qemu-io: Add discard command

[qemu/mdroth.git] / qemu-io.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-common.h"
#include "block_int.h"
#include "cmd.h"

#define VERSION "0.0.1"

#define CMD_NOFILE_OK   0x01

char *progname;
static BlockDriverState *bs;

static int misalign;

/*
 * Parse the pattern argument to various sub-commands.
 *
 * Because the pattern is used as an argument to memset it must evaluate
 * to an unsigned integer that fits into a single byte.
 */
static int parse_pattern(const char *arg)
{
        char *endptr = NULL;
        long pattern;

        pattern = strtol(arg, &endptr, 0);
        if (pattern < 0 || pattern > UCHAR_MAX || *endptr != '\0') {
                printf("%s is not a valid pattern byte\n", arg);
                return -1;
        }

        return pattern;
}

/*
 * Memory allocation helpers.
 *
 * Make sure memory is aligned by default, or purposefully misaligned if
 * that is specified on the command line.
 */

#define MISALIGN_OFFSET         16
static void *qemu_io_alloc(size_t len, int pattern)
{
        void *buf;

        if (misalign)
                len += MISALIGN_OFFSET;
        buf = qemu_blockalign(bs, len);
        memset(buf, pattern, len);
        if (misalign)
                buf += MISALIGN_OFFSET;
        return buf;
}

static void qemu_io_free(void *p)
{
        if (misalign)
                p -= MISALIGN_OFFSET;
        qemu_vfree(p);
}

static void
dump_buffer(const void *buffer, int64_t offset, int len)
{
        int i, j;
        const uint8_t *p;

        for (i = 0, p = buffer; i < len; i += 16) {
                const uint8_t *s = p;

                printf("%08" PRIx64 ":  ", offset + i);
                for (j = 0; j < 16 && i + j < len; j++, p++)
                        printf("%02x ", *p);
                printf(" ");
                for (j = 0; j < 16 && i + j < len; j++, s++) {
                        if (isalnum(*s))
                                printf("%c", *s);
                        else
                                printf(".");
                }
                printf("\n");
        }
}

static void
print_report(const char *op, struct timeval *t, int64_t offset,
                int count, int total, int cnt, int Cflag)
{
        char s1[64], s2[64], ts[64];

        timestr(t, ts, sizeof(ts), Cflag ? VERBOSE_FIXED_TIME : 0);
        if (!Cflag) {
                cvtstr((double)total, s1, sizeof(s1));
                cvtstr(tdiv((double)total, *t), s2, sizeof(s2));
                printf("%s %d/%d bytes at offset %" PRId64 "\n",
                       op, total, count, offset);
                printf("%s, %d ops; %s (%s/sec and %.4f ops/sec)\n",
                        s1, cnt, ts, s2, tdiv((double)cnt, *t));
        } else {/* bytes,ops,time,bytes/sec,ops/sec */
                printf("%d,%d,%s,%.3f,%.3f\n",
                        total, cnt, ts,
                        tdiv((double)total, *t),
                        tdiv((double)cnt, *t));
        }
}

/*
 * Parse multiple length statements for vectored I/O, and construct an I/O
 * vector matching it.
 */
static void *
create_iovec(QEMUIOVector *qiov, char **argv, int nr_iov, int pattern)
{
        size_t *sizes = calloc(nr_iov, sizeof(size_t));
        size_t count = 0;
        void *buf = NULL;
        void *p;
        int i;

        for (i = 0; i < nr_iov; i++) {
                char *arg = argv[i];
                int64_t len;

                len = cvtnum(arg);
                if (len < 0) {
                        printf("non-numeric length argument -- %s\n", arg);
                        goto fail;
                }

                /* should be SIZE_T_MAX, but that doesn't exist */
                if (len > INT_MAX) {
                        printf("too large length argument -- %s\n", arg);
                        goto fail;
                }

                if (len & 0x1ff) {
                        printf("length argument %" PRId64
                               " is not sector aligned\n", len);
                        goto fail;
                }

                sizes[i] = len;
                count += len;
        }

        qemu_iovec_init(qiov, nr_iov);

        buf = p = qemu_io_alloc(count, pattern);

        for (i = 0; i < nr_iov; i++) {
                qemu_iovec_add(qiov, p, sizes[i]);
                p += sizes[i];
        }

fail:
        free(sizes);
        return buf;
}

static int do_read(char *buf, int64_t offset, int count, int *total)
{
        int ret;

        ret = bdrv_read(bs, offset >> 9, (uint8_t *)buf, count >> 9);
        if (ret < 0)
                return ret;
        *total = count;
        return 1;
}

static int do_write(char *buf, int64_t offset, int count, int *total)
{
        int ret;

        ret = bdrv_write(bs, offset >> 9, (uint8_t *)buf, count >> 9);
        if (ret < 0)
                return ret;
        *total = count;
        return 1;
}

static int do_pread(char *buf, int64_t offset, int count, int *total)
{
        *total = bdrv_pread(bs, offset, (uint8_t *)buf, count);
        if (*total < 0)
                return *total;
        return 1;
}

static int do_pwrite(char *buf, int64_t offset, int count, int *total)
{
        *total = bdrv_pwrite(bs, offset, (uint8_t *)buf, count);
        if (*total < 0)
                return *total;
        return 1;
}

static int do_load_vmstate(char *buf, int64_t offset, int count, int *total)
{
        *total = bdrv_load_vmstate(bs, (uint8_t *)buf, offset, count);
        if (*total < 0)
                return *total;
        return 1;
}

static int do_save_vmstate(char *buf, int64_t offset, int count, int *total)
{
        *total = bdrv_save_vmstate(bs, (uint8_t *)buf, offset, count);
        if (*total < 0)
                return *total;
        return 1;
}

