qemu-io: Split off commands to qemu-io-cmds.c

This is the implementation of all qemu-io commands that make sense to be
called from the qemu monitor, i.e. everything except open, close and
quit.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

1 files changed, 1835 insertions, 0 deletions

diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
new file mode 100644
index 0000000..0a3817a
--- /dev/null
+++ b/qemu-io-cmds.c
@@ -0,0 +1,1835 @@
+/*
+ * 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-common.h"
+#include "block/block_int.h"
+#include "cmd.h"
+
+#define CMD_NOFILE_OK   0x01
+
+int qemuio_misalign;
+
+static int64_t cvtnum(const char *s)
+{
+    char *end;
+    return strtosz_suffix(s, &end, STRTOSZ_DEFSUFFIX_B);
+}
+
+/*
+ * 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(BlockDriverState *bs, size_t len, int pattern)
+{
+    void *buf;
+
+    if (qemuio_misalign) {
+        len += MISALIGN_OFFSET;
+    }
+    buf = qemu_blockalign(bs, len);
+    memset(buf, pattern, len);
+    if (qemuio_misalign) {
+        buf += MISALIGN_OFFSET;
+    }
+    return buf;
+}
+
+static void qemu_io_free(void *p)
+{
+    if (qemuio_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(BlockDriverState *bs, QEMUIOVector *qiov, char **argv, int nr_iov,
+             int pattern)
+{
+    size_t *sizes = g_new0(size_t, nr_iov);
+    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(bs, count, pattern);
+
+    for (i = 0; i < nr_iov; i++) {
+        qemu_iovec_add(qiov, p, sizes[i]);
+        p += sizes[i];
+    }
+
+fail:
+    g_free(sizes);
+    return buf;
+}
+
+static int do_read(BlockDriverState *bs, 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(BlockDriverState *bs, 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(BlockDriverState *bs, 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(BlockDriverState *bs, 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;
+}
+
+typedef struct {
+    BlockDriverState *bs;
+    int64_t offset;
+    int count;
+    int *total;
+    int ret;
+    bool done;
+} CoWriteZeroes;
+
+static void coroutine_fn co_write_zeroes_entry(void *opaque)
+{
+    CoWriteZeroes *data = opaque;
+
+    data->ret = bdrv_co_write_zeroes(data->bs, data->offset / BDRV_SECTOR_SIZE,
+                                     data->count / BDRV_SECTOR_SIZE);
+    data->done = true;
+    if (data->ret < 0) {
+        *data->total = data->ret;
+        return;
+    }
+
+    *data->total = data->count;
+}
+
+static int do_co_write_zeroes(BlockDriverState *bs, int64_t offset, int count,
+                              int *total)
+{
+    Coroutine *co;
+    CoWriteZeroes data = {
+        .bs     = bs,
+        .offset = offset,
+        .count  = count,
+        .total  = total,
+        .done   = false,
+    };
+
+    co = qemu_coroutine_create(co_write_zeroes_entry);
+    qemu_coroutine_enter(co, &data);
+    while (!data.done) {
+        qemu_aio_wait();
+    }
+    if (data.ret < 0) {
+        return data.ret;
+    } else {
+        return 1;
+    }
+}
+
+static int do_write_compressed(BlockDriverState *bs, char *buf, int64_t offset,
+                               int count, int *total)
+{
+    int ret;
+
+    ret = bdrv_write_compressed(bs, offset >> 9, (uint8_t *)buf, count >> 9);
+    if (ret < 0) {
+        return ret;
+    }
+    *total = count;
+    return 1;
+}
+
+static int do_load_vmstate(BlockDriverState *bs, 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(BlockDriverState *bs, 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(BlockDriverState *bs, QEMUIOVector *qiov,
+                        int64_t offset, int *total)
+{
+    int async_ret = NOT_DONE;
+
+    bdrv_aio_readv(bs, offset >> 9, qiov, qiov->size >> 9,
+                   aio_rw_done, &async_ret);
+    while (async_ret == NOT_DONE) {
+        main_loop_wait(false);
+    }
