Merge remote-tracking branch 'kwolf/for-anthony' into staging

* kwolf/for-anthony:
  block: Don't forget to delete temporary file
  Don't require encryption password for 'qemu-img info' command
  qemu-img: Add json output option to the info command.
  qapi: Add SnapshotInfo and ImageInfo.
  ahci: properly reset PxCMD on HBA reset
  block: fix block tray status
  vdi: Fix warning from clang
  block/curl: Fix wrong free statement
  ide: Fix error messages from static code analysis (no real error)
  ATAPI: STARTSTOPUNIT only eject/load media if powercondition is 0
  sheepdog: fix savevm and loadvm

Makefile

@@ -157,7 +157,8 @@ tools-obj-y = $(oslib-obj-y) $(trace-obj-y) qemu-tool.o qemu-timer.o \
 	iohandler.o cutils.o iov.o async.o
 tools-obj-$(CONFIG_POSIX) += compatfd.o
 
-qemu-img$(EXESUF): qemu-img.o $(tools-obj-y) $(block-obj-y)
+qemu-img$(EXESUF): qemu-img.o $(tools-obj-y) $(block-obj-y) $(qapi-obj-y) \
+                              qapi-visit.o qapi-types.o
 qemu-nbd$(EXESUF): qemu-nbd.o $(tools-obj-y) $(block-obj-y)
 qemu-io$(EXESUF): qemu-io.o cmd.o $(tools-obj-y) $(block-obj-y)
 

block.c

@@ -433,7 +433,11 @@ int get_tmp_filename(char *filename, int size)
         return -EOVERFLOW;
     }
     fd = mkstemp(filename);
-    if (fd < 0 || close(fd)) {
+    if (fd < 0) {
+        return -errno;
+    }
+    if (close(fd) != 0) {
+        unlink(filename);
         return -errno;
     }
     return 0;
@@ -897,10 +901,10 @@ void bdrv_close(BlockDriverState *bs)
             bdrv_delete(bs->file);
             bs->file = NULL;
         }
-
-        bdrv_dev_change_media_cb(bs, false);
     }
 
+    bdrv_dev_change_media_cb(bs, false);
+
     /*throttling disk I/O limits*/
     if (bs->io_limits_enabled) {
         bdrv_io_limits_disable(bs);

block/curl.c

@@ -542,8 +542,7 @@ static void curl_close(BlockDriverState *bs)
     }
     if (s->multi)
         curl_multi_cleanup(s->multi);
-    if (s->url)
-        free(s->url);
+    g_free(s->url);
 }
 
 static int64_t curl_getlength(BlockDriverState *bs)

block/sheepdog.c

@@ -1986,7 +1986,7 @@ static int do_load_save_vmstate(BDRVSheepdogState *s, uint8_t *data,
         vdi_index = pos / SD_DATA_OBJ_SIZE;
         offset = pos % SD_DATA_OBJ_SIZE;
 
-        data_len = MIN(remaining, SD_DATA_OBJ_SIZE);
+        data_len = MIN(remaining, SD_DATA_OBJ_SIZE - offset);
 
         vmstate_oid = vid_to_vmstate_oid(s->inode.vdi_id, vdi_index);
 
@@ -2007,6 +2007,7 @@ static int do_load_save_vmstate(BDRVSheepdogState *s, uint8_t *data,
         }
 
         pos += data_len;
+        data += data_len;
         remaining -= data_len;
     }
     ret = size;

block/vdi.c

@@ -628,7 +628,6 @@ static int vdi_create(const char *filename, QEMUOptionParameter *options)
     VdiHeader header;
     size_t i;
     size_t bmap_size;
-    uint32_t *bmap;
 
     logout("\n");
 
@@ -693,21 +692,21 @@ static int vdi_create(const char *filename, QEMUOptionParameter *options)
         result = -errno;
     }
 
-    bmap = NULL;
     if (bmap_size > 0) {
-        bmap = (uint32_t *)g_malloc0(bmap_size);
-    }
-    for (i = 0; i < blocks; i++) {
-        if (image_type == VDI_TYPE_STATIC) {
-            bmap[i] = i;
-        } else {
-            bmap[i] = VDI_UNALLOCATED;
+        uint32_t *bmap = g_malloc0(bmap_size);
+        for (i = 0; i < blocks; i++) {
+            if (image_type == VDI_TYPE_STATIC) {
+                bmap[i] = i;
+            } else {
+                bmap[i] = VDI_UNALLOCATED;
+            }
         }
+        if (write(fd, bmap, bmap_size) < 0) {
+            result = -errno;
+        }
+        g_free(bmap);
     }
-    if (write(fd, bmap, bmap_size) < 0) {
-        result = -errno;
-    }
-    g_free(bmap);
+
     if (image_type == VDI_TYPE_STATIC) {
         if (ftruncate(fd, sizeof(header) + bmap_size + blocks * block_size)) {
             result = -errno;

hw/ide/ahci.c

@@ -1175,7 +1175,6 @@ void ahci_init(AHCIState *s, DeviceState *qdev, DMAContext *dma, int ports)
         ad->port_no = i;
         ad->port.dma = &ad->dma;
         ad->port.dma->ops = &ahci_dma_ops;
-        ad->port_regs.cmd = PORT_CMD_SPIN_UP | PORT_CMD_POWER_ON;
     }
 }
 
@@ -1199,6 +1198,7 @@ void ahci_reset(AHCIState *s)
         pr->irq_stat = 0;
         pr->irq_mask = 0;
         pr->scr_ctl = 0;
+        pr->cmd = PORT_CMD_SPIN_UP | PORT_CMD_POWER_ON;
         ahci_reset_port(s, i);
     }
 }

hw/ide/atapi.c

@@ -875,6 +875,12 @@ static void cmd_start_stop_unit(IDEState *s, uint8_t* buf)
     int sense;
     bool start = buf[4] & 1;
     bool loej = buf[4] & 2;     /* load on start, eject on !start */
+    int pwrcnd = buf[4] & 0xf0;
+
+    if (pwrcnd) {
+        /* eject/load only happens for power condition == 0 */
+        return;
+    }
 
     if (loej) {
         if (!start && !s->tray_open && s->tray_locked) {

hw/ide/core.c

@@ -53,8 +53,6 @@ static const int smart_attributes[][12] = {
     { 0x0c, 0x03, 0x00, 0x64, 0x64, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
     /* airflow-temperature-celsius */
     { 190,  0x03, 0x00, 0x45, 0x45, 0x1f, 0x00, 0x1f, 0x1f, 0x00, 0x00, 0x32},
-    /* end of list */
-    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}
 };
 
 static int ide_handle_rw_error(IDEState *s, int error, int op);
@@ -1468,9 +1466,7 @@ void ide_exec_cmd(IDEBus *bus, uint32_t val)
 	case SMART_READ_THRESH:
 		memset(s->io_buffer, 0, 0x200);
 		s->io_buffer[0] = 0x01; /* smart struct version */
-		for (n=0; n<30; n++) {
-		if (smart_attributes[n][0] == 0)
-			break;
+		for (n = 0; n < ARRAY_SIZE(smart_attributes); n++) {
 		s->io_buffer[2+0+(n*12)] = smart_attributes[n][0];
 		s->io_buffer[2+1+(n*12)] = smart_attributes[n][11];
 		}
@@ -1484,10 +1480,7 @@ void ide_exec_cmd(IDEBus *bus, uint32_t val)
 	case SMART_READ_DATA:
 		memset(s->io_buffer, 0, 0x200);
 		s->io_buffer[0] = 0x01; /* smart struct version */
-		for (n=0; n<30; n++) {
-		    if (smart_attributes[n][0] == 0) {
-			break;
-		    }
+		for (n = 0; n < ARRAY_SIZE(smart_attributes); n++) {
 		    int i;
 		    for(i = 0; i < 11; i++) {
 			s->io_buffer[2+i+(n*12)] = smart_attributes[n][i];

qapi-schema.json

@@ -155,6 +155,70 @@
             'postmigrate', 'prelaunch', 'finish-migrate', 'restore-vm',
             'running', 'save-vm', 'shutdown', 'suspended', 'watchdog' ] }
 
+##
+# @SnapshotInfo
+#
+# @id: unique snapshot id
+#
+# @name: user chosen name
+#
+# @vm-state-size: size of the VM state
+#
+# @date-sec: UTC date of the snapshot in seconds
+#
+# @date-nsec: fractional part in nano seconds to be used with date-sec
+#
+# @vm-clock-sec: VM clock relative to boot in seconds
+#
+# @vm-clock-nsec: fractional part in nano seconds to be used with vm-clock-sec
+#
+# Since: 1.3
+#
+##
+
+{ 'type': 'SnapshotInfo',
+  'data': { 'id': 'str', 'name': 'str', 'vm-state-size': 'int',
+            'date-sec': 'int', 'date-nsec': 'int',
+            'vm-clock-sec': 'int', 'vm-clock-nsec': 'int' } }
+
+##
+# @ImageInfo:
+#
+# Information about a QEMU image file
+#
+# @filename: name of the image file
+#
+# @format: format of the image file
+#
+# @virtual-size: maximum capacity in bytes of the image
+#
+# @actual-size: #optional actual size on disk in bytes of the image
+#
+# @dirty-flag: #optional true if image is not cleanly closed
+#
+# @cluster-size: #optional size of a cluster in bytes
+#
+# @encrypted: #optional true if the image is encrypted
+#
+# @backing-filename: #optional name of the backing file
+#
+# @full-backing-filename: #optional full path of the backing file
+#
+# @backing-filename-format: #optional the format of the backing file
+#
+# @snapshots: #optional list of VM snapshots
+#
+# Since: 1.3
+#
+##
+
+{ 'type': 'ImageInfo',
+  'data': {'filename': 'str', 'format': 'str', '*dirty-flag': 'bool',
+           '*actual-size': 'int', 'virtual-size': 'int',
+           '*cluster-size': 'int', '*encrypted': 'bool',
+           '*backing-filename': 'str', '*full-backing-filename': 'str',
+           '*backing-filename-format': 'str', '*snapshots': ['SnapshotInfo'] } }
+
 ##
 # @StatusInfo:
 #

qemu-img-cmds.hx

@@ -34,9 +34,9 @@ STEXI
 ETEXI
 
 DEF("info", img_info,
-    "info [-f fmt] filename")
+    "info [-f fmt] [--output=ofmt] filename")
 STEXI
-@item info [-f @var{fmt}] @var{filename}
+@item info [-f @var{fmt}] [--output=@var{ofmt}] @var{filename}
 ETEXI
 
 DEF("snapshot", img_snapshot,

qemu-img.c

@@ -21,12 +21,16 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+#include "qapi-visit.h"
+#include "qapi/qmp-output-visitor.h"
+#include "qjson.h"
 #include "qemu-common.h"
 #include "qemu-option.h"
 #include "qemu-error.h"
 #include "osdep.h"
 #include "sysemu.h"
 #include "block_int.h"
+#include <getopt.h>
 #include <stdio.h>
 
 #ifdef _WIN32
@@ -84,6 +88,7 @@ static void help(void)
            "  '-p' show progress of command (only certain commands)\n"
            "  '-S' indicates the consecutive number of bytes that must contain only zeros\n"
            "       for qemu-img to create a sparse image during conversion\n"
+           "  '--output' takes the format in which the output must be done (human or json)\n"
            "\n"
            "Parameters to check subcommand:\n"
            "  '-r' tries to repair any inconsistencies that are found during the check.\n"
@@ -221,7 +226,8 @@ static int print_block_option_help(const char *filename, const char *fmt)
 
 static BlockDriverState *bdrv_new_open(const char *filename,
                                        const char *fmt,
-                                       int flags)
+                                       int flags,
+                                       bool require_io)
 {
     BlockDriverState *bs;
     BlockDriver *drv;
@@ -246,7 +252,7 @@ static BlockDriverState *bdrv_new_open(const char *filename,
         goto fail;
     }
 
-    if (bdrv_is_encrypted(bs)) {
+    if (bdrv_is_encrypted(bs) && require_io) {
         printf("Disk image '%s' is encrypted.\n", filename);
         if (read_password(password, sizeof(password)) < 0) {
             error_report("No password given");
@@ -413,7 +419,7 @@ static int img_check(int argc, char **argv)
     }
     filename = argv[optind++];
 
-    bs = bdrv_new_open(filename, fmt, flags);
+    bs = bdrv_new_open(filename, fmt, flags, true);
     if (!bs) {
         return 1;
     }
@@ -520,7 +526,7 @@ static int img_commit(int argc, char **argv)
         return -1;
     }
 
-    bs = bdrv_new_open(filename, fmt, flags);
+    bs = bdrv_new_open(filename, fmt, flags, true);
     if (!bs) {
         return 1;
     }
@@ -762,7 +768,7 @@ static int img_convert(int argc, char **argv)
 
     total_sectors = 0;
     for (bs_i = 0; bs_i < bs_n; bs_i++) {
-        bs[bs_i] = bdrv_new_open(argv[optind + bs_i], fmt, BDRV_O_FLAGS);
+        bs[bs_i] = bdrv_new_open(argv[optind + bs_i], fmt, BDRV_O_FLAGS, true);
         if (!bs[bs_i]) {
             error_report("Could not open '%s'", argv[optind + bs_i]);
             ret = -1;
@@ -881,7 +887,7 @@ static int img_convert(int argc, char **argv)
         return -1;
     }
 
-    out_bs = bdrv_new_open(out_filename, out_fmt, flags);
+    out_bs = bdrv_new_open(out_filename, out_fmt, flags, true);
     if (!out_bs) {
         ret = -1;
         goto out;
@@ -1102,21 +1108,174 @@ static void dump_snapshots(BlockDriverState *bs)
     g_free(sn_tab);
 }
 
-static int img_info(int argc, char **argv)
+static void collect_snapshots(BlockDriverState *bs , ImageInfo *info)
+{
+    int i, sn_count;
+    QEMUSnapshotInfo *sn_tab = NULL;
+    SnapshotInfoList *info_list, *cur_item = NULL;
+    sn_count = bdrv_snapshot_list(bs, &sn_tab);
+
+    for (i = 0; i < sn_count; i++) {
+        info->has_snapshots = true;
+        info_list = g_new0(SnapshotInfoList, 1);
+
+        info_list->value                = g_new0(SnapshotInfo, 1);
+        info_list->value->id            = g_strdup(sn_tab[i].id_str);
+        info_list->value->name          = g_strdup(sn_tab[i].name);
+        info_list->value->vm_state_size = sn_tab[i].vm_state_size;
+        info_list->value->date_sec      = sn_tab[i].date_sec;
+        info_list->value->date_nsec     = sn_tab[i].date_nsec;
+        info_list->value->vm_clock_sec  = sn_tab[i].vm_clock_nsec / 1000000000;
+        info_list->value->vm_clock_nsec = sn_tab[i].vm_clock_nsec % 1000000000;
+
+        /* XXX: waiting for the qapi to support qemu-queue.h types */
+        if (!cur_item) {
+            info->snapshots = cur_item = info_list;
+        } else {
+            cur_item->next = info_list;
+            cur_item = info_list;
+        }
+
+    }
+
+    g_free(sn_tab);
+}
+
+static void dump_json_image_info(ImageInfo *info)
+{
+    Error *errp = NULL;
+    QString *str;
+    QmpOutputVisitor *ov = qmp_output_visitor_new();
+    QObject *obj;
+    visit_type_ImageInfo(qmp_output_get_visitor(ov),
+                         &info, NULL, &errp);
+    obj = qmp_output_get_qobject(ov);
+    str = qobject_to_json_pretty(obj);
+    assert(str != NULL);
+    printf("%s\n", qstring_get_str(str));
+    qobject_decref(obj);
+    qmp_output_visitor_cleanup(ov);
+    QDECREF(str);
+}
+
+static void collect_image_info(BlockDriverState *bs,
+                   ImageInfo *info,
+                   const char *filename,
+                   const char *fmt)
 {
-    int c;
-    const char *filename, *fmt;
-    BlockDriverState *bs;
-    char size_buf[128], dsize_buf[128];
     uint64_t total_sectors;
-    int64_t allocated_size;
     char backing_filename[1024];
     char backing_filename2[1024];
     BlockDriverInfo bdi;
 
+    bdrv_get_geometry(bs, &total_sectors);
+
+    info->filename        = g_strdup(filename);
+    info->format          = g_strdup(bdrv_get_format_name(bs));
+    info->virtual_size    = total_sectors * 512;
+    info->actual_size     = bdrv_get_allocated_file_size(bs);
+    info->has_actual_size = info->actual_size >= 0;
+    if (bdrv_is_encrypted(bs)) {
+        info->encrypted = true;
+        info->has_encrypted = true;
+    }
+    if (bdrv_get_info(bs, &bdi) >= 0) {
+        if (bdi.cluster_size != 0) {
+            info->cluster_size = bdi.cluster_size;
+            info->has_cluster_size = true;
+        }
+        info->dirty_flag = bdi.is_dirty;
+        info->has_dirty_flag = true;
+    }
+    bdrv_get_backing_filename(bs, backing_filename, sizeof(backing_filename));
+    if (backing_filename[0] != '\0') {
+        info->backing_filename = g_strdup(backing_filename);
+        info->has_backing_filename = true;
+        bdrv_get_full_backing_filename(bs, backing_filename2,
+                                       sizeof(backing_filename2));
+
+        if (strcmp(backing_filename, backing_filename2) != 0) {
+            info->full_backing_filename =
+                        g_strdup(backing_filename2);
+            info->has_full_backing_filename = true;
+        }
+
+        if (bs->backing_format[0]) {
+            info->backing_filename_format = g_strdup(bs->backing_format);
+            info->has_backing_filename_format = true;
+        }
+    }
+}
+
+static void dump_human_image_info(ImageInfo *info)
+{
+    char size_buf[128], dsize_buf[128];
+    if (!info->has_actual_size) {
+        snprintf(dsize_buf, sizeof(dsize_buf), "unavailable");
+    } else {
+        get_human_readable_size(dsize_buf, sizeof(dsize_buf),
+                                info->actual_size);
+    }
+    get_human_readable_size(size_buf, sizeof(size_buf), info->virtual_size);
+    printf("image: %s\n"
+           "file format: %s\n"
+           "virtual size: %s (%" PRId64 " bytes)\n"
+           "disk size: %s\n",
+           info->filename, info->format, size_buf,
+           info->virtual_size,
+           dsize_buf);
+
+    if (info->has_encrypted && info->encrypted) {
+        printf("encrypted: yes\n");
+    }
+
+    if (info->has_cluster_size) {
+        printf("cluster_size: %" PRId64 "\n", info->cluster_size);
+    }
+
+    if (info->has_dirty_flag && info->dirty_flag) {
+        printf("cleanly shut down: no\n");
+    }
+
+    if (info->has_backing_filename) {
+        printf("backing file: %s", info->backing_filename);
+        if (info->has_full_backing_filename) {
+            printf(" (actual path: %s)", info->full_backing_filename);
+        }
+        putchar('\n');
+        if (info->has_backing_filename_format) {
+            printf("backing file format: %s\n", info->backing_filename_format);
+        }
+    }
+}
+
+enum {OPTION_OUTPUT = 256};
+
+typedef enum OutputFormat {
+    OFORMAT_JSON,
+    OFORMAT_HUMAN,
+} OutputFormat;
+
+static int img_info(int argc, char **argv)
+{
+    int c;
+    OutputFormat output_format = OFORMAT_HUMAN;
+    const char *filename, *fmt, *output;
+    BlockDriverState *bs;
+    ImageInfo *info;
+
     fmt = NULL;
+    output = NULL;
     for(;;) {
-        c = getopt(argc, argv, "f:h");
+        int option_index = 0;
+        static const struct option long_options[] = {
+            {"help", no_argument, 0, 'h'},
+            {"format", required_argument, 0, 'f'},
+            {"output", required_argument, 0, OPTION_OUTPUT},
+            {0, 0, 0, 0}
+        };
+        c = getopt_long(argc, argv, "f:h",
+                        long_options, &option_index);
         if (c == -1) {
             break;
         }
@@ -1128,6 +1287,9 @@ static int img_info(int argc, char **argv)
         case 'f':
             fmt = optarg;
             break;
+        case OPTION_OUTPUT:
+            output = optarg;
+            break;
         }
     }
     if (optind >= argc) {
@@ -1135,48 +1297,35 @@ static int img_info(int argc, char **argv)
     }
     filename = argv[optind++];
 
-    bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS | BDRV_O_NO_BACKING);
-    if (!bs) {
+    if (output && !strcmp(output, "json")) {
+        output_format = OFORMAT_JSON;
+    } else if (output && !strcmp(output, "human")) {
+        output_format = OFORMAT_HUMAN;
+    } else if (output) {
+        error_report("--output must be used with human or json as argument.");
         return 1;
     }
-    bdrv_get_geometry(bs, &total_sectors);
-    get_human_readable_size(size_buf, sizeof(size_buf), total_sectors * 512);
-    allocated_size = bdrv_get_allocated_file_size(bs);
-    if (allocated_size < 0) {
-        snprintf(dsize_buf, sizeof(dsize_buf), "unavailable");
-    } else {
-        get_human_readable_size(dsize_buf, sizeof(dsize_buf),
-                                allocated_size);
-    }
-    printf("image: %s\n"
-           "file format: %s\n"
-           "virtual size: %s (%" PRId64 " bytes)\n"
-           "disk size: %s\n",
-           filename, bdrv_get_format_name(bs), size_buf,
-           (total_sectors * 512),
-           dsize_buf);
-    if (bdrv_is_encrypted(bs)) {
-        printf("encrypted: yes\n");
-    }
-    if (bdrv_get_info(bs, &bdi) >= 0) {
-        if (bdi.cluster_size != 0) {
-            printf("cluster_size: %d\n", bdi.cluster_size);
-        }
-        if (bdi.is_dirty) {
-            printf("cleanly shut down: no\n");
-        }
+
+    bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS | BDRV_O_NO_BACKING, false);
+    if (!bs) {
+        return 1;
     }
-    bdrv_get_backing_filename(bs, backing_filename, sizeof(backing_filename));
-    if (backing_filename[0] != '\0') {
-        bdrv_get_full_backing_filename(bs, backing_filename2,
-                                       sizeof(backing_filename2));
-        printf("backing file: %s", backing_filename);
-        if (strcmp(backing_filename, backing_filename2) != 0) {
-            printf(" (actual path: %s)", backing_filename2);
-        }
-        putchar('\n');
+
+    info = g_new0(ImageInfo, 1);
+    collect_image_info(bs, info, filename, fmt);
+
+    switch (output_format) {
+    case OFORMAT_HUMAN:
+        dump_human_image_info(info);
+        dump_snapshots(bs);
+        break;
+    case OFORMAT_JSON:
+        collect_snapshots(bs, info);
+        dump_json_image_info(info);
+        break;
     }
-    dump_snapshots(bs);
+
+    qapi_free_ImageInfo(info);
     bdrv_delete(bs);
     return 0;
 }
@@ -1248,7 +1397,7 @@ static int img_snapshot(int argc, char **argv)
     filename = argv[optind++];
 
     /* Open the image */
-    bs = bdrv_new_open(filename, NULL, bdrv_oflags);
+    bs = bdrv_new_open(filename, NULL, bdrv_oflags, true);
     if (!bs) {
         return 1;
     }
@@ -1366,7 +1515,7 @@ static int img_rebase(int argc, char **argv)
      * Ignore the old backing file for unsafe rebase in case we want to correct
      * the reference to a renamed or moved backing file.
      */
-    bs = bdrv_new_open(filename, fmt, flags);
+    bs = bdrv_new_open(filename, fmt, flags, true);
     if (!bs) {
         return 1;
     }
@@ -1639,7 +1788,7 @@ static int img_resize(int argc, char **argv)
     n = qemu_opt_get_size(param, BLOCK_OPT_SIZE, 0);
     qemu_opts_del(param);
 
-    bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS | BDRV_O_RDWR);
+    bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS | BDRV_O_RDWR, true);
     if (!bs) {
         ret = -1;
         goto out;

qemu-img.texi

@@ -129,12 +129,13 @@ created as a copy on write image of the specified base image; the
 @var{backing_file} should have the same content as the input's base image,
 however the path, image format, etc may differ.
 
-@item info [-f @var{fmt}] @var{filename}
+@item info [-f @var{fmt}] [--output=@var{ofmt}] @var{filename}
 
 Give information about the disk image @var{filename}. Use it in
 particular to know the size reserved on disk which can be different
 from the displayed size. If VM snapshots are stored in the disk image,
-they are displayed too.
+they are displayed too. The command can output in the format @var{ofmt}
+which is either @code{human} or @code{json}.
 
 @item snapshot [-l | -a @var{snapshot} | -c @var{snapshot} | -d @var{snapshot} ] @var{filename}