbus_memset_context;
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struct sigaction sigbus_oldact;
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static QemuMutex sigbus_mutex;
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static QemuMutex page_mutex;
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static QemuCond page_cond;
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int qemu_get_thread_id(void)
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{
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#if defined(__linux__)
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return syscall(SYS_gettid);
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#elif defined(__FreeBSD__)
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/* thread id is up to INT_MAX */
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long tid;
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thr_self(&tid);
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return (int)tid;
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#elif defined(__NetBSD__)
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return _lwp_self();
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#elif defined(__OpenBSD__)
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return getthrid();
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#else
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return getpid();
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#endif
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}
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int qemu_daemon(int nochdir, int noclose)
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{
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return daemon(nochdir, noclose);
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}
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bool qemu_write_pidfile(const char *path, Error **errp)
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{
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int fd;
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char pidstr[32];
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while (1) {
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struct stat a, b;
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struct flock lock = {
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.l_type = F_WRLCK,
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.l_whence = SEEK_SET,
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.l_len = 0,
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};
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fd = qemu_create(path, O_WRONLY, S_IRUSR | S_IWUSR, errp);
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if (fd == -1) {
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return false;
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}
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if (fstat(fd, &b) < 0) {
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error_setg_errno(errp, errno, "Cannot stat file");
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goto fail_close;
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}
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if (fcntl(fd, F_SETLK, &lock)) {
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error_setg_errno(errp, errno, "Cannot lock pid file");
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goto fail_close;
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}
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/*
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* Now make sure the path we locked is the same one that now
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* exists on the filesystem.
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*/
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if (stat(path, &a) < 0) {
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/*
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* PID file disappeared, someone else must be racing with
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* us, so try again.
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*/
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close(fd);
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continue;
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}
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if (a.st_ino == b.st_ino) {
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break;
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}
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/*
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* PID file was recreated, someone else must be racing with
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* us, so try again.
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*/
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close(fd);
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}
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if (ftruncate(fd, 0) < 0) {
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error_setg_errno(errp, errno, "Failed to truncate pid file");
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goto fail_unlink;
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}
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snprintf(pidstr, sizeof(pidstr), FMT_pid "\n", getpid());
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if (qemu_write_full(fd, pidstr, strlen(pidstr)) != strlen(pidstr)) {
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error_setg(errp, "Failed to write pid file");
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goto fail_unlink;
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}
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return true;
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fail_unlink:
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unlink(path);
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fail_close:
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close(fd);
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return false;
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}
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/* alloc shared memory pages */
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void *qemu_anon_ram_alloc(size_t size, uint64_t *alignment, bool shared,
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bool noreserve)
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{
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const uint32_t qemu_map_flags = (shared ? QEMU_MAP_SHARED : 0) |
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(noreserve ? QEMU_MAP_NORESERVE : 0);
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size_t align = QEMU_VMALLOC_ALIGN;
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void *ptr = qemu_ram_mmap(-1, size, align, qemu_map_flags, 0);
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if (ptr == MAP_FAILED) {
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return NULL;
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}
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if (alignment) {
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*alignment = align;
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}
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trace_qemu_anon_ram_alloc(size, ptr);
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return ptr;
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}
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void qemu_anon_ram_free(void *ptr, size_t size)
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{
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trace_qemu_anon_ram_free(ptr, size);
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qemu_ram_munmap(-1, ptr, size);
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}
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void qemu_socket_set_block(int fd)
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{
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g_unix_set_fd_nonblocking(fd, false, NULL);
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}
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int qemu_socket_try_set_nonblock(int fd)
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{
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return g_unix_set_fd_nonblocking(fd, true, NULL) ? 0 : -errno;