+
+    *total = qiov->size;
+    return async_ret < 0 ? async_ret : 1;
+}
+
+static int do_aio_writev(BlockDriverState *bs, QEMUIOVector *qiov,
+                         int64_t offset, int *total)
+{
+    int async_ret = NOT_DONE;
+
+    bdrv_aio_writev(bs, offset >> 9, qiov, qiov->size >> 9,
+                    aio_rw_done, &async_ret);
+    while (async_ret == NOT_DONE) {
+        main_loop_wait(false);
+    }
+
+    *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(BlockDriverState *bs, 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) {
+        main_loop_wait(false);
+    }
+
+    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, -- quiet 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(BlockDriverState *bs, 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(BlockDriverState *bs, 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 verification 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(bs, count, 0xab);
+
+    gettimeofday(&t1, NULL);
+    if (pflag) {
+        cnt = do_pread(bs, buf, offset, count, &total);
+    } else if (bflag) {
+        cnt = do_load_vmstate(bs, buf, offset, count, &total);
+    } else {
+        cnt = do_read(bs, buf, offset, count, &total);
+    }
+    gettimeofday(&t2, NULL);
+
+    if (cnt < 0) {
+        printf("read failed: %s\n", strerror(-cnt));
+        goto out;
+    }
+
+    if (Pflag) {
+        void *cmp_buf = g_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);
+        }
+        g_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, -- quiet mode, do not show I/O statistics\n"
+"\n");
+}
+
+static int readv_f(BlockDriverState *bs, 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(BlockDriverState *bs, 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(bs, &qiov, &argv[optind], nr_iov, 0xab);
+    if (buf == NULL) {
+        return 0;
+    }
+
+    gettimeofday(&t1, NULL);
+    cnt = do_aio_readv(bs, &qiov, offset, &total);
+    gettimeofday(&t2, NULL);
+
+    if (cnt < 0) {
+        printf("readv failed: %s\n", strerror(-cnt));
+        goto out;
+    }
+
+    if (Pflag) {
+        void *cmp_buf = g_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);
+        }
+        g_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_iovec_destroy(&qiov);
+    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"
+" -c, -- write compressed data with bdrv_write_compressed\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, -- quiet mode, do not show I/O statistics\n"
+" -z, -- write zeroes using bdrv_co_write_zeroes\n"
+"\n");
+}
+
+static int write_f(BlockDriverState *bs, int argc, char **argv);
+
+static const cmdinfo_t write_cmd = {
+    .name       = "write",
+    .altname    = "w",
+    .cfunc      = write_f,
+    .argmin     = 2,
+    .argmax     = -1,
+    .args       = "[-bcCpqz] [-P pattern ] off len",
+    .oneline    = "writes a number of bytes at a specified offset",
+    .help       = write_help,
+};
+
+static int write_f(BlockDriverState *bs, int argc, char **argv)
+{
+    struct timeval t1, t2;
+    int Cflag = 0, pflag = 0, qflag = 0, bflag = 0, Pflag = 0, zflag = 0;
+    int cflag = 0;
+    int c, cnt;
+    char *buf = NULL;
+    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, "bcCpP:qz")) != EOF) {
+        switch (c) {
+        case 'b':
+            bflag = 1;
+            break;
+        case 'c':
+            cflag = 1;
+            break;
+        case 'C':
+            Cflag = 1;
+            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 'z':
+            zflag = 1;
+            break;
+        default:
+            return command_usage(&write_cmd);
+        }
+    }
+
+    if (optind != argc - 2) {
+        return command_usage(&write_cmd);
+    }
+
+    if (bflag + pflag + zflag > 1) {
+        printf("-b, -p, or -z cannot be specified at the same time\n");