#define NOT_DONE 0x7fffffff
static void aio_rw_done(void *opaque, int ret)
{
        *(int *)opaque = ret;
}

static int do_aio_readv(QEMUIOVector *qiov, int64_t offset, int *total)
{
        BlockDriverAIOCB *acb;
        int async_ret = NOT_DONE;

        acb = bdrv_aio_readv(bs, offset >> 9, qiov, qiov->size >> 9,
                             aio_rw_done, &async_ret);
        if (!acb)
                return -EIO;

        while (async_ret == NOT_DONE)
                qemu_aio_wait();

        *total = qiov->size;
        return async_ret < 0 ? async_ret : 1;
}

static int do_aio_writev(QEMUIOVector *qiov, int64_t offset, int *total)
{
        BlockDriverAIOCB *acb;
        int async_ret = NOT_DONE;

        acb = bdrv_aio_writev(bs, offset >> 9, qiov, qiov->size >> 9,
                              aio_rw_done, &async_ret);
        if (!acb)
                return -EIO;

        while (async_ret == NOT_DONE)
                qemu_aio_wait();

        *total = qiov->size;
        return async_ret < 0 ? async_ret : 1;
}

struct multiwrite_async_ret {
        int num_done;
        int error;
};

static void multiwrite_cb(void *opaque, int ret)
{
        struct multiwrite_async_ret *async_ret = opaque;

        async_ret->num_done++;
        if (ret < 0) {
                async_ret->error = ret;
        }
}

static int do_aio_multiwrite(BlockRequest* reqs, int num_reqs, int *total)
{
        int i, ret;
        struct multiwrite_async_ret async_ret = {
                .num_done = 0,
                .error = 0,
        };

        *total = 0;
        for (i = 0; i < num_reqs; i++) {
                reqs[i].cb = multiwrite_cb;
                reqs[i].opaque = &async_ret;
                *total += reqs[i].qiov->size;
        }

        ret = bdrv_aio_multiwrite(bs, reqs, num_reqs);
        if (ret < 0) {
                return ret;
        }

        while (async_ret.num_done < num_reqs) {
                qemu_aio_wait();
        }

        return async_ret.error < 0 ? async_ret.error : 1;
}

static void
read_help(void)
{
        printf(
"\n"
" reads a range of bytes from the given offset\n"
"\n"
" Example:\n"
" 'read -v 512 1k' - dumps 1 kilobyte read from 512 bytes into the file\n"
"\n"
" Reads a segment of the currently open file, optionally dumping it to the\n"
" standard output stream (with -v option) for subsequent inspection.\n"
" -b, -- read from the VM state rather than the virtual disk\n"
" -C, -- report statistics in a machine parsable format\n"
" -l, -- length for pattern verification (only with -P)\n"
" -p, -- use bdrv_pread to read the file\n"
" -P, -- use a pattern to verify read data\n"
" -q, -- quite mode, do not show I/O statistics\n"
" -s, -- start offset for pattern verification (only with -P)\n"
" -v, -- dump buffer to standard output\n"
"\n");
}

static int read_f(int argc, char **argv);

static const cmdinfo_t read_cmd = {
        .name           = "read",
        .altname        = "r",
        .cfunc          = read_f,
        .argmin         = 2,
        .argmax         = -1,
        .args           = "[-abCpqv] [-P pattern [-s off] [-l len]] off len",
        .oneline        = "reads a number of bytes at a specified offset",
        .help           = read_help,
};

static int
read_f(int argc, char **argv)
{
        struct timeval t1, t2;
        int Cflag = 0, pflag = 0, qflag = 0, vflag = 0;
        int Pflag = 0, sflag = 0, lflag = 0, bflag = 0;
        int c, cnt;
        char *buf;
        int64_t offset;
        int count;
        /* Some compilers get confused and warn if this is not initialized.  */
        int total = 0;
        int pattern = 0, pattern_offset = 0, pattern_count = 0;

        while ((c = getopt(argc, argv, "bCl:pP:qs:v")) != EOF) {
                switch (c) {
                case 'b':
                        bflag = 1;
                        break;
                case 'C':
                        Cflag = 1;
                        break;
                case 'l':
                        lflag = 1;
                        pattern_count = cvtnum(optarg);
                        if (pattern_count < 0) {
                                printf("non-numeric length argument -- %s\n", optarg);
                                return 0;
                        }
                        break;
                case 'p':
                        pflag = 1;
                        break;
                case 'P':
                        Pflag = 1;
                        pattern = parse_pattern(optarg);
                        if (pattern < 0)
                                return 0;
                        break;
                case 'q':
                        qflag = 1;
                        break;
                case 's':
                        sflag = 1;
                        pattern_offset = cvtnum(optarg);
                        if (pattern_offset < 0) {
                                printf("non-numeric length argument -- %s\n", optarg);
                                return 0;
                        }
                        break;
                case 'v':
                        vflag = 1;
                        break;
                default:
                        return command_usage(&read_cmd);
                }
        }

        if (optind != argc - 2)
                return command_usage(&read_cmd);

        if (bflag && pflag) {
                printf("-b and -p cannot be specified at the same time\n");
                return 0;
        }

        offset = cvtnum(argv[optind]);
        if (offset < 0) {
                printf("non-numeric length argument -- %s\n", argv[optind]);
                return 0;
        }

        optind++;
        count = cvtnum(argv[optind]);
        if (count < 0) {
                printf("non-numeric length argument -- %s\n", argv[optind]);
                return 0;
        }

    if (!Pflag && (lflag || sflag)) {
        return command_usage(&read_cmd);
    }

    if (!lflag) {
        pattern_count = count - pattern_offset;
    }

    if ((pattern_count < 0) || (pattern_count + pattern_offset > count))  {
        printf("pattern verfication range exceeds end of read data\n");
        return 0;
    }

        if (!pflag)
                if (offset & 0x1ff) {
                        printf("offset %" PRId64 " is not sector aligned\n",
                               offset);
                        return 0;

                if (count & 0x1ff) {
                        printf("count %d is not sector aligned\n",
                                count);
                        return 0;
                }
        }