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}
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void qemu_socket_set_nonblock(int fd)
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{
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int f;
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f = qemu_socket_try_set_nonblock(fd);
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assert(f == 0);
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}
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int socket_set_fast_reuse(int fd)
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{
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int val = 1, ret;
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ret = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
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(const char *)&val, sizeof(val));
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assert(ret == 0);
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return ret;
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}
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void qemu_set_cloexec(int fd)
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{
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int f;
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f = fcntl(fd, F_GETFD);
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assert(f != -1);
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f = fcntl(fd, F_SETFD, f | FD_CLOEXEC);
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assert(f != -1);
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}
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char *
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qemu_get_local_state_dir(void)
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{
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return get_relocated_path(CONFIG_QEMU_LOCALSTATEDIR);
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}
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void qemu_set_tty_echo(int fd, bool echo)
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{
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struct termios tty;
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tcgetattr(fd, &tty);
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if (echo) {
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tty.c_lflag |= ECHO | ECHONL | ICANON | IEXTEN;
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} else {
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tty.c_lflag &= ~(ECHO | ECHONL | ICANON | IEXTEN);
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}
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tcsetattr(fd, TCSANOW, &tty);
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}
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#ifdef CONFIG_LINUX
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static void sigbus_handler(int signal, siginfo_t *siginfo, void *ctx)
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#else /* CONFIG_LINUX */
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static void sigbus_handler(int signal)
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#endif /* CONFIG_LINUX */
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{
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int i;
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if (sigbus_memset_context) {
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for (i = 0; i < sigbus_memset_context->num_threads; i++) {
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MemsetThread *thread = &sigbus_memset_context->threads[i];
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if (qemu_thread_is_self(&thread->pgthread)) {
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siglongjmp(thread->env, 1);
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}
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}
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}
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#ifdef CONFIG_LINUX
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/*
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* We assume that the MCE SIGBUS handler could have been registered. We
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* should never receive BUS_MCEERR_AO on any of our threads, but only on
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* the main thread registered for PR_MCE_KILL_EARLY. Further, we should not
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* receive BUS_MCEERR_AR triggered by action of other threads on one of
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* our threads. So, no need to check for unrelated SIGBUS when seeing one
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* for our threads.
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*
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* We will forward to the MCE handler, which will either handle the SIGBUS
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* or reinstall the default SIGBUS handler and reraise the SIGBUS. The
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* default SIGBUS handler will crash the process, so we don't care.
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*/
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if (sigbus_oldact.sa_flags & SA_SIGINFO) {
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sigbus_oldact.sa_sigaction(signal, siginfo, ctx);
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return;
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}
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#endif /* CONFIG_LINUX */
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warn_report("os_mem_prealloc: unrelated SIGBUS detected and ignored");
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}
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static void *do_touch_pages(void *arg)
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{
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MemsetThread *memset_args = (MemsetThread *)arg;
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sigset_t set, oldset;
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int ret = 0;
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/*
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* On Linux, the page faults from the loop below can cause mmap_sem
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* contention with allocation of the thread stacks. Do not start
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* clearing until all threads have been created.
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*/
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qemu_mutex_lock(&page_mutex);
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while (!memset_args->context->all_threads_created) {
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qemu_cond_wait(&page_cond, &page_mutex);
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}
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qemu_mutex_unlock(&page_mutex);
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/* unblock SIGBUS */
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sigemptyset(&set);
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sigaddset(&set, SIGBUS);
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pthread_sigmask(SIG_UNBLOCK, &set, &oldset);
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if (sigsetjmp(memset_args->env, 1)) {
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ret = -EFAULT;
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} else {
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char *addr = memset_args->addr;
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size_t numpages = memset_args->numpages;
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size_t hpagesize = memset_args->hpagesize;
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size_t i;
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for (i = 0; i < numpages; i++) {
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/*
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* Read & write back the same value, so we don't
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* corrupt existing user/app data that might be
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* stored.