+        return 0;
+    }
+
+    if (zflag && Pflag) {
+        printf("-z 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;
+        }
+    }
+
+    if (!zflag) {
+        buf = qemu_io_alloc(bs, count, pattern);
+    }
+
+    gettimeofday(&t1, NULL);
+    if (pflag) {
+        cnt = do_pwrite(bs, buf, offset, count, &total);
+    } else if (bflag) {
+        cnt = do_save_vmstate(bs, buf, offset, count, &total);
+    } else if (zflag) {
+        cnt = do_co_write_zeroes(bs, offset, count, &total);
+    } else if (cflag) {
+        cnt = do_write_compressed(bs, buf, offset, count, &total);
+    } else {
+        cnt = do_write(bs, 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:
+    if (!zflag) {
+        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, -- quiet mode, do not show I/O statistics\n"
+"\n");
+}
+
+static int writev_f(BlockDriverState *bs, 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(BlockDriverState *bs, 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(bs, &qiov, &argv[optind], nr_iov, pattern);
+    if (buf == NULL) {
+        return 0;
+    }
+
+    gettimeofday(&t1, NULL);
+    cnt = do_aio_writev(bs, &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_iovec_destroy(&qiov);
+    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(BlockDriverState *bs, 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(BlockDriverState *bs, 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 = g_malloc0(nr_reqs * sizeof(*reqs));
+    buf = g_malloc0(nr_reqs * sizeof(*buf));
+    qiovs = g_malloc(nr_reqs * sizeof(*qiovs));
+
+    for (i = 0; i < nr_reqs && optind < argc; 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]);
+            goto out;
+        }
+        optind++;
+
+        if (offset & 0x1ff) {
+            printf("offset %lld is not sector aligned\n",
+                   (long long)offset);
+            goto out;
+        }
+
+        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 */
+        buf[i] = create_iovec(bs, &qiovs[i], &argv[optind], nr_iov, pattern);
+        if (buf[i] == NULL) {
+            goto out;
+        }
+
+        reqs[i].qiov = &qiovs[i];
+        reqs[i].sector = offset >> 9;
+        reqs[i].nb_sectors = reqs[i].qiov->size >> 9;
+
+        optind = j + 1;
+
+        pattern++;
+    }
+
+    /* If there were empty requests at the end, ignore them */
+    nr_reqs = i;
+
+    gettimeofday(&t1, NULL);
+    cnt = do_aio_multiwrite(bs, 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]);
+        if (reqs[i].qiov != NULL) {
+            qemu_iovec_destroy(&qiovs[i]);
+        }
+    }
+    g_free(buf);
+    g_free(reqs);
+    g_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);
+    qemu_iovec_destroy(&ctx->qiov);
+    g_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 = g_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);
+        }
+        g_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);
+    qemu_iovec_destroy(&ctx->qiov);
+    g_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, -- quiet mode, do not show I/O statistics\n"
+"\n");
+}
+
+static int aio_read_f(BlockDriverState *bs, 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(BlockDriverState *bs, int argc, char **argv)
+{
+    int nr_iov, c;
+    struct aio_ctx *ctx = g_new0(struct aio_ctx, 1);
+
+    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) {
+                g_free(ctx);
+                return 0;
+            }
+            break;
+        case 'q':
+            ctx->qflag = 1;
+            break;
+        case 'v':
+            ctx->vflag = 1;
+            break;
+        default:
+            g_free(ctx);
+            return command_usage(&aio_read_cmd);
+        }
+    }
+
+    if (optind > argc - 2) {
+        g_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]);
+        g_free(ctx);