        buf = qemu_io_alloc(count, 0xab);

        gettimeofday(&t1, NULL);
        if (pflag)
                cnt = do_pread(buf, offset, count, &total);
        else if (bflag)
                cnt = do_load_vmstate(buf, offset, count, &total);
        else
                cnt = do_read(buf, offset, count, &total);
        gettimeofday(&t2, NULL);

        if (cnt < 0) {
                printf("read failed: %s\n", strerror(-cnt));
                goto out;
        }

        if (Pflag) {
                void* cmp_buf = malloc(pattern_count);
                memset(cmp_buf, pattern, pattern_count);
                if (memcmp(buf + pattern_offset, cmp_buf, pattern_count)) {
                        printf("Pattern verification failed at offset %"
                               PRId64 ", %d bytes\n",
                               offset + pattern_offset, pattern_count);
                }
                free(cmp_buf);
        }

        if (qflag)
                goto out;

        if (vflag)
                dump_buffer(buf, offset, count);

        /* Finally, report back -- -C gives a parsable format */
        t2 = tsub(t2, t1);
        print_report("read", &t2, offset, count, total, cnt, Cflag);

out:
        qemu_io_free(buf);

        return 0;
}

static void
readv_help(void)
{
        printf(
"\n"
" reads a range of bytes from the given offset into multiple buffers\n"
"\n"
" Example:\n"
" 'readv -v 512 1k 1k ' - dumps 2 kilobytes read from 512 bytes into the file\n"
"\n"
" Reads a segment of the currently open file, optionally dumping it to the\n"
" standard output stream (with -v option) for subsequent inspection.\n"
" Uses multiple iovec buffers if more than one byte range is specified.\n"
" -C, -- report statistics in a machine parsable format\n"
" -P, -- use a pattern to verify read data\n"
" -v, -- dump buffer to standard output\n"
" -q, -- quite mode, do not show I/O statistics\n"
"\n");
}

static int readv_f(int argc, char **argv);

static const cmdinfo_t readv_cmd = {
        .name           = "readv",
        .cfunc          = readv_f,
        .argmin         = 2,
        .argmax         = -1,
        .args           = "[-Cqv] [-P pattern ] off len [len..]",
        .oneline        = "reads a number of bytes at a specified offset",
        .help           = readv_help,
};

static int
readv_f(int argc, char **argv)
{
        struct timeval t1, t2;
        int Cflag = 0, qflag = 0, vflag = 0;
        int c, cnt;
        char *buf;
        int64_t offset;
        /* Some compilers get confused and warn if this is not initialized.  */
        int total = 0;
        int nr_iov;
        QEMUIOVector qiov;
        int pattern = 0;
        int Pflag = 0;

        while ((c = getopt(argc, argv, "CP:qv")) != EOF) {
                switch (c) {
                case 'C':
                        Cflag = 1;
                        break;
                case 'P':
                        Pflag = 1;
                        pattern = parse_pattern(optarg);
                        if (pattern < 0)
                                return 0;
                        break;
                case 'q':
                        qflag = 1;
                        break;
                case 'v':
                        vflag = 1;
                        break;
                default:
                        return command_usage(&readv_cmd);
                }
        }

        if (optind > argc - 2)
                return command_usage(&readv_cmd);


        offset = cvtnum(argv[optind]);
        if (offset < 0) {
                printf("non-numeric length argument -- %s\n", argv[optind]);
                return 0;
        }
        optind++;

        if (offset & 0x1ff) {
                printf("offset %" PRId64 " is not sector aligned\n",
                       offset);
                return 0;
        }

        nr_iov = argc - optind;
        buf = create_iovec(&qiov, &argv[optind], nr_iov, 0xab);

        gettimeofday(&t1, NULL);
        cnt = do_aio_readv(&qiov, offset, &total);
        gettimeofday(&t2, NULL);

        if (cnt < 0) {
                printf("readv failed: %s\n", strerror(-cnt));
                goto out;
        }

        if (Pflag) {
                void* cmp_buf = malloc(qiov.size);
                memset(cmp_buf, pattern, qiov.size);
                if (memcmp(buf, cmp_buf, qiov.size)) {
                        printf("Pattern verification failed at offset %"
                               PRId64 ", %zd bytes\n",
                               offset, qiov.size);
                }
                free(cmp_buf);
        }

        if (qflag)
                goto out;

        if (vflag)
                dump_buffer(buf, offset, qiov.size);

        /* Finally, report back -- -C gives a parsable format */
        t2 = tsub(t2, t1);
        print_report("read", &t2, offset, qiov.size, total, cnt, Cflag);

out:
        qemu_io_free(buf);
        return 0;
}

static void
write_help(void)
{
        printf(
"\n"
" writes a range of bytes from the given offset\n"
"\n"
" Example:\n"
" 'write 512 1k' - writes 1 kilobyte at 512 bytes into the open file\n"
"\n"
" Writes into a segment of the currently open file, using a buffer\n"
" filled with a set pattern (0xcdcdcdcd).\n"
" -b, -- write to the VM state rather than the virtual disk\n"
" -p, -- use bdrv_pwrite to write the file\n"
" -P, -- use different pattern to fill file\n"
" -C, -- report statistics in a machine parsable format\n"
" -q, -- quite mode, do not show I/O statistics\n"
"\n");
}

static int write_f(int argc, char **argv);

static const cmdinfo_t write_cmd = {
        .name           = "write",
        .altname        = "w",
        .cfunc          = write_f,
        .argmin         = 2,
        .argmax         = -1,
        .args           = "[-abCpq] [-P pattern ] off len",
        .oneline        = "writes a number of bytes at a specified offset",
        .help           = write_help,
};

static int
write_f(int argc, char **argv)
{
        struct timeval t1, t2;
        int Cflag = 0, pflag = 0, qflag = 0, bflag = 0;
        int c, cnt;
        char *buf;
        int64_t offset;
        int count;
        /* Some compilers get confused and warn if this is not initialized.  */
        int total = 0;
        int pattern = 0xcd;