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*
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* 'volatile' to stop compiler optimizing this away
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* to a no-op
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*/
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*(volatile char *)addr = *addr;
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addr += hpagesize;
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}
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}
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pthread_sigmask(SIG_SETMASK, &oldset, NULL);
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return (void *)(uintptr_t)ret;
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}
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static void *do_madv_populate_write_pages(void *arg)
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{
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MemsetThread *memset_args = (MemsetThread *)arg;
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const size_t size = memset_args->numpages * memset_args->hpagesize;
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char * const addr = memset_args->addr;
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int ret = 0;
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/* See do_touch_pages(). */
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qemu_mutex_lock(&page_mutex);
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while (!memset_args->context->all_threads_created) {
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qemu_cond_wait(&page_cond, &page_mutex);
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}
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qemu_mutex_unlock(&page_mutex);
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if (size && qemu_madvise(addr, size, QEMU_MADV_POPULATE_WRITE)) {
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ret = -errno;
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}
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return (void *)(uintptr_t)ret;
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}
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static inline int get_memset_num_threads(size_t hpagesize, size_t numpages,
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int smp_cpus)
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{
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long host_procs = sysconf(_SC_NPROCESSORS_ONLN);
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int ret = 1;
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if (host_procs > 0) {
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ret = MIN(MIN(host_procs, MAX_MEM_PREALLOC_THREAD_COUNT), smp_cpus);
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}
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/* Especially with gigantic pages, don't create more threads than pages. */
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ret = MIN(ret, numpages);
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/* Don't start threads to prealloc comparatively little memory. */
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ret = MIN(ret, MAX(1, hpagesize * numpages / (64 * MiB)));
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/* In case sysconf() fails, we fall back to single threaded */
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return ret;
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}
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static int touch_all_pages(char *area, size_t hpagesize, size_t numpages,
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int smp_cpus, bool use_madv_populate_write)
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{
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static gsize initialized = 0;
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MemsetContext context = {
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.num_threads = get_memset_num_threads(hpagesize, numpages, smp_cpus),
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};
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size_t numpages_per_thread, leftover;
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void *(*touch_fn)(void *);
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int ret = 0, i = 0;
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char *addr = area;
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if (g_once_init_enter(&initialized)) {
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qemu_mutex_init(&page_mutex);
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qemu_cond_init(&page_cond);
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g_once_init_leave(&initialized, 1);
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}
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if (use_madv_populate_write) {
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/* Avoid creating a single thread for MADV_POPULATE_WRITE */
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if (context.num_threads == 1) {
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if (qemu_madvise(area, hpagesize * numpages,
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QEMU_MADV_POPULATE_WRITE)) {
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return -errno;
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}
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return 0;
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}
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touch_fn = do_madv_populate_write_pages;
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} else {
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touch_fn = do_touch_pages;
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}
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context.threads = g_new0(MemsetThread, context.num_threads);
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numpages_per_thread = numpages / context.num_threads;
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leftover = numpages % context.num_threads;
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for (i = 0; i < context.num_threads; i++) {
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context.threads[i].addr = addr;
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context.threads[i].numpages = numpages_per_thread + (i < leftover);
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context.threads[i].hpagesize = hpagesize;
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context.threads[i].context = &context;
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qemu_thread_create(&context.threads[i].pgthread, "touch_pages",
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touch_fn, &context.threads[i],
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QEMU_THREAD_JOINABLE);
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addr += context.threads[i].numpages * hpagesize;
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}
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if (!use_madv_populate_write) {
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sigbus_memset_context = &context;
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}
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qemu_mutex_lock(&page_mutex);
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context.all_threads_created = true;
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qemu_cond_broadcast(&page_cond);
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qemu_mutex_unlock(&page_mutex);
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for (i = 0; i < context.num_threads; i++) {
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int tmp = (uintptr_t)qemu_thread_join(&context.threads[i].pgthread);
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if (tmp) {
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ret = tmp;
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}
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}
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if (!use_madv_populate_write) {
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sigbus_memset_context = NULL;
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}
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g_free(context.threads);
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return ret;
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}
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static bool madv_populate_write_possible(char *area, size_t pagesize)
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{
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return !qemu_madvise(area, pagesize, QEMU_MADV_POPULATE_WRITE) ||
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errno != EINVAL;
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}
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void os_mem_prealloc(int fd, char *area, size_t memory, int smp_cpus,
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Error **errp)
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{
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static gsize initialized;
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int ret;
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size_t hpagesize = qemu_fd_getpagesize(fd);
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size_t numpages = DIV_ROUND_UP(memory, hpagesize);
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bool use_madv_populate_write;
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struct sigaction act;
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/*
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* Sense on every invocation, as MADV_POPULATE_WRITE cannot be used for
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* some special mappings, such as mapping /dev/mem.
