qemu/bsd-user/main.c
Warner Losh be04f210f9 bsd-user: Update mapping to handle reserved and starting conditions
Update the reserved base based on what platform we're on, as well as the
start of the mmap range. Update routines that find va ranges to interact
with the reserved ranges as well as properly align the mapping (this is
especially important for targets whose page size does not match the
host's). Loop where appropriate when the initial address space offered
by mmap does not meet the contraints.

This has 18e80c55bb from linux-user folded in to the upstream
bsd-user code as well.

Signed-off-by: Mikaël Urankar <mikael.urankar@gmail.com>
Signed-off-by: Stacey Son <sson@FreeBSD.org>
Signed-off-by: Warner Losh <imp@bsdimp.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Kyle Evans <kevans@FreeBSD.org>
2021-09-10 14:13:06 -06:00

559 lines
16 KiB
C

/*
* qemu bsd user main
*
* Copyright (c) 2003-2008 Fabrice Bellard
* Copyright (c) 2013-14 Stacey Son
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/sysctl.h>
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "qemu/units.h"
#include "qemu/accel.h"
#include "sysemu/tcg.h"
#include "qemu-version.h"
#include <machine/trap.h>
#include "qapi/error.h"
#include "qemu.h"
#include "qemu/config-file.h"
#include "qemu/error-report.h"
#include "qemu/path.h"
#include "qemu/help_option.h"
#include "qemu/module.h"
#include "exec/exec-all.h"
#include "tcg/tcg.h"
#include "qemu/timer.h"
#include "qemu/envlist.h"
#include "qemu/cutils.h"
#include "exec/log.h"
#include "trace/control.h"
#include "crypto/init.h"
#include "qemu/guest-random.h"
#include "host-os.h"
#include "target_arch_cpu.h"
int singlestep;
uintptr_t guest_base;
bool have_guest_base;
/*
* When running 32-on-64 we should make sure we can fit all of the possible
* guest address space into a contiguous chunk of virtual host memory.
*
* This way we will never overlap with our own libraries or binaries or stack
* or anything else that QEMU maps.
*
* Many cpus reserve the high bit (or more than one for some 64-bit cpus)
* of the address for the kernel. Some cpus rely on this and user space
* uses the high bit(s) for pointer tagging and the like. For them, we
* must preserve the expected address space.
*/
#ifndef MAX_RESERVED_VA
# if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
# if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \
(TARGET_LONG_BITS == 32 || defined(TARGET_ABI32))
/*
* There are a number of places where we assign reserved_va to a variable
* of type abi_ulong and expect it to fit. Avoid the last page.
*/
# define MAX_RESERVED_VA (0xfffffffful & TARGET_PAGE_MASK)
# else
# define MAX_RESERVED_VA (1ul << TARGET_VIRT_ADDR_SPACE_BITS)
# endif
# else
# define MAX_RESERVED_VA 0
# endif
#endif
/*
* That said, reserving *too* much vm space via mmap can run into problems
* with rlimits, oom due to page table creation, etc. We will still try it,
* if directed by the command-line option, but not by default.
*/
#if HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32
unsigned long reserved_va = MAX_RESERVED_VA;
#else
unsigned long reserved_va;
#endif
static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
const char *qemu_uname_release;
enum BSDType bsd_type;
char qemu_proc_pathname[PATH_MAX]; /* full path to exeutable */
unsigned long target_maxtsiz = TARGET_MAXTSIZ; /* max text size */
unsigned long target_dfldsiz = TARGET_DFLDSIZ; /* initial data size limit */
unsigned long target_maxdsiz = TARGET_MAXDSIZ; /* max data size */
unsigned long target_dflssiz = TARGET_DFLSSIZ; /* initial data size limit */
unsigned long target_maxssiz = TARGET_MAXSSIZ; /* max stack size */
unsigned long target_sgrowsiz = TARGET_SGROWSIZ; /* amount to grow stack */
/* Helper routines for implementing atomic operations. */
void fork_start(void)
{
start_exclusive();
cpu_list_lock();
mmap_fork_start();
}
void fork_end(int child)
{
if (child) {
CPUState *cpu, *next_cpu;
/*
* Child processes created by fork() only have a single thread. Discard
* information about the parent threads.