        while ((c = getopt(argc, argv, "bCpP:q")) != EOF) {
                switch (c) {
                case 'b':
                        bflag = 1;
                        break;
                case 'C':
                        Cflag = 1;
                        break;
                case 'p':
                        pflag = 1;
                        break;
                case 'P':
                        pattern = parse_pattern(optarg);
                        if (pattern < 0)
                                return 0;
                        break;
                case 'q':
                        qflag = 1;
                        break;
                default:
                        return command_usage(&write_cmd);
                }
        }

        if (optind != argc - 2)
                return command_usage(&write_cmd);

        if (bflag && pflag) {
                printf("-b and -p cannot be specified at the same time\n");
                return 0;
        }

        offset = cvtnum(argv[optind]);
        if (offset < 0) {
                printf("non-numeric length argument -- %s\n", argv[optind]);
                return 0;
        }

        optind++;
        count = cvtnum(argv[optind]);
        if (count < 0) {
                printf("non-numeric length argument -- %s\n", argv[optind]);
                return 0;
        }

        if (!pflag) {
                if (offset & 0x1ff) {
                        printf("offset %" PRId64 " is not sector aligned\n",
                               offset);
                        return 0;
                }

                if (count & 0x1ff) {
                        printf("count %d is not sector aligned\n",
                                count);
                        return 0;
                }
        }

        buf = qemu_io_alloc(count, pattern);

        gettimeofday(&t1, NULL);
        if (pflag)
                cnt = do_pwrite(buf, offset, count, &total);
        else if (bflag)
                cnt = do_save_vmstate(buf, offset, count, &total);
        else
                cnt = do_write(buf, offset, count, &total);
        gettimeofday(&t2, NULL);

        if (cnt < 0) {
                printf("write failed: %s\n", strerror(-cnt));
                goto out;
        }

        if (qflag)
                goto out;

        /* Finally, report back -- -C gives a parsable format */
        t2 = tsub(t2, t1);
        print_report("wrote", &t2, offset, count, total, cnt, Cflag);

out:
        qemu_io_free(buf);

        return 0;
}

static void
writev_help(void)
{
        printf(
"\n"
" writes a range of bytes from the given offset source from multiple buffers\n"
"\n"
" Example:\n"
" 'write 512 1k 1k' - writes 2 kilobytes at 512 bytes into the open file\n"
"\n"
" Writes into a segment of the currently open file, using a buffer\n"
" filled with a set pattern (0xcdcdcdcd).\n"
" -P, -- use different pattern to fill file\n"
" -C, -- report statistics in a machine parsable format\n"
" -q, -- quite mode, do not show I/O statistics\n"
"\n");
}

static int writev_f(int argc, char **argv);

static const cmdinfo_t writev_cmd = {
        .name           = "writev",
        .cfunc          = writev_f,
        .argmin         = 2,
        .argmax         = -1,
        .args           = "[-Cq] [-P pattern ] off len [len..]",
        .oneline        = "writes a number of bytes at a specified offset",
        .help           = writev_help,
};

static int
writev_f(int argc, char **argv)
{
        struct timeval t1, t2;
        int Cflag = 0, qflag = 0;
        int c, cnt;
        char *buf;
        int64_t offset;
        /* Some compilers get confused and warn if this is not initialized.  */
        int total = 0;
        int nr_iov;
        int pattern = 0xcd;
        QEMUIOVector qiov;

        while ((c = getopt(argc, argv, "CqP:")) != EOF) {
                switch (c) {
                case 'C':
                        Cflag = 1;
                        break;
                case 'q':
                        qflag = 1;
                        break;
                case 'P':
                        pattern = parse_pattern(optarg);
                        if (pattern < 0)
                                return 0;
                        break;
                default:
                        return command_usage(&writev_cmd);
                }
        }

        if (optind > argc - 2)
                return command_usage(&writev_cmd);

        offset = cvtnum(argv[optind]);
        if (offset < 0) {
                printf("non-numeric length argument -- %s\n", argv[optind]);
                return 0;
        }
        optind++;

        if (offset & 0x1ff) {
                printf("offset %" PRId64 " is not sector aligned\n",
                       offset);
                return 0;
        }

        nr_iov = argc - optind;
        buf = create_iovec(&qiov, &argv[optind], nr_iov, pattern);

        gettimeofday(&t1, NULL);
        cnt = do_aio_writev(&qiov, offset, &total);
        gettimeofday(&t2, NULL);

        if (cnt < 0) {
                printf("writev failed: %s\n", strerror(-cnt));
                goto out;
        }

        if (qflag)
                goto out;

        /* Finally, report back -- -C gives a parsable format */
        t2 = tsub(t2, t1);
        print_report("wrote", &t2, offset, qiov.size, total, cnt, Cflag);
out:
        qemu_io_free(buf);
        return 0;
}

static void
multiwrite_help(void)
{
        printf(
"\n"
" writes a range of bytes from the given offset source from multiple buffers,\n"
" in a batch of requests that may be merged by qemu\n"
"\n"
" Example:\n"
" 'multiwrite 512 1k 1k ; 4k 1k' \n"
"  writes 2 kB at 512 bytes and 1 kB at 4 kB into the open file\n"
"\n"
" Writes into a segment of the currently open file, using a buffer\n"
" filled with a set pattern (0xcdcdcdcd). The pattern byte is increased\n"
" by one for each request contained in the multiwrite command.\n"
" -P, -- use different pattern to fill file\n"
" -C, -- report statistics in a machine parsable format\n"
" -q, -- quiet mode, do not show I/O statistics\n"
"\n");
}

static int multiwrite_f(int argc, char **argv);