+        return 0;
+    }
+    optind++;
+
+    if (ctx->offset & 0x1ff) {
+        printf("offset %" PRId64 " is not sector aligned\n",
+               ctx->offset);
+        g_free(ctx);
+        return 0;
+    }
+
+    nr_iov = argc - optind;
+    ctx->buf = create_iovec(bs, &ctx->qiov, &argv[optind], nr_iov, 0xab);
+    if (ctx->buf == NULL) {
+        g_free(ctx);
+        return 0;
+    }
+
+    gettimeofday(&ctx->t1, NULL);
+    bdrv_aio_readv(bs, ctx->offset >> 9, &ctx->qiov,
+                   ctx->qiov.size >> 9, aio_read_done, ctx);
+    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, -- quiet mode, do not show I/O statistics\n"
+"\n");
+}
+
+static int aio_write_f(BlockDriverState *bs, 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(BlockDriverState *bs, int argc, char **argv)
+{
+    int nr_iov, c;
+    int pattern = 0xcd;
+    struct aio_ctx *ctx = g_new0(struct aio_ctx, 1);
+
+    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) {
+                g_free(ctx);
+                return 0;
+            }
+            break;
+        default:
+            g_free(ctx);
+            return command_usage(&aio_write_cmd);
+        }
+    }
+
+    if (optind > argc - 2) {
+        g_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]);
+        g_free(ctx);
+        return 0;
+    }
+    optind++;
+
+    if (ctx->offset & 0x1ff) {
+        printf("offset %" PRId64 " is not sector aligned\n",
+               ctx->offset);
+        g_free(ctx);
+        return 0;
+    }
+
+    nr_iov = argc - optind;
+    ctx->buf = create_iovec(bs, &ctx->qiov, &argv[optind], nr_iov, pattern);
+    if (ctx->buf == NULL) {
+        g_free(ctx);
+        return 0;
+    }
+
+    gettimeofday(&ctx->t1, NULL);
+    bdrv_aio_writev(bs, ctx->offset >> 9, &ctx->qiov,
+                    ctx->qiov.size >> 9, aio_write_done, ctx);
+    return 0;
+}
+
+static int aio_flush_f(BlockDriverState *bs, int argc, char **argv)
+{
+    bdrv_drain_all();
+    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(BlockDriverState *bs, 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(BlockDriverState *bs, 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(BlockDriverState *bs, 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(BlockDriverState *bs, 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, -- quiet mode, do not show I/O statistics\n"
+"\n");
+}
+
+static int discard_f(BlockDriverState *bs, 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(BlockDriverState *bs, 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 >> BDRV_SECTOR_BITS,
+                       count >> BDRV_SECTOR_BITS);
+    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(BlockDriverState *bs, int argc, char **argv)
+{
+    int64_t offset, sector_num;
+    int nb_sectors, remaining;
+    char s1[64];
+    int num, sum_alloc;
+    int ret;
+
+    offset = cvtnum(argv[1]);
+    if (offset < 0) {
+        printf("non-numeric offset argument -- %s\n", argv[1]);
+        return 0;
+    } else if (offset & 0x1ff) {
+        printf("offset %" PRId64 " is not sector aligned\n",
+               offset);
+        return 0;
+    }
+
+    if (argc == 3) {
+        nb_sectors = cvtnum(argv[2]);
+        if (nb_sectors < 0) {
+            printf("non-numeric length argument -- %s\n", argv[2]);
+            return 0;
+        }
+    } else {
+        nb_sectors = 1;
+    }
+
+    remaining = nb_sectors;
+    sum_alloc = 0;
+    sector_num = offset >> 9;
+    while (remaining) {
+        ret = bdrv_is_allocated(bs, sector_num, remaining, &num);
+        sector_num += num;
+        remaining -= num;
+        if (ret) {
+            sum_alloc += num;
+        }
+        if (num == 0) {
+            nb_sectors -= remaining;
+            remaining = 0;
+        }
+    }
+