*/
CPU_FOREACH_SAFE(cpu, next_cpu) {
if (cpu != thread_cpu) {
QTAILQ_REMOVE_RCU(&cpus, cpu, node);
}
}
mmap_fork_end(child);
/*
* qemu_init_cpu_list() takes care of reinitializing the exclusive
* state, so we don't need to end_exclusive() here.
*/
qemu_init_cpu_list();
gdbserver_fork(thread_cpu);
} else {
mmap_fork_end(child);
cpu_list_unlock();
end_exclusive();
}
}
void cpu_loop(CPUArchState *env)
{
target_cpu_loop(env);
}
static void usage(void)
{
printf("qemu-" TARGET_NAME " version " QEMU_FULL_VERSION
"\n" QEMU_COPYRIGHT "\n"
"usage: qemu-" TARGET_NAME " [options] program [arguments...]\n"
"BSD CPU emulator (compiled for %s emulation)\n"
"\n"
"Standard options:\n"
"-h print this help\n"
"-g port wait gdb connection to port\n"
"-L path set the elf interpreter prefix (default=%s)\n"
"-s size set the stack size in bytes (default=%ld)\n"
"-cpu model select CPU (-cpu help for list)\n"
"-drop-ld-preload drop LD_PRELOAD for target process\n"
"-E var=value sets/modifies targets environment variable(s)\n"
"-U var unsets targets environment variable(s)\n"
"-B address set guest_base address to address\n"
"-bsd type select emulated BSD type FreeBSD/NetBSD/OpenBSD (default)\n"
"\n"
"Debug options:\n"
"-d item1[,...] enable logging of specified items\n"
" (use '-d help' for a list of log items)\n"
"-D logfile write logs to 'logfile' (default stderr)\n"
"-singlestep always run in singlestep mode\n"
"-strace log system calls\n"
"-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
" specify tracing options\n"
"\n"
"Environment variables:\n"
"QEMU_STRACE Print system calls and arguments similar to the\n"
" 'strace' program. Enable by setting to any value.\n"
"You can use -E and -U options to set/unset environment variables\n"
"for target process. It is possible to provide several variables\n"
"by repeating the option. For example:\n"
" -E var1=val2 -E var2=val2 -U LD_PRELOAD -U LD_DEBUG\n"
"Note that if you provide several changes to single variable\n"
"last change will stay in effect.\n"
"\n"
QEMU_HELP_BOTTOM "\n"
,
TARGET_NAME,
interp_prefix,
target_dflssiz);
exit(1);
}
__thread CPUState *thread_cpu;
bool qemu_cpu_is_self(CPUState *cpu)
{
return thread_cpu == cpu;
}
void qemu_cpu_kick(CPUState *cpu)
{
cpu_exit(cpu);
}
/* Assumes contents are already zeroed. */
void init_task_state(TaskState *ts)
{
int i;
ts->used = 1;
ts->first_free = ts->sigqueue_table;
for (i = 0; i < MAX_SIGQUEUE_SIZE - 1; i++) {
ts->sigqueue_table[i].next = &ts->sigqueue_table[i + 1];
}
ts->sigqueue_table[i].next = NULL;
}
void gemu_log(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
}
static void
adjust_ssize(void)
{
struct rlimit rl;
if (getrlimit(RLIMIT_STACK, &rl) != 0) {
return;
}
target_maxssiz = MIN(target_maxssiz, rl.rlim_max);
target_dflssiz = MIN(MAX(target_dflssiz, rl.rlim_cur), target_maxssiz);
rl.rlim_max = target_maxssiz;
rl.rlim_cur = target_dflssiz;
setrlimit(RLIMIT_STACK, &rl);
}
static void save_proc_pathname(char *argv0)
{
int mib[4];
size_t len;
mib[0] = CTL_KERN;
mib[1] = KERN_PROC;
mib[2] = KERN_PROC_PATHNAME;
mib[3] = -1;
len = sizeof(qemu_proc_pathname);
