]> git.proxmox.com Git - mirror_qemu.git/blobdiff - qemu-img.c
intel-iommu: trace domain id during page walk
[mirror_qemu.git] / qemu-img.c
index b506839ef083aaaa2c01820f9cdb8ad9e57881d4..86060aab7189bd7075dc24938d28bc168aea4e10 100644 (file)
@@ -22,6 +22,8 @@
  * THE SOFTWARE.
  */
 #include "qemu/osdep.h"
+#include <getopt.h>
+
 #include "qemu-version.h"
 #include "qapi/error.h"
 #include "qapi-visit.h"
@@ -42,7 +44,6 @@
 #include "block/qapi.h"
 #include "crypto/init.h"
 #include "trace/control.h"
-#include <getopt.h>
 
 #define QEMU_IMG_VERSION "qemu-img version " QEMU_VERSION QEMU_PKGVERSION \
                           "\n" QEMU_COPYRIGHT "\n"
@@ -60,6 +61,10 @@ enum {
     OPTION_PATTERN = 260,
     OPTION_FLUSH_INTERVAL = 261,
     OPTION_NO_DRAIN = 262,
+    OPTION_TARGET_IMAGE_OPTS = 263,
+    OPTION_SIZE = 264,
+    OPTION_PREALLOCATION = 265,
+    OPTION_SHRINK = 266,
 };
 
 typedef enum OutputFormat {
@@ -146,9 +151,11 @@ static void QEMU_NORETURN help(void)
            "  'snapshot_id_or_name' is deprecated, use 'snapshot_param'\n"
            "    instead\n"
            "  '-c' indicates that target image must be compressed (qcow format only)\n"
-           "  '-u' enables unsafe rebasing. It is assumed that old and new backing file\n"
-           "       match exactly. The image doesn't need a working backing file before\n"
-           "       rebasing in this case (useful for renaming the backing file)\n"
+           "  '-u' allows unsafe backing chains. For rebasing, it is assumed that old and\n"
+           "       new backing file match exactly. The image doesn't need a working\n"
+           "       backing file before rebasing in this case (useful for renaming the\n"
+           "       backing file). For image creation, allow creating without attempting\n"
+           "       to open the backing file.\n"
            "  '-h' with or without a command shows this help and lists the supported formats\n"
            "  '-p' show progress of command (only certain commands)\n"
            "  '-q' use Quiet mode - do not print any output (except errors)\n"
@@ -194,7 +201,7 @@ static void QEMU_NORETURN help(void)
 
     printf("%s\nSupported formats:", help_msg);
     bdrv_iterate_format(format_print, NULL);
-    printf("\n");
+    printf("\n\n" QEMU_HELP_BOTTOM "\n");
     exit(EXIT_SUCCESS);
 }
 
@@ -259,29 +266,6 @@ static int print_block_option_help(const char *filename, const char *fmt)
 }
 
 
-static int img_open_password(BlockBackend *blk, const char *filename,
-                             int flags, bool quiet)
-{
-    BlockDriverState *bs;
-    char password[256];
-
-    bs = blk_bs(blk);
-    if (bdrv_is_encrypted(bs) && bdrv_key_required(bs) &&
-        !(flags & BDRV_O_NO_IO)) {
-        qprintf(quiet, "Disk image '%s' is encrypted.\n", filename);
-        if (qemu_read_password(password, sizeof(password)) < 0) {
-            error_report("No password given");
-            return -1;
-        }
-        if (bdrv_set_key(bs, password) < 0) {
-            error_report("invalid password");
-            return -1;
-        }
-    }
-    return 0;
-}
-
-
 static BlockBackend *img_open_opts(const char *optstr,
                                    QemuOpts *opts, int flags, bool writethrough,
                                    bool quiet, bool force_share)
@@ -292,11 +276,12 @@ static BlockBackend *img_open_opts(const char *optstr,
     options = qemu_opts_to_qdict(opts, NULL);
     if (force_share) {
         if (qdict_haskey(options, BDRV_OPT_FORCE_SHARE)
-            && !qdict_get_bool(options, BDRV_OPT_FORCE_SHARE)) {
+            && strcmp(qdict_get_str(options, BDRV_OPT_FORCE_SHARE), "on")) {
             error_report("--force-share/-U conflicts with image options");
+            QDECREF(options);
             return NULL;
         }
-        qdict_put(options, BDRV_OPT_FORCE_SHARE, qbool_from_bool(true));
+        qdict_put_str(options, BDRV_OPT_FORCE_SHARE, "on");
     }
     blk = blk_new_open(NULL, NULL, options, flags, &local_err);
     if (!blk) {
@@ -305,28 +290,27 @@ static BlockBackend *img_open_opts(const char *optstr,
     }
     blk_set_enable_write_cache(blk, !writethrough);
 
-    if (img_open_password(blk, optstr, flags, quiet) < 0) {
-        blk_unref(blk);
-        return NULL;
-    }
     return blk;
 }
 
 static BlockBackend *img_open_file(const char *filename,
+                                   QDict *options,
                                    const char *fmt, int flags,
                                    bool writethrough, bool quiet,
                                    bool force_share)
 {
     BlockBackend *blk;
     Error *local_err = NULL;
-    QDict *options = qdict_new();
 
+    if (!options) {
+        options = qdict_new();
+    }
     if (fmt) {
         qdict_put_str(options, "driver", fmt);
     }
 
     if (force_share) {
-        qdict_put(options, BDRV_OPT_FORCE_SHARE, qbool_from_bool(true));
+        qdict_put_bool(options, BDRV_OPT_FORCE_SHARE, true);
     }
     blk = blk_new_open(filename, NULL, options, flags, &local_err);
     if (!blk) {
@@ -335,14 +319,39 @@ static BlockBackend *img_open_file(const char *filename,
     }
     blk_set_enable_write_cache(blk, !writethrough);
 
-    if (img_open_password(blk, filename, flags, quiet) < 0) {
-        blk_unref(blk);
-        return NULL;
-    }
     return blk;
 }
 
 
+static int img_add_key_secrets(void *opaque,
+                               const char *name, const char *value,
+                               Error **errp)
+{
+    QDict *options = opaque;
+
+    if (g_str_has_suffix(name, "key-secret")) {
+        qdict_put_str(options, name, value);
+    }
+
+    return 0;
+}
+
+static BlockBackend *img_open_new_file(const char *filename,
+                                       QemuOpts *create_opts,
+                                       const char *fmt, int flags,
+                                       bool writethrough, bool quiet,
+                                       bool force_share)
+{
+    QDict *options = NULL;
+
+    options = qdict_new();
+    qemu_opt_foreach(create_opts, img_add_key_secrets, options, &error_abort);
+
+    return img_open_file(filename, options, fmt, flags, writethrough, quiet,
+                         force_share);
+}
+
+
 static BlockBackend *img_open(bool image_opts,
                               const char *filename,
                               const char *fmt, int flags, bool writethrough,
@@ -363,7 +372,7 @@ static BlockBackend *img_open(bool image_opts,
         blk = img_open_opts(filename, opts, flags, writethrough, quiet,
                             force_share);
     } else {
-        blk = img_open_file(filename, fmt, flags, writethrough, quiet,
+        blk = img_open_file(filename, NULL, fmt, flags, writethrough, quiet,
                             force_share);
     }
     return blk;
@@ -423,6 +432,7 @@ static int img_create(int argc, char **argv)
     char *options = NULL;
     Error *local_err = NULL;
     bool quiet = false;
+    int flags = 0;
 