static const cmdinfo_t multiwrite_cmd = {
        .name           = "multiwrite",
        .cfunc          = multiwrite_f,
        .argmin         = 2,
        .argmax         = -1,
        .args           = "[-Cq] [-P pattern ] off len [len..] [; off len [len..]..]",
        .oneline        = "issues multiple write requests at once",
        .help           = multiwrite_help,
};

static int
multiwrite_f(int argc, char **argv)
{
        struct timeval t1, t2;
        int Cflag = 0, qflag = 0;
        int c, cnt;
        char **buf;
        int64_t offset, first_offset = 0;
        /* Some compilers get confused and warn if this is not initialized.  */
        int total = 0;
        int nr_iov;
        int nr_reqs;
        int pattern = 0xcd;
        QEMUIOVector *qiovs;
        int i;
        BlockRequest *reqs;

        while ((c = getopt(argc, argv, "CqP:")) != EOF) {
                switch (c) {
                case 'C':
                        Cflag = 1;
                        break;
                case 'q':
                        qflag = 1;
                        break;
                case 'P':
                        pattern = parse_pattern(optarg);
                        if (pattern < 0)
                                return 0;
                        break;
                default:
                        return command_usage(&writev_cmd);
                }
        }

        if (optind > argc - 2)
                return command_usage(&writev_cmd);

        nr_reqs = 1;
        for (i = optind; i < argc; i++) {
                if (!strcmp(argv[i], ";")) {
                        nr_reqs++;
                }
        }

        reqs = qemu_malloc(nr_reqs * sizeof(*reqs));
        buf = qemu_malloc(nr_reqs * sizeof(*buf));
        qiovs = qemu_malloc(nr_reqs * sizeof(*qiovs));

        for (i = 0; i < nr_reqs; i++) {
                int j;

                /* Read the offset of the request */
                offset = cvtnum(argv[optind]);
                if (offset < 0) {
                        printf("non-numeric offset argument -- %s\n", argv[optind]);
                        return 0;
                }
                optind++;

                if (offset & 0x1ff) {
                        printf("offset %lld is not sector aligned\n",
                                (long long)offset);
                        return 0;
                }

        if (i == 0) {
            first_offset = offset;
        }

                /* Read lengths for qiov entries */
                for (j = optind; j < argc; j++) {
                        if (!strcmp(argv[j], ";")) {
                                break;
                        }
                }

                nr_iov = j - optind;

                /* Build request */
                reqs[i].qiov = &qiovs[i];
                buf[i] = create_iovec(reqs[i].qiov, &argv[optind], nr_iov, pattern);
                reqs[i].sector = offset >> 9;
                reqs[i].nb_sectors = reqs[i].qiov->size >> 9;

                optind = j + 1;

                offset += reqs[i].qiov->size;
                pattern++;
        }

        gettimeofday(&t1, NULL);
        cnt = do_aio_multiwrite(reqs, nr_reqs, &total);
        gettimeofday(&t2, NULL);

        if (cnt < 0) {
                printf("aio_multiwrite failed: %s\n", strerror(-cnt));
                goto out;
        }

        if (qflag)
                goto out;

        /* Finally, report back -- -C gives a parsable format */
        t2 = tsub(t2, t1);
        print_report("wrote", &t2, first_offset, total, total, cnt, Cflag);
out:
        for (i = 0; i < nr_reqs; i++) {
                qemu_io_free(buf[i]);
                qemu_iovec_destroy(&qiovs[i]);
        }
        qemu_free(buf);
        qemu_free(reqs);
        qemu_free(qiovs);
        return 0;
}

struct aio_ctx {
        QEMUIOVector qiov;
        int64_t offset;
        char *buf;
        int qflag;
        int vflag;
        int Cflag;
        int Pflag;
        int pattern;
        struct timeval t1;
};

static void
aio_write_done(void *opaque, int ret)
{
        struct aio_ctx *ctx = opaque;
        struct timeval t2;

        gettimeofday(&t2, NULL);


        if (ret < 0) {
                printf("aio_write failed: %s\n", strerror(-ret));
                goto out;
        }

        if (ctx->qflag) {
                goto out;
        }

        /* Finally, report back -- -C gives a parsable format */
        t2 = tsub(t2, ctx->t1);
        print_report("wrote", &t2, ctx->offset, ctx->qiov.size,
                     ctx->qiov.size, 1, ctx->Cflag);
out:
        qemu_io_free(ctx->buf);
        free(ctx);
}

static void
aio_read_done(void *opaque, int ret)
{
        struct aio_ctx *ctx = opaque;
        struct timeval t2;

        gettimeofday(&t2, NULL);

        if (ret < 0) {
                printf("readv failed: %s\n", strerror(-ret));
                goto out;
        }

        if (ctx->Pflag) {
                void *cmp_buf = malloc(ctx->qiov.size);

                memset(cmp_buf, ctx->pattern, ctx->qiov.size);
                if (memcmp(ctx->buf, cmp_buf, ctx->qiov.size)) {
                        printf("Pattern verification failed at offset %"
                               PRId64 ", %zd bytes\n",
                               ctx->offset, ctx->qiov.size);
                }
                free(cmp_buf);
        }

        if (ctx->qflag) {
                goto out;
        }

        if (ctx->vflag) {
                dump_buffer(ctx->buf, ctx->offset, ctx->qiov.size);
        }