if (sysctl(mib, 4, qemu_proc_pathname, &len, NULL, 0)) {
perror("sysctl");
}
}
int main(int argc, char **argv)
{
const char *filename;
const char *cpu_model;
const char *cpu_type;
const char *log_file = NULL;
const char *log_mask = NULL;
const char *seed_optarg = NULL;
struct target_pt_regs regs1, *regs = &regs1;
struct image_info info1, *info = &info1;
struct bsd_binprm bprm;
TaskState *ts;
CPUArchState *env;
CPUState *cpu;
int optind, rv;
const char *r;
const char *gdbstub = NULL;
char **target_environ, **wrk;
envlist_t *envlist = NULL;
bsd_type = HOST_DEFAULT_BSD_TYPE;
char *argv0 = NULL;
adjust_ssize();
if (argc <= 1) {
usage();
}
save_proc_pathname(argv[0]);
error_init(argv[0]);
module_call_init(MODULE_INIT_TRACE);
qemu_init_cpu_list();
module_call_init(MODULE_INIT_QOM);
envlist = envlist_create();
/* add current environment into the list */
for (wrk = environ; *wrk != NULL; wrk++) {
(void) envlist_setenv(envlist, *wrk);
}
cpu_model = NULL;
qemu_add_opts(&qemu_trace_opts);
optind = 1;
for (;;) {
if (optind >= argc) {
break;
}
r = argv[optind];
if (r[0] != '-') {
break;
}
optind++;
r++;
if (!strcmp(r, "-")) {
break;
} else if (!strcmp(r, "d")) {
if (optind >= argc) {
break;
}
log_mask = argv[optind++];
} else if (!strcmp(r, "D")) {
if (optind >= argc) {
break;
}
log_file = argv[optind++];
} else if (!strcmp(r, "E")) {
r = argv[optind++];
if (envlist_setenv(envlist, r) != 0) {
usage();
}
} else if (!strcmp(r, "ignore-environment")) {
envlist_free(envlist);
envlist = envlist_create();
} else if (!strcmp(r, "U")) {
r = argv[optind++];
if (envlist_unsetenv(envlist, r) != 0) {
usage();
}
} else if (!strcmp(r, "s")) {
r = argv[optind++];
rv = qemu_strtoul(r, &r, 0, &target_dflssiz);
if (rv < 0 || target_dflssiz <= 0) {
usage();
}
if (*r == 'M') {
target_dflssiz *= 1024 * 1024;
} else if (*r == 'k' || *r == 'K') {
target_dflssiz *= 1024;
}
if (target_dflssiz > target_maxssiz) {
usage();
}
} else if (!strcmp(r, "L")) {
interp_prefix = argv[optind++];
} else if (!strcmp(r, "p")) {
qemu_host_page_size = atoi(argv[optind++]);
if (qemu_host_page_size == 0 ||
(qemu_host_page_size & (qemu_host_page_size - 1)) != 0) {
fprintf(stderr, "page size must be a power of two\n");
exit(1);
}
} else if (!strcmp(r, "g")) {
gdbstub = g_strdup(argv[optind++]);
} else if (!strcmp(r, "r")) {
qemu_uname_release = argv[optind++];
} else if (!strcmp(r, "cpu")) {
cpu_model = argv[optind++];
if (is_help_option(cpu_model)) {
/* XXX: implement xxx_cpu_list for targets that still miss it */
#if defined(cpu_list)
cpu_list();
#endif
exit(1);
}
} else if (!strcmp(r, "B")) {
rv = qemu_strtoul(argv[optind++], NULL, 0, &guest_base);
if (rv < 0) {
usage();
}
have_guest_base = true;
} else if (!strcmp(r, "drop-ld-preload")) {
(void) envlist_unsetenv(envlist, "LD_PRELOAD");
} else if (!strcmp(r, "bsd")) {
if (!strcasecmp(argv[optind], "freebsd")) {
bsd_type = target_freebsd;
} else if (!strcasecmp(argv[optind], "netbsd")) {
bsd_type = target_netbsd;
} else if (!strcasecmp(argv[optind], "openbsd")) {
bsd_type = target_openbsd;
} else {
usage();
}
optind++;
} else if (!strcmp(r, "seed")) {
seed_optarg = optarg;
} else if (!strcmp(r, "singlestep")) {