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*/
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use_madv_populate_write = madv_populate_write_possible(area, hpagesize);
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if (!use_madv_populate_write) {
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if (g_once_init_enter(&initialized)) {
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qemu_mutex_init(&sigbus_mutex);
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g_once_init_leave(&initialized, 1);
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}
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qemu_mutex_lock(&sigbus_mutex);
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memset(&act, 0, sizeof(act));
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#ifdef CONFIG_LINUX
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act.sa_sigaction = &sigbus_handler;
|
|
act.sa_flags = SA_SIGINFO;
|
|
#else /* CONFIG_LINUX */
|
|
act.sa_handler = &sigbus_handler;
|
|
act.sa_flags = 0;
|
|
#endif /* CONFIG_LINUX */
|
|
|
|
ret = sigaction(SIGBUS, &act, &sigbus_oldact);
|
|
if (ret) {
|
|
qemu_mutex_unlock(&sigbus_mutex);
|
|
error_setg_errno(errp, errno,
|
|
"os_mem_prealloc: failed to install signal handler");
|
|
return;
|
|
}
|
|
}
|
|
|
|
/* touch pages simultaneously */
|
|
ret = touch_all_pages(area, hpagesize, numpages, smp_cpus,
|
|
use_madv_populate_write);
|
|
if (ret) {
|
|
error_setg_errno(errp, -ret,
|
|
"os_mem_prealloc: preallocating memory failed");
|
|
}
|
|
|
|
if (!use_madv_populate_write) {
|
|
ret = sigaction(SIGBUS, &sigbus_oldact, NULL);
|
|
if (ret) {
|
|
/* Terminate QEMU since it can't recover from error */
|
|
perror("os_mem_prealloc: failed to reinstall signal handler");
|
|
exit(1);
|
|
}
|
|
qemu_mutex_unlock(&sigbus_mutex);
|
|
}
|
|
}
|
|
|
|
char *qemu_get_pid_name(pid_t pid)
|
|
{
|
|
char *name = NULL;
|
|
|
|
#if defined(__FreeBSD__)
|
|
/* BSDs don't have /proc, but they provide a nice substitute */
|
|
struct kinfo_proc *proc = kinfo_getproc(pid);
|
|
|
|
if (proc) {
|
|
name = g_strdup(proc->ki_comm);
|
|
free(proc);
|
|
}
|
|
#else
|
|
/* Assume a system with reasonable procfs */
|
|
char *pid_path;
|
|
size_t len;
|
|
|
|
pid_path = g_strdup_printf("/proc/%d/cmdline", pid);
|
|
g_file_get_contents(pid_path, &name, &len, NULL);
|
|
g_free(pid_path);
|
|
#endif
|
|
|
|
return name;
|
|
}
|
|
|
|
|
|
pid_t qemu_fork(Error **errp)
|
|
{
|
|
sigset_t oldmask, newmask;
|
|
struct sigaction sig_action;
|
|
int saved_errno;
|
|
pid_t pid;
|
|
|
|
/*
|
|
* Need to block signals now, so that child process can safely
|
|
* kill off caller's signal handlers without a race.