        /* Finally, report back -- -C gives a parsable format */
        t2 = tsub(t2, ctx->t1);
        print_report("read", &t2, ctx->offset, ctx->qiov.size,
                     ctx->qiov.size, 1, ctx->Cflag);
out:
        qemu_io_free(ctx->buf);
        free(ctx);
}

static void
aio_read_help(void)
{
        printf(
"\n"
" asynchronously reads a range of bytes from the given offset\n"
"\n"
" Example:\n"
" 'aio_read -v 512 1k 1k ' - dumps 2 kilobytes read from 512 bytes into the file\n"
"\n"
" Reads a segment of the currently open file, optionally dumping it to the\n"
" standard output stream (with -v option) for subsequent inspection.\n"
" The read is performed asynchronously and the aio_flush command must be\n"
" used to ensure all outstanding aio requests have been completed\n"
" -C, -- report statistics in a machine parsable format\n"
" -P, -- use a pattern to verify read data\n"
" -v, -- dump buffer to standard output\n"
" -q, -- quite mode, do not show I/O statistics\n"
"\n");
}

static int aio_read_f(int argc, char **argv);

static const cmdinfo_t aio_read_cmd = {
        .name           = "aio_read",
        .cfunc          = aio_read_f,
        .argmin         = 2,
        .argmax         = -1,
        .args           = "[-Cqv] [-P pattern ] off len [len..]",
        .oneline        = "asynchronously reads a number of bytes",
        .help           = aio_read_help,
};

static int
aio_read_f(int argc, char **argv)
{
        int nr_iov, c;
        struct aio_ctx *ctx = calloc(1, sizeof(struct aio_ctx));
        BlockDriverAIOCB *acb;

        while ((c = getopt(argc, argv, "CP:qv")) != EOF) {
                switch (c) {
                case 'C':
                        ctx->Cflag = 1;
                        break;
                case 'P':
                        ctx->Pflag = 1;
                        ctx->pattern = parse_pattern(optarg);
                        if (ctx->pattern < 0)
                                return 0;
                        break;
                case 'q':
                        ctx->qflag = 1;
                        break;
                case 'v':
                        ctx->vflag = 1;
                        break;
                default:
                        free(ctx);
                        return command_usage(&aio_read_cmd);
                }
        }

        if (optind > argc - 2) {
                free(ctx);
                return command_usage(&aio_read_cmd);
        }

        ctx->offset = cvtnum(argv[optind]);
        if (ctx->offset < 0) {
                printf("non-numeric length argument -- %s\n", argv[optind]);
                free(ctx);
                return 0;
        }
        optind++;

        if (ctx->offset & 0x1ff) {
                printf("offset %" PRId64 " is not sector aligned\n",
                       ctx->offset);
                free(ctx);
                return 0;
        }

        nr_iov = argc - optind;
        ctx->buf = create_iovec(&ctx->qiov, &argv[optind], nr_iov, 0xab);

        gettimeofday(&ctx->t1, NULL);
        acb = bdrv_aio_readv(bs, ctx->offset >> 9, &ctx->qiov,
                              ctx->qiov.size >> 9, aio_read_done, ctx);
        if (!acb) {
                free(ctx->buf);
                free(ctx);
                return -EIO;
        }

        return 0;
}

static void
aio_write_help(void)
{
        printf(
"\n"
" asynchronously writes a range of bytes from the given offset source \n"
" from multiple buffers\n"
"\n"
" Example:\n"
" 'aio_write 512 1k 1k' - writes 2 kilobytes at 512 bytes into the open file\n"
"\n"
" Writes into a segment of the currently open file, using a buffer\n"
" filled with a set pattern (0xcdcdcdcd).\n"
" The write is performed asynchronously and the aio_flush command must be\n"
" used to ensure all outstanding aio requests have been completed\n"
" -P, -- use different pattern to fill file\n"
" -C, -- report statistics in a machine parsable format\n"
" -q, -- quite mode, do not show I/O statistics\n"
"\n");
}

static int aio_write_f(int argc, char **argv);

static const cmdinfo_t aio_write_cmd = {
        .name           = "aio_write",
        .cfunc          = aio_write_f,
        .argmin         = 2,
        .argmax         = -1,
        .args           = "[-Cq] [-P pattern ] off len [len..]",
        .oneline        = "asynchronously writes a number of bytes",
        .help           = aio_write_help,
};

static int
aio_write_f(int argc, char **argv)
{
        int nr_iov, c;
        int pattern = 0xcd;
        struct aio_ctx *ctx = calloc(1, sizeof(struct aio_ctx));
        BlockDriverAIOCB *acb;

        while ((c = getopt(argc, argv, "CqP:")) != EOF) {
                switch (c) {
                case 'C':
                        ctx->Cflag = 1;
                        break;
                case 'q':
                        ctx->qflag = 1;
                        break;
                case 'P':
                        pattern = parse_pattern(optarg);
                        if (pattern < 0)
                                return 0;
                        break;
                default:
                        free(ctx);
                        return command_usage(&aio_write_cmd);
                }
        }

        if (optind > argc - 2) {
                free(ctx);
                return command_usage(&aio_write_cmd);
        }

        ctx->offset = cvtnum(argv[optind]);
        if (ctx->offset < 0) {
                printf("non-numeric length argument -- %s\n", argv[optind]);
                free(ctx);
                return 0;
        }
        optind++;

        if (ctx->offset & 0x1ff) {
                printf("offset %" PRId64 " is not sector aligned\n",
                       ctx->offset);
                free(ctx);
                return 0;
        }

        nr_iov = argc - optind;
        ctx->buf = create_iovec(&ctx->qiov, &argv[optind], nr_iov, pattern);

        gettimeofday(&ctx->t1, NULL);
        acb = bdrv_aio_writev(bs, ctx->offset >> 9, &ctx->qiov,
                              ctx->qiov.size >> 9, aio_write_done, ctx);
        if (!acb) {
                free(ctx->buf);
                free(ctx);
                return -EIO;
        }

        return 0;
}

static int
aio_flush_f(int argc, char **argv)
{
        qemu_aio_flush();
        return 0;
}

static const cmdinfo_t aio_flush_cmd = {
        .name           = "aio_flush",
        .cfunc          = aio_flush_f,
        .oneline        = "completes all outstanding aio requests"
};

static int
flush_f(int argc, char **argv)
{
        bdrv_flush(bs);
        return 0;
}

static const cmdinfo_t flush_cmd = {
        .name           = "flush",
        .altname        = "f",
        .cfunc          = flush_f,
        .oneline        = "flush all in-core file state to disk",
};

