qemu/qemu-io.c
Stefan Hajnoczi b49f4755c7 block: remove AioContext locking
This is the big patch that removes
aio_context_acquire()/aio_context_release() from the block layer and
affected block layer users.

There isn't a clean way to split this patch and the reviewers are likely
the same group of people, so I decided to do it in one patch.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Message-ID: <20231205182011.1976568-7-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-12-21 22:49:27 +01:00

689 lines
18 KiB
C

/*
* Command line utility to exercise the QEMU I/O path.
*
* Copyright (C) 2009 Red Hat, Inc.
* Copyright (c) 2003-2005 Silicon Graphics, Inc.
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include <getopt.h>
#include <libgen.h>
#ifndef _WIN32
#include <termios.h>
#endif
#include "qemu/help-texts.h"
#include "qemu/cutils.h"
#include "qapi/error.h"
#include "qemu-io.h"
#include "qemu/error-report.h"
#include "qemu/main-loop.h"
#include "qemu/module.h"
#include "qemu/option.h"
#include "qemu/config-file.h"
#include "qemu/readline.h"
#include "qemu/log.h"
#include "qemu/sockets.h"
#include "qapi/qmp/qstring.h"
#include "qapi/qmp/qdict.h"
#include "qom/object_interfaces.h"
#include "sysemu/block-backend.h"
#include "block/block_int.h"
#include "trace/control.h"
#include "crypto/init.h"
#include "qemu-version.h"
#define CMD_NOFILE_OK 0x01
static BlockBackend *qemuio_blk;
static bool quit_qemu_io;
/* qemu-io commands passed using -c */
static int ncmdline;
static char **cmdline;
static bool imageOpts;
static ReadLineState *readline_state;
static int ttyEOF;
static int get_eof_char(void)
{
#ifdef _WIN32
return 0x4; /* Ctrl-D */
#else
struct termios tty;
if (tcgetattr(STDIN_FILENO, &tty) != 0) {
if (errno == ENOTTY) {
return 0x0; /* just expect read() == 0 */
} else {
return 0x4; /* Ctrl-D */
}
}
return tty.c_cc[VEOF];
#endif
}
static int close_f(BlockBackend *blk, int argc, char **argv)
{
blk_unref(qemuio_blk);
qemuio_blk = NULL;
return 0;
}
static const cmdinfo_t close_cmd = {
.name = "close",
.altname = "c",
.cfunc = close_f,
.oneline = "close the current open file",
};
static int openfile(char *name, int flags, bool writethrough, bool force_share,
QDict *opts)
{
Error *local_err = NULL;
if (qemuio_blk) {
error_report("file open already, try 'help close'");
qobject_unref(opts);
return 1;
}
if (force_share) {
if (!opts) {
opts = qdict_new();
}
if (qdict_haskey(opts, BDRV_OPT_FORCE_SHARE)
&& strcmp(qdict_get_str(opts, BDRV_OPT_FORCE_SHARE), "on")) {
error_report("-U conflicts with image options");
qobject_unref(opts);
return 1;
}
qdict_put_str(opts, BDRV_OPT_FORCE_SHARE, "on");
}
qemuio_blk = blk_new_open(name, NULL, opts, flags, &local_err);
if (!qemuio_blk) {
error_reportf_err(local_err, "can't open%s%s: ",
name ? " device " : "", name ?: "");
return 1;
}
blk_set_enable_write_cache(qemuio_blk, !writethrough);
return 0;
}
static void open_help(void)
{
printf(
"\n"
" opens a new file in the requested mode\n"
"\n"
" Example:\n"
" 'open -n -o driver=raw /tmp/data' - opens raw data file read-write, uncached\n"
"\n"
" Opens a file for subsequent use by all of the other qemu-io commands.\n"
" -r, -- open file read-only\n"
" -s, -- use snapshot file\n"
" -C, -- use copy-on-read\n"
" -n, -- disable host cache, short for -t none\n"
" -U, -- force shared permissions\n"
" -k, -- use kernel AIO implementation (Linux only, prefer use of -i)\n"
" -i, -- use AIO mode (threads, native or io_uring)\n"
" -t, -- use the given cache mode for the image\n"
" -d, -- use the given discard mode for the image\n"
" -o, -- options to be given to the block driver"
"\n");
}