singlestep = 1;
} else if (!strcmp(r, "strace")) {
do_strace = 1;
} else if (!strcmp(r, "trace")) {
trace_opt_parse(optarg);
} else if (!strcmp(r, "0")) {
argv0 = argv[optind++];
} else {
usage();
}
}
/* init debug */
qemu_log_needs_buffers();
qemu_set_log_filename(log_file, &error_fatal);
if (log_mask) {
int mask;
mask = qemu_str_to_log_mask(log_mask);
if (!mask) {
qemu_print_log_usage(stdout);
exit(1);
}
qemu_set_log(mask);
}
if (optind >= argc) {
usage();
}
filename = argv[optind];
if (argv0) {
argv[optind] = argv0;
}
if (!trace_init_backends()) {
exit(1);
}
trace_init_file();
/* Zero out regs */
memset(regs, 0, sizeof(struct target_pt_regs));
/* Zero bsd params */
memset(&bprm, 0, sizeof(bprm));
/* Zero out image_info */
memset(info, 0, sizeof(struct image_info));
/* Scan interp_prefix dir for replacement files. */
init_paths(interp_prefix);
if (cpu_model == NULL) {
cpu_model = TARGET_DEFAULT_CPU_MODEL;
}
cpu_type = parse_cpu_option(cpu_model);
/* init tcg before creating CPUs and to get qemu_host_page_size */
{
AccelClass *ac = ACCEL_GET_CLASS(current_accel());
accel_init_interfaces(ac);
ac->init_machine(NULL);
}
cpu = cpu_create(cpu_type);
env = cpu->env_ptr;
cpu_reset(cpu);
thread_cpu = cpu;
if (getenv("QEMU_STRACE")) {
do_strace = 1;
}
target_environ = envlist_to_environ(envlist, NULL);
envlist_free(envlist);
if (reserved_va) {
mmap_next_start = reserved_va;
}
{
Error *err = NULL;
if (seed_optarg != NULL) {
qemu_guest_random_seed_main(seed_optarg, &err);
} else {
qcrypto_init(&err);
}
if (err) {
error_reportf_err(err, "cannot initialize crypto: ");
exit(1);
}
}
/*
* Now that page sizes are configured we can do
* proper page alignment for guest_base.
*/
guest_base = HOST_PAGE_ALIGN(guest_base);
if (loader_exec(filename, argv + optind, target_environ, regs, info,
&bprm) != 0) {
printf("Error loading %s\n", filename);
_exit(1);
}
for (wrk = target_environ; *wrk; wrk++) {
g_free(*wrk);
}
g_free(target_environ);
if (qemu_loglevel_mask(CPU_LOG_PAGE)) {
qemu_log("guest_base %p\n", (void *)guest_base);
log_page_dump("binary load");
qemu_log("start_brk 0x" TARGET_ABI_FMT_lx "\n", info->start_brk);
qemu_log("end_code 0x" TARGET_ABI_FMT_lx "\n", info->end_code);
qemu_log("start_code 0x" TARGET_ABI_FMT_lx "\n",
info->start_code);
qemu_log("start_data 0x" TARGET_ABI_FMT_lx "\n",
info->start_data);
qemu_log("end_data 0x" TARGET_ABI_FMT_lx "\n", info->end_data);
qemu_log("start_stack 0x" TARGET_ABI_FMT_lx "\n",
info->start_stack);
qemu_log("brk 0x" TARGET_ABI_FMT_lx "\n", info->brk);
qemu_log("entry 0x" TARGET_ABI_FMT_lx "\n", info->entry);
}
/* build Task State */
ts = g_new0(TaskState, 1);
init_task_state(ts);
ts->info = info;
ts->bprm = &bprm;
cpu->opaque = ts;
target_set_brk(info->brk);
syscall_init();
signal_init();
/*
* Now that we've loaded the binary, GUEST_BASE is fixed. Delay
* generating the prologue until now so that the prologue can take
* the real value of GUEST_BASE into account.
*/
tcg_prologue_init(tcg_ctx);
target_cpu_init(env, regs);
if (gdbstub) {
gdbserver_start(gdbstub);
gdb_handlesig(cpu, 0);
}
cpu_loop(env);
/* never exits */
return 0;
}