qemu/qemu-io.c
Max Reitz 4c7b7e9b94 qemu-io: Use BlockBackend
qemu-io should behave like a guest, therefore it should use BlockBackend
to access the block layer.

There are a couple of places where that is infeasible: First, the
bdrv_debug_* functions could theoretically be mirrored in the
BlockBackend, but since these are functions internal to the block layer,
they should not be visible externally (qemu-io as a test tool is exempt
from this).

Second, bdrv_get_info() and bdrv_get_specific_info() work on a single
BDS alone, therefore they should stay BDS-specific.

Third, bdrv_is_allocated() mainly works on a single BDS as well. Some
data may be passed through from the BDS's file (if sectors which are
apparently allocated in the file are not really allocated there but just
zero).

[Fixed conflicts around block_acct_start() usage from Fam Zheng's
"qemu-io: Account IO by aio_read and aio_write" commit.  Use
BlockBackend and blk_get_stats() instead of BlockDriverState.
--Stefan]

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1423162705-32065-14-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-02-16 15:07:19 +00:00

481 lines
12 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 <sys/time.h>
#include <sys/types.h>
#include <stdarg.h>
#include <stdio.h>
#include <getopt.h>
#include <libgen.h>
#include "qemu-io.h"
#include "qemu/main-loop.h"
#include "qemu/option.h"
#include "qemu/config-file.h"
#include "qemu/readline.h"
#include "sysemu/block-backend.h"
#include "block/block_int.h"
#include "trace/control.h"
#define CMD_NOFILE_OK 0x01
static char *progname;
static BlockBackend *qemuio_blk;
/* qemu-io commands passed using -c */
static int ncmdline;
static char **cmdline;
static ReadLineState *readline_state;
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, QDict *opts)
{
Error *local_err = NULL;
if (qemuio_blk) {
fprintf(stderr, "file open already, try 'help close'\n");
QDECREF(opts);
return 1;
}
qemuio_blk = blk_new_open("hda", name, NULL, opts, flags, &local_err);
if (!qemuio_blk) {
fprintf(stderr, "%s: can't open%s%s: %s\n", progname,
name ? " device " : "", name ?: "",
error_get_pretty(local_err));
error_free(local_err);
return 1;
}
return 0;
}
static void open_help(void)
{
printf(
"\n"
" opens a new file in the requested mode\n"
"\n"
" Example:\n"
" 'open -Cn /tmp/data' - creates/opens data file read-write and 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"
" -n, -- disable host cache\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 = "[-Crsn] [-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 = 0;
int readonly = 0;
int c;
QemuOpts *qopts;
QDict *opts;
while ((c = getopt(argc, argv, "snrgo:")) != EOF) {
switch (c) {
case 's':
flags |= BDRV_O_SNAPSHOT;
break;
case 'n':
flags |= BDRV_O_NOCACHE | BDRV_O_CACHE_WB;
break;
case 'r':
readonly = 1;
break;
case 'o':
if (!qemu_opts_parse(&empty_opts, optarg, 0)) {
printf("could not parse option list -- %s\n", optarg);
qemu_opts_reset(&empty_opts);
return 0;
}
break;
default:
qemu_opts_reset(&empty_opts);
return qemuio_command_usage(&open_cmd);
}
}
if (!readonly) {
flags |= BDRV_O_RDWR;
}
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) {
return openfile(argv[optind], flags, opts);
} else if (optind == argc) {
return openfile(NULL, flags, opts);
} else {
QDECREF(opts);
return qemuio_command_usage(&open_cmd);
}
}
static int quit_f(BlockBackend *blk, int argc, char **argv)
{
return 1;
}