static int
truncate_f(int argc, char **argv)
{
        int64_t offset;
        int ret;

        offset = cvtnum(argv[1]);
        if (offset < 0) {
                printf("non-numeric truncate argument -- %s\n", argv[1]);
                return 0;
        }

        ret = bdrv_truncate(bs, offset);
        if (ret < 0) {
                printf("truncate: %s\n", strerror(-ret));
                return 0;
        }

        return 0;
}

static const cmdinfo_t truncate_cmd = {
        .name           = "truncate",
        .altname        = "t",
        .cfunc          = truncate_f,
        .argmin         = 1,
        .argmax         = 1,
        .args           = "off",
        .oneline        = "truncates the current file at the given offset",
};

static int
length_f(int argc, char **argv)
{
        int64_t size;
        char s1[64];

        size = bdrv_getlength(bs);
        if (size < 0) {
                printf("getlength: %s\n", strerror(-size));
                return 0;
        }

        cvtstr(size, s1, sizeof(s1));
        printf("%s\n", s1);
        return 0;
}


static const cmdinfo_t length_cmd = {
        .name           = "length",
        .altname        = "l",
        .cfunc          = length_f,
        .oneline        = "gets the length of the current file",
};


static int
info_f(int argc, char **argv)
{
        BlockDriverInfo bdi;
        char s1[64], s2[64];
        int ret;

        if (bs->drv && bs->drv->format_name)
                printf("format name: %s\n", bs->drv->format_name);
        if (bs->drv && bs->drv->protocol_name)
                printf("format name: %s\n", bs->drv->protocol_name);

        ret = bdrv_get_info(bs, &bdi);
        if (ret)
                return 0;

        cvtstr(bdi.cluster_size, s1, sizeof(s1));
        cvtstr(bdi.vm_state_offset, s2, sizeof(s2));

        printf("cluster size: %s\n", s1);
        printf("vm state offset: %s\n", s2);

        return 0;
}



static const cmdinfo_t info_cmd = {
        .name           = "info",
        .altname        = "i",
        .cfunc          = info_f,
        .oneline        = "prints information about the current file",
};

static void
discard_help(void)
{
        printf(
"\n"
" discards a range of bytes from the given offset\n"
"\n"
" Example:\n"
" 'discard 512 1k' - discards 1 kilobyte from 512 bytes into the file\n"
"\n"
" Discards a segment of the currently open file.\n"
" -C, -- report statistics in a machine parsable format\n"
" -q, -- quite mode, do not show I/O statistics\n"
"\n");
}

static int discard_f(int argc, char **argv);

static const cmdinfo_t discard_cmd = {
        .name           = "discard",
        .altname        = "d",
        .cfunc          = discard_f,
        .argmin         = 2,
        .argmax         = -1,
        .args           = "[-Cq] off len",
        .oneline        = "discards a number of bytes at a specified offset",
        .help           = discard_help,
};

static int
discard_f(int argc, char **argv)
{
        struct timeval t1, t2;
        int Cflag = 0, qflag = 0;
        int c, ret;
        int64_t offset;
        int count;

        while ((c = getopt(argc, argv, "Cq")) != EOF) {
                switch (c) {
                case 'C':
                        Cflag = 1;
                        break;
                case 'q':
                        qflag = 1;
                        break;
                default:
                        return command_usage(&discard_cmd);
                }
        }

        if (optind != argc - 2) {
                return command_usage(&discard_cmd);
        }

        offset = cvtnum(argv[optind]);
        if (offset < 0) {
                printf("non-numeric length argument -- %s\n", argv[optind]);
                return 0;
        }

        optind++;
        count = cvtnum(argv[optind]);
        if (count < 0) {
                printf("non-numeric length argument -- %s\n", argv[optind]);
                return 0;
        }

        gettimeofday(&t1, NULL);
        ret = bdrv_discard(bs, offset, count);
        gettimeofday(&t2, NULL);

        if (ret < 0) {
                printf("discard failed: %s\n", strerror(-ret));
                goto out;
        }

        /* Finally, report back -- -C gives a parsable format */
        if (!qflag) {
                t2 = tsub(t2, t1);
                print_report("discard", &t2, offset, count, count, 1, Cflag);
        }

out:
        return 0;
}

static int
alloc_f(int argc, char **argv)
{
        int64_t offset;
        int nb_sectors, remaining;
        char s1[64];
        int num, sum_alloc;
        int ret;

        offset = cvtnum(argv[1]);
        if (offset & 0x1ff) {
                printf("offset %" PRId64 " is not sector aligned\n",
                       offset);
                return 0;
        }

        if (argc == 3)
                nb_sectors = cvtnum(argv[2]);
        else
                nb_sectors = 1;

        remaining = nb_sectors;
        sum_alloc = 0;
        while (remaining) {
                ret = bdrv_is_allocated(bs, offset >> 9, nb_sectors, &num);
                remaining -= num;
                if (ret) {
                        sum_alloc += num;
                }
        }

        cvtstr(offset, s1, sizeof(s1));

        printf("%d/%d sectors allocated at offset %s\n",
               sum_alloc, nb_sectors, s1);
        return 0;
}

static const cmdinfo_t alloc_cmd = {
        .name           = "alloc",
        .altname        = "a",
        .argmin         = 1,
        .argmax         = 2,
        .cfunc          = alloc_f,
        .args           = "off [sectors]",
        .oneline        = "checks if a sector is present in the file",
};

static int
map_f(int argc, char **argv)
{
        int64_t offset;
        int64_t nb_sectors;
        char s1[64];
        int num, num_checked;
        int ret;
        const char *retstr;

        offset = 0;
        nb_sectors = bs->total_sectors;

        do {
                num_checked = MIN(nb_sectors, INT_MAX);
                ret = bdrv_is_allocated(bs, offset, num_checked, &num);
                retstr = ret ? "    allocated" : "not allocated";
                cvtstr(offset << 9ULL, s1, sizeof(s1));
                printf("[% 24" PRId64 "] % 8d/% 8d sectors %s at offset %s (%d)\n",
                                offset << 9ULL, num, num_checked, retstr, s1, ret);

                offset += num;
                nb_sectors -= num;
        } while(offset < bs->total_sectors);

        return 0;
}

static const cmdinfo_t map_cmd = {
       .name           = "map",
       .argmin         = 0,
       .argmax         = 0,
       .cfunc          = map_f,
       .args           = "",
       .oneline        = "prints the allocated areas of a file",
};


static int
close_f(int argc, char **argv)
{
        bdrv_close(bs);
        bs = 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, int growable)
{
        if (bs) {
                fprintf(stderr, "file open already, try 'help close'\n");
                return 1;
        }

        if (growable) {
                if (bdrv_file_open(&bs, name, flags)) {
                        fprintf(stderr, "%s: can't open device %s\n", progname, name);
                        return 1;
                }
        } else {
                bs = bdrv_new("hda");

                if (bdrv_open(bs, name, flags, NULL) < 0) {
                        fprintf(stderr, "%s: can't open device %s\n", progname, name);
                        bs = NULL;
                        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"
" -g, -- allow file to grow (only applies to protocols)"
"\n");
}

static int open_f(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] [path]",
        .oneline        = "open the file specified by path",
        .help           = open_help,
};

static int
open_f(int argc, char **argv)
{
        int flags = 0;
        int readonly = 0;
        int growable = 0;
        int c;

        while ((c = getopt(argc, argv, "snrg")) != EOF) {
                switch (c) {
                case 's':
                        flags |= BDRV_O_SNAPSHOT;
                        break;
                case 'n':
                        flags |= BDRV_O_NOCACHE;
                        break;
                case 'r':
                        readonly = 1;
                        break;
                case 'g':
                        growable = 1;
                        break;
                default:
                        return command_usage(&open_cmd);
                }
        }

        if (!readonly) {
            flags |= BDRV_O_RDWR;
        }

        if (optind != argc - 1)
                return command_usage(&open_cmd);

        return openfile(argv[optind], flags, growable);
}

static int
init_args_command(
        int     index)
{
        /* only one device allowed so far */
        if (index >= 1)
                return 0;
        return ++index;
}

static int
init_check_command(
        const cmdinfo_t *ct)
{
        if (ct->flags & CMD_FLAG_GLOBAL)
                return 1;
        if (!(ct->flags & CMD_NOFILE_OK) && !bs) {
                fprintf(stderr, "no file open, try 'help open'\n");
                return 0;
        }
        return 1;
}

static void usage(const char *name)
{
        printf(
"Usage: %s [-h] [-V] [-rsnm] [-c cmd] ... [file]\n"
"QEMU Disk exerciser\n"
"\n"
"  -c, --cmd            command to execute\n"
"  -r, --read-only      export read-only\n"
"  -s, --snapshot       use snapshot file\n"
"  -n, --nocache        disable host cache\n"
"  -g, --growable       allow file to grow (only applies to protocols)\n"
"  -m, --misalign       misalign allocations for O_DIRECT\n"
"  -k, --native-aio     use kernel AIO implementation (on Linux only)\n"
"  -h, --help           display this help and exit\n"
"  -V, --version        output version information and exit\n"
"\n",
        name);
}


int main(int argc, char **argv)
{
        int readonly = 0;
        int growable = 0;
        const char *sopt = "hVc:rsnmgk";
        const struct option lopt[] = {
                { "help", 0, NULL, 'h' },
                { "version", 0, NULL, 'V' },
                { "offset", 1, NULL, 'o' },
                { "cmd", 1, NULL, 'c' },
                { "read-only", 0, NULL, 'r' },
                { "snapshot", 0, NULL, 's' },
                { "nocache", 0, NULL, 'n' },
                { "misalign", 0, NULL, 'm' },
                { "growable", 0, NULL, 'g' },
                { "native-aio", 0, NULL, 'k' },
                { NULL, 0, NULL, 0 }
        };
        int c;
        int opt_index = 0;
        int flags = 0;

        progname = basename(argv[0]);

        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;
                        break;
                case 'c':
                        add_user_command(optarg);
                        break;
                case 'r':
                        readonly = 1;
                        break;
                case 'm':
                        misalign = 1;
                        break;
                case 'g':
                        growable = 1;
                        break;
                case 'k':
                        flags |= BDRV_O_NATIVE_AIO;
                        break;
                case 'V':
                        printf("%s version %s\n", progname, VERSION);
                        exit(0);
                case 'h':
                        usage(progname);
                        exit(0);
                default:
                        usage(progname);
                        exit(1);
                }
        }

        if ((argc - optind) > 1) {
                usage(progname);
                exit(1);
        }

        bdrv_init();

        /* initialize commands */
        quit_init();
        help_init();
        add_command(&open_cmd);
        add_command(&close_cmd);
        add_command(&read_cmd);
        add_command(&readv_cmd);
        add_command(&write_cmd);
        add_command(&writev_cmd);
        add_command(&multiwrite_cmd);
        add_command(&aio_read_cmd);
        add_command(&aio_write_cmd);
        add_command(&aio_flush_cmd);
        add_command(&flush_cmd);
        add_command(&truncate_cmd);
        add_command(&length_cmd);
        add_command(&info_cmd);
        add_command(&discard_cmd);
        add_command(&alloc_cmd);
        add_command(&map_cmd);

        add_args_command(init_args_command);
        add_check_command(init_check_command);

        /* open the device */
        if (!readonly) {
            flags |= BDRV_O_RDWR;
        }

        if ((argc - optind) == 1)
                openfile(argv[optind], flags, growable);
        command_loop();

        /*
         * Make sure all outstanding requests get flushed the program exits.
         */
        qemu_aio_flush();

        if (bs)
                bdrv_close(bs);
        return 0;
}