static int open_f(BlockBackend *blk, int argc, char **argv);
static const cmdinfo_t open_cmd = {
.name = "open",
.altname = "o",
.cfunc = open_f,
.argmin = 1,
.argmax = -1,
.flags = CMD_NOFILE_OK,
.args = "[-rsCnkU] [-t cache] [-d discard] [-o options] [path]",
.oneline = "open the file specified by path",
.help = open_help,
};
static QemuOptsList empty_opts = {
.name = "drive",
.merge_lists = true,
.head = QTAILQ_HEAD_INITIALIZER(empty_opts.head),
.desc = {
/* no elements => accept any params */
{ /* end of list */ }
},
};
static int open_f(BlockBackend *blk, int argc, char **argv)
{
int flags = BDRV_O_UNMAP;
int readonly = 0;
bool writethrough = true;
int c;
int ret;
QemuOpts *qopts;
QDict *opts;
bool force_share = false;
while ((c = getopt(argc, argv, "snCro:ki:t:d:U")) != -1) {
switch (c) {
case 's':
flags |= BDRV_O_SNAPSHOT;
break;
case 'n':
flags |= BDRV_O_NOCACHE;
writethrough = false;
break;
case 'C':
flags |= BDRV_O_COPY_ON_READ;
break;
case 'r':
readonly = 1;
break;
case 'k':
flags |= BDRV_O_NATIVE_AIO;
break;
case 't':
if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) < 0) {
error_report("Invalid cache option: %s", optarg);
qemu_opts_reset(&empty_opts);
return -EINVAL;
}
break;
case 'd':
if (bdrv_parse_discard_flags(optarg, &flags) < 0) {
error_report("Invalid discard option: %s", optarg);
qemu_opts_reset(&empty_opts);
return -EINVAL;
}
break;
case 'i':
if (bdrv_parse_aio(optarg, &flags) < 0) {
error_report("Invalid aio option: %s", optarg);
qemu_opts_reset(&empty_opts);
return -EINVAL;
}
break;
case 'o':
if (imageOpts) {
printf("--image-opts and 'open -o' are mutually exclusive\n");
qemu_opts_reset(&empty_opts);
return -EINVAL;
}
if (!qemu_opts_parse_noisily(&empty_opts, optarg, false)) {
qemu_opts_reset(&empty_opts);
return -EINVAL;
}
break;
case 'U':
force_share = true;
break;
default:
qemu_opts_reset(&empty_opts);
qemuio_command_usage(&open_cmd);
return -EINVAL;
}
}
if (!readonly) {
flags |= BDRV_O_RDWR;
}
if (imageOpts && (optind == argc - 1)) {
if (!qemu_opts_parse_noisily(&empty_opts, argv[optind], false)) {
qemu_opts_reset(&empty_opts);
return -EINVAL;
}
optind++;
}
qopts = qemu_opts_find(&empty_opts, NULL);
opts = qopts ? qemu_opts_to_qdict(qopts, NULL) : NULL;
qemu_opts_reset(&empty_opts);
if (optind == argc - 1) {
ret = openfile(argv[optind], flags, writethrough, force_share, opts);
} else if (optind == argc) {
ret = openfile(NULL, flags, writethrough, force_share, opts);
} else {
qobject_unref(opts);
qemuio_command_usage(&open_cmd);
return -EINVAL;
}
if (ret) {
return -EINVAL;
}
return 0;
}
static int quit_f(BlockBackend *blk, int argc, char **argv)
{
quit_qemu_io = true;
return 0;
}
static const cmdinfo_t quit_cmd = {
.name = "quit",
.altname = "q",
.cfunc = quit_f,
.argmin = -1,
.argmax = -1,
.flags = CMD_FLAG_GLOBAL,
.oneline = "exit the program",
};
static void usage(const char *name)
{
printf(
"Usage: %s [OPTIONS]... [-c STRING]... [file]\n"
"QEMU Disk exerciser\n"
"\n"
" --object OBJECTDEF define an object such as 'secret' for\n"
" passwords and/or encryption keys\n"
" --image-opts treat file as option string\n"
" -c, --cmd STRING execute command with its arguments\n"
" from the given string\n"
" -f, --format FMT specifies the block driver to use\n"
" -r, --read-only export read-only\n"
" -s, --snapshot use snapshot file\n"
" -n, --nocache disable host cache, short for -t none\n"
" -C, --copy-on-read enable copy-on-read\n"
" -m, --misalign misalign allocations for O_DIRECT\n"
" -k, --native-aio use kernel AIO implementation\n"
" (Linux only, prefer use of -i)\n"
" -i, --aio=MODE use AIO mode (threads, native or io_uring)\n"
" -t, --cache=MODE use the given cache mode for the image\n"