|
|
*/
|
|
sigfillset(&newmask);
|
|
if (pthread_sigmask(SIG_SETMASK, &newmask, &oldmask) != 0) {
|
|
error_setg_errno(errp, errno,
|
|
"cannot block signals");
|
|
return -1;
|
|
}
|
|
|
|
pid = fork();
|
|
saved_errno = errno;
|
|
|
|
if (pid < 0) {
|
|
/* attempt to restore signal mask, but ignore failure, to
|
|
* avoid obscuring the fork failure */
|
|
(void)pthread_sigmask(SIG_SETMASK, &oldmask, NULL);
|
|
error_setg_errno(errp, saved_errno,
|
|
"cannot fork child process");
|
|
errno = saved_errno;
|
|
return -1;
|
|
} else if (pid) {
|
|
/* parent process */
|
|
|
|
/* Restore our original signal mask now that the child is
|
|
* safely running. Only documented failures are EFAULT (not
|
|
* possible, since we are using just-grabbed mask) or EINVAL
|
|
* (not possible, since we are using correct arguments). */
|
|
(void)pthread_sigmask(SIG_SETMASK, &oldmask, NULL);
|
|
} else {
|
|
/* child process */
|
|
size_t i;
|
|
|
|
/* Clear out all signal handlers from parent so nothing
|
|
* unexpected can happen in our child once we unblock
|
|
* signals */
|
|
sig_action.sa_handler = SIG_DFL;
|
|
sig_action.sa_flags = 0;
|
|
sigemptyset(&sig_action.sa_mask);
|
|
|
|
for (i = 1; i < NSIG; i++) {
|
|
/* Only possible errors are EFAULT or EINVAL The former
|
|
* won't happen, the latter we expect, so no need to check
|
|
* return value */
|
|
(void)sigaction(i, &sig_action, NULL);
|
|
}
|
|
|
|
/* Unmask all signals in child, since we've no idea what the
|
|
* caller's done with their signal mask and don't want to
|
|
* propagate that to children */
|
|
sigemptyset(&newmask);
|
|
if (pthread_sigmask(SIG_SETMASK, &newmask, NULL) != 0) {
|
|
Error *local_err = NULL;
|
|
error_setg_errno(&local_err, errno,
|
|
"cannot unblock signals");
|
|
error_report_err(local_err);
|
|
_exit(1);
|
|
}
|
|
}
|
|
return pid;
|
|
}
|
|
|
|
void *qemu_alloc_stack(size_t *sz)
|
|
{
|
|
void *ptr, *guardpage;
|
|
int flags;
|
|
#ifdef CONFIG_DEBUG_STACK_USAGE
|
|
void *ptr2;
|
|
#endif
|
|
size_t pagesz = qemu_real_host_page_size();
|
|
#ifdef _SC_THREAD_STACK_MIN
|
|
/* avoid stacks smaller than _SC_THREAD_STACK_MIN */
|
|
long min_stack_sz = sysconf(_SC_THREAD_STACK_MIN);
|
|
*sz = MAX(MAX(min_stack_sz, 0), *sz);
|
|
#endif
|
|
/* adjust stack size to a multiple of the page size */
|
|
*sz = ROUND_UP(*sz, pagesz);
|
|
/* allocate one extra page for the guard page */
|
|
*sz += pagesz;
|
|
|
|
flags = MAP_PRIVATE | MAP_ANONYMOUS;
|
|
#if defined(MAP_STACK) && defined(__OpenBSD__)
|
|
/* Only enable MAP_STACK on OpenBSD. Other OS's such as
|
|
* Linux/FreeBSD/NetBSD have a flag with the same name
|
|
* but have differing functionality. OpenBSD will SEGV
|
|
* if it spots execution with a stack pointer pointing
|
|
* at memory that was not allocated with MAP_STACK.
|
|
*/
|
|
flags |= MAP_STACK;
|
|
#endif
|
|
|
|
ptr = mmap(NULL, *sz, PROT_READ | PROT_WRITE, flags, -1, 0);
|
|
if (ptr == MAP_FAILED) {
|
|
perror("failed to allocate memory for stack");
|
|
abort();
|
|
}
|
|
|
|
#if defined(HOST_IA64)
|
|
/* separate register stack */
|
|
guardpage = ptr + (((*sz - pagesz) / 2) & ~pagesz);
|
|
#elif defined(HOST_HPPA)
|
|
/* stack grows up */
|
|
guardpage = ptr + *sz - pagesz;
|
|
#else
|
|
/* stack grows down */
|
|
guardpage = ptr;
|
|
#endif
|
|
if (mprotect(guardpage, pagesz, PROT_NONE) != 0) {
|
|
perror("failed to set up stack guard page");
|
|
abort();
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_STACK_USAGE
|
|
for (ptr2 = ptr + pagesz; ptr2 < ptr + *sz; ptr2 += sizeof(uint32_t)) {
|
|
*(uint32_t *)ptr2 = 0xdeadbeaf;
|
|
}
|
|
#endif
|
|
|
|
return ptr;
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_STACK_USAGE
|
|
static __thread unsigned int max_stack_usage;
|
|
#endif
|
|
|
|
void qemu_free_stack(void *stack, size_t sz)
|
|
{
|
|
#ifdef CONFIG_DEBUG_STACK_USAGE
|
|
unsigned int usage;
|
|
void *ptr;
|
|
|
|
for (ptr = stack + qemu_real_host_page_size(); ptr < stack + sz;
|
|
ptr += sizeof(uint32_t)) {
|
|
if (*(uint32_t *)ptr != 0xdeadbeaf) {
|
|
break;
|
|
}
|
|
}
|
|
usage = sz - (uintptr_t) (ptr - stack);
|
|
if (usage > max_stack_usage) {
|
|
error_report("thread %d max stack usage increased from %u to %u",
|
|
qemu_get_thread_id(), max_stack_usage, usage);
|
|
max_stack_usage = usage;
|
|
}
|
|
#endif
|
|
|
|
munmap(stack, sz);
|
|
}
|
|
|
|
/*
|
|
* Disable CFI checks.