     for(;;) {
         static const struct option long_options[] = {
@@ -430,7 +440,7 @@ static int img_create(int argc, char **argv)
             {"object", required_argument, 0, OPTION_OBJECT},
             {0, 0, 0, 0}
         };
-        c = getopt_long(argc, argv, ":F:b:f:he6o:q",
+        c = getopt_long(argc, argv, ":F:b:f:ho:qu",
                         long_options, NULL);
         if (c == -1) {
             break;
@@ -454,14 +464,6 @@ static int img_create(int argc, char **argv)
         case 'f':
             fmt = optarg;
             break;
-        case 'e':
-            error_report("option -e is deprecated, please use \'-o "
-                  "encryption\' instead!");
-            goto fail;
-        case '6':
-            error_report("option -6 is deprecated, please use \'-o "
-                  "compat6\' instead!");
-            goto fail;
         case 'o':
             if (!is_valid_option_list(optarg)) {
                 error_report("Invalid option list: %s", optarg);
@@ -478,6 +480,9 @@ static int img_create(int argc, char **argv)
         case 'q':
             quiet = true;
             break;
+        case 'u':
+            flags |= BDRV_O_NO_BACKING;
+            break;
         case OPTION_OBJECT: {
             QemuOpts *opts;
             opts = qemu_opts_parse_noisily(&qemu_object_opts,
@@ -530,7 +535,7 @@ static int img_create(int argc, char **argv)
     }
 
     bdrv_img_create(filename, fmt, base_filename, base_fmt,
-                    options, img_size, 0, quiet, &local_err);
+                    options, img_size, flags, quiet, &local_err);
     if (local_err) {
         error_reportf_err(local_err, "%s: ", filename);
         goto fail;
@@ -853,22 +858,28 @@ static void common_block_job_cb(void *opaque, int ret)
 static void run_block_job(BlockJob *job, Error **errp)
 {
     AioContext *aio_context = blk_get_aio_context(job->blk);
+    int ret = 0;
 
-    /* FIXME In error cases, the job simply goes away and we access a dangling
-     * pointer below. */
     aio_context_acquire(aio_context);
+    block_job_ref(job);
     do {
         aio_poll(aio_context, true);
         qemu_progress_print(job->len ?
                             ((float)job->offset / job->len * 100.f) : 0.0f, 0);
-    } while (!job->ready);
+    } while (!job->ready && !job->completed);
 
-    block_job_complete_sync(job, errp);
+    if (!job->completed) {
+        ret = block_job_complete_sync(job, errp);
+    } else {
+        ret = job->ret;
+    }
+    block_job_unref(job);
     aio_context_release(aio_context);
 
-    /* A block job may finish instantaneously without publishing any progress,
-     * so just signal completion here */
-    qemu_progress_print(100.f, 0);
+    /* publish completion progress only when success */
+    if (!ret) {
+        qemu_progress_print(100.f, 0);
+    }
 }
 
 static int img_commit(int argc, char **argv)
@@ -1053,6 +1064,28 @@ done:
     return 0;
 }
 
+/*
+ * Returns -1 if 'buf' contains only zeroes, otherwise the byte index
+ * of the first sector boundary within buf where the sector contains a
+ * non-zero byte.  This function is robust to a buffer that is not
+ * sector-aligned.
+ */
+static int64_t find_nonzero(const uint8_t *buf, int64_t n)
+{
+    int64_t i;
+    int64_t end = QEMU_ALIGN_DOWN(n, BDRV_SECTOR_SIZE);
+
+    for (i = 0; i < end; i += BDRV_SECTOR_SIZE) {
+        if (!buffer_is_zero(buf + i, BDRV_SECTOR_SIZE)) {
+            return i;
+        }
+    }
+    if (i < n && !buffer_is_zero(buf + i, n - end)) {
+        return i;
+    }
+    return -1;
+}
+
 /*
  * Returns true iff the first sector pointed to by 'buf' contains at least
  * a non-NUL byte.
@@ -1123,31 +1156,28 @@ static int is_allocated_sectors_min(const uint8_t *buf, int n, int *pnum,
 }
 
 /*
- * Compares two buffers sector by sector. Returns 0 if the first sector of both
- * buffers matches, non-zero otherwise.
+ * Compares two buffers sector by sector. Returns 0 if the first
+ * sector of each buffer matches, non-zero otherwise.
  *
- * pnum is set to the number of sectors (including and immediately following
- * the first one) that are known to have the same comparison result
+ * pnum is set to the sector-aligned size of the buffer prefix that
+ * has the same matching status as the first sector.
  */
-static int compare_sectors(const uint8_t *buf1, const uint8_t *buf2, int n,
-    int *pnum)
+static int compare_buffers(const uint8_t *buf1, const uint8_t *buf2,
+                           int64_t bytes, int64_t *pnum)
 {
     bool res;
-    int i;
+    int64_t i = MIN(bytes, BDRV_SECTOR_SIZE);
 
-    if (n <= 0) {
-        *pnum = 0;
-        return 0;
-    }
+    assert(bytes > 0);
 
-    res = !!memcmp(buf1, buf2, 512);
-    for(i = 1; i < n; i++) {
-        buf1 += 512;
-        buf2 += 512;
+    res = !!memcmp(buf1, buf2, i);
+    while (i < bytes) {
+        int64_t len = MIN(bytes - i, BDRV_SECTOR_SIZE);
 
-        if (!!memcmp(buf1, buf2, 512) != res) {
+        if (!!memcmp(buf1 + i, buf2 + i, len) != res) {
             break;
         }
+        i += len;
     }
 
     *pnum = i;
@@ -1156,45 +1186,38 @@ static int compare_sectors(const uint8_t *buf1, const uint8_t *buf2, int n,
 
 #define IO_BUF_SIZE (2 * 1024 * 1024)
 
-static int64_t sectors_to_bytes(int64_t sectors)
-{
-    return sectors << BDRV_SECTOR_BITS;
-}
-
-static int64_t sectors_to_process(int64_t total, int64_t from)
-{
-    return MIN(total - from, IO_BUF_SIZE >> BDRV_SECTOR_BITS);
-}
-
 /*
  * Check if passed sectors are empty (not allocated or contain only 0 bytes)
  *
- * Returns 0 in case sectors are filled with 0, 1 if sectors contain non-zero
- * data and negative value on error.
+ * Intended for use by 'qemu-img compare': Returns 0 in case sectors are
+ * filled with 0, 1 if sectors contain non-zero data (this is a comparison
+ * failure), and 4 on error (the exit status for read errors), after emitting
+ * an error message.
  *
  * @param blk:  BlockBackend for the image
- * @param sect_num: Number of first sector to check
- * @param sect_count: Number of sectors to check
+ * @param offset: Starting offset to check
+ * @param bytes: Number of bytes to check
  * @param filename: Name of disk file we are checking (logging purpose)
  * @param buffer: Allocated buffer for storing read data
  * @param quiet: Flag for quiet mode
  */
-static int check_empty_sectors(BlockBackend *blk, int64_t sect_num,
-                               int sect_count, const char *filename,
+static int check_empty_sectors(BlockBackend *blk, int64_t offset,
+                               int64_t bytes, const char *filename,
                                uint8_t *buffer, bool quiet)
 {
-    int pnum, ret = 0;
-    ret = blk_pread(blk, sect_num << BDRV_SECTOR_BITS, buffer,
-                    sect_count << BDRV_SECTOR_BITS);
+    int ret = 0;
+    int64_t idx;
+
+    ret = blk_pread(blk, offset, buffer, bytes);
     if (ret < 0) {
         error_report("Error while reading offset %" PRId64 " of %s: %s",
-                     sectors_to_bytes(sect_num), filename, strerror(-ret));
-        return ret;
+                     offset, filename, strerror(-ret));
+        return 4;
     }
-    ret = is_allocated_sectors(buffer, sect_count, &pnum);
-    if (ret || pnum != sect_count) {
+    idx = find_nonzero(buffer, bytes);
+    if (idx >= 0) {
         qprintf(quiet, "Content mismatch at offset %" PRId64 "!\n",
-                sectors_to_bytes(ret ? sect_num : sect_num + pnum));
+                offset + idx);
         return 1;
     }
 
@@ -1213,18 +1236,18 @@ static int img_compare(int argc, char **argv)
     const char *fmt1 = NULL, *fmt2 = NULL, *cache, *filename1, *filename2;
     BlockBackend *blk1, *blk2;
     BlockDriverState *bs1, *bs2;
-    int64_t total_sectors1, total_sectors2;
+    int64_t total_size1, total_size2;
     uint8_t *buf1 = NULL, *buf2 = NULL;
-    int pnum1, pnum2;
+    int64_t pnum1, pnum2;
     int allocated1, allocated2;
     int ret = 0; /* return value - 0 Ident, 1 Different, >1 Error */
     bool progress = false, quiet = false, strict = false;
     int flags;
     bool writethrough;
-    int64_t total_sectors;
-    int64_t sector_num = 0;
-    int64_t nb_sectors;
-    int c, pnum;
+    int64_t total_size;
+    int64_t offset = 0;
+    int64_t chunk;
+    int c;
     uint64_t progress_base;
     bool image_opts = false;
     bool force_share = false;
@@ -1337,42 +1360,37 @@ static int img_compare(int argc, char **argv)
 
     buf1 = blk_blockalign(blk1, IO_BUF_SIZE);
     buf2 = blk_blockalign(blk2, IO_BUF_SIZE);
-    total_sectors1 = blk_nb_sectors(blk1);
-    if (total_sectors1 < 0) {
+    total_size1 = blk_getlength(blk1);
+    if (total_size1 < 0) {
         error_report("Can't get size of %s: %s",
-                     filename1, strerror(-total_sectors1));
+                     filename1, strerror(-total_size1));
         ret = 4;
         goto out;
     }
-    total_sectors2 = blk_nb_sectors(blk2);
-    if (total_sectors2 < 0) {
+    total_size2 = blk_getlength(blk2);
+    if (total_size2 < 0) {
         error_report("Can't get size of %s: %s",
-                     filename2, strerror(-total_sectors2));
+                     filename2, strerror(-total_size2));
         ret = 4;
         goto out;
     }
-    total_sectors = MIN(total_sectors1, total_sectors2);
-    progress_base = MAX(total_sectors1, total_sectors2);
+    total_size = MIN(total_size1, total_size2);
+    progress_base = MAX(total_size1, total_size2);
 
     qemu_progress_print(0, 100);
 
-    if (strict && total_sectors1 != total_sectors2) {
+    if (strict && total_size1 != total_size2) {
         ret = 1;
         qprintf(quiet, "Strict mode: Image size mismatch!\n");
         goto out;
     }
 
-    for (;;) {
-        int64_t status1, status2;
-        BlockDriverState *file;
+    while (offset < total_size) {
+        int status1, status2;
 
-        nb_sectors = sectors_to_process(total_sectors, sector_num);
-        if (nb_sectors <= 0) {
-            break;
-        }
-        status1 = bdrv_get_block_status_above(bs1, NULL, sector_num,
-                                              total_sectors1 - sector_num,
-                                              &pnum1, &file);
+        status1 = bdrv_block_status_above(bs1, NULL, offset,
+                                          total_size1 - offset, &pnum1, NULL,
+                                          NULL);
         if (status1 < 0) {
             ret = 3;
             error_report("Sector allocation test failed for %s", filename1);
@@ -1380,108 +1398,92 @@ static int img_compare(int argc, char **argv)
         }
         allocated1 = status1 & BDRV_BLOCK_ALLOCATED;
 
-        status2 = bdrv_get_block_status_above(bs2, NULL, sector_num,
-                                              total_sectors2 - sector_num,
-                                              &pnum2, &file);
+        status2 = bdrv_block_status_above(bs2, NULL, offset,
+                                          total_size2 - offset, &pnum2, NULL,
+                                          NULL);
         if (status2 < 0) {
             ret = 3;
             error_report("Sector allocation test failed for %s", filename2);
             goto out;
         }
         allocated2 = status2 & BDRV_BLOCK_ALLOCATED;
-        if (pnum1) {
-            nb_sectors = MIN(nb_sectors, pnum1);
-        }
-        if (pnum2) {
-            nb_sectors = MIN(nb_sectors, pnum2);
-        }
+
+        assert(pnum1 && pnum2);
+        chunk = MIN(pnum1, pnum2);
 
         if (strict) {
-            if ((status1 & ~BDRV_BLOCK_OFFSET_MASK) !=
-                (status2 & ~BDRV_BLOCK_OFFSET_MASK)) {
+            if (status1 != status2) {
                 ret = 1;
                 qprintf(quiet, "Strict mode: Offset %" PRId64
-                        " block status mismatch!\n",
-                        sectors_to_bytes(sector_num));
+                        " block status mismatch!\n", offset);
                 goto out;
             }
         }
         if ((status1 & BDRV_BLOCK_ZERO) && (status2 & BDRV_BLOCK_ZERO)) {
-            nb_sectors = MIN(pnum1, pnum2);
+            /* nothing to do */
         } else if (allocated1 == allocated2) {
             if (allocated1) {
-                ret = blk_pread(blk1, sector_num << BDRV_SECTOR_BITS, buf1,
-                                nb_sectors << BDRV_SECTOR_BITS);
+                int64_t pnum;
+
+                chunk = MIN(chunk, IO_BUF_SIZE);
+                ret = blk_pread(blk1, offset, buf1, chunk);
                 if (ret < 0) {
-                    error_report("Error while reading offset %" PRId64 " of %s:"
-                                 " %s", sectors_to_bytes(sector_num), filename1,
-                                 strerror(-ret));
+                    error_report("Error while reading offset %" PRId64
+                                 " of %s: %s",
+                                 offset, filename1, strerror(-ret));
                     ret = 4;
                     goto out;
                 }
-                ret = blk_pread(blk2, sector_num << BDRV_SECTOR_BITS, buf2,
-                                nb_sectors << BDRV_SECTOR_BITS);
+                ret = blk_pread(blk2, offset, buf2, chunk);
                 if (ret < 0) {
                     error_report("Error while reading offset %" PRId64
-                                 " of %s: %s", sectors_to_bytes(sector_num),
-                                 filename2, strerror(-ret));
+                                 " of %s: %s",
+                                 offset, filename2, strerror(-ret));
                     ret = 4;
                     goto out;
                 }
-                ret = compare_sectors(buf1, buf2, nb_sectors, &pnum);
-                if (ret || pnum != nb_sectors) {
+                ret = compare_buffers(buf1, buf2, chunk, &pnum);
+                if (ret || pnum != chunk) {
                     qprintf(quiet, "Content mismatch at offset %" PRId64 "!\n",
-                            sectors_to_bytes(
-                                ret ? sector_num : sector_num + pnum));
+                            offset + (ret ? 0 : pnum));
                     ret = 1;
                     goto out;
                 }
             }
         } else {
-
+            chunk = MIN(chunk, IO_BUF_SIZE);
             if (allocated1) {
-                ret = check_empty_sectors(blk1, sector_num, nb_sectors,
+                ret = check_empty_sectors(blk1, offset, chunk,
                                           filename1, buf1, quiet);
             } else {
-                ret = check_empty_sectors(blk2, sector_num, nb_sectors,
+                ret = check_empty_sectors(blk2, offset, chunk,
                                           filename2, buf1, quiet);
             }
             if (ret) {
-                if (ret < 0) {
-                    error_report("Error while reading offset %" PRId64 ": %s",
-                                 sectors_to_bytes(sector_num), strerror(-ret));
-                    ret = 4;
-                }
                 goto out;
             }
         }
-        sector_num += nb_sectors;
-        qemu_progress_print(((float) nb_sectors / progress_base)*100, 100);
+        offset += chunk;
+        qemu_progress_print(((float) chunk / progress_base) * 100, 100);
     }
 
-    if (total_sectors1 != total_sectors2) {
+    if (total_size1 != total_size2) {
         BlockBackend *blk_over;
-        int64_t total_sectors_over;
         const char *filename_over;
 
         qprintf(quiet, "Warning: Image size mismatch!\n");
-        if (total_sectors1 > total_sectors2) {
-            total_sectors_over = total_sectors1;
+        if (total_size1 > total_size2) {
             blk_over = blk1;
             filename_over = filename1;
         } else {
-            total_sectors_over = total_sectors2;
             blk_over = blk2;
             filename_over = filename2;
         }
 
-        for (;;) {
-            nb_sectors = sectors_to_process(total_sectors_over, sector_num);
-            if (nb_sectors <= 0) {
-                break;
-            }
-            ret = bdrv_is_allocated_above(blk_bs(blk_over), NULL, sector_num,
-                                          nb_sectors, &pnum);
+        while (offset < progress_base) {
+            ret = bdrv_block_status_above(blk_bs(blk_over), NULL, offset,
+                                          progress_base - offset, &chunk,
+                                          NULL, NULL);
             if (ret < 0) {
                 ret = 3;
                 error_report("Sector allocation test failed for %s",
@@ -1489,22 +1491,16 @@ static int img_compare(int argc, char **argv)
                 goto out;
 
             }
-            nb_sectors = pnum;
-            if (ret) {
-                ret = check_empty_sectors(blk_over, sector_num, nb_sectors,
+            if (ret & BDRV_BLOCK_ALLOCATED && !(ret & BDRV_BLOCK_ZERO)) {
+                chunk = MIN(chunk, IO_BUF_SIZE);
+                ret = check_empty_sectors(blk_over, offset, chunk,
                                           filename_over, buf1, quiet);
                 if (ret) {
-                    if (ret < 0) {
-                        error_report("Error while reading offset %" PRId64
-                                     " of %s: %s", sectors_to_bytes(sector_num),
-                                     filename_over, strerror(-ret));
-                        ret = 4;
-                    }
                     goto out;
                 }
             }
-            sector_num += nb_sectors;
-            qemu_progress_print(((float) nb_sectors / progress_base)*100, 100);
+            offset += chunk;
+            qemu_progress_print(((float) chunk / progress_base) * 100, 100);
         }
     }
 
@@ -1572,8 +1568,8 @@ static void convert_select_part(ImgConvertState *s, int64_t sector_num,
 
 static int convert_iteration_sectors(ImgConvertState *s, int64_t sector_num)
 {
-    int64_t ret, src_cur_offset;
-    int n, src_cur;
+    int64_t src_cur_offset;
+    int ret, n, src_cur;
 
     convert_select_part(s, sector_num, &src_cur, &src_cur_offset);
 
@@ -1581,19 +1577,24 @@ static int convert_iteration_sectors(ImgConvertState *s, int64_t sector_num)
     n = MIN(s->total_sectors - sector_num, BDRV_REQUEST_MAX_SECTORS);
 
     if (s->sector_next_status <= sector_num) {
-        BlockDriverState *file;
+        int64_t count = n * BDRV_SECTOR_SIZE;
+
         if (s->target_has_backing) {
-            ret = bdrv_get_block_status(blk_bs(s->src[src_cur]),
-                                        sector_num - src_cur_offset,
-                                        n, &n, &file);
+
+            ret = bdrv_block_status(blk_bs(s->src[src_cur]),
+                                    (sector_num - src_cur_offset) *
+                                    BDRV_SECTOR_SIZE,
+                                    count, &count, NULL, NULL);
         } else {
-            ret = bdrv_get_block_status_above(blk_bs(s->src[src_cur]), NULL,
-                                              sector_num - src_cur_offset,
-                                              n, &n, &file);
+            ret = bdrv_block_status_above(blk_bs(s->src[src_cur]), NULL,
+                                          (sector_num - src_cur_offset) *
+                                          BDRV_SECTOR_SIZE,
+                                          count, &count, NULL, NULL);
         }
         if (ret < 0) {
             return ret;
         }
+        n = DIV_ROUND_UP(count, BDRV_SECTOR_SIZE);
 
         if (ret & BDRV_BLOCK_ZERO) {
             s->status = BLK_ZERO;
@@ -1913,10 +1914,10 @@ static int convert_do_copy(ImgConvertState *s)
 static int img_convert(int argc, char **argv)
 {
     int c, bs_i, flags, src_flags = 0;
-    const char *fmt = NULL, *out_fmt = "raw", *cache = "unsafe",
+    const char *fmt = NULL, *out_fmt = NULL, *cache = "unsafe",
                *src_cache = BDRV_DEFAULT_CACHE, *out_baseimg = NULL,
                *out_filename, *out_baseimg_param, *snapshot_name = NULL;
-    BlockDriver *drv, *proto_drv;
+    BlockDriver *drv = NULL, *proto_drv = NULL;
     BlockDriverInfo bdi;
     BlockDriverState *out_bs;
     QemuOpts *opts = NULL, *sn_opts = NULL;
@@ -1924,7 +1925,7 @@ static int img_convert(int argc, char **argv)
     char *options = NULL;
     Error *local_err = NULL;
     bool writethrough, src_writethrough, quiet = false, image_opts = false,
-         skip_create = false, progress = false;
+         skip_create = false, progress = false, tgt_image_opts = false;
     int64_t ret = -EINVAL;
     bool force_share = false;
 