" -d, --discard=MODE use the given discard mode for the image\n"
" -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
" specify tracing options\n"
" see qemu-img(1) man page for full description\n"
" -U, --force-share force shared permissions\n"
" -h, --help display this help and exit\n"
" -V, --version output version information and exit\n"
"\n"
"See '%s -c help' for information on available commands.\n"
"\n"
QEMU_HELP_BOTTOM "\n",
name, name);
}
static char *get_prompt(void)
{
static char prompt[FILENAME_MAX + 2 /*"> "*/ + 1 /*"\0"*/ ];
if (!prompt[0]) {
snprintf(prompt, sizeof(prompt), "%s> ", g_get_prgname());
}
return prompt;
}
static void G_GNUC_PRINTF(2, 3) readline_printf_func(void *opaque,
const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vprintf(fmt, ap);
va_end(ap);
}
static void readline_flush_func(void *opaque)
{
fflush(stdout);
}
static void readline_func(void *opaque, const char *str, void *readline_opaque)
{
char **line = readline_opaque;
*line = g_strdup(str);
}
static void completion_match(const char *cmd, void *opaque)
{
readline_add_completion(readline_state, cmd);
}
static void readline_completion_func(void *opaque, const char *str)
{
readline_set_completion_index(readline_state, strlen(str));
qemuio_complete_command(str, completion_match, NULL);
}
static char *fetchline_readline(void)
{
char *line = NULL;
readline_start(readline_state, get_prompt(), 0, readline_func, &line);
while (!line) {
int ch = getchar();
if (ttyEOF != 0x0 && ch == ttyEOF) {
printf("\n");
break;
}
readline_handle_byte(readline_state, ch);
}
return line;
}
#define MAXREADLINESZ 1024
static char *fetchline_fgets(void)
{
char *p, *line = g_malloc(MAXREADLINESZ);
if (!fgets(line, MAXREADLINESZ, stdin)) {
g_free(line);
return NULL;
}
p = line + strlen(line);
if (p != line && p[-1] == '\n') {
p[-1] = '\0';
}
return line;
}
static char *fetchline(void)
{
if (readline_state) {
return fetchline_readline();
} else {
return fetchline_fgets();
}
}
static void prep_fetchline(void *opaque)
{
int *fetchable = opaque;
qemu_set_fd_handler(STDIN_FILENO, NULL, NULL, NULL);
*fetchable= 1;
}
static int do_qemuio_command(const char *cmd)
{
return qemuio_command(qemuio_blk, cmd);
}
static int command_loop(void)
{
int i, fetchable = 0, prompted = 0;
int ret, last_error = 0;
char *input;
for (i = 0; !quit_qemu_io && i < ncmdline; i++) {
ret = do_qemuio_command(cmdline[i]);
if (ret < 0) {
last_error = ret;
}
}
if (cmdline) {
g_free(cmdline);
return last_error;
}
while (!quit_qemu_io) {
if (!prompted) {
printf("%s", get_prompt());
fflush(stdout);
qemu_set_fd_handler(STDIN_FILENO, prep_fetchline, NULL, &fetchable);
prompted = 1;
}
main_loop_wait(false);
if (!fetchable) {
continue;
}
input = fetchline();
if (input == NULL) {
break;
}
ret = do_qemuio_command(input);
g_free(input);
if (ret < 0) {
last_error = ret;
}
prompted = 0;
fetchable = 0;
}
qemu_set_fd_handler(STDIN_FILENO, NULL, NULL, NULL);
return last_error;
}
static void add_user_command(char *user_cmd)
{
cmdline = g_renew(char *, cmdline, ++ncmdline);
cmdline[ncmdline - 1] = user_cmd;
}
static void reenable_tty_echo(void)
{
qemu_set_tty_echo(STDIN_FILENO, true);
}
enum {
OPTION_OBJECT = 256,
OPTION_IMAGE_OPTS = 257,
};
static QemuOptsList file_opts = {
.name = "file",
.implied_opt_name = "file",
.head = QTAILQ_HEAD_INITIALIZER(file_opts.head),
.desc = {
/* no elements => accept any params */
{ /* end of list */ }
},
};
int main(int argc, char **argv)
{
int readonly = 0;
const char *sopt = "hVc:d:f:rsnCmki:t:T:U";
const struct option lopt[] = {
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, 'V' },
{ "cmd", required_argument, NULL, 'c' },