|
|
* We are going to call a signal hander directly. Such handler may or may not
|
|
* have been defined in our binary, so there's no guarantee that the pointer
|
|
* used to set the handler is a cfi-valid pointer. Since the handlers are
|
|
* stored in kernel memory, changing the handler to an attacker-defined
|
|
* function requires being able to call a sigaction() syscall,
|
|
* which is not as easy as overwriting a pointer in memory.
|
|
*/
|
|
QEMU_DISABLE_CFI
|
|
void sigaction_invoke(struct sigaction *action,
|
|
struct qemu_signalfd_siginfo *info)
|
|
{
|
|
siginfo_t si = {};
|
|
si.si_signo = info->ssi_signo;
|
|
si.si_errno = info->ssi_errno;
|
|
si.si_code = info->ssi_code;
|
|
|
|
/* Convert the minimal set of fields defined by POSIX.
|
|
* Positive si_code values are reserved for kernel-generated
|
|
* signals, where the valid siginfo fields are determined by
|
|
* the signal number. But according to POSIX, it is unspecified
|
|
* whether SI_USER and SI_QUEUE have values less than or equal to
|
|
* zero.
|
|
*/
|
|
if (info->ssi_code == SI_USER || info->ssi_code == SI_QUEUE ||
|
|
info->ssi_code <= 0) {
|
|
/* SIGTERM, etc. */
|
|
si.si_pid = info->ssi_pid;
|
|
si.si_uid = info->ssi_uid;
|
|
} else if (info->ssi_signo == SIGILL || info->ssi_signo == SIGFPE ||
|
|
info->ssi_signo == SIGSEGV || info->ssi_signo == SIGBUS) {
|
|
si.si_addr = (void *)(uintptr_t)info->ssi_addr;
|
|
} else if (info->ssi_signo == SIGCHLD) {
|
|
si.si_pid = info->ssi_pid;
|
|
si.si_status = info->ssi_status;
|
|
si.si_uid = info->ssi_uid;
|
|
}
|
|
action->sa_sigaction(info->ssi_signo, &si, NULL);
|
|
}
|
|
|
|
size_t qemu_get_host_physmem(void)
|
|
{
|
|
#ifdef _SC_PHYS_PAGES
|
|
long pages = sysconf(_SC_PHYS_PAGES);
|
|
if (pages > 0) {
|
|
if (pages > SIZE_MAX / qemu_real_host_page_size()) {
|
|
return SIZE_MAX;
|
|
} else {
|
|
return pages * qemu_real_host_page_size();
|
|
}
|
|
}
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
int qemu_msync(void *addr, size_t length, int fd)
|
|
{
|
|
size_t align_mask = ~(qemu_real_host_page_size() - 1);
|
|
|
|
/**
|
|
* There are no strict reqs as per the length of mapping
|
|
* to be synced. Still the length needs to follow the address
|
|
* alignment changes. Additionally - round the size to the multiple
|
|
* of PAGE_SIZE
|
|
*/
|
|
length += ((uintptr_t)addr & (qemu_real_host_page_size() - 1));
|
|
length = (length + ~align_mask) & align_mask;
|
|
|
|
addr = (void *)((uintptr_t)addr & align_mask);
|
|
|
|
return msync(addr, length, MS_SYNC);
|
|
}
|