+    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_is_allocated(BlockDriverState *bs, int64_t sector_num,
+                            int64_t nb_sectors, int64_t *pnum)
+{
+    int num, num_checked;
+    int ret, firstret;
+
+    num_checked = MIN(nb_sectors, INT_MAX);
+    ret = bdrv_is_allocated(bs, sector_num, num_checked, &num);
+    if (ret < 0) {
+        return ret;
+    }
+
+    firstret = ret;
+    *pnum = num;
+
+    while (nb_sectors > 0 && ret == firstret) {
+        sector_num += num;
+        nb_sectors -= num;
+
+        num_checked = MIN(nb_sectors, INT_MAX);
+        ret = bdrv_is_allocated(bs, sector_num, num_checked, &num);
+        if (ret == firstret) {
+            *pnum += num;
+        } else {
+            break;
+        }
+    }
+
+    return firstret;
+}
+
+static int map_f(BlockDriverState *bs, int argc, char **argv)
+{
+    int64_t offset;
+    int64_t nb_sectors;
+    char s1[64];
+    int64_t num;
+    int ret;
+    const char *retstr;
+
+    offset = 0;
+    nb_sectors = bs->total_sectors;
+
+    do {
+        ret = map_is_allocated(bs, offset, nb_sectors, &num);
+        if (ret < 0) {
+            error_report("Failed to get allocation status: %s", strerror(-ret));
+            return 0;
+        }
+
+        retstr = ret ? "    allocated" : "not allocated";
+        cvtstr(offset << 9ULL, s1, sizeof(s1));
+        printf("[% 24" PRId64 "] % 8" PRId64 "/% 8" PRId64 " sectors %s "
+               "at offset %s (%d)\n",
+               offset << 9ULL, num, nb_sectors, 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 break_f(BlockDriverState *bs, int argc, char **argv)
+{
+    int ret;
+
+    ret = bdrv_debug_breakpoint(bs, argv[1], argv[2]);
+    if (ret < 0) {
+        printf("Could not set breakpoint: %s\n", strerror(-ret));
+    }
+
+    return 0;
+}
+
+static const cmdinfo_t break_cmd = {
+       .name           = "break",
+       .argmin         = 2,
+       .argmax         = 2,
+       .cfunc          = break_f,
+       .args           = "event tag",
+       .oneline        = "sets a breakpoint on event and tags the stopped "
+                         "request as tag",
+};
+
+static int resume_f(BlockDriverState *bs, int argc, char **argv)
+{
+    int ret;
+
+    ret = bdrv_debug_resume(bs, argv[1]);
+    if (ret < 0) {
+        printf("Could not resume request: %s\n", strerror(-ret));
+    }
+
+    return 0;
+}
+
+static const cmdinfo_t resume_cmd = {
+       .name           = "resume",
+       .argmin         = 1,
+       .argmax         = 1,
+       .cfunc          = resume_f,
+       .args           = "tag",
+       .oneline        = "resumes the request tagged as tag",
+};
+
+static int wait_break_f(BlockDriverState *bs, int argc, char **argv)
+{
+    while (!bdrv_debug_is_suspended(bs, argv[1])) {
+        qemu_aio_wait();
+    }
+
+    return 0;
+}
+
+static const cmdinfo_t wait_break_cmd = {
+       .name           = "wait_break",
+       .argmin         = 1,
+       .argmax         = 1,
+       .cfunc          = wait_break_f,
+       .args           = "tag",
+       .oneline        = "waits for the suspension of a request",
+};
+
+static int abort_f(BlockDriverState *bs, int argc, char **argv)
+{
+    abort();
+}
+
+static const cmdinfo_t abort_cmd = {
+       .name           = "abort",
+       .cfunc          = abort_f,
+       .flags          = CMD_NOFILE_OK,
+       .oneline        = "simulate a program crash using abort(3)",
+};
+
+static int init_check_command(BlockDriverState *bs, 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 __attribute((constructor)) init_qemuio_commands(void)
+{
+    /* initialize commands */
+    help_init();
+    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_command(&break_cmd);
+    add_command(&resume_cmd);
+    add_command(&wait_break_cmd);
+    add_command(&abort_cmd);
+
+    add_check_command(init_check_command);
+}