{ "format", required_argument, NULL, 'f' },
{ "read-only", no_argument, NULL, 'r' },
{ "snapshot", no_argument, NULL, 's' },
{ "nocache", no_argument, NULL, 'n' },
{ "copy-on-read", no_argument, NULL, 'C' },
{ "misalign", no_argument, NULL, 'm' },
{ "native-aio", no_argument, NULL, 'k' },
{ "aio", required_argument, NULL, 'i' },
{ "discard", required_argument, NULL, 'd' },
{ "cache", required_argument, NULL, 't' },
{ "trace", required_argument, NULL, 'T' },
{ "object", required_argument, NULL, OPTION_OBJECT },
{ "image-opts", no_argument, NULL, OPTION_IMAGE_OPTS },
{ "force-share", no_argument, 0, 'U'},
{ NULL, 0, NULL, 0 }
};
int c;
int opt_index = 0;
int flags = BDRV_O_UNMAP;
int ret;
bool writethrough = true;
QDict *opts = NULL;
const char *format = NULL;
bool force_share = false;
#ifdef CONFIG_POSIX
signal(SIGPIPE, SIG_IGN);
#endif
socket_init();
error_init(argv[0]);
module_call_init(MODULE_INIT_TRACE);
qemu_init_exec_dir(argv[0]);
qcrypto_init(&error_fatal);
module_call_init(MODULE_INIT_QOM);
qemu_add_opts(&qemu_trace_opts);
bdrv_init();
while ((c = getopt_long(argc, argv, sopt, lopt, &opt_index)) != -1) {
switch (c) {
case 's':
flags |= BDRV_O_SNAPSHOT;
break;
case 'n':
flags |= BDRV_O_NOCACHE;
writethrough = false;
break;
case 'C':
flags |= BDRV_O_COPY_ON_READ;
break;
case 'd':
if (bdrv_parse_discard_flags(optarg, &flags) < 0) {
error_report("Invalid discard option: %s", optarg);
exit(1);
}
break;
case 'f':
format = optarg;
break;
case 'c':
add_user_command(optarg);
break;
case 'r':
readonly = 1;
break;
case 'm':
qemuio_misalign = true;
break;
case 'k':
flags |= BDRV_O_NATIVE_AIO;
break;
case 'i':
if (bdrv_parse_aio(optarg, &flags) < 0) {
error_report("Invalid aio option: %s", optarg);
exit(1);
}
break;
case 't':
if (bdrv_parse_cache_mode(optarg, &flags, &writethrough) < 0) {
error_report("Invalid cache option: %s", optarg);
exit(1);
}
break;
case 'T':
trace_opt_parse(optarg);
break;
case 'V':
printf("%s version " QEMU_FULL_VERSION "\n"
QEMU_COPYRIGHT "\n", g_get_prgname());
exit(0);
case 'h':
usage(g_get_prgname());
exit(0);
case 'U':
force_share = true;
break;
case OPTION_OBJECT:
user_creatable_process_cmdline(optarg);
break;
case OPTION_IMAGE_OPTS:
imageOpts = true;
break;
default:
usage(g_get_prgname());
exit(1);
}
}
if ((argc - optind) > 1) {
usage(g_get_prgname());
exit(1);
}
if (format && imageOpts) {
error_report("--image-opts and -f are mutually exclusive");
exit(1);
}
qemu_init_main_loop(&error_fatal);
if (!trace_init_backends()) {
exit(1);
}
trace_init_file();
qemu_set_log(LOG_TRACE, &error_fatal);
/* initialize commands */
qemuio_add_command(&quit_cmd);
qemuio_add_command(&open_cmd);
qemuio_add_command(&close_cmd);
if (isatty(STDIN_FILENO)) {
ttyEOF = get_eof_char();
readline_state = readline_init(readline_printf_func,
readline_flush_func,
NULL,
readline_completion_func);
qemu_set_tty_echo(STDIN_FILENO, false);
atexit(reenable_tty_echo);
}
/* open the device */
if (!readonly) {
flags |= BDRV_O_RDWR;
}
if ((argc - optind) == 1) {
if (imageOpts) {
QemuOpts *qopts = NULL;
qopts = qemu_opts_parse_noisily(&file_opts, argv[optind], false);
if (!qopts) {
exit(1);
}
opts = qemu_opts_to_qdict(qopts, NULL);
if (openfile(NULL, flags, writethrough, force_share, opts)) {
exit(1);
}
} else {
if (format) {
opts = qdict_new();
qdict_put_str(opts, "driver", format);
}
if (openfile(argv[optind], flags, writethrough,
force_share, opts)) {
exit(1);
}
}
}
ret = command_loop();
/*
* Make sure all outstanding requests complete before the program exits.
*/
bdrv_drain_all();
blk_unref(qemuio_blk);
g_free(readline_state);
if (ret < 0) {
return 1;
} else {
return 0;
}
}