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 [-h] [-V] [-rsnm] [-f FMT] [-c STRING] ... [file]\n"
"QEMU Disk exerciser\n"
"\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\n"
" -m, --misalign misalign allocations for O_DIRECT\n"
" -k, --native-aio use kernel AIO implementation (on Linux only)\n"
" -t, --cache=MODE use the given cache mode for the image\n"
" -T, --trace FILE enable trace events listed in the given file\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",
name, name);
}
static char *get_prompt(void)
{
static char prompt[FILENAME_MAX + 2 /*"> "*/ + 1 /*"\0"*/ ];
if (!prompt[0]) {
snprintf(prompt, sizeof(prompt), "%s> ", progname);
}
return prompt;
}
static void GCC_FMT_ATTR(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 (ch == EOF) {
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 void command_loop(void)
{
int i, done = 0, fetchable = 0, prompted = 0;
char *input;
for (i = 0; !done && i < ncmdline; i++) {
done = qemuio_command(qemuio_blk, cmdline[i]);
}
if (cmdline) {
g_free(cmdline);
return;
}
while (!done) {
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;
}
done = qemuio_command(qemuio_blk, input);
g_free(input);
prompted = 0;
fetchable = 0;
}
qemu_set_fd_handler(STDIN_FILENO, NULL, NULL, NULL);
}
static void add_user_command(char *optarg)
{
cmdline = g_renew(char *, cmdline, ++ncmdline);
cmdline[ncmdline-1] = optarg;
}
static void reenable_tty_echo(void)
{
qemu_set_tty_echo(STDIN_FILENO, true);
}
int main(int argc, char **argv)
{
int readonly = 0;
const char *sopt = "hVc:d:f:rsnmgkt:T:";
const struct option lopt[] = {
{ "help", 0, NULL, 'h' },
{ "version", 0, NULL, 'V' },
{ "offset", 1, NULL, 'o' },
{ "cmd", 1, NULL, 'c' },
{ "format", 1, NULL, 'f' },
{ "read-only", 0, NULL, 'r' },
{ "snapshot", 0, NULL, 's' },
{ "nocache", 0, NULL, 'n' },
{ "misalign", 0, NULL, 'm' },
{ "native-aio", 0, NULL, 'k' },
{ "discard", 1, NULL, 'd' },
{ "cache", 1, NULL, 't' },
{ "trace", 1, NULL, 'T' },
{ NULL, 0, NULL, 0 }
};
int c;
int opt_index = 0;
int flags = BDRV_O_UNMAP;
Error *local_error = NULL;
QDict *opts = NULL;
#ifdef CONFIG_POSIX
signal(SIGPIPE, SIG_IGN);
#endif
progname = basename(argv[0]);
qemu_init_exec_dir(argv[0]);
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 | BDRV_O_CACHE_WB;
break;
case 'd':
if (bdrv_parse_discard_flags(optarg, &flags) < 0) {
error_report("Invalid discard option: %s", optarg);
exit(1);
}
break;
case 'f':
if (!opts) {
opts = qdict_new();
}
qdict_put(opts, "driver", qstring_from_str(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 't':
if (bdrv_parse_cache_flags(optarg, &flags) < 0) {
error_report("Invalid cache option: %s", optarg);
exit(1);
}
break;
case 'T':
if (!trace_init_backends(optarg, NULL)) {
exit(1); /* error message will have been printed */
}
break;
case 'V':
printf("%s version %s\n", progname, QEMU_VERSION);
exit(0);
case 'h':
usage(progname);
exit(0);
default:
usage(progname);
exit(1);
}
}
if ((argc - optind) > 1) {
usage(progname);
exit(1);
}
if (qemu_init_main_loop(&local_error)) {
error_report("%s", error_get_pretty(local_error));
error_free(local_error);
exit(1);
}
/* initialize commands */
qemuio_add_command(&quit_cmd);
qemuio_add_command(&open_cmd);
qemuio_add_command(&close_cmd);
if (isatty(STDIN_FILENO)) {
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) {
openfile(argv[optind], flags, opts);
}
command_loop();
/*
* Make sure all outstanding requests complete before the program exits.
*/
bdrv_drain_all();
blk_unref(qemuio_blk);
g_free(readline_state);
return 0;
}