@@ -1942,9 +1943,10 @@ static int img_convert(int argc, char **argv)
             {"object", required_argument, 0, OPTION_OBJECT},
             {"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
             {"force-share", no_argument, 0, 'U'},
+            {"target-image-opts", no_argument, 0, OPTION_TARGET_IMAGE_OPTS},
             {0, 0, 0, 0}
         };
-        c = getopt_long(argc, argv, ":hf:O:B:ce6o:s:l:S:pt:T:qnm:WU",
+        c = getopt_long(argc, argv, ":hf:O:B:co:s:l:S:pt:T:qnm:WU",
                         long_options, NULL);
         if (c == -1) {
             break;
@@ -1971,14 +1973,6 @@ static int img_convert(int argc, char **argv)
         case 'c':
             s.compressed = true;
             break;
-        case 'e':
-            error_report("option -e is deprecated, please use \'-o "
-                  "encryption\' instead!");
-            goto fail_getopt;
-        case '6':
-            error_report("option -6 is deprecated, please use \'-o "
-                  "compat6\' instead!");
-            goto fail_getopt;
         case 'o':
             if (!is_valid_option_list(optarg)) {
                 error_report("Invalid option list: %s", optarg);
@@ -2062,9 +2056,16 @@ static int img_convert(int argc, char **argv)
         case OPTION_IMAGE_OPTS:
             image_opts = true;
             break;
+        case OPTION_TARGET_IMAGE_OPTS:
+            tgt_image_opts = true;
+            break;
         }
     }
 
+    if (!out_fmt && !tgt_image_opts) {
+        out_fmt = "raw";
+    }
+
     if (qemu_opts_foreach(&qemu_object_opts,
                           user_creatable_add_opts_foreach,
                           NULL, NULL)) {
@@ -2076,12 +2077,22 @@ static int img_convert(int argc, char **argv)
         goto fail_getopt;
     }
 
+    if (tgt_image_opts && !skip_create) {
+        error_report("--target-image-opts requires use of -n flag");
+        goto fail_getopt;
+    }
+
     s.src_num = argc - optind - 1;
     out_filename = s.src_num >= 1 ? argv[argc - 1] : NULL;
 
     if (options && has_help_option(options)) {
-        ret = print_block_option_help(out_filename, out_fmt);
-        goto fail_getopt;
+        if (out_fmt) {
+            ret = print_block_option_help(out_filename, out_fmt);
+            goto fail_getopt;
+        } else {
+            error_report("Option help requires a format be specified");
+            goto fail_getopt;
+        }
     }
 
     if (s.src_num < 1) {
@@ -2146,22 +2157,22 @@ static int img_convert(int argc, char **argv)
         goto out;
     }
 
-    /* Find driver and parse its options */
-    drv = bdrv_find_format(out_fmt);
-    if (!drv) {
-        error_report("Unknown file format '%s'", out_fmt);
-        ret = -1;
-        goto out;
-    }
+    if (!skip_create) {
+        /* Find driver and parse its options */
+        drv = bdrv_find_format(out_fmt);
+        if (!drv) {
+            error_report("Unknown file format '%s'", out_fmt);
+            ret = -1;
+            goto out;
+        }
 
-    proto_drv = bdrv_find_protocol(out_filename, true, &local_err);
-    if (!proto_drv) {
-        error_report_err(local_err);
-        ret = -1;
-        goto out;
-    }
+        proto_drv = bdrv_find_protocol(out_filename, true, &local_err);
+        if (!proto_drv) {
+            error_report_err(local_err);
+            ret = -1;
+            goto out;
+        }
 
-    if (!skip_create) {
         if (!drv->create_opts) {
             error_report("Format driver '%s' does not support image creation",
                          drv->format_name);
@@ -2215,16 +2226,18 @@ static int img_convert(int argc, char **argv)
     if (s.compressed) {
         bool encryption =
             qemu_opt_get_bool(opts, BLOCK_OPT_ENCRYPT, false);
+        const char *encryptfmt =
+            qemu_opt_get(opts, BLOCK_OPT_ENCRYPT_FORMAT);
         const char *preallocation =
             qemu_opt_get(opts, BLOCK_OPT_PREALLOC);
 
-        if (!drv->bdrv_co_pwritev_compressed) {
+        if (drv && !drv->bdrv_co_pwritev_compressed) {
             error_report("Compression not supported for this file format");
             ret = -1;
             goto out;
         }
 
-        if (encryption) {
+        if (encryption || encryptfmt) {
             error_report("Compression and encryption not supported at "
                          "the same time");
             ret = -1;
@@ -2258,19 +2271,30 @@ static int img_convert(int argc, char **argv)
         goto out;
     }
 
-    /* XXX we should allow --image-opts to trigger use of
-     * img_open() here, but then we have trouble with
-     * the bdrv_create() call which takes different params.
-     * Not critical right now, so fix can wait...
-     */
-    s.target = img_open_file(out_filename, out_fmt, flags, writethrough, quiet,
-                             false);
+    if (skip_create) {
+        s.target = img_open(tgt_image_opts, out_filename, out_fmt,
+                            flags, writethrough, quiet, false);
+    } else {
+        /* TODO ultimately we should allow --target-image-opts
+         * to be used even when -n is not given.
+         * That has to wait for bdrv_create to be improved
+         * to allow filenames in option syntax
+         */
+        s.target = img_open_new_file(out_filename, opts, out_fmt,
+                                     flags, writethrough, quiet, false);
+    }
     if (!s.target) {
         ret = -1;
         goto out;
     }
     out_bs = blk_bs(s.target);
 
+    if (s.compressed && !out_bs->drv->bdrv_co_pwritev_compressed) {
+        error_report("Compression not supported for this file format");
+        ret = -1;
+        goto out;
+    }
+
     /* increase bufsectors from the default 4096 (2M) if opt_transfer
      * or discard_alignment of the out_bs is greater. Limit to 32768 (16MB)
      * as maximum. */
@@ -2632,13 +2656,14 @@ static void dump_map_entry(OutputFormat output_format, MapEntry *e,
     }
 }
 
-static int get_block_status(BlockDriverState *bs, int64_t sector_num,
-                            int nb_sectors, MapEntry *e)
+static int get_block_status(BlockDriverState *bs, int64_t offset,
+                            int64_t bytes, MapEntry *e)
 {
-    int64_t ret;
+    int ret;
     int depth;
     BlockDriverState *file;
     bool has_offset;
+    int64_t map;
 
     /* As an optimization, we could cache the current range of unallocated
      * clusters in each file of the chain, and avoid querying the same
@@ -2647,12 +2672,11 @@ static int get_block_status(BlockDriverState *bs, int64_t sector_num,
 
     depth = 0;
     for (;;) {
-        ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &nb_sectors,
-                                    &file);
+        ret = bdrv_block_status(bs, offset, bytes, &bytes, &map, &file);
         if (ret < 0) {
             return ret;
         }
-        assert(nb_sectors);
+        assert(bytes);
         if (ret & (BDRV_BLOCK_ZERO|BDRV_BLOCK_DATA)) {
             break;
         }
@@ -2668,11 +2692,11 @@ static int get_block_status(BlockDriverState *bs, int64_t sector_num,
     has_offset = !!(ret & BDRV_BLOCK_OFFSET_VALID);
 
     *e = (MapEntry) {
-        .start = sector_num * BDRV_SECTOR_SIZE,
-        .length = nb_sectors * BDRV_SECTOR_SIZE,
+        .start = offset,
+        .length = bytes,
         .data = !!(ret & BDRV_BLOCK_DATA),
         .zero = !!(ret & BDRV_BLOCK_ZERO),
-        .offset = ret & BDRV_BLOCK_OFFSET_MASK,
+        .offset = map,
         .has_offset = has_offset,
         .depth = depth,
         .has_filename = file && has_offset,
@@ -2798,16 +2822,12 @@ static int img_map(int argc, char **argv)
 
     length = blk_getlength(blk);
     while (curr.start + curr.length < length) {
-        int64_t nsectors_left;
-        int64_t sector_num;
-        int n;
-
-        sector_num = (curr.start + curr.length) >> BDRV_SECTOR_BITS;
+        int64_t offset = curr.start + curr.length;
+        int64_t n;
 
         /* Probe up to 1 GiB at a time.  */
-        nsectors_left = DIV_ROUND_UP(length, BDRV_SECTOR_SIZE) - sector_num;
-        n = MIN(1 << (30 - BDRV_SECTOR_BITS), nsectors_left);
-        ret = get_block_status(bs, sector_num, n, &next);
+        n = QEMU_ALIGN_DOWN(MIN(1 << 30, length - offset), BDRV_SECTOR_SIZE);
+        ret = get_block_status(bs, offset, n, &next);
 
         if (ret < 0) {
             error_report("Could not read file metadata: %s", strerror(-ret));
@@ -2969,10 +2989,10 @@ static int img_snapshot(int argc, char **argv)
         break;
 
     case SNAPSHOT_APPLY:
-        ret = bdrv_snapshot_goto(bs, snapshot_name);
+        ret = bdrv_snapshot_goto(bs, snapshot_name, &err);
         if (ret) {
-            error_report("Could not apply snapshot '%s': %d (%s)",
-                snapshot_name, ret, strerror(-ret));
+            error_reportf_err(err, "Could not apply snapshot '%s': ",
+                              snapshot_name);
         }
         break;
 
@@ -3156,8 +3176,7 @@ static int img_rebase(int argc, char **argv)
             if (!options) {
                 options = qdict_new();
             }
-            qdict_put(options, BDRV_OPT_FORCE_SHARE,
-                      qbool_from_bool(true));
+            qdict_put_bool(options, BDRV_OPT_FORCE_SHARE, true);
         }
         bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name));
         blk_old_backing = blk_new_open(backing_name, NULL,
@@ -3171,6 +3190,9 @@ static int img_rebase(int argc, char **argv)
         }
 
         if (out_baseimg[0]) {
+            const char *overlay_filename;
+            char *out_real_path;
+
             options = qdict_new();
             if (out_basefmt) {
                 qdict_put_str(options, "driver", out_basefmt);
@@ -3179,8 +3201,26 @@ static int img_rebase(int argc, char **argv)
                 qdict_put_bool(options, BDRV_OPT_FORCE_SHARE, true);
             }
 
-            blk_new_backing = blk_new_open(out_baseimg, NULL,
+            overlay_filename = bs->exact_filename[0] ? bs->exact_filename
+                                                     : bs->filename;
+            out_real_path = g_malloc(PATH_MAX);
+
+            bdrv_get_full_backing_filename_from_filename(overlay_filename,
+                                                         out_baseimg,
+                                                         out_real_path,
+                                                         PATH_MAX,
+                                                         &local_err);
+            if (local_err) {
+                error_reportf_err(local_err,
+                                  "Could not resolve backing filename: ");
+                ret = -1;
+                g_free(out_real_path);
+                goto out;
+            }
+
+            blk_new_backing = blk_new_open(out_real_path, NULL,
                                            options, src_flags, &local_err);
+            g_free(out_real_path);
             if (!blk_new_backing) {
                 error_reportf_err(local_err,
                                   "Could not open new backing file '%s': ",
@@ -3201,59 +3241,53 @@ static int img_rebase(int argc, char **argv)
      * the image is the same as the original one at any time.
      */
     if (!unsafe) {
-        int64_t num_sectors;
-        int64_t old_backing_num_sectors;
-        int64_t new_backing_num_sectors = 0;
-        uint64_t sector;
-        int n;
+        int64_t size;
+        int64_t old_backing_size;
+        int64_t new_backing_size = 0;
+        uint64_t offset;
+        int64_t n;
         float local_progress = 0;
 
         buf_old = blk_blockalign(blk, IO_BUF_SIZE);
         buf_new = blk_blockalign(blk, IO_BUF_SIZE);
 
-        num_sectors = blk_nb_sectors(blk);
-        if (num_sectors < 0) {
+        size = blk_getlength(blk);
+        if (size < 0) {
             error_report("Could not get size of '%s': %s",
-                         filename, strerror(-num_sectors));
+                         filename, strerror(-size));
             ret = -1;
             goto out;
         }
-        old_backing_num_sectors = blk_nb_sectors(blk_old_backing);
-        if (old_backing_num_sectors < 0) {
+        old_backing_size = blk_getlength(blk_old_backing);
+        if (old_backing_size < 0) {
             char backing_name[PATH_MAX];
 
             bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name));
             error_report("Could not get size of '%s': %s",
-                         backing_name, strerror(-old_backing_num_sectors));
+                         backing_name, strerror(-old_backing_size));
             ret = -1;
             goto out;
         }
         if (blk_new_backing) {
-            new_backing_num_sectors = blk_nb_sectors(blk_new_backing);
-            if (new_backing_num_sectors < 0) {
+            new_backing_size = blk_getlength(blk_new_backing);
+            if (new_backing_size < 0) {
                 error_report("Could not get size of '%s': %s",
-                             out_baseimg, strerror(-new_backing_num_sectors));
+                             out_baseimg, strerror(-new_backing_size));
                 ret = -1;
                 goto out;
             }
         }
 
-        if (num_sectors != 0) {
-            local_progress = (float)100 /
-                (num_sectors / MIN(num_sectors, IO_BUF_SIZE / 512));
+        if (size != 0) {
+            local_progress = (float)100 / (size / MIN(size, IO_BUF_SIZE));
         }
 
-        for (sector = 0; sector < num_sectors; sector += n) {
-
-            /* How many sectors can we handle with the next read? */
-            if (sector + (IO_BUF_SIZE / 512) <= num_sectors) {
-                n = (IO_BUF_SIZE / 512);
-            } else {
-                n = num_sectors - sector;
-            }
+        for (offset = 0; offset < size; offset += n) {
+            /* How many bytes can we handle with the next read? */
+            n = MIN(IO_BUF_SIZE, size - offset);
 
             /* If the cluster is allocated, we don't need to take action */
-            ret = bdrv_is_allocated(bs, sector, n, &n);
+            ret = bdrv_is_allocated(bs, offset, n, &n);
             if (ret < 0) {
                 error_report("error while reading image metadata: %s",
                              strerror(-ret));
@@ -3267,30 +3301,28 @@ static int img_rebase(int argc, char **argv)
              * Read old and new backing file and take into consideration that
              * backing files may be smaller than the COW image.
              */
-            if (sector >= old_backing_num_sectors) {
-                memset(buf_old, 0, n * BDRV_SECTOR_SIZE);
+            if (offset >= old_backing_size) {
+                memset(buf_old, 0, n);
             } else {
-                if (sector + n > old_backing_num_sectors) {
-                    n = old_backing_num_sectors - sector;
+                if (offset + n > old_backing_size) {
+                    n = old_backing_size - offset;
                 }
 
-                ret = blk_pread(blk_old_backing, sector << BDRV_SECTOR_BITS,
-                                buf_old, n << BDRV_SECTOR_BITS);
+                ret = blk_pread(blk_old_backing, offset, buf_old, n);
                 if (ret < 0) {
                     error_report("error while reading from old backing file");
                     goto out;
                 }
             }
 
-            if (sector >= new_backing_num_sectors || !blk_new_backing) {
-                memset(buf_new, 0, n * BDRV_SECTOR_SIZE);
+            if (offset >= new_backing_size || !blk_new_backing) {
+                memset(buf_new, 0, n);
             } else {
-                if (sector + n > new_backing_num_sectors) {
-                    n = new_backing_num_sectors - sector;
+                if (offset + n > new_backing_size) {
+                    n = new_backing_size - offset;
                 }
 
-                ret = blk_pread(blk_new_backing, sector << BDRV_SECTOR_BITS,
-                                buf_new, n << BDRV_SECTOR_BITS);
+                ret = blk_pread(blk_new_backing, offset, buf_new, n);
                 if (ret < 0) {
                     error_report("error while reading from new backing file");
                     goto out;
@@ -3301,15 +3333,13 @@ static int img_rebase(int argc, char **argv)
             uint64_t written = 0;
 
             while (written < n) {
-                int pnum;
+                int64_t pnum;
 
-                if (compare_sectors(buf_old + written * 512,
-                    buf_new + written * 512, n - written, &pnum))
+                if (compare_buffers(buf_old + written, buf_new + written,
+                                    n - written, &pnum))
                 {
-                    ret = blk_pwrite(blk,
-                                     (sector + written) << BDRV_SECTOR_BITS,
-                                     buf_old + written * 512,
-                                     pnum << BDRV_SECTOR_BITS, 0);
+                    ret = blk_pwrite(blk, offset + written,
+                                     buf_old + written, pnum, 0);
                     if (ret < 0) {
                         error_report("Error while writing to COW image: %s",
                             strerror(-ret));
@@ -3371,9 +3401,10 @@ static int img_resize(int argc, char **argv)
     Error *err = NULL;
     int c, ret, relative;
     const char *filename, *fmt, *size;
-    int64_t n, total_size;
+    int64_t n, total_size, current_size;
     bool quiet = false;
     BlockBackend *blk = NULL;
+    PreallocMode prealloc = PREALLOC_MODE_OFF;
     QemuOpts *param;
 
     static QemuOptsList resize_options = {
@@ -3390,6 +3421,7 @@ static int img_resize(int argc, char **argv)
         },
     };
     bool image_opts = false;
+    bool shrink = false;
 
     /* Remove size from argv manually so that negative numbers are not treated
      * as options by getopt. */
@@ -3407,6 +3439,8 @@ static int img_resize(int argc, char **argv)
             {"help", no_argument, 0, 'h'},
             {"object", required_argument, 0, OPTION_OBJECT},
             {"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+            {"preallocation", required_argument, 0, OPTION_PREALLOCATION},
+            {"shrink", no_argument, 0, OPTION_SHRINK},
             {0, 0, 0, 0}
         };
         c = getopt_long(argc, argv, ":f:hq",
@@ -3441,6 +3475,17 @@ static int img_resize(int argc, char **argv)
         case OPTION_IMAGE_OPTS:
             image_opts = true;
             break;
+        case OPTION_PREALLOCATION:
+            prealloc = qapi_enum_parse(&PreallocMode_lookup, optarg,
+                                       PREALLOC_MODE__MAX, NULL);
+            if (prealloc == PREALLOC_MODE__MAX) {
+                error_report("Invalid preallocation mode '%s'", optarg);
+                return 1;
+            }
+            break;
+        case OPTION_SHRINK:
+            shrink = true;
+            break;
         }
     }
     if (optind != argc - 1) {
@@ -3489,8 +3534,16 @@ static int img_resize(int argc, char **argv)
         goto out;
     }
 
+    current_size = blk_getlength(blk);
+    if (current_size < 0) {
+        error_report("Failed to inquire current image length: %s",
+                     strerror(-current_size));
+        ret = -1;
+        goto out;
+    }
+
     if (relative) {
-        total_size = blk_getlength(blk) + n * relative;
+        total_size = current_size + n * relative;
     } else {
         total_size = n;
     }
@@ -3500,7 +3553,30 @@ static int img_resize(int argc, char **argv)
         goto out;
     }
 
-    ret = blk_truncate(blk, total_size, &err);
+    if (total_size <= current_size && prealloc != PREALLOC_MODE_OFF) {
+        error_report("Preallocation can only be used for growing images");
+        ret = -1;
+        goto out;
+    }
+
+    if (total_size < current_size && !shrink) {
+        warn_report("Shrinking an image will delete all data beyond the "
+                    "shrunken image's end. Before performing such an "
+                    "operation, make sure there is no important data there.");
+
+        if (g_strcmp0(bdrv_get_format_name(blk_bs(blk)), "raw") != 0) {
+            error_report(
+              "Use the --shrink option to perform a shrink operation.");
+            ret = -1;
+            goto out;
+        } else {
+            warn_report("Using the --shrink option will suppress this message. "
+                        "Note that future versions of qemu-img may refuse to "
+                        "shrink images without this option.");
+        }
+    }
+
+    ret = blk_truncate(blk, total_size, prealloc, &err);
     if (!ret) {
         qprintf(quiet, "Image resized.\n");
     } else {
@@ -4158,6 +4234,7 @@ static int img_dd(int argc, char **argv)
     };
     const struct option long_options[] = {
         { "help", no_argument, 0, 'h'},
+        { "object", required_argument, 0, OPTION_OBJECT},
         { "image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
         { "force-share", no_argument, 0, 'U'},
         { 0, 0, 0, 0 }
@@ -4186,6 +4263,12 @@ static int img_dd(int argc, char **argv)
         case 'U':
             force_share = true;
             break;
+        case OPTION_OBJECT:
+            if (!qemu_opts_parse_noisily(&qemu_object_opts, optarg, true)) {
+                ret = -1;
+                goto out;
+            }
+            break;
         case OPTION_IMAGE_OPTS:
             image_opts = true;
             break;
@@ -4230,6 +4313,14 @@ static int img_dd(int argc, char **argv)
         ret = -1;
         goto out;
     }
+
+    if (qemu_opts_foreach(&qemu_object_opts,
+                          user_creatable_add_opts_foreach,
+                          NULL, NULL)) {
+        ret = -1;
+        goto out;
+    }
+
     blk1 = img_open(image_opts, in.filename, fmt, 0, false, false,
                     force_share);
 
@@ -4298,8 +4389,13 @@ static int img_dd(int argc, char **argv)
         goto out;
     }
 
-    blk2 = img_open(image_opts, out.filename, out_fmt, BDRV_O_RDWR,
-                    false, false, false);
+    /* TODO, we can't honour --image-opts for the target,
+     * since it needs to be given in a format compatible
+     * with the bdrv_create() call above which does not
+     * support image-opts style.
+     */
+    blk2 = img_open_file(out.filename, NULL, out_fmt, BDRV_O_RDWR,
+                         false, false, false);
 
     if (!blk2) {
         ret = -1;
@@ -4363,6 +4459,239 @@ out:
     return 0;
 }
 
+static void dump_json_block_measure_info(BlockMeasureInfo *info)
+{
+    QString *str;
+    QObject *obj;
+    Visitor *v = qobject_output_visitor_new(&obj);
+
+    visit_type_BlockMeasureInfo(v, NULL, &info, &error_abort);
+    visit_complete(v, &obj);
+    str = qobject_to_json_pretty(obj);
+    assert(str != NULL);
+    printf("%s\n", qstring_get_str(str));
+    qobject_decref(obj);
+    visit_free(v);
+    QDECREF(str);
+}
+
+static int img_measure(int argc, char **argv)
+{
+    static const struct option long_options[] = {
+        {"help", no_argument, 0, 'h'},
+        {"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+        {"object", required_argument, 0, OPTION_OBJECT},
+        {"output", required_argument, 0, OPTION_OUTPUT},
+        {"size", required_argument, 0, OPTION_SIZE},
+        {"force-share", no_argument, 0, 'U'},
+        {0, 0, 0, 0}
+    };
+    OutputFormat output_format = OFORMAT_HUMAN;
+    BlockBackend *in_blk = NULL;
+    BlockDriver *drv;
+    const char *filename = NULL;
+    const char *fmt = NULL;
+    const char *out_fmt = "raw";
+    char *options = NULL;
+    char *snapshot_name = NULL;
+    bool force_share = false;
+    QemuOpts *opts = NULL;
+    QemuOpts *object_opts = NULL;
+    QemuOpts *sn_opts = NULL;
+    QemuOptsList *create_opts = NULL;
+    bool image_opts = false;
+    uint64_t img_size = UINT64_MAX;
+    BlockMeasureInfo *info = NULL;
+    Error *local_err = NULL;
+    int ret = 1;
+    int c;
+
+    while ((c = getopt_long(argc, argv, "hf:O:o:l:U",
+                            long_options, NULL)) != -1) {
+        switch (c) {
+        case '?':
+        case 'h':
+            help();
+            break;
+        case 'f':
+            fmt = optarg;
+            break;
+        case 'O':
+            out_fmt = optarg;
+            break;
+        case 'o':
+            if (!is_valid_option_list(optarg)) {
+                error_report("Invalid option list: %s", optarg);
+                goto out;
+            }
+            if (!options) {
+                options = g_strdup(optarg);
+            } else {
+                char *old_options = options;
+                options = g_strdup_printf("%s,%s", options, optarg);
+                g_free(old_options);
+            }
+            break;
+        case 'l':
+            if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
+                sn_opts = qemu_opts_parse_noisily(&internal_snapshot_opts,
+                                                  optarg, false);
+                if (!sn_opts) {
+                    error_report("Failed in parsing snapshot param '%s'",
+                                 optarg);
+                    goto out;
+                }
+            } else {
+                snapshot_name = optarg;
+            }
+            break;
+        case 'U':
+            force_share = true;
+            break;
+        case OPTION_OBJECT:
+            object_opts = qemu_opts_parse_noisily(&qemu_object_opts,
+                                                  optarg, true);
+            if (!object_opts) {
+                goto out;
+            }
+            break;
+        case OPTION_IMAGE_OPTS:
+            image_opts = true;
+            break;
+        case OPTION_OUTPUT:
+            if (!strcmp(optarg, "json")) {
+                output_format = OFORMAT_JSON;
+            } else if (!strcmp(optarg, "human")) {
+                output_format = OFORMAT_HUMAN;
+            } else {
+                error_report("--output must be used with human or json "
+                             "as argument.");
+                goto out;
+            }
+            break;
+        case OPTION_SIZE:
+        {
+            int64_t sval;
+
+            sval = cvtnum(optarg);
+            if (sval < 0) {
+                if (sval == -ERANGE) {
+                    error_report("Image size must be less than 8 EiB!");
+                } else {
+                    error_report("Invalid image size specified! You may use "
+                                 "k, M, G, T, P or E suffixes for ");
+                    error_report("kilobytes, megabytes, gigabytes, terabytes, "
+                                 "petabytes and exabytes.");
+                }
+                goto out;
+            }
+            img_size = (uint64_t)sval;
+        }
+        break;
+        }
+    }
+
+    if (qemu_opts_foreach(&qemu_object_opts,
+                          user_creatable_add_opts_foreach,
+                          NULL, NULL)) {
+        goto out;
+    }
+
+    if (argc - optind > 1) {
+        error_report("At most one filename argument is allowed.");
+        goto out;
+    } else if (argc - optind == 1) {
+        filename = argv[optind];
+    }
+
+    if (!filename &&
+        (object_opts || image_opts || fmt || snapshot_name || sn_opts)) {
+        error_report("--object, --image-opts, -f, and -l "
+                     "require a filename argument.");
+        goto out;
+    }
+    if (filename && img_size != UINT64_MAX) {
+        error_report("--size N cannot be used together with a filename.");
+        goto out;
+    }
+    if (!filename && img_size == UINT64_MAX) {
+        error_report("Either --size N or one filename must be specified.");
+        goto out;
+    }
+
+    if (filename) {
+        in_blk = img_open(image_opts, filename, fmt, 0,
+                          false, false, force_share);
+        if (!in_blk) {
+            goto out;
+        }
+
+        if (sn_opts) {
+            bdrv_snapshot_load_tmp(blk_bs(in_blk),
+                    qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID),
+                    qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME),
+                    &local_err);
+        } else if (snapshot_name != NULL) {
+            bdrv_snapshot_load_tmp_by_id_or_name(blk_bs(in_blk),
+                    snapshot_name, &local_err);
+        }
+        if (local_err) {
+            error_reportf_err(local_err, "Failed to load snapshot: ");
+            goto out;
+        }
+    }
+
+    drv = bdrv_find_format(out_fmt);
+    if (!drv) {
+        error_report("Unknown file format '%s'", out_fmt);
+        goto out;
+    }
+    if (!drv->create_opts) {
+        error_report("Format driver '%s' does not support image creation",
+                     drv->format_name);
+        goto out;
+    }
+
+    create_opts = qemu_opts_append(create_opts, drv->create_opts);
+    create_opts = qemu_opts_append(create_opts, bdrv_file.create_opts);
+    opts = qemu_opts_create(create_opts, NULL, 0, &error_abort);
+    if (options) {
+        qemu_opts_do_parse(opts, options, NULL, &local_err);
+        if (local_err) {
+            error_report_err(local_err);
+            error_report("Invalid options for file format '%s'", out_fmt);
+            goto out;
+        }
+    }
+    if (img_size != UINT64_MAX) {
+        qemu_opt_set_number(opts, BLOCK_OPT_SIZE, img_size, &error_abort);
+    }
+
+    info = bdrv_measure(drv, opts, in_blk ? blk_bs(in_blk) : NULL, &local_err);
+    if (local_err) {
+        error_report_err(local_err);
+        goto out;
+    }
+
+    if (output_format == OFORMAT_HUMAN) {
+        printf("required size: %" PRIu64 "\n", info->required);
+        printf("fully allocated size: %" PRIu64 "\n", info->fully_allocated);
+    } else {
+        dump_json_block_measure_info(info);
+    }
+
+    ret = 0;
+
+out:
+    qapi_free_BlockMeasureInfo(info);
+    qemu_opts_del(object_opts);
+    qemu_opts_del(opts);
+    qemu_opts_del(sn_opts);
+    qemu_opts_free(create_opts);
+    g_free(options);
+    blk_unref(in_blk);
+    return ret;
+}
 
 static const img_cmd_t img_cmds[] = {
 #define DEF(option, callback, arg